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Item Chemistry in Second Life(Springer Open, 2009-10) Lang, Andrew SID; Bradley, Jean-ClaudeThis review will focus on the current level on chemistry research, education, and visualization possible within the multi-user virtual environment of Second Life. We discuss how Second Life has been used as a platform for the interactive and collaborative visualization of data from molecules and proteins to spectra and experimental data. We then review how these visualizations can be scripted for immersive educational activities and real-life collaborative research. We also discuss the benefits of the social networking affordances of Second Life for both chemists and chemistry students.Item Chemistry Central Journal(Chemistry Central Journal, 2009-10) Lang, Andrew SID; Bradley, Jean-ClaudeThis review will focus on the current level on chemistry research, education, and visualization possible within the multi-user virtual environment of Second Life. We discuss how Second Life has been used as a platform for the interactive and collaborative visualization of data from molecules and proteins to spectra and experimental data. We then review how these visualizations can be scripted for immersive educational activities and real-life collaborative research. We also discuss the benefits of the social networking affordances of Second Life for both chemists and chemistry studentsItem Modelling of Internal Stresses in Sheet Glass during the Cooling(Scientific Research, 2011-06) Benbahouche, Saci; Roumili, Fouad; Sangleboeuf, Jean-ChristopheInternal stresses in glass are generated by interactions between thermal contraction, elasticity at low temperatures, viscoelastic flow at higher temperature, and temperature gradients caused by cooling. This work intends to work out calculation program for real temperature distribution and internals stress, and to study their behaviour during the quenching through a flat plate of soda-lime glass from different temperatures.Item Analysis of Cr Atoms Three-Dimensional Deposition Characteristics(Scientific Research, 2011-09) Yang, Hua-Lei; Zhang, Wen-Tao; Yang, JianThe semi-classical model is used to simulate the three-dimensional trajectory and deposition distribution of the chromium atoms in the Gaussian laser standing wave field using the Runge-Kutta method, and then the three-dimensional deposition stripes are also given, besides, the effects of atomic beam divergence, chromatic aberration and spherical aberration on deposition structure are also analyzed.Item Potential Application of Silica Aerogel Granules for Cleanup of Accidental Spillage of Various Organic Liquids(Scientific Research, 2011-10) Parale, Vinayak G.; Mahadik, Dinesh B.; Kavale, Mahendra S.; Rao, A. Venkateswara; Wagh, Pratap B.; Gupta, Satish C.The experimental work has been carried out to study the absorption-desorption properties of the silica aerogels, for their use in oil spill cleanup application. For these studies, silica aerogel granules were prepared by two step acid– base catalyzed sol–gel process, involving ambient pressure drying of alcogels, were made use for absorption & desorption studies of different organic liquids. The optimal molar ratio of precursors tetraethoxysilane (TEOS):Methanol (MeOH):Oxalic acid:NH4OH:NH4F:trimethylchlorosilane (TMCS) was kept constant at 1:16.5:0.71:0.58:0.60:0.98, respectively. In all, four alkanes, four aromatic compounds, four alcohols and three oils were used for absorption and desorption studies of organic liquids. The absorption capacity of aerogel sample was quantified by measuring the mass of the organic liquid absorbed by unit mass of the aerogel sample. The hydrophobic aerogel granules showed a very high uptake capacity and high rate of uptake. The desorption of solvents and oils was studied by keeping the liquid absorbed aerogel granules at various temperatures and weighing them at regular time intervals until all the absorbed liquid got totally desorbed. The Fourier transform infrared spectroscopy analysis showed that the aerogel structure was not much affected by the solvent absorption, while the oil absorption led to the shrinkage, resulting in a dense structure after desorption.Item Improving