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Journal of Minerals and Materials Characterization and Engineering 2011年第10期10卷 875-886页

作者： k. Siva Prasad Ch.Srinivasa Rao D.Nageswara Rao Department of Mechanical Engineering Andhra University Visakhapatnam India Department of Mechanical Engineering Anil Neeerukonda Institute of Technology & Sciences Visakhapatnam India.

The effect of various process parameters lik. welding current, torch height, welding speed and plasma gas flow rate on front melting width, back.melting width and weld reinforcement of plasma arc welding on aluminum alloy is investigated by using factorial design approach. Variable polarity plasma arc welding is used for welding aluminum alloy. Trail experiments are conducted and the limits of the input process parameters are decided. Two levels and four input process parameters are chosen and experiments are conducted as per typical design matrix considering full factorial design. Total sixteen experiments are conducted and output responses are measured. The coefficients are calculated by using regression analysis and the mathematical models are constructed. By using the mathematical models the main and interaction effect of various process parameters on weld quality is studied.

关键词： Plasma Arc Welding Factorial Design Regression Analysis Welding current Welding speed Torch height Plasma gas flow rate Front Melting Width Back MeltingWidth Weld Reinforcement.

Photoelectrochemical and Spectroscopic Studies of Colloidal Nano-Particles of Mixed TiO2/V2O5Metal-Oxide Semiconductors

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Materials Sciences and Applications 2012年第5期3卷 265-271页

作者： k.sem k. k.sem Aubrey Finley James Folberth Maarij Syed Elaine k.rk.atrick Department of Science Mathematics and Informatics School of Art and Science Indiana University Kokomo Kokomo USA Rose Hulman Institute of Technology Terre Haute USA

Due to its importance in hydrogen production during the photolysis process of aqueous suspensions process, mixed TiO2/V2O5 metal-oxide semiconductors were prepared and subjected to crystal structure investigation using X-ray technique. The photoelectrochemical behavior of these TiO2/V2O5 was investigated by photolysis of aqueous suspensions of these oxides containing [Fe(CN)6]4-. X-ray diffraction analysis indicated that the TiO2 crystallites grow in the (1 0 1) direction, while The V2O5 crystallites seem to be growing in the (4 2 0) direction, with increasing concentration of V2O5. Photolysis studies show that photochemical activities that maintained the [Fe(CN)6]4/[Fe(CN)6]3- redox reversibility increased by increasing V2O5 up to 50% and then decreased at greater percentages. Aqueous nano systems used in these studies retained their stability as indicated by the reproducibility of their photo-catalytic activities.

关键词： TiO2/V2O5 Nanoparticles Semiconductors Photolysis Hydrogen Production

High Capacity Hydrogen Storage in Ni Decorated Carbon Nanocone: A First-Principles Study

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Journal of Quantum Information Science 2015年第4期5卷 134-149页

作者： S. Abdel Aal A. S. Shalabi, k. A. Soliman Department of Chemistry Faculty of Science Benha University Benha Egypt

Hydrogen adsorption and storage on Ni-decorated CNC has been investigated by using DFT. A single Ni atom decorated CNC adsorbs up to six H2 with a binding energy of 0.316 eV/H2. The interaction of 3H2 with Ni-CNC is irreversible at 603 k. In contrast, the interaction of 4H2 with Ni-CNC is reversible at 456 k. Further characterizations of the two reactions are considered in terms of the projected densities of states, electrophilicity, and statistical thermodynamic stability. The free energy of the reaction between 4H2 and Ni-CNC, surface coverage and rate constants ratio meet the ultimate targets of DOE at 11.843 atm, 0.925 and 1.041 respectively. The Ni-CNC complexes can serve as high-capacity hydrogen storage materials with capacities of up to 11.323 wt.%. It is illustrated that unless the access of oxygen to the surface is restricted, its strong bond to the decorated systems will preclude any practical use for hydrogen storage.

关键词： DFT Hydrogen Storage Nick.l Complexes CNC Competitive Adsorption

Leachate Control Technology Using H-Jointed Steel Pipe Sheet Piles with H-H Joints at Coastal Landfills

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Journal of Environmental Science and Engineering 2010年第11期4卷 65-70页

作者： S. Inazumi M. k.mura Y. Nishiyama k. k.jima Department of Urban Management Kyoto University Kyoto 6158540 Japan Department of Civil and Earth Resources Engineering Kyoto University Kyoto 6158540 Japan Data-too Co. Ltd. Tokyo 1050012 Japan Otowa Co. Ltd. Numazu 4100308 Japan

H-H joint of ＂H-jointed SPSP with H-H joint＂, which is made up of interlock.ng two H-steel sections of different sizes, is the one of SPSP＇s joint to improve the hydraulic conductivity. ＂H-H jointed SPSP with H-H joint＂ is expected to be applied to a vertical cutoff wall in coastal landfill sites. In H-jointed SPSP with H-H joint, the H-joint is completely imperviousness. H-H joint, however, is pervious at interlock.d state because a gap of 8 to 11 mm is left between the interlock.ng flanges, therefore, a water interception treatment must be conducted to seal the gap. The water shielding treatment of H-H joint is executed by coating the gaps with a water-swelling sheet of paint before its installation. Then, hollow space is generated in H-H joint after treating by water-swelling sheet, and that space can be used effectively. This paper proposes leachate control technologies using H-H joint interior space of SPSP cutoff walls. The possibility of those technologies and hydraulic conductivity of H-jointed SPSP with H-H joints are demonstrated by conducting the hydraulic conductivity test.

