The Robert M. Buchan Department of Mining, Queenʼs University, Canada
Several hydrometallurgical methods have been proposed or tested for the processing of arsenic containing copper sulfide ores and concentrates. This paper reviews the metallurgy of primary copper sulfide ores and concentrates. An update on the recent developments of the chloride processing of sulfide ores and concentrates is presented.
The arsenic immobilization process used to remove arsenic from arsenic-containing streams depends on the arsenic concentration in the solution and the arsenic species present. Regardless of the method used to remove arsenic from solution, ideal is that the majority of arsenic be in pentavalent oxidation state, As(V). Most of the arsenic immobilization processes used in the industry are hydrometallurgical in nature; however, there are currently studies underway which use pyrometallurgical processes to oxidize and / or immobilize arsenic.
In this paper we have reviewed and critically compared several arsenic oxidation and immobilization methods. The arsenic immobilization options from the weak acid scrubbing solutions including: (1) lime precipitation, (2) sulfide precipitation, (3) arsenic co-precipitation with ferrihydrite, (4) atmospheric ferric arsenate precipitation, and (5) scorodite precipitation methods such as Dowa process and EcoMetales Process have been reviewed.
Finally, the preliminary techno-economic analysis of the selected arsenic immobilization of a solution with 15 g/L total As, with 60% As(III) and 40% As(V) were carried out.
Biography:
Ahmad has earned his PhD in Materials Engineering from The University of British Columbia, Vancouver, BC, Canada. Upon completing his PhD, Ahmad joined the Technology Centre of Barrick Gold Corp. in Vancouver, as an NSERC Industrial Research & Development (IRDF) Postdoctoral Fellow. He joined The Robert M. Buchan Department of Mining at Queenʼs University as an Assistant Professor of Hydrometallurgy and Environment in January 2014.
Assiut University, Egypt
The increase of computing power in recent years has made large scale simulation with million, or even billion of atoms is possible. Computer simulations using classical interatomic potentials are an efficient tool to study and understand materials properties and to investigate processes of materials on the atomic level. In this manner length and time scales can be considered which are often hardly accessible by experiments. In the talk two different applications of atomistic simulations are considered.
In the first topic the energetics and thermodynamics of the coherent copper nanoclusters in bcc-Fe are obtained using a combination of on-lattice Monte Carlo simulations and off-lattice molecular dynamics. These nanoclusters are assumed to be the main cause of hardening and embrittlement of Cu-bearing reactor pressure vessel steels since they act as obstacles to dislocation motion within the grains of the polycrystalline bcc-Fe.
The second topic about the fracture of ferrite steels (structural materials for nuclear fission reactors) during neutron irradiation in which the interaction between embedded nanocluster and an edge crack in the framework of linear elastic fracture mechanics (LEFM), are investigated at nanoscale using molecular static (MS) simulations.
1Politecnico di Torino, Dipartimento di Scienza Applicata e Tecnologia (DISAT), Italy
2Istituto Italiano di Tecnologia, Center for Sustainable Future Technologies, Italy
Internet of things and big data acquisition demand portable and compatible energy storage devices for retrieving and processing information. Supercapacitors being high power, high rate capable and long cyclic life energy devices are promising candidates among its commercial counterparts. Aforementioned, energy requests can be addressed by integrating fiber shaped flexible supercapacitors on to physical substrates and textiles. Therefore, current collectors must be flexible and should be configurable into complex devices such as pacemakers, artificial skins, foldable displays, wireless sensors and smart cards. In current study, we report the two-steps electro deposition of stoichiometric MnO2 nanoflakes on carbon fiber and their H-inserted MnO2-x phases for high performance flexible super capacitors. The two-steps deposition of MnO2 enable to achieve uniform and crack free nano flakestructured films. As deposited electrodes showed promising capacitive performance in neutral electrolyte (0.5M Na2SO4) at slightly basic conditions with specific capacitance as high as 575 F/g. KOH-activation of the carbon fibers shows an improvement in capacitance up to 600 F/g at 1 A/g current density. We have also worked on a reliable and low cost approach to enhance the capacitive performance of these electrodeposited carbon fibers. The hydrogenation of these MnO2 electrodeposited electrodes exhibited remarkable improvement in capacitance up to 835 F/g. The superior capacitive performance can be attributed to the hierarchal deposition of two uniform, continuous and highly porous layers of stochiometric and H-inserted MnO2-x. Surface oxygen vacancies contribute to improve conductivity and kinetics of the surface redox reactions.
University 20 aout 1955-Skikda, Algeria
Nanostructured Fe65Si20Cr15 (at.%) powders were prepared by mechanical alloying in a planetary ball mill. Morphological, structural and magnetic characterizations of the powders milled several times were investigated by scanning electron microscopy, X-ray diffraction, Mössbauer spectroscopy and vibrating sample magnetometer.
Morphological observations have shown the existence of a broad distribution of size and shape of the powder particle. A decrease in the average particle size is observed during milling process. A mixture of substitutional bcc Fe(Si) (~ 29 nm) and bcc Cr(Si) (~ 45 nm) is obtained after 3 h of milling. On prolonged milling, all the as-milled powders exhibit non-equilibrium α-Fe(Si,Cr) solid solution with crystallite size of 19-23 nm. The variations of microstructural parameters such as crystallite size, r.m.s. microstrain, static Debye –Waller parameter and dislocation density as a function of milling time show good correlations among them.
Mössbauer spectra of the milled powders, recorded at room temperature, reveal the decrease of the average hyperfine field suggesting a random distribution of atoms during milling and point out the formation of the disordered bcc Fe (Si,Cr) solid solution. Magnetic measurements show the ferromagnetic behavior of the milled powders.
Keywords: Nanostructures; X-ray diffraction; Mössbauer spectroscopy; Magnetic Properties.
Laboratory of Physics Material, University May 8, 1945. Guelma, Algeria
In this work, we studied the theoretical calculations of electronic and optical properties of pure and co-doped TiO2. The optical absorption curves of co-doped TiO2 demonstrate the higher photo-response for visible-light than that of single doped one. The results provided a possible explanation for experimentally optical absorption observed broadening to visible-light in co-doped TiO2. This could provide theoretical basis for further developing of rutile TiO2 photo-catalyst and related experimental.
Keywords: TiO2, theoretical calculations, photo catalyst.
Industrial Chemistry Department, Faculty of Science, Ebonyi State University, Nigeria
The agricultural waste fibers are of notable economic and cultural importance all over the world are used for building materials, as a decorative product and as a versatile raw material. Agricultural waste fibers have significant potential in composite due to its high strength, eco-friendly nature, low cost, availability and sustainability. The agricultural waste is one of the most important problems that must be resolved for the conservation of global environment. The potential properties of agricultural waste fibers have triggered a lot of research to use these fibers as a material to replace man-made fibers for safe and environmentally friendly products. Agricultural waste is seen as one potential source of renewable energy. Their availability is obtained from oil palm plantations and some other agricultural industries such as rice husk, rice straw, sugarcane, pineapple, banana and coconut. Agricultural waste produces large amounts of biomass that are classified as natural fibers which until now only 10% are used as alternative raw materials for several industries, such as bio-composites, automotive components, biomedical and others. Characterization and comparison of the flexural, impact, water absorption and thickness swelling properties of corncob fiber, rice hull fiber, walnut shell fiber and flax shive fiber reinforced high density polyethylene (HDPE) bio-composites was studied. The composites were compounded by extrusion processing technique and results indicated that the corncob composites showed higher diffusion coefficient of 8.57 x 10-12m2s-1 while the flax shive composites showed least diffusion coefficient of 3.14 x 10-12m2s-1 compared to the rice hull and walnut shell composites. The rice hull composites showed higher values of thickness swelling of 12 %, while the flax shive composites showed the lowest value of thickness swelling of 0.5 % compared to the other composites. The flexural modulus and un-notched Izod impact strength increased with a decrease in flexural strength of the composites compared to the neat HDPE. Rice hull composites showed superior flexural strength of 22.5MPa. Flax shive composites gave superior flexural modulus of 3.0 GPa and walnut shell composites exhibited superior un-notched Izod impact strength of 52.5 J/m. The study showed that agro fiber sample load of 65 wt. % could be used in composite formulation with good result.
Keywords: Agricultural waste, Bio-composites, Sustainability, Mechanical properties, Water absorption.
Department of Industrial Chemistry, Faculty of Science, Ebonyi State University, Nigeria
In this study exfoliated graphite nanoplatelets (xGnP)-filled impact modified polystyrene (IMPS) composites were prepared at 2,4, 6 and 8 wt% xGnP with and without the addition of a coupling agent and compounded using melt mixing followed by injection molding. The coupling agent utilized in this study was polystyrene-graft-maleic anhydride. The nanoparticles used were xGnP with three different sizes: xGnP5 has an average thicknes of 10 mm, and an average platelet diameter of 5 μm, whereas xGnP15 and xGnP25 have the same thickness but average diameters are 15 and 25 μm, respectively. Results indicate that nanocomposites with smaller xGnP diameter exhibited improved impact properties for both pristine and compatibilized composites. However, unnotched and notched impact strengths as well as fracture initiation resistance were markedly deteriorated with the incorporation of xGnP. This brittle behavior in nanoplatelet-filled IMPS is explained using melt flow index and transmission electron microscopy.
Keywords: Impact properties, Rheology, Graphite, Coupling agent, Nanocomposite, Injection molding
Biography:
Dr. Ogah Anselm Ogah holds a PhD in Polymer Chemistry and Technology. He is a Lecturer in the Dept. of Industrial Chemistry, Ebonyi State University, Abakaliki, Nigeria and an adjunct lecturer with Dept. of Polymer and Textile Engineering, Nnamdi Azikiwe University, Akwa, Nigeria. He was a visiting scholar to the Composite Materials and Engineering Center, Washington State University, Pullman, WA, USA. Published over sixteen peer reviewed national and international journals.
1LMM, Laboratoire des Materiaux Magnetiques, Algeria
2LPCMA, Laboratoire physico-chimie des materiaux avances, Algeria
The purpose of this study is to exploit structural, electronic, magnetic and thermodynamic properties of the full Heusler Ag2CrGa compound using the method of calculation of linear Muffin-tin-orbital potential (FP-LMTO) in the L21 phase with the local approximations density (LDA), local spin density and the local spin (LSDA)density coupled(LSDA-couple). The calculation made on the structural properties such as modulus, pressure derivatives and electronic properties have enabled us to deduce the nature of this alloy which proved a metal. While the calculated magnetic properties has enabled us to evaluate the magnetic moment of the test compound Ag2CrGa and the magnetic moments of each constituent element of the latter. The calculated thermodynamic properties are apparent change in modulus, heat capacity and the Debye temperature [from 0 to 1600 °C].
Dedan Kimathi University of Technology, Kenya
In recent times, laser material processing has become a mainstream manufacturing technique in micromachining applications. This trend has been due to the various unique properties of the laser beam. Laser machining has desirable properties like flexibility and the ability to focus the beam to a small point makes it to be embraced leading to high energy density which allows cutting, welding, and drilling almost any material including silicon. In solar cell cutting of solar cell, the input parameters dictate the various output parameters after cutting. This process when it comes to customized solar panels faces challenges because not any input parameter combination produces the optimal output parameters for best quality solar cells. Therefore there is the need for optimization of the input parameters so as to produce quality solar panels.
In this research, the effect of laser beam and process variables (inputs) on cut quality attributes of solar cell was investigated. The input parameters selected for this study were: laser power, scan speed, and spot diameter. The quality attributes (outputs) which were investigated were: kerf depth, kerf width, and material removal rate for the process.
The input parameters were used in the design of experiment by Taguchi 9-orthogonal array implemented in Minitab17 software. The design provided nine experiments for unique combinations of the input parameters. Experiments were then conducted and the results were tabulated and analyzed.