Functional Characteristics of Wool and Some Synthetic Fibres(Scientific Research, 2011-10) Allam, O. G.The present article reviews recent developments in different treatments that confer functional characteristics on wool and some synthetic fibers such as acrylic, polyamide and polyester of these functionalities mention is made of shrinkage-resistance, felt proofing, ant pilling, antimicrobial, surface properties (hydrophilic, soil -resistance, water and oil-repellency), self-cleaning, anti odor and flame retardant. The article also illustrates nanotechnology applications to improve and / or to induce some of these properties. Improvement of these properties can give the fibres an important position between the textile fibres which make them more convenient in different uses.Item Safety Knowledge of LPG Auto Drivers and LPG Tank Drivers(Scientific Research, 2011-11) Bhattacharjee, Gargi; Neogi, Susmita; Das, Sudip KumarThe paper deals with the survey about the knowledge of safety during their occupational time in the LPG auto drivers and tank drivers. A structured questionnaires was developed and used for interview on LPG auto (N = 150) and LPG tanker (N = 150) drivers. Statistical results show that there is a significant difference on auto driver’s safety knowledge without training and tanker driver’s knowledge with training at regular interval of time.Item Gallic Acid-loaded Cellulose Acetate Electrospun Nanofibers: Thermal Properties, Mechanical Properties, and Drug Release Behavior(Scientific Research, 2012-02) Phiriyawirut, Manisara; Phaechamud, ThawatchaiThe gallic acid-loaded electrospun cellulose acetate fibers were successfully prepared. The fiber containing 2.5% gallic acid was smooth surface but observed drug flake on the surface of the fiber when increasing drug content. The thermal properties, mechanical properties and drug release behavior of the fibers were investigated comparing to the corresponding films.Item Cellulose Microfibril from Banana Peels as a Nanoreinforcing Fillers for Zein Films(Scientific Research, 2012-05) Phiriyawirut, Manisara; Maniaw, ParichatCellulose microfibril (CMF) was the extraction with acid mixture from peel of Musa sapientum Linn type of banana (Kluai Nam Wa). The fibrous-shape of CMF interconnected weblike structure with the average diameter 26 nm were observed by TEM. In order to prepare zein/CMF nanocomposite films, 16 wt% zein solution was prepared by dissolved in 80% ethanol aqueous solution which contain glycerol 20% w/w. The suspension of CMF and zein solution was mixed with 0% - 5% weight fractions of solid CMF in zein matrix. The morphology of the zein films is more roughness by increased amount of cellulose microfibrils. It was found that as CMF content increase from 0 to 5 wt% results in increasing tensile strength and Young’s modulus of zein nanocomposite films. The highest strength obtains at 4 wt% CMF.Item A Novel Technique for Determination of Flow Characteristics of Blast Furnace Slag(Scientific Research, 2012-06) Dash, Supratik; Mohanty, Nachiketa; Mohanty, Upendra K.; Sarkar, SmarajitA study of flow characteristics of blast furnace slag helps determine its softening and flow (liquid-mobility) temperatures. The slag with a narrow difference between the two temperatures is termed a “Short Slag”. Its formation ensures higher rates of slag-metal reactions with the trickle of the slag soon after its formation exposing fresh mass for faster reactions, the trickling slag, creating fresh interfaces facilitating slag-metal exchanges. In the present work, a novel technique is adopted to determine the flow characteristics of blast furnace slag obtained from different industrial blast furnaces. It is seen that the results so obtained agree very closely with the values obtained from adopting conventional methods of determining the liquidus temperature using “slag atlas”. It is observed that under the range of compositions studied a high C/S ratio combined with a high MgO content in the slag is beneficial to the B.F. process as it renders a “short slag”.Item Controlled Synthesis and Characterization of Nobel Metal Nanoparticles(Scientific Research, 2012-07) Hei, Huixiao; Wang, Rui; Liu, Xiaojun; He, Long; Zhang, GuizhenIn this