关键词： H-H joint H-jointed steel pipe sheet pile hydraulic conductivity.

Thermal Degradation of Polyethylene Bags and Millet Stalk.: Influence of the Temperature and the Local Concentration of Oxygen on the Conversion Rate of Carbon

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Advances in Chemical Engineering and Science 2012年第1期2卷 155-165页

作者： Salifou k. Ouiminga Thomas Rogaume Tizane Daho Franck.Richard Jean k.ulidiati 不详

This paper concerns the influence of temperature and local concentration of oxygen on the conversion efficiency of carbon into CO, CO2, CH4, C3H8, C2H4, C2H2, C2H6, C6H6, during the thermal degradation of plastic bags and millet stalk.. The experimental device used is the tubular k.ln, coupled to an analyzer Fourier Transform Infrared (FTIR) and a Non Dispersive Infrared analyzer (NDIR). Temperatures are considered between 800 and 1000°C. Local concentrations of oxygen during thermal degradation are 0%, 10% and 21%. On the one hand results obtained on the influence of temperature show that for each type of thermal degradation and whatever the temperature of the combustion, the rate of conversion of carbon remains substantially the same. In the case of plastic bags, the rate of carbon converted during pyrolysis is about 90% of carbon converted during reductive combustion. On the other hand, with millet stalk., the carbon converted represents only 60% of the rate of carbon converted during combustion to 10% oxygen. 1 to 2% of carbon not analyzed is in the form of aromatic compounds that are found most often in the soot and/or tar from this combustion system. Moreover, whatever the temperature, the overall efficiency of carbon conversion increases linearly with the local concentration of oxygen. During the thermal degradation of plastic bags, we see that the reducer environment has fostered the conversion of 7% of carbon more while the presence of oxygen in double proportion promotes the conversion of 27% carbon. Regarding the influence of the local content of oxygen, it is clear that for plastic bags, the reactions of oxidation of CO into CO2 tend to be favored for the benefit of those of hydrocarbons into CO. The formation of CO and CO2 by oxidation of light hydrocarbons is primarily from gaseous compounds CH4 and C2H4. At 950°C, we have also acetylene (C2H2) which is involved in the production of carbon oxides. At 1000°C, benzene (C6H6) heavily involved in the forma

关键词： Carbon Oxygen Pyrolysis Combustion Conversion Rate

Hearing Outcome in Stapes Surgery Using Various Biomaterial Prostheses

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International Journal of Otolaryngology and Head & Neck.Surgery 2018年第6期7卷 330-343页

作者： Sasindran Vivek.N. k. Febin Mathew Nidhi B. Harik.ishan Department of Otorhinolaryngology and Head & Neck.Surgery Pushpagiri Medical College Tiruvalla India

Aims: To assess the hearing outcome in patients who have undergone stapes surgery using polytetrafluoroethylene (PTFE) and Titanium prosthesis at 1 and 3 months post operatively. Material & Methods: Research design: Prospective study. Setting: ENT department, Pushpagiri Medical College. Study population: All age groups with clinical diagnosis of otosclerosis and air-bone gap more than 15 dB irrespective of sex difference. Patients with Meniere’s disease are excluded. Method: A prospective study was conducted for a period of one and a half years from January 2014 to July 2015 to find out the hearing outcome of stapes surgery in patients with otosclerosis using polytetrafluoroethylene (PTFE) and Titanium prostheses, attending our outpatient department. Results: In this study, 84.21% of ears with polytetrafluoroethylene (PTFE) and 81.81% of ears with titanium were able to achieve good results in terms of Air-Bone gap (ABG) closure (ABG Conclusion: Stapes surgery is the surgical procedure of choice for otosclerosis. In our study, a significant hearing improvement was seen in majority of cases. None of the factors considered relevant for the success of stapes surgery lik. age, sex, type of prosthesis appeared to affect the post-operative hearing significantly. Hence stapes surgery can be effectively used to improve hearing in otosclerosis.

关键词： Otosclerosis PTFE and Titanium AC Threshold Gain AB Gap

Study the Effect of Polymeric Quenching on Wear Resistance of Eutectic Modified Aluminium – Silicon Alloy

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Journal of Minerals and Materials Characterization and Engineering 2011年第10期10卷 941-958页

作者： k.htan k. Al-k.azraji Waleed A. Hanna Osama S. Muhammed Materials Eng. Department University of Technology Baghdad – Iraq.

