Title - Smart Coatings: Degradation Of Priority Pollutants On TiO2 Based Photocatalytic Materials In Indoor And Outdoor Environments-Principles And Mechanisms

Speaker Abstract

The Heterogeneous Photo-catalysis Using Semiconductors E.g.TiO2 Is A Promising Technology For The Degradation Of Environmental Pollutants. Preliminary Evidence Indicates That Materials And Paints Enriched With TiO2 Degrade, Upon Activation With UV-light, NOx Gases And Volatile Organic Compounds (VOCs) E.g. Benzene, Toluene At Concentrations Typical For The Urban Environment. The Photocatalytic TiO2-materials And Paints Developed Are Primarily For Use Outdoors, On Facades In High Traffic Roads. Due To Its Band Gap Of 3.2 EV, TiO2 Is Effective Only In The UV-region (ca. 5%) Of The Solar Spectrum And With Wavelengths <380 Nm. Hence, Efforts Made To Increase The Area Of Activity Of TiO2 Using Visible Light, Which Will Expand Its Application To Improve The Quality Of Indoor Environments. The Photocatalytic Activity Of TiO2 Depends On The Lifetime Of Charge Carriers - Positive Holes And Electrons - Produced On Its Surface. Recombination Of Positive Holes And Electrons Occurs In An Extremely Short Time With Most Charge Carriers Recombining At The Surface Of The Semiconductor Before Undergoing Redox Reactions. In This Case No Reaction Takes Place. One Way To Reduce Or Inhibit Recombination Is To Blend/dope TiO2 With Transition Metals, Which Create Traps For Electrons And /or Positive Holes And Block The Charge Carriers By Reducing The Recombination Rate. Doping (change/modification Of The Crystalline Structure Of TiO2) Causes A Bathochromic (red) Shift, Which Results In A Reduction In The Energy Gap Leading To Increased Absorption In The Visible Light Region. Many Transition Metals Such As V, Cr, Fe, Mn, Ni, Co, Cu, Zn Have Been Explored To Reduce The Energy Gap And Facilitate The Transfer Of Electrons To The Conduction Band And Thus Extend The Spectral Range Of Modified TiO2 To The Area Of Visible Light. In Our Experiments, 0.1% (w/w) And 1% (w/w) Mn-TiO2 Admixtures Were Prepared And The Ability Of The Modified Photo-catalysts To Degrade NO By Both Solar And Indoor Illumination Was Evaluated. Principles And Mechanisms Of The Photocatalytic Reaction At The Air/catalyst Interface And The Possible Formation Of Undesired By-products Through The Photocatalytic Reaction Of TiO2 With Organic Paint Matrices Are Discussed.

Speaker Biography

Dimitrios Kotzias (Ph.D In Chemistry, University Of Bonn/Germany) Was Acting Director Of The Institute For Health And Consumer Protection (IHCP) And Head (retired) Of The Chemical Assessment And Testing Unit At The European Commission's Joint Research Centre (JRC), Ispra/Italy. His Research Activities Focused On Trace Analysis Of Organic Compounds In Complex Matrices, Photochemical And Photocatalytic Reactions, Photochemical Oxidants, Indoor Air Quality And Exposure Assessment To Chemicals And Chemical Mixtures. Founding Member And For Many Years President Of The Mediterranean Scientific Association Of Environmental Protection (MESAEP).

Title - Dental Zirconia Waste For A Sustainable Manufacturing Of Oil-water Separation Membranes

Speaker Abstract

Dental Zirconia Powder Is A Common Non-hazardous Waste From Orthodontic Laboratories And More Than 2000 Tons Of Waste Zirconia Are Treated And Disposed Yearly. Waste Recycling To Produce New Materials Is One Of The Possible Strategies Toward Sustainable Technological Development. In This Presentation, The Sustainable Manufacturing Of New Oil-water Separation Membranes Prepared From Dental Zirconia Waste Is Discussed. Zirconia-based Compounds Have Outstanding Hardness, Whiteness, Chemical Stability, And No Toxicity. Our Approach Combines The Advantageous Properties Of Zirconia With Reduced Production Costs, If Compared To The Commercial Zirconia Membranes. At The Same Time, Waste Is Reduced And There Is No Need To Consume Materials, Time, And Energy For Producing The Nanoparticles Usually Required For Membrane Fabrication. Membranes Were Prepared By Spin Coating Water Dispersions Of Dental Zirconia Waste On Commercial Silicon Carbide Supports. Both The Zirconia Powders And The Obtained Membranes Were Characterized For Their Chemical Physical Properties And Correlated With The Selectivity In Olive Oil Retention And The Water Permeability.

Speaker Biography

Francesca Deganello Is Research Chemist At CNR-ISMN (Istituto Per Lo Studio Dei Materiali Nanostrutturati) In Palermo (Italy) Since 2001. She Obtained Degree In Chemistry And Ph.D In Chemical Sciences At Università Degli Studi Di Palermo, Italy. She Visited National And International Laboratories Like Trieste University (Italy), Tokyo University (Japan) And INRS-EMT (Canada). Her Current Research Interests Concern The Sustainable Synthesis Of Nanomaterials For Energy And Environmental Applications. She Is Responsible For The ISMN Unit Of European Projects Concerning The Wastewater Pollutants Abatement. She Is Scientific Tutor/co-tutor Of Undergraduate, Ph.D And Post. Doc Students. She Also Deals With The Communication And Dissemination Of Chemistry To Schools And Public And Performs Reviewing And Editorial Activity For Materials-related Journals.

Title - Synthesis, Modeling And Applications Of III-V Nanowires And Nanowire Heterostructures: Opportunities And Challenges

Speaker Abstract

We Will Review The State-of-the Art Research In The Field Of Synthesis And Modeling Of III-V Semiconductor Nanowires (NWs) And Photonic Nano-heterostructures Based On Such NWs. Some Recent Advancements Will Be Discussed, Including Coherent Growth In Regular Arrays On Silicon Substrates And Some Growth Features Of The Vapor-liquid-solid Growth Which Enable Controllable Tuning Of The NW Morphology, Composition, Crystal Phase And Statistical Properties Of The Size Distributions Within The Ensembles Of NWs. Opportunities And Challenges For Optoelectronic Applications Of III-V NW Heterostructures Will Be Discussed, Including Single Photon Generation.

Speaker Biography

V. G. Dubrovskii Is A Professor And Head Of The Laboratory Of Physics Of Nanostructures At Faculty Of Physics, St. Petersburg State University. His Research Interests Are In Modeling Of Semiconductor Nanowires And Design Of Optoelectronic Nanomaterials. He Has Received A Number Of Awards And Honors Including Chevalier Of Ordre Des Palmes Académiques, France (2017), Doctor Honoris Causa Of Université Clermont Auvergne, France (2020), And Regular High-level Visiting Scientist In IGAT Base At Beijing University Of Posts And Telecommunications, China (2007-2018).

Artical Title: Co-processing of biomass-methane-CO2 for hydrogen production

Abstract

Transition from fossil fuels to renewable technologies is extremely challenging as renewable energy sources like solar, wind, and biomass are highly unreliable, subject to variation in geography and local climatic conditions. Transition from fossil hydrogen to renewable hydrogen is bridged by the unique ‘natural gas – biomass co-processing. At WVU, hydrogen rich syngas production through renewable hardwood biomass gasification was obtained through synergistic natural gas – biomass co-processing. About 5% methane co-processed with biomass at 850oC on Fe-Mo/CNF catalyst produces H2: CO ratio of 6 with a very low CO2 concentration of < 5% in the syngas. About 60 to 80% hydrogen was obtained in the product gas on the Fe-Mo/CNF, Ni-Mo/CNF, and Mo-Pd/CNF catalysts. Synergistic methane activated biomass gasification could be a promising technology for hydrogen rich syngas production as it requires very low concentrations of methane which could be obtained from flare gas. Flare gas is natural gas flared during commissioning of new wells or maintenance of existing wells in shale gas field. On-site utilization of flare gas with biomass could greatly curb CO2 emission while producing hydrogen rich syngas. CO2 utilization in the methane activated biomass gasification was studied by adding 1% CO2 to the gas feed. CO2 and CH4 activation at high temperature was performed on Fe, Ni, and Pd active sites while Mo active sites are responsible for deoxygenation of oxygen rich biomass. In-situ conversion of raw biomass co-processed with 5% methane produces H2-rich syngas on the carbon nanofiber supported catalyst. CNF support is also obtained from the biomass feedstock by impregnation with metals and pyrolysis at 700oC. This process is 95% renewable with net reduction in CO2 emissions by recycling of CO2. Detailed mechanistic investigation through molecular simulations helped ascertain the unique reaction pathway occurring on dual active sites on a transition metal doped β-Mo2C-CNF catalyst. Application of renewable technologies is on the rise especially in power generation but is still far from being a mainstream source of hydrogen and power.

Biography

Artical Title: Finite element investigation of thermal-kinetic-mechanical evolutions during laser powder deposition as an innovative technique for rail repair

Abstract

Utilization of laser powder deposition (LPD) as an innovative repair tool for damaged steel components is increasingly growing in recent years. This paper investigates repairing a standard US light rail using LPD. No study has focused on repairing standard US rails thus far. Besides, this is the first time that a three-dimensional finite element model is developed where element-birth-and-kill technique is employed to study thermal-kinetic-mechanical evolutions during the LPD rail repair process. Exploration of hardness versus microstructure yielded a reverse correlation between hardness level and austenite volume fraction. The maximum hardness was found near rail-deposition interface with the minimum austenite concentration, while the topmost deposition layer with the highest austenite concentration showed the minimum hardness. Longitudinal residual stresses at the rail-deposition interface were significantly more than that of transversal and normal. Comparing the residual stress against deposition material yield strength showed a slight exceedance (~5%) of transversal stress from the maximum limit, no exceedance for normal stress, but an extreme exceedance of 50%for longitudinal stress. This fact suggested a high risk of cracking along longitudinal direction at the rail-deposition interface, while there existed only a minor risk of transversal cracking and almost no chance of layer delamination. The simulated results were compared against experimental results obtained via optical and scanning electron microscopy, hardness test, and X-ray diffraction stress measurement, where a maximum deviation of 10% proved the model accuracy. The validated model in this study would be a great backbone for future studies on different process parameters to increase hardness and reduce stress in an LPD repaired rail.

Biography

Artical Title: Towards a generic physics-based machine learning model for geometry invariant thermal history prediction in additive manufacturing

Abstract

Additive manufacturing (AM) is an emerging manufacturing technology that constructs complex parts through layer-by-layer deposition. The prediction and control of thermal fields during production of AM parts are of crucial importance as the temperature distribution and gradient dictates the microstructures, properties, and performance. Finite element (FE) analyses are commonly conducted to simulate the thermal history of the AM process, but are known to be costly and time-consuming. This paper aims to address the challenge by presenting the essential components of a generic data-driven control framework. The proposed framework utilizes extremely randomized trees and is trained and tested on datasets generated through FE simulations. The datasets contain generic, engineered features constructed based on the physics of the underlying thermal process. The features are transferable between a wide ranges of cases and have achieved mean absolute percentage errors (MAPE) below 2.5% for predicting nodal temperature profiles. In addition, predictions of entire simulations with machine learning (ML) models trained on datasets from different cases have been conducted with MAPE below 5%. The results demonstrate the transferability of thermal histories between several geometries and significantly reduce the need for expensive FE simulations. We believe that these findings are an important step towards real-time optimization in AM.

Biography

Artical Title: Microstructural changes in additively manufactured Co-Cr-Mo alloy during cyclic loading

Abstract

Cobalt-Chromium-Molybdenum (CoCrMo) alloys are used in applications that require high strength and wear resistance. Examples in biomedical area include artificial hip and knee joints implants that are subjected to repetitive loads during the service. The cyclic loading implies high fatigue strength as fundamental mechanical property, besides those already pointed out. In this regard, it is crucial to understand the mechanism associated with the crack propagation. Therefore, in this work, microstructural changes associated with crack propagation during cyclic loading of a CoCrMo alloy were investigated. Tensile test specimens were manufactured using laser powder bed fusion (LPBF) additive manufacturing technique and examined in the as-build condition. The sample was subjected to cycling loading with constant tension load applied (above the yield strength of the material) and subsequent tension release, Figure 1a. Figure 1a shows an initial linear increase in strain hardening based on the deformation-induced martensitic transformation commonly present in materials with low or negative stacking fault energy. Microstructural changes were followed using electron backscatter diffraction (EBSD) technique. Figure 1b shows a typical as-build microstructure with a single-phase face-centered cubic (γ) structure, consistent to reported previously. After 5100 cycles, it was possible to trace deformation-induced phase transformation from γ to hexagonal close-packed (ε) structure, Figure 1c. Our investigation also revealed that cracks nucleated at the ε-phase formed at grain boundaries. In addition, it was observed that the crack tip was deflected when encountered a grain boundary unfavorably oriented to the crack propagation. Then the crack tip propagated further at the ε-phase inside the grain. Therefore, γ → ε deformation-induced martensitic phase transformation serves as a preferential path to the crack propagation.

Biography

Artical Title: Effect of fluoride conversion pretreatment time and the microstructure on the corrosion performance of TEOS-GPTMS sol-gel coatings deposited on the WE54 magnesium alloy

Abstract

Magnesium and its alloys have been considered as revolutionary materials for automotive and aerospace applications owing to their unique specific mechanical properties. In particular, the WE54 alloy (Mg-Y-RE-Zr) is conventionally employed in the fabrication of high-performance vehicles due to the presence of Y and RE that confers excellent mechanical response at relatively high temperatures. Unfortunately, the major drawback in the use of Mg alloys is their low corrosion resistance in aqueous environments, which leads to early loss of their mechanical integrity. At present, a promising approach to enhance the corrosion behaviour of these alloys is the synthesis of TEOS (tetraethylorthosilicate) / GPTMS (glycidoxypropyltriethoxysilane) hybrid sol-gel coatings as they offer good corrosion resistance, strong adhesion, flexibility and low cracking tendency. Nevertheless, their protective features could be considerably affected by the high reactivity of the Mg alloys with the acidic sol during the deposition stage, causing the formation of corrosion products at the metal/coating interface. In order to overcome this limitation, it has been suggested the development of a fluoride-based conversion pretreatment that promotes the formation of a magnesium hydroxyfluoride layer with protective characteristics. In this regard, the aim of the present investigation was to evaluate the employment of a fluoride-based pretreatment of the WE54 magnesium alloy on the protection-degradation mechanism of TEOS /GPTMS hybrid sol-gel coatings when in contact with saline environment, giving special attention to the influence of the pretreatment time. The experimental results evidenced that long pretreatment times favoured the formation of a magnesium hydroxyfluoride layer with a higher F/O ratio, which improved the corrosion performance of the sol-gel coatings and the WE54 alloy. However, the presence of undissolved intermetallic particles and Y-rich precipitates on the surface led to structural defects that allowed the corrosive attack to evolute along the immersion time in saline solution.

Biography

Artical Title: La-doped ZnTiO3 or TiO2 and supported on ecuadorian diatomaceous earth as a highly efficient photocatalyst driven by solar light

Abstract

Nowadays, there is a great interest in the use of TiO2 for photocatalytic remediation of wastewater. Doping, heterojunction and immobilization on porous materials are effective methods to improve the photocatalytic efficiency of this semiconductor. In this study, ZnTiO3/TiO2 (ZTO) and ZnTiO3/TiO2/La (ZTO/La) nanocomposites were successfully prepared by the sol-gel method and immobilizing on diatomaceous earth (DE). The composition and texture of the prepared composites were characterized by X-Ray diffractometry (XRD), X-Ray Fluorescence (XRF), Diffuse Reflectance Spectroscopy (DRS), Scanning Electron Microscopy (SEM-EDX) and specific surface area (SSA). The adsorption capacity and photocatalytic activity of composites were determined via degradation of methylene blue (MB) in batch reactors. The materials evaluated were prepared in the shape of 0.2 cm (diameter) and 1.0 cm (length) cylindrical extrudates. The results indicated that the ZTO/La-DE composite exhibits a higher efficiency of removal of MB than ZTO-DE and DE under solar irradiation. The Langmuir isotherm model and the pseudo-second-order model were better suited to the adsorption process. The higher degradation percentage of MB obtained was 96% after 150 min of irradiation. The results reflect that synthesized composite could be used potentially for the removal of cationic dye from wastewater.

Biography

Artical Title: Design and operation of low energy consumption passive human comfort solutions

Abstract

The rapid growth during the last decade has been accompanied by active construction, which in some instances neglected the impact on the environment and human activities. Policies to promote the rational use of electric energy and to preserve natural non-renewable resources are of paramount importance. Low energy design of urban environment and buildings in densely populated areas requires consideration of wide range of factors, including urban setting, transport planning, energy system design and architectural and engineering details. The focus of the world’s attention on environmental issues in recent years has stimulated response in many countries, which have led to a closer examination of energy conservation strategies for conventional fossil fuels. One way of reducing building energy consumption is to design buildings, which are more economical in their use of energy for heating, lighting, cooling, ventilation and hot water supply. However, exploitation of renewable energy in buildings and agricultural greenhouses can, also, significantly contribute towards reducing dependency on fossil fuels. This will also contribute to the amelioration of environmental conditions by replacing conventional fuels with renewable energies that produce no air pollution or greenhouse gases. This study describes various designs of low energy buildings. It also, outlines the effect of dense urban building nature on energy consumption, and its contribution to climate change. Measures, which would help to save energy in buildings, are also presented.

Biography

Artical Title: Multicomponent high-entropy cantor alloys

Abstract

All human advances have depended on making new materials, and all materials are alloys, i.e. mixtures of several different starting materials or components. So the history of the human race has been the continued invention of new materials by discovering new alloys. Recently a new way of doing this, by manufacturing multicomponent high-entropy alloys, has shown that the total number of possible materials is enormous, even more than the number of atoms in the galaxy, so we have lots of wonderful new materials yet to find. And multicomponent phase space contains a surprisingly large number of extended solid solutions. The first group of these which was discovered are called Cantor alloys, an enormous composition range with a single-phase Fcc structure, based loosely on the original equiatomic five-component Cantor alloy CrMnFeCoNi. This talk will discuss the previous history of alloying, the discovery of multicomponent alloys, the structure of multicomponent phase space, the fundamental thermodynamics of multicomponent solid solutions such as the Cantor alloys, the complexity of local atomic and nanoscale configurations in such materials, the effect of this on properties such as atomic diffusion, dislocation slip, and the resulting outstanding mechanical properties and potential applications.

Biography

Artical Title: Atomic ordering at liquid-metal or oxide interfaces from Ab initio modelling

Abstract

Oxide particles, magnesia, spinel and alumina are formed in the liquid light metals inevitably during liquid metal dealing and casting. They play an important role in determination of the properties of the cast parts, and may also act as potential nucleation sites to achieve effective grain refinement. Thus, understanding of the atomic ordering at liquid-metal/oxide (L-M/oxide) interfaces is a prerequisite for controlling the heterogeneous nucleation during casting. Here, we briefly overview recent studies devoting to improve the understanding of atomic ordering at the liquid-metal/oxide interfaces from ab initio molecular dynamics (AIMD) simulations. We identified a formed metal layer terminating the oxide substrates, MgO {1 1 1}, α-Al2O3 {0 0 0 1}, MgAl2O4 {1 1 1} and γ-Al2O3 {1 1 1} in the liquid metals. The liquid metal atoms near the interfaces exhibit atomic ordering, as shown in Fig.1 for L-Al/spinel {1 1 1} as an example. The terminating metal atoms exhibit unusual chemistry: being positively charged and topologically rough, which impact strongly the atomic ordering at the interfaces. The obtained information is helpful not only for obtaining insight into the potency of the oxide particles, further for controlling of the solidification, but also for better understanding of ceramic coating of metals and of metal/oxide composite materials.

Biography

Artical Title: Investigation of the characteristics of expanded polystyrene (EPS) foam beads mixture as a lightweight construction material

Abstract

This research investigates the natural and the mechanical characteristics of the lightweight expanded polystyrene (EPS) foam beads mixture as a lightweight construction material. to solve problems of construct embankments and abutments of highways on weak soil by reducing the weight of soil. In this research, the mixture was prepared using foam beads, sand, cement and water. The foam beads and sand were mixed with ratio 1:1 by volume and mixed with cement content by percentage 7%, 8%, 9% and 10% of sand weight using the optimum water content. Experimental tests were carried out to evaluate natural properties and mechanical properties such as: unit weight, shear strength parameter, compressibility, and crushing strength. The results found that, the high cement ratio of 10% formed lightweight mass with acceptable crushing strength, CBR and compressibility characteristics. The results show that, the cement contents and curing time effect on the properties of the mixture.

Biography

Artical Title: Energy storage and the compressibility of atoms

Abstract

The development of reversible energy storage in ‘rocking chair’ batteries using Lithium ions usually requires research on special materials for the electrodes. The requirement is essentially that they can act as suitable hosts for the storage of lithium ions. Lithium ions have the electronic configuration of helium and can therefore be categorised as the hardest (i.e. least compressible) of the singly charged ions. Reversible storage therefore requires, in addition to freedom of movement of the ions through the lattice, that the host material should possess the flexibility required to store the ion and subsequently eject it without any recrystalisation, because the latter would imply a change of phase of the host material and hence a loss of energy and reversibility. The storage-recovery cycle often makes use of polaronic distortion of the lattice, which implies the use of ‘soft’ or highly compressible constituent atoms. It will be shown that these ‘soft’ atoms belong to a specific class for which the outer electrons are subject to a double-well quantum-mechanical potential. Such atoms belong to a limited class in the Periodic Table. Thus, specific atoms are singled out as the most favourable. A table involving such atoms will be presented.

Biography

Artical Title: Advanced laser technology for quantum communications

Abstract

In this new decade our societies will face rapid changes and will need to adapt to a wide range of new technologies emerging from the quantum world. Among them, quantum communications is set to occupy a central place in our future ways of exchanging and processing of information: by exploiting the laws of quantum mechanics, it allows transferring and manipulating information beyond the capabilities of our conventional technologies. Owing to the threat of quantum computers against conventional public key cryptography algorithms methods, quantum key distribution (QKD) arose as means to establish symmetric encryption keys between distant parties, with information theoretic security. In the recent years, QKD has demonstrated a high level of maturity, which motivated governments and industry partners to work towards the development of large-scale quantum communication infrastructures. This perspective poses an immediate practicality challenge: how to encode quantum information in a versatile way while preserving the constraints of low-cost production, high power efficiency, small size and high scalability required for a viable integration in our conventional communication infrastructure? In this talk, we present recent advances in laser modulation technologies that have enabled the development of efficient and versatile light sources for quantum communications. Based-on on appropriate combinations of different features of well-known laser physics, these sources have been used to demonstrate several QKD protocols with state-of-the-art performance. After introducing the concepts of quantum cryptography and advanced laser modulation techniques, we review and interpret the applications and experimental results enabled by this new approach in the light of a complete theoretical framework.

Biography

Artical Title: 3D-printed hierarchical pillar array electrodes for high performance semi-artificial photosynthesis

Abstract

The re-wiring of photosynthetic bio-machineries to electrodes is a forward-looking semi-artificial route for sustainable bio-electricity and fuel generation. Currently, it is unclear how the bio-material interface can be designed to meet the complex requirements for high bio-photoelectrochemical performance. Here, we developed an aerosol jet printing method for generating hierarchical electrode structures using indium tin oxide nanoparticles. We printed libraries of micropillar array electrodes varying in height and sub-micron surface features and studied the energy/electron transfer processes across the bio-electrode interfaces. When wired to the cyanobacterium Synechocysis sp. PCC 6803, micropillar array electrodes with micro-branches exhibited favourable biocatalyst loading, light utilisation and electron flux output, ultimately almost doubling the photocurrent of state-of-the-art porous structures of the same height. When the micropillars’ heights were increased from 50 to 600 µm, milestone mediated photocurrent densities of 245 µA cm–2 (the closest thus far to theoretical predictions) and external quantum efficiencies of up to 29% could be reached. This study demonstrates how bioenergy from photosynthesis could be more efficiently harnessed in the future and provide new tools for 3D electrode design.

Biography

Artical Title: Interface engineering of solid garnet batteries

Abstract

The solid-solid interfacial contact is a critical issue during the studies of solid-state batteries (SSBs), which greatly affects the electrochemical performance of SSBs, such as the coulombic efficiency, and cycle life. For flexible polymer/garnet electrolytes (PGEs), the interfacial issue mainly comes from the interactions between the inorganic fillers and the polymer matrix. The slow Li + transport through the polymer/garnet interface can lead to the low ionic conductivity of PGEs. While for garnet ceramic electrolytes (GCEs), the ceramic bulk with a relative density over 99% shows no obvious grain boundary, leading to the ionic conductivity over 10-3Scm-1 at room temperature. Under this circumstance, the interfacial issue could be attributed to the poor interfacial contact between the GCEs and Li metal anodes. It can induce the large interfacial resistance as well as the lithium dendrite growth. In this presentation, I’ll focus on the aforementioned interfacial issues, various targeted strategies will be introduced to construct the excellent interfacial structure, thus significantly improving the performance of SSBs.

Biography

Artical Title: Studying the residual macrostress and texture development upon low temperature nitriding of Co-Cr alloys

Abstract

Low temperature gaseous nitriding of Co-Cr alloys at 400°C with the initial hexagonal close-packed (hcp) crystal structure results in the development of supersaturated hcp phase with the incoming nitrogen atoms. The residual macrostress develops on the surface as a result of volume misfit between the nitrided case and the untreated core. This macrostress affects the nitriding behavior of differently-orientated hcp variants at the surface, in a way that their further transformation to face-centered cubic (fcc) phase is anisotropic. The intent of current research is to investigate the magnitude of this residual macrostress as well as the resulted texture on the surface of nitrided specimen. The stress measurements were carried out using stress analysis method by X-ray diffraction, so-call the Sin2ψ method, on a surface of specimen with the nitrided layer containing expanded hcp phase. The measured (101) lattice spacings against Sin2ψ depicts an oscillation, which can be ascribed to the crystallographic texture. In addition, re-orientation of surface adjacent grains with respect to their orientation in the core is realized using electron backscatter diffraction (EBSD). The lattice elongation perpendicular to the specimen ´s surface can be assumed similar to the deformation resulted from the uniaxial tension. In a case of a sever deformation, an obvious texture may be observed for the grains at the surface similar to the fibre texture that can be achieved after the uniaxial tension of hcp materials.

Biography

Artical Title: How does the glass beads impact the behavior of the failure pattern in bonded joints

Abstract

New materials and coatings have been introduced in car manufactures to reduce vehicle weight and improve corrosion resistance. In body shop, multimaterial design is joined using structural adhesives. The former epoxy crash adhesive gave adhesive failure on new steel coatings. This kind of failure is not accepted by carmakers. One way to obtain cohesive failure, is by adding glass beads in adhesive formulations. The aim of this work was to analyze how the addition of glass beads to the adhesive layer affects the failure mechanism. Single lap bonded specimens with mild steels were tested in quasi-static conditions and with different amount of glass microspheres. The results showed that the glass microspheres act as reinforcement particles which introduce stress concentration around the particles and their vicinities. This new phenomenon led the cracks to propagate in the middle of the adhesive layer rather than interfacial. This promote the cohesive failure. This novel effect solved the adhesion issue on difficult surfaces.

Biography

Artical Title: Floating photocatalysts to exploit sunlight in water remediation

Abstract

In the last decades, the attention to environmental issues and the race to develop eco-friendly processes, has further attracted the field of research towards an inexpensive, simple, and reliable technology. A concerning global issue is freshwater scarcity mainly caused by leaking landfills, industrial waste, and sewage. In this regard, heterogeneous photocatalysis could offer a feasible solution to this problem aiming at the development of photoactive devices suitable for water remediation. Although TiO2 is still the most used semiconductor due to its chemical and physical stability, good photoactivity and low cost, researchers are willing to replace it with new smart materials because of its suspected carcinogenic nature and limited activity under solar light. Among them, g-C3N4 has promising features as photocatalyst for water-remediation considering its visible-light response, simple synthetic pathway, and peculiar layered structure and cheap production cost. To overcome problems related to the use of slurry systems for water purification, new floating substrates were employed to immobilize the photocatalyst. Since their closeness to water-surface, these devices can be fully irradiated by light source, better oxygenated, and easily recovered and reused. Within this framework, synthetic polymers are commonly used as support, however their non-degradability has raised ecological concerns. Instead, an eco-friendly alternative can be the use of natural polymers, such as alginate, which derives from brown seaweeds and can be used for the immobilization of photocatalysts under safe and mild conditions. In the present study, different methods were applied in order to synthesize floating alginates as support for O-doped g-C3N4 catalysts, whose activity was improved under visible light by doping with oxygen. These materials were deeply studied for photodegradation of rhodamine B, sodium diclofenac and isoproturon in water under solar light irradiation. Furthermore, floating photocatalyst were subjected to recycle test, in order to verify their activity and stability after several experiments.

