bluuebunny/crossref_metadata_2025 huggingface dataset:
Hydroxyapatite Whisker Effect on Strength of Calcium Phosphate Bone Cement
Authors: Zhao Ping , Zhao Shuai , Zhao Tai Rong , Ren Xue Hua , Wang Feng , Chen Xiu Na
Published: June 2012

Hydroxyapatite whisker was the reinforcement phase to prepare whisker/calcium phosphate cement composites, which was obtained by homogeneous precipitation method, with 2.5~15 microns in length, 2~30 length/diameter ratio. Mechanical properties and microstructure of composites were tested. With the increase of hydroxyapatite whisker addition, composites strength reduces after the first rise. When hydroxyapatite whisker is added to 4%(wt), the composite achieves the maximum strength. SEM method was used to observe fracture microstructures of composite materials. As a result, dispersion degree of the HA whisker affects the strength of the material. Too much whiskers can form agglomerates, which weaken composite strength.
Fitting and Prediction of City’s API Based on RBF and Application of CCRBF Model in Atmosphere Environmental Quality
Authors: Gong Min Qing , Sun Ming Wei , Jin Ming Zhong
Published: June 2012

In this essay, the atmosphere environmental quality assessment of Guiyang was set as an example. A RBF model of the time series of API was built to fit and evaluate urban API on the basis of the concentration of 、 and inhalable particulate matter(PM10) in atmosphere. A CCRBF model used to test and predict atmosphere environmental quality was proposed by coupling canonical correlation analysis and RBF neural network based on various factors influencing urban atmosphere environmental quality. The analysis showed that the CCRBF simplified the quantity of factors effectively and was of higher fitting and prediction accuracies than regression model.
UV Induced Degradation of Crude Oil in Polluted Water Based on Analysis of Environmental Materials
Authors: Liu Hui , Sun Bing , Yan Zhi Yu , Tian Xiao Yu
Published: June 2012

Analysis of environmental materials is very important for the environmental assessment, especially for the crude oil-contaminated water. This paper investigated the degradation of crude oil in the polluted water under the irradiation of UV light, and used the UV absorption, synchronous fluorescence spectra and gas chromatograph to analysis the changes of the environmental materials in the crude oil polluted water during the irradiation. All of the absorbance substances, fluorescent substances and saturated hydrocarbons in the crude oil polluted water decreased with the UV light irradiation. In addition, the dissolved organic matters in the seawater had significant influence on the photodegradation of crude oil.
Study of Analysis Technology of Organic Carbon in Sediment as Powder Materials with Ozonation Chemiluminescence Method
Authors: Liu Yan , Zhang Hong Bin , Ma Ran , Ren Guo Xing
Published: June 2012

A method for rapid analysis on-site of organic carbon in sediment powder materials is recommended. It is based on researches on the phenomenon of chemiluminescence of organic carbon in sediment powder materials reacting with ozone. A Chemiluminescence kinetics curve was obtained by using an home-made experimental instrument, and used to analyze content and characteristics of the organic carbon in sediment powder materials, such as the proportion of hard oxidation , easy oxidation and middling stabilization. Effectiveness of the method was verified comparing its results with those of the existing detection method. Based on the finding that sediments powder materials varied sharply in chemiluminescence feature from type to type, a concept of “organic carbon fingerprint” is recommended.
600MPa Grade TMCP Steel with Low Yield Ratio and Excellent Weldability
Authors: Tong Ming Wei , Yuan Ze Xi , Zhang Kai Guang
Published: June 2012

A new lower cost 600MPa TMCP steel with high strength,good low temperature impact toughness,low yield ratio and excellent weldability has been developed successfully by design of alloy composition and thermal mechanical control process technology, and the welding heat affected zone(HAZ) have been investigated. The systematic studies show that the new developed steels gather high strength, high low temperature toughness, good seismic performance(low yield ratio) and excellent weldability, and the base steels have a good match of strength and toughness. A large number of fine acicular ferrite in HAZ can ensure that the welding plate has high strength and good low temperature impact toughness. The comprehensive performance of steel can meet fully the high-technical requirements of large-scale engineering.
Study on Rheology of UHMWPAN /MMWPAN/DMSO Solution
Authors: Xu Dong , Han Qiu , Chen Hui Fang
Published: June 2012