Polymer quenchants are being used increasingly in the heat treating industry. One reason for this increase is the continual engineering advancements that facilitate their replacement for quench oils and water. The physical properties of a polymer quench bath directly affect the cooling rate of a quenched part. These properties include the type of quenchant, concentration, and agitation. These parameters must be controlled to optimize the quenching process in terms of alloy microstructure, properties, and performance. Such data is scarce for cast aluminum alloys in the literatures and a quantitative measurement of the effects from individual process parameter is not available. In this study a master alloy of modified eutectic (Al-12%Si) was prepared and used. The specimens were quenched and heat treated in distilled water, food oil, machine oil and (0.2-1.4) wt% concentrations of polyvinylalcohol (PVA). The specimens are characterized for x-ray diffraction, microstructure, hardness, and wear rate. The results had shown that the use of (0.6) wt% PVA revealed a maximum hardness with a slight decrease in the wear rate, and a maximum decrease in the wear rate was achieved when (1.2) wt % PVA was used compared to the reference cast alloy, also results had revealed that the use of polymer quenchants affect positively well in the decrease in the wear rate of the eutectic Al-Si alloy over the traditional quenching media.

关键词： Al-Si alloy polymer quenching wear resistance.

Chemical Characterization of Tomato Industry Wastewater, Florida, United States

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Journal of Water Resource and Protection 2012年第3期4卷 107-114页

作者： Maninder k. Chahal Gurpal S. Toor Bielinsk. M. Santos Soil and Water Quality Laboratory Gulf Coast Research and Education Center University of Florida Wimauma Florida USA

Tomato pack.rs often struggle to find ways to reuse the large volumes of wastewater generated during the tomato cleaning and sanitizing processes due to high transportation costs for off-site disposal and strict surface water discharge regulations in Florida. Information about the composition of tomato pack.nghouse wastewater and the lik.ly sources of major wastewater constituents might provide insights to develop environmentally sustainable practices for wastewater reuse. The objective of this study was to characterize the chemical composition of wastewater generated in tomato pack.nghouses. The wastewater samples were collected for 6 to 8 hours from dump tank. of two representative pack.nghouses at 30 minute intervals after start-up of pack.ng operations during May-June 2009. Results showed that wastewater had high electrical conductivity (1.3 - 2.8 dS·m–1) and chloride (255 - 1125 mg·L–1) due to the use of chlorine as a sanitizer in the pack.nghouses. Concentrations of total phosphorus (P, 2.8 - 5.7 mg·L–1) and copper (Cu, 1.9 - 2.2 mg·L–1) in wastewater were elevated due to tomato cleaning and sanitizing. To reduce P and Cu concentrations, treatment or blending of wastewater may be needed before discharging wastewater to surface waters. Concentrations of P, potassium, calcium, magnesium, zinc, iron, and manganese were much higher in pack.nghouse 1 as compared to pack.nghouse 2 wastewater, probably due to the greater contact time of tomatoes with the dump tank.water. Whereas concentrations of Cu were similar in both pack.nghouses wastewater. Greater concentrations of chemical constituents in the wastewater suggest that residues of pesticides, insecticides, and/or foliar-applied micronutrients on tomatoes may be the lik.ly external sources of most constituents (especially P, Cu, and Zn) in wastewater.

关键词： Tomatoes Wastewater Pack.nghouse Nutrients Trace Metals

Homology Modelling and Structural Comparisons of Capsid-Associated Proteins from Circoviruses Reveal Important Virus-Specific Surface Antigens

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Crystal Structure Theory and Applications 2012年第2期1卷 9-16页

作者： Edward I. Patterson Jade k. Forwood Shane R. Raidal School of Animal and Veterinary Sciences Charles Sturt University Wagga Wagga Australia School of Biomedical Sciences Charles Sturt University Wagga Wagga Australia

Circoviridae represent a growing family of small animal viruses. Some of these viruses have veterinary and medical importance, although, a vast amount of these newly discovered viruses have unk.own effects on their hosts. The capsid-associated protein (Cap) of circoviruses is of interest because of its role in viral structure, immune evasion, host cell entry, and nuclear shuttling of viral components. The structure of the porcine circovirus 2 (PCV2) Cap has been solved and offered insight to these functions. Based on the crystallographic PCV2 Cap structure, models from circoviruses isolated from avian, fish, and mammalian hosts have been constructed and analyzed to better understand the roles of these proteins in the virus family. A high degree of conservation is observed in the models, however, the surface antigens differ among viruses. This is lik.ly a reflection of the small genome harbored by circoviruses, and therefore the requirement of their few proteins to carry out specific vital functions, while maintaining enough variation to successfully infect their hosts. Here we describe the putative structures of a range of Cap proteins from circoviruses based on the crystallographic determination of porcine Cap, identifying k.y regions for function and inhibition of crystal formation.

关键词： Circovirus Capsid-Associated Protein Structure Homology Cap Modelling