Biography

Artical Title: Metal-free-based photocatalytic materials: Advances and future perspectives for environmental and energy purposes

Abstract

The contemporary world is facing energy shortages and environmental problems, which hinder the evolution of human civilization giving rise to various types of crises. The huge energy consumption and environment pollution related to the traditional industrial processes, along with the increasing need of synthetic chemicals to satisfy the current society requirements, are urgent issues to be addressed for the development of the new foundations for a sustainable future. These critical challenges need solutions which require an important upgrade in energy sources and the conception of new generation processes and manufacturing technologies. Researchers, over the past few decades, have been studying several methods to understand how to overcome these problems. In this context, heterogeneous photocatalysis appears as one of the useful technologies to help these urgent efforts, and it can make a contribution to solve environmental problems and manage the conversion of solar energy into chemical energy in a sustainable way. Among the semiconductors to be used as photocatalysts, metal-free materials, such as graphene, nitrides, carbides, and conjugated organic polymers, have gained extensive research interest due to their earth abundance, cost-effectiveness, good electrical conductivity, and environmental friendliness. These semiconductors are active for photocatalytic H2 generation, CO2 reduction, and for environmental applications, not only for photocatalytic abatement of pollutants, both in gas-solid and liquid-solid regimes, but also for the valorization of substances obtained from biomass to obtain high added value chemicals. All of these applications of the photocatalytc technology are carried out in green conditions, by using water as solvent, at room temperature and atmospheric pressure by using natural solar irradiation as energy source. In the present work the recent progress from our laboratory research on metal-free photocatalysis will be systematically presented and also compared with the literature research. Opportunities and challenges on metal-free photocatalysts to enhance their activity under natural solar irradiation will be presented. Based on the aforementioned discussions, suitable future research directions and perspectives for the design and development of potential metal-free photocatalysts will be provided.

Biography

Artical Title: Ovarian masses-applicable IOTA ADNEX model versus morphological findings for accurate diagnosis and treatment

Abstract

A common problem in gynecological practice is the differential diagnosis of the ovarian masses. The clinician must apply the IOTA (International Ovarian Tumor Analysis) ADNEX (Assessment of Different Neoplasia in the Adnexa) model criteria to evaluate the risk of benign, borderline or malignant tumors. The aim of this study was to verify if the IOTA ADNEX model is a practical tool to be used before surgery and if there is a significant difference between IOTA ADNEX criteria and histological findings. A prospective single center study was performed between January 2017 and December 2019 in Obstetrics and Gynecology Hospital “Cuza-Voda”, Iasi, Romania. The study included 230 patients between 17 and 74 years old diagnosed with persistent adnexal masses. We applied the IOTA ADNEX model protocol predicting the risk of benign, borderline or malignant masses. The golden standard remains the histological diagnosis of the surgically removed mass. The patients that had been diagnosed using ultrasonography with persistent adnexal masses between 30 and 291 mm were operated on in our clinic. In our study the majority of patients had benign ovarian tumor mass, these being 223 (96.96%) patients, from whom, according to IOTA ADNEX protocol, the correspondence was: 91.8–99.7% at risk of benign tumors, 0.3–4.5% at risk of borderline tumors and 0.3–8.2% at risk of malignant masses. Unexpected findings were obtained from the malignant group that included five patients (2.17%) with the following correspondence: 96.1–99% at risk of benign tumors, 0.6–2.4% at risk of borderline tumors and 1–3.9% at risk of malignant masses. After applying the IOTA ADNEX model criteria, the patients with a suspicion of malignant disease were correctly guided towards surgical treatment in an oncological center. In our hospital, surgical treatment was only proposed to those patients with high suspicion of benign masses.

Biography

Artical Title: Several possible phase states in oxide ferroelectrics

Abstract

The analysis of phase diagrams, structure and crystal lattices dynamics of oxide ferroelectrics of lithium niobate and tantalate at various concentrations of topological defects was carried out. The structure and dynamics of the lattice in the region optical vibrations were studied by the methods of X-ray structural analysis, quasi-elastic and Raman light scattering spectroscopy. Sound absorption of longitudinal and shear waves and Q-factor of samples were obtained by the radio engineering method and by the Bragg light scattering on sound method. Three types of lithium niobate samples were prepared for the studies - those grown from a stoichiometric melt, grown from a congruent melt and grown from a congruent melt with different rates of pulling out the seed from the melt in order to create different concentrations of dislocations. We calculated the intensity of Raman light scattering in the frequency range 5 - 70 cm-1 at the model interaction of 2A1 (TO) symmetry optical vibration with acoustic vibrations relaxing on dislocations. The self-energy part of acoustic phonons was calculated from the Langevin equation. Good agreement of the calculated spectrum with the experimental one was obtained. The high degree of correlation between the parameters makes it possible to dispense with only one parameter in the used model - the concentration of topological defects in the samples. It is shown that there is a critical value of the concentration of topological macrodefects, at which a correlation occurs between dislocations.

Biography

Artical Title: Topological insulators: Myths and reality

Abstract

Topological insulators (TI) are a new kind of solids. Simply speaking they are bulk insulators with metallic surfaces. All semiconductors with the inverted band structure are the topological insulators. At the moment there are three myths about TI: Myth 1: the beauty of ARPES, Myth 2: topological insulators are the material of the future electronics, Myth 3: Topological protection against back scattering, and Myth 4: Chiral interconnection. The subject of this talk is the critical analyses of these mythes.

Biography

Artical Title: Antiphase boundary defects in Strontium-doped Lanthanum Scandate

Abstract

LaScO3-based oxides are promising oxide materials for solid oxide electrochemical devices, such as protonic ceramic fuel cells, electrolysis cells, and gas sensors. The substitution of La3+ lanthanum with strontium Sr2+ should lead to a decrease in the oxygen content in the oxide lattice in order to satisfy the electroneutrality condition. The 45Sc NMR method was used to study the local structure of La1–xSrxScO3–δ oxides (x = 0, 0.04, 0.09). Only one line was found on the 45Sc NMR spectra, which corresponded to the 6-coordinate scandium in strontium-doped lanthanum scandates, and the contribution of the quadrupole broadened part of the spectrum decreased with an increase in the level of doping with strontium, indicating an increase in the local symmetry of the Sc3+ ion. EBSD and TEM study shows the existence of a structural inhomogeneity in a polycrystalline sample of strontium-doped lanthanum scandate was found in comparison with the undoped oxide. Defects, represented as straight or arbitrarily curved lines that did not extend beyond the grain boundaries, were identified as π-type antiphase boundaries. The atomic structure of possible antiphase boundaries in lanthanum-strontium scandate perovskite, a promising proton conductor, was modelled by means of DFT method. Two structural types of interfaces were modelled: edge- and face-shared. Energetic stability of all interfaces was calculated along with the oxygen vacancy formation and migration energies. Mechanisms of oxygen migration in both types of interfaces were modelled. It was shown that both types of interfaces are structurally stable and permit oxygen ionic migration. Oxygen vacancy formation in face-shared interface is by 0.2 eV lower than that in the bulk. Oxygen migration, however, most likely, will be blocked by some high-energy barriers over the O−O bonds with shared faces.

Biography

Artical Title: Biodegradation and incineration as the final stages of the life cycle of polymer packaging in a circular economy

Abstract

Changing the profile of world trade in the context of the transition to a circular and low-carbon economy is inextricably linked to global flows of "polymer waste," which lead to "plastic pollution" of the planet and are subject to international regulation (EU Framework Directive 2008/98/EC). Polymer packaging is one of the largest use areas of polymer composite materials. We have found that the biodegradability to polymer composite materials based on a number of synthetic polymers, practically not decomposable in pure form, gives arabinogalactan (AG), one of the most important components of Siberian and Daurian larch - these types of larch contain up to 30%AG. We have established that AG is contained in larch in the form of an aquacomplex - "arabinogalactan-water". Such a complex has a freezing point below -60 °C and can be considered as a natural low-temperature eutectic that provides frost resistance to these larch species and the possibility of larch growing in permafrost. The AG-water complex for larch is the liquid phase that fills its capillary-porous structure and allows larch to survive in conditions of Siberian frosts and permafrost, and provides fatigue strength to its branches and roots. At the same time, larch roots can be considered as a carbon sequestration path, and the alternating wind load for a growing tree ensures the development of its root structure and increases the amount of carbon sequestered in the ground. There are offered industrial versions of arabinogalactans extraction from larch and versions of usage of sawdust with increased content of arabinogalactans as components of composite materials of packaging purpose. An advanced innovative technology has been developed for processing into fuel briquettes both sawdust and their mixtures with waste of synthetic polymers, including those with used plastic packaging.

Biography

Artical Title: Application of luminophore-containing compositions for modifying the spectral characteristics of diamonds in X-ray luminescent separation schemes

Abstract

Significant losses of diamonds during the enrichment of diamond-containing kimberlites according to the schemes of X-ray-luminescent separation (XLS) are due to the fact that some of the crystals have spectral-kinetic characteristics, the values of which go beyond the ranges of settings of X-ray-luminescent separators. The idea is substantiated and a technology is proposed to reduce the losses of weakly and anomalously luminescent diamonds in the XLS process of diamond-containing material using luminophore-containing compositions that provide an approximation of the anomalous spectral characteristics of non-recoverable diamonds to the standard parameters of natural crystals. With the chosen approach, a simultaneous increase in the convolution and the attenuation time constant of the X-ray luminescence signal is achieved. The effectiveness of the use of the luminophore FL-530, characterized by the presence of a pronounced slow component of the X-ray luminescence signal, and the anthracene luminophore with a large amplitude of the fast component, for modifying the spectral characteristics of diamonds is confirmed. The use of diesel fuel as an organic phase of a luminophore-containing emulsion that provides effective fixation of a luminophore-containing composition on diamonds is justified. The expediency of adding reagents to the organic and aqueous phases of the emulsion has been experimentally confirmed, which provide an increase in the adhesion and retention ability of the organic phase with respect to diamonds and luminophores or reduce the fixation of on kimberlite minerals. A mode of increasing the oleophilicity of the luminophore FL-530 by treatment with hydrophobizing reagents has been developed, which provides an increase in the retention capacity of the organic phase in relation to the luminophore and the efficiency of its fixation on the surface of diamonds.

Biography

Artical Title: Effect of phase transformations of a metal component on the magnetic and transport properties of nanocomposites Cox (MgF2)100- x and (CoFeZr)x (MgF2)100-x

Abstract

The aim of this work was to establish the effect of structural-phase transformations on the magnetic and transport properties of Cox(MgF2)100-x and (CoFeZr)x(MgF2)100-x nanocomposites depending on the metal or alloy content in the dielectric matrix MgF2 on the basis of complex studies by various methods: XRD, XPS, IR-spectroscopy, magneto-optical spectroscopy and electro-resistivity methods. The percolation thresholds in the system Cox (MgF2)100-x at х = 37 and in the system with the alloy (CoFeZr)x (MgF2)100-x at х = 30 determined from the concentration dependences of the electrical resistance of nanocomposites, coincide with the formation of metal nanocrystals in the dielectric matrix MgF2. The average size of metal nanocrystals in both systems varies within 10–20 nm. In magneto-optical studies on the concentration dependences of transversal Kerr effect (TKE) in the visible and near-IR regions of the spectrum in nanocomposites Cox(MgF2)100-x one maximum is observed at the percolation threshold at х = 37 which coincides with the formation of α-Co nanocrystals. When the content of cobalt x<42 Cox (MgF2)100-x nanocomposites exhibit a soft magnetic character, and at a higher metal content (x> 42), a hard magnetic character with a coercive force of up to 95 Oe. In nanocomposites (CoFeZr)x (MgF2)100-x two maxima appear on the concentration dependences of transversal Kerr effect in the visible and near-IR regions of the spectrum, one of which corresponds to the formation of hexagonal nanocrystals of the CoFeZr alloy at x = 30 and the second maximum at x = 45 corresponds to the phase transition of nanocrystals from a hexagonal structure to a cubic body-centered structure. In nanocomposites (CoFeZr)x (MgF2)100-x, the value of magnetic percolation Хс = 30 coincides with the formation of nanocrystals: below this value х<30 nanocomposites exhibit superparamagnetic properties, and at large values х> 30 become soft magnets with a maximum value of the coercive force Hc <30 Oe.

Biography

Artical Title: The effective cold fusion energy production realization on base of the planar X-ray waveguide-resonators use

Abstract

The main intricate and energy outlaying problem for realization of nuclear fusion reactions is the Coulomb barrier overcoming, which hinders to the direct nuclear interaction. In thermonuclear apparatus the barrier overcoming is effected by increasing of ions kinetic energy in ionized ensemble. This approach competence to the nuclear fusion reactions realization is beyond questions. A.D. Sakharov and Ya.B. Zheldovich pointed on the principle possibility of alternative approach to the nuclear fusion reaction realization without high temperature application. The idea of cold nuclear fusion was implemented by I.S. Filimonenko. Moreover, the cold nuclear fusion or nuclear transmutation phenomenon is beyond questions, too. However, the magnitude of cold nuclear fusion effect is smaller as the expected one on some hundreds thousands times. Our work proposes an alternative approach to the cold nuclear fusion realization on base of the radiation fluxes waveguide-resonance propagation phenomenon consequence and the wave-corpuscle dualism principle. Our experimental studies showed that the planar extended slit clearance transports X-ray characteristic radiation fluxes without attenuation when its width is smaller as the radiation coherence length half (L/2=02/2). This fact was interpreted as the new phenomenon discovery: the waveguide-resonance propagation of radiation fluxes or the radiation superfluidity. The phenomenon is characterized by appearing of the uniform interference field of radiation standing waves. Devices functioned in frame of the phenomenon were called as planar X-ray waveguide-resonators (PXWR). Study of there devices properties showed that independent radiation fluxes can interact in some conditions in result of mutual influence of uniform interference fields of radiation standing waves excited by these fluxes. Owing to the wave corpuscle dualism principle the radiation standing wave uniform interference field can be excited by particles beams with zero rest mass, too. This hypothesis found own experimental confirmation in investigations of low energy neutrons fluxes propagation peculiarities. Analogical interference fields can be formed for atomic and molecular fluxes. Then it will be needed to find conditions for there fields interaction. The suggesting approach allows to evade the Coulomb barrier.

Biography

Artical Title: Optimum stimulation period for pulse thermography

Abstract

António Ramos Silva, holds a Masters and a PhD in Mechanical Engineering from University of Porto, Faculty of Engineering (2010 and 2016 respectively) and a degree in Mechanical Engineering from Porto Polytechnic Institute. He is currently Professor at the Faculdade de Engenharia da Universidade do Porto (Portugal) and a researcher at INEGI - Institute of Science and Innovation in Mechanical and Industrial Engineering.

Biography

Artical Title: On the question of material selection and design options analysis for a centrifugal fan impellers

Abstract

The comparative stress analysis of various design options of the radial blower impellers used in conveyor dryer for fine-grained raw materials is presented. Several popular materials that can be used for the impeller manufacturing are considered. Finite Element Method (FEM) has been used to evaluate the stresses and strains of impeller within the operational speed range and to select the appropriate material. An advantage of using steel with higher impact toughness for the manufacturing of the fan impeller has been shown. Such materials allow to have greater resistance to shock loads during abrupt starts or stops, hitting foreign objects, etc. Analysis shows advantages of impeller design with central disk. The maximum operational rotation speed for this design is 1135 min-1 according to the yield strength with 15% safety factor, while for basic design without central disk is 1225 min-1. The maximum stress for this impeller design is slightly higher among competitors in blades slot for central disk fitting, but the overall stresses are greatly decreased, especially in contact edges with hub and shroud (by 22-38%) and blades bending deformation is reduced by 51%. It is shown that the most effective material option from the considered ones for impeller manufacturing is Hardox 450 steel. Aluminium alloy 6061-T6 demonstrates worse results. Using this alloy is limited in practice, because it made it impossible to operate in high temperature conditions. However, the advantage of using aluminium alloy is the possibility of significant lightening of the impeller while maintaining high strength parameters. The worst strength performance has impeller made from ASTM A36 steel. In design practice it is worth mentioning that Hardox steels have many competitors on the global market. These competitors have almost the same quality indicators and the choice of material is significantly dependent of its availability and price in specific region. Finally the rational choice depends on operating conditions and required fan performance. The performed research helps better understanding possible week points in different impeller design options and cause of potential failures of the centrifugal fans as well; hence, to improve reliability of such equipment engaged in various industrial plants.

Biography

Artical Title: Simulation of quasi-brittle fracture

Abstract

Perfectly brittle or just fragile destruction occurs without plastic deformation. Quasi-brittle fracture involves the presence of a plastic zone in front of the crack edge. Purpose: to describe the factors that determine crack resistance in quasi-brittle fracture. It was assumed that the stress-strain state near the crack tip in quasi-brittle fracture can be described on the basis of: a) known numerous experimental observations, namely: at a certain stage of loading plastic deformations are localized in two, symmetrical with respect to the crack plane, bands (straight lines) of fluidity; b) the assumption that the stress-strain state near the crack tip is adequate to the stress state of the soft layer, in both cases the development of plastic deformations is maintained by neighboring areas where the yield strength is not reached; c) radiographic studies of the newly formed fracture surface, which allow to determine the energy costs of quasi-brittle fracture [8], the proposed formulaК_(1с ) = 0,5σв (3h0)1/2, де σв [МРа] – temporary resistance to destruction; h0 [m] is the height of the irregularities of the newly formed surface. In this paper, we propose the conclusion that a detailed description of the stress-strain state near the top of the separation crack under conditions of plane deformation is not mandatory. Destruction by crack propagation is unambiguously determined by the coordinates of points A and B. Most likely the coordinates of the points are as follows:А(0;σ0,2); В(х0;σut), де σ0,2 – is the conditional yield strength [MPa]; σut - maximum, theoretical strength [MPa]; х0 = k (σut - σ0.2) [m]. Determining the proportionality factor k requires additional research. If σ0.2 = σut , then there is absolutely fragile destruction. As the yield strength σ0,2 increases with decreasing temperature, the fracture becomes more brittle.

Biography

Artical Title: Behavior of power fractional kinetics in condensed matters

Abstract

Kinetics of processes in condensed matters may be expressed in the form of ac frequency spectra of real and imaginary components (in the frequency domain) or in the form temporal decay after abrupt termination of exciting steady state field (in the time domain). Universal relaxation law is characterized by fractional power dependence of real and imaginary component of ac response with the same exponent 0 < n < 1 and widely observed in different classes of materials like amorphous glasses, ceramics, poly-crystalline and single crystals. In this report dispersive media means a system consisting of dynamical pieces characteristic times of which are distributed over wide temporal range according to fractional power law. One of the interesting feature of power dispersive solids are unexpectedly high relative dielectric constant let them name as colossal dielectric constant materials. There are a few models explaining their huge values, but they aren’t directly related to power fractional dispersion. The aim of this report is to describe behavior of power fractional kinetics on temperature and stress on spectra with exponent n within the range of about 0.7-0.9, formulate the kinetics features and universality in temperature and stress dependencies. Character of temperature behavior of power dispersive systems has been considered depending on a range of exponent n. The model of temperature behavior of dispersive systems is based on thermally activated behavior of efficient dipoles with different relaxation times. According to the model universality of temperature behavior of medium dispersive system has been described. Strong stress dependence of medium dispersive systems has been revealed. The proposed model shows that increase of real and imaginary parts of complex relative dielectric constant is accompanied with decrease of exponent n with increasing uniaxial stress. Sensitivity of parameters B and n of dielectric spectra and parameters of effective dipoles on uniaxial stress has been estimated for high-resistivity GaSe layered crystals.

Biography

Artical Title: Casting laser liquid phase joining as a method of producing multi layered composites

Abstract

In modern production, the use of one or another method for obtaining layered composite materials is determined by the properties of the starting materials, the shape of the manufactured metal products, the conditions of its operation and the methods of processing products. Methods for manufacturing layered composites can be classified based on the nature of the processes at the interface between the components: metallurgical, diffusion, or adhesive. The strongest connection occurs under the conditions of metallurgical processes. However, the size of the transition layer (connection layer) should be as narrow as possible, since otherwise the mixing of the components (especially dissimilar ones) leads to deterioration in the quality of the raw materials used. And, in the end, to a deterioration in the quality of the product as a whole. The solution of this problem is facilitated by the use of a concentrated source of local heating - laser radiation. In the development of previously developed traditional technologies, this work provides for the creation of a new hybrid method of casting-laser processing for the production of bimetallic and multilayer products, which makes it possible to combine the advantages of using concentrated energy sources with traditional foundry technologies for the production and restoration of machine parts. The method allows obtaining significant technical and economic results, of which the most important are: an increase in the service life of machine parts by 2.5 - 6.0 times compared to serial products and a reduction of up to 70 - 80% of the cost of high-alloy expensive materials.

Biography

Artical Title: Microthermometric study of fluid inclusions from the Penjom, Tersang and Selinsing Orogenic gold deposits, peninsular Malaysia

Abstract

Ore‐forming fluids in the auriferous district of the Central gold belt in Peninsular Malaysia were investigated for their temperature, salinity, and relationship to the surrounding geology. Field work conducted at mine sites allowed sampling quartz vein specimens which were mounted and polished to make fluid inclusion sections prior to petrography and microthermometry. Cooling and heating experiments were carried out using the Linkam TH600 heating-freezing stage at the Centre for Ore Deposit, University of Tasmania, Australia. Homogenisation temperatures of quartz-hosted fluid inclusions range from 210 to 348°C (Tersang), between 194 and 348°C (Selinsing), and from 221 to 346°C (Penjom). Salinities range from 2.41 to 8.95 wt % NaCl (Tersang), between 1.23 and 9.98 wt % NaCl (Selinsing), and from 4.34 to 9.34 wt % NaCl (Penjom). Laser Raman Spectroscopy indicated that at the Tersang gold deposit, most inclusions are either pure or nearly pure CO2‐rich (87–100 mol %), except for one inclusion, which contains CH4 gas (13 mol %). In addition, at Selinsing, most inclusions are CO2‐rich (90-100 mol %). However, an inclusion was found containing minor N2 (5 mol %) and CH4 (5 mol %). Additionally, at the Penjom gold deposit, most fluid inclusions are CO2‐rich (91–100 mol %), whereas one fluid inclusion is N2‐rich (100 mol %) and another one has minor N2 (5 mol %) and CH4 (5 mol %). Microthermometric data shows an isothermal mixing of hydrothermal fluids. The three deposits have CO2‐rich fluids indicative of metamorphic origin. Field relationship shows a spatial distribution of sandstone and carbonaceous black shales with magmatic rocks, such as rhyolite, rhyolite‐dacite, and trachyte‐andesite at the Tersang and Penjom orogenic gold deposits indicative of involvement of magmatic fluids in the system.

Biography

Artical Title: Graphene origami based metamaterials

Abstract

Mechanical metamaterials have emerged as a new class of functional materials with unusual material properties. An important example of mechanical metamaterials is auxetic material with tunable negative Poisson’s ratio. Such materials are attaching considerable interests due to their promising applications in various engineering sectors. Although enormous studies have been performed to present negative Poisson’s ratio properties in various materials, research work on the auxetic behavior of graphene reinforced metal nanocomposites is still at its early stage. The present work develops a graphene origami structure to tune the negative Poisson’s ratio in graphene reinforced copper nanocomposites. Extensive molecular dynamics simulations are conducted to study the tuning mechanism of negative Poisson’s ratio of graphene/Cu composites. The adaptive intermolecular reactive bond order (AIREBO) potential, embedded atom method (EAM) potential, and Lennard-Jones (LJ) potential are employed to simulate the C-C covalent interaction of graphene, the interactions between Cu atoms, and the van der Waal (vdW) interactions between graphene and Cu matrix, respectively. Various graphene origami structures, including Miura pattern, Waterbomb pattern, and Yoshimura pattern, are formed with the assistance of surface hydrogen functionalization in predesigned areas of the graphene sheet. The shape of the graphene origami can be tuned and controlled by changing the content and width of H adatoms in the creases. Afterwards, the designed graphene origami is embedded into a Cu matrix to achieve the tunability of negative Poisson’s ratio. Our results demonstrate that a higher content of graphene origami in composites can lead to a larger negative Poisson’s ratio. In addition, the ambient conditions have considerable effects on the auxetic behaviors of graphene/Cu metamaterials. A greater negative Poisson’s ratio of composites can be achieved in higher temperature and pressure environments. It is also found that bigger folds in graphene origami can help the metal metamaterial to reach more efficient auxetic properties.

Biography

Artical Title: Utilization of supercritical carbon dioxide for development of advanced pharmaceutical formulations with valsartan and carvedilol

Abstract

Supercritical carbon dioxide (scCO2) is a green medium that allows production of solvent-free formulations without the use of excipients and organic solvents. In this study, it was used for processing of valsartan and carvedilol in order to produce formulations that will increase bioavailability of drugs. Both valsartan and carvedilol are cardiovascular drugs that have low bioavailability (around 20-30%). In addition, biodegradable and biocompatible pharmaceutical polymers (Soluplus®, hydroxypropyl methylcellulose acetate succinate, and Eudragit® E100) were tested as carriers of valsartan and carvedilol. It was shown that proposed one-step process performed at 30 MPa during 2 h allowed for plasticization of all tested polymers. All characterization tests (SEM, FTIR, DSC, XRD) indicated that drugs were dispersed in polymeric carriers, whereby amorphous solid dispersions with density in the range from 327 to 667 kg/m3 and porosity from 12 to 78 vol% were obtained. Controlled release of drugs was influenced by solubility of polymers in the tested release medium that simulate body fluids (HCl and PBS). Dissolution of valsartan and carvedilol from formulations was increased compared to untreated drugs. Proposed process enabled preparation of two-component system that has advanced properties compared to pristine components as well as commercial formulations. The obtained results provide framework for future development of environmental friendly method for production of drug delivery systems.

Biography

Artical Title: Restraining oxygen release and suppressing structure distortion in single-crystal Li-rich layered cathode materials

Abstract

Li-rich oxides can be regarded as the next-generation cathode materials for high-energy-density Li-ion batteries since additional oxygen redox activities greatly increase output energy density. However, the oxygen loss and structural distortion induce low initial coulombic efficiency and severe decay of cycle performance, further hindering their industrial applications. Herein, the representative layered Li-rich cathode material, Li1.2Ni0.2Mn0.6O2, is endowed with novel single-crystal morphology. In comparison to its polycrystal counterpart, not only can serious oxygen release be effectively restrained during the first oxygen activation process, but also the layered/spinel phase transition can be well suppressed upon cycling. Moreover, the single-crystal cathode exhibits the limited volume change and persistent presence of superlattice peaks upon Li+ (de)intercalation processes, resulting in enhanced structural stability with absence of crack generation and successive utilization of oxygen redox reaction during long-term cycling. Benefiting from these unique features, the single-crystal Li-rich electrode not only yields a high reversible capacity of 257 mAh g−1, but also achieves excellent cycling performance with 92% capacity retention after 200 cycles. These findings demonstrate that the morphology design of single crystals can be regarded as an effective strategy to realize high-energy density and long-life Li-ion batteries.

Biography

Artical Title: Laser-induced graphene-based electrochemical biosensor for clinical application

Abstract

Laser-induced graphene (LIG) has recently received increasing attention due to its simple fabrication and low cost. This study reports a flexible laser-induced graphene-based electrochemical biosensor fabricated on a polymer substrate by the laser direct engraving process. For this purpose, a 450 nm UV laser was employed to produce a laser-induced graphene electrode (LIGE) on a polyimide substrate. After the laser engraving of LIGE, the chitosan-glucose oxidase (GOx) composite was immobilized on the LIGE surface to develop the biosensor for glucose detection. It was observed that the developed LIGE biosensor exhibited good amperometric responses toward glucose detection over a wide linear range up to 8 mM. The GOx/Chitosan-modified LIGE biosensor showed high sensitivity of 43.15 µA mM−1 cm−2 with a detection limit of 0.431 mM. The interference studies performed with some possible interfering compounds such as ascorbic acid, uric acid, and urea exhibited no interference as there was no difference observed in the amperometric glucose detection. It was suggested that the LIGE-based biosensor proposed herein was easy to prepare and could be used for low-cost, rapid, and sensitive/selective glucose detection.

Biography

Artical Title: Organic photodiode integration on Si substrate beyond 1000 nm wavelength

Abstract

Near infrared (NIR) and shortwave infrared (SWIR) image technologies are of interest for many emerging applications. Above 1100 nm, Si is blind and has no sensitivity. Emerging optoelectronic materials, such as small molecules, polymer, and organic-inorganic hybrids have been demonstrated as promising alternatives to traditional inorganic photodetectors for NIR and shortwave infrared (SWIR) imaging. Among photodetector technologies, organic photodetectors (OPDs) are groundbreaking light sensors with unique photon-to-electron responses at various wavelengths that offer limitless flexibility in field applications due to the tunable design of organic semiconductors. Organic photodiode integration on the Si readout circuit offers a solution for extending the sensitivity beyond 1000 nm. In this work, we report the way to integrate organic photodiode on Si substrate with metals that are CMOS process compatible as bottom electrodes, such as titanium nitride (TiN), tungsten (W), and aluminum (Al). We report high-efficiency NIR sensor enabled by employing TiN and W as bottom electrodes, with an external quantum efficiency (EQE) of ~50% at 940 nm and ~70% at 1030 nm, a dark leakage current density of 15 nA/cm2, a bandwidth of 15 kHz at -4V, and a dynamic range (DR) of ~100 dB are achieved. Low resistivity and inert properties of TiN make it forms a good interface with organic active layer, leading to an ideal bottom contact metal for organic photodiode when integrated on Si substrate. This work highlights the importance of the interface between the bottom electrode and OPD, which needs to be well considered for OPD and Si-CMOS integration with a CMOS compatible process flow, offering the possibility to extend the sensitivity of CMOS image sensor beyond 1000 nm, which can be applied in high-performance NIR/SWIR low-cost imaging systems.