Adding a mount of MMWPAN to UHMWPAN/DMSO dilute solution is a good way to increase the total PAN content (including MMWPAN and UHMWPAN) while the UHMWPAN content of the solution is hard to be increased. In this paper, the rheological properties of UHMWPAN/MMWPAN/DMSO solution and the role of UHMWPAN in this solution were studied. The complex viscosity (h*) and the steady shear viscosity (h) both increased as the UHMWPAN content rising.
The Optimization of Synthesis Condition of ZnSe Nanocrystals
Authors: Wang Ting , Guo Li
Published: June 2012

In biomineralization, self-organization of organic based templates provides scaffolding for the assembly of QDs materials. The host-guest relationship between these protein cages and the encapsulated material is based primarily on a complementary electrostatic interaction. Zinc selenide (ZnSe) were synthesized in the cavity of the apoferritin from horse spleen (HsAFr) and the reaction condition was optimized by adding tween 20 to avoid ferritin agglomeration. The obtained nanodots were characterized by TEM, and absorption measurements. In addition, the protein concentration of ZnSe-ferritin was precisely measured by the Bradford protein assay method. From the results, it was concluded that the ZnSe nanocrystals were successfully synthesized in the core of ferritin and it can be applied as a potential functional material such as transistors, biosensor materials or medical imaging.
Application of Power Ultrasound in Coal Seam Water Infusion
Authors: Meng Jun Qing
Published: June 2012

The infusion increase mechanism of power ultrasound on coal seam water infusion and its prospect of application are introduced. The research results show that: the main mechanism of power ultrasound to coal and water are mechanics and cavitations function. The porosity and permeability of coal can be improved due to the power ultrasound, so the speed of the water into the coal is improved. The technology of power ultrasound on the coal seam water infusion has a good application prospect.
Optimization Study on Frame Material of Mini Wind Generator Base on FEM Stress Analysis
Authors: Wang Shu Fang
Published: June 2012

A new kind of mini wind generator system has been presented for saving city electricity and developing potential green wind energy between high buildings in city environment. The support frame of this generator system is a key structure part. Stress conditions of this frame under different kinds of structure materials are analyzed with finite element method. The concentration of stress along frame pillar is achieved by the FEM results. A new analytical method, specified stress criterion is proposed with respect to the design of generator system. This criterion provides a new approach in optimizing the kind of material in structure design taking into account the material plastic properties. With regard to specified stress, glass fiber-reinforced epoxy is the best candidate material for supporting frame.
Research of Novel Functional Stealthy Nanomaterials
Authors: Wang Qiang , Sun Ling Na , Hu Chang Wen , Cao Chuan Bao
Published: June 2012

With the continuous development of Electronic Warfare Technology (ECM) and new requirements of military modernization, stealthy technology played an important role in military equipment. Mechanism of new stealthy continues to be broken through and numbers of successful developments of new types of stealthy materials are put into use. New stealthy materials are the basis and key of stealthy technology and their developments are promoted by the improvements of detection and guidance of military technology. The studies of new stealthy functional nano-materials are analyzed and the stealthy mechanism of functional materials is introduced. The research progress, classification, preparation methods and the radar absorption mechanism of stealthy for new stealthy functional nano-materials are discussed. The new stealthy functional nano-materials are compared with the traditional radar absorption materials. The development trend and application prospects of stealthy functional nano-materials are also estimated.
One-Step Synthesis and Antibacterial Properties of Polyaniline/TiO2 Nanocomposites
Authors: Hu Ting Wei , Shan Shao Yun , Yang Shi Mei , Jiang Li Hong , Wang Ya Ming , Jia Qing Ming
Published: June 2012