The input factors were found to have a significant effect on the quality attributes of the solar cell. The kerf depth was found to increase with increasing laser power and decreased with increasing spot diameter and scan speed. The kerf width was found to increase with increasing laser power and spot diameter while it decreased with increasing scan speed. On the other hand, material removal rate was found to increase with increasing laser power and spot diameter while scan speed had the opposite effect. From this analysis, models relating the responses to the input factors were developed with the aid of the software.
Optimization process provided the solution for the desirable set values for the responses i.e. kerf depth was set at a target value of 0.1840mm, the kerf width was set to be minimal as possible, and the material removal rate was set to be at maximum as possible to reduce machining time. The optimal conditions were found to be; laser power at 126.67W, spot diameter at 0.4158mm and the scan speed at 3121mm/min.
An experimental validation of the optimized conditions was conducted obtaining kerf depth at 0.1839mm with a standard deviation of 0.00001, kerf width at 0.5828mm with a standard deviation of 0.0005 and material removal rate at 1456mm3/min with a standard deviation of 1.76. These experimental results showed conformity to the optimal conditions obtained using the software.
In conclusion, the study showed that the input parameters selected have a significant effect on the selected output parameters for the laser cutting process of solar cells. The study also showed that there exists a suitable combination of the input parameters in values which provide optimal output parameters.
Guelma University, Algeria
The structural, electronic properties of three chalcogenide compounds MgS, MgSe in rockslat phase have been investigated by using the full-potential linearized augmented plane-wave method (FP-LAPW) within density functional theory(DFT). We employed the local density approximation (LDA) and generalized gradient approximation (GGA) for the exchange-correlation (XC) potential. The equilibrium lattice constants are in agreement with the values reported in the literature. From the study of the electronic properties, we find that these binary compounds MgS and MgSe have indirect band gaps.
For ternary alloy MgSxSe1-x the study of these various properties are calculated, particularly the variation of structural and electronic parameters with concentration x. We focused our attention on the origins of bowing parameters corresponding to these physical properties.
In this study, we compare these predictions to the results already obtained experimentally as well as theoretical work in this regard.
Keywords: DFT, FP-LAPW, magnesium chalcogenides, ternary alloys, bowing parameter.
1Korea University of Science & Technology (UST), Republic of Korea
2Powder and Ceramics Division, Korea Institute of Materials Science (KIMS), Republic of Korea
Porous SiC proved its validity in microfiltration membrane fabrication, but application is limited due to its high fabrication cost. In this study oxidation bonding technique was used to fabricate SiC microfiltration membrane at low temperature. The oxidation behavior at different thermal treatments was related with pore morphology and ultimately the membrane permeance. By coating the clay-bonded SiC support with oxidation-bonded SiC and sintering the coating at 1100 °C for 1 h, we prepared a defect-free microfiltration membrane with pure-water membrane permeance of >210 l m-2 h-1 bar-1, an average pore size of 93 nm, and a narrow pore-size distribution.
Keywords: SiC membrane; Oxidation-bonding; Microfiltration; Permeance; Dip coating.
Unversity des Siences et de la Technology Houari Boumediene, Algeria
High-temperature X-rays diffractometry is used to study Ti2O3 rhombohedral oxide formed by reduction of titanium dioxide, under vacuum and in the presence of graphite or metallic titanium. The sesquioxide is charac-terrized by a homogeneous field of very low oxygen pressure, both boundary phase appearing independently from one another between 800 and 1715°C. The c/a = 2.660 value for Ti2-xO3 oxidized from of the equivalent hexagonal cell reaches c/a = 2.735 for Ti2O3 reduced form, which does not undergo quenching (c/a = 2.640 at room temperature).
1Natural Sciences Research Institute, University of the Philippines, Philippines
2Institute of Chemistry, University of the Philippines, Philippines
Porous materials such as chiral metal-organic frameworks (MOFs) have attracted growing research interest for their application promise in material science, energy storage, asymmetric catalysis, and enantio selective separation of racemic molecules. Despite the numerous researches in MOFs, there are only few reports on biologically important amino acids, histidine in particular, on its use as bridging ligand in the construction of open-framework architectures. In this work, hydrothermal synthesis was used to prepare compounds based on transition metals and histidine. The coordination assembly of imidazole side chain of histidine with divalent nickel ions in aqueous condition yielded violet prismatic solids. Single crystal X-ray diffraction (XRD) analysis showed Ni (C6H8N3O2)2 • H2O that has a monoclinic (C2) structure with lattice parameters, a = 29.41, b = 8.268, c = 6.314 Å, β = 90.01 ˚. Powder X-ray Diffraction (XRD), Thermo gravimetric Analysis (TGA), Circular Dichroism – Optical Rotatory Dispersion (CD-ORD), and Fourier Transform – Infrared Spectroscopy (FT-IR) are conducted to further characterize the crystals. To investigate the enantio selective property, qualitative assessment of the synthesized MOFs by adsorption study with a racemic mixture of 2-butanol and CD spectroscopy was performed.
Research Advisor, Vice Chancellorʼs Research Group, University of Burdwan, India
Development of smart material using ionic polymer-metal composites (IPMCs) is a demanding area of research. The IPMCs are now recognized to have potential applications in developing bio-mimetic sensors, actuators, transducers, and artificial muscles. The IPMCs offer several advantages such as bio-compatibility, low power consumption and miniaturization. We have been engaged in developing IPMC based actuators and sensors. Recently we have reported results of the actuation and sensing studies of a five-fingered miniaturized robotic hand fabricated by using IPMC. Very recently, we have explored the possibility of using Nafion based IPMC for sensing the rhythm of human pulse and hear rate. In this talk the concept of a novel pulse rate sensing device is introduced exhibiting the proof-of-principle of the mechano-electrical functions of the device, namely IPMC film prepared by surface platinization of the ionic-polymer film.
Keywords: Ionic-Polymer-Metal-Composite (IPMC); Actuators; Sensors.
Mechanical Design and Materials Department, Faculty of Energy Engineering, Aswan University, Egypt
Oxygen reduction reaction (ORR) catalysts are the heart of eco-friendly energy resources particularly low temperature fuel cells. Although valuable efforts have been devoted to synthesize high performance catalysts for ORR, considerable challenges are extremely desirable in the development of energy technologies. Herein, we report a simple self-polymerization method to build a thin film of dopamine along the tubular nanostructures of multi-walled carbon nanotubes (CNT) in a weak alkaline solution. The dopamine@CNT hybrid (denoted as DP@CNT) reveals an enhanced electrocatalytic activity towards ORR with highly positive onset potential and cathodic current as a result of their outstanding features of longitudinal mesoporous structure, high surface area, and ornamentation of DP layers, which enable fast electron transport and fully exposed electroactive sites. Impressively, the as-obtained hybrid afford remarkable electrochemical durability for prolonged test time of 60,000 s compared to benchmark Pt/C (20 wt%) catalyst. Interestingly, the synergetic effect of nanostructured DP and CNT can significantly boost the electronic configuration and exposure level of active species for ORR. Therefore, the existing carbon-based porous electrocatalyst may find numerous translational applications as attractive alternative to noble metals in polymer electrolyte membrane fuel cells.
University of Sharjah, UAE
The recent development of synthesis techniques has enabled the development of new materials and complex systems for which properties and functions are adjustable over several size scales, ranging from nanometers to centimeters. Functional materials, called smart, have taken now days an important place among the most studied research topics. Various applications have emerged as a result of this progress. As an example, we will discuss the following two cases:
Conductive gas sensor: SnO2 as example
During the last years and following the increase in problems related to air pollution, the work of basic and applied research in the field of gas detection, particularly the detection of pollutants, have become more and more important. Progress in the field of developing and shaping solid materials and the new possibilities offered by micro and nano-technology have contributed to the research and development of new devices for the detection of polluting gases in the air and in particular, reducing gases such as carbon monoxide, methane, H2S ... etc. Many devices operate then by using electrical conductivity variation of apolycrystalline semiconductor oxide as a result of gas-surface interactionon the grain boundaries.
Despite a very large number of studies on the effect of NP metal doping on the sensing properties of SnO2, the role of these additions has so far remained largely unknown. This ignorance has been an impediment to the development of sensitive and reliable sensors. We try to propose and present the different mechanisms used to explain the role of these metal additions on the electrical properties of SnO2, and its response in the presence of a reducing gas. Inedited experiments using in-situ and simultaneous X-ray absorption spectroscopy and electrical conductivity and CO gases measurement present the main achievement of this work.
Programmable Optical Components
The need for next-generation photonic systems has led to the adoption of the technique known as multiplexing or “dense wavelength division multiplexing” to increase the capacity of existing optical networks. This approach requires the development of new concepts of components to ensure multiplexing, demultiplexing, switching, routing and control of each wavelength of the optical signal. This creates considerable pressure on photonic components currently used for optical signal processing. The trend will shift significantly to miniaturized optical devices with low power consumption and low cost, which not only provide superior performance than the current cumbersome devices, but also replace the functions of microelectronics. Photonic components such as networks waveguide / fiber embedded in anelectronically controllable geometry could form the basis of the new generation of “Programmable photonic components”.
Biography:
Mounir Gaidi, Doctor in physics (Ph.D Material Sciences from the national Institute of polytechnic of Grenoble-France)), now he is an Associate professor of physics at Sharjah University. He worked for many research institutes such as National center of Scientific Research (France), National Institute of scientific Research (Canada) and the Research and technology center of energy (Tunisia). Currently Dr. MounirGaidiʼs researches focus on Nanomaterials for photovoltaic solar cells applications, Doped and un-doped metal oxide Gas sensors, Nanomaterials for photocatalysis and Multiferroic materials for opto-electronic application. He is also expert in Thin films elaboration by physical (PLD-sputtering), chemical process, electrochemical and pyrosol techniques. Dr Mounir co-authored more than 60 papers and books in the field of nano and smart materials applications.
Department of Electrical Engineering, University Hassiba Benbouali, Algeria
Doubly-fed induction generator (DFIG) wind turbin e has been extensively used in wind energy conversion system due to its fine energy capture performance, good controllability and simple implementation. In this paper, we examine a non linear control based on the high order sliding mode (HOSMC) for the direct torque control (DTC) of a DFIG incorporated in a wind energy conversion system and associated with a storage unit. This research is carried out to reach two main objectives. Firstly, the DFIG rotor side converter is controlled by HOSMC-DTC in order to achieve good performances. The second objective is the association a storage unit, in parallel with the DC bus, to obtain a smooth as much as possible the power supplied to the network grid. Finally, the simulation results showed that DFIG wind turbine with storage unit could provide a much smoother power output at different wind conditions comparing with the conventional DFIG wind turbine.
Keywords-Component; Doubly Fed Induction Generator (DFIG); Direct Torque Control (DTC); High Order Sliding Mode Controller (HOSMC); Storage unit.
Cairo University, Faculty of Engineering, Egypt
Cabin thermal comfort is predominantly impacted by the interior car cabin temperature. This study aims to investigate the impact of orientation of air vents on the private car cabin temperature when cooling is started. In contrast, the cabin temperature depends on the size of the cabin, the number and shape of the air vents and the collective flow of the entire HVAC system and the interior materials of the dashboard, trims and seats. In this study numerically investigated thermal comfort in a car cabin resulting of the solar radiation. Normally, the air vents in the car cabin is manually adjustable to adjust the airflow direction. Computational fluid dynamics (CFD) investigation was performed by using FLUENT 18.0 as a solver and a CFD processor developed by ANSYS Inc., in which the solar load model is embedded. A three dimension (3D) computational model for the car cabin has been conducted with ICEM CFD software for good quality grid generation; more than 5,000,000 grid nodes. The performance of HVAC system is characterized by air flow patterns, temperature, relative humidity contours as well as the most commonly used comfort parameters the predicted mean vote (PMV) and the predicted percentage of dissatisfied (PPD) based on Fanger model. With the help of CFD simulations it is shown that oriented air vents with 30°provide a better thermal comfort for passengers. The study showing that the calculated temperature near the driver increased by about 1.5°C resulting of the solar radiation. The study showing that the impact of inlet air temperature from vents has better effect on thermal comfort instead using higher air change per hour (ACH) at the same vent direction.