Biography

Artical Title: Boost antimicrobial effect of CTAB-capped NixCu1-xO (0.0 ≤ x ≤ 0.05) nanoparticles by reformed optical and dielectric characters

Abstract

Chemical doping and coating have been considered as efficient semiconductor physics strategies to modulate the physical, chemical, and biological properties of materials for the required applications. In this study, cetyltrimethylammonium bromide (CTAB) stabilizer capped nickel doped cupric oxide (NixCu1-xO) nanoparticles (NPs) with different doping concentrations (0.0 ≤ x ≤ 0.05) were synthesized via a one-step rapid and low-cost solvothermal synthesis route. The as-synthesized CTAB-capped NixCu1-xO NPs have been sightseen for their structural/morphological, optical/dielectric, and antimicrobial properties using XRD/SEM/TEM, FT-IR/UV-visible/Impedance spectroscopies, and Agar well diffusion method, respectively. Relevant results show enhanced optical, dielectric and antimicrobial properties with Ni doping due to the smaller size effect. Importantly, in vitro examination, the antimicrobial activity of the grown NPs was evaluated against four microbial species, exhibits that the CTAB-capped Ni-doped CuO NPs possess a command antimicrobial toxicity to Staphylococcus aureus (25923-ATCC), Klebsiella pneumoniae (700603-ATCC), and Escherichia coli (25922-ATCC) and an intermediate performance towards Candida albicans (24433-ATCC). The minimum inhibitory concentration (MIC) assay for the obtained CTAB-Ni0.05Cu0.95O sample upon S. aureus or K. pneumoniae pathogens reaches extremely as low as 5 μg-ml-1 for all reported CuO NPs. The improved dose-dependent antimicrobial effect has been found to be strongly dependent on the particle size, surface morphology, elemental compositions, and surface bio-functionality of the catalytic nanomaterials. Additionally, Ni-dopant, CTAB-stabilizer, and binding of Cu+/Cu2+ ions with respiratory enzymes collectively produce an excess amount of reactive oxygen species (ROS) in the bacterial culture medium, which determines a predominant antibacterial mechanism for bacterial cells damage. Overall, these inorganic (NixCu1-xO) NPs with antimicrobial cationic surfactant (CTAB) have advantages to use as a functionalized disinfection nano-agent to control the microbial infections in the health care sector together with various electronic and photonic medical diagnoses.

Biography

Artical Title: Transformation heat transfer and thermo-hydrodynamic cloaks for creeping flows: Manipulating heat fluxes and fluid flows simultaneously

Abstract

Although the subject of thermal cloaking has attracted extensive academic attention, most pioneering studies have so far focused on thermal conduction systems or thermal convection in the porous media, which prevents the object from moving. Here, we have discovered that Stokes equations and the energy transport equation do abide by the coordinate-transformation invariant theory if the former is replaced with the pressure Laplace equation. This discovery enables us to rightfully take advantage of the merit of this theory and to analytically design metamaterial thermo-hydrodynamic cloaks. More importantly, since our designed cloaks depend on the viscosity and the thermal conductivity of background flows as well as geometries of cloaks only, but not on boundary conditions of background flows, they can be continuously utilized when objects travel in the media under realistic flow conditions. Besides, we also suggest experimental demonstrations to show the feasibility of our design. Finally, it is our hope that numerical data obtained in the proposed study can (1) facilitate the realization of lab experiments as well as help them identify characteristic flow and thermal parameters, and (2) serve as a stepping stone to further explore other thermo-hydrodynamic metamaterial devices.

Biography

Artical Title: 2D glassy-graphene device arrays with photodetection and VOC sensing capabilities

Abstract

Multifunctional devices are of great interest for integration and miniaturization on the same platform, but simple addition of functionalities would lead to excessively large devices. Here, the photodetection and chemical sensing device is developed based on novel 2D glassy-graphene1,3 that meets similar property requirements for the two functionalities. An appropriate bandgap arising from the distorted lattice structure enables glassy-graphene to exhibit similar or even improved photodetection and chemical sensing capability, compared to pristine graphene. Due to strong interactions between glassy-graphene and the ambient atmosphere, the devices are less sensitive to photoinduced desorption than graphene. Consequently, the few-layer glassy-graphene device delivers positive photoresponse, with a responsivity of 0.22 A/W and specific detectivity reaching 1010 Jones under 405 nm illumination. Moreover, the intrinsic defects and strain in glassy-graphene can enhance the adsorption of analytes, leading to good chemical sensing performance. Specifically, the extracted signal-to-noise-ratio (SNR) of the glassy-graphene device for detecting acetone is 48, representing more than 50% improvement over the graphene counterpart. Additionally, bias voltage and thickness dependent VOC sensing features are identified, indicating the few-layer glassy-graphene is more sensitive. This study successfully demonstrates the potential of glassy-graphene for integrated photodetection and chemical sensing, providing a promising solution for multifunctional applications further beyond.

Biography

Artical Title: Performance of OLED under mechanical strain: A review

Abstract

OLEDs with convenient portability, low power consumption, and mechanical flexibility have successfully demonstrated their wide range of applications in display, lighting, and medical devices. With the biological requirement and continuous development of electronic technology, the OLEDs have opened up new possibilities for wearable electronic devices. Plentiful reports have revealed the progress of OLED devices with excellent performance of mechanical strain, involving flexible electrodes, processing technology, and advanced fabrication. In this review, the OLED processing methods are systematically discussed, and the development of flexible electrodes has been focused in terms of mechanical strain. In addition, the OLED performance with flexible electrodes also is described. The review provides a comprehensive understanding of OLEDs that can withstand the mechanical strain and achieve commercial maturity.

Biography

Artical Title: Method and mechanism research on highway asphalt pavement hot in-place and central plant recycling based on microwave and hot air combining multi-dimensional low temperature heating

Abstract

The recycling of waste asphalt pavement materials is a major problem faced by countries all over the world. Our country produces as much as 300 million tons every year, and long-term stacking takes up a lot of land and pollutes the environment. In 2021, the State Council clearly pointed out to promote the resource utilization of waste roads, asphalt and other materials. Hot recycling is one of the important ways. Traditional Hot recycling methods uses high temperature heating to cause asphalt aging and carbonization on the surface of the aggregate, which affects the fusion of new and old materials and asphalt, and is not conducive to recycling. Moreover, traditional hot in-place recycling has limited grading adjustment, large environmental pollution, and low quality of the recycled asphalt pavement; although the central plant recycling can adjust the grading greatly, it is limited by traditional heating. High-quality recycling is still not high, increasing transportation costs. The microwave regeneration heating efficiency is high and will not cause the asphalt to age. The regenerated asphalt mixture has better high temperature stability, crack resistance and fatigue resistance, but its heating cost is higher. Therefore, the research group proposed the method and mechanism research on highway asphalt pavement hot in-place and central plant recycling based on microwave and hot air combining multi-dimensional low temperature heating, from the heating method, mechanism and thermal regeneration method to jointly solve the current problems of thermal regeneration, in line with the national concept of developing a green and low-carbon circular economy, it has a clear leading and pioneering, innovative asphalt pavement recycling technology.

Biography

Artical Title: Optimized energy harvesting approach: Infra-red photo voltaic cells

Abstract

Optimal energy solution for any specific requirement depends on geographical location, simplicity of mechanism, technical stability, energy harvesting capabilities, and cost. Wind energy though relatively cheap, but termed sporadic due to non-consistent conditions and periodic maintenance requirement for the extraction mechanisms. Solar energy is a rich energy source with the possibility of exploiting anywhere during day time, and a relatively cheap & noiseless renewable energy source. Though solar energy is pollution-free with less impact on the eco-system, it does have limitations, mainly due to its intermittent nature, attributed to sun availability for specific hours (e.g. during daytime only) and the energy conservation efficiency may be considerably low. Sunlight being a shallow source of energy does require a large area for the collection of a considerable amount of energy. We grasped the idea from MIT cutting edge research focused to harness IR spectrum portion within the solar spectrum. In this research work, we have proposed the design of a multifunctional and relatively efficient energy harvesting mechanism that can also work in the near-infrared region. The design is based on nano-meter sized optical waveguide imprints on micrometer sized conventional window glass ensuring concentrated photon absorption in the infra-red region. Besides conventional SOI optical waveguides, chalcogenides is also implemented. The dispersive and losses effects calculations provide further knowledge about the state of the window panes transparency / opacity. Besides leading towards a simple way of energy harvesting; the basic platform (window panes) can still be used for enjoying sunlight inside the rooms as well. The research will open more avenues in the field of photo-voltaic power generation.

Biography

Artical Title: Structural behavior of reinforced ultrahigh performance concrete under uniaxial loading

Abstract

Ultrahigh performance concrete (UHPC) has recently been promoted for many applications in the construction industry due to its superior mechanical properties including the high compressive strength and the sustained post-cracking tensile strength as well as its pronounced durability. UHPC is mostly preferred to exhibit a strain-hardening tensile response in which multiple micro-cracking characterizes the response until reaching the peak tensile capacity. Such feature results in a large deformation capacity (ductility) and gradual cracking. On a material level, UHPC has been found to demonstrate high ductility and slow failure pattern. However, on a structural level, when combined with rebar reinforcement, the response of UHPC has not been clearly established, and some incidents of quick and brittle collapses have been witnessed, particularly under shear loading where a single macro-crack governs the failure in a very abrupt manner. Hence, the tensile behavior of reinforced UHPC members under tension still requires further research. The tension stiffening effect, the cracking patterns under different fiber content ratios and reinforcement ratios, and the ductility need more elucidation. To this end, this study aims at investigating the behavior of reinforced UHPC under uniaxial loading with regard to the effect of fiber content ratio and reinforcement ratio. The fiber content ratio used in this study was 1, 2, 3.5% in volume, and the reinforcement ratio was 0.97, 1.4, 2.18 and 3.41%. The effects of these parameters on the bearing capacity, ductility and cracking pattern are explored. In addition, an analytical model for describing the response of a UHPC tension member is proposed and simplified expressions for calculating the micro-cracks spacing and macro-crack spacing are provided. The response of UHPC tension members can be extended to describe the response of the tension chords in flexural members.

Biography

Artical Title: Plasticity and reprocessing of dynamic covalent polymer networks

Abstract

Ning Zheng received her B.S. (2014) and Ph.D. (2019) from Zhejiang University, China, where she continued to work as a postdoctoral research associate during the following two years. In 2017, she served as a visiting scholar at Northwestern University, USA. She is currently a faculty member in the College of Chemical and Biological Engineering at Zhejiang University. Her research interests include dynamic covalent polymer networks and shape memory polymers.

Biography

Artical Title: Gardens of mental peace: A literary perspective of horticulture

Abstract

It is long held dogmas that contact with nature (landscape, vegetation and water) ameliorates anxieties and fetch general healthcare benefits. Throughout its life, an individual enmeshes within a dynamic confliction of the natural and artificial environment, social life and consciousness. Within this confliction, the well-being rests on the availability of a perfect environment offering peace of mind and happiness. Nerve-shaken and tired people find wilderness, mountains, forests and meadows as fountains of mental peace and happy life. Thus, mental exhaustion drives a thrust to contact with nature to nourish our physical and physiological needs, and comfort. Naturalized spaces and gardens present a powerful symbolic platform for best manipulations in literature. In addition to nourishing exhausted minds, company of plants does offer nice selection of words for poets and literary men. Gardens as rhythmical manifestation of nature serve the best source of linking literature with the horticulture and this can be the best topic to study so that the upcoming generations can be connected with plants in order to secure the fading love for nature in this materialistic world. Therefore, we can hypothesize that a sophisticated use of word either in literature or in poetry is imperfect unless accompanied by nature.

Biography

Artical Title: MnS-nanoparticles-decorated three-dimensional graphene hybrid as highly efficient bifunctional electrocatalyst for hydrogen evolution reaction and oxygen reduction reaction

Abstract

The search for renewable energy resources has attracted considerable research interests in electrochemical reactions of hydrogen evolution reaction (HER) and oxygen reduction reaction (ORR) that are essential for fuel cells. Earth-abundant, eco-friendly and cost-effective transition metal compounds are emerging candidates as electrocatalysts in these reactions. Herein, we report the growth of manganese sulfide nanoparticles on three-dimensional graphene, through an easy, progressive successive ionic layer adsorption and reaction (SILAR) method, where manganese sulfide nanoparticles (MnS-NPs), diameter of 4-5 nm are homogeneously decorated on the 3D graphene matrix. SILAR has been proven to be a facile, low-cost and eco-friendly method to grow nanomaterials on 3D conductive support and it is clearly different from previous MnS synthetic routes such as spray pyrolysis, microwave irradiation, chemical bath deposition, solvothermal and hydrothermal that required time-consuming procedures and harsh conditions. Transition metals based sulfides are the most extensively studied among nanostructured electrocatalysts for overall alkaline water splitting, with the advantages of being widely available, inexpensive, chemically stable, and highly active yet with low conductivity and sensitivity to half-cell processes issue. Importantly, the active sites of transition metal sulfides based electrocatalysts are nearly always the metal atoms, while exposed S atoms play a vital direct role in the HER process via increasing the number of active sites and changing the coordination environments of adjacent metal atoms. Moreover, the indirect role of S atoms in the HER provides locations for hydrogen adhesion and separation when metal atoms act as active sites. Owing to such beneficial of transition metal sulfides based electrocatalysts with carbon based supportive materials, as formed ,MnS@3DG has indicated marvelous synergistic effects between metal sulfide based nano particles and high surface areal graphene foam with such noticeable intimacy that has markedly improved conductivity to enlist the MnS@3DG nanocomposite as efficient bifuntional electrocatalyst in alkaline electrolyte showing an η HER of just 274 mV at a current density of 10 mA cm-2, much smaller than that of the bulk MnS (800 mV). Even when the current density is increased to 40 mA cm-2, the overpotential is still low as 350 mV. While the oxygen reduction onset potential was 0.9 V (vs. RHE), and the peak potential was 0.75 V (vs. RHE), thus achieving a bifunctional catalytic performance superior to most of the reported manganese-based electrocatalysts in HER and ORR.

Biography

Artical Title: Atomic scale study of grain boundaries in low-symmetry two dimensional ReS2

Abstract

Grain boundaries (GBs) are significant microstructures that dominate properties of polycrystalline two-dimensional (2D) materials. Low-symmetry monolayer rhenium disulfide (ReS2), which belongs to the triclinic crystal system and displays abundant anisotropic properties, provides an ideal platform to investigate diverse configurations of GBs and their orientation-dependent characteristics. Here, we combine aberration-corrected scanning transmission electron microscopy and density functional theory (DFT) calculations to investigate the atomic configurations, electronic band structure and facture mechanics of both atomically stitched and overlapping GBs in chemical vapor deposition-grown polycrystalline ReS2 monolayers. Our results provide fundamental insights into the impact of GBs on material’s electronic and mechanical properties, thus helping establish a more comprehensive understanding between the macroscopic performance and the microscopic structure of 2D materials.

Biography

Artical Title: Soil carbon supplementation: Improvement of root-surrounding soil bacterial communities, sugar and starch content in tobacco (N. tabacum)

Abstract

Soil carbon supplementation is known to stimulate plant growth by improving soil fertility and plant nutrient uptake. However, the underlying process and chemical mechanism that could explain the interrelationship between soil carbon supplementation, soil micro-ecology, and the growth and quality of plant remain unclear. In this study, we investigated the influence and mechanism of soil carbon supplementation on the bacterial community, chemical cycling, mineral nutrition absorption, growth and properties of tobacco leaves. The soil carbon supplementation increased amino acid, carbohydrates, chemical energy metabolism, and bacterial richness in the soil. This led to increased content of sugar (23.75%), starch (13.25%), and chlorophyll (10.56%) in tobacco leaves. Linear discriminant analysis revealed 49 key phylotypes and significant increment of some of the Plant Growth-Promoting Rhizobacteria (PGPR) genera (Bacillus, Novosphingobium, Pseudomonas, Sphingomonas) in the rhizosphere, which can influence the tobacco growth. Partial Least Squares Path Modeling (PLS-PM) showed that soil carbon supplementation positively affected the sugar and starch contents in tobacco leaves by possibly altering the photosynthesis pathway towards increasing the aroma of the leaves, thus contributing to enhanced tobacco flavor. These findings are useful for understanding the influence of soil carbon supplementation on bacterial community for improving the yields and quality of tobacco in industrial plantation.

Biography

Artical Title: Study on soybean oil based thermosetting resin and its composites

Abstract

Environmentally friendly polymers based on biomass have been attracting much attention, and one of hot concerns is making low-priced soybean oil into polymers with higher values. Each fatty acid chain in the triglyceride mixture of soybean oil contains a single or multiple double bonds. Epoxidized soybean oil (ESO) with a higher reactivity, which can be used in the synthesis of high bio-based polymers, is obtained through an epoxidation process of double bonds in soybean oil. In our work, the evolution of the curing process of epoxidized soybean oil was simulated by molecular dynamics simulation, and the thermomechanical properties of epoxidized soybean oil cured by a series of different amine and anhydride were predicted, and the relationship between structure and properties was established. Then thermoset reins with more than 90% bio-based carbon content were prepared by the curing reaction between ESO and a derivative of rosin acid, maleopimaric (MPA). Curing behavior and structure-activity relationship were also studied. Acrylated epoxidized soybean oil (AESO) was prepared by ring-opening reaction of ESO with acrylic acid, and an innovative biobased UV coating synthesized from acrylated epoxidized soybean oil and poly(octamethylene maleate (anhydride) citrate) was developed. Carbon nanotubes were modified with poly(acrylated epoxidized soybean oil) to improve their dispersibility in polymer matrixes to obtain ESO-based nanocomposites with good performance. These results could provide new approaches for the preparation of novel bio-based thermoset resins with excellent performance.

Biography

Artical Title: New hydrogen atom model and radiation absorption mechanism

Abstract

In Bohr model and Schrodinger equation, only the spherically symmetric Coulomb potential in hydrogen atom is considered, but the Lorentz potential caused by proton and electron spin and orbital magnetic moment is not considered. We find that the Lorentz force and Coulomb force coexist, that the electron moves along a circular or elliptical orbit, that the radius of the ground state orbit is twice the Bohr radius and that the rotation frequency is half the Bohr frequency. The "half frequency" problem that perplexed Bohr's life is solved, and the details and mechanism of radiation absorption and release are given. Using the standing wave condition, we obtain the quantization results of the energy levels. It is revealed and proved that the electronic velocity in the atom and molecule is a constant, and the orbital energy level only depends on the rotation frequency, but has nothing to do with the velocity. The source and physical significance of the fine structure constant and Planck constant are given.

Biography

Artical Title: Study on composite materials for electro-hydraulic transmission

Abstract

In order to reduce the weight and vibration of Electro-hydraulic Transmission, the composite gear was studied, a new type of steel phenol composite transmission gear was put forward, and its optimal design was given. In this method, the polymer composite was placed between the steel tooth and the central hub area along the radial direction of the gear, so as to reduce the vibration transmission rate from the tooth to the hub and the weight of the gear train. In order to minimize the weight of the composite gear, the optimum size of the radial composite zone of the gear was calculated by considering the fatigue strength of steel and composite materials. The results show that, compared with pure steel gears, the average sound pressure levels of optimized and un-optimized composite gears are reduced by 7.2% and 4.6%, respectively, and the average acceleration is reduced by 15.3% and 12.0%.

Biography

Artical Title: Novel functional semiconductor-Ionic materials

Abstract

Recent research and development on semiconductor-ionic materials (SIMs) with superionic conduction as alternative electrolytes lead to a new trend in low temperature solid oxide fuel cell (SOFC) and proton ceramic fuel cell (PCFC). This can be traced from a radical new invention of single-layer fuel cell (SLFC) or electrolyte-free fuel cell (EFFC), i.e. one semiconductor-ionic component instead of anode/electrolyte/cathode three components can realize fuel cell technology. Such SIMs can integrate the functionalities of fuel cell’s anode, electrolyte, and cathode into one component. This could represent a major progress and breakthrough in fuel cell science and technology and lay grounds for a new era of fuel cell R&D and commercialization. The SOFC technology depends on the electrolyte, yttrium stabilized zirconium (YSZ), but it requires a temperature over 700°C to operate properly due to requirement of sufficient ionic conductivity. The situation could now be improved if replacing YSZ with a SIM with high ionic conductivity to develop semiconductor-ionic fuel cells (SIFCs). The SIFC may demonstrate high performance at temperatures well below 550°C. Current SIMs may be classified into three types I) Single phase semiconductors, e.g. perovskite and layered structured oxides, SmNiO3, LiCoAlO2, LiNiFeO2, etc. These semiconductors have shown metal or high electronic (hole) conductivity with narrow or zero bandgap to experience a transition to ionic conduction by proton insertion from fuel cell operation; II) Wide bandgap materials, typically, oxygen deficit oxides, e.g. fluorite structure CeO2-d. The CeO2-d can change from insulating or electronic conduction to a proton conductor in the fuel cell operation; III) Both semiconductor and ionic conduction form a two-phase heterostructural nanocomposite, where percolation of both electron and ion conducting paths result in comparable or balanced electronic and ionic conduction.

Biography

Artical Title: Image segmentation by phase-field models with local information

Abstract

We proposed an improved phase-field model with local information for image segmentation. In our approach, a new double well potential function containing local contributions is taken into account. The advantages of the new scheme are in two folders. Firstly, the affection of noise could be reduced in image segmentation with intensity inhomogeneity. Secondly, a more stable boundary evolution could be achieved compared with the traditional way. Segmentation results for several different types of images are reported. We compare the segmentation results with the classical model for two-dimensional images. In the segmentation of three-dimensional magnetic resonance brain images, the accuracy comparisons are presented by the Dice and Jaccard similarity coefficients. Compared with the classical model, our model has higher segmentation accuracy and better stability of boundary evolution.

Biography

Artical Title: Synthesis and surface engineering of low-dimensional semiconductors for electronics and energy applications

Abstract

Low-dimensional semiconductors, especially two-dimensional (2D) semiconductors, are considered one of the most promising candidates in the field of microelectronics, optoelectronics, and energy, owing to their atomically thin structure that can mitigate short-channel effects, controllable band gaps, and quantum confinement effect. The synthesis of low-dimensional semiconductors, as well as the use of surface and interface engineering for tailoring the electronic properties are essential to broaden their applications. This report summarizes our research on the synthesis and surface/interface engineering of low-dimensional semiconductors, especially two-dimensional transition metal dihalides (TMDC). Element doping and heterogeneous interface engineering are utilized to adjust their physical and chemical properties in order to realize high-performance electronic devices and new energy devices.

Biography

Artical Title: Applications of a novel general solution to the inhomogeneous spatial axisymmetric problem in functionally graded materials

Abstract

The axisymmetric problem has always been a typical problem in the theory of elasticity, and the inhomogeneous spatial one has an especially wider range of applications. In this work, we present a novel analytical elastic general solution to the inhomogeneous spatial axisymmetric problem. The specific descriptions of inhomogeneity are: Young’s modulus of the material is an arbitrary function of both radius and thickness coordinates, and Poisson’s ratio is considered as a constant. The elastic stress method is applied to obtain a general stress solution and a relatively concise analytical displacement solution, the degenerate forms of which are both consistent with the existing results. Based on the general elastic solution, we study an axisymmetric bending problem of functionally graded circular plates subjected to a transverse loading q_0 r^n (n is an even number, and r is the radius coordinate) and give explicitly analytical elastic solutions to the case of uniform loadings under simply supported and two types of clamped supported conditions respectively. The final analytic solutions correspond well to the existing numerical results. The distributions of explicit elastic fields related to the inhomogeneous parameter reveal the influence of inhomogeneity on the stress and displacement in FGM circular plates intuitively, which makes it possible to control the elastic performance of FGM plates more accurately.

Biography

Artical Title: Atomic insights into synergistic effect of 3D graphene nanoplatelet and carbon nanotube hybrids on the mechanical properties of polymer nanocomposites

Abstract

The unique three-dimensional (3D) hybrid structures of graphene nanoplatelet (GNP) and carbon nanotube (CNT) hybrid filler can improve dispersion and enhance interfacial properties to achieve excellent reinforced polymer composites. Molecular dynamics simulations have been performed to explore the underlying synergistic mechanism of pillared graphene or non-covalent connected graphene and carbon nanotubes (CNTs) on the mechanical properties of polyethylene (PE) nanocomposites. In order to reveal the synergistic effect of the morphology and arrangement of pillared graphene in enhancing the mechanical properties of polymer nanocomposites, the pillared graphene/PE (PG/PE) model were engineered. Moreover, by constructing the pillared graphene model and CNTs/graphene model, the effect of the structure, arrangement and dispersion of hybrid fillers on the tensile mechanical properties of PE nanocomposites was studied. The results show that the pillared graphene/PE nanocomposites exhibit higher Young’s modulus, tensile strength and elongation at break than non-covalent connected CNTs/graphene/PE nanocomposites. The tensile strength, Young's modulus and elongation at break of the pillared graphene/PE composites all increase first and then decrease as the length of the carbon nanotube increases. The multi-layer pillared graphene/PE composites have a higher Young's modulus than the single-layer pillared graphene/PE composites. Compared with CNTs/graphene hybrid, pillared graphene delivers a more significant synergistic effect and this is attributed to the self-supporting mechanism of pillared graphene. The pull-out simulations show that pillared graphene by CNTs has both large interfacial load and long displacement due to the mixed modes of shear separation and normal separation. Additionally, pillared graphene can not only inhibit agglomeration but also form a compact effective thickness (stiff layer), consistent with the adsorption behavior and improved interfacial energy between pillared graphene and PE matrix.

Biography

Artical Title: High aspect ratio contact etching using C6F12O precursor with low global warming potential

Abstract

In the semiconductor industry, the size of nano-electronic devices is getting smaller and more integrated to form complex nanostructures on wafers. In order to manufacture a nano-electronic device, an accurate pattern must first be formed on a silicon substrate. Dry etching technology is mainly used in patterning processes to control the flux of active neutral species and charged particles formed in plasma and to form accurate nano-meter patterns. So far, due to the high chemical reactivity of silicon and fluorine, perfluorocarbon (PFC)-based gas chemistry including CF4, CHF3 and C4F8 has been used for nanopatterning of dielectric contacts. However, PFC gases generally have a high global warming potential (GWP) of over 8,000 and have a significantly negative impact on the ozone layer. Attempts have been made to replace, decompose, and/or recycle PFC gases with high GWP to reduce greenhouse effects in nano-sized electronic devices. For this, it is necessary to use low GWP gas for manufacturing nano-sized electronic devices in industrial fields. Low-GWP precursors exist as liquid sources with low boiling points or at room temperature for easy recovery. Therefore, to overcome the environmental issues in the manufacturing process for nano-sized semiconductor devices, the process applicability of liquid-PFC (L-PFC) gases (i.e., C6F12O, C7F14) should be further studied for fabricating nano-sized devices in advance. In this study, the etching process was performed using C6F12O, one of the precursors with low GWP. In addition, compared the HARC etching characteristics, plasma analysis and surface chemical bonding analysis of the conventional ICP system (13.56 MHz bias generator) and the ICP system with low RF frequency (2MHz) bias generator.

Biography

Artical Title: A study on high aspect ratio contac (HARC) etching process through independent control at low frequency bias using ICP system

Abstract

As the memory semiconductor market has grown rapidly in recent years, demand and technology development for next-generation memory semiconductors such as 3D NAND flash, RAM, and PRAM are required. In particular, in the case of a NAND flash, the structure is changing from a two-dimensional structure to a three-dimensional stacked-type NAND flash structure according to technological development. As the number of layers increases during the 3D NAND flash process, the HARC (High Aspect Ratio Contact) etching process is an essential process. However, as the vertical process is required, the difficulty of the process increases rapidly, and distortion of the etch profile such as necking and bowing occurs. In the next-generation HARC etching process, the concentration of radicals, ions, and ion energies is referred to as the impact key. However, current studies on the HARC etching process show that ion and radical concentrations and ion energies change simultaneously. Therefore, the concentration of radicals, ions and ion energies, the effects of each are not analyzed independently. Therefore, in this study, we propose a methodology that can independently control the concentration and ion energy of radicals and ions according to process parameters. Plasma analysis was performed using optical emission spectroscopy and DLP. This established radical and ion independent control conditions. The HARC etching process was performed according to low frequency (2 MHz) and high frequency (13.56 MHz) under each independent control condition using ICP. Analyze the SiO2 profile shape by scanning electron microscopy (SEM) after the HARC etching process. It suggests the direction of the HARC etching process by analyzing the correlation between ion and radical concentration and ion energy through plasma analysis and etching process results.

Biography

Artical Title: Study of structural, optoelectronic and magnetic properties of Half-Heusler compounds QEuPa (Q= Ba, be, Mg, Sr) using first-principles method

Abstract

The structural, optoelectronic and magnetic properties of the Half-Heusler (HH) compounds QEuPa (Q ¼ Ba, Be, Mg, Sr) in the ground state are investigated from the first principles calculations. Stable optoelectronic and magnetic properties of HH compounds are calculated by the FP-LAPW method implemented in the WIEN2k software. The strong correlation between the Eu/Pa f-states is taken into account when studying electronic properties such as the band structure and density of states (DOS). Based on the band structures of the considered compounds, it can be concluded that they are metallic. The dielectric function ε (ω) obtained for QEuPa HH compounds is used to study optical dispersion and absorption. QEuPa compounds absorb the maximum number of incoming photons in the infrared (IR) region. Significant magnetic moment occurs in these compounds due to the splitting of the Eu-4f7, Pa-5f2 and Pa-6d1 localized orbitals.

