bluuebunny/crossref_metadata_2025 huggingface dataset:
Identification of Functional Groups of Sustainable Bio-Oil Substrate and its Potential for Specialty Chemicals Source
Authors: Shawal Nasri N. , Murtala Ahmed M. , Adilah Abdul K. , Hamza Usman Dadum
Published: July 2012

This paper describes the basic analytical technique used in characterizing bio-oil into various components in terms of function groups as well as assessing its thermal behaviour. Pyrolysis, being one of the most widely used techniques in converting biomass was employed to get bio-oil from empty palm fruit bunches (EPFB).The bio-oil obtained was characterized using Fourier Transform Infrared (FTIR) while the thermal behaviour were assessed using Thermogravimetric analysis (TGA) and Differential Scanning Calometry (DSC). The results showed a great range of functional groups of phenol, alcohols, ketones, aldehydes, carboxylic acids, alkanes, alkenes and aromatic in the FTIR spectrum. The onset thermal temperature of thermal decomposition from TGA result is 32°C corresponding to about 13.4281 mg and the amount of residue was found to be 3.9969mg which shows that the bio-oil losses weight very fast; a characteristic of lighter product which strongly support combustion. The stages on DTG curve, in the degradation, which occurred at temperature range between 70-90°C, correspond to the removal of light hydrocarbons (such as aldehydes, alcohols and carboxylic acids) and moisture content in the bio-oil. The glass transition temperature, Tg, was found to be 53.63°C indicating that the bio-oil tested is less rigid and hence requires less force delivery. The characterization results indicate that the bio-oil obtained from oil palm EFB can be a potentially valuable source of fuels and chemicals feedstocks. Utilization of bio-oil for fuels and chemicals manufacture can significantly reduce or eliminate the harmful effects of fossil based products on the environment.
Investigation on Electrical Performance of Tubular Cathode for Direct Ethanol Fuel Cell
Authors: Tang Dong , Lv Hui Min , Li Chang Yuan
Published: July 2012

A new tubular cathode support for Direct Ethanol Fuel Cell (DEFC) was prepared by the gelcasting process using mesocarbon microbead(MCMB) and graphite as the main raw materials. Through the tubular cathode electrical property test, the advantages and disadvantages of cathode tube performance are studied at different graphite proportion. The results showed that when the graphite is more than 30 percent, the charge transmission ability has become extremely close. When the graphite ratio is 40 and 50 percent, the electrical performance is the best. With the graphite doping ratio of 40 percent, the electrode electrochemical reaction will have been reinforced when the temperature is high. When the air flow is 100 ml/min, the electricity capacity is better.
Electrical Conductivity and Phase Transition of Solid Oxide Fuel Cell Electrolyte La2Mo2-xTixO9-δ Ceramics
Authors: Yu Ju Mei , Chao Ming Ju , Li De Chuan , Li Ming Yu , Wu Hua , Fu Lin Jie , Chen He
Published: July 2012

A novel series of ceramic samples La2Mo2-xTixO9-δ (x = 0, 0.025, 0.05, 0.075) were prepared by solid-state reaction method. Their structures and phase transitions were studied by XRD, DSC and CTE. Their Electrical conductivities and oxygen ion transport numbers were measured by AC impedance spectroscopy at 773~1073 K and EMF at 673~1073 K, respectively. Results showed that even when x=0.075, the sample was almost pure oxygen ion conductor under the oxygen partial pressure gradient of 1.0 atm/0.21 atm, and though all the Ti-doped samples still underwent α/β structure transition, no abrupt change in the electrical conductivity was observed accompanying with the transition. They exhibited considerably higher electrical conductivity than La2Mo2O9, especially at 773~873 K and the conductivity increased with increasing x value. The value of conductivity for La2Mo1.925Ti0.075O9-δ reached 8.5×10-3 S•cm-1 at 773 K and 0.08 S•cm-1 at 1,073 K.
Analysis of Multiple Open Hot Die Forging for a General Cylinder Based on Numerical Simulation
Authors: Guo Shu Lan , Xu Xue Dong , Zhang Zhi Jun , Hu Jin Huan
Published: July 2012

Numerical simulation of the die for cylinder upsetting is done by Marc AutoForge software on base of elastic-plastic theoretical mechanical model to analyze transient temperature field, equivalent total strain field and thermal strain field. Then qualitative and quantitative relationship is found between these Factors and die-damage. A new method-Heat Exchange Balance Method is put forward to solve the cooling problems of hot -forging die by combinating with production practice , research practice and using basic theory of finite element and thermal.
Ag Behaviors of Ag-Al Alloy Annealed in Air Atmosphere
Authors: Xiong Bin , Yu Zhen Lin , Xu Gang , Miao Lei , Shi Ji Fu , Xiao Xiu Di
Published: July 2012

The Ag behaviors of Ag-Al alloy that annealed in air atmosphere have been investigated. Over 600°C, the Ag-Al2O3 composite was prepared. But over 650°C, the size of Ag particles reduced notably. With the annealing time increasing, the amount of Ag particles reduced too. This phenomenon indicated temperature and annealing time play critical roles in annealing process. We attribute the loss of Ag to evaporation. According to discussion, the process of Ag evaporation is described in detail.
Effects of pH Value on the Stress Corrosion Cracking of Super 13Cr Tubing Steel
Authors: Yao Xiao Fei , Xie Fa Qin , Wu Xiang Qing , Wang Yi Fei
Published: July 2012