Keywords: Thermal comfort, CFD, HVAC, Car cabin temperature, solar radiation.
1Department of Physics, Loughborough University, UK
2Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, China
3Collaborative Innovation Center of Quantum Matter, China
Here we show that in electron doped copper oxides oxygen orbitals in CuO2 planes can be polarised with electron doping to form spin-orbital polarons. We introduce a concept of such a polaron. In these spin-orbital polarons, electrons are self trapped in one dimensional channels created by a polarisation of the oxygen orbitals forming an elongated filament. All these filaments have two possible orientation, along the main diagonals of the elementary CuO2 square. When the density of doped electrons increases many filaments are formed. They may be condense in a big filament or crossing each other perpendicularly, i.e. under right angle and therewith creating a conducting quasi-one-dimensional web. The web and the AF state are coexisting with each other at small doping. When doping increases the web of filaments is modifying the AF correlations and leads to a series of quantum phase transitions.
We show that with electron doping here may arise an issue related to a polarisation of the oxygen orbitals in CuO2 plane, which can lead to a formation of new spin-orbital polarons. These polarons combine the features of the conventional electron-phonon polarons and of magnetic polarons8. They can form nanofilaments as spin bags. The multi-polarons may naturally arise in oxide materials due to the screening of the electron-elecron interaction by oxygen polarisation. Such multipolaron network provide the anomalous in-plane and out-plane magnetoresistance of electron-doped cuprate La2-xCexCuO4±δ[1]. We made a detail comparison of the developed theory with experiments and show that the spin-orbital polarons may describe these experiments very well.
Biography:
Fedor V Kusmart is Vice Head of Physics Department, Loughborough University, United Kingdom. For ten years Kusmartsev has been leading and managing the large multi-stakeholder research consortium – the European Network-Programme “Arrays of Quantum Dots and Josephson Junctions”(AQDJJ). This very large consortium included 75 research teams with very different cross-disciplinary background, from Physics, Chemistry, Engineering, Mathematics and Computing Departments of 75 EU universities distributed over 12 EU countries (Austria, Belgium, Czech Republic, Denmark, Finland, Germany, Italy, Slovak Republic, Spain, Sweden, Switzerland and UK) and have very different cultural, academic and industrial backgrounds. The European Science Foundation assessment reports unanimously stated that the strong success of the AQDJJ consortium work was
“due to the leadership of the AQDJJ chairman, Prof Fedor v Kusmartsev”. He is a Member of International Editorial Advisory Boards: journal N1: Advances in Condensed Matter Physics (since 2007); journal N2: Econophysics, New Economy and Complexity (since 2010). N3: Scientific Reports (NATURE, since 2013); was a guest editor of several high profile journals: Journal of Physics A(2003), Superconducting Science and Technology(2009), J. of Modern Physics B(2008).
1Department of Chemistry, College of Science, Sultan Qaboos University, Oman
2Department of Chemistry, University of Bath, UK
New neutral tetra-ferrocenyl-ethynylpyridinyl copper complexes have been formed by the coordination-driven self-assembly of the ferrocenylethynyl-pyridine Ligand (L) and the copper (I) halides (I-, Br- and Cl-) forming cubic L4(CuI)4, and rhomboid L4(CuBr)2, L4(CuCl)2. However, in the presence of triphenylphosphine (PPh3) under similar conditions, the reactions gave new neutral di-ferrocenyl-ethynylpyridinyl copper complexes, L2(CuI)2(PPh3)2, L2(CuBr)2(PPh3)2, and L2(CuCl)2(PPh3)2. Ferrocenylethynyl functionalized pyridine ligand provided the coordination site to connect ferrocenyl units through the copper clusters.
The ferrocenylethynyl-copper cluster materials oxidize under mild condition giving electro-crystallization of oxidized products. EDX analysis indicated formation of partially- and fully-oxidized products. These results were complimented by Raman analysis. SEM showed oxidation products having distinct morphologies. Some of these morphologies of the electrodeposited Cu-based microstructure are of high recent interest for fundamental studies and for potential applications in catalysis and other fields.
Herein, we will present the convenient synthesis, electrochemistry, SEM, EDX, etc. and future prospect of the electro-crystallized multi-ferricenyl materials.
The body of the abstract should describe your research, results and conclusions of your study.
Biography:
Dr. Hakikulla Shah was born in Dhule, Maharashtra, India, in 1982. He received the B.Sc. degree in Chemistry from the North Maharashtra University, Jalgaon, India, in 2004, and the M.Sc (Major: Analytical Chemistry) Chemistry from Wadia College, Pune University, India. He pursued his Ph.D. degree in Chemistry (Organometallics) from Sultan Qaboos University, Oman in 2013. During his Ph.D. he also obtained a research scholarship from British Council, UK from a British council PMI-2 Research collaboration in the Middle East grant. During his Ph.D. training Dr. Shah stayed half of every year at University of Bath, UK from 2010-2012 as a British Council visiting scholar. Currently, Dr. Shah is working at Department of Basic Science, in College of Applied Science at AʼSharqiyah University, Oman.
Fayoum University, Egypt
Water splitting is the key step towards artificial photosystems for solar energy conversion and storage in the form of chemical bonding. The oxidation of water is the bottle-neck of this process that hampers its practical utility and hence efficient, robust, and also easy to make catalytic systems based on earth abundant materials are of exceptional importance. Here, we present an in-situ generated cobalt catalyst [Co(II)(TCA)2(H2O)2] (where TCA = 1-Mesityl-1,2,3-1H-triazole-4-carboxylate) that efficiently conducts photochemical water oxidation at near-neutral conditions. The catalyst showed high stability under photolytic conditions for more than 3 h of photoirradiation. During electrochemical water oxidation, the catalytic system assembled a catalyst film, which proved not to be cobalt oxide/hydroxide as normally expected, but instead and for the first time, generated a molecular cobalt complex incorporating the organic ligand bound to cobalt ions. The catalyst film exhibited low overpotential for electrocatalytic water oxidation (360 mV) and high oxygen evolution peak current density of 9 mA cm-2 and 2.7 mA cm-2 on GC and ITO electrodes at only 1.49 and 1.39 V (vs. NHE), respectively, under neutral conditions. Furthermore, DFT calculations predict a mono-nuclear oxidation mechanism and show that this Co(TCA)2.2H2O catalyst lies very close to the top of the theoretical volcano plot. Based on these computational results, a small modifications of this type of catalyst can lead to a superb –easily synthesized – industrial water oxidation catalyst. Our finding, exemplified on the in-situ generated cobalt complex, might be applicable to other molecular systems and suggests that the formation of catalytic film in electrochemical water oxidation experiments is not always indication of the catalyst decomposition and formation of nanoparticles.
Applied Physics and Astronomy Department
University of Sharjah, United Arab Emirates
The size and concentration of voids in biomedical materials plays an important role in the structural integrity of these materials. The later has an impact on performance and quality of such materials. To monitor and assess the size and distribution of voids that are dispersed within the multiphase material, one needs a noninvasive technique that preserves the structure of the material. Ultrasound has proven to be an excellent candidate to provide quantitative assessments of the voids size concertation allowing theoretical models to be used to assess the elastic properties of such materials as the size and concertation of voids is varied.
In this paper, we present the results of an ultrasonic investigation carried out to measure bubble size and distribution in multiphase soft biological materials with bubbles impeded. After a brief discussion of the ultrasonic technique, the results of longitudinal velocity and attenuation measurements will be presented, which will be sued in elasticity models to characterize the elastic properties of the materials. To further investigate this, materials with wide range of void fractions were examined. The results clearly show the sensitivity of longitudinal ultrasonic and attenuation coefficient to void factions within the sample, highlighting the potential of ultrasound as a noninvasive tool for probing the properties of materials with voids impeded.
Keywords: Ultrasonic, void fraction, longitudinal velocity, attenuation coefficient, elastic properties.
1School of Optoelectronic Information, University of Electronic Science and Technology of China, China
2School of Engineering, Brown University, USA
A large shift in the optical constants of phase-change vanadium dioxide (VO2) enables active control of its transmission and reflection properties. When incorporated as a structural element of a metamaterial, such a dynamic control opens door to properties and functionality that are otherwise unavailable in nature materials, and to tunable and reconfigurable optical devices. In this talk, we present thermal and electrical tuning responses of two VO2-integrated metamaterials. First, we realize a tunable infrared metasurface made of a plasmonic antenna array atop a VO2 film backed with a reflecting metallic plane. By triggering the insulator-to-metal phase transition of VO2, the metasurface resonance is shifted by 3.5% in frequency, which results in a reflectivity change of 30% in magnitude. Secondly, we fabricate a VO2-integrated planar multilayer structure, which exhibits a broadband absorbance tuning. By mediating the effective impedance of the multilayered thin films with VO2 phase transition, a tuning magnitude of more than 60% is measured for absorption over the wavelength ranges of 5-9.3 μm and 3.9-8.2 μm. Such tuning of resonance frequency and absorbance can be deployed for reconfigurable bolometric sensing, camouflaging and modulation of infrared radiations.
Biography:
Zhijun Liu, Ph.D., currently a Professor at University of Electronic Science and Technology of China. He obtained his Ph.D. from Princeton University in 2008. He then did his postdoctoral research at Brown university and University of California Los Angeles. Since 2013, he has been on faculty in the School of Optoelectronic Information at University of Electronic Science and technology of China. He was awarded National 1000 Young Talents Program of Chinaand Honorific Wallace Memorial Fellowship at Princeton University. His current interests are md-infrared and terahertz metamaterials and optoelectronics.
1Laboratory of Mechanics and Industrial Processes, Chemical Sciences Research Team, Mohammed V University, Morocco
2Laboratory of Physical Chemistry of Materials and Catalysis, Department of Chemistry, Faculty of Sciences, Mohammed V University, Morocco
3Hassan II Academy of Science and Technology, Morocco
High active, reusable solid catalyst was obtained from eggshell by a simple heat treatment method. Calcined eggshell was used in the transesterification of vegetable oil with methanol to produce biodiesel. In order to explain the effect of calcination temperature, we investigated the calcination process of eggshell with thermal gravity analysis (TGA), X-ray diffraction (XRD) pattern, Fourier transform infrared spectroscopy (FTIR), and Scanning Electron Microscopy (SEM) analysis.
The yield of biodiesel was affected by reaction variables, such as methanol/oil ratio, catalyst amount and reaction time. For the following reactions, all the catalyst was prepared by calcinning eggshell at 800 °C for 2 h. The produced biodiesel was characterized by techniques such as Fourier transform infrared (FTIR) spectroscopy, and nuclear magnetic resonance (NMR) spectroscopy. The experimental results showed that the yield increase with increasing the methanol/oil molar ratio, and reached a maximum when the ratio was above 9 and 3% of catalyst.
The method of reusing eggshell waste to prepare catalyst could recycle the waste, minimizing contaminants, reducing the cost of catalyst, and making the catalyst environmentally friendly. This high efficient and low-cost eggshell catalyst could make the process of biodiesel production economic and fully ecologically friendly.
Keywords: Eggshell waste; Biodiesel; Catalysis; Transesterification, Heterogeneous catalysis.
Biography:
Kaoutar KARA received the masterʼs degree in Surface Hydrology and Water Quality from Sidi Mohamed Ben Abdellah University of Science and Technology, Fez, Morocco. She is currently a PhD student at the Laboratory of Mechanics and Industrial Processes. Chemical Sciences Research Team. Mohammed V University, Rabat, Morocco. Her research interests are in waste fish valorization, biodiesel production and green energy.