Biography

Artical Title: Kinetics and equilibrium study of the adsorption of silver ions by polymeric composites containing zeolite and methacrylic acid

Abstract

Environmental and water pollution caused by heavy metals, especially silver, is considered a threat to humans, ecosystem, and all living species. Therefore, with the development of industrialization, it is a very important effort to remove heavy metals from the environment and wastewaters. For this reason, in the present study, we synthesized two polymeric composites of ethylene glycol dimethacrylate (EGDM), methacrylic acid (MA), and different amounts of zeolite (25 g and 50 g) (PMAZ25 and PMAZ50) by using BPO-DMA initiator system at room temperature (298 K). Fourier Transform Infrared (FTIR) was used to show the presence of functional groups in the synthesized composites, and Thermal Gravimetric Analysis (TGA) was used to test the thermal stability of the copolymeric composites. Batch adsorption method was applied to examine the effect of polymeric composites on silver ion adsorption at different pH values, contact time, initial Ag(I) concentrations, and adsorbent dosage. The adsorption process was found to be most efficient at pH 6. When we tested the most commonly used, Langmuir and Freundlich isotherm models, in the adsorption process in this study, both isotherm models fitted well. The monolayer adsorption capacity of poly(EGDM-methacrylic acid-25 g zeolite) (PMAZ25) and poly(EGDM-methacrylic acid-50 g zeolite) (PMAZ50) was found as 0.116 mg/g and 0.139 mg/g respectively. The adsorption data were also used for the Dubinin-Radushkevich (D-R) isotherm model, and the adsorption energies obtained from this model (EPMZA25 = 15.384 kJ/mol, EPMZA50 = 14.72 kJ/mol) indicated that the adsorption of Ag(I) on polymeric composites could be of ion exchange type. The time dependency experiments indicated that the adsorption rate of Ag(I) onto the polymeric composites was quite fast in the first 60 min and reached adsorption equilibrium after 100 min. Some kinetic models such as the Elovich, pseudo-first-order, and pseudo-second-order models were examined to deeply understand the adsorption kinetics. The kinetic data can be well fitted to the pseudo-second order kinetics model.

Biography

Artical Title: Heatsinks behave as an antenna a source of EMI problems

Abstract

The active/passive heatsinks have recently garnered much attention due to their benefit to keep the temperature of the electronic device and PCB/ICs in a certain range. A heatsink is expected both to perform a maximum cooling thermally and to have a minimum of the radiation in electromagnetic terms since it causes electromagnetic interference (EMI) in devices around. In this talk, many studies discussing the EMI and thermal performance (TP) of that in the literature are going to be discussed. We will look the natural convection heatsinks for thermal and electromagnetic (EM) performances in details. Especially in devices operating at high frequencies, these structures behave like antennas if their electrical dimensions are comparable to the interval of λ - λ/20 wavelengths. Analysis show that the heatsinks act as both a monopole antenna and a patch antenna. To eliminate the EMI from a heatsink, the grounding, shielding, and filtering techniques are studied. In the literature, the grounding methods are studied up to 2GHz and it is determined that it provides improvement up to 12dB. For 1-40 GHz it is possible to have up to 20dB improvements in EMI by using absorbers and shielding methods. The proposed solution approaches in the literature and their results are compared and the advantages and disadvantages of each approach are discussed. The base height of the heat sink is pre-dominant both from the heat dissipation and electromagnetic emission point of view in comparison to other parameters. Both the feeding point and type of feeding can be destructive or restorative for heat sinks from the antenna behavior point of view as well as its dimensions. In conclusion, heat sink performance in terms of temperature cannot be the only point to be taken into account, but their quasi-antenna behavior should also be taken into account.

Biography

Artical Title: Towards micro-mechanic improved design of granular composites

Abstract

In composites, macro properties depend on micro-level morphology such as grains and matrix. Advances in 3D printing, combined with strain measurements by Digital-Image-Correlation (DIC) systems, offer manufacturing “tailor-made” morphologies and measuring the strain fields of entire regions. Analytical tools have been developed, such as Functional-Perturbation-Method (FPM) to account for micro-morphologies and their effect on the macro-level properties. For strength predictions, one can use the FPM and Green’s Functions (GF) to obtain deformation fields as a functional of the heterogenous moduli. Specifically, the heterogeneous strain fields can be approximated using FPM by developing the displacement fields as a Fréchet series about the average homogenous modulus: (0.1) 2D eroded Voronoi morphologies were 3D printed as specimens using PolyJetTM technology. The heterogenous moduli field of each specimen was processed into FPM performed with a GF for the case of a uniaxial tensile load. The 2D generalization of [3] for the first two terms of the Fréchet series for the displacements in yields: (0.2) Experiments revealed that local material morphology has significant impact on marco-level strength. The strain fields calculated by the FPM and GF were compared to ones obtained from DIC in the uniaxial tension tests, as seen in [Fig.1]. “Hotspots” locations were found to be identical to the ones observed experimentally with one of them being the actual fracture initiation location.

Biography

Artical Title: Hot Ecap implementation in zirconia reinforced aluminium chip matrix (Al6061) composite production

Abstract

The demand of aluminium in transportation sector is growing rapidly due to the high strength to weight ratio requirement for fuel saving and performance purpose. There is a need to develop a sustainable recycling process without melting phase for the secondary aluminium production that can further save energy, reduce greenhouse gas emission level and global warming. Therefore, the aim of this research is to perform a meltless equal channel angular pressing (ECAP) method was introduced to process the aluminium wastes in the form of chips in order to achieve the aforementioned agenda. In this study, the composites made of aluminium AA6061 chips reinforced with 5%, 10%, and 15% volume fraction of ZrO2 powder were produced under different processing temperature of 450°C, 500°C and 550°C. The experimental results were analysed using the design and analysis of experiments (DOE) principle, and assisted by the Minitab 18 software. It was reported that the maximum yield strength and hardness increased to 119.26 MPa and 65.25 VH compared to 100.26 MPa and 50 VH (as-received AA6061), respectively.

Biography

Artical Title: Quasispheroidal LiNi0.5Mn1.5O4 coated with Y2O3 and distributed over graphene nanosheets enabling high-voltage and high-energy as cathode in lithium-ion batteries

Abstract

LiNi0.5Mn1.5O4 is a promising cathode material for lithium-ion batteries with a high-voltage spinel structure. A microwave-assisted chemical co-precipitation method was used to synthesize Y2O3 coated quasi-spheres of LiNi0.5Mn1.5O4. The coating of Y2O3 and subsequent wrapping of quasi-spheres in graphene nanosheets does not alter the volume or promote the formation of unwanted phases. TGA analysis shows high thermal stability in the material. The material has an initial capacity of 133 mAh g−1 at C/10 with a retention of 98% after 100 cycles. In addition, cathode samples show a good capacity of 132 g−1 after 20 cycles at higher temperatures (55°C). Oxide coatings protect the particles from ionic leaching but limit the electrical conductivity of the materials. However, graphene enhances the conductivity of the synthesized material and wraps active particles in a conductive channel. Due to the synergistic design of the material and the robust manufacturing technique, parasitic reactions are suppressed without affecting the electrical conductivity. To increase their cyclic performance, the suggested material synthesis approach may successfully be applied to various electrode materials.

Biography

Artical Title: Polyolefin coatings reinforced with modified hybrid CeO2@ZnO particles for corrosion protection of steel

Abstract

This work reported the corrosion protection efficiency of polyolefin coatings, reinforced with modified hybrid cerium oxide and zinc oxide (CeO2@ZnO) particles. The hybrid particles were modified with benzotriazole (corrosion inhibitor). The modified hybrid particles (CeO2@ZnO/BTA) were reinforced into polyolefin-based coatings. The structural and morphological analysis results were confirmed by employing various characterization techniques. Transmission electron microscopic (TEM) analysis confirmed the hexagonal morphology of zinc oxide particle and confirmed the formation of hybrid particles. Energy dispersive X-ray (EDX) analysis results further validated the successful synthesis of the modified hybrid particles. Fourier-transform infrared spectroscopy (FTIR) analysis demonstrated the chemical bonding and interaction of the synthesized particles and endorsed the synthesis due to emergence of unique peaks relevant to particles. X-ray photoelectron spectroscopy (XPS) provided the more in-depth analysis of synthesized particles. Thermal gravimetric analysis (TGA) demonstrated the thermal stability of the modified hybrid particles. UV-vis spectroscopic analysis confirmed the self-release of the corrosion inhibitor (BTA) at various pH values and established the fact that the release is pH and time dependent. Electrochemical Impedance spectroscopic analysis (EIS) represented that the coatings reinforced with modified hybrid particles provided better corrosion protection as compared to the reference blank polyolefin coatings, thus making them an attraction for oil and gas and marine applications.

Biography

Artical Title: Square planar Ni(II), Pd(II), and Pt(II) complexes with new Schiff base ligand (E)-N-cyclohexyl-2-(2-hydroxy-5-methoxy-3-nitrobenzylidene)hydrazine-1-carbothioamide and solvent DMSO: Synthesis, Characterization, X-ray diffraction and anticancer activity

Abstract

The ligand H2L (E)-N-cyclohexyl-2-(2-hydroxy-5-methoxy-3-nitrobenzylidene) hydrazine-1-carbothioamide has been synthesized by the reaction between 2-hydroxy-5-methoxy-3-nitrobenzaldehyde and N-cyclohexylhydrazinecarbothioamide. This ligand was coordinated to metal ion Pd(II) and Pt(II) in basic medium in a mixture of DMSO and methanol solvent. The square planar complexes [PdL.dmso] and [PtL.dmso] were formed via N-S-O coordinating sites of ligand and the fourth coordination bond was formed via S of DMSO which was used as a solvent. The square planar Na [NiL.OAc] complex was formed methanol solvent, whereas CH3COO- occupied the fourth coordinating site. The FTIR, UV-Vis, and 1H and 13C NMR spectroscopy methods were used to characterize the synthesized compounds. The CHN elemental analysis was carried out to determine molecular formula. The two complexes structure of palladium [PdL.dmso] and platinum [PtL.dmso] were completely elucidated with single crystal X-ray diffraction analysis. The cytotoxicity of the synthesized compounds L, a, b and c were tested against cancer cell lines, Hela and human normal endothelial cell lines (Eahy926) by MTT assay. The palladium complex [PdL.dmso] showed the highest activity among all the compounds with IC50 = 15.6 µM against Hela. The nickel and platinum complexes a and c showed significant activity against Hela with IC50 = 105.7 µM and IC50 = 166 µM respectively. The ligand showed very poor activity against Hela cell lines. The nickel complex showed the highest cytotoxicity with IC50 = 5.8 µM and the complexes a, b and ligand, L exhibited the activity with IC50 = 43.3 µM, IC50 = 45 µM, and IC50 = 185 µM respectively against Eahy926. The palladium complex b showed potential activity with a very good selectivity index (SI=2.8) against Hela cell lines. The coordinated complexes showed higher activity than free ligand due to metalation increased lipophilicity. The group 10 metal complexes could be the promising cancer therapeutic agents.

Biography

Artical Title: Synthesis of poly(vinyl alcohol)-aided ZnO or Mn2O3 nanocomposites for acid orange 8 dye degradation: Mechanism and antibacterial activity

Abstract

Zinc oxide is one of the novel metal oxides utilized for diverse applications. The sol−gel and unintended self-propagation procedures were applied to synthesize the porous and high surface area ZnO-based metal oxide nanocomposite. The p-type manganese (III) oxide was successfully coupled with n-type ZnO. The physical property characterization results revealed the surface area, porosity, and charge transfer capability improvement on the poly (vinyl alcohol) (PVA)-aided binary nanocomposite (PVA-ZnO/Mn2O3), compared to ZnO. The XRD patterns and TEM image analysis validated the nanometer size range for the materials (15−60 nm). The SEM micrographs and BET spectral details have confirmed the porous nature of the PVA-ZnO/Mn2O3 nanocomposite. The supporting results were obtained from the HRTEM (IFFT) and SAED pattern analyses. The EDX and HRTEM analyses were used for the confirmation of elemental composition and reality of the PVA-ZnO/Mn2O3 composite, respectively. The presence of the improved charge transfer property for PVA-ZnO/Mn2O3, compared to ZnO, was evidenced from acid orange-8 dye degradation. The highest zone of inhibition (14 mm) was recorded on Escherichia coli bacteria for the uncalcined PVA-ZnO/Mn2O3 nanocomposite compared to PVA, yet, less zone of inhibition compared to the calcined PVA-ZnO/Mn2O3 nanocomposite. The authors recommend the formation of the couple between metal oxides by electrochemical technique analyses as a future work.

Biography

Artical Title: Catechol bio-based polymers for surface modification of nanomaterials

Abstract

Catechol-based polymers have been received much focus as a result of their unprecedented under-water adhesion. Despite of several attempts, the preparation of catechol based materials requires multi-step protection and deprotection of catechol group. The synthesis poly(N-carboxyanhydrides) containing robust anchoring group requires further investigation owing to their structural versatility and potential applications in medicine. The application of organocatalysis in ring-opening polymerization (ROP) of N-substituted N-carboxyanhydride (NCA) monomers is discussed. Important updates on the dual functionality of Brønsted base to subdue the catecholic functions in dormant form and to promote the ring-opening polymerization (ROP) in a living manner is articulated. Well-defined polypeptoids with predicted molecular weights (Mn, NMR = 4.4 KDa) and dispersities (Đ) of 1.1 are synthesized and further used for the functionalization of manganese oxide and silver nanoparticles. Herein, the synthesis of catechol based polypeptoids and polyethers for surface modification of metallic nanoparticles are highlighted. In this review the recent advances in the synthesis of catechol bearing bio-based polymers and organocatalysis in ROP of N-carboxyanhydrides are elaborated in depth. Furthermore, the application of catechol based amphiphilic block copolymers for surface modification of nanomaterials is discussed. This finding could be used as a platform for the synthesis of biocompatible and water dispersible metallic nanomaterials in nanomedicine.

Biography

Artical Title: Nutritional composition and sensory quality of injera prepared from tef (Eragrostis tef (Zucc.) Trotter) complemented with lupine (Lupinus spp.)

Abstract

There is currently an emerging problem of protein malnutrition in Ethiopia. This food formulation was done to increase the accessibility of nutrient rich food products for the consumers. This study aimed to investigate the effect of tef, lupine varieties and blending ratio on the chemical composition of injera and sensory acceptability of Ethiopians staple food. The effect of blending ratio and lupine varieties (Australian sweet lupine and Dibettered lupine seed) were studied. The formulations were generated by using mixture design software. Lupine variety and blending proportion had significant (P < 0.05) effect on proximate, mineral, anti-nutritional compositions and sensory acceptability of blended injera. The nutritional compositions of formulated injera ranged from 60.37 to 66.97%, 1.76 to 2.05 %, 11.78 to 18.84 %, 2.53 to 4.01 %, 2.83 to 3.16%, 72.55 to 81.32% and 393.19 to 400.91 kcal/ 100 g for moisture content, total ash, crude protein, crude fat, crude fiber, utilizable carbohydrate and gross energy, respectively. The result showed that the crude protein content highly increased as the proportion of lupines increased. Crude protein and crude fat contents were higher for injera blended with dibettered lupine seed variety while crude fiber content was higher for those blended with Australian sweet lupine variety because of the raw material. Mineral content of composite injeras varied from 12.26 to 14.98 mg/100 g, 2.39 to 2.83 mg/100 g, and 145.31 to 163.96 mg/100 g for iron, zinc and calcium contents, respectively. Therefore, this study showed significant increment in protein content of injera and provides insights for use of Lupine-tef flour mixture at home and industry level for enriched injera. As the sensory acceptability scores data indicated for both lupine varieties blended with tef for the production of injeras of up to 15% lupines almost all sensory attributes showed higher scores without significantly different among them but after 15% lupine addition there were observed drop of the sensory acceptability scores in a 7 point hedonic scale.

Biography

Artical Title: Investigation of mechanical properties of hybrid natural composite

Abstract

Majority of the conventional materials have been replaced by Natural fiber composites due to their high strength to weight ratio, biodegradable, eco-friendly environment. Based on various literature surveys, natural fibers are a very good alternative for the Engineering and Manufacturing industries. The main goal of this work is to investigate the effect of fiber orientation and wt.% composition on mechanical properties. Fabrication of the composite was made from a hybrid polymer matrix reinforced with nettle fiber (NF), sisal fiber (SF), and glass fiber (GF). Different compositions wt.% of nettle and sisal fiber were used with 00/900 and 450 orientations. A 5% NaOH was used for both fibers to remove further lignin, hemicellulose, and other fiber remnants. The total volume fraction of the fiber was 40 wt.%. From this wt.% of nettle and sisal fibers were hybridized as 20NF:10SF, 15NF:15SF, and 10NF:20SF through 00/900 orientation by keeping wt.% glass constant. The mechanical property results for those samples were very good. In this case, the tensile load and impact force was applied in the direction of both fibers sample S5 and S5’. In the case of S5, the load was applied longitudinally to SF. Whereas in S5’ the load was applied longitudinally to NF. Tensile and impact strength of S5 and S5’ were 97MPa, 8.4J, and 91MPa, 6.9 J respectively.

Biography

Artical Title: The effects of pore size and percentage composition of air voids on impact energy absorption of Al foam using numerical approach

Abstract

Recently, there is a high interest to use lightweight aluminum foams for automotive, railway and aerospace applications. Because of its high ductility and deformability, Aluminum foam is usually used for energy absorption purpose for crashworthiness application. To keep the safety and to avoid occupant injuries it is necessary to absorb the kinetic energy generated during impact. Therefore, to absorb high kinetic energy, the crash box material needs a special material microstructure, which is light in weight and can absorb more energy than the existing one like CaCo3, CBC, SiC. B4C etc. In particular, the analysis of energy absorption of aluminum foam in automotive for energy absorption applications is limited. The main objective of this research is to analyze, and optimize the porosity size and voids percentage on impact energy absorption of aluminum foam using a numerical approach. For this purpose, first, fifteen CAD Al foam specimens were developed by using Digimat multi-scale material modeling software. Second, cubic elements with circular bubble shape at 5%, 10% and 15% void percentage and at 1.5mm, 2mm, 2.5mm, 3mm and 3.5mm bubble sizes were modeled. Finally, the numerical analysis of impact energy by using ANSYS workbench 19.2 Explicit dynamics by applying initial low velocity was performed. The parameters were compared to each other to optimize the proper percentage composition and cell size for the best of energy absorption applications. The effects of bubble shape, foaming agent and percentage composition on energy absorption were discussed. In this study the analysis was accomplished by determining and comparing the energy absorptions of all the models and finally, comparing with existing foaming agents.

Biography

Artical Title: Differential pulse voltammetric determination of hexavalent chromium using nickel hexacyanoferrate modified glassy carbon electrode

Abstract

The current boom in the industrial sector of the country is arise scientific concern about environmental contamination by heavy metals such as chromium. The objective of this project is to fabricate a sensitive and selective electrode for differential pulse voltammetric determination of Cr (VI) in water samples and demonstrate its applicability in complex matrices such as tannery effluent. The drop casting method is use for electrode development. Experimental variables that can influence the DPV response of the developed electrode for Cr (VI) including strength of supporting electrolytes, pH of the solution, and concentration parameters were optimized. The figures of merit of the developed electrode were evaluated and the applicability was demonstrated through determination of Cr (VI) in tannery effluent water. The developed electrode was detected a very low level of Cr (VI) in acetate buffer at pH 5 with limit of detection and limit of quantification 0.0885 and 0.2950 μmol L-1 respectively. The linear calibration plot is R2 value of 0.999 suggesting a very good correlation between DPV current response and concentration of Cr (VI). The current electrode was simple to develop and can successfully be applied for the determination of Cr (VI) in wastewater samples.

Biography

Artical Title: Preparation of skin care product using coccinia abyssinica tuber extract

Abstract

Background: Anchote (Coccinia abyssinica) is highly nutritious crop which is mostly cultivated in Wollega Zone, Oromia Regional State of Ethiopia. The term ‘anchote’ is the local name of coccinia abyssinica. Anchote is traditional food crop which play a pivotal role in nutritional security, especially in the western Oromia Regional state of Ethiopia. It is herbaceous plant species which is usually consumed in cooked form. Tuberous root is the main edible portion of coccinia abyssinica. A number of essential nutrients in anchote such as Calcium, Starch, Zinc, Magnesium, Iron, protein and etc makes it the most important food crop. Materials and Methods: Coccinia abyssinica tuber extract was prepared by maceration extraction method. Coarsely powdered coccinia abyssinica tuber was placed inside a container; menstruum was poured on top until completely covered the powdered tuber. The container was then closed and kept for three consecutive days. The content was stirred periodically to ensure complete extraction. At the end of extraction, the micelle was separated from marc by filtration. Then, tuber extract of coccinia abyssinica was mixed with ingredients such as thickening agents, humectant, emollient, antioxidant, preservatives and fragrance to prepare a new skin cream. A new skin cream was formulated by mixing ingredients. Results: Whitish brown semi-solid cream was prepared by mixing ingredients. A newly prepared skin care product was applied to the human skin. The skin became soft, attractive and supple after using this new skin care product. It didn’t cause any side effects on the human body. Conclusions: Calcium, starch and other nutrients in anchote tubers are vital for our skin. Thus, a new skin care product was prepared using tuber extract of coccinia abyssinica (anchote) with the aim of nourishing the skin. The current study revealed that coccinia abyssinica skin care product enrich the body with nutrients and useful minerals. Coccinia abyssinica skin cream offers significant advantages over competing products.

Biography

Artical Title: Techno-economic analysis for Li-ion battery recycling in the UAE

Abstract

Nowadays, millions around the world rely on portable electronics and electric cars to get around. Numerous modern gadgets are powered primarily by rechargeable lithium-ion batteries. The current study will examine the environmental and economic benefits of recycling lithium-ion batteries at the end of their useful lives. Lithium (Li), Cobalt (Co), and Manganese are the three most precious metals utilized in these batteries. This study is considered as the first comprehensive study and database dedicated to the United Arab Emirates hydrometallurgical recycling technique which was generated utilizing the Argonne National Laboratory's EverBatt cost model. It has been investigated the differences in costs between the various LIBs chemistries. We demonstrate a comparison between the recycling price of the LIBs in the United Arab Emirates and the recycling price of the same battery material in the United States. A number of different battery chemistries have been employed, including NMC (111), NCA, and LCO. The purpose of this study is to quantify the environmental impacts and costs associated with remanufacturing NMC111, NCA, and LCO battery cells and to compare them to the costs associated with manufacturing batteries from virgin materials in order to determine whether battery remanufacturing is feasible. The model is using the cost calculation from BatPaC as well as the environmental impact calculation from GREET to make its decisions. The amount of energy consumed, the amount of trash generated, and the recycling efficiency all have a significant influence on the environmental advantages and economic sustainability of LIB recycling. As a result, EverBatt model was utilized to analyze the particular LIB disassembly procedure in terms of these factors. We will compare the pricing of recycling LIBs at recycling facilities in the United Arab Emirates and the United States. We will examine different recycling process with different recycling fractions ranging from 80% to 100%, as well as varied annual throughput volumes of 8,000, 10,000, and 12,000 tonnes, respectively. Additionally, many prices or different recycling techniques are compared, including pyrometallurgy and hydrometallurgy.

Biography

Artical Title: Relationship between silicon, phosphorus content and grain number in mild steels and its corrosion resistance in pickling hydrochloric acid

Abstract

The micro-structural effects on the corrosion resistance of three classes of mild steels (A, B and C) suitable for galvanizing industry, according to their silicon, phosphorus content, grain number and size of carbides (Fe3C) in concentrated hydrochloride acid solution was investigated by a series of known techniques, such as potentiodynamic polarization curves, electrochemical impedance spectroscopy measurements, optical microscope and scanning electron microscopy. Results showed that the corrosion rate of the three classes of mild steel depends on their silicon and silicon/phosphorus combinations contents. It is found also that the corrosion rate depends on grain number and size of carbide content in mild steels. These findings were confirmed by micro-structural characterization and scanning electron microscopy techniques. They indicated that the severe corrosion cavities formed on the carbon steel surfaces and their sizes depended to silicon and silicon/phosphorus combinations contents. These results explained by micro-galvanic corrosion process between cementites and ferrites which became more serious with silicon and silicon/phosphorus combinations contents.

Biography

Artical Title: Characterization of Na0.5Bi0.5TiO3 prepared by hydrothermal method for photocatalytic applications

Abstract

Sodium bismuth titanate (Na0.5Bi0.5TiO3, NBT) ceramics have been prepared by using a simple hydrothermal method. Low temperature process of thermal treatment was conducted to obtain a highly dense morphology NBT, using high-purity oxides and carbonates as the initial precursors. The presence of well-crystallized NBT in the rhombohedral phase was also found at hydrothermal temperatures above 180°C. A concentration of at least 10 M NaOH and a reaction time of at least 24 hours were needed to attain maximum perovskite phase. Xray diffraction, Raman spectroscopy, Infrared spectroscopy, and SEM analysis confirm the structure, phase, morphology, and composition. NBT ceramics exhibit the typical characteristics of relaxor ferroelectrics, with a diffusion exponent γ of up to 1.5 to promote their applications in micro-electromechanical and energy harvesting systems. The photocatalytic properties of the hydroth- ermally synthesised powder were evaluated with respect to the degradation of meth- ylene blue (BM). Furthermore, the photocatalyst's stability is excellent. The article carefully discusses the detailed mechanism of photocatalysis.

Biography

Artical Title: Effects of high operating temperatures and holding times on thermomechanical and mechanical properties of autoclaved epoxy or carbon composite laminates

Abstract

The elevated operating temperature is considered an essential factor affecting the performance of laminated composite structures. Under the intended conditions of use in aircraft engines and nacelles, carbon fiber reinforced polymers are exposed to temperatures ranging from room temperature to 120°C. The present work concentrates on the thermomechanical and mechanical properties of autoclaved woven carbon fiber/epoxy composite laminate subjected to different operating temperatures (60, 120, and 180°C) and holding times (10, 30, and 60 min). Thermomechanical results showed that the rigidity and stiffness of the epoxy resin matrix decrease with increasing temperature. However, all mechanical properties (laminate compressive modulus, laminate compressive strength, and interlaminar shear strength) decreased progressively with operating temperature. Laminate compressive strength and interlaminar shear strength were seen to decline up to 43.74% and 30.60% on the operating temperature of 180°C, respectively, compared to measured values at 60°C. This study indicates that only the compression properties were affected by the holding time, while the interaction between the operating temperature and holding time affects the laminate compressive modulus.

Biography

Artical Title: Boundary stabilization of a thermoelastic diffusion system of type II

Abstract

In this paper we study the boundary stabilization of a one-dimensional thermoelastic diffusion problem of type II. The system of equations is a coupling of three hyperbolic equations. This poses some new mathematical and numerical difficulties. With the help of the semi group theory of linear operators, we prove the well-posedness of the proposed problem. By using the frequency domain method combined with the multiplier technique, we prove the exponential stability of the solutions. Finally, we present a numerical scheme based on the Chebyshev spectral method and we give two numerical examples to validate the proposed model and to show its capability.

Biography

Artical Title: The geometric free-surface profile of granular flows in rotating drums

Abstract

The axial and free surfaces are geometric features of tumbling mill flows. Their shape is a characteristic of the particle interactions within the charge body. This means that any modelling scheme capable of predicting these surfaces automatically satisfies the underlying physics of the system and thus can be used as a global continuum signature for breakage and mixing. Elbasher et al (2021) presented a model that successfully captured the shape of the axial free surface by comparing their results to axial free surface predictions from Chou et al (2009). Due to the encouraging results from that work, we leverage off the geometric symmetry between the axial free surface and sigmoid-shaped (S- shaped) free surfaces and present an analytical solution, free from any empirical fitting parameters, to predict S-shaped free surface. These predictions are then statistically compared to those derived from previously conducted Discrete Element Method (DEM) simulations and positron Emission Particle Tracking (PEPT) experiments. This model provides an alternate to complicated numerical routines that fit S-shaped free surfaces to experimental data; these are often prone to regions of numerical instability depending on the nature of the data-set.

Biography

Artical Title: Recent advances in microneedle platforms for transdermal drug delivery technologies

Abstract

In many clinical applications, the transdermal route is used as an alternative approach to avoid significant limitations associated with oral drug delivery. There is a long history for drug delivery through the skin utilizing transdermal microneedle arrays. Microneedles are reported to be highly efficient and versatile devices. This technique has attracted scientific and industrial interests, due to its outstanding characteristics such as painless penetration, excellent medicinal efficiency, relative protection and affordability. The microneedles have shown considerable potential to create advanced functional devices with remarkable properties for biomedical applications such as delivery of very large substances with ionic and hydrophilic physicochemical properties. In this review we present a summary of recent advances in microneedles-based drug delivery, typical materials used for their construction and fabrication methods that improves the delivery of critical substances through the protective membranes. Further, it explores the practicality of innovative microneedles used as a drug delivery tool. Microneedles are emerging tools that have shown profound potential for biomedical applications. Transdermal microneedle technologies are likely to become a preferred route of therapeutic substances administration in the future since they are effective, painless, and affordable.