Polyaniline(PANI)/TiO2 nanocomposites are successful synthesized by one step-interfacial polymerization method. Morphologies and structures of the nanocomposites are characterized using SEM, FTIR, and XRD. The antibacterial properties of PANI/TiO2 nanocomposites on Staphylococcus aureus, Bacillus subtilis, Escherichia coli, Bacillus megateriu and Bacillus cereus are tested. The effect of molar ratio of aniline and tetrabutyl titanate on structures and antibacterial properties are also been explored. The results show that the content of tetrabutyl titanate has a obvious influence on structure and morphologies of the nanocomposites. PANI/TiO2 nanocomposites have antibacterial properties especially on Staphylococcus aureus and Escherichia coli, which shows a best antibacterial property when the molar ratio of aniline to tetrabutyl titanate is 3:2.
Preparation of Fibrous CaO Sorbent by Hydrothermal Method
Authors: Yang Shi Mei , Shan Shao Yun , Jia Qing Ming , Hu Ting Wei , Jiang Li Hong , Wang Ya Ming
Published: June 2012

Using urea and calcium chloride as precipitator and calcium source, fibrous CaCO3 precursors were prepared using hydrothermal method, then fibrous CaO sorbent was obtained by calcination. The influence of hydrothermal temperature on CO2 absorption properties was discussed. X-ray diffraction analysis showed that pure CaCO3 phase with aragonite and calcite crystal forms was obtained. Scanning electron microscopy analysis showed that the resultant CaO sorbent presented a fibrous microstructure, which inherited the morphologies of CaCO3. The absorption capacity of the resultant CaO sorbent reached 59.86%, being 76% of theoretical absorption capacity. In addition, compared with the CaO sorbent from analytical pure CaCO3, the obtained fibrous CaO-sorbent have the better cyclic absorption properties.
Microstructure and Mechanical Properties of Ti1-xAlxN Thin Films
Authors: Zhong C.L. , Wei P.A. , Luo L.E.
Published: June 2012

A series of Ti1-xAlxN thin films were deposited by reactive magnetron sputtering. The content, microstructure and the hardness of the thin films were characterized respectively with energy dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD) and nanoindentor. The effect of Al content on the microstructure and hardness was studied. It was found that Ti1-xAlxN compound thin films exhibits a cubic structure with (1 1 1) preferred orientations and that the lattice parameter of Ti1-xAlxN thin films decrease with the increase of Al content. The hardness of Ti1-x AlxN compound thin films is higher than that of TiN and increases with the increase of Al content. At the heat-treated temperature T = 600 °C, the Ti1-xAlxN thin films is still of high microhardness.
Investigation on Dislocation Network in Al-5.8Cu Aluminum Alloy Impacted Plate
Authors: Zhang Yu , Guan Hong , Gao Zhi Guo
Published: June 2012

Split Hopkinson pressure bar setup was used as experimental method for dynamic impacted testing at 573K at the strain rate of 7030s-1. The microstructure of Al-5.8Cu aluminum alloy impacted plate was characterized by transmission electron microscopy (TEM). The findings indicated that dislocation network of Al matrix was observed, which was attributed to isothermal and adiabatic process during impaction. The researched results indicated the dislocation network of Al matrix was inhabited by coarsened precipitate in Al-5.8Cu alloy impacted plate.
Mechanical and Thermal Properties of Reactable Nano-SiO2/polyoxymethylene Composites
Authors: Xu Xiang Min , Guo Li Ping , Zhang Yu Dong , Zhang Zhi Jun
Published: June 2012