Effects of pH value on the stress corrosion cracking (SCC) of super 13Cr tubing steel were investigated in 3.5% NaCl solution, that mechanics properties and fracture morphology and SCC resistance and stress corrosion cracking susceptibility index (kscc) were analyzed by slow strain rate tensile (SSRT) stress corrosion cracking experiment method and σ-ε curve and SEM. the results Effects of pH value on the stress corrosion cracking (SCC) of super 13Cr tubing steel were investigated in 3.5% NaCl solution, that mechanics properties and fracture morphology and SCC resistance and stress corrosion cracking susceptibility index (kscc) were analyzed by slow strain rate tensile (SSRT) stress corrosion cracking experiment method and σ-ε curve and SEM. the results showed that super 13Cr tubing steel has good properties of resistance stress corrosion cracking in acidic medium, effects of pH value on super13Cr tubing steel resistance stress corrosion was not very obviously in the acidic medium, with pH value decreased, super 13Cr tubing steel tensile strength decreased, elongation rate decreased, fracture area contraction ratio decreased, break time reduced, the tendency of the stress corrosion cracking increased. the stress corrosion cracking susceptibility index kσ and kε were all increasing, that increased degree of kε were obviously than kσ, effects of pH value on the plastic deformation of super 13Cr tubing steel were greater than tensile strength.
Effect of Annealing Temperature on the Transformation Temperature and Texture of Ni47Ti44Nb9 Cold-Rolled Plate
Authors: Feng Zhao Wei , Mi Xu Jun , Wang Jiang Bo , Yuan Zhi Shan , Zhou Jin
Published: July 2012

Transformation behaviors and texture of Ni47Ti44Nb9 cold-rolled plates were studied by differential scanning calorimetry and X-ray diffraction test. R phase transformation does not occur in Ni47Ti44Nb9cold-rolled plate annealed at 350°C-750°C followed by quenching into the water. Martensite transformation temperature first increases and then decreases with increment of annealing temperature, and the maximum achieves at 700°C. The heat of reverse martensite transformation increases, while hardness decreases as annealing temperature increases. The major texture of cold-rolled plate is {332} and spread from {332} to {110}. When the annealing temperature is above 600°C, the major textures are {332} and {111} recrystallization texture in secondary cold-rolled plate.
Preparation of ZnO•SrO and its Catalysis to PET Depolymerization under Microwave Irradiation
Authors: Zuo Meng Na , Zhang Wei Lu , Feng Qing Hua , Han Chun Hua , Zhang Dong
Published: July 2012

ZnO•SrO composite metal oxides were prepared via solid-state reaction and characterized by XRD. The catalysis of ZnO•SrO to PET depolymerization under microwave irradiation was studied, and the undepolymerized PET was analysed by Gel permeation chromatography(GPC). It is found that the catalytic effect of ZnO•SrO was optimum when the ratio of catalyst was 0.5%, and the rate of hydrolytic depolymerization of PET reached 93.13%. The degree of chain scission of PET depolymerization catalyzed by ZnO•SrO is deep to some extent under microwave irradiation.
Microstructure of the Dissimilar Materials TIG Welding Joint of Mg-8Li Alloy/Al Alloy
Authors: Yin Dong Song , Wang Lu Cai , Jiang Bin , Zhang Mi Lin , Mao Li He , Li Hai Tao , Zhou Hai Rui , Li Jun Gang
Published: July 2012

Microstructure of electromagnetic pulse tungstic electrode argon arc welding (EMP-TIG) welded Mg/Al dissimilar metal joint is studyed using optical microscope, scanning electron microscope, and X-ray diffraction. The results indicate that gas tungsten arc welding can provide Mg/Al joint with excellent microstructure and performance. The welding region is composed of Mg3Al2 phase, α(Mg), β(Li), and MgAl. The weld zone and the Al alloy base materials are well combined. There are massive MgAl phase dendrites in the weld area, which cause the significantly increase of hardness at weld zone. Near the Mg-8Li alloy base metal side of the weld zone, there exists a layer of 100~ 200μm equiaxed region. About 1μm Mg3Al2 reaction layer is distributed between Mg-8Li alloy base metal and the equiaxed grains. This reaction layer and the Mg-8Li alloy base metal, as well as the weld zone of equiaxed grains, have a good combination.
Experimental Study on Particle Size Distribution of Admixtures on the Strength Influence of Low Clinker Cement
Authors: Yu Bao Ying , Xu Fen Lian , Gao Yu Xin
Published: July 2012

By testing flexural and compressive strength at different ages, the influence of particle size distribution of slag and fly ash on the strength of LCC (low clinker cement) were systematically studied. The SEM (scanning electron microscope) and laser particle size analyzer were used to study the multi-component cementitious and dense-packing effects of LCC. The results show that the strength development of LCC4 with 30% clinker could completely meet the requirements of P.O 42.5R by varying the type, content or fineness of admixtures; based on a higher fly ash and lower clinker dosage, the strength development of LCC9 is also relatively good.
Preparation of the Microencapsulated Phase Change Material
Authors: Zhang Yan Lai , Luo Lei , Wu Shao Zheng , Zhang Zhao , Li Chang Qian , Li Xiu Ping
Published: July 2012

The microencapsulated phase change material is a kind of functional material with latent heat. It may be used applied heat storage and energy transport systems. Methods of the microcapsule production and four kinds of production process are introduced.
A Study on the Bond Performance Improvement of Polypropylene Macro Fibers According to the Change of Surface Area
Authors: Choi Sung Yong , Park Young Hwan , Jung Woo Tai
Published: July 2012