Biography

Artical Title: A review on polyimide reinforced nanocomposites for mechanical, thermal, and electrical insulation applications: Challenges and recommendations

Abstract

In this paper, the application of polymer composites as a candidate material for thermal and electrical insulation was firstly introduced. Polyimide nanocomposites have drawn much attention as mechanical, thermal, and electrical insulation materials because of its superior dielectric, thermal, and corona resistance behaviours. Thus, polyimide nanocomposites are described as substance of polyimide matrix reinforced with certain weight percent content of nanofillers. Several researches have demonstrated the utilization of polyimide nanocomposites in mechanical, thermal, and electrical applications. However, the nanocomposites are noted facing interfacial bonding issues, which have affected their mechanical performance for thermal and electrical insulation behaviours. The dielectric properties and corona resistance lifetime of the polyimide nanocomposites are reportedly deteriorated over a long term exposure to high temperature condition. There has been advancement on improving the mechanical, thermal and electrical characteristics of polyimide nanocomposites for multifunctional insulations. Hence, this paper summaries the influence of nanofillers, such as alumina (Al2O3), silica (SiO2), titanium dioxide (TiO2), graphene (GN), nanotubes (NTs), boron nitride (BN), and some other fillers on the mechanical, thermal, and electrical properties of polyimide nanocomposites for insulation applications. As the study offers great insight into the improvement and selection of polyimide nanocomposites material for mechanical, thermal, and electrical insulation, the authors concluded the study with advancement, challenges and recommendations for future improvement of polyimide nanocomposites as an insulation material.

Biography

Artical Title: Surface dependent properties and tunable photodetection of CsPbBr3 microcrystals

Abstract

All-inorganic metal halide perovskites are highly attractive materials for optoelectronics and are typically implemented as thin films, nanocrystals, and single crystals with macroscopic and millimeter-size dimensions. Here, CsPbBr3 microcrystals are fabricated by simple and fast drop-casting of a precursor solution on several substrates that for the growth process are heated to temperatures in the range from 80 to 150°C. The microcrystals have a cubic shape and feature a pyramidal cavity on their top surface that forms due to faster growth at the edges once the growing crystal is attached to the substrate. Distinct heterogeneity in the photoluminescence (PL) and conductivity of the different facets are measured by µ-PL and conductive atomic force microscopy experiments. Toward device applications, the authors contact single microcrystals on conductive substrates mechanically with a micromanipulator tip. They observe diode-like current–voltage curves and good photodetector functionality, obtaining a high responsivity of 150–300 AW−1 in the blue–green spectral region under forward bias, and a sharp detection band centered around 540 nm with peak responsivity close to 0.7 A W−1 under reverse bias.

Biography

Artical Title: Association of some dietary ingredients, vitamin D, estrogen, and obesity polymorphic receptor genes with bone mineral density in a sample of obese Egyptian women

Abstract

Although many environmental factors play an important role in bone mass density (BMD) variation, genetic influences account for 60–85% of individual variance. The aim of this study was to find the interaction between some dietary ingredients, vitamin D, estrogen, and obesity polymorphic receptor genes, among a sample of obese Egyptian women. This was a cross sectional study included 97 women (aged 25–60 years). Data on anthropometry, dietary intake, BMD, biochemical, and genetic analyses were collected. Results: Osteoporosis was high among women had dominant Taq1 vitamin D receptor gene while osteoporosis was less common among the homozygous Apa1 receptor gene women. Both genes in their two forms did not show any effect on serum vitamin D. Heterozygous types of osteoporotic women carried both genes revealed a slight but significant decrease in level of serum calcium. Xba1 estrogen receptor gene was identified only in a homozygous type while the heterozygous Pvu11 estrogen receptors gene has been identified among both osteoporotic and non-osteoporotic women, this gene was associated with higher BMI in both groups compared to the homozygous receptor gene. Mutant types of genotype FTOrs99 and FTOrs80 obesity receptors genes were less common (4.44%, 11%) among participants. Both of these genes were associated with the highest value of BMI and caloric daily intake, fat, and saturated fatty acid that were more prominent among osteoporotic women. Conclusion: There is significant association between vitamin D, estrogen, obesity receptors genes, special nutrients, and osteoporosis. Increased BMI, calories, and fat intake lead to rise of genetic predisposition and susceptibility to osteoporosis.

Biography

Artical Title: Dosimetric impact of some gamma radiation-induced polymeric materials incorporated silicate using thermoluminescence and ultrasonic techniques

Abstract

Polyacrylamide acrylonitrile magnesium silicate {P (Am-AN)-MgSi} & polyacrylamide acrylic acid magnesium silicate {P (Am-AA)-MgSi} hybrid composites were fabricated utilizing gamma-radiation polymerization initiated about 30 kGy. Different types of dosimetric radiation-induced polymeric composites were irradiated by cesium-137 gamma-ray dose to show its possibility for use as a thermoluminescence dosimeter. The prepared polymeric composites showed useful properties such as good dosimetric and thermal stability behaviors. The mechanical behavior of the samples was measured non-destructively by the ultrasonic pulse-echo technique. It was found that the addition of P (Am-AA) with higher elastic moduli to MgSi with lower ones are produced in the {P (Am-AA)-MgSi} composite sample with a midway value for Young’s modulus of 7.13 GPa and shear modulus of 2.71 GPa. Dissimilar in the {P (Am-AN ).

Biography

Artical Title: New improved thermoluminescence magnesium silicate material for clinical dosimetry

Abstract

Magnesium silicate has been prepared by a precipitation technique. This composite structure was proven by different tools, XRD, TGA&DTA, FTIR, and XRF. Magnesium silicate was found to have the formulas Mg1.1SiO3.2.1.1H2O. Thermoluminescence (TL) dosimetric properties like (linearity, fading, energy independence) of magnesium silicate in the shape of MgSiO3 have been estimated. A strong TL dosimetry peak associated with gamma radiation arises from 137Cs was developed. Different doses from gamma radiation were measured by thermoluminescence (TL) detection technique for magnesium silicate glasses in unique magnesium elements concentration to assess its dosimetric properties. A single strong peak of about 230°C arises for all irradiated samples. Total integral values of TL output and TL of the principal peak values showing a linear behavior start with 0.5 Gray up to 2 Gray dose range. Correlation of magnesium silicate TL response and different doses showed dose-response improvement concerning low doses linear relationship.

Biography

Artical Title: Modified austenitic stainless-steel alloys for shielding nuclear reactors

Abstract

In nuclear fields steel alloys are generally used for radiation shielding especially in structure of nuclear reactors. The cobalt element is one of the steel alloys composite elements. The cobalt element is an expensive element; this makes the steels rather expensive, preventing wider selection and application. So the principal aim of this research is preparing cobalt-free stainless steel as shielding to reduce the production cost. Therefore, seven different free-cobalt steel alloys were prepared by using an electro slag re-melting technique. Steel compound ratios were determined by using XRF techniques and the attenuation properties of these alloys were studied by using the software WinXCOM computer program at photon energies 80, 356, 662, 1173, and 1332 keV. Furthermore, the total macroscopic cross-section was determined by using “Geant 4” code for fast neutron radiation shielding. Also the mean free path, half value layer, the atomic effective number and Transmission coefficient of neutron dose calculated. The results prove an excellent cobalt-free steel alloys have good mass attenuation to be used as a proper shielding material in the nuclear field, this clear such as in the sample (0.032 % Ni, 0.009 % Mo, 0.087 % Cr, 0.948 % Mn, 0.002 % Ti, 0.005 % V, 97.01 % Fe, 0.3 % C, 0.035 % P, 0.012 % S) with density 8.28 g/cm3. Also shielding parameter variations were applied to the steel alloys to investigate the superior shielding properties to gamma rays.

Biography

Artical Title: Facile and green synthesis of silver quantum dots immobilized onto a polymeric CTS-PEO blend for the photocatalytic degradation of p-nitrophenol

Abstract

Immobilization of inorganic metal quantum dots (especially, noble transition metals) onto organic polymers to synthesize nanometal−polymer composites (NMPCs) has attracted considerable attention because of their advanced optical, electrical, catalytic/photocatalytic, and biological properties. Herein, novel, highly efficient, stable, and visible light-active NMPC photocatalysts consisting of silver quantum dots (Ag QDs) immobilized onto polymeric chitosan−polyethylene oxide (CTS−PEO) blend sheets have been successfully prepared by an in situ self-assembly facile casting method as a facile and green approach. The CTS−PEO blend polymer acts as a reducing and a stabilizing agent for Ag QDs which does not generate any environmental chemical pollutant. The prepared x wt % Ag QDs/CTS−PEO composites were fully characterized through X-ray diffraction, Fourier transform infrared spectroscopy, transmission electron microscopy (TEM), thermogravimetric analysis, and UV/visible spectroscopy. The characterization results indicated the successful synthesis of the Ag QDs/CTS−PEO composites by the interactions and complexation between x wt % Ag QDs and CTS−PEO blend sheets. TEM images revealed small granules randomly distributed onto the CTS−PEO blend sheets, indicating the immobilization of Ag QDs onto CTS−PEO composites. The presence of a surface plasmon resonance (SPR) band and the shifting of the absorption edge toward higher wavelengths in the UV/vis spectra indicated the formation of x wt % Ag QDs/CTS−PEO composites. The Ag QDs in the polymeric blend matrix led to remarkable enhancement in the optical, thermal, electrical, and photocatalytic properties of x wt % Ag QDs/CTS−PEO composites. The photocatalytic efficiency of the prepared composites was evaluated by the photodegradation of p-nitrophenol (PNP) under simulated sunlight. The maximum photocatalytic degradation reached 91.1% efficiency within 3 h for the 12.0 wt % Ag QDs/CTS−PEO photocatalyst. Generally, the Ag QDs immobilized onto CTS−PEO blend composites significantly enhance the SPR effect and the synergistic effect and reduce the band gap, leading to a high photocatalytic activity.

Biography

Artical Title: Human toxoplasmosis in Mozambique: Gaps in knowledge and research opportunities

Abstract

Toxoplasmosis is a parasitic zoonotic disease caused by the Toxoplasma gondii zoonosis that afflicts humans worldwide and wild and domestic warm-blooded animals. In immunocompetent individuals, the acute phase of infection presents transient low or mild symptoms that remain unnoticed. Although the lifelong persistence of the dormant form of this parasite can lead to different toxoplasmosis clinical forms in immunocompetent individuals and immunocompromised patients and be related to neuropsychiatric disorders and neurodegenerative diseases. In immunocompromised patients, Toxoplasma is a life-threatening opportunistic infection, which can result from the reactivation of latent infection or primary infection. Moreover, congenital toxoplasmosis, which results from the transplacental passage of tachyzoites into the fetus during a pregnant primary infection can lead to miscarriage, stillbirth, or ocular and neurologic disease, and neurocognitive deficits in the newborns. Thus, the present review aims to address the current knowledge of Toxoplasma infection and toxoplasmosis in Africa and especially in Mozambique, stressing the importance of identifying risk factors and promote awareness among the population, assessing the gaps in knowledge and define research priorities. In Mozambique, and in general in Southern African countries, clinical disease and epidemiological data have not yet been entirely addressed in addition to the implications of T. gondii infection in immunocompetent individuals, in pregnant women, and its relation with neuropsychiatric disorders. The main gaps in knowledge in Mozambique include lack of awareness of the disease, lack of diagnostic methods in health facilities, lack of genetic data, and lack of control strategies.

Biography

Artical Title: Features of the process of compaction of powder aluminum alloys by cold pressing

Abstract

A schematic model of the compaction process of spherical particles of different sizes is proposed. In this regard, the process of compaction of granules was considered in the context of three stages. It has been found that in the first stage there is an active compaction, as a result of which the packing of the powder particles becomes tighter. At the second stage, as a result of an increase in the pressing pressure, the contact areas of the particles increase and juvenile friction surfaces are formed, which enhances their molecular interaction and friction resistance. At the transition of pressing from the 2nd stage to the 3rd, the generated pressure strengthens the mechanical contacts and causes the extrusion of particles into the micropores of the pressing. Large differences between pellet sizes improve the extrusion of fine particles. The analysis of changes in some mechanical parameters of a porous composite material based on aluminum, depending on the applied pressure during compaction, is carried out. With the help of special devices based on compression models proposed by different researchers, the change in the relative density of the porous material depending on the pressing pressure was studied. In conventional and semi-logarithmic coordinate systems, graphical descriptions of the dependences of the relative density of briquettes on the pressing pressure, as well as their initial microhardness on the particle size, are given. In addition, curves were presented that characterize the effect of pressing pressure on both the microhardness of briquettes with different fractions and their shear and compressive strength. Calculation formulas are given that make it possible to calculate the areas of initial and current pores, depending on the particle size of the constituent fractions, at any moment of load application until the powder is completely compacted.

Biography

Artical Title: Comparative analysis of photovoltaic - thermal (PVT) and photovoltaic (PV) modules

Abstract

Solar photovoltaic and thermal (PVT) is a hybrid technology that combines photovoltaic (PV) solar cells, which converts solar energy into electricity, with a solar thermal collector, which transfers the unused excess heat from the PV module into the useful thermal energy in the form of heated water or air. The hybrid PVT system proves to be more energy efficient with improved electrical efficiency due to cooling of PV cells and obtained thermal energy due to heat absorbed from heated PV cells. Nevertheless, the utilization of these systems does not grow rapidly due to the controversial operational problems. In this work, the operational problems of PVT technology are investigated. The comparative analysis of properties of PVT modules and general PV module has been conducted. The operating temperatures of solar cells in PV and PVT modules under the dependence of ambient temperature and other parameters theoretically and experimentally have been investigated. On the base of comparison of operating temperatures of solar cells in PV and PVT modules, the efficiency of PVT hybrid module has been analyzed. It is demonstrated that when the ambient temperature is low, the temperature of PVT module can be higher than the temperature of the general PV module, due to the decreased convection cooling of PVT in comparison with the PV module. The ambient temperature, below which the PVT module is hotter than the PV module, is called “critical”. As a result of this process, the electrical efficiency of the PVT module becomes smaller than the efficiency of the PV module. This effect is called the “reverse” process. It has been concluded, that to overcome this operational problem, the PVT system and its functionality must be optimized taking into consideration the weather conditions under which the PVT system will be used.

Biography

Artical Title: Enhancement of photoluminescence properties of nano-sized Pr3+ doped LuPO4 powders by incorporating of Y3+ ions

Abstract

The work explores the enhancement of photoluminescence properties of nano-sized LuPO4:Pr3+ phosphor powders synthesized by sol gel process with incorporation of yttrium ions inside of this single matrix to obtain (Lu1-xYx) PO4:Pr3+ (x=10, 20, 30, 40, and 50 at. %) powders. Under UV excitation at 270 nm the emission spectra of LuPO4:Pr3+ nanopowder do not present any characteristics emission band attributed to 4f15d14f2 transitions of Pr3+ ions, while a large emission band has been observed which due to defects created in LuPO4 cell by doping considering the ionic radius of Pr3+ is larger compared to the ionic radius of Lu3+, this band extinguishes gradually at the time insertion of the Y3+ ions until its total disappearance (for x=40 at. %).It was found that the emission spectra of (Lu1-xYx)PO4:Pr3+ nanopowders under λex=230nm presents only the characteristics emission bands of Pr3+ ions with a remarkable influence of the rate of Y3+ ions on the intensity of this bands. Furthermore, it was observed that the improvement in the luminescence properties of (Lu1-xYx) PO4:Pr3+ nanopowders is very remarkable in visible range.

Biography

Artical Title: New design of quad-band polarisation-insensitive metamaterial absorber based on dual-T shaped resonator array for C-, X- and Ku- bands microwave applications

Abstract

Multi-band metamaterial absorbers (MMAs) are increasingly becoming the main devices for many electrical systems. Optimizing the electromagnetic qualities of this type of absorber in the microwave regime is a relatively complex operation. In this paper, a quad-band Metamaterial Absorbent MMA covering the microwave bands is provided. The proposed MMA for analysis and design is formed by an (16×16) array of metamaterial base cells. Each cell has an interconnected circular T-C shaped split ring resonator (CTC-SRR) etched on the top face of FR4_Epoxy substrate for electrical dimensions (0.18λ_0× 0.18λ_0) where λ_0 is calculated at the lower frequency of 4.6 GHz in the C-band. The electromagnetic qualities of our MMA are expired by the behavior of each basic cell which represents a left hand medium and a negative permeability (μ<0) for magnetic resonances at the frequencies 4.6 GHz, 9.2 GHz, 11.3 GHz and 15.8 GHz. The obtained results simulations performed by the High-Frequency Structure Simulator (HFSS) computer show an insensitive-polarization quad-band behavior for our proposed MMA. The spectral responses of the absorber cover the C-, X- and Ku-bands for important absorption coefficients of the order of 96.22%, 93.25%, 98.46% and 92.37%.

Biography

Artical Title: From metallic to semiconductor conversion of single-walled carbon nanotubes by chlorination

Abstract

In this research, single-walled carbon nanotubes (SWCNTs) were treated with strong HClO4 acid. Then investigated first by UV–vis-NIR absorption, Fourier transform infrared (FTIR) and Raman spectroscopy; and secondly by numerical calculations based DFT using generalized GGA and LDA as implemented in SIESTA code. The results show significant changes in the behavior of metallic nanotubes and DFT calculations (GGA and LDA) show that adsorption of chlorine atoms on the metallic (9,9) carbon nanotubes wall generates an energy gap in the electronic structure of these nanotubes, confirming the experimental results. This highlights a conversion of metallic nanotube to semiconductor.

Biography

Artical Title: Enthalpy behavior of ZnO zinc blende structure under isobaric and isothermal ensembles a MD computation

Abstract

In this work we used Parallal Molecular Dynamics and DL_POLY_4 (calculations ran on RAVEN supercomputer of Cardiff University) to analyze enthalpy behavior of ZnO Zinc Blende structure under different pressures and temperatures. Our system is formed from 5832 atoms of ZnO (2916 atoms of Zn+2 and 2916 atoms of O-2), the interatomic interactions are modeled by Coulomb-Buckingham Potential for short and long-range, the range of temperature is 300-3000K and for pressure is 0-100GPa. Although no more data under previous conditions our results are in the vicinity of available experimental and theoretical information. This work is very important in nanoscale of time and space and in different sectors of industry.

Biography

Artical Title: Phosphido-Bridged Trinuclear Platinum Clusters: A DFT Study

Abstract

The compound H(PEt3)3Pt3(μ-PPh2)3 is the unique example of a 46e− phosphido-bridged triangular cluster, but its X-ray assigned stereochemistry appears questionable. In particular, the H-free P3Pt3(μ-P)3 metal core is identical to that of the 44e− cation [(PEt3)3Pt3(μ-PPh2)3]+ in two salts of the same publication. Also, the lack of a distortional effect due to the upright and strongly-bound hydride ligand is suspicious and intriguing aspects emerge from the inconsistent electronic structure. Although H(PEt3)3Pt3(μ-PPh2)3 is fully validated by IR and NMR spectra, DFT optimizations never reproduced the proposed experimental structure but highlighted a different stereochemistry still consistent with the spectroscopic response. Here, a formal Pt(II) ion is essentially isolated and has square-planar coordination, completed by two trans-axial ligands (H and Et3P) out of the Pt3 plane. Given the chemical reliability of the in silicomolecule, the crystals of the experimental structure have likely contents other than the hydridic cluster and a co-crystallized Ph2PH molecule. As a working hypothesis, the Pt-H and P-H linkages of the distinct components may have reacted together with H2 release, and subsequent cristallization of the salt whereas the ion pair [(PEt3)3Pt3(μ-PPh2)3]+/[Ph2P]−. This would explain the equal geometries of the putative 46e− cluster and the H-free 44e− cation. In the lack of any experimental X-ray dataset, the proposed crystal formulation could not be fully validated, but in the paper various aspects support its reliability.

Biography

Artical Title: Modulational instability and chaotic-like behaviors in repulsive lattices

Abstract

In this work we study the dynamics of modulated waves in a mono atomic granular medium. We start by comparing each grain of the medium to a ball, and the interaction between various balls like linear elastic interactions we established that the dynamics of the system of pendulum used by Fermi-Pasta-Ulam can be governed by a discrete nonlinear Schrödinger equation. Like second advanced, we also established under which conditions this system could be prone to a modulational instability. The long-time dynamics of modulated waves is examined using numerical simulations which are corroborated with analytical results leads to the generation of nonlinear modulated waves which have the shape of a soliton.

Biography

Artical Title: Energy potential assessment and characterization of fuel briquettes made from Cameroonian agricultural crop residues

Abstract

Scope and objectives: For sustainable development purposes, it may be advisable to substitute fuelwood for fuel briquettes in household cooking in countries with high agricultural potential as Cameroon. The objectives of this study are firstly to assess the theoretical energy potential which could be recovered from agricultural residues for fuel briquettes production; prepare and characterize fuel briquettes using banana peels, rattan waste, coconut shells, palm oil shells and sugarcane bagasse; finally analyse the benefits and barriers of briquetting conversion of these residues in Cameroon. Methods: The Residues-to-Product Ratio (RPR) method was used to calculate the energy potential. Fuel briquettes were prepared through a conventional method and evaluated by proximate analysis using American Society for Testing and Materials (ASTM) standard, European Committee for Standardization (CEN) standard and Thermo-Gravimetric Analysis (TGA). Results: The study carried out shows that briquetting conversion of these residues could produce 7 706 260 tons.yr-1 of fuel briquettes, the energy potential value is about 106 PJ.yr-1. Results of mass reduction study show that the losses are more important for banana peels (97.98%) and sugarcane bagasse (96%). Bulk density of briquettes produced is in the range 0.470–0.851 cm3/g; results of proximate analysis show that high calorific values of briquettes produced are 14.25, 16.98, 30.07, 32.16 and 25.93 MJ/kg for palm oil shells, banana peels, rattan waste, coconut shells and sugarcane bagasse respectively; ash content has values in the range 7.44–11.95%, and moisture content is relatively higher than other agricultural residues especially banana peels and sugarcane bagasse. Conclusion: It is concluded that availability of agricultural residues in that country gives an important potential for briquette production from biomass crops resources. It would interest to valorise this potential considering political, logistical and seasonal crop constraints.

Biography

Artical Title: Interplay role between dipole interactions and hydrogen bonding on proton transfer dynamics

Abstract

In our work, we examine the role of dipole-dipole interactions on proton dynamics and properties of defects in hydrogen bonding systems. These interactions created by protons and heavy ions allow us to generalize the original Antonchenko-Davydov-Zolotaryuk model. One of the particularities of our model is the shape of the dipole-dipole interaction, which better expresses and explains real systems compared to the classical harmonic interactions usually used. It emerges that the characteristic parameter of the dipole- dipole interaction  is of capital importance in the study of the coupled differential equation of hydrogen bond systems, at the points where its variation drastically changes the dynamics and qualitatively modifies the solutions of the system. The number of solutions obtained and the study of their behavior at the slightest deviation , imply the use of the theory of bifurcations. This theory allowed us to obtain 23 phase portraits, each trajectory of which determines the possible displacement of the proton. For each orbit of the phase portraits obtained, this under very precise conditions, all possible exact parametric representations of the solutions are identified. It is clear that their interpretation shows a much richer variety of solitons. It appears that  influence differently the proton in function which he has a subsonic, sonic or supersonic speed, but its variation makes it possible to obtain several exact parametric representations of the solutions (periodic solutions, peakon, kink and antikink, compacton, etc.) and singular straight lines. However, due to their robustness, we have chosen the compacton-type solutions having the shape of the kink (Kinkon) to determine the dynamic quantities of the system such as the energy and momentum of the kink (k) and the anti-kink (ak), physical quantities such as mobility and conductivity, in order to better appreciate the validity of the model and the theories we have proposed.

Biography

Artical Title: Material, waste, energy and environment

Abstract

Material science is the study of material; while material is everything outside nothing i.e. material science is the study of everything outside nothing. Every tangible thing in the universe is a material. Materials are used every day by human for living. Materials can be useful or waste. Over the years, materials are being transformed using technology available at the material time to make living more comfortable; but as technology continue to advance, materials made with old technology are been abandoned generating waste. Also when an equipment fails or stops to perform it primary function, it’s been abandoned or dumped. This action over the years keep increasing the amount of waste in our environment. As we keep using and developing materials, we keep abandoning old materials causing waste to increase. In most part of the world, waste is beyond control causing environmental hazard. Ojelola K. et al (2020) studied the waste generation and it management in the most populous city in Africa (Lagos, Nigeria) with the objective of transforming waste in useful products. With aim of transforming waste, Taiwo Alare et al. (2020) presented a model of smart waste cycle which included bioenergy generation, refining and recycling. A lot has been done by researchers on waste transformation especially in the area of biofuel and wastewater purification. It is difficult to know amount of solid waste available in geographical location and in order to reduce via transformation the amount of available waste should be known to ensure efficient operations. In other to increase the exactness of waste data, Taiwo Alare and Kehinde Alare (2021) developed a mathematical formula to calculate amount of solid waste in a location. As material is a necessary tool in production, in order to reduced cost of production Olanrewaju Akinnawo and Taiwo Alare (2021) used waste in production of a paper cutting machine which tend to reduce the cost by 80%. As material scientists, it is high time we stopped wasting waste.

Biography

Artical Title: Prediction of the reflection intensity of natural hydroxyapatite using generalized linear model and ensemble learning methods

Abstract

Laboratory data acquisition and analysis of X-ray diffraction (XRD) data involves a lot of tedious human engineering and is time-consuming. To put in context, a summation of the material synthesis procedure leading to the analysis of the structure of the material can span several days. To curb this challenge and to enhance innovations in engineering pedagogy, this article investigates an alternative method that uses supervised learning algorithms based on ensemble techniques and a generalized linear model (GLM) for predicting reflection intensity (XRD patterns) of raw and natural hydroxyapatite under varying sintering temperature conditions given Bragg angles as input to the machine learning algorithms. For the experiment, we trained GLM and ensemble learning models (CatBoost, LightGBM, and two variants of XGBoost based on manual and genetic algorithm for tuning of the hyperparameters). The results show that most instances of the XGBoost yielded a robust performance that surpasses all other approaches, when predicting X-ray reflection intensities ascribed to the biomaterials subjected to varying sintering temperature conditions. In addition, the results show that all the ensemble techniques significantly outperform the GLM, this indicates that the former exhibits better generalization capacity. The ensemble learning techniques and the GLM presents a reduced computational complexity.

Biography

Artical Title: Heavy metals contamination in two species of medicinal plants in the Iranian market

Abstract

Global threat resulting in heavy metal contamination of medicinal plants is considered a serious concern. The quantitative evaluation of four heavy metals, lead (Pb), cadmium (Cd), zinc (Zn), and copper (Cu), was investigated frequently sold medicinal plants in the markets of Iran. Two medicinal plants, Mentha piperita L. and Zataria multiflora Boiss. Were selected from six different herbalists of six districts of Shiraz, Iran. The dissolution of the sample was performed by a conventional wet acid digestion method, and heavy metal levels were determined using Polarograph. Statistical Analysis was used by SPSS.21. According to the achieved results in M.piperita the levels of Zn, Cd, Pb, and Cu were in the range of 2.66 ± 0.76 mg/kg, 0.017 ± 0.009 mg/kg, 0.092 ± 0.069 mg/kg, and 0.237 ± 0.080 mg/kg, respectively. The concentrations of Zn, Cd, Pb, and Cu in Z. multiflora samples were 1.46 ± 0.74 mg/kg, 0.019 ± 0.004 mg/kg, 0.11 ± 0.05 mg/kg, and 0.41 ± 0.17 mg/kg, respectively. There was a correlation between Zn with Cu in our finding (r = 0.9). Based on these results, we found that the concentration of heavy metals in these two medicinal plants was not more than the standard concentration reported for similar plants. It appears that these plants are generally safe in usual doses. The finding of this study can be used to determine standard heavy metals limits in M.piperita and Z.multiflora in future studies.

Biography

Artical Title: Synthesis of 45S5 bioactive glass-ceramic using the sol-gel method, catalyzed by low concentration acetic acid extracted from homemade vinegar

Abstract

In this paper, two different type of 45S5 bioactive glass-ceramic were compared. Both of them were prepared using the sol-gel method, with two different catalysts: 2 M nitric acid (NACBG) and 10 mM vinegar. Homemade vinegar (HMV) extracted from apples which contained up to 5% acetic acid, as an affordable and low concentration catalyst, was used for the synthesis of 45S5 bioactive glass ceramic called Homemade Vinegar Catalyzed Bioactive Glass (HMVCBG). The substitution of 2 M nitric acid by 87 mM acetic acid strongly reduces the concentration of the acid solution necessary for being a catalyst. The effect of these two catalysts on the structure, morphology, and properties of the bioactive glass-ceramics were investigated. Scanning electron microscopy (SEM) with energy dispersive X-ray spectroscopy (EDXS) and Brunauere Emmette Teller (BET) were used to assess surface characteristics and specific surface area, which showed more uniformity and more specific surface area in HMVCBG. Crystallinity and composition were analyzed by X-ray diffraction (XRD), X-ray fluorescence (XRF) and Furrier transform infrared spectroscopy (FTIR) which showed some crystalline phases in BG. In-vitro bioactivity was studied in Phosphate Buffer Saline (PBS) and SEM results showed that HMVCBG has a more uniform hydroxyapatite layer and formation occurs more quickly. This due to the fact that hydroxyapatite is dissolved at a lower rate at higher pH values and it takes longer to form at a higher pH. HMV can form more numerous porosities and a more specific surface area because of higher pH of acetic acid. Hence, PBS solution penetrates to the depth of HMVCBG and hydroxyapatite nucleation form in more spots in the depth of HMVCBG. Thus, HMVCBG has a higher bioactivity level than NACBG.