work, monodispersed, well-shaped platinum (3.2 - 6.4 nm), rhodium (2.4 - 5.1 nm), and palladium (3.2 - 5.3 nm) nanoparticles capped with poly(vinylpyrrolidone) (PVP) were synthesized by a polyol reduction method in an ethylene glycol solution at temperature of 190˚C. The influences of synthetic parameters on the size and morphology of the noble metal nanoparticles have been systematically investigated. The noble metal nanoparticles were characterized by means of UV-vis, laser scattering particle size distribution analysis (LSPSDA) and transmission electron microscopy (TEM). The experimental results showed that the particle size of metal nanoparticles, the morphology of which was spherical, increased with the raise of metal precursor concentration as well as the amount of PVP. The optimal molar ratio of PVP/metal and metal precursor concentration for the fabrication of Pt, Rh, and Pd nanoparticles with uniform distribution were 10 and 0.1 mM, respectively. The morphologies of the Rh nanoparticles with the size of 5.1 nm were polygons, including hexagons, pentagons, and triangles.Item Detecting Ultra-Violet Radiation by Using Titanium Dioxide Nanoparticles(Scientific Research, 2012-07) Kargan, Naser Hatefi; Aliahmad, Mousa; Azizi, SamerehIn this paper sensitivity of chemically synthesized titanium dioxide (TiO2) nanoparticles to ultra-violet (UV) radiation is investigated. For this purpose three types of ultra-violet photodetectors were fabricated, one with as-synthesized TiO2 nanoparticles, another one with TiO2 nanoparticles annealed at 600˚C, and the third one with TiO2 nanoparticles annealed at 800˚C. In each case the annealing time duration was one hour. The photodetectors were fabricated on glass slides where on them a thin layer of fluorine doped tin oxide (FTO) was deposited by spray pyrolysis. The results show that all photodetectors are sensitive to UV radiation where the photodetectors fabricated from annealed TiO2 nanoparticles are more sensitive than the photodetectors fabricated from as-synthesized TiO2 nanoparticles.Item Molecular Simulation of Ion Transport at the Water/Vapor Interface(Scientific Research, 2012-08) Dweik, Jalal; Srour, Mahmoud; Karaky, Khaled; Kobeissi, Marwan; Joumaa, Wissam; Abou-Saleh, KhalilMolecular dynamics was used to quantify the role of the size, charge and polarisability of F– , Cl– , Br– , I– and Na+ ions in their distribution in the water/vapour interface system. Our results show that the larger polarizable anions I– and Br– is attracted to the surface which is traced back to surface-modified ion hydration, while the F– was repelled from the interface and the Cl– occupied the total volume of the water slab. Moreover, by artificially increasing the ions charge, anions were localized to the center of the water slab. These results demonstrate that the effect of polarizability cannot be neglected in the transport mechanism.Item Mechanical and Thermal Properties of Chemically Modified Epoxy Resin(Scientific Research, 2012-10) Ikram, Sumeera; Munir, ArshadDiglycidyl ether of bisphenol-A (DGEBA), having number average molecular weight (Mn) 375, was modified by incorporating the hydroxyl terminated polybutadiene (HTPB) based prepolymer using isophorone diisocyanate as a coupling agent. To increase the compatibility between the epoxy resin and HTPB part, polar groups were introduced in the later to achieve physical and chemical interactions between the two phases. The finally modified DGEBA system was cured with amine based hardener. FTIR and 1 H-NMR were used to monitor the whole modification procedure. The rubber particles size and distribution was monitored as a function of HTPB contents in the resin system using scanning electron microscopy (SEM). The mechanical, thermal and thermo-mechanical properties have shown that the tensile strength, toughness, ductility and impact strength of the modified cured system have been successfully increased at some optimum HTPB contents without affecting the inherent thermal and thermo-mechanical stability associated with DGEBA resin system. Some of the mechanical properties like flexural modulus, tensile modulus and compressive strength decreased with increasing rubber contents.Item High Performance Oil Resistant Rubber(Scientific