1Materials Science and Photo-Electronics Lab., Kuwait
2Electrical Engineering Department, Southeast University, China
3Department of Electrical, Electronic and Information Engineering, City University London, United Kingdom
A criterion of the energy efficiency of iron-boron-silicon metallic glasses in sulfuric acid solutions is proposed for the first time (1). The criterion has been derived based on calculating the limit of the ratio value of the conductivity of a metallic glass in aqueous solution to the conductivity of the metallic glass in air. In other words, the conductivity ratio of a metallic glass in aqueous solution to the conductivity of the metallic glass in air =1, was applied to determine the energy efficiency of the metallic glass in the aqueous solution when the conductivity of a metallic glass in air became equal (decreased) to the steady conductivity of the metallic glass in aqueous solution as a function of time of the exposure of the metallic glass to the aqueous solution. This criterion was not only used to determine the energy efficiency of different metallic glasses, but also, the criterion was used to determine the energy efficiency of metallic glasses exposed to a wide range of sulfuric acid concentrations. These conductivity values were determined by the electrochemical impedance spectroscopy (EIS). In addition, the criterion can be applied under diverse test conditions with a predetermined period of the operational life of the metallic glasses as functional materials. Furthermore, variations of the energy efficiency of the metallic glasses as a function of the acid concentration and time were produced by fitting the experimental data to a numerical model using a nonlinear regression method. The profiles of the metallic glasses exhibit a less conservative behavior of the energy efficiency than the proposed analytical criterion.
Keywords: Energyefficiency; Metallic glasses; Conductivity; Electrochemical impedance spectroscopy; Electrical power consumption; and Sulfuric acid.
References: K Habib, W Jiang, B M A Rahman, and K T V Grattan,”Energy efficiency of iron–boron–silicon metallic glasses in sulfuric acid solutions”, Materials Research Express. February 2017, accepted in press. DOI: 10.1088/2053-1591/aa60dc
Bitlis Eren University, Metallurgical and Materials Engineering, Turkey
Control and manipulation of the parameters scuh as shape, phase, amplitude and frequency of the electromagnetic pulses are very important in fundamental science and engineering and telecomunication. As an another parameter, electromagnetic pulses are able to carry spin and orbital angular momentum2. Orbital angular momentum carrying lasers are called as twisted light or optical vortex. The angular momentum of light can be manipulated and transferred to quantum systems3. In this study, we investigate the effect of angular momentum transferred to the quantum systems on electron dynamics, the induced current and induced magnetic pulse4,5,6. We will show that a laser pulse in the range of picosecond and femtosecon can be transformed to a same range magnetic field.
Keywords: Orbital momentum, ultrafast laser, magnetic pulse
References
1. Moskalenko, A. S., Matos-Abiague, A., & Berakdar, J. (2006). Revivals, collapses, and magnetic-pulse generation in quantum rings. Physical Review B, 74(16), 161303.
2. Allen, Les, et al. “Orbital angular momentum of light and the transformation of Laguerre-Gaussian laser modes.” Physical Review A 45.11 (1992): 8185.
3. Volke-Sepulveda, K., Garcés-Chávez, V., Chávez-Cerda, S., Arlt, J., & Dholakia, K. (2002). Orbital angular momentum of a high-order Bessel light beam. Journal of Optics B: Quantum and Semiclassical Optics, 4(2), S82.
4. Köksal, K., & Berakdar, J. (2012). Charge-current generation in atomic systems induced by optical vortices. Physical Review A, 86(6), 063812.
5. Matos-Abiague, A., & Berakdar, J. (2005). Photoinduced charge currents in mesoscopic rings. Physical review letters, 94(16), 166801.
6. Quinteiro, G. F., and J. Berakdar. “Electric currents induced by twisted light in quantum rings.” Optics express 17.22 (2009): 20465-20475.
7. Köksal, K., & Koç, F. (2016). Optical manipulation of photo-induced current in spherical semiconductor quantum dots by optical vortices. Philosophical Magazine, 96(25), 2686-2695.
8. Köksal, K., & Koç, F. (2017). Spin and orbital angular momentum transfer into Ga n As n nanocage: The change in induced magnetic field by tuning the light parameters and size of the molecule. Computational and Theoretical Chemistry, 1105, 27-32.
9. Köksal, K., & Koç, F. (2017). The effect of twisted light on the ring-shaped molecules: The manipulation of the photoinduced current and the magnetic moment by transferring spin and orbital angular momentum of high frequency light. Computational and Theoretical Chemistry, 1099, 203-208.
1Department of Chemistry, Texas A&M University, USA
2Department of Chemistry, Texas A&M University at Qatar, Qatar
Coplanar torsional conformation plays a key role in shaping the unique characteristics and functions of conjugated organic macromolecules. It is still an elusive task, however, to control the coplanar conformation of conjugated polymers for materials performance. We aim to establish general synthetic methodology and comprehensive structure-properties correlations of coplanar pi-systems, through synergistic approaches combining chemical synthesis, process engineering, and materials characterization. In order to achieve this goal, we have designed and implemented multiple strategies, including the use of non-covalent bridging bonds, the employment of dynamic covalent reactions, and the use of highly efficient annulation reactions. Efforts were also made to solve the challenges associated with low solubility of this class of materials for characterization and processing. Unique optical, electronic and mechanical properties of these new materials are investigated and optimized for advanced applications.
1LPMR, Departement des Science de la Matiere, Faculty des Sciences et Technologie, Univ-Souk-Ahras, Algeria
2LESIMS, Departement de physique, Faculty des Sciences, Univ-Badji Mokhtar, Algeria
CuGaTe2 are very promising absorber materials for thin film photovoltaic devices due to their direct band gaps, which well match with the solar spectrum and their high absorption coefficients. Thin films of about 1μm of thickness have been prepared by flash evaporation technique. The structural and optical properties of these samples were investigated. X-ray diffraction analysis revealed that the films present the chalcopyrite structure with (112) preferred orientation. Optical measurements have been carried out in the wavelength range 200-3000 nm. From the transmission measurements we have deduced an absorption coefficient and optical band gap of 4.104cm-1 and 1.21eV respectively.
Keywords: Thin films, flash evaporation, chalcopyrite.
1Department of Chemistry, Texas A&M University at Qatar, Qatar
2University of Michigan, Materials Science and Engineering, USA
Soluble conjugated polymers have nowadays attracted broad academic and industrial spotlight as innovative materials of easy tuneable optical and electronic properties.1 These properties translate into various optoelectronic applications such as organic solar cells, light-emitting diodes (LEDs), and thin film transistors. The pivotal parameters that define characteristics of conjugated polymer based devices are of chemical (structure, solubility, mass) and mechanical (macroscopic) nature.2 Although the physical properties CPs is determined by designed chemical structure, critical alterations result from variations of the nanostructure of the polymer in its solid state.3 Therefore the complete optoelectronic potential of CP based device can be fully assessed only with the optimal conjugated chains alignment.
We envisioned thermal and UV induced post processing of conjugated polymers predesigned to dramatically change their properties in given conditions by removal of nonconductive side chains and reducing interlayer distance.
1. A. J. Heeger, Chem. Soc. Rev. 2010, 39 2354–2371.
2. Kline, R. J., McGehee M. D. Journal of Macromolecular Science Part C: Polymer Reviews, 46: 27–4.,
3. Chung, K. MRS Communications, 2015, 5(2), pp. 169–189.
1Centre for Advanced Materials & Industrial Chemistry, School of Science, RMIT University, Australia
2Einstein Straße 29A, Germany
3RMIT Microscopy & Microanalysis Facility, RMIT University, Australia
Hierarchical porous materials have received a tremendous research interest because of their potential role in overcoming mass transport limitations of single-mode porous materials in various industrial applications. This work reports the synthesis of a novel hierarchical tri-modal porous silica using 7.5 molar ratio of 1,2,4-trimethylbenzene:tri-block copolymer, EO20PO70EO20. The pore size distribution curve shows the presence of three types of pores w h g d m ~8 25 d 89 m. E m p m g h m h existence of macropores, larger ordered mesopores, and smaller ordered mesopores. This research provides new insights to develop novel tri-modal porous silica materials with versatile applications.
Keywords: Hierarchical porous materials, tri-modal porous silicas, CO2 reforming of CH4, catalysts, hydrothermal assisted sol-gel method.
Faculty of Engineering, Cairo University, Egypt
The current work presents a comprehensive study of the factors affecting cold cracking of welds to find out how can we produce crack-free joints. The complicated interrelations between these factors are analyzed. The Implant cracking test is developed to quantitatively study the effect of each factor on the susceptibility of steel to Heat Affected Zone (HAZ) cold cracking. Implant static fatigue limit (RSFL) can be determined experimentally for the given material and welding conditions. To avoid cold cracking in weld (HAZ), RSFL must be greater than the stresses arising in the welded joint (RS). Implant weldability tests were carried out on C-Mn and High Strength Low Alloy steels (HSLA) with a carbon equivalent (CE) ranging from 0.38 to 0.48% and 0.52 to 0.68%, respectively. Static fatigue limit is modeled as a function of base metal chemical composition including carbon equivalent, welding variables and weld metal diffusible hydrogen content. HAZ hardness is a function of base metal chemical composition and welding variables. Static fatigue limit can be modeled as a function of HAZ hardness and weld metal diffusible hydrogen.
Direct determination of stresses arising in welded joints, either analytically or experimentally, is complicated and difficult to obtain accurately. Here, an indirect technique is proposed and applied. In our experiments two different types of steels: St 52-3 and 17Mn4 with thicknesses 12 mm and 20 mm are used. Rigid steel structures are designed and welded using wide scale of welding parameters and electrode coatings. For each joint type, static fatigue limit values are calculated, and sections of the welded joints are examined microscopically for cracking. For each specified joint, the crack/no crack limiting value of RSFL is taken as the critical RS value. The critical static fatigue limits for butt-, T- and cruciform joints are determined experimentally. Nomograms are constructed to predict safe welding conditions to avoid cold cracking in single and multilayer welding.
Texas A&M University, Qatar
Plastic electronics has made great commercial and scientific progress over the past decade, predominantly driven by the potential of applications such as organic field effect transistors (OFETs) for flexible backplanes and e-paper, organic light emitting diodes (OLEDs) for large area lighting and displays and organic solar cells (OPV) for large area energy generation. Much of this work has been motivated by the fact that organic semiconductors can combine the superb mechanical and processing characteristics of plastics with a variety of printing techniques, enabling large-area, low-cost manufacturing. There has been an intensive worldwide research effort on the development of stable, conjugated organic semiconducting polymers as potential replacements for conventional silicon, the benchmark large area amorphous semiconductor. ID TechEx, the UK-based market research company, “estimates that over the last two decades global investments into plastic electronics technologies exceed US $10 billion, and predict that this will grow to almost US $25 billion by 2020”.
The ecological and commercial motivation to implement the use of plastic electronics is compelling. Recently, such efforts have facilitated the development of thin film transistors for backplane applications such as e-paper. The ability to operate in ambient atmosphere without costly and rigorous encapsulation barriers to avoid water and/or oxygen is an important step towards commercialization. Research for cleaner alternatives of energy generation and advanced energy permitting devices has journeyed down an interesting path. The exploration of conjugated organic materials within the context of energy has led to the development of devices with great potential for utilization and exploitation within the near future, where perhaps the emergence of hybrid materials or the utilization of nano-architectonics will be of paramount importance to aid in the development of state of the art nanotechnology and its utilization within energy related themes. Meanwhile, further reducing of the cost is expected in the next decade as a result of designing next generation of energy devices (e.g. supercapacitors, solar cells, Li-ion batteries, fuel cells).
Organic PV active layers (especially polymer based materials) have the latent potential of solution based processing of the active layers, offering the attraction of low-cost, continuous roll-to-roll or printing processing of large area devices upon flexible substrates. These deposition techniques of the active layers may allow devices to meet the $15/m2 target; for comparison paint costs about $1/m2. Furthermore, organic active layers offer infinite design space by virtue of the polymer architectures, providing potential for layers design and tunability to suit specific energy supply criteria.