Fiber Reinforced Concrete (FRC) is a representative strengthening method adopted to improve the sudden brittle failure of concrete under tension and dynamic loadings and to control the generation and propagation of cracks occurring during the curing process. The strengthening performance provided by the fiber is sensitively influenced by the physical properties of the fiber itself as well as by its volume ratio but is also varying according to the difference in the bond performance at the interface between the fiber and concrete. Even if the fiber exhibits outstanding physical performance, if the bond performance does not reach similar level, the fiber will not be able to develop fully its performance. Currently, the methods improving the fiber bond performance are essentially focusing on the improvement of the mechanical bond performance by changing the longitudinal shape of the fiber such as the application of crimped and hooked fibers. A very few methods intend to improve the bond performance by increasing the bond area of the fiber itself. Therefore, this study increases the surface area of the fiber by changing its section while preserving its volume during the fabrication process, conducts tests on the bond performance between the cement paste and the fiber with changed surface area, and examines the changes in the bond performance according to the increase of the surface area.
Study on the Isothermal Crystallization Kinetics of Polyvinyl Pyrrolidone/Polyamide 6 Blends
Authors: Zhang Shi Jie , Tang Yi Wen , Yang Xin Li , Cheng Li Hua
Published: July 2012

The Avrami equation was used in the study of the isothermal crystallization kinetics of Polyvinyl pyrrolidone/Polyamide 6 Blends. The addition of PVP can hinder the PA6 crystallization process, increase the crystallization half-time and make the crystallization rate decrease. The molecular entanglements and intermolecular hydrogen bonds between PA6 and PVP chains exert some influence also.
The Preparation and Characterization of Electroless Copperplating Low- Temperature Expandable Graphite
Authors: Lin Xue Mei , Shen Jian , Zhang Shao Xiong
Published: July 2012

Copper coating was deposited on the surface of low-temperature expandable graphite (LTEG) by electroless plating method. The effects of reaction temperature, Ni2+ concentration and pH value on the copper deposited low-temperature expandable graphite (CDLTEG) were discussed. The experimental results show that reaction temperature of 65~70°C, Ni2+ concentration of 0.006mol/L~0.008mol/L and pH value of 9~10 are the ideal reaction condition for CDLTEG. X ray diffraction analysis indicates that perfect copper cladding can be coated on LTEG through chemically plating method. It is found by thermogravimetric analysis that the depositing process of copper upon LTEG is exothermic. the oxidation of copper would obviously occur when temperature is higher than 270.8 °C, so CDLTEG should be expanded to prepare its expanded outcome at a lower temperature than 270.8 °C. The 3 mm wave dynamics test makes it clear that deposited copper has an obvious improvement effect on 3mm wave attenuation performance of LTEG.
The Durability Analysis of Secondary Recycled Asphalt Mixture
Authors: Liu Yu Long , Zhao Ning , Zhao Jin
Published: July 2012

In order to solve the waste which is generated from the recycled asphalt pavement overhaul again, this paper puts forward the idea of secondary reclaimed asphalt mixture. Through analysis the performance index of secondary reclaimed asphalt mixture and with comparison the road performance of the asphalt mixture after different recycled times,we found that, as long as mixed with the right amount of regenerative agent,the road performance index of secondary recycled asphalt mixture can be recovered to the use standard. However, with the increasing of the asphalt aged times, the declining rate of road performances of reclaimed asphalt mixture are increasing.
Influence of Final Nitriding Temperature on the Preparation and the Catalytic Performance of CoMoNx/CNTs for Ammonia Decomposition
Authors: Zhao Zhao Hui , Zou Han Bo , Lin Wei Ming
Published: July 2012

A series of cobalt-molybdenum nitride catalysts were prepared using Co-Mo oxide precursors via temperature-programmed reaction in N2-H2 mixed gases. The catalysts were characterized by N2 physical adsorption, X-ray diffraction, temperature-programmed desorption of H2. Their catalytic performance was evaluated in the model reaction of ammonia decomposition. The influence of the final nitriding temperatures on the surface properties and the catalytic perfomance of CoMoNx/CNTs were described. The catalyst nitrided at 650°C shows the best catalytic performance. The results indicated that a suitable final nitriding temperature contributes directly to the formation of nitrides and favor the catalyst activity.
Chlorpyrifos-Loaded Attapulgite/Sodium Alginate Hybrid Microsphere and its Release Properties
Authors: Zhou Xin Hua , Liu Qi Hai , Ying Guo Qiang , Cui Ying De
Published: July 2012

With Ca2+ions as cross-link agent, chlorpyrifos-loaded attapulgite/sodium alginate hybrid microspheres were prepared by extrusion method. The hybrid microspheres were characterized by FITR, DSC, SEM techniques to gain insights into the structural and morphological features of the microspheres. Meanwhile, the release properties of the drug-loaded hydrogel microspheres for chlorpyrifos were tested. The experimental results indicate that, chlorpyrifos were loaded in calcium alginate microspheres in the forms of partial differential aggregation and molecular disperse, and there exists hydrogen bond between sodium alginate and attapulgite. The release effect of hybrid gel microspheres for chlorpyrifos can be divided into two stages, namely, the burst release and the sustained release. With the increasing of the attapulgite content, the release rate during the sustained-release phase and the amount of pesticide during burst release will be significantly reduced. The introduction of attapulgite can change the micro-phase structure of the drug-loaded sodium alginate gel, which is conducive to improve the release effect of gel microspheres for pesticides, thus promoting the release performance of drug-loaded sodium alginate microspheres.
Fractal Study on Collective Evolution of Short Crack for Low Cycle Fatigue at High Temperature
Authors: Tao Lu , Wang Zheng , Zheng Jian , Liu Chun Biao
Published: July 2012