Research, 2012-10) Khalaf, A. I.; Yehia, A. A.; Ismail, M. N.; El-Sabbagh, H.Blending of polymers has gained much interest due to the fact that, it can be used to produce new polymeric materials with specific properties suitable for some special applications. The blends from acrylonitrile butadiene rubber (NBR), chloroprene rubber (CR) and polyvinyl chloride (PVC) has been designed for products working in contact with oils. The characteristics of the designed blends either binary blends (NBR/PVC or PVC/CR) or ternary blends (NBR/ PVC/CR) were investigated by rheological properties, mechanical analysis and swelling in oil and toluene. It was found that the incorporation of PVC in the blend compositions leads to the decrease in degree of swelling, the penetration rate and the average diffusion coefficient. On the other hand the ultimate tensile strength (UTS), the hardness and strain energy were increased. This was attributed to the plastic nature of PVC, beside its additional behavior as filler. The crosslinking density in the blend vulcanizates under investigations was determined by Flory-Rehner and Mooney-Rivlin [Stress/Strain] equations. The higher values of crosslinking density determined by Mooney-Rivlin can be attributed to the additional physical crosslinks (e.g. entanglements etc), beside the chemical crosslinks determined by swelling in toluene. This study showed that NBR/PVC blends are characterized with high performance oil resistant, which can be recommended to automotive industry.Item Teaching Polymer Chemistry: Revisiting the Syllabus(Scientific Research, 2012-11) Hamaide, Thierry; Holl, Yves; Fontaine, Laurent; Six, Jean-Luc; Soldera, ArmandAs anyone who has taught polymer chemistry to undergraduate students might already appreciate, we are faced with inherent difficulties in clearly communicating the subject matter due its interdisciplinary character. This paper is thus aimed at proposing a new educational plan to teach this fundamental course in order to overcome some inherent obstacles. It is especially devoted to professors in charge of teaching a first course in polymer chemistry. We intend to emphasize polymerization by beginning with the simplest chemical pathway, namely the living anionic polymerization. In addition, some pedagogical difficulties are outlined all along this paper. This novel and distinct way to teach polymer chemistry makes the students with a background in organic chemistry more equipped to face difficulties arising from the introduction of new concepts.Item Characterization and Evaluation of Antibacterial Activities of Chemically Synthesized Iron Oxide Nanoparticles(Scientific Research, 2012-12) Behera, Sudhanshu Shekhar; Patra, Jayanta Kumar; Pramanik, Krishna; Panda, Niladri; Thatoi, HrudayanathThe iron oxide nanoparticles have been synthesized in co-precipitation method using aqueous solution of ferric and ferrous ions with sodium salt. The synthesis of iron-oxide nanoparticles were validated by UV-Visible spectroscopy which showed higher peak at 370 nm as valid standard reference. An average size of iron oxide nanoparticle found by diffraction light scattering (DLS) particle size analyser, ranges approximately between 10 nm to 120 nm with mean particle size of 66 nm. The X-ray power diffraction (XRD) analysis revealed the crystallographic structure of magnetic particles. Characterization of the mean particle size and morphology of iron oxide nanoparticles confirmed that the iron oxide nanoparticles are nearly spherical and crystalline in shape. Further the antibacterial effect of iron oxide nanoparticles was evaluated against ten pathogenic bacteria which showed that the nanoparticles have moderate antibacterial activity against both Gram positive and Gram negative pathogenic bacterial strains and retains potential application in pharmaceutical and biomedical industries.Item New Method for Synthesis of Coatings of Molybdenum, Tungsten, Their Carbides and Composites(Scientific Research, 2013-04) Godbole, Rhushikesh V.; More, Mahendra A.; Gupte, Anil S.; Godbole, Vijay P.In this paper we report, for the first time, a new approach for synthesis of high quality faceted microcrystalline coatings of molybdenum (Mo), tungsten (W), their carbides and