The development of more efficient energy-producing devices and cleaner energy generation alternatives continue to advance. The investigation of polymeric materials within the context of solar energy has thus far yielded devices with great potential. Through systematic chemical modification, the performance of OPV cells has advanced impressively over the last three years, with power conversion efficiency (PCE) now routinely surpassing 8%, and attracting industrial interest in commercializing this technology.
The synthesis of well-defined conjugated molecules/polymers is a considerable synthetic challenge that many excellent research groups have addressed over the last decade or so. A particularly promising class of potential donor/acceptor materials for use in BHJ solar cells and organic electronics are the aromatic donor-acceptor amido pigments diketopyrrolopyrrole (DPP) and isoindigo and the electron deficient bis-Thiazole (Figure 1).
Here, an electron-rich aromatic segment is positioned adjacent to a highly electron-deficient amide link typically known as a push-pull chromophore. When incorporated into small molecules or polymers, this structure affords very narrow band-gaps capable of harvesting a large percentage of the solar flux. Both DPP and isoindigo units have recently been used to construct some of the most efficient organic solar cells to date, and the present work capitalizes on these advances, and goes beyond.
Here we will present our synthetic efforts on developing the novel polymeric materials containing the three structures shown in figure 1, particular emphasis on a suit of carefully selected sidechains, which has provide access to a wide range of monomers with tuneable solubility (with either short or long, branched or linear alkyl chains). Moreover, the initial synthetic targets will specifically be the introduction of branched ocytyl-decyl chains as well as linear hexadecyl alkyl chains since they have both been used in other high efficiency conjugated polymers-the latter are known to enhance interchain interdigitation and close π-π stacking.
Department of Mechanical Engineering, University College London, UK
Electrospun polystyrene (PS) fibres has been shown to possess better sorption performance than the commercial melt blown polypropylene (PP) sorbent. On a microscale level, the oil - sorbent interaction and its effect on the sorption behaviour is yet to be fully understood; as different parameters has been attributed to the sorption behaviour of fibrousmat. In this study we used the drop-on-fibre theory to quantitatively evaluate the oil adherence potential of single filament of electrospun PS and melt-blown PP fibre to different oils.
Sunflower and motor oils, with completely different viscosity values were used to evaluate the drop volume and adhesive energy distribution on the fibres. Sunflower oil was observed to break up into more barrel shaped droplets on both fibres and exhibits a higher contact angle (CA), with an average CA of 37.82° and 37.38° on the PS and PP fibreS respectively. Motor oil on the other hand, showed an average contact angle of 35.04° and 29.82° on the fibres respectively. Strong link between the chemical structure and the oil affinity of single filament was observed as PS fibre was seen to exhibit sorption performance of between 3 – 6 times those of Meltblown PP.
This study further elucidate the oil adsorption affinity of electrospun polystyrene fibre down to a microscale level of a single filament in comparison to Meltblown PP fibre. It also characterizes the two sorbent fibres and gives an in-depth knowledge about the importance of material choice for sorbents used for oil spills clean up.
Biography:
Muftau Jide Akanbi, holds a first and second degree in Mechanical Engineering from the University of Ilorin, Nigeria and University College London (UCL) respectively. He is currently pursuing his PhD degree under the supervision of Suwan Jayasinghe. His research interest include engineering and characterization of novel fibrous material for oil spill remediation. He also has a strong interest in electrospinning and functionalization of scaffolds for tissue engineering, biological and environmental application.
Centre for High Energy Physics, University of the Punjab, Pakistan
The density-functional theory (DFT) for quantum electrodynamics provides the significant role for Kohn Sham (KS) system. The resulting KS systems for many body methodologies were specified for different values of effective potentials that give the impression of particle–particle (Coulomb) interaction and the particle–photon interaction. Applications of these procedure and methodology to KS potentials enhanced and facilitated the calculations that were become numerically possible.
Department of Mechanical Engineering British University in Egypt, Egypt
In this study, experiments are conducted to study the erosion behavior of various coatings on glass-fiber reinforced epoxy polymer composite (GFRP) substrate by silica sand particlesfor applications of wind turbine blades. The effects on erosion rate of impingement angle (0°-90°), erodent velocity (20-80 m/s), coating types (2K acrylic-base, polyurethane-base, polyurea-base) and coating thicknesses (120-2000 μm), erodent size (300 μm) are investigated. Additionally, the results were statistically analysed using ANOVA and plotted using response surface methodology (RSM) to obtain in-depth understanding of significant factors affecting erosion. Moreover, predictive regression models were generated in the form of equations and contour plots to estimate erosion responses at various factor combinations. Results show that elastomeric coating application on GFRP substrate can lead to reduction in erosion rate of up to more than 96% compared to uncoated GFRP. However, at other parameter combinations, an increase in erosion rate of about 4.5% due to coating is noted. Additionally, the application of coating on GFRP at certain parameter combination leads to change in erosion peak behavior from lower angles of 30° to around 45°. This constitutes a transition of erosion mechanism from ductile to semi-ductile behavior. This transition may be attributed to the coating formulation as well as testing conditions. In fact, at other parameter combinations, erosion behavior of coated samples remains unchanged compared to uncoated GFRP.
Biography:
Professor Nabil El-Tayeb gained his PhD from Leeds University in Leeds, UK (1986), attended his MSc at Aston University in Birmingham, UK (1982), and received his first degree “BSc” distinction with honor from Helwan University-Cairo (1977). He has over 170 international and National Publications: 85 Research Publications in the International journals of: Wear, Tribology International, Proc. IMechE Part J: J. Engineering Tribology, Materials Processing Technology, Materials & Design, Tribology online, Tribology Letter, International Polymer Processing, Tribology Transaction, Applied Composite Materials, Lubrication Science, Machining Science and Technology, Applied sciences, American Journal of Applied Sciences, Surface Review and Letters.
National University of Sciences and Technology, Pakistan
Due to its toxicity, destruction of H2S gas has been an important topic of researchers. Many studies have been carried for investigating various techniques for the removal of this gas. One of those techniques is catalytic and photocatalytic destruction of H2S gas using various catalysts including TiO2 owing to its significant potential for degradation of various pollutants. This study investigates the destruction potential of Zr doped TiO2 for the abatement of H2S gas. The catalysts were characterized using different techniques like XRD, SEM, XRF. The catalytic experiments were performed using fixed bed catalyst system. The samples were analyzed using GC-MC technique and it was revealed that the Zr doping of TiO2 did not favour positively towards enhancing the H2S destruction potential as found in other studies.
Biography:
Dr. Naeem Shahzadʼs research focused on the Environmental applications of Nanotechnology for the abatement of air pollution. He completed his PhD focusing on the destruction of H2S gas using TiO2 nanomaterials. Besides, he also validated his experimental results through theoretical modeling using Density Functional Theory (DFT) Studies. He used DFT calculations for studying different adsorption and dissociation mechanism of H2S on the surface of TiO2. He has numerous International publications in reputed journals.
Firat University, Department of Physics, Turkey
Shape memory alloys have a peculiar property to return to a previously defined shape or dimension when they are subjected to variation of temperature. These alloys recover original shape on heating after deformation in low temperature product phase condition. Shape memory effect is facilitated by martensitic transformation governed by changes in the crystalline structure of the material, and shape memory properties are intimately related to the microstructures of the alloy. Thermal induced martensite occurs as multivariant martensite in self-accommodating manner on cooling from high temperature parent phase region, and this martensite is called self-accommodated martensite or multivariant martensite. Deformation of shape memory alloys in martensitic state proceeds through a martensite variant reorientation.
Martensitic transformations occur with cooperative movement of atoms by means of lattice invariant shears on a {110} - type plane of austenite matrix which is basal plane of martensite. The lattice invariant shears occurs, in two opposite directions, <110 > -type directions on the {110}-type basal plane. This kind of shear can be called as {110}<110> - type mode, and possible 24 martensite variants occur.
Martensitic transformation is a shear-dominant solid-state phase transformation, by which the ordered parent phase structures turn into complex layered structures. Martensitic structures occur as martensite variants in a self-accommodating manner through twinning Shape memory properties are intimately related to the microstructures of the material, especially orientation relationship between the various martensite variants. Twinning and detwinning processes can be considered as elementary processes activated during the transformation. In particular, the detwinning is essential as well as martensitic transformation in reversible shape memory effect. By applying external stress, the martensitic variants are forced to reorient into a single variant leading inelastic strains. Deformation of shape memory alloys in martensitic state proceeds through a martensite variant reorientation of twins.
Copper based alloys exhibit this property in metastable β-phase region, which has bcc-based structures at high temperature parent phase field, and these structures martensitically turn into layered complex structures with lattice twinning following two ordered reactions on cooling.
In the present contribution, x-ray diffraction and transmission electron microscopy (TEM) studies were carried out on two copper based alloys which have the chemical compositions in weight; Cu-26.1%Zn 4%Al and Cu-11%Al-6%Mn. X-ray diffraction profiles and electron diffraction patterns reveal that both alloys exhibit super lattice reflections inherited from parent phase due to the displacive character of martensitic transformation.
Keywords: Shape memory effect, martensitic transformation, self-accommodation, twinning and detwinning, layered structures.
Laboratoire de Physique des Rayonnements, Departement de Physique, Faculty des Sciences, University de Annaba, Algeria
We present the results of density functional calculations to study the electronic structures and the effective masses for II-VI zinc-blende wide band gap semiconductor compounds by computing the curvature of the principal band extrema at the Γ point. We also calculated the optical properties of the technologically important, using the full potential linearized augmented plane wave method within the (GGA) approximation. Our calculations were performed to evaluate the dielectric function (realand imaginary parts), and the loss function of the II–VI semiconductors. Also the refractive index and the extinction coefficient are all studied. Detailed comparisions are made with published experimental and theoretical data and show generally good agreement. The present results regarding the studied quantities are predictions and may serve as reference for experimental work.
Keywords: FP-LAPW, DFT, cadmium chalcogenides, effective masses, optical properties.
Department of Manufacturing and Civil Engineering, Norwegian University of Science and Technology, Norway
Selective Laser Melting (SLM) is one of the additive manufacturing processes, which can produce a three dimensional part from a pre-designed computer aided design (CAD) data layer by layer. The major advantage of the SLM process is the added functionality the parts can have apart from design flexibilities. Moreover, a near net shaped component can be produced in a single step (theoretically) and the powder particles (raw materials) can be recycled without much wastage of material and is an environmental friendly process. Extensive research has been carried out in the last decade, focusing on the development of the process parameters for different classes of materials followed by the microstructure evaluation and the testing of their mechanical properties. Some studies has also focused on the mechanisms involved in the process and the laser metal interactions. In addition, researchers have also focused on the modelling aspects of the SLM process, right from the melt pool modelling, microstructural modelling, estimation of mechanical properties etc. The present talk will focus on the different classes of materials that can by fabricated by SLM. So lights will also be shed on the considerations that are taken into account in fabrication of exotic materials.
Biography:
Dr.-Ing. Prashanth Konda Gokuldoss working as an Associate Professor in Additive Manufacturing at the Department of Manufacturing and Civil Engineering, Norwegian University of Science and Technology, Gjovik, Norway. He has several years of research and industrial experience with nearly 70 research articles in peer scientific reviewed international journals. In addition, He has delivered 3 keynote lectures, nearly 15 invited presentations and over 25 contributed oral and poster presentations at various national and international Conferences, Symposiums and Seminars.