Short cracks play the dominant role in material fatigue damage process, from the physical point of view, the solid containing cracks is actually a non-linear dissipation system, so it can be described by fractal theory. The evolution of short fatigue crack is a fractal curve, the irregular process can be described by fractal dimension. The material 20 steel in high temperature low fatigue is experimentally studied, the evolution of short cracks are observed. By analyzing experiment results, the fractal dimensions evolving with the evolution process are as follows, with the development of the damage degree, the fractal dimension is increased, and the dimension of the crack implicates many physical parameters, it can provide a reference for understanding the damage degree of material, it also provide reference for the life of short crack stage of material.
Experimental and Numerical Study of Premixed Combustion within Porous Media
Authors: Li De Bo , Xu Qi Sheng , Shen Yue Liang , Wen Zhi Yong , Liu Ya Ming
Published: July 2012

A transient numerical model and experimental study of combustion and heat transfer for methane and oxygen within a two-section porous burner are presented in this paper. It is found that the maximum flame velocity is influenced by the combined effects of extinction coefficient and convection heat transfer coefficient, and that the minimum flame velocities of ceramics with various pore densities have slight differences at different equivalence ratios, while maximum flame velocities have large differences. In addition, the flame velocity depends not only on the interfacial convection heat transfer, but also on the radiation heat transfer of the ceramic foams, which is in accordance with our numerical simulation. Meanwhile, the numerical research in the present paper indicates that radiation extinction coefficient or pores per inch is not the only reason to characterize the heat regeneration effect of ceramic foams.
Effect of Carbon Pretreatment on Cerium Loaded Activated Carbon as Desulfurization Adsorbents
Authors: Xiong Lin , Yan Xue Min , Mi Yuan Zhu
Published: July 2012

Activated carbon (AC) was pretreated by H2O2 or HNO3 and then loaded with cerium to obtain Ce/AC composites as desulfurization adsorbents. The adsorption isotherms of as-prepared Ce/AC composites for dibenzothiophene were measured in static batch desulfurization of model fuel and compared with the one prepared without AC pretreatment. It was found that both H2O2 and HNO3 pretreatment could enhance the adsorption capacity of Ce/AC composites. The results were discussed in terms of surface chemistry and texture property. The improvement could be related to increased surface acidic groups and better dispersion of loaded metal species bought about by the two pretreatment methods
Preparation and Characterization of SrO-Na2O-Fe2O3-FeO-P2O5-SiO2 Ferrimagnetic Glass-Ceramics for Hyperthermia Application
Authors: Liu Jian An , Yang Xue Na , Zhang Mei Mei , He Wen
Published: July 2012

The ferrimagnetic glass-ceramic based on SrO-Na2O-Fe2O3-FeO-P2O5-SiO2 system was prepared for hyperthermia application using aqueous aolution-melt method. Using the aqueous solution solvent evaporation, we obtained the molecular-scale homogenously glass precursor. The precursor was completely melted in a lidded platinum crucible placed in an electric furnace at 1480°C for 1h and then annealed in a furnace at 550°C for 40min.The annealed glasses were heat treated at 1050°C for 1h to obtain the glass-ceramics. The crystallization of the glass systems with different component has been systematically investigated by using XRD, TEM, as well as vibrating sample magnetometer (VSM). The glass-ceramics with P2O5=5.0wt% show a strong magnetic, which contains highest value of specific saturation magnetization of 24.89A•m2/kg.
Microstructures and Damping Capacity of Mg-6Zn-0.5Zr Alloy
Authors: Liu Xian Lan , Liu Chu Ming , Zhang Wen Yu , Luo Jian Hua , Zeng Su Min
Published: July 2012

The dynamic mechanical analyzer (DMA) was applied to investigate the damping properties of Mg-6Zn-0.6Zr alloys. The results show that the as-cast Mg-6Zn-0.6Zr alloy exhibits higher strain amplitude independent damping performance than that of as-homogenized. The strain amplitude dependent damping of the as-homogenized has the best damping performance with the strain amplitude from 3×10-5 to 6×10-4, and the as-extruded is the lowest. When the strain amplitude exceeded 6×10-4, the as-extruded has the best damping capacity all the time within the experimental strain amplitude, and all the alloys reach the high damping capacity. Two critical strain amplitude points were detected in the alloy as-extruded and as-homogenized. The damping peak value is 0.0192 with the strain amplitude of 1.5×10-3 presented in the alloy as-extruded.
Quantification of the N2+ Implanted AES Depth Profiles in Cobalt Films
Authors: Liu Yi , Wang Jiang Yong , Hofmann Siegfried , Kovac Janez
Published: July 2012

The nitrogen implanted profiles in cobalt films that are generated by N2+bombardment with three energies of 0.5, 2.0 and 5.0 keV are simulated by the analytical Schulz-Wittmaack expression and the SRIM program, respectively. Taking the both simulated profiles as concentration-depth profiles, the corresponding measured AES depth profiling data of implanted nitrogen are perfectly fitted by the Mixing-Roughness-Information depth (MRI) model.
Preparation of Reflective Silver Layers on Polyimide Substrate via Room Temperature Chemical Reduction Technique Using Hydrazine Hydrate as Reductant
Authors: Lin Hong Ji , Meng Xian Lin , Zhang Hai Yong
Published: July 2012

Reflective polyimide films were prepared by incorporation of silver ions in to the pre-hydrolytic layer of polyimide films, and subsequent treatment in hydrazine hydrate solution led to the reduction of silver ions to silver nanoparticles, which aggregated and formed continuous silver layers on both sides of polyimide substrate. The maximum reflectivity could be detected up to 80% on the downside and 90% on the upside surface, respectively. It was found that more silver loadings in the downside modified layers resulted in the two-sides difference in properties.
Effects of Affinity of Solvents on the Haze of Anti-Glare Films
Authors: Liu Bo Tau , Teng Ya Tsun
Published: July 2012