composites. These studies are carried out using Hot Filament Chemical Vapor Deposition (HF-CVD) method wherein parent materials (Mo and/or W) are taken in the form of wires (~0.5 mm dia) and are heated to a high temperature (TF ~ 1500 - 2000C), in ambient of “oxygen (O2) diluted hydrogen (H2) gas”. Due to high filament temperature (TF), a series of pyrolytic reactions take place. Firstly, the gasification of wire material (Mo and/or W) occurs in the form of its oxide. The oxide molecules reach the substrate which is kept underneath the filament assembly. Secondly, molecular hydrogen gets dissociated into atomic hydrogen and subsequently reaches the substrate to react with oxide molecules, finally leading to the precipitation of a pure metal. This method can also be used, in situ, to convert metallic coatings into their carbides and/or composites. The method offers many other attractive features, which can not be rendered by the conventional CVD/PVD methods. The results are discussed in terms of temperature induced “Red-ox” reactions.Item Investigation into Failure in Mining Wire Ropes—Effect of Crystallinity(Scientific Research, 2013-04) Devasahayam, Sheila; Sahajwalla, Veena; Sng, MichaelA range of blends of polypropylene-polyethylene are investigated for their mechanical performances. These speciality polymer blends are chemically designed to suit high modulus/high load bearing mining wire rope applications subjected to continued bending and tensile stresses and fluctuating loads and are exposed to extreme weather conditions. In this paper we study the influence of different parameters on the performance of the wire ropes: chemistry of polymer, crystallinity of the polymer matrix, and the morphology. The FTIR and SEM studies revealed that the high fraction of polypropylene in polypropylene-polyethylene matrix lead to early failure as a result of incompatibility and phase segregation and high spherulite sizes of the polymer matrix.Item Assessment of Heavy Metals Immobilization in Artificially Contaminated Soils Using Some Local Amendments(Scientific Research, 2013-07) Abdel-Kader, Noha H.; Shahin, Reda R.; Khater, Hasan A.Three alluvial soil samples with different textures were artificially polluted with chloride solutions of Cd, Pb, Co and chromate solution for Cr. The aqua-regia extracted concentration ranges in the artificially polluted soils were 1134 - 1489 mg·kg−1 for Pb, 854 - 938 mg·kg−1 for Cr, 166 - 346 mg·kg−1 for Co and 44 - 54 mg·kg−1 for Cd. The aqua-regia extracted metals were the highest in the spiked clay soil due to its high adsorption capacity. Rock phosphate (PR), limestone (LS) and Portland-cement (Cem) were mixed with the spiked soils at 1% and 2% rates (w/w) and incubated at 30 C for 2, 7, 14, 30, 60, 150 and 360 days. The extracted DTPA metals significantly decreased with different magnitudes with increasing the incubation period accompanied by increases in both pH and EC. The data showed that cement (Cem) treatment dropped the DTPA-Pb from @ 1000 to @ 400 mg·kg−1 in all the studied soils (60% decrease) in the first 2 months while it gradually decreased from 400 to 200 mg·kg−1 (20% decrease) in the next 10 months. Limestone (LS) and rock phosphate (PR) materials were relatively less effective in lowering DTPA-Pb after 12 months of incubation. The data showed also that cement (Cem) treatment was the most effective one in lowering DTPA-Cd by @ 60% as compared to the un-amended soils after 12 months of soil incubation. Extractable DTPA-Co and Cr showed consistent decreases with time down to nearly 50% of un-amended soils due to the effect of the added amendments after 12 months of incubation with superior reductions for the cement treatment in all the investigated soils. The statistical analysis confirmed that in all the studied metals and treatment, cement treatment (Cem) was significantly the most effective in lowering the DTPA extracted metals as indicated from LSD test. It was found that up to 73% and 57% of the applied Pb and Cd, respectively, were fixed by only 1% cement. However, the present study showed that from the practical and economic points of view, that 1% Cement was the best treatment to immobilize Pb and Cd from all the artificially polluted soils.