Biography

Artical Title: Analysis and examination of aluminum sheets suitable for automotion body: Ultrasonic testing, signal processing, simulation

Abstract

There are many changes in the automotive industry, today. All aluminum sheets used in the automotive body must have good weldability. In this article, we will test the spot welding on 6 types of 5XXX and 6XXX aluminum sheets. These sheets have been selected as the best sheet suitable for the automotive body after welding test on all sheets. This test was examined by ultrasound. The signals obtained from the ultrasound wave test do not have accurate results for better sheet determination. For this purpose, signal processing was performed on the obtained signals in order to detect sheet defect. By simulating these sheets, a comparison is made between the experimental test and the simulation, which can be used to make the best decision about the chosen sheets. The status charts of these sheets have been reviewed and it is easy to select the sheets that have been tested in the shortest time. Generally, findings indicated that the best suitable sheets in automotive bodyare type of 5XXX aluminum sheets.

Biography

Artical Title: Inulin enriched wheat bread: Interaction of polymerization degree and fermentation type

Abstract

Inulin enrichment of wheat bread is important in improving its nutritional quality. Despite the preference of inulin enrichment of wheat bread, its efficiency may be frustrated by the inulin loss through bread making process. In this study, we aimed to investigate the nutritional and technological functionality of inulin enriched wheat bread. The different fermentation process [common yeast (Y) and mixed fermentation based on sourdough (MFSD)] were used to leaven wheat breads enriched with inulin at three different degree of polymerization (DP) as short chain, long chain and native. Inulin was replaced at 10% w w−1. Despite the gluten dilution impacts induced by inulin replacement, it has been alleviated by long chain inulin incorporation and MFSD in which no significant difference has been observed regarding its specific volume and textural assessment by the control sample. The most fructan hydrolysis occurred through baking process of wheat breads containing short chain inulin in the presence of MFSD reaching losses up to 41% after baking process. Inulin loss ratio is dependent to the type of fermentation process and polymerization degree of inulin. Results obtained in this study may provide further insight to inulin enrichment of wheat bread from technological and nutritional points of view.

Biography

Artical Title: Neurotoxicity of silver nanoparticles in the animal brain: A systematic review and meta-analysis

Abstract

Objective: About 30% of all nanoparticle products contain silver nanoparticles (AgNPs). With the increasing use of AgNPs in industry and medicine, concerns about the adverse effects on the environment, and the possible toxicity of these particles to primary cells and towards organs such as the brain and nervous system increased. In this paper, the toxicity of AgNPs in neurons and brain of animal models was investigated by a systematic review and meta-analysis. Methods:The full texts of 26 relevant studies were reviewed and analyzed. Data from nine separate experiments in five articles were analyzed by calculating the standardized mean differences between viability of treated animals and untreated groups. Subgroup analysis was conducted. In addition, a systematic review provided a complete, exhaustive summary of all articles. Results:The results of the meta-analysis showed that AgNPs are able to cause neuronal death after entering the brain (standardized mean difference (SMD) = 2.87; 95% confidence interval (CI) 2.1–3.61; p < 0.001). AgNPs sized smaller or larger than 10 nm could both cause neuronal cell death. This effect could be observed for a long time (up to 6 months). Neurons from embryonic animals whose mothers had been exposed to AgNPs during pregnancy were affected as much as animals that were themselves exposed to AgNPs. Toxic effects of AgNPs on memory and cognitive function were also observed. Studies have shown that inflammation and increased oxidative stress followed by apoptosis are likely to be the main mechanisms of AgNPs toxicity. Conclusion: AgNPs can enter the brain with a long half-life and it can cause neuronal death after entering the brain. AgNPs can manifest proinflammatory cascades in the CNS and BBB. Some toxic effects were detected in the cerebral cortex, hypothalamus, hippocampus and others. Studies have shown that inflammation and increased oxidative stress lead to apoptosis, the main mechanism of AgNPs neurotoxicity, which can be caused by an increase in silver ions from AgNPs.

Biography

Artical Title: Comparison of strength and mechanisms of stabilized samples of coarse and fine-grained soils with cement kiln dust

Abstract

Road pavement soils have not had sufficient resistance in most road construction projects. Therefore, instead of substituting high-strength soils for base soils, cement kiln dust like stabilizers can be used that are not only inexpensive but also environmentally friendly. In this research, stabilization of coarse-grained sandy soils (SP) and silty fine-grained soils (SM) using different percentages of 5, 10, 15 and 20% of cement kiln dust has been investigated. Standard compaction and uniaxial compressive strength tests as well as direct shear test with two types of soil mentioned with different percentages of cement kiln dust at the time of curing and 7, 14 and 28 days have been performed. The results show that by adding 20% of CKD to sandy soil, the resistance has increased 11.3 times than of the base soil, while with the same percentage of CKD, the uniaxial strength of silty soil has increased by 9.8. Therefore, the CKD stabilizer for coarse-grained sands has a greater effect than fine-grained, which can be attributed to the better locking of sand grains in the effect of increasing the CKD than silty soil. Also, microstructural experiments including XRD, SEM, EDAX, FTIR have been performed for stabilized samples and base soil and the results have shown that changes in the peak Formation of CSH gels and coherent structure related to sandy soil have been observed that confirms this issues.

Biography

Artical Title: Assessment of heavy metals in agricultural and background soils around future copper mine, using enrichment factor and Geoaccumulation index, Iran

Abstract

Heavy metals are pollutants released into different parts of the environment such as soil and plants due to natural and anthropogenic origin. There is a possibility of water, soil, and plant pollution in Darreh Zereshk area in the near future. To assess the soil contamination and determine the origin of selected heavy metals, enrichment factor (EF) and geoaccumulation index (Igeo) were conducted. To aim this purpose a total of 30 agricultural soil samples and 12 background soil samples were collected from Darreh Zereshk area in central Iran which is going to be one of the richest copper mines in Iran and the Middle East. Accordingly, total and soluble concentration of heavy metals (Cu, Pb, Zn, Mn, As, Fe, Ni and Cr) and some Physico-chemical properties of soils were determined. According to the Igeo result Dareh Zeresh village is moderately to heavily contaminated with Cu (2.16), Hasan Abad and Bishe villages are moderately contaminated (1.21, 1.04) and Darreh Gazeh and Dehshir villages are uncontaminated to moderately contaminated (0.01, 0.13), which can be justified by the presence of rich copper deposit in the area and the distances of each village from that. High EF factors for Cu, Zn and especially for Pb as it is not an essential micronutrient, indicate a considerable enrichment caused by pollution. Contamination of the agricultural soils is more severe for Pb, Cu and Zn and less severe for As. The origin of Ni and Cr does not seem to be anthropogenic.

Biography

Artical Title: An investigation into the laser forming process of perforated tubes

Abstract

Tube bending is always a challenge in conventional bending. Usually, an internal plug is inserted inside the tube, and bending happens. However, a laser beam can also be used for tube bending. The laser beam is irradiated on the tube surfaces and may result in 2D or 3D tube bending. The laser tube bending process (LTBP) process is a thermal non-contact process for bending tubes with less springback and less thinning of the tube. In this work, the laser forming process of perforated tubes is studied numerically. For this purpose, the finite element simulations are performed in ABQUS software. In addition, the effects of process parameters such as laser output power, laser scanning speed and laser beam diameter on the characteristics of laser formed tubes are studied.

Biography

Artical Title: The characterization and mineralogical studies of thorium ore deposit in Choghart, Yazd, Iran to evaluate beneficiation prospects

Abstract

This paper investigates the mineralogical characterization of a thorium ore taken from the Choghart iron mine, Yazd, Iran. The mineralogical studies revealed that the main thorium content mineral of the ore was thorite; and it was mainly disseminated as a valuable mineral in different forms in minor quantity along the edge or within the intergranular spaces of gangue silicate minerals and magnetite. The XRF analysis of a radiometric sorting concentrate sample indicated that the sample contained approximately 0.25% thorium oxide, 66.28% silicate compositions, 9.14% iron oxide, and significant amounts of rare earth elements. Sink and Float tests of different sizes of the sample using diiodomethane and bromoform resulted in a 2.22% concentrate with 85.7% thorium recovery. Liberation degree studies by SEM-EDX and image processing indicated that a size range of (-125,+75)µm was the optimum liberation size, and it was recommended for further beneficiation tests.

Biography

Artical Title: Ventilation prediction for an industrial cement raw ball mill by BNN-a conscious lab approach

Abstract

In cement mills, ventilation is a critical key for maintaining temperature and material transportation. However, relationships between operational variables and ventilation factors for an industrial cement ball mill were not addressed till today. This investigation is going to fill this gap based on a newly developed concept named “conscious laboratory (CL)”. For constructing the CL, a boosted neural network (BNN), as a recently developed comprehensive artificial intelligence model, was applied through over 35 different variables with more than 2000 records monitored for an industrial cement ball mill. BNN could assess multivariable nonlinear relationships among this vast dataset and indicated mill outlet pressure and the ampere of the separator fan had the highest rank for the ventilation prediction. BNN could accurately model ventilation factors. Since improving the milling efficiency has an essential role in machine development and energy utilization, these results can open a new window to the optimal designing of commination units for the powder technologies.

Biography

Artical Title: High density polyethylene-bismuth oxide nanocomposite: A dental shield applied in radiography centers

Abstract

Due to the importance and approach of lead-free radiation shields, which has received serious attention in recent years, in this research, radiation shielding characteristics of High Density Polyethylene/Bismuth Oxide (Bi2O3/HDPE) nanocomposite against the gamma rays of 241Am source with 59 keV photon energy was investigated by MCNP, XCOM simulations and experimental methods. First, the quantities of linear attenuation coefficient (µ), mass attenuation coefficient (µ/ρ), Half-Value Layer (HVL) and Tenth-Value Layer (TVL) related to different weight percentages of the composite were simulated using the MCNP code. Then, the simulation results were validated with XCOM software data, which indicated the high accuracy of the simulation. The simulation results showed that by increasing the energy of the incident photons, the attenuation coefficient of the photons was decreased. At the end of the simulation phase, 60 wt% Bi2O3/HDPE composite with density of 2.01 g/cm3, µ=5.9193 cm-1, µ/ρ=2.945 cm2/g, HVL=1.2 mm, TVL=3.9 mm was selected to fabricate a jaw shielding material at 59 keV. With increasing the Bi2O3 weight percentage in the polymer matrix, the effective atomic number and density of the composite will be increased accordingly, thus the amount of attenuation coefficient will be increased and the HVL and TVL values in the mentioned energy will be decreased. In the experimental phase, 60 wt% Bi2O3/HDPE nanocomposite was fabricated via soloution method. Then, various tests such as FESEM and XRD were performed on the samples, which indicated good dispersion states of bismuth oxide nanoparticles in the polyethylene substrate. After fabrication of the samples, the quantities of µ, µ/ρ, HVL and TVL were measured. Results showed an acceptable correlation with simulated values with MCNP code and XCOM software.

Biography

Artical Title: SnO2 nanoparticles or reduced graphene oxide nanocomposite for fast ethanol vapor sensing at a low operating temperature with an excellent long-term stability

Abstract

Pristine SnO2 nanoparticles (NPs) and its composite with reduced graphene oxide (SnO2 NPs/rGO) have been successfully synthesized using a facile hydrothermal method. Prepared samples are characterized by X-ray diffraction, high-resolution transmission electron microscopy, X-ray photoelectron spectroscopy, Brunauer–Emmett–Teller analysis, and Raman and photoluminescence spectroscopy. The results show that the average crystallite size of SnO2 NPs with tetragonal rutile structure decreased from about 14 to about 8 nm during the formation of SnO2 NPs/rGO nanocomposite. The resultant SnO2 NPs/rGO nanocomposite exhibits high surface area of 128.52 m2/g and large pore volume of 0.14 cm3/g with uniform pore size of 4.39 nm. The existence of electronic interactions caused by the formation of p–n heterojunctions between p-rGO and n-SnO2 NPs is confirmed by analysis results. SnO2 NPs/rGO nanocomposite sensing responses toward 600–1700 ppm of ethanol vapor at 130℃ are about 14–33 times higher than those of pristine SnO2 NPs at 210℃. The nanocomposite sensor exhibits very low response time of below 3 s, good selectivity, and excellent long-term stability with the response decay of about 4% after 4 months. The improved sensing characteristics in SnO2 NPs/rGO nanocomposite can be attributed to the formation of p–n heterojunctions, small particles size, large specific surface area, and high porosity.

Biography

Artical Title: Evaluation of the effects of nanoparticles on the therapeutic function of platelet: A review

Abstract

Objectives: Nanotechnology and nanoparticles can be used in the blood disease monitoring and therapy. Nanoparticles have various effects on blood components and can reduce or improve the function of therapeutic platelet during the storage time. This review study was performed to evaluate the impacts of nanoparticles with various sizes and charges on platelet function and storage time. The present review contains the literature reported between 2010 and 2020. The data have been used from different sites such as PubMed, Wiley, Science Direct and on-line electronic journals. Results and discussion: The literature survey demonstrated that among various properties, size and charge of nanoparticles were critical on the function of therapeutic platelet during the storage and inhibition of their aggregation. Overall, this study described that nanoparticles with smaller size and negative charge were more effective in increasing the survival time, inhibition of aggregation and improving the function of the therapeutic platelet. Summary Based on the current review, it confirmed that nanoparticles such as dendrimer, Au, Ag and iron oxide nanoparticles with smaller size and negative charge have significant advantages for improving the efficacy of platelets during the storage chain and inhibition of their aggregation.

Biography

Artical Title: Nanotechnology, big things from a tiny world

Abstract

Gathering knowledge and technology for hello tomorrow…. Science and technology impact our daily lives, our societies, our planet. We powering deep technologies for better tomorrows and building the future of Humanity together. We believe that nanotechnology can have a global impact and solve the world’s major issues…. Nanotechnology is science, engineering, and technology conducted at the nanoscale where the atoms and molecules behave differently at the nanoscale. Making materials at the nanoscale to take advantage of enhanced properties such as higher strength, lighter weight, increased electrical conductivity, and chemical reactivity compared to their larger-scale equivalents. However, there is a major bottleneck in transforming these technologies into impactful products ... but no worry this will be our mission. Our mission is to BUILD a bright TOMORROW.

Biography

Artical Title: Mechanical properties and microstructure evolution in arc stud welding joints of AISI 1020 with AISI 316L and AISI 304

Abstract

The mechanical properties and microstructures of dissimilar arc stud weldments of AISI 316L/AISI 1020 and AISI 304/AISI 1020 were investigated. Welding currents of 400, 600 and 800A and welding time of 0.2, 0.25, 0.3, 0.35, 0.4 and 0.45 second were employed. Maximum torque strength of 77N.m was registered with 600A and 0.25 second for 316L/AISI 1020 joints with failure occurred away from the fusion zone (FZ) within the stud shank. Whereas for AISI 304/AISI 1020 joints, the maximum torque strength was 68Nm recorded with 600A and 0.35 second and the failure occurred at FZ. For both dissimilar joints, the presence of chromium carbides and equiaxed grain structures are the direct caused for the augmentation of hardness at the FZ. The microstructure of FZ was completely re-solidified of the austenite phase.

Biography

Artical Title: Morphological, magnetic, optical, surface potential, and H2S gas sensing behavior of polypyrrole nanofibers

Abstract

The effect of the oxidant-to-monomer (O/M) molar ratio on the morphological, magnetic, optical, and surface potential performance of polypyrrole nanofibers (PPy NFs) has been studied. PPy NFs were prepared by chemical polymerization of pyrrole at 5 ˚C, then the structure of nanofibers with various diameters was determined by field-emission scanning electron microscopy (FESEM). X-ray diffraction analysis and energy-dispersive x-ray spectroscopy were used to determine the composition of the PPy NFs in the prepared nanostructures. The magnetic hysteresis loop of PPy NFs showed soft ferromagnetic behavior. The surface potential of PPyNFs was measured by Kelvin probe force microscopy, revealing that the sample with a MO:Py: FeCl3 molar ratio equal to 1: 5.6: 4 showed excellent surface potential behavior. The H2S gas sensing performance of the PPy NFs thin films with each molar ratio was also tested, revealing an enhancement with increasing oxidant concentration.

Biography

Artical Title: Green synthesis and characterize of silver nanoparticles by using leaves extract of Polyalthia Sclerophylla and their cytotoxicity studies

Abstract

This study was conducted to synthesize and characterize Silver Nanoparticles (AgNPs) using a rapid green synthesis approach. The crude extract of leaves of Polyalthia sclerophylla (CEPS) were used as a reducer and silver nitrate (AgNO3) as an initiator. Two samples were prepared and named as AgNPs-a and AgNPs-b, respectively. The prepared samples were carried out to characteristic their chemical, physical and biological properties. The first technique that used to confirm the formation of AgNPs were ultraviolet–visible spectroscopy (Uv-vis) and Energy Dispersive X-Ray Analysis (EDX). Scanning electron microscopy (SEM) and scanning transmission electron microscopy (STEM) were used to identify the morphology and size of the particles. Mg-63 human cells were used to study the cytotoxicity of the AgNPs using the Alamar blue assay. The results have been shown that, the wavelength of AgNPs-a was 436 nm, while the AgNPs-b showed at 441 nm. Prepared samples were shown spherical in their shapes according to SEM and STEM images. The size of the particles was not same, whereas, the diameter size range of AgNPs-a were from 48nm to 68 nm, while the AgNPs-b showed range from 59 nm to 77 nm. Prepared samples showed availability for the Mg-63 cells more than 89% for all concentrations after 24h. Present study has been demonstrated non-toxic prepared samples with nano-sizes which can be used safely in the medical and biological fields.

Biography

Artical Title: In vivo kinetic release of five metal ions (iron, titanium, nickel, copper and chromium) from fixed orthodontic alloys in Erbil city-Kurdistan region or Iraq

Abstract

The orthodontic kinetic release of metal ions was studied in order to have a conclusive in-vivo data for variation of metal ion concentrations with time (month) at normal oral temperature 37°C, which affects the saliva quality and quantity, pH, chemical and physical characteristics of food and liquid. The superficial break down and release of metals from the alloy brackets were investigated by scanning electron microscopy (SEM) and energy dispersive X-Ray spectroscopy (EDS) images. The kinetic release experiment of the metal ion concentrations (Nickel, Chromium, Titanium, Iron, and copper) in the saliva uptakes follow a pseudo-second-order kinetic model, the release rate of metal ions was in series Fe2+ > Ti2+ > Ni2+ > Cu2+ > Cr3+, and the highest saliva pH and flow rate were detected after one month for fixed orthodontics appliance was (7.16  0.55) and (0.88  0.55) respectively.

Biography

Artical Title: Triazole analogues as potential pharmacological agents

Abstract

Background: A large number of studies have recently reported that, because of their significant biological and pharmacological properties, heterocyclic compounds and their derivatives have attracted a strong interest in medicinal chemistry. The triazole nucleus is one of the most important heterocycles which has a feature of natural products as well as medicinal agents. Heterocyclic nitrogen is abundantly present in most medicinal compounds. The derivatization of triazole ring is based on the phenomenon of bio-isosteres in which substituted the oxygen atom of oxadiazole nucleus with nitrogen triazole analogue. Main text: This study focuses on recent synthetic procedure of triazole moiety, which comprises of various pharmacological activities such as antimicrobial, anticonvulsant, anti-inflammatory, analgesic, antitubercular, anthelmintic, antioxidant, antimalarial, antiviral, etc. Conclusion: The study highlights the current status of triazole compounds as different multi-target pharmacological activities. From the literature survey, triazole is the most widely used compound in different potential activities.

Biography

Artical Title: A systemic research based study on a survey of customer s choice of toothpaste in the Rajasthan population

Abstract

Objective: The customer’s choice of toothpaste may seem a light topic to be discussed but sheds light on the knowledge of dental hygiene among the customers of various ages, ethnicity, geographical locations and brands. This survey discusses the factors that influence the customer’s choice as well as the most common brand preferred among various age groups and also what the customers desire in their toothpastes. Methods: A survey was conducted among 300 people from different parts of India. The questionnaire used was kept consistent and covered various aspects from dental hygiene to toothpaste preferences to help with further studies of toothpaste qualities to generate customer satisfaction. Results: Various pie charts give information regarding the questions answered by the people, and further evaluation and studies on them have been done to give detailed results. Conclusion: This information can help understand the type of oral hygiene methods that patients feel comfortable to approach and use. It can also help to understand the knowledge level of patients regarding dental hygiene and thus make products with appropriate features to make it more approachable to the customers.

Biography

Artical Title: Geotechnical characterization of red mud waste material for road construction

Abstract

Red mud waste material is a by-product generated during the extraction of alumina from bauxite ore by Bayer process. Million tons of red mud is being produced/piled near by the producing industry in India which is increasing day by day and causing serious issue related to proper disposal as it has very limited application. Accordingly, study on red mud was carried out to explore the possible application in road construction. Physical/chemical characterization was carried out to examine the morphology and chemical constituents. Toxicity characteristics leaching procedure (TCLP) test was also carried out to know the hazardous nature of the material. Stress-strain behavior was analyzed and compared with other similar materials along with other geotechnical characteristics. To study the stress- settlement behavior, laboratory physical small scale plate load test was carried out simulated with traffic loading and the same was validated by numerical finite element method. It was observed that red mud has lattice and impervious microstructure of silt and clay size fine particles. It mainly contains manganese, chromium, vanadium, barium, lead, copper and zinc with traces of other elements. Concentration of heavy metals was within the permissible limit which indicated that it is a non-hazardous material. It has high values of dry density (21.28 kN/m3), California Bearing Ratio (25%) and angle of internal friction (44°) compared to soil which makes it suitable for road construction. It was observed that its stress-strain behavior is similar to conventional materials (soil). Modulus value indicates that it is a stiff material which leads to less settlement as an embankment fill constructed at maximum dry density and optimum moisture content.

Biography

Artical Title: Adsorption and equilibrium studies of methyl orange on tamarind shell activated carbon and their characterization

Abstract

Biomass-derived carbon with high surface area and tunable pore structures are attracted due to their applications in several fields. A facile one-step approach for preparing activated porous carbon from tamarind shells and ammonium chloride is presented here. The activated carbon from the tamarind shell (ACTS) was characterized using FTIR, TGA/DTA, and SEM to understand the functionalities present in the material's surface, stability, and surface morphology. The ACTS material was employed as an adsorbent to remove synthetic dyes and a potential applicant in removing organic compounds from industrial wastewater. The effect of dosage with the concentration of dye materials is studied using Langmuir and Freundlich isotherm models. The Langmuir model showed a better fit with a maximum adsorption capacity of 24.3 g.L-1.

Biography

Artical Title: Electromechanical bandgaps in piezo-embedded mechanical metamaterials

Abstract

Elastic mechanical metamaterials are the exemplar of periodic structures. These are artificially designed structures having idiosyncratic physical properties like negative mass and negative Young’s modulus in specific frequency ranges. This unusual dynamic behavior is frequency contingent, which modulates wave propagation through these structures. Locally resonant units in the designed metamaterial facilitate bandgap formation virtually at any frequency for wavelengths much higher than the lattice length of a unit. Here, we analyze the band structure of piezo-embedded negative mass metamaterial using the generalized Bloch theorem. The addition of the piezoelectric material at the resonating unit increases the complexity of the solution. The results elucidate, the insertion of the piezoelectric material in the resonating unit provides better tunability in the band structure for simultaneous energy harvesting and vibration attenuation. Non-dimensional analysis of the system gives physical parameters that govern the formation of mechanical and electromechanical bandgaps. Thus, broader bandgap generation enhances vibration attenuation, and energy harvesting can be simultaneously available, making these structures multifunctional.

Biography

Artical Title: Hybrid organic-inorganic perovskite-based electronic devices

Abstract

The success of the organic-inorganic hybrid perovskite materials for the solar cell since 2009 has also extended to other applications such as memory devices, ultrafast switches and light - emitting diodes (LED), field-effect transistors, lasers, detectors, etc. Herein, we leverage the unwelcome ion-migration in perovskites to unlock new opportunities for resistive switching using layered Ruddlesdsen-Popper perovskites (RPP) and explicate the underlying mechanisms. The ON/OFF ratio of RPP-based devices is strongly dependent on the layers and peaks at n ̅ = 5; demonstrating the highest ON/OFF ratio and minimal operation voltage. Long data retention even in 60% relative humidity and stable write/erase capabilities exemplify their potential for memory applications. Impedance spectroscopy reveals a chemical reaction between migrating ions and the external contacts to modify the charge transfer barrier at the interface to control the resistive states. Our findings explore a new family of facile materials and the necessity of ionic population, migration and their reactivity with external contacts in devices for switching and memory applications. In parallel, we unravel the potential of the D2O as a solvent additive to enhance the PCE ~ 21% in triple cation based perovskite solar cells with stronger stability. Ultrafast optical spectroscopy confirms trap states passivation increased carrier recombination lifetimes and enhanced charge carrier diffusion lengths in our deuterated samples. Fourier transform infrared spectroscopy and solid-state nuclear magnetic resonance (NMR) spectroscopy validates N-H2 group as the preferential isotope exchange site. Furthermore, first-principles density functional theory calculations reveal a decrease in PbI6 phonon frequencies in the deuterated perovskite lattice. This stabilizes the PbI6 structures and weakens the electron-phonon coupling, yielding higher electron mobility. Importantly, these findings prove that selective isotope exchange opens new opportunities for tuning perovskite optoelectronic properties.

Biography

Artical Title: Image encryption using microcontroller

Abstract

The encryption of RGB color image using microcontroller ATMEGA 32 is studied in the present paper via synchronization with one-dimensional chaotic map. Two microcontrollers are used to execute encryption and decryption algorithms under synchronized condition to demonstrate the cryptosystem. Both the microcontrollers run the dimensional logistic map and they become synchronized through open plus closed loop (OPCL) coupling. Under synchronized condition, the stored data of the input image in one microcontroller is encrypted with its generated chaotic sequences and transmitted to the remaining microcontroller, known as the receiver. The receiver microcontroller decrypts the encrypted data and stores in its memory. After decryption of the full image data it is forwarded to LCD display to visualize the decrypted image. The strength of security of the algorithm is analyzed by a number of cryptanalysis techniques like, correlation coefficient, histogram analysis, information entropy, NPCR, UACI, MAE, etc. should give clear indication of the objectives, scope, results, methods used, and conclusion of your work. One figure and one table can be included in your results and discussions.

Biography

Artical Title: Experimental studies on coir geotextile reinforced low volume rural roads

Abstract

This paper proposes the practical implementation of improvement of weak subgrade soil by using coir geotextile. The test track is subjected to various tests to study the improvement in structural behaviour of the reinforced pavement. The total length of the road was divided into three sections. This was done to analyse the performance of coir reinforced pavements with sections of different thickness and types of coir geotextiles. Coir geotextiles with mass density 740 gsm (designated as CGT1) and 365 gsm (designated as CGT2) of widths 6 m and 8 m were used. The study explores the improvement in elastic modulus that could be attained by the subgrade reinforced with coir geotextiles through field experiments like geogauge and static plate load tests. The culmination of this work is the preparation of design guidelines for coir geotextile reinforced low volume roads. Hence baseline design inputs that are obtained from the above mentioned tests were used for the numerical analysis using KENPAVE software. The data reveal that the elastic modulus of the subgrade has multiplied appreciably when reinforced with coir geotextile, which would help in increasing the service life of the pavement. The same has been reflected in the distress survey results also. The improvement attained is 1.41 and 1.25 times of the elastic modulus of the parent soil, with coir geotextile of mass per unit are 740gsm and 365gsm, respectively. The modified subgrade elastic modulus has been inputted in the KENPAVE software and analysed in order to prepare a design chart for coir geotextile reinforced low volume roads.

Biography

Artical Title: Electrophoretic study to detect the biomolecules using graphene-based field effect transistor

Abstract

Graphene based sensor devices have been investigated significantly and results of different chemicals decorated on a graphene sheet were identified by the transfer characteristics. The GFET based device was fabricated by the mechanical exfoliation method with an inbuilt reference electrode acting as an electrolyte gate electrode. Devices show good transfer characteristics, which depend on the surface morphology of the material and substrate. During fabrication of the device, the substrate morphology was disturbed in appropriately by the contamination of the surface. In the present study, monolayer Graphene Field Effect Transistor (GFET) was driven with hydrophobic Hexamethyl Disilazane (HMDS) layer. Fabrication of GFET device on the hydrophobic substrate enhances the effective ambipolar behaviour. The fabricated devices were used for direct adsorption of single- and double-stranded DNA. Detection of disease-related gene expression by DNA hybridization is one of the useful diagnostic methods. In this study a monolayer graphene field effect transistor (GFET) was used for the detection of a particular single-stranded DNA (target DNA). The VDirac was shifted to the negative direction in the probe DNA immobilization. In recent cases of cancer therapy, such as DNA based therapies, messenger RNA (mRNA) is also used as alternatives. mRNA has a good capability to classify cancer subtypes. The device can support mRNA detection and provides the best platform for cancer detection. Furthermore, the monolayer GFET is driven by an inbuilt top-gate for detecting the pH of the contacting buffer solution. The fabricated devices are also used to detect the protein samples decorated on the channel surface. Detection of protein is the most important diagnostic method for immune regulation and metabolism. The GFET device detects the effect of hydroxide ions on a graphene surface. The sensitivity of the device was estimated the device performance. Fabrication of this kind of compact GFET device with inbuilt gate enables low-cost, real-time sensitive amperometric sensors, which enhances the effective sensing and user-friendly in the platform of biosensing applications.