In the study we evaluated the effects of the solvents of the coatings and the process temperature on the haze of anti-glare (AG) films. We used the single solvent with different polarity or the mixture of two solvents to prepare the AG coatings on the same composition ratio of polystyrene microbeads to pentaerythritol triacrylate. Experimental results revealed that the haze value increased with the decrease of polarity of solvents, and the haze values of the AG films prepared at elevated temperature led to higher haze values. We speculate the results arose from the affinity of solvents to LSPs.
Study on Behavior of Ceramic Phases in Laser Surface Ceramic Process
Authors: Li Wei , Fang Qiang Han
Published: July 2012

Laser ceramic modification technology is an effective way to improve the surface performance of titanium alloy, mainly including laser cladding and laser alloying. This paper summarized the dissolution and precipitation behavior of ceramic phases during the laser ceramic process on the surface of titanium alloy.
Morphology and Distribution of M7C3 and TiC In Situ Synthesized in Plasma Surfacing
Authors: Su Yun Hai , Wu De Guang , Liu Guang Chao
Published: July 2012

In order to systematically study the morphology and distribution of M7C3 and TiC which in situ synthesized by plasma arc in the surfacing layer, plasma arc was used to clad the Fe-Cr-Ti-C wear-resistant alloy on low-carbon steel. And high corrosion experiment was applied to the surfacing layer. The hardness, microstructure and phase constitution of the surfacing layer were investigated through the tests of hardness, OM, EDS, SEM and XRD analysis. The results shows that irregular hexagonal (Cross-section) and strip (Side) M7C3 and petal-like, granular TiC were in situ synthesized in the surfacing layer. The M7C3 and TiC was combined closely. The M7C3 grains which closed to the fusion line of the base metal and surfacing layer are fine, but the ones that away from the fusion line are larger caused by the large temperature gradient. Smooth metallurgical bonding layer was formed between the surfacing layer and the base metal, it has a good metallurgical bonding. The phenomenon that carbon diffusion into the base material was clearly, the hardness near the fusion zone was improved effectively.
Superhydrophobic Sol-Gel Films Based on Copper Wafer and its Anti-Corrosive Properties
Authors: Fan You Hua , Li Chang Zhu , Chen Ze Jun , Chen Hong
Published: July 2012

Superhydrophobic copper wafer was prepared using a sol-gel deposition method in the paper. The best superhydrophobic film was prepared with vinyltrimethoxysilane (VTES), ethanol (EtOH), water (H2O) and ammonium hydroxide (NH4OH) at a molar ratio of 1:62.79:8.58:1.49 respectively. The morphologies, chemical compositions and hydrophobicity of the substrates were analyzed by scanning electron microscopy (SEM), energy dispersive X-ray detector (EDX) and water contact angle measurement (CA). The surface morphological study showed that “lotus like structure” silica particles distributed on the copper substrate. The coatings showed the CA as high as 157.8°. The durability properties revealed that the coatings had a good superhydrophobicity deposited in 3.5 wt % sodium chloride solution for up to 14 days.
Mechanisms and Application on Reduction Leaching of Pyrolusite by Cellulosic Biomass
Authors: Xue Jian Rong , Zhong Hong , Li Jin Zhong
Published: July 2012

Reduction leaching of pyrolusite by cellulosic biomass,due to its good performace,low cost,renewable and environmental friendliness，has received increasing attention in recent years.In this work，the advances on reduction leaching of pyrolusite by cellulosic biomass are reviewed.The degradation mechanisms of cellulosic biomass and reduction leaching applicat- ions of pyrolusite by degradation products are analyzed．Finally，further study of the proposed reduction leaching of pyrolusite by cellulosic biomass are discussed．
Electrochemically Deposited Thermoelectric Bismuth-Telluride Films
Authors: Liu Yan Ling , Yan Xiao Xia , Zeng Zhi Gang , Hu Zhi Yu
Published: July 2012

Thermoelectric bismuth-telluride films were successfully prepared from nitric acid aqueous solution with ethylene glycol on Ti-sputtered silicon substrates by electrochemical deposition techniques. Cyclic voltammograms (CV), X-ray diffraction (XRD), scanning electron microscope (SEM) and energy dispersive spectroscopy (EDS) were used to investigate nucleation process, the crystal structures, morphologies and compositions of the bismuth-telluride films. The results show that the materials are Bi-rich, exhibiting preferred (110) orientation with rhombohedral structure. The crystallite size of films was calculated based on Scherrer’s equation and found to be 18-20 nm.
Film-Forming Mechanism Analysis of Cerium Conversion Coating on Zinc Coating
Authors: Zhang Jiang Hong , Zhang Ying Jie
Published: July 2012

The zinc coating was immersed into a rare-earth conversion coating treatment liquid, with Ce(NO3)3•6H2O as the main salt and 30% H2O2 as the oxidizing agent. A Ce-H2O series potential-pH diagram and a Zn-H2O series potential-pH diagram were then established by calculating the maximum pH value obtainable on the interface. Therefore, the cerium conversion coating was deduced to be composed of ZnO, CeO2, Ce2O3, Ce(OH)3, and Ce(OH)4, In addition, XPS and XRD was used to analyze the appearance and phase of the cerium-based conversion coating in terms of the rare-earth conversion coating obtained in the experiment. The results reveal that the cerium-based conversion coating is the compound coating mainly consists of ZnO, CeO2, Ce2O3, Ce(OH)3 and Ce(OH)4, which is in line with the theoretical analysis.
Research on the Properties of Nanoparticles Modified Sodium Silicate Adhesive
Authors: Zhang Xin Li , Wu Yi Qiang , Hu Yun Chu
Published: July 2012