1Department of Chemistry, Adamawa State University, Nigeria
2Department of Chemistry, University of Maiduguri, Nigeria
Milk is an essential nutritional substance required for growth and development as well as food supplement to humans and animals. However, milk and milk products are considered as an important source of dietary minerals for consumers. Fresh cow milk were randomly collected from two different locations, KasuwaShanu and Bulumkutu Kasuwa within Maiduguri metropolis of BornoState, Nigeria. In this present study the concentration of the micro and macro elements (Na, Ca, Mg, Zn, Cu and Mn) was quantitatively determined using Atomic Absorption Spectrometry (AAS), while the biochemical constituents, fat and protein in the fresh cow milk were analyzed using the standard methods. The results showed milk sample C and D from BulumkutuKasuwa with highest sodium content (49.06±0.02 and 41.01±0.01 Mg/L) respectively, while KasuwaShanu samples A and B has the lowest (36.27±0.09 and 31.61±1.05 Mg/L) respectively. Calcium levels were highest (2.15±0.05Mg/L) in sample B, followed by (1.81±0.01 Mg/L) in sample D and lower (1.48±0.03 Mg/L and 1.40±0.09 Mg/L)in samplesC and A respectively. Mg, Zn, Cu and Mn were detected in all the fresh cow milk samples from the two locations KasuwanShanu and BulumkutuKasuwa and their concentrations were within NAFDAC (National Agency for Food and Drugs Administration Control) Standard values. The biochemical constituents; Protein content ranges from (7.11±0.11 to 6.32±0.03%) in samples A and B respectively of KasuwanShanu and (7.57±0.16 to 6.33±0.11%) in samples C and D respectively of BulumkutuKasuwa. The highest protein content was recorded in sample C of BulumkutuKasuwa and the lowest was recorded in samples B and D respectively. The fat levels ranges from (8.46±0.05% to 1.36±0.08%) in samples A and B respectively of KasuwanShanu and (4.57±1.00% to 3.55±0.13%) in C and D respectively of BulumkutuKasuwa. From the results it was observed that significant difference existed in protein and fat values while there is no significant difference in the values of micro and macro elements of thecow milk samples from the studied locations. However, the protein contents in the cow milk samples are significantly higher than the NAFDAC standard values but are within the maximum permissible standard limit. The high fat content in sample A is a source of worry and necessitates further monitoring in other areas and some caution in the rampant consumption of such milk.
Keywords: Micro and Macro elements, biochemical parameters, fresh cow milk, Maiduguri and Nigeria.
Department of Mechanical Engineering, Aligarh Muslim University, India
Aluminium Composites has wide application in Automobile such as design of four wheeler rim, aerospace, sports, Machines etc. the problem associated with Aluminium alloy is their low wear resistance during machining therefore an attempt is made to improve the wear properties of pure Aluminium by reinforcing it with hybrid ceramic such as SiC-B4C. In this research pure Al and Al with hybrid reinforcement of SiC-B4C are fabricated using powder metallurgy technique. 10 billets i.e. Pure Al, Al-3wt%SiC7wt%B4C, Al-5wt%SiC5wt%B4C and Al-7wt%SiC3wt%B4C are compacted with compaction loads of 3, 4 and 5 Ton and then Sintered near the melting point. Physical properties such as density, porosity, XRD and wear properties are calculated. On progressive addition of SiC-B4C, significant enhancement in physical and wear properties are obtained. Effect of Compaction load on wear property is also illustrated in this research.
Keywords: Metal Matrix Composite (MMC), green density, sintered density and P.M
Biography:
Saif Wakeel feels proud to pursue Final year Mechanical engineering from Aligarh Muslim University, Aligarh, India. Recently he has written a Book
“Fabrication and Mechanical properties of Aluminium Composites”. He has successfully completed his internship from National University of Singapore, in specific area of Nanomaterials.
1Sorbonne University, UPMC Univ Paris 06, CNRS, Laboratoire Interfaces et Systemes Electrochimiques, France
2UTC, TIMR, rue Roger Coutolenc, France
Poly Propylene (PP) powders are used for various purposes. However, its good mechanical properties are accompanied by poor wettability. The PP powder was therefore modified by a pulsed arc atmospheric pressure plasma jet (APPJ) in a homemade Wurster fluidized bed reactor (Wurster-FBR). The physical and chemical modifications of the treated PP powders as compared to the nontreated ones were determined by water contact angle (WCA) measurements, X-ray photoelectron spectroscopy (XPS), attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR) and SEM for morphology observations.
The average diameter of our PP powders being determined to be 700 μm, they can be classified as particles of category B according to Geldart classification which can be easily fluidized.
The plasma torch was introduced into transparent glass reactor with 118mm insidediameter, placed in the middle of a bronze gas distributor. An internal Wurster tube was added to control the residence time of particles in the plasma jet, and therefore the homogeneity of the treatments. The innovative design of wurster tube improved the powders treatment process by increasing the interaction between plasma torch and the particles, therefor the efficiency of system increased.
A 2D CFD model was developed using Comsol Multiphysics 5.2 along with this experimental study. The multiphase flow was calculated by using the k-e turbulent Euler-Euler model which solves one set of Navier-Stokes equations per phase to accurately describe theparticles velocity and volume fraction inside the reactor.
Keywords: Atmospheric-Pressure Plasma Jet, Fluidized Bed Reactor, Wurster Reactor.
Department of Chemical and Environmental Engineering, Yale University, USA
Analogues to thin-film solar photovoltaics (PV), a typical solar-fuel device consists of a hybrid inorganic-polymer composite that directly converts solar energy into H2 or liquid fuels, with inputs of sunlight, water and CO2 only. Once abundant and low-cost solar H2 is produced as a universal energy carrier, we can use it to convert synthetic or bio-fuels, upgrade petrochemical feedstock, improve combustion and produce ammonia. However, achieving such an efficient and flexible solar-fuel membrane is not trivial, particularly due to the instability of efficient semiconductor/liquid interfaces.
In this talk, I will first discuss several key advances of protective coatings as a stabilization strategy. All technologically important semiconductors so far like Si and GaAs photocorrode. Although protective coatings are not prevalent in solid-state research, they are essential in the field of photoelectrochemistry. With protective coating strategies, a 10% efficient water-splitting prototype has been demonstrated. With modeling-inspired materials design, I will show a viable pathway beyond 20% efficiencies. Finally, I will discuss neededunderstanding of photocatalytic processes at solid/liquid interfaces. A membrane-less photocatalyst design and its novel photochemistry promises efficient and low-cost solar-to-liquid fuel production.
Biography:
Shu Hu is an Assistant Professor of Chemical & Environmental Engineering at Yale University. He is also affiliated with the Energy Science Institute at Yale West Campus. Shu Hu graduated from Tsinghua University in 2006 and received his PhD degree of Materials Science and Engineering in 2011 from Stanford University, where he worked on nanoscale germanium-silicon crystal growth and epitaxy control. He was then a postdoctoral scholar at California Institute of Technology and Joint Center for Artificial Photosynthesis. His work spans fundamental and applied research areas in nanophotonics, nanoscale group III-V growth and solid-electrolyte interfaces for artificial photosynthesis. The experimental demonstration of protective coatings was highlighted in major media including NPR News, Scientific American, CE&N News, and Nature.
Department of Biology, Chemistry, & Environmental Sciences. American University of Sharjah, United Arab Emirates
Several synthetic approaches were used to obtain nano-sized porous and monoclinic WO3 (m-WO3) powders. All of these methods begin with a standard preparative method where H2WO4 is first generated by passing a Na2WO4 solution through a cation-exchange resin. It is shown that high surface area particles are produced by dripping the H2WO4 exiting from the ion exchange column into a solution containing oxalate and acetate exchange ligands or alternatively, into a water-in-oil (w/o) based emulsion. The porous WO3 powders were prepared using a standard synthetic method for MCM 41. The surface properties were investigated by the water desorption isotherm, the pyridine adsorption, and the adsorption properties of dimethyl methyl phosphonate (DMMP) that are monitored by FTIR spectroscopy. The adsorption properties was found to depend on the initial evacuation temperature of the WO3 surface as this alters the relative number of the Lewis and Brønsted acid sites along with the amount of adsorbed water. Tailoring the architecture of WO3 powders leads to a new size selective approach to improving selectivity in semiconducting metal oxides (SMO) sensors. The key for achieving high selectivity is based on using a dual sensor configuration where the response on a porous WO3 powder sensor was compared to the response on a nonporous WO3 powder sensor. Detection selectivity between methanol and dimethyl methyl phosphonate (DMMP) is obtained because the access of a gas molecule in the interior pore structure of WO3 is size dependent leading to a size dependant magnitude change in the conductivity of SMO sensor.
Biography:
Sofian Kanan received his B.Sc. and M.Sc. degrees from Yarmouk University in 1989 and 1991, respectively. He earned his Ph.D. in Inorganic &
Material Chemistry from the University of Maine in 2000 and he worked as a Research Associate at the Laboratory for Surface Science & Technology (LASST), University of Maine for two years. He also worked as a Senior Scientist at Sensor Research and Development Corporation (SRD-Corp.) for one year. In 2003, he started his academic career as an Assistant Professor at the American University of Sharjah (AUS) where he was promoted early to the rank of Professor of Chemistry in 2012. Prof. Kanan has received a number of awards and grants for his teaching and research activities. He is an Editorial Board Member of Scientific Reports, Research on Chemical Intermediates, and Cogent Environmental Science Journals. His research interests fall under the general umbrella of developing material properties through the use of surface chemistry. Specifically, Dr. Kananʼs work is centered on the development and use of different spectroscopic techniques to probe reactions at the solid/liquid and solid/gas interface. The primary goal of his research is to obtain an understanding of the relationship between the molecular surface chemistry and macroscopic properties of materials.
1Dept. of Engineering, Bahria University, Pakistan
2Dept. of Engineering and Mathematics, University of Wolverhampton, UK
Much of the development of Metal Matrix Composites has been on monolithic lightweight alloys having inadequate fatigue resistance for many demanding applications. The use of a high stiffness ceramic reinforcement in particulate form, such as SiC, can result in a substantial increase in fatigue resistance while maintaining cost at an acceptable level. The fatigue resistance of particulate MMCs depends on a variety of factors, including reinforcement particle volume fraction, particle size, matrix microstructure, the presence of inclusions or defects that arise from processing, and testing environment. In this research the effect of these factors on the fatigue behaviour of particle reinforced MMCs is looked at while concentrating on stress versus cycles (S-N) fatigue behaviour. A unit cell model is used for simulation in ANSYS.
Keywords: Micromechanics, Fatigue Analysis, MMCʼs, Particulate, Unit Cell
Biography:
Dr. Syed Asim Ali Shah has completed his PhD from Sheffield Hallam University, United Kingdom. He specializes in Simullation and Modelling and is currently serving as a Senior Assistant Professor at Bahria University, Islamabad, Pakistan. He has published more than 25 papers in reputed national and international Journals and Confrences and has been serving as an editorial board member of repute. He is also a member of the National Think Tank for Robotics for Pakistan.
1Laboratoire de Photonique dʼAngers, Université dʼAngers, France
2Laboratoire dʼélectronique et de microelectronique (EμE), Faculty Des Sciences de Monastir, University de Monastir, Tunisia
The properties of an amorphous material to the limits (e.g. adjacent a surface) are greatly modified by the presence of the interface. For this study we use computer simulations, molecular dynamics. This technique, widely used for the study of amorphous materials, to simulate the static and dynamic properties of these environments (Allen et al.,1989). We used modified boundary conditions and we will study various statistical quantities characterizing the material derived from the numerical results. We studied the finite size effects(Burkhard et al.,2002) on a system composed of a photochromic molecular motor and a variable number of surrounding molecules Decreasing the size of the box has several effects, one of which is to increase the concentration of molecular motors in the medium due to periodic boundary conditions. Our simulations show that the diffusion coefficient D increases linearly with the concentration of chromophores when the size of the boxes decreases, but, in contrast, D decreases and remains constant in the vicinity of the chromophore. Natural cooperativity of the medium evolves with the size of the system considered. However, we note that this cooperativity is strongly modified by the action of molecular motors. Simultaneously, the dynamic behaviors caused by the finite size are also changed. However the structure of the medium is not changed by the system size.