Biography

Artical Title: Biomaterial material based devices for controlled release of agrochemicals

Abstract

Explosion in population is a big threat. This has resulted in food scarcity. Rain deficiency has caused soil desertification. Smart materials based controlled release devices can solve the problem of desertification. Such materials can be used effectively for the sustained and controlled release of agrochemicals and can provide alternative to traditional chemical fertilizer treatment due to their ability to release the agrochemicals under controlled conditions. These materials can also conserve the moisture in the soil for a long period. They are of great importance in reducing the underground water pollution as well as soil pollution. Thus, such materials are of great importance from Farmer’s economy point of view and provide a better way to solve problems related with agricultural issues. The present work includes the fabrication of polymeric materials of natural origin for their applications in agricultural sectors.

Biography

Artical Title: Synthesis and characterization of shear thickening fluids for soft armours applications

Abstract

Body armour for the military has traditionally been designed to provide protection against fragmentation and ballistic threats. Armours have traditionally been protected based on steel which gives rise to extremely heavy structure and weight, provides logistical problems and discomforts due to transport to a battle site. Soft Armour is a ballistic protection technology that provides security for people in vulnerable environments. Presently, high performance fibres have been used to make soft ballistic body armors for the realization of lightweight, flexibility and comfort. But inclusion of these fibers has resulted in significant improvements in the cost of body amours. The Shear thickening fluid (STF) has attracted attention for impact protection due to its unique properties subject to impact. STF is a non-Newtonian fluid and shear thickening behaviour is triggered by a sudden increase of shear rate to the STF, which causes colloidal dispersions to concentrated exhibiting an abrupt increase in viscosity. In this perspective, the present research work is focused on the preparation and characterization of a novel shear thickening nanocomposite fluid to improve the stab resistance and to resist the penetration of bullets in soft wearable armours. The present work endeavours towards the development and characterization of ZnO nanoparticle dispersed shear thickening fluid. The shape and size dependency of the nanoparticles on the shear stress behaviour of shear thickening fluid (STF) was studied. The optimized composite STF was coated on polypropylene (PP) woven fabric and further characterized for its stab and ballistic impact resistance.

Biography

Artical Title: Graphene-silver nanoparticles loaded cement based material improves the mechanical, antimicrobial properties

Abstract

Modern architecture was based upon new and innovative technologies of construction, particularly the use of glass, steel and reinforced concrete. Modern infrastructure requires structural components with higher mechanical strength and greater durability. Now a day’s researcher in concrete technology working on innovative composite material incorporation with nanomaterials to improve cement-based materials mechanical properties. Some such nanomaterials include nano-silica (nano-SiO2), nano-alumina (nano-Al2O3), nano-ferric oxide (nano-Fe2O3), nano-titanium oxide (nano-TiO2), carbon nanotubes (CNTs), graphene and graphene oxide despite the many available studies on the evaluation of the influence of nanomaterials on the properties of cement-based composites, the effects of some nanoparticles have not yet been fully recognized. Among the unrecognized nanomaterials is graphene-silver nanocomposite. The literature devoted to this subject is limited. This paper reviews state-of-the-art research carried out on the effect of graphene-silver nanocomposite on the properties of cement-based composites. Detailed descriptions of the processing, microstructures (hydration products), properties (hydration, workability, mechanical and functional properties, and durability).Foremost new property we found in this material, which enable the antimicrobial activity in cement based composite material.

Biography

Artical Title: Vibration based micro-scale piezoelectric energy harvesting system

Abstract

The growth in the field of VLSI has given a new range of portable electronic gadgets to mankind and connected the whole world with communication devices. The success of portable electronics devices is based on energy needs and power consumption. The energy need is accomplished with the batteries. The advancement in fabrication industry is doubling the number of transistors in every 18 months, while the energy density of batteries is comparatively flat during an equivalent period. Moreover, batteries contain heavy metals that are toxic and hazardous. The alternative to traditional batteries is to make use of the parasitic mechanical vibration energy available locally in the atmosphere. Industrial devices, cars, structures, and human movement release mechanical vibrations which could be excellent sources for collecting small amounts of power without impacting the source itself. The use of piezoelectric, electromagnetic and electrostatic transducers can convert mechanical vibration energy into electrical energy. Piezoelectric transducers offer more viable option because of their high energy density. Important factors governing the performance of piezoelectric energy harvester are choice of material, volume, shape, resonance frequency and output power. The objective of this research work is to design a piezoelectric energy harvesting system with a wide bandwidth and a current amplification energy harvesting circuitry which would be capable enough to autonomously power micro-scale devices throughout their lifetime. Through the simulative analysis it has been concluded that the stress generated on a cantilever is more than any other mechanical structures. A bimorph cantilever harvester is constructed with silicon substrate and zinc oxide as piezoelectric material. Volume of the bimorph is 341.4mm3 which is significantly less than micro-scale maximum volume of 1000mm3. The studies concluded to have a thin film and a longer device which could provide higher power and better matching of resonance frequency with ambient vibration sources. The output power of 0.5mW across a 4MΩ resistor produced by the bimorph piezoelectric cantilver energy harvester at around 90Hz resonance frequency. A novel piezoelectric energy harvester has been proposed in this work based on a conventional seesaw mechanism. See-saw harvester is linear in design compared to other broadband energy harvester which have nonlinearity in structures with magnets, stoppers introduced. The displacement, charge and voltage sensitivity of the proposed harvester is improved by 76%, 12% and 8% respectively. The bandwidth of the proposed structure is also large as compared to the conventional design. The proposed design has a better sensitivity bandwidth product per unit volume of 33.23%, 10.20% and 22.70%, in terms of displacement, charge and voltage respectively.

Biography

Artical Title: UWB MIMO Antennas

Abstract

The overlapping of narrowband communication systems with the UWB spectrum makes radio signals interfere. Therefore, the proposed antenna is designed with triple-band rejection capability. The antenna consists of four feedlines and a common ground surface which acts as the main radiator. The four elements of the antenna are kept orthogonally to exploit polarisation diversity, resulting in high isolation. The presented antenna is having size=44×44 mm2 and printed on FR4 substrate. A spiral slot was introduced in the ground surface which behaves similarly as a band-stop filter (BSF) and rejects the X-band for Uplink Satellite Communication. For rejecting WiMAX and WLAN band, the modified trident shape of the microstrip line is used. Also, Defected Ground Structure (DGS) is used for the isolation (>23 dB) enhancement. The proposed antenna is used for small handheld communication devices. A planar Ultra-Wideband (UWB) wearable Multiple Input Multiple Output (MIMO) antenna is designed for on-arm wearable Wireless Body Area Network (WBAN) applications. This antenna is designed on a 100% cotton cloth substrate. The two-port MIMO antenna has a dual spinning wheel shape like radiators with the partial ground and microstrip feedings. The two partial grounds are connected to a rectangular strip to have common ground. The complete surface area of the antenna is 40 × 70 mm2. In comparison with recently published papers in the same research area, the bending and SAR analysis are also done to estimate the performance of this wearable antenna, which is the novelty of this research work. For entire UWB bandwidth, S–parameters, gain, efficiency, and diversity parameters (Channel Capacity Loss (CCL) and Envelope Correlation Coefficient (ECC)) and far-field simulations are done for all cases such as flat, bend, on body antenna, which demonstrates the appropriateness of the presented antenna to be operated to the human arm.

Biography

Artical Title: Investigation on corrosion properties of bright Zn-Ni alloy coated mild steel

Abstract

Electrodeposition is a renowned surface-modification method to get better surface characteristics, both functional and decorative properties of a broad diversity of materials. Recently, zinc and its alloy coatings are finding several applications, as a sacrificial metallic coating for the protection of mild steel. Zn-Ni alloy coating is the most commonly exploited in commercial applications and it exhibits significantly higher corrosion resistance ability and superior surface morphology than pure zinc. It is used as a replacement for toxic and expensive cadmium coatings. Literature survey revealed that zinc-nickel alloy coating without brightener is dull, unattractive and uneven and has comparatively less corrosion resistance ability. Hence, brighteners are gaining significance. They are found to adsorb on cathode surface (Mild Steel) and thereby modify the surface characteristics of the coating. Adsorption of brightener affects the nature of coating resulting in refined coating, which in turn alters the surface properties especially corrosion resistance of steel. A new brightener CG was synthesized by condensation of Cysteine Hydrochloride and Glutaraldehyde. Electrodeposition of Zn-Ni alloy from Sulphate bath was done in presence of CG. Corrosion studies were carried out using Electrochemical Impedance spectroscopy and Potentiostatic techniques. Surface morphology was studied using SEM, Reflectance spectroscopy and X-Ray Diffraction. Brightener CG was successful in giving bright zinc-nickel alloy deposits. Corrosion techniques confirmed increase in corrosion resistance and protection ability of bright zinc-nickel coatings. Surface studies revealed enhancement of fine grained nature of zinc-nickel alloy crystallites. XRD studies depicted the presence of η and γ- phases of pure zinc and zinc-nickel alloy respectively in the deposits. CG is accountable for increasing the corrosion resistance ability of bright zinc-nickel depositsince refined grain structure is closely associated with corrosion resistance property. It changes the orientation of Zn-Ni alloy crystallites which is accountable for brightness. CG can act as an efficient brightener and can be commercially used.

Biography

Artical Title: Aluminum metal-organic framework nodes support single-site nickel (II)-hydride catalyst for chemoselective hydrogenation of nitro and nitrile compounds

Abstract

The development of chemoselective and heterogeneous earth-abundant metal catalysts is essential for environment-friendly chemical synthesis. We report a highly efficient, chemoselective and reusable single-site nickel(II) hydride catalyst based on a robust and porous aluminum metal-organic frameworks (DUT-5) for hydrogenation of nitro and nitrile compounds to the corresponding amines under mild conditions. The nickel hydride catalyst was prepared by the metalation of aluminum hydroxide secondary building units (SBUs) of DUT-5 having the formula of Al(µ2-OH)(bpdc) (bpdc = 4,4’-biphenyldicarboxylate) with NiBr2 followed by the reaction with NaEt3BH. DUT-5-NiH has a broad substrate scope with excellent functional group tolerance in the hydrogenation of aromatic and aliphatic nitro and nitrile compounds under 1 bar H2, and could be recycled and reused at least 10 times. By changing the reaction conditions of the hydrogenation of nitriles, symmetric or unsymmetric secondary amines were also afforded selectively. The experimental and computational studies suggested reversible nitrile coordination to nickel followed by 1,2-insertion of the coordinated nitrile into nickel-hydride bond occurring in the turnover limiting step. The zeroth-order dependence of the reaction rate on the pressure of H2 allowed progressing all the reactions under ambient hydrogen pressure. This work highlights the potential of MOF-based single-site earth-abundant metal catalysts for practical and eco-friendly chemical feedstocks production due to their low cost, excellent stability and reactivity, and the usage of cheap and atom-economical reductant hydrogen.

Biography

Artical Title: Impact of surface functionalization on GaN or ZnO nanostructure based hetero-interfaced UV photodetectors

Abstract

The pandemic COVID-19 is causing significant economic, healthcare and social disruption world-wide. The protective vitamin-D synthesis by the Ultraviolet-B (UVB) radiation in human beings found to be major break-through for the betterment of mankind. Therefore, it is inspiring to emphasis on utilization of UVB and fabricates energy efficient and durable ultraviolet-photodetectors (UV-PDs). Henceforth, the presented study showcased the fabrication of unique tapper ended GaN-Nanotowers (GaN-NTs) based highly efficient UV-PDs. Thereby, hexagonal stacked GaN nanocolumnar structure (nanotowers) exhibits higher photocurrent generation which significantly enhances its responsiveness towards UV and leads to outstanding performance of the device. The fabricated detector display low dark current (~ 12nA), high ILight/IDark ratio (> 104), fast time-correlated transient response (~ 433µs). A very high photo responsivity (R) of 2.47 A/W in self-powered (zero applied bias) mode of operation is reported. While in photoconductive mode, the R is observed to be 35.4 A/W@-3V along with very high external quantum efficiency (EQE) is ~ 104%, lower noise equivalent power (NEP) ~ 10-13 WHz-1/2 and excellent UV-Vis selectivity. Besides this, the role of increased thickness of AlN-buffer layer and GaN-NTs height is also realized in terms of enhanced performance PDs. This variation in device geometry leads to augmented R, low NEP, and a high EQE of 88.6 to 484.77 A/W@-3V to -6V, 1.76 × 10−13 W.Hz 1/2, and 1.85 × 105 %, respectively. Moreover, for further improvisation, a hybrid interface of ZnO/GaN with unique geometry of nanostructure over nanostructure is also explored. These ZnO-NRs hybridized GaN-NTs based UV-PDs demonstrated enhancement in R value from 477 A/W to 1204 A/W@-6V. Furthermore, an impact of sensitization of chemically synthesized novel GQDs on a ZnO-NRs/GaN-NTs heterostructure-based UV-PDs is also realized. The fabricated device demonstrates an excellent R of 3200 A/W at −6 V and displays an enhancement of ~671% and ∼265% compared to its bare counterpart (GaN : 477 A/W and ZnO/GaN: 1204 A/W). In addition, the fabricated heterostructure UV-PD exhibits a very high EQE of 1.2 × 106%, better switching speed, and signal detection capability as low as ∼50 fW.

Biography

Artical Title: Estimation of service life of polymer composite in nuclear environment for shielding application

Abstract

When one puts a product into service, the ability to predict its lifetime or failure rate would be highly beneficial. The composite part should be tested in real time and in environments similar to those in which the part will be exposed. For applications, such as space applications, in radiation environment, it is expected to have about 20 to 30 years durability. In case of polymer composites, the reactive intermediates like free radicals present in the polymers are capable of initiating chemical reactions resulting in scission and cross-linking on irradiation. It may result in failure of material under application. The decomposition study has been carried out to predict the stability of developed materials under ionizing radiation conditions. The lifetime estimated for all developed material is found around 20 to 45 years at 50°C which is desired for a device under a nuclear environment. Accurate predictions are highly dependent on the testing methodology, the type and form of the composite used, and the processing history. Here we have discussed a thermal decomposition method to predict the life span of polymers.

Biography

Artical Title: Synthesis and utilization of bio-waste derived activated carbon for enhancement of tribological properties

Abstract

Critical climate change and environmental pollution not only demand the use of biodegradable material, but also the utilization of biowaste to convert them into value-added products. Bio-waste materials being natural materials are available in huge stock and are landfill materials. Dumping these bio wastes material in an open environment, provide a safe passage for bacteria growth, which in turn leads to bacterial disease. However, these waste materials could be of economic value when used in a sensible manner. The two such bio wastes eggshell and coconut shell were utilized. There two-fold application, one such application is using eggshell to convert into nanoparticles and other is two use these two in combination two produce activated carbon, which would further be utilized in the composite fabrication. In the present work the eggshell and coconut shell, synthesized activated carbon was utilized for fabrication of activated carbon epoxy composite. The attributes of activated carbon are identified through different characterization techniques (TEM, XRD, FTIR), The composites were studied for their hardness, moisture absorption and erosion wear behaviour at variable impingement angles (30°, 45°, 60°, and 90°) and impingement velocities (101 m/s, 119 m/s, and 148 m/s). It was observed that addition of activated carbon particles has enhanced hardness and wear resistance of the composite. Composite with 2 wt% particulate reinforcement was found to be the optimum percentage of reinforcement which was subjected to 82.4% less material loss i.e., erosion rate at 45° impact angle compared to neat polymer. It may be concluded from observation of results that, the present work is indicative of potential application in automobile body parts, pipelines carrying solid particulate matter etc.

Biography

Artical Title: Magnetic nanoparticles on drug delivery applications

Abstract

Nanotechnology, as a promising technique, has succeeded in overcoming a wide variety of technological impasses in unprecedented ways. Surprisingly, the convergence of nanotechnology and biology has provided a powerful impetus for research in a new area known as nanobiotechnology. In order to realize the potential of nanobiotechnology in the form of different functional agents for biomedical applications, nanoscale particles have been considered a significant class of biomaterials. The perfect concept of simultaneous therapeutic and diagnostic applications have been made feasible on a single so-called "theragnostic" agent by using the special properties of nanoparticles. Magnetic nanoparticles (MNPs) have drawn a lot of interest as a possible theragnostic device. Magnetic nanoparticles have been used as contrast agents in MRI, gene transfection, gene consignment, and to bind cytotoxic drugs for selective drug delivery for the past few years. The magneto-structural properties of the magnetic particle are critical for biotechnological applications. Because of the nanoscale size, the nanoparticle can quickly pass through thin veins and enter the cellular membrane. The particle's ferromagnetic and superparamagnetic properties allow it to be tampered by an external magnetic field and directed to the defined goal. The modified superparamagnetic nanoparticles' surface has hydrophilic functionalized groups that help with drug binding and biocompatibility. The poor retentivity of superparamagnetic nanoparticles when the applied external magnetic field is eliminated is a significant aspect. Furthermore, nanoparticles' capacity to monitor their size ranging from a few nanometres to hundreds of nanometres enables them to be similar to a biological organism of interest. Due to their peculiar properties of being biodegradable and biocompatible, superparamagnetic iron oxide nanoparticles (SPION) have gotten a lot of attention as scaffolds for constructing theragnostic agents. The present study discusses on the potential application of solvothermal synthesized magnetic nanoparticles for stimuli based drug delivery.

Biography

Artical Title: Variation in magnetic properties of CRNO AISI M-43 grade electrical steel post laser and TIG welding

Abstract

A cold rolled non-oriented (CRNO) electrical steel of M-43 grade is widely used in medium capacity rotating electrical systems and domestic appliances are investigated for observing the variation in magnetic property and losses, post TIG and laser welding. The investigation is made on the toroidal core samples welded on 6 sides around the outer periphery using TIG and laser welding. The welded toroidal core samples are observed for estimating the variation in magnetic properties and power loss density at different ranges of magnetic flux density. Additionally, the grain size analysis and micro-hardness testing of the weld samples is performed. Significant increase in losses is observed for TIG welded M-43 grade samples. The microstructural investigation also revealed the existence of relatively coarse grains in the weld region of TIG welded samples as compared to the laser welded samples. The maximum increase in hardness of around 62.3 HV as compared to the base metal is observed for the TIG welded samples. The B-H curve obtained for M-43 grade TIG welded, laser welded and non-welded samples. The hysteresis losses are found to be increasing as a result of internal stresses generated due to the welding process. It is evident that the laser welded samples revealed much controlled grain size variation as compared to TIG welded.The etched samples are observed under Scanning electron microscope (SEM), the laser welded sample with polygonal shaped ferritic grains. The maximum grain size of 52.1 µm is at the base metal (BM) region. However, coarse sized grains of maximum size 120.8 µm is at Heat Affected Zone (HAZ) region and 187.5 µm in the Fusion Zone (FZ) for TIG. The grain size measurements are performed using the Image J software.

Biography

Artical Title: Designing high efficiency materials for energy generation and storage

Abstract

Designing new materials with high efficiencies based on earth abundant nontoxic materials for renewable energy technologies is key to mitigate the climate change and develop prosperous sustainable society. With this idea in mind we are designing new materials useful for hydrogen economy, Li and Na ion battery cathodes, photovoltaic and thermoelectric applications using state-of-the-art density functional methods. Li-rich materials with simultaneous anionic and cationic reduction is one among the most promising class of cathode materials for high‐capacity Li-ion batteries. The recent studies on the Li-rich Li5FeO4 with defect antifluorite-type structure show that Li5FeO4 can enable high capacity by simultaneous reduction of Fe and oxygen atom without any obvious release of oxygen gas. In the present study we have substituted Fe site with Ti in different concentrations (Li5TixFe1-xO4 with x = 0.125, 0.250, 0.375, 0.500, 0.625, 0.750, 1.00) and investigated the structural, electronic and Li-diffusion properties using density functional theory calculations. The polyanionic compound Na2MnSiO4 is regarded as one of the promising cathode materials for Na-ion batteries due to good specific capacity along with its attractive prospect of utilization of two electrons in the redox processes. So, in this study we have performed the thermodynnamic and electronic structure analysis of Na2MnSiO4 using first principles density functional theory calculations. The intermediate ground state configurations for Na2MnSiO4 during Na de-intercalation were found using the cluster expansion method and are used to obtain the 0 K voltage profile as a function of Na concentration. This material shows an average voltage of 4.2 V and the finite temperature analysis at 300 K using Monte Carlo simulations indicates that this material undergo two phase mixing when desodiate beyond 1.5 Na/f.u. The involvement of oxygen in the redox reaction apart from the transition metal is identified using the Bader charge analysis. Relevant Na diffusion pathways and their corresponding calculated energy barriers are compared with the partially Fe substituted Na2MnSiO4 to understand the effect of Mn-site substitution on the process of Na migration through this material Compared with the remarkable achievement of using perovskites in photovoltaic applications, the role of antiperovskites in solar cells has not been adequately identified and reported. So we have predicted the crystal structures of the antiperovskites Be3PN, Mg3PN, Ca3PN, Sr3PN, Ba3PN and Zn3PN using structural optimization with stress as well as force minimization by considering 32 potential structural variants into the calculation. We found that all these compounds are having direct bandgap behavior with low carrier effective mass, high optical absorption, well separated electron-hole pair etc. Due to the iso-structural as well as isoelectronic nature of these materials with tunable bandgap value apart from the above mentioned other advantageous optoelectronic properties suggest that these materials are suitable for higher efficiency tandem solar cell applications. Multinary aliovalent substituted semiconducting half Heusler alloys are expected to have low thermal conductivity due to increase in the phonon scattering centers and thus it is expected to increase the thermoelectric figure of merit. So we have studied electronic structure, lattice dynamics, and thermoelectric (TE) transport properties of a new family of pentanary substituted TiNiSn systems using the 18 valence electron count (VEC) rule. The substitution of atoms with different mass creates more phonon scattering centers and hence lower the lattice thermal conductivity. The calculated lattice thermal conductivity for Hf containing systems La0.25Hf0.5V0.25NiSn and non Hf containing system La0.25Zr0.5V0.25NiSn are found to be 0.2 and 0.36 W/m-K, respectively and they can attain maximum ZT value of 0.78 at 500 K and 0.76 at 450 K, respectively. Based on the calculated results we conclude that one can design high efficiency thermoelectric materials by considering 18 VEC rule with aliovalent substitution. In order to identify potential materials for hydrogen storage application worldwide attention has been focused on hydrides with high gravimetric and volumetric capacity to have sustainable energy system. If one can find hydrogen storage materials where hydrogen is present in both negative and positive oxidation state within the same structural frame work then one can accommodate hydrogen with high volume density because of the attractive interaction between oppositely charged hydrogen. So, it is fundamentally as well as technologically important to identify compounds in which hydrogen is in amphoteric nature and understand the necessary criteria for its origin. We have identified several hydrogen storage materials with hydrogen in amphoteric state using van der Waals interactions corrected density functional calculations and explain such behaviour.

Biography

Artical Title: Device design optimization of highly efficient perovskite solar cell

Abstract

In order to provide experimental guidance, a theoretical study was performed on transparent conduction oxide (FTO)/TiO2/interface defect layer 1/CH3NH3SnI3/interface defect layer 2/Cu2O/ back contact solar cell. The simulation was performed under the illumination of 1000 W/m2, at 300 K and an air mass of AM 1.5G. The diffusion lengths of electron and hole were set to 260 nm and 560 nm in absorber layer, respectively. The set value is very near to recently observed experimental values. The device performance is severely influenced by the thickness of absorber layer, acceptor density, defect density and work function of various back contact electrode materials. Oxidation of Sn2+ into Sn4+ was considered and it is found that the reduction of acceptor concentration of absorber layer significantly improves the device performance. Further, optimizing the defect density (1014 cm−3) of the perovskite absorber layer, encouraging results of the Jsc of 40.14 mA/cm2, Voc of 0.93 V, FF of 75.78% and PCE of 28.39% were achieved. This theoretical simulation provides an appropriate direction for devolving photovoltaic technology.

Biography

Artical Title: Phytofabrication of silver and cupric oxide nanoparticles using Simarouba glauca and Celastrus paniculatus extracts and their enhanced apoptotic inducing and anticancer effects

Abstract

Objectives and scope : Silver (AgNPs) and Cupric oxide nanoparticles (CuONPs) were phytofabricated utilizing leaf extract of Simarouba glauca (SG) and aerial extract of Celastrus paniculatus (CP) to evaluate anticancer effect and also to verify the apoptosis, cell cycle analysis. Methods used: free radical scavenging assays like DPPH, ABTS and NO; MTT assay, flow cytometry and caspase-3; EAC model with biochemical and haematological parameters. Results and discussions: Characterization was validated using FTIR, SEM-EDX, TEM, XRD and UV-Vis analysis. The green synthesized AgNPs and CuONPs showed potent antioxidant potential with IC50 value of about 34.01+0.64 µg/mL contrasted to ascorbic acid. The anticancer activities on cancerous cell lines like MCF-7 and HT-29 cell lines revealed that AgNPs and CuONPs synthesized using S. glauca and C. paniculatus indicated IC50 values ranging from 70.85+0.67 to 240.6+0.57 µg/mL. They could not effectively prohibit the growth of immortalized normal human breast epithelial cell lines (MCF-10A). To be more precise for anticancerous effect, molecular mechanism was examined in MCF-7 cell line treated with CuO-CP NPs by cell cycle analysis that depicted 75.28 % of cell arrest in Sub G0/G1 phase and 71.29 % of cells were gated in late apoptotic phase of Annexin V and propidium iodide (PI) compared to control cells. The cytotoxicity induced by apoptosis was further confirmed by fluorescent images. The synthesized nanoparticles also demonstrated less hemolysis efficiency and are evidenced by SEM images. We have also evaluated the in vivo antitumor efficacy of CuO-CP NPs treated against Ehrlich ascites carcinoma (EAC) bearing C57 mice for the first time and examined by variations in growth parameters, biochemical assays (like lactoperoxidase, reduced glutathione and myeloperoxidase), hematological profile, and histopathological analysis in comparison with control. Conclusion: The green synthesized nanoparticles exhibited effective control of cancer cells in both in vitro and in vivo laboratory conditions and thus can be evaluated for lead compound and scale up for industrial usage.

Biography

Artical Title: Air-stable and high mobility based electron transport semiconducting material hexachloro- hexa-azatrinaphthylene

Abstract

In the last few years, organic semiconductors (OSCs) have attracted a considerable amount of attention due to their wide potential applications in various electronic devices such as organic field-effect transistors (OFETs), organic photovoltaic devices (OPVs), organic light- emitting diodes (OLEDs), and organic solar cells (OSCs). Unlike their inorganic counterparts, organic semiconducting materials are cost-effective, lightweight, and flexible and provide the versatility of chemical synthesis. However, one of the major challenges for the development and fabrications of organic semiconductors for industrial applications is their air instabilities. From the theoretical point of view, the air-stability of the organic semiconducting material depends upon its low-lying frontier molecular orbitals and the energy gap in between them. A new n-type organic semiconductor based on the haxachloro-hexaaza-trinaphthylene compound is reported. The electronic structure and charge transport properties of the compound is calculated in the framework of density functional theory (DFT). The electron- withdrawing group (-Cl) on the end position of the compound could help to lower the LUMO energy level and improve the air-stability and charge carrier mobility. The large electron affinity (2.60 eV) and low LUMO energy (-3.63 eV) suggests that the compounds were to be air-stable and N-type organic semiconductor. Moreover, lower values of the electron- injection barrier as compared to those of the hole-injection barrier implied that the investigated compounds were basically N-type semiconductors. The computed electronic coupling of LUMO of the compound was found to be comparatively larger in the transverse- channel (86.6 meV) than other channels. The computed large electron and hole mobility was found to be 3.54 cm2V-1s-1 and 0.014 cm2V-1s-1. Further, Hirshfeld analysis depicting the distribution of surface charge in between the molecular layers of the crystals revealed that the principal interactions were mostly due to the Cl…H/H…Cl and Cl…Cl contacts of the compounds.

Biography

Artical Title: Controlling non-equilibrium processes for fractal growth

Abstract

Fractal structures are commonly found in nature. This work demonstrates the growth of tin oxide (SnO2) fractals on large-area glass substrate. Growth of fractals with fractal dimensions varying from 1.52 to 1.86 were successfully grown. The shape of fractals changed from rhombohedra to fern-like to sword-shaped fractals. The flux, temperature and pH of the solution is understood to play an influential role in the final shape of the fractals. The fractal structures have significant surface roughness and therefore have many adsorption sites. These sites are interconnected by the inherent nature of fractals and therefore may exhibit better charge transport properties. The experiments are underway to optimize the charge transport observed in fractals and investigate their gas sensing response. A better understanding of the growth of fractals may lead to better predictions of material failure in fields like lithium-ion batteries or in alloy formation. Better properties may also lead to applications in gas sensing, potential SERS-substrates, wound healing phenomenon, etc. Thus, growth of fractal structures and a control over their morphology is the fundamental step to be addressed. The present work is an effort in this direction.