A kind of nanoparticles modified Na2SiO3 adhesive was prepared from Na2SiO3 aqueous solution with nano-silica and nano-magnesia as curing agent, and nano attapulgite as skeleton material. The chemical structure, surface morphology and thermal properties of nanoparticles modified Na2SiO3 adhesive were characterized by Fourier transform infrared spectrometer, scanning electron microscope, and thermo-gravimetric analyzer. As the two main measures of adhesion properties, the bonding strength and water resistance were also determined. The results showed that nanoparticles uniformly dispersed in Na2SiO3 matrix in the state of grain, so the homogenous morphology of cured adhesive was formed and bonding strength of Na2SiO3 adhesive was improved. Nanoparticles modified Na2SiO3 adhesive have good thermal stability in the range of 30~800 °C. The bonding strength and 24h water absorption rate of poplar plywood glued by the nanoparticles modified Na2SiO3 adhesive is 0.8 MPa and 23.7%, respectively, reaching the type-two plywood performance standards.
Non-Volatile Memory Behaviour of MFIS Structure with Ba0.7Sr0.3TiO3 Films for Memory Capacitor Application
Authors: Nwe Htet Htet , Maung Yin Maung , Win Than Than , Soe Ko Ko Kyaw
Published: July 2012

The growth of strontium doped barium titanate (BST) powder is performed by solid-state reaction. Microstructural characterization by SEM technique confirms the BST film is successfully formed on p-Si (100) substrate by spin coating technique. Dielectric properties of MFIS (Metal/ Ferroelectric/ Insulator/ Semiconductor) designs are measured by impedance analyzer (LCR meter, QuadTech :1730). P-E (polarization-electric field) hysteresis loops are also measured by applying the same triangular wave electric field in order to allow their application in NVFeRAM (Non-Volatile Ferroelectric Random Access Memory). The maximum remanent polarization density (Pr=38.6µC/cm2) is found at BST film 600°C. The film exhibits the potential to be a future promising memory. The results obtained from this research are quite interesting, acceptable, credible and applicable in use for NVFeRAM.
Fabrication of Hydrophobic Magnesium Alloy Surface by Wet-Chemical Methods
Authors: Liu Yan , Li Liang , Li Rui Feng , Han Zhi Wu , Yu Si Rong
Published: July 2012

Commercially available magnesium alloy is extensively used in structural engineering components although, like many magnesium-based materials, it suffers from poor corrosion resistance, particularly in moist environments, which limit wider application. Previously, by reducing the contact area of metal substrate with surrounding water environment and decreasing the risk of corrosion is shown to improve the corrosion resistance of magnesium alloy in humid environments and in the presence of chloride-containing aqueous environments. The objective of this study, without the low-surface-energy materials modification, is to fabricate the superhydrophobic surfaces by wet-chemical methods and to understand how the microstructure influences the surface wettability of unstable materials such as magnesium alloy. The influence of the variety of experiment conditions on the wettability of the substrates was investigated by a contact angle goniometry with water as a probe liquid. Scanning electron microscopy and energy dispersive spectroscopy were used to study the surface chemistry and microstructure at various stages of the multi-wet-chemical process.
Hydrothermal Synthesis of Lead Titanate Powder and Epitaxial Thin Film for Memory Capacitor Application
Authors: Thu Chaw Loon , Win Than Than , Maung Yin Maung , Soe Ko Ko Kyaw
Published: July 2012

This lead titanate (PbTiO3) powder was prepared by classical hydrothermal synthesis with different TiO2 contents at low temperature. Phase identification and crystal structure of product PbTiO3 powders were examined by X-ray diffraction (XRD). From XRD result, hydrothermal synthesized PbTiO3 powder was significantly formed with tetragonal symmetry. Structure morphologies of PbTiO3 films were observed by scanning electron microscopy (SEM). Ferroelectric properties and nonvolatile memory behaviour of PbTiO3 films were identified by means of C-V characteristics. The widths of memory window were measured to be 0.50 V and 0.56 V for PbTiO3 film with 0.20 g and 0.22 g of TiO2 content.
Studies on Surface Morphology of Water-Based Silicone Rubber/Silica Sol Hybrid Coatings by Atomic Force Microscopy
Authors: Wu Li , Deng Wei Xing , Peng Jin Wen , Lin Xiao Dan , Ma Wen Shi
Published: July 2012

Hybrid coatings had been prepared with water-based silicone rubber, silica sol and curing agents. This material has strong adhesion and coating properties to wood, glass, metal, ceramic, brick etc. The hybrid coatings were analyzed by atomic force microscopy (AFM). The results show that different curing agents play a key role in surface morphology of hybrid coating. Methyltris-(methylethylketoxime)silane（MOS）cured hybrid coating looks smooth and flat. When the concentration of curing agent was 3.0 wt%, the surface roughness of 20 wt% silica sol hybrid coating was only 47.2 nm. At the same conditions, 3-triethoxysilylpropylamine (APTES) cured hybrid coating displays cluster structure and the surface roughness of hybrid coating could reach 368 nm in height. With the increase of the concentration of APTES, the cluster structure becomes more obvious and the surface roughness also increases gradually. When the concentration of silica sol is increased from 15 to 30 wt%, with 3.0 wt% APTES as curing agent, the surface roughness of the hybrid coating increases from 312 to 511 nm, respectively.
Preparation and Characterization of Nano-SiCP Strengthened MCrAlY Graded Coating by Laser Multi-Layer Cladding
Authors: Wang Dong Sheng , Tian Zong Jun , Yang Bin , Shen Li Da
Published: July 2012