These results show that one can increase the number of chromophore for applications in the concentrations of the study, without saturation effects. They also show that cooperative processes involved are modified by the action of the molecular motor.
Keywords: amorphous material, finite size effects, silica-based biomaterials, photochromic molecular motor, chromophore, cooperativity, supercooled, solicitation.
References:
Burkhard, D., Andreas, H., (2002), Finite size effects in a supercooled liquid, arXiv:cond-mat, 0210121v1.
Allen, M.P., Tildesley, D.J. (1989) Computer simulation of liquids, Oxford science publications.
Korea Institute of Ceramic Engineering & Technology (KICET), South Korea
Nano-structured surfaces, such as supported nano-wires, nano-tubes, nano-rods, nano-sheets, or nano metal particles have considerable potential to solve several key challenges which catalysis and renewable energy are currently facing, provided that their morphology and hence catalytic activity can be controlled during preparation but also during operation. In particular, the use of nanoparticles in solid oxide electrochemical cells has been considered problematic because the nano-structured surface typically prepared by deposition techniques may easily coarsen and thus deactivate, especially when used in high temperature redox conditions. Recently we have shown that perovskite lattice defects in general and built-in A-site vacancies in particular, are instrumental for tailoring several aspects related to exsolution, including particle nucleation, size, distribution, stronger interaction with the parent support, and can also enable a wider range of species to be ex-solved more reliably, including for instance, Ni (1).
Here we show that robust transition metal nano complex grown in situ from specifically designed nonstoichiometric perovskites or extreme nano ceria share a uniquely strong interaction with the parent support and form a well-functioning solid oxide electrolysis cell cathode, with good stability even after several redox cycles. In this study, it will be therefore concluded that novel method for robust ceramic electrode with nano complex could be used as an active cathode in solid oxide electrolysis with excellent redox and coking tolerance.
Biography:
Dr. Tae Ho Shin (Tim. J. Shin) is an academic researcher of Energy Materials Centre at Korea Institute of Ceramic Engineering & Technology (KICET), South Korea. He received M.S. in ceramic engineering from Yonsei University and his PhD in advanced materials chemistry from Prof. Tatsumi Ishihara at Kyushu University (PhD 2012), Japan. He held a research fellow position, followed by University of St Andrews Research Fellowship (2012-2015) and worked with Prof. John T. S. Irvine. After fellowship work, he joined the faculty of Energy Materials Centre at KICET, Korea. His research involves developing new oxide electrode for the electrochemical devices such as SOFC and SOEC. An area of particular interest is crystal structure analysis for understanding and predicting the design of materials with targeted electrochemical properties. Recently, he received the Reaxys PhD Prize Finalist Award (2012), Dr. Bernard S. Baker Student Awards for Fuel Cell Research (2011, FCS&E USA), and the Electrochemical Society (USA)ʼs Summer Fellowship Award (2011).
Institute of Chemical Materials, China Academy of Engineering Physics, China
Transparent conductive films (TCFs) is high transparency in visible light (λ=380~780nm) with nearly metallic conductivity. They are important materials in functional films because of good conductivity and optical transmittance. In this study, we incorporated Nafion® into the coating layer of carbon nanotubes (CNTs) to improve the transparent conductive films. The transparency and electrical conductivity properties of the CNTs/Nafion® thin films were significantly improved by the 3,4-ethylenedioxythiophene (EDOT) incorporation. Carbon nanotubes/Nafion® (CNTs/Nafion®) composites are prepared based on filtration technology. CNTs are dispersed in mixed with different amounts of Nafion® and then driven by ultrasonic. From these mixtures CNTs/Nafion® composites were dipped in EDOT. The dispersion of CNTs/Nafion® is characterized by infrared spectroscopy, scanning electron microscopy and UV–vis spectra. Using the developed process, CNTs/Nafion® thin films that are uniform and the dispersion of CNTs with Nafion® connected with one another to form an interweaving films and highly transparent have been fabricated. The resistivity and optical transmittance of CNTs/Nafion® with EDOT thin film were 82 KΩ/□ and over 69% with optimum condition when the volume of CNTs/Nafion® was 0.3mL and the ratio of Nafion® was 2.5%. With the optimization of the composition of Nafion® composite, CNTs/ Nafion® thin films might potentially offer better or comparable performances as the conductive oxides.
King Abdullah University of Science and Technology (KAUST), Saudi Arabia
Silicene is the Si analogue of graphene with the same honeycomb structure and linear dispersions of the π and π* bands at the K point of the Brillouin zone. It is predicted to realize a buckled structure, due to sp2-sp3 hybridization, and is compatible with the current Si-based nano-electronics. Silicene yet has not been achieved by mechanical exfoliation but can be deposited on metallic substrates such as Ag (111), Ir (111), and ZrB2 (0001). Regrettably, strong interaction to these substrates destroys the Dirac physics. For this reason, semiconducting substrates, including Si (111) and SiC (0001), have been explored theoretically to evaluate whether they lead to a Dirac cone with reasonable band gap (which is essential for applications). However, surface passivation is inevitable for these and similar substrates, due to their dangling bonds. Layered materials such as MgBr2 (0001), MoX2, and GaX2 (X = S, Se, and Te), on the other hand, might preserve the characteristic electronic states of silicene and additionally simplify the preparation procedure as passivation is not required. The predicted effects of different substrates on silicene will be compared and evaluated with respect to technological requirements.
Biography:
Udo Schwingenschlögl is a Professor of Materials Science & Engineering at King Abdullah University of Science and Technology (KAUST). His research interests in condensed matter physics and first-principles materials modeling focus on two-dimensional materials, interface and defect physics, correlated materials, thermoelectric materials, metal-ion batteries, nanoparticles, and quantum transport.
China Academy of Engineering Physics, China
An efficient hydrophobic condensation strategy was presented to develop3D hierarchical Ag-nanosheet micron/nano-pillar arrays (AMA) surface-enhanced Raman scattering (SERS) spectroscopy sensors for the ultrasensitive detection of diluted water soluble organicmolecules. Highly uniform Si micro-pillar arrays which had the similar modality as cicada wings were prepared by a photolithographic technique and deep-Si etching process and then used as templates for the electrochemical deposition generation of 3D hierarchical AMA with biomimetic superhydrophobicsurface. For the first time, we reported the use of such AMA SERS platform to detect various organic pollutants (R6G, explosives picric acid, NTO, FOX-7) based on this working principle. Through a simple synthetically processing, NTO, and FOX-7 were synthesized as water-soluble salt K+(NTO)- and K+(FOX-7)-. When solution was dropped to the biomimetic superhydrophobic substrate, the greatly diluted solute was concentrated and localized into a very small region of the plane, where plasmonic electric-field hot spots were used to carry out molecule detection. So few molecules could be localized and detected even at femto-(10-15mol/L of aqueous R6G) levels without solution wasting in a short time. Contrastively, R6G was detected only at 10-12mol/L levels in ethanol. The integration of water-soluble synthesis of low-solubility molecules and the hydrophobic condensation strategy dealing with the problems for limited organic solutions of target molecules in difficulty to SERS sensing were achieved.
Diodes Inc., USA
ZnO thin film transistors (TFTs), due tohigh electron mobility and visibletransparency, has been used as an alternative to amorphous silicon TFTs for use in flat panel displays. ZnO is also an industries fabrication friendly material because of lower deposition temperatures than polycrystalline siliconanda higher mobility than amorphous silicon. The purpose of this talk will focus on ZnO thin film fabrications in two systems: Atomic layer depositions (ALDs) and solution based fabrications. Based on my research result a detailed analyze is displayed for this two different fabrication systems. Two different applicationsbased on refreshing rate, head up devices (HUDs) and portable artificial reality (p-AR), are explained. Challenges and solutions of ZnO thin film deposition in nowadays manufacturing industries are also included in this talk.
Biography:
Dr. Yang Xi graduated from The University of Texas at Dallas in 2015 as Ph.D. in materials science and engineering. During his Ph.D. study he focused on 2D-semiconductor fabrication and devices design. Also his research covered low-k organic materials, PVDF fibers, nanomaterials and porous materials. Dr. Yang Xi is working in Diodes Inc., (NASDAQ: DIOD) for semiconductor fabrication system quality design and new devices failure analysis.
Ethiopia biotechnology institute, Ethiopia
In this comparative study, the effect of low density poly ethylene and ethylene vinyl acetate loading ratio by melt blending with additives and without additives on mechanical properties for prosthetic and orthotic application was analyzed. To carry out this thermoplastic materials such as low density poly ethylene (LDPE), Ethylene vinyl acetate (EVA), color pigment, calcium carbonate, titanium dioxide and black carbon have been used as raw material to produce the sample in sheet form and to achieve comfortable prosthetic and orthotic application. The method used were blending, molding, testing of produced materials. Increasing the content of EVA and decreasing content of LDPE had effect on compatibility, tensile strength and elongation at break vice versa. The blended composite with additives have no significant effect on molding and without additive have significant effect on molding due to molecular mobility which leads shrinkage. The maximum tensile strength reached to 10.5Mpa and minimum tensile strength reached 2.8Mpa and the maximum elongation at break reached 469.8% and minimum elongation at break 40.2%. The other result are in between of these ranges, which have better than existing one has maximum tensile strength of 2.3Mpa and elongation at break have 265%. The mean value of maximum tear load is 74.4N/mm and minimum tear load have 38.9N/mm which have better result than existing one has 10.5N/mm. Scanning electron microscope(SEM) test result showed that specimen with more filler and less content of EVA become poor in its morphology and compatibility.
Keywords: Prosthetic, orthotic, ethylene vinyl acetate, low density poly ethylene
Biography:
Yenealem yilma has completed his Masters at the age of 28 years from Hawassa University. He is the Team ledear of Ethiopia biotechnology institute Material Science department biomaterial research group.
Dept. of Materials Science and Engineering, Chonnam National University, Korea
When an average stress in growing metallic thin film was measured as a function of the film thickness during real time deposition, a reversible stress shift to the tensile side was observed for Al, Cr, and Cu thin films due to an abrupt interruption of deposition. This study comprised the effects of metal mobility and final grain size on the magnitude of the stress shift caused by an abrupt interruption of thin film deposition. The reversible shift was observed only for the interruptions at the compressive stress state. For Al the total amount of stress shift increased as the magnitude of compressive stress at the point of interruption increased. The amount of stress shift increased as the grain size of film before the deposition interruption was larger for Cu.
Keywords: Thin Film, Stress, Mobility, Grain Size.
Unversity des Siences et de la Technology Houari Boumediene, Algeria
We determined the crystalline characteristics of the phases α* titanium and TiCyOx under vacuum and carbon monoxide pressure by in situ X-rays diffraction.
We show that the structure of the metal is stabilized by insertion of oxygen atoms in its octahedral holes. ¶ This phase leads by oxidation to lacunar titanium monocarboxide NaCl–type structure which is not decarbonized to reform metal as it is the case for niobium and tantalum.
Publications
1. Journal of Alloys and Compounds, 210 (1994) 201-208.
2. Journal of Alloys and Compounds, 288 (1999) 124-140.
3. Compte Rendu de lʼAcad. Sciences, Paris, IIb,320 (1995)
4. Journal de la Society Algerienne de Chimie (1994) 4
5. Journal de la Society Algerienne de Chimie (1997) 7
6. Annales de chimie-Science des Materiaux, Vol 31(5)(2006)
7. Annales de chimie-Science des Matériaux, Vol 33(1)(2008)
8. Journal of Alloys and Compounds, 654 (2016) 509-513.
Communications Internationales
1. 4° Colloque Franco-libanais sur la science des materiaux (Mai 2004) Beyrouth – Liban
2. The fifth Jordanian International Conference of Chemistry. Organisé par lʼuniversity de Yarmouk (Jordanie) Juin 2008.
3. Advances in Materials and Prrocessing Technologies (AMPT 2008). Organise par lʼArabian Gulf University of Bahrein. Novembre 2008.