Biography

Artical Title: A novel fabrication of superhydrophobic surfaces on aluminium substrate by picosecond pulsed laser

Abstract

Superhydrophobic surfaces have emerged because of their unique properties like corrosion resistance, self-cleaning, anti-icing and being anti-bacterial. A simplistic and highly effective ultra-fast laser technology was used to fabricate superhydrophobic surface on aluminum substrate. Compared to other laser systems, picosecond laser systems have smaller thermal affected area on the aluminum substrate. They also offer high efficiency, not as much of waste materials and cover enormous areas for mass production. Tilted groove patterns of various angles with respect to horizontal were textured on the substrate by using picosecond laser pulses. The laser parameters, such as hatching distance (HD) and scanning speed (SS), can be varied by keeping the laser power as constant for the various tilted angle of the groove pattern. The textured surfaces were initially super hydrophilic when kept in polyethylene zip lock cover and which also exhibits super hydrophobicity of maximum 155.5° when observed after 15 days. The morphology of surface was characterized by scanning electron microscope, EDX and X-ray diffraction.

Biography

Artical Title: Effect of Ar+ ion implantation to enhance non-linear optical property on the L-Proline-doped Potassium hydrogen phthalate single crystals

Abstract

Single crystals of semiorganic potassium hydrogen phthalate crystals and L-Proline amino acid doped potassium hydrogen phthalate crystals were implemented with 10KeV Aa ions at various fluencies of 1 x 1015 5 x 1015, 1 x 1016 and 5 x 106 ions / cm2 to enhance their nonlinear optical property. The study reveals that Ar ion irradiation indicated the role of defects which could have influenced the non linear optical behavior.

Biography

Artical Title: Photoconductive laser spectroscopy and sub-bandgap defects in the metal-oxide semiconductors

Abstract

The emergence of high performance large-area electronic materials enabled the display technologies, which have transformed the way people interact with mobile devices such as smartphones and tablets. The most promising family of materials for this application are the metal-oxide semiconductors (MOS). Properties, which make MOS desirable, include their optical transparency, bandgap modulation, and high electron mobility. The journey from lab curiosity to market for MOS has taken place in a short time span, and current applications of the technology include flat panel displays, sensors, and logic devices. One of the chief problems of MOS is the tendency to form sub-bandgap defects, which can have a detrimental effect on device performance. Gaining an in-depth understanding of the behavior of these sub-bandgap defects will be key to unlocking better device performance or perhaps even discovering beneficial applications for sub-bandgap defects. We developed an alternative spectroscopic technique, the photoconductive laser spectroscopy that is able to identify distinct spectral signatures of sub-bandgap defects in MOS used in thinfilm transistors (TFTs). These sub-bandgap peaks are not normally visible in previously reported spectra measured by using available spectroscopic techniques. Negative bias illumination stress (NBIS) has a strong effect on the stability of the TFT performance. It is assumed that during NBIS, the deep neutral sub-bandgap defects in the MOS activated and modulate the threshold voltage of the TFT. I will talk about the photoconductive laser spectroscopy technique, which we developed, its sensitivity and effectiveness to identify and study, the modulation of sub-bandgap defects in the metal-oxide semiconductors.

Biography

Artical Title: Sensing film materials development for FET-based pH sensors

Abstract

Ion-Sensitive Field-Effect-Transistor (ISFET)-based chemical/biochemical sensors are used for measuring ion concentrations analyte solutions. Most commonly, they are used as pH sensors, where the current through the transistor changes with respect to the ion concentration at the sensing region (gate). ISFET is a solid-state device, which makes it rugged for the measurement of ion activities in analytes, with the aid of a reference electrode and it has been widely used for pH measurements. PH is one of the most important parameters in agricultural, environmental, bio-medical and potable water studies. ISFET has attracted much interest due to the feasibility of facile integration with readout circuits. It is an alternative to the conventional glass membrane electrode-based pH sensors, where it enables measurements in ultra-small volumes with fast response. This work deals with the design, modelling, fabrication and characterization of ISFET-based pH sensors. The most critical element in ISFET-based pH sensors is the sensing film deposited over the gate region of the sensor. In this work, the sensing films are deposited using pulsed-DC magnetron-assisted reactive sputtering technique. Various process parameters for deposition of the film were optimized through several experiments. The deposition process for three sensing films were optimized, namely, AlN, Al2O3 and TiN, and their material characterization was carried out using various techniques. ISFET-based pH sensors were fabricated using well established, CMOS compatible unit processes. In this work, three variants of ISFET-based pH sensors have been fabricated with AlN, Al2O3 and TiN as the sensing films, using self-aligned process. The devices were encapsulated using the Dam-and-Fill technique and packaged using thick-film alumina technology. The sensors were characterized for pH sensing applications. Moreover, drift and hysteresis studies were performed for each sensor and low drift and hysteresis values were obtained for the fabricated ISFETs.

Biography

Artical Title: Maximum power point in a single step in solar photovoltaic panels

Abstract

Solar PV system arises as viable option in the critical power system era, its low efficiency energy conversion attribute necessitates an efficient power conversion system. The nonlinearity of I–V (current–voltage) characteristic and its alteration for an assorted insolation and temperature values may enable the alteration in terminal voltage. This may deviate maximum power point due to which the available maximum power delivery to load can be differed. Literature of this field reiterated that the uniform insolation and partial shading condition demands undeniable need of maximum power point tracking. Nonetheless through investigation in this direction furnishes the availability of a bunch of such techniques; each of them possesses its own pros and cons. This ubiquitous trait of available maximum power point tracking (MPPT) techniques unfolds the complexity in its precise selection. To diminish such complexity this article offers a novel idea in DC-DC converter hardware alteration instead of software (algorithm) to reach maximum point in a single step. A high precise capacitor with low electro static resistance is connected in parallel with a DC-DC converter (any type) with a single semi-conductor switch. This arrangement enables user to know the entire curve region with maximum operating point, thanks to highspeed microcontrollers. The converter is then in turn to operate accurately at that particular point, which removes the oscillation around MPP point. A hardware prototype of 1 kW lab scale setup has been developed and experimental results shows 18% improvement in MPP tracking capability (which generates 18% more energy than exist), which we see as a game changer for PV industry. The detailed circuit, and its economic analysis will be given in the full-length article.

Biography

Artical Title: Materials for non-conventional solar cells developing cost effective sustainable green energy

Abstract

Solar power is the key to a clean energy future. The sun provides more than enough energy to meet the whole world’s energy needs, and unlike fossil fuels, it won’t run out anytime soon. That’s why we’re investing heavily in solar plants and why we are now offering solar kits to the society. Solar panels produce electricity by transforming the continuous flow of energy from the sun to electricity. As a renewable CO2-free power source, the environmental impact of solar power is significantly smaller than other power generation methods. The photovoltaic process that transforms sunlight into electricity doesn’t require any fuel and has no variable costs. Silicon is, by far, the most common semiconductor material used in solar cells, representing approximately 95% of the modules sold today. As a renewable energy source, the only limitation of solar power is our ability to turn it into electricity in an efficient and cost-effective way. With a higher efficiency, fewer panels, or modules, need to be installed to reach a desired power target. This means less labor, less land and less hardware. That game changed a couple decades ago with the advent of thin-film solar cells and other cost-effective solar cells that forced the industry to focus on lower costs rather than high performance. Now that solar cells are less expensive to manufacture, the industry has entered a third phase with the goal: increasing efficiency while keeping low-cost manufacturing. A several such solar cells will be discussed during the presentation.

Biography

Artical Title: Artificial intelligence techniques in Healthcare: Opportunities and challenges

Abstract

Artificial intelligence (AI) is gradually changing medical practice. With recent progress in digitized data acquisition, machine learning, and computing infrastructure, AI applications are expanding into areas previously thought to be only the province of human experts. We summarize the latest developments of applications of AI in biomedicine, including disease diagnostics, living assistance, biomedical information processing, and biomedical research. This talk aims to keep track of new scientific accomplishments, understand the availability of technologies, and appreciate the tremendous potential of AI in biomedicine. It can be asserted that the application of AI in biomedicine is still in its early stage, just like AI itself. New progress and breakthroughs will continue to push the frontier and widen the scope of AI applications, and fast developments are envisioned soon. This talk aims to: • Outline recent breakthroughs in AI technologies and their biomedical applications • Identify the challenges for further progress in medical AI systems • Summarize AI's implications in healthcare.

Biography

Artical Title: Flying robot path planning techniques and its trends

Abstract

A Flying robot is a system capable of vertical take-off and landing to perform some specific task with no direct human intervention. Flying robots are distinct from other robots by their ability to fly with no direct human control and are capable of making a decision based on the situation. Drones, Aerial robots, Unmanned Aerial Vehicles (UAV) are few examples of flying robots. Path determination of flying robots is one of the most critical aspects of robot Routing design. Path planning is a technique which tells flying robot how to fly, where to fly and to find a collision-free optimal path. Numerous techniques have been put forward over the past few years to find an optimal path for flying robots. This work discusses on new trends led by artificial intelligence and safe human-robot interaction for optimal path planning of aerial robots. Furthermore, a comprehensive study is carried out on various 2D and 3D path planning algorithms done to date and different algorithms are classified based on important criteria for optimal path planning for flying robots.

Biography

Artical Title: Effective sensitization of Yb3+ ions on Yb3+ or Nd3+ co-doped fluoroborate glasses for NIR luminescence applications

Abstract

Nd3+/Yb3+ co-doped fluoroborate glass samples were fabricated by melt quenching. The infrared luminescence of the Nd3+/Yb3+ codoped fluoroborate glass was characterized by XRD, SEM, FT-IR, optical Absorption, Photoluminescence and time resolved luminescence. There is an effective mutual energy transfer process between Nd3+ and Yb3+ in prepared glasses was observed. Excitation was made using a laser diode tuned to 808 nm wavelength. The broad emission range from 850 to 1400 nm is due to both Nd3+ (4F3/2→4I9/2, 4F3/2→4I11/2 and 4F3/2→ 4I13/2) and Yb3+ (2F5/2→2F7/2) transitions. The dependence of NIR emission, lifetime, and the energy transfer efficiency (ηETE) with the concentration of Yb3+ was studied in detail. The Photoluminescence spectra along with donor decay curves have been used to establish the energy transfer mechanism between Nd3+/Yb3+ ions. The results represents that the sensitization of Yb3+ is possible through 4f-4f transition of Nd3+ ions in prepared glasses. The photoluminescence properties of the Nd3+ singly doped and Nd3+/Yb3+ co-doped prepared glasses indicate their suitability as multiple pump channel sources for Yb3+ fiber laser systems. Those results prove that Nd3+/Yb3+ codoped prepared fluoroborate glass is the potential infrared laser gain material.

Biography

Artical Title: Effect of isothermal aging at 750℃ on microstructure and mechanical properties of UNS S32101 lean duplex stainless steel

Abstract

UNS S32101 lean duplex stainless steel (LDSS) is utilized in the present investigation which has a two-phase microstructure consisting of austenite () and ferrite () in near equal proportions. Aging at high temperature results in formation of  phase reducing ductility and also corresponding depletion of Cr from the adjoining matrix. The effect of long-term aging on the microstructure and mechanical properties is still an active area of research for lean DSSs. In the present work effect of aging at 750°C (up to 480 h) on microstructure and mechanical properties has been systematically studied. Scanning electron microscopy (SEM) revealed that the precipitates were distributed along ferrite/austenite (/γ) interfaces and ferrite/ferrite (/) boundaries. Nitrides (mainly Cr2N) were observed in initial phases of aging and σ phase afterwards, mostly at longer aging times. The decrease of Ni and Mo and increase in N in UNS S32101 steel delayed the precipitation of σ, but could not avoid it completely. The room temperature absorbed impact energy of specimens decreased gradually as the aging time increased. The lowest value of absorbed impact energy was found to be 24±2 J after 480 hours of aging, which was only ~11% as that of solution annealed specimen. Fractography also showed that the fracture morphology changed from fibrous (ductile) to dominant brittle (which involved predominance of cleavage facets along with long, wide cracks i.e., delamination fracture) with increasing aging time. Tensile tests also showed a decrease in ductility and an increase in yield stress/ultimate tensile strength with aging time.

Biography

Artical Title: Highly sensitive photonic crystal fiber on hybrid layer of metal or 2D materials

Abstract

Platinum Diselenide, PtSe2 is gaining popularity due to its intriguing optoelectronic, thermoelectric, and semiconductor properties. They are non-toxic, chemically inert, and allow for high biomolecule absorption, making them ideal for use in sensors to improve sensing. Here, we proposed Photonic Crystal Fiber (PCF) based Surface Plasmon Resonance (SPR) sensor for enhanced refractive index sensing at mid infrared wavelengths. To achieve this, Tri-Path PCF (TP-PCF) was coated with a gold/PtSe2 hybrid layer, which allows light to freely pass through the cladding and interact with the plasmonic material, resulting in a significant coupling effect. Finite Element Method is used for numerical examination and exhibits maximum wavelength sensitivity of 42,000 nm/RIU and maximum wavelength resolution of 2.4 x 10-6 within the analyte range from 1.33 to 1.38, which almost covers the unknown analytes of chemical and bio.

Biography

Artical Title: Environmental pollution cleaning using organic smart material by photocatalysis

Abstract

Complex aromatic organic dyes and pigments are the vital waste which damages the human health as well as aquatic life. Researchers are working to overcome this serious issue from many years, but to developed cost-effective and eco-friendly method is unsolved challenge. Of late, inorganic based photocatalysis helps to treat industrial wastewater up to some extent. Various inorganic semiconductor photocatalysts with high efficiency have been reported with different dyes degradation study. We have synthesized PQ an intermediate require synthesizing Pentacene which is well known organic semiconductor from last couple of decades. After complete characterization using spectroscopic and microscopic techniques, we explored PQ for Industrial Dye degradation and Photocatalytical H2S splitting for the first time. We also synthesized composite system of PQ-TiO2 with inorganic semiconductor photocatalyst. Recently a report of PQ-MoS2 photocatalyst also covers the water splitting area. This organic PQ photocatalyst have high potential in photocatalysis field which can be utilized for the clean environment and for water treatment.

Biography

Artical Title: Greener synthesis of zirconia nanoparticles and their applications

Abstract

Zirconia in nanoscale has been found useful as nanocatalyst, nanosensor, nano adsorbent. Additionally, its biomedical applications in dentistry and drug delivery, and interesting biological properties such as anti-microbial, anti-oxidant, and anti-cancer activity have further motivated the researchers to explore different synthetic pathways. In this work, greener synthesis of zirconia nanoparticles was carried out suing using green tea leaves and zirconium oxychloride. The prepared nanoparticles were characterized with UV-visible spectroscopy, transmission electron microscopy and powder XRD, and scanning electron microscopy. Powder XRD pattern and microscopic studies confirm the formation of nanocrystalline material having the size in the range of 15-40 nm. Keeping in view biomedical applications of zirconia, antibacterial and antifungal activities of prepared nanoparticles were investigated. These studies have shown promising results.

Biography

Artical Title: Seasonal variation of manakudy estuarine water chemistry, south west coast of India

Abstract

Toxic trace elements from rivers are either weathered naturally from soils and rocks or introduced anthropogenic from point or non-point sources, in labile or particle form, to be debouched into the sea through estuaries. The chemistry and ecology of an estuary system differ significantly from those of a fluvial or marine one. Twenty water samples were collected around the Manakudy estuary and examined throughout the pre and post monsoon seasons. To acquire a better knowledge of the geochemical behaviour of physico-chemical parameters, main ions, and trace elements, as well as variations in associated chemical fluxes. With respect to the mean values during both monsoons, the principal ion sequence of abundance is Na>Mg>K>Ca>NO3>SiO4>P>NO2. When compared to Cu, Cr, Cd, and Co, the mean concentrations of Fe, Zn, Mn, and Pb are 4128, 42, 36, and 5.18g/l in premonsoon and 2064, 31, 37, 25, and 6.17g/l in postmonsoon, respectively. The contamination factor (CF) and potential ecological risk index (PERI) were used to calculate the toxicity level of trace metals in water. Based on CF values, Cu was found to be the most polluting metal in estuary water. Premonsoon water has a moderate to high danger, whereas postmonsoon water has a moderate to significantly high risk. The interconnected components of water quality attributes that influence the estuarine water environment include physico-chemical parameters, main ions, and trace elements. As a result of geogenic and anthropogenic processes enriching and overloading these components, species diversity, metabolism, and habitat population are negatively impacted. To reduce the overloading of contaminants in the Manakudy estuary water, strategic management plans should be established.

Biography

Artical Title: Heart disease prediction and detection using association rule ming techniques

Abstract

Data science mining methods are utilized in the field of medication for different purposes. Mining affiliation rule is one of the intriguing points in information mining which is utilized to produce continuous itemsets. It was first proposed for market bushel examination. Analysts proposed varieties in methods to create incessant itemsets. Creating huge number of incessant itemsets is a tedious cycle. In this paper, the creators contrived a strategy to anticipate the danger level of the patients having coronary illness through incessant itemsets. The dataset of different coronary illness patients is utilized for this exploration work. The information mining strategies-based frameworks could vitally affect the workers' way of life to anticipate heart sicknesses. There are numerous logical papers, which utilize the strategies of information mining to anticipate heart infections. Nonetheless, restricted logical papers have tended to the four cross-approval methods of dividing the informational index that assumes a significant part in choosing the best procedure for foreseeing coronary illness. Pick the ideal blend between the cross-approval methods and the information mining, order strategies that can upgrade the exhibition of the forecast models. This paper means to apply the four-cross-approval methods (holdout, k-overlay cross approval, separated k overlap cross-approval, and rehashed irregular) with the proposed techniques Extended Support Vector Machine and Extended KNN to work on the precision of coronary illness expectation and select the best forecast models. It investigates these procedures on a little and huge dataset gathered from various information sources like Kaggle and the UCI AI archive. The assessment measurements like exactness, accuracy, review, and F-measure were utilized to quantify the presentation of forecast models. Experimentation is performed on two datasets, and the outcomes show that when the dataset is epic (50000 records), the ideal mix that accomplishes the most noteworthy precision is holdout cross-approval with the neural organization with an exactness of 71.82%. Simultaneously, Repeated Random with Random Forest considers the ideal blend in a little dataset (303 records) with a precision of 89.01%. The best models will be prescribed to the doctors in business associations to help them anticipating coronary illness in workers into one of two classifications, cardiovascular and non-heart, at a beginning phase. Successive itemsets are produced dependent on the picked indications and least help esteem. The separated successive itemsets assist the clinical professional with settling on indicative choices and decide the danger level of patients at a beginning phase. The proposed strategy can be applied to any clinical dataset to anticipate the danger factors with hazard level of the patients dependent on picked factors. An exploratory outcome shows that the created technique distinguishes the danger level of patients effectively from continuous itemsets. The early recognition of heart illnesses in representatives will further develop efficiency in the business association

Biography

Artical Title: Amelioration of structurally disturbed soil through microbe-manure amalgams

Abstract

Less precipitation, high temperature, and minimal natural vegetation are characteristic of regions having arid climate. The harsh environment massively destructs the soil structure of that area by burning soil organic carbon, leading to deteriorated soil nutritional quality, creating a huge threat to agricultural production and food security. Direct application of organic wastes not only substitutes lost organic carbon but also restores soil structure and fertility. Organic amendments i.e., farm manure (FM), poultry manure (PM), molasses (MO) and Exo-Poly Saccharides (EPS) producing rhizobacterial strains i.e., M2, M19, M22 amalgams were used as treatments. To assess the impact of treatments on soil carbon and structure restoration to hold more water and nutrients, a 42-day incubation experiment using completely randomized design (CRD) under the two-factor factorial arrangement was conducted. Macroaggregation (0.25 to >1 mm), carbon retention in macroaggregates, active carbon (dissolved organic carbon, a mineral associated organic carbon, microbial biomass carbon), total organic carbon, the carbon mineralization activities, and water retention capacities were observed highest in soils that were treated with (FM+M2, FM+M22, PM+M19, and MO+M19). Finally concluded that organics mineralization by microbial actions release organic glues that not only imparts particle aggregation but also conserve organics as aggregate entrapped carbon. Amalgamated application of microbe-manure combinations directly impacts soil structure and organic carbon contents, but in an indirect scenario it improves fertility and productivity of soil.

Biography

Artical Title: Chloroform-Injection (CI) and Spontaneous-Phase-Transition (SPT) are novel methods, simplifying the fabrication of liposomes with versatile solution to cholesterol content and size distribution

Abstract

Intricate formulation methods and/or the use of sophisticated equipment limit the prevalence of liposomal dosage-forms. Simple techniques are developed to assemble amphiphiles into globular lamellae while transiting from the immiscible organic to the aqueous phase. Various parameters are optimized by injecting chloroform solution of amphiphiles into the aqueous phase and subsequent removal of the organic phase. Further simplification is achieved by reorienting amphiphiles through a spontaneous phase transition in a swirling biphasic system during evaporation of the organic phase under vacuum. Although the chloroform injection yields smaller Z-average and poly-dispersity-index the spontaneous phase transition method overrides simplicity and productivity. The increasing solid/solvent ratios results in higher Z-average and broader poly-dispersity-index of liposomes under a given set of experimental conditions, and vice versa. Surface charge dependent large unilamellar vesicles with a narrow distribution have poly-dispersity-index < 0.4 in 10 µM saline. As small and monodisperse liposomes are prerequisites in targeted drug delivery strategies, hence the desired Z-average < 200 d.nm and poly-dispersity-index < 0.15 is obtained through the serial membrane-filtration method. Phosphatidylcholine/water 4 µmol/mL is achieved at a temperature of 10◦C below the phase-transition temperature of phospholipids, ensuring suitability for thermolabile entities and high entrapment efficiency. Both methods furnish the de-novo rearrangement of amphiphiles into globular lamellae, aiding in the larger entrapped volume. The immiscible organic phase benefits from its faster and complete removal from the final product. High cholesterol content (55.6 mol%) imparts stability in primary hydration medium at 5 ± 3 ◦C for 6 months in light-protected type-1 glass vials. Collectively, the reported methods are novel, scalable and time-efficient, yielding high productivity in simple equipment.

Biography

Artical Title: Internet of things and cloud computing survey

Abstract

Internet of things and cloud computing play a vital role in the area of Information Technology now adays. Both of these technologies are essential for the upcoming developments and research in computing domain. This paper will rectify a survey of both these technologies playing a vital role so far. Some observations and comparisons are notified here for the information and verification.

Biography

Artical Title: Fabrication of organic semiconductor based humidity sensor and its environmental applications

Abstract

The compound lophine, 2, 4, 5-triphenyl-1H-imidazole, has been used to fabricate humidity sensors. The sensors were tested in different humidity environments, and at various applied frequencies. The SEM images showed inter-woven spiky needles, pores, pore-channels of diverse shapes and sizes. The H2O molecules interacted with N and NH sites in the aromatic ring of the compound and thus altered the electrical properties due to the imidazole scaffold’s electron acceptor and trifling donating nature. The conduction mechanism is based on Grotthuss hydroxide transfer and prototropic mobility. The calculated dielectric constant of the material was 1.69. In 45-95 %RH limit, the devices capacitance was increased from 11 pF to 460 pF and 7.29 pF to 18.9 pF at applied frequencies 1 kHz and 10 kHz, respectively. The response/recovery time was 39/20 seconds, respectively. The maximum hysteresis was 0.44 % (at 1 kHz) and 1.09 % (at 10 kHz). The R2 values (goodness of fit) 0.98 and 0.99 for chemisorbed and multi-layered physisorbed layers are close to unity and thus considered the best linear-fit. The sensors showed a strong affinity to moisture at ambient conditions with low hysteresis. Fabulous improvement in the device’s sensitivity has been noted over the reported sensitivity of devices based on ceramic materials.

Biography

Artical Title: Lead-free double perovskites for thermoelectric and optoelectronic applications: Ab initio study

Abstract

Energy consumption is increasing day by day in today’s world so it is the matter of concern for the scientific community to find the alternative power generation mechanisms by minimizing the whole world’s reliance on traditional power generation methods. Thermoelectricity and optoelectronics have emerged as an attractive area of research for finding efficient non-traditional power generation mechanisms. In this scenario, it is a matter of immense potential to find more efficient materials for optoelectronic and thermoelectric power generation. Currently, the structural, electronic, optical, phononic and thermoelectric properties of double perovskites A2NaBCl6 (A=Cs,Rb,K and B=Bi,Sb) have been studied in details using density functional theory (DFT) within the frame work of generalized gradient approximation(GGA). The results of Cs2NaBiCl6and Cs2NaSbCl6are consistent with already reported data whereas Rb2NaBiCl6, K2NaBiCl6, Rb2NaSbCl6 and K2NaSbCl6have been reported for the first time. The structural stability, thermal stability, large Seebeck coefficients and figure of merit (close to unity) of these lead-free double perovskites suggest various thermoelectric device applications. High absorption coefficient, high optical conductivity and low reflection coefficient suggests the applications of these compounds in solar cells as a source of low cost eco-friendly power generation schemes.

Biography

Artical Title: Contribution of carbon mesopores towards the improved performance of ionic liquid-based EDLCs at different temperatures

Abstract

During the presentation an important role of mesopores investigated in electric double-layer capacitors (EDLCs) operating from 24°C down to−40°C by using carbons with hierarchical porosity will be discussed. Home-made carbons were prepared using different precursors as the carbon source, while a binary mixture of imidazolium-based fluorinated ionic liquids was used as a solvent-free electrolyte. It will be shown that short-range graphene layers produced with 8-nm silica nanoparticles lead to the creation of transport channels which better accommodate ions. We explain these findings per coulombic interactions among the ions and between the pore wall and the ionic species under confinement and electrochemical polarization conditions. Further, it will be shown that a microporous carbon performs better than hierarchical carbons at room temperature; however, owing to the large fraction of mesopores, the latter exhibit far higher capacitance down to−40°C. While the ordering of ions in confinement is more critical at room temperature and dictated by the micropores, low temperature performance of supercapacitors is determined by the mesopores that provide channels for facile ion movement and keep the bulk ionic liquid–like properties.

Biography

Artical Title: Dispersion of singled walled carbon nanotube in water in presence of direct current field

Abstract

The dispersed solution of Single-walled carbon nanotubes (SWCNT) have been utilized in different industrial and laboratory applications such as electrodes of batteries, super capacitors, gas sensors etc. There are many difficulties and challenges to make a stable suspension of SWCNT as they tend to self-associate into clusters. These clusters have to be dispersed before they could be used for different applications. In this research, an effort has been made to reduce the agglomeration of SWCNT by sonication in presence of Direct Current field (DC). It was found that sonication under DC field has increased the degree of dispersion. Furthermore, the result shows that SWCNT can be dispersed with or without use of any surfactants by sonication in presence of DC field. The use of surfactants could increase the impurity content of dispersed solution which was reduced by our modified method of dispersion. In addition, it is shown that our modified method can be used to study dispersion with minimal use of expensive chemicals like SWCNTs.

Biography

Artical Title: Kinetic study of removal of fluoride and nitrate, synthesis and characterization of layered double hydroxide

Abstract

Layered double hydroxides (LDH) are a class of naturally occurring and synthetic anionic clays classified under the hydrotalcite-like compound. Fluoride (F-) is an essential micronutrient for the calcification of bone and dental enamel formation. But excessive intake causes skeletal and dental fluorosis. The contamination of F in surface and groundwater could come either from natural geological sources and industrial wastewater. Nitrate (NO3-) is a widely spread groundwater contaminant. It causes severe health & environmental problems like blue baby syndrome and eutrophication. LDH can be synthesized by using the co-precipitation method. Magnesium dichloride hexahydrate (MgCl2.6H2O), Aluminium chloride hexahydrate (AlCl3.6H2O), Potassium Hydroxide ( KOH ), Potassium Carbonate ( K2CO3 ), Deionized water were used to synthesize LDH. It is a comparatively economically feasible synthesis method. The synthetic product can be identified by using the Powder X-ray Diffraction (PXRD) method by using the values at 7.5916(003), 3.8011(006), 3.1390(009) (JCPDS-22-700) and Fourier Transform Infrared Spectroscopy (FTIR) peaks at 558 cm-1(Mg-O stretching), 876 cm-1(Al-O stretching), 1411 cm-1 (C-O stretching), 3200- 3500 cm-1 (O-H stretching). LDH was stirred with F- and NO3-for 0 - 4 hours respectively. After each 10 minutes time interval, remaining anion concentrations were measured respectively. Finally, the best fitted kinetic model was found for each. Removal of fluoride has been successfully followed Pseudo second-order kinetic model and the kinetics of fluoride removal is not affected by initial concentration and amount of adsorbent quantity. The highest efficiency of removal of fluoride has been found with 4.00x103 mg L-1of LDH and the initial fluoride concentration was 10.00 mg L-1. Removal of nitrate has successfully followed the Pseudo 1st order kinetic model. The efficiency of F removal is 87.58%, while nitrate removal efficiency is 85.38%.

Biography