Nano-SiC/MCrAlY graded coating was prepared by laser multi-layer cladding on TiAl base intermetallic alloy using composite MCrAlY powders with 1%, 2%, and 3% nano-SiC particles (mass fraction) in turn. The microstructure and microhardness of the composite coating were analyzed by means of scanning electron microscope (SEM) and Vickers microhardness tester. The results show that the microstructure of the composite coating was refined and composed of fine equiaxed grains because of addition of nanometer SiC particles, and the crystal size becomes small with increasing the nano-SiC content in the coating. In addition, due to small size and formation heat of the nano-SiC particles, SiC particles decompose and form new carbides in the coating after laser cladding. The hardness of the composite MCrAlY coating is obviously improved due to enhancement of multi-carbide and refinement of structure.
Effects of pH Value on Performance of CdS Films with Chemical Bath Deposition
Authors: Zhou Li Mei , Hu Xiao Fei , Wu Su Mei
Published: July 2012

CdS thin films were prepared by chemical-bath deposition (CBD) from a bath containing thiourea, acetic cadmium, ammonia and ammonium acetate in aqueous solution onto glass substrates at 80°C with stirring. The influence of pH value on the surface morphology and optical properties of the CdS thin films was investigated. Step height measurement instrument, scanning electron microscopy (SEM), X-ray diffraction (XRD), spectrophotometer and digital four-point probe resistance measurement were used to characterize their thickness, surface morphology, crystal structure, electrical and optical properties. Uniform CdS thin films were obtained when pH=11.6. There are obvious diffraction peaks at 26.04° when pH is 11.6. The transmittance increases as the pH values increase. The experiment show that pH value play a vital role in the properties of the CdS thin films.
Preparation and Magnetic Properties of Electroless Ni-Fe3O4 Composite Plating on Polyester Fabric
Authors: Li Ya Ni , Guo Rong Hui , Lan Jian Wu , Jiang Shou Xiang , Lin Shao Jian , Chen Si , Shang Jiao Jiao
Published: July 2012

In this study, Ni-Fe3O4 composite particles are deposited on polyester fabric modified with 3-aminopropyltrimethoxysilane (APTMS) by electroless plating. Surface morphology, chemical composition and crystal structure of the Ni-Fe3O4 deposits were investigated by scanning electron microscopy (SEM), energy dispersive X-ray (EDX) and X-ray diffraction (XRD), respectively. The magnetic properties of the Ni-Fe3O4 composite plated polyester fabric are also evaluated. Relatively dense plating was obtained under the given plating conditions. As the Ni-Fe3O4 weight on the treated fabric is 34.28g/m2, the saturation magnetization of the sample was 2.88emu/g.
P-Doped p-Type ZnΟ Films Deposited by Sputtering and Diffusing
Authors: Zhu Hui Qun , Li Yu Ming , Li Jun Long , Sun Ling
Published: July 2012

P-doped ZnO thin films were prepared on different Si substrates by RF magnetron sputtering in Ar and O2mixed atmosphere. The P-doped ZnO films were changed from n-type to p-type by phosphorus diffusing from the n-Si substrates with higher phosphorus concentration into the ZnO films during depositing. The crystal structure of the ZnO films was examined by X-ray diffraction and confirmed to belong to wurtzite and highly c-axis oriented primarily perpendicular to the substrate. The Hall effect measurement results show that the corresponding hole concentration and risistivity of the P-doped ZnO film was 8.982×1017cm-3and 1.489 Ω•cm respectively. This reveals that the P-doped ZnO thin film is really p-type behavior.
Effect of Nitrogen Flow Rate on the Structure and Properties of TiN Thin Films Deposited onto β-Type Ti-15Mo-3Nb-3Al-0.2Si Alloy Substrates by Reactive Magnetron Sputtering
Authors: Lee Jun Hee , Nathanael A. Joseph , Hong Sun Ig
Published: July 2012

Titanium Nitride (TiN) thin film was deposited on β-type Ti-15Mo-3Nb-3Al-0.2Si alloy plates by RF magnetron sputtering method. The effect of nitrogen flow rate on the structure and properties of the TiN thin films were studied. The preferred orientation of TiN thin films changed from (111) to (200) as the nitrogen flow rate increased due to the effect of the kinetic energy of the bombarding particles. The coating thickness was found to decrease with increasing nitrogen concentration, which also favors (200) orientation with increasing nitrogen flow rate. With increase of nitrogen flow, the morphology of the TiN thin films films changed from characteristic pyramidal shaped grains to columnar-shaped grains. The roughness analysis of the coating shows that the average roughness of the coating decreased with increasing nitrogen flow rate. The increase of hardness with increasing nitrogen flow rate is attributed to the decrease in grain size.
Multimedia Technology Application in Teaching Basketball Skills
Authors: Lv Hong Ning
Published: July 2012

Technology and multimedia tools are constantly evolving and providing instructional designers new ways to present instruction. While the evolution of technology is full of instructional design potential, more research is needed to understand the cognitive processes when learning with different combinations of multimedia. The paper intends to interpret the application of multimedia technology in teaching basketball skills.
Research of Thread Mechanism in Communication Network
Authors: Ma Yong Guang , Zheng Bing , Ran Ning
Published: July 2012