4. Global Conference on Global Warming. Organise par lʼuniversity des Sciences dʼIstanbul du 05 au 09 Juillet 2009.
5. Septieme Conference Internationale sur la Science des Materiaux. Organise par lʼUniversity Libanaise, Beyrouth du 20 au 22 Mai 2010.
6. (4°International Meeting on Molecular Chemistry) Organise par lʼuniversity Sultan Moulay Slimane RICMD4. Marrakech du 25 au 26 Novembre 2010.
7. 4th International Chemistry Conference, organise par lʼuniversity Roi Saoud de Ryadh, du 190au 21 Novembre 2011.
Department of Physics, University of Saida, Algeria
Based on the full-potential linearized augmented plane waves method (FL-LAPW) with local density approximation (LDA), the partials and totals densities of state of T l3SbS3 and SbT eI are calculated in order to find the semiconductor character via direct or indirect gap. T l3SbS3 and SbT eI presents the most important candidates of the antimony chalcogenides family. Their densities of states curves bring out characteristic features in the valence band a core like peak, at environ 13.00 eV below the valence band maximum, originating mainly from S 3s and I 5s states respectively, and a three-peak structure at the top of the valence band from S 3p and I 5p states hybridized with Sb 5p and Te 5p states. Our results give a good agreement with other theoretical calculations and experimental data.
Keywords: The full linearized augmented plane wave method (FL-LAPW); Density functional theory (DFT); The local density approximation (LDA); Kohn Sham orbitals (KSO).
PACS numbers: 23.40.-s, 26.30.-k, 21.10.Re.
1Laboratoire dʼetude des materiaux (LEM), University de Jijel, Algeria
2Laboratoire des Essais Non Destructif par ultrason (LEND), University de Jijel, Algeria
This work presents a novel approach for preparation the oxygen deficient LaBaCaCu3Oy compound (La1113): temperature and duration optimization when applying the nitrate decomposition method. The XRD results reveal the presence of triple perovskite structure LaBaCaCu3Oy as a dominant phase crystallizing in the tetragonal system of the space group P4/mmm (a = 3.873(7) A°; c = 11.595(4) A°. The SEM observation shows a low porosity while EDAX data indicates the presence of the basic elements (La, Ba, Ca, Cu and O). The compound superconducting character is confirmed by AC susceptibility measurements with Tc = 63K.
Keywords: Optimization of nitrates decomposition method, X-Ray diffraction (XRD), Energy Dispersive Analysis of X-rays (EDS or EDAX), Superconductors.
University of sindh jamshoro, Pakistan
Anas platyrhynchos (Mallards) belongs to family: anatidae (vigors1820) order: Anseriformes (wagler 1838) genus Anas, species platyrhynchos.
Mallard is the most recognized waterfowl in the world with typical duck shaped body. Anas platyrhynchos is distributed to these regions of the world: Australian region, Ethiopian region, Nearctic region, Neotropical region, oriental region, pale arctic region and oceanic region –animal diversity web.
These birds are hunted for food, eggs and meat and are good source of protein. They are important ornamental birds and kept for aesthetic purpose also domesticated.
Mallard was found to be an early breeder; egg laying started in the month of march and continued till June. April was found to be peak egg laying month. 15 nests were studied.
Mean egg weight was 48.27gm, while as the average egg size was 56.42 x 40.55mm (±2.34 x ±1.19). Average clutch size was found to be 8.27 (±2.23).
1School of Materials Science & Engineering, Jimma University Institute of Technology, Ethiopia
2Department of Chemistry, College of Natural & Computational Sciences, Mekelle University, Ethiopia
3School of Civil & Environmental Engineering, Jimma University Institute of Technology, Ethiopia
This paper presents surface modification of sisal (Agave Sisalana) fibers by alkalization to tune up mechanical limitations of natural fibers reinforced polymer composites associated with poor fiber-polymer matrix compatibility. Upon surface treatment, the fibers were surface coated with polyaniline through in situ oxidative polymerization to further enhance resistance to water absorption by introducing hydrophobic polymer backbone. Based on the results from spectroscopic and microscopic analyses, surface modification through alkalization is an effective approach to remove lignin and hemicellulose from the surface of sisal fibers. It also enhanced fiber-polymer matrix compatibility assured bya significant increase in tensile strength. Polyaniline deposition on the surface of sisal fibers was successful to introduce hydrophobic polymer backbone to the system to enhance resistance to water absorption thereby increasing tensile strength significantly.
Laboratory of Technology and of Solids Properties, Faculty of Sciences and Technology, BP227 Abdelhamid Ibn Badis University, Algeria This work is to study the effect of the variation of structural parameters on the band structure in the quasiperiodic Fibonacci superlattices AlxGa1-xAs/GaAs using the formalism of the transfer matrix and Airy functions [1]. Ours results show that increasing the width of Fibonacciʼs wells af allows to the confinement of subminibands with a widening of minigaps, this causes a consistent and coherent fragmentation. The barrier thickness of Fibonacci bf acts on the width of subminibands by controlling the interaction force between neighboring eigenstates. Its increase gives rise to singularly extended states. The barrier height Fibonacci Vf permit to control the degree of structural disorder in these structures [2]. The variation of these parameters permits the design of laser with modulated wavelength [3].
Keywords: Transmission coefficient – Quasiperiodic superlattices - Singularly localized and extended states - Structural parameters - Laser with modulated wavelength
[1]. Z.Aziz, S. Bentata, R. Djelti and Y. Sefir, Solid state Communication 150, 865-869 (2010).
[2]. Z.Aziz, Y. Sefir, R.Djelti, B. Bouadjemi and S. Bentata, IEEE Conference Proceeding, Electronics, Communications and Photonics Conference (SIECPC) (2013).
[3]. Yamina sefir, Zoubir Aziz, Redouan Djelti, Bouabdellah Bouadjemi, Samir Bentata, Superlattices and Microstructures, S0749-6036(13)00244-9(2013).
1Department of Chemistry, School of Physical Sciences, Central University of Kerala
2Department of Biohemistry and Molecular Biology, School of Biological Sciences, Central University of Kerala
3Laboratory Chemical Remediation Processes, Institute for Nanomaterials, Advanced Technology and Innovation (CXI), Technical University of Liberec
In the present study we report a green and eco-friendly method for the synthesis of titanium dioxide (TiO2) nanoparticles (NPs) from titanium oxysulfate solution using Gum Arabic (Acacia senegal), as reductive and NPs formation agent. The synthesized TiO2 NPs were characterized by various techniques such as XRD, FT-IR, Raman spectroscopy, SEM-EDX, TEM, HR-TEM and UV-visible spectroscopy. The average particle size was calculated as 9nm from TEM data and the synthesized NPs were found to be spherical in shape. XRD analysis confirmed the formation of TiO2 NPs in the anatase phase with high crystal purity. Furthermore, the activities of TiO2 NPs were evaluated with regard to their ability to remove organic dyes (Coomassie Brilliant Blue G-250). The nanoparticles exhibited excellent efficiency in dye removal ie., about 99.3% removal efficiency was observed. And the results of this study suggests that nano biogenic titanium dioxide material acts as a good implantable material for environmental remediation.
Keywords: Titanium dioxide nanoparticles, hydrocolloid, Gum Arabic, dye removal, green synthesis.
1University of Abomey-Calavi, Benin
2Universiy of Lorraine
In recent decades, we have been confronted with global environmental issues such as climate variations due to the increase in greenhouse gas emissions, pollution, and the degradation of the environment. These different environmental problems are due to human activities in different fields such as industry, energy, transport, construction. The construction sector is one of the main contributors to this situation as it is the largest energy consumer and the second largest CO2 emitter in the world. It is therefore important to build eco-friendly buildings, which consume little energy and emit less greenhouse gases over their entire life cycle. Hence the use of natural materials such as plants that are renewable, recyclable and sustainable. In this study we used rice husks as vegetable granules in a cement matrix to produce concrete blocks, interjoists, rice husk suspended ceilings and insulation for buildings.
Setting tests on pure cement paste formulated with water resulting from the infusionof the rice husk showed that these aggregates had no inhibiting effect on the setting of the cement. To confirm this hypothesis, a chemical analysis of the rice husk was carried out and the results showed that the extractable ratio of rice husks is almost zero, unlike other plant aggregates such as hemp and wood. Measurements of thermal conductivity have shown that rice husk concrete is a very good alternative to more conventional systems in terms of thermal insulation.
Biography:
Edem CHABI, born August 18, 1989 in Gogounou (Benin), is a young doctoral student specialized in materials and processes. He is particularly interested in the development of innovative materials with reduced environmental impact. Edem CHABI holds a Diploma in Design Engineering in Buildings and Public Works from the Polytechnic School of Abomey-Calavi (Benin) in 2012 where he developed a composite material based on wood waste (sawdust) and plastic bags to make a wood / polymer material. In 2014, after 2 years of research on plant concretes, he obtained the Diploma of Advanced Studies in Materials and Structures from the University of Abomey-Calavi. Currently, he is the third year of doctoral dissertation in cotutelle between the University of Abomey-Calavi and the University of Lorraine whose defense is scheduled for December in Nancy.
1Electronics & Nano Devices (END) Lab, Physics department, Faculty of Science, South Valley University, Egypt
2Egypt Nanotechnology Center (EGNC), Cairo University Sheikh Zayed Campus, Egypt
Nanotechnology is a multidisciplinary field, which covers a vast and diverse array of devices derived from engineering, biology, physics and chemistry. These devices include nanovectors for the targeted delivery of anticancer drugs and imaging contrast agents. Nanowires and nanocantilever arrays are among the leading approaches under development for the early detection of precancerous and malignant lesions from biological fluids. Nanotechnology is being used to make surfaces self-cleaning and stay clean for a long time. Nanotech can be found in cosmetics, sunscreens, clothing and many other consumer products today.
In the next 20 years, nano-technology will touch the life of nearly every person on the planet. The potential benefits are mind boggling and brain enhancing, but it is not without risk.
Nanotechnology poses many great challenges not only to scientists and engineers but also to society at large. Researchers in nanotechnology must do their great efforts to overcomes the challenges and reduce the risks that nanotechnology faces. So in this talk we will review the challenges that face nanotechnology and how we can overcome it.
1Faculty of Engineering, Department of Elec. Power, University of Ain Shams, Egypt
Eng. Hanan M Askaria2
2Electrical Engineer, Egyptian Electricity Transmission Company, Egypt
This paper presents control of Wind Energy Conversion Systems (WECS) based on Doubly Fed Induction Generator (DFIG). A new maximum power point tracking (MPPT) strategy based on the fuzzy logic controller was developed. At given wind velocity, the pitch compensation (pitch controller) is controlled to get the maximum power can be extracted from the turbine. The proposed control strategy that achieved via a fuzzy controller is properly tuned using genetic algorithms (GA). The effectiveness of the proposed control strategies is validated by theoretical analysis and simulation carried out using Matlab/Simulink environment.
Biography:
Maher A. El-Dessouki gained an M.Sc. degree in power systems in 1986 at Ain Shams university, Cairo, and a Ph.D. degree from Warsaw University of technology, Poland in 1994 in dynamic study of power systems considering electrical machines as dynamic loads. His research interests include modeling, simulation, control of electrical machines and PV set, power systems dynamics and stability, use of the artificial intelligent in the control of both the electrical machines and power systems. He supervised many research projects in both undergraduate and postgraduate studies. He teaches many courses of electrical machines and power system inside and outside Egypt in different universities. Now he is an associate professor in the Department of Electrical Power and Machines, Faculty of Engineering, Ain Shams University, Cairo, Egypt. He is a Senior Member of the Association of Energy engineers (AEE) in the USA. He is currently applying for Ain Shams University Prize for international publishing in 2014.
Contact us for any additional information - contact@madridge.org
Madridge Publishers is licensed under a Creative Commons Attribution 4.0 International License.