The polyoxymethylene-based composites containing reactable nano-SiO2 were prepared in a twin-screw extruder by melt compounding, and mechanical and thermal properties of pure polyoxymethylene (POM) and composites were investigated. The results showed that reactable nano-SiO2 could reinforce the tensile strength and Young’s modulus of composites. To the impact strength of composites, there was obvious improvement when a small amount of silica was added into POM. With the increase of silica content, the impact strength of composites showed a gradually decrease trend. It was worthy to note that reactable nano-SiO2 could significantly increase the decomposition temperature of POM. When the content of reactaSubscript textble nano-SiO2 was up to 5 wt%, the degradation temperature of composites could increase about 38.3°C under nSubscript textitrogen atmosphere and 43.8°C under air atmosphere, respectively, compared with pure POM. Furthermore, the differential scanning calorimetry (DSC) analysis showed that reactable nano-SiO2 had a good heterogeneous nucleation capability in POM, and could increase crystallization temperature of POM, but surface structure of reactable nano-SiO2 was not propitious to the growth of POM crystals, accordingly leading to the decreasing crystallinity of composites.
Precise Re-Os Dating of Molybdenite from the Northern Dabie Molybdenum Belt in Central China and its Geodynamic Implications
Authors: Li Jun Ping , Li Yong Feng , Xie Ke Jia
Published: June 2012

The Dabie orogen of east-central China marks the boundary between the North China and Yangtze Cratons, and is characterized by juxtaposition of the ~400Ma Tongbai metamorphic belt and the ~220Ma South Qinling-Dabie metamorphic belt. The Triassic collision between the North China and Yangtze Cratons which generated numerous granitoid intrusions such as the Shangcheng, Xingxian and Lingshan intrusions, and other small stocks, such as Tangjiaping, Dayinjian, Mushan and so on. Those shallow-emplaced granite porphyries are closely related to porphyry-skarn Mo and Mo-W deposites, forming the Dabie molybdenum metallogenic belt. Molybdenum deposits occur in the endo- and exocontact zones of the porphyry, include with three major types of Mo mineral systems, i.e., porphyry, less porphyry-skarn and vein-type. The ore-forming ages of the molybdenum deposits in Dabie area are mainly cluster 127.8±0.9~113.1±7.9Ma. The pulse is the product of the transformation of the tectonic regime from NS- to nearly EW-directions in East China.
Comparative Analysis of Bacterial Diversity for Cutlassfish (Trichiurus haumela) during Cold Storage by the Culture-Dependent and Culture-Independent Methods
Authors: Lan Wei Qing , Xie Jing
Published: June 2012

The methods of culture-dependent and denaturing gradient gel electrophoresis (DGGE) based on the sequence of 16S rRNA V3 region gene were described to comparatively characterize the microbial population and community structure of cutlassfish (Trichiurus haumela) under the cold storage. The results showed that 13 kinds of bacteria were identified by the traditional culture-dependent methods, the dominant bacteria belonged to Shewanella putrefaciens and Pseudomonas fluorescens. To determine the community profiles of the samples on variable V3 region, the bacteria of 16S rRNA gene were amplified by PCR and 11 distinct PCR products were separated by DGGE fingerprinting technology. From the sequence analysis, Psychrobacter sp. was found to be the predominant bacteria in the initial stage of the storage. The proportion of Shewanella sp., Pseudomonas sp. increased gradually with the extension of storage time, and they took the place of Psychrobacter sp. to be the dominant bacteria. Thereinto, both Pseudomonas fluorescens and Vibrio sp. took high proportions in the process of storage due to the deterioration of cutlassfish (Trichiurus haumela).
Effect of Modified Atmosphere with Varying O2 Concentrations on the Quality of Packed Pacific White Shrimp (Penaeus vannamei) during Cold Storage
Authors: Qian Yun Fang , Xie Jing , Yang Sheng Ping , Xiong Qing , Zhang Li Ping , Gao Zhi Li , Wu Wen Hui
Published: June 2012