In the network communication, communication systems require multiple tasks simultaneously and independently, and each task needs constantly performing before termination in normal. In order to meet the demand, put forward the multi-channel thread method in communication process. Based on TCP / IP protocol socket network communication, in order to make the server effectively distinguish between multiple client task and accurate transmission of information, using multi thread method processing communication details, ensure the separate and concurrent of communication between each node and server. Deep understanding and flexible use of thread method to the communication process is the key to network communication.
An Algorithm of Iterative Learning Control Based on Vector Plots Analysis and its Robustness
Authors: Liu Chang Liang , Jia Wan Gen
Published: July 2012

Abstract: In order to solve the problem of slow convergence, an iterative learning control algorithm based on vector plots analysis is proposed. By introducing the geometric principle, that angle and side length of corresponding relationship in the same triangle, and transforming output’s error relationship into the relationship of the angel, the P-type is rewarded or penalized. The new algorithm with angle-correction speeds up significantly the convergence process. For illustration, a numerical simulation is utilized to show its efficiency and superiority. Empirical results show that the new algorithm is faster than P-type to make the system convergence .The method modifying P-type by angle is entirely feasible. The system’s output converges to the desired trajectory. The new algorithm can effectively solve the slow convergence problem. Introduction
A Two-Grid Discretization Scheme for a Sort of Steklov Eigenvalue Problem
Authors: Xia Chao , Yang Yi Du , Bi Hai
Published: July 2012

On the basis of Yang and Bi’s work (SIAM J Numer Anal 49, p.1602-1624), this paper discusses a discretization scheme for a sort of Steklov eigenvalue problem and proves the high effiency of the scheme. With the scheme, the solution of an eigenvalue problem on a fine grid is reduced to the solution of an eigenvalue problem on a much coarser grid and the solution of a linear algebraic system on the fine grid. And the resulting solution can maintain an asymptotically optimal accuracy. Finally, the numerical results are provided to support the theoretical analysis..
Digital Design Research on Color Simulation of Woven Trademark
Authors: Jin Zi Min , Ou Ya , Yan Juan , Si Hong
Published: July 2012

According to the principle of trademark weave and color collocation, weft backed gradual weave-database has been designed, which is applicable to trademark production. A series of color items have been constructed which consisted of red, yellow, blue, green and black five basic color’s combination and collocation in the light of three kinds of color development. And combined with the color expression of weft backed gradual weave-database, the chromatography of color simulated trademark has been set up.
Mathematical Simulation Analysis of Concrete Perforated Bricks with Three-Dimension Conjugate Heat Transfer
Authors: Xie Hong Bo , Ma Wei Bin
Published: July 2012

3-D heat transfer behaviors in two types of concrete perforated bricks used in external walls were numerically simulated. Air density was modeled both with Boussinesq assumption and ideal gas model, and air thermal properties were calculated alternatively with constant and polynomial parameters. Results of four different inputs shown us that there had little difference between them and they agreed well with Guard hot box tests. The effective conductivity of bricks decreased with increase of the air interlayer thickness at first and then increased as it continued to increase, which meant that thickness of the air interlayer was crucial to insulation effect of bricks. This was because of the cooperation of the conduction and natural convection. Under the same condition, effective conductivity is proportional to concrete conductivity.
Based on the Improvement of Grey Target Theory in Diesel Engine Fault Diagnosis
Authors: Zhang Cui Xia , Liu Cong Hu
Published: July 2012

Based on the practical operation of diesel engine fault and a lot of professional experience and knowledge, an improved gray target engine fault diagnosis model was proposed. The ault sign standard model structure was built by Fault-to-date statistical data and professional experience and knowledge,and multi-target heart Failure was constructed. The causes of a diesel engine was diagnosed through the fault symptoms and the cause of the malfunction bull's-eye from all sort and its practicability and validity have been indicated by its result.
Numerical Study of Shellside Performance of Heat Transfer and Flow Resistance for Heat Exchanger with Trefoil-Hole Baffles
Authors: You Yong Hua , Fan Ai Wu , Chen Chen , Fang Shun Li , Jin Shi Ping , Huang Su Yi
Published: July 2012

Trefoil-hole baffles have good thermo-hydraulic performances as the support of heat pipes, however the published research paper is relatively limited. The present paper investigates the shellside thermo-hydraulic characteristics of shell-and-tube heat exchanger with trefoil-hole baffles (THB-STHX) under turbulent flow region, and the variations of shellside Nusselt number, pressure loss and overall thermo-hydraulic performance (PEC) with Reynolds number are obtained for baffles of varied pitch with the numerical method. CFD results demonstrate that the trefoil-hole baffle could enhance the heat transfer rate of shell side effectively, and the maximal average Nusselt number is augmented by ～2.3 times that of no baffle, while average pressure loss increases by ～9.6 times. The PEC value of shell side lies in the range of 16.3 and 73.8 kPa-1, and drops with the increment of Reynolds number and the decrement of baffle pitch, which indicates that the heat exchanger with trefoil-hole baffles of larger pitch could generate better overall performance at low Reynolds number. Moreover, the contours of velocity, turbulent intensity and temperature are presented for discussions. It is found that shellside high-speed jet, intensive recirculation flow and high turbulence level could enhance the heat transfer rate effectively. Besides good performance, THB-STHXs are easily manufactured, thus promise widely applied in various industries.
Numerical and Experimental Fractal Pore Network Study on Drying of Porous Media: Model Building
Authors: Yuan Yue Jin , Yuan Yue Ding , Xu Ying Ying , Dong Ji Xian , Liu Xiang Dong
Published: July 2012

In view of the fact that the two-dimensional square pore network model screened many microstructure features and transfer characteristics inside porous media, a fractal pore network model for unsteady drying process of natural porous body was developed on the base of fractal geometry theory and transport process principle, which took various factors into consideration, such as the liquid-phase flow, vapor-phase diffusion, temperature gradient, and pore microstructure characteristic.