The purpose of this study was to evaluate the effect of modified atmosphere packaging (MAP) with varying O2 concentrations on the quality changes of Pacific white shrimp during cold storage at (4±1)°C by using the quality indices such as Total viable counts (TVC), TVB-N, pH, firmness, whiteness and sensory evaluation. Results showed that MAP inhibited the microbial growth and the spoilage which was confirmed by the lowered TVC and TVB-N. Among the four MAP groups, shrimp packaged in bags 40%CO2\55%O2\5%N2 showed the lowest level of TVC and TVB-N, and shrimp in 40%CO2\5%O2\55%N2 had the best appearance with lighter blackspots during storage. Low O2 concentration packaging exhibited the ability to retard melanosis, but weakening the ability to impede the spoilage. Extremely high O2 concentration with low CO2 concentration packaging inhibit the microbial growth compared to the CK, but improved the melonasis of shrimp and reduced its sensory quality rapidly.
Synthesis of Graft Copolymer by Using Acrylamide and Methacryloyl Chloride Guar Gum and its Adsorption Behavior to Metal Ions
Authors: Dong Li Tao , Zhu Jie , Xiao Weng Fa
Published: June 2012

a graft copolymer has been synthesized by reaction of acrylamide (AM) with methacryloyl chloride guar gum (MAG). The reaction condition was optimized, and the graft copolymer was characterized by FTIR and Scanning electron microscopy (SEM). Moreover the absorption behavior of the graft copolymer to metal ions at different conditions was studied.
Synthesis and Characterization of Poly Phenoxyl Bisphenol-S Phosphate
Authors: Ban Da Ming , Min Yang , Zhang Yong Hang , Zhao Ou
Published: June 2012

A solid phase bisphenol-S bis(diphenyl phosphate)(BSDP), Poly Phenoxyl Bisphenol-S Phosphate（S-BSDP）was synthesized from phosphorus oxychloride, phenol and bisphenol-A in two step sythesis route. The influence factors on the yield and molecular weight of S-BSDP were investigated by the means of orthogonal design. The structure of S-BSDP was characterized with Fourier Transform Infrared Spectroscopy (FTIR). The molecular weight was determined by Gel Permeation Chromatography (GPC). Thermal stability of S-BSDP was studied by Thermal Gravimetric Analysis (TGA). The results review that S-BSDP was synthesized successfully and its structure is similar to BSDP. Its thermal decomposition temperature is much higher than liquid phase BSDP.
Fabrication and Characterization of Poly L-Lactic Acid/Modified Nano-Hydroxyapatite Composite Fibrous Scaffold
Authors: Cheng Zhi Qiang , Pang Gui Hua , Wang Hong Yan , Li Jun Feng , Zhao Xue Zhong
Published: June 2012

Nano-hydroxyapatite were modified with biocompatible polyethylene glycol (PEG) by surface coating, so modified nano-hydroxyapatite particles (modified nano-HA) were prepared. A homogeneous solution was obtained by dispersing the modified nano-HA into poly l-lactic acid (PLLA) solution. Composite fibrous scaffold was fabricated via electrostatic spinning method with the homogeneous solution. The composite fibrous scaffold was characterized by SEM, TEM and XRD techniques. The characterization results showed that the surface morphology of the composite fibrous scaffold was smooth, modified nano-HA was dispersed in PLLA homogeneously, the hydrophilicity of composite fibrous scaffold were increased obviously. Adipose-derived stem cells (ADSCs) proliferating in the fibrous scaffold were investigated by using laser scanning confocal microscope observation.
Analysis for Stress-Strain Curve during Stretching Coarse Yak Hair with Different Pretreating Condition
Authors: Liu Jian
Published: June 2012

The changes, on stress-strain curve of coarse yak hair piece with different pretreating condition, have been analyzed during stretching slenderization in this paper. The result shows that the reagent of pretreatment could break the S-S bond effectively to prepare for stretching, and the pretreatment reagent will damage the structure of yak hair fiber if the pretreating time is more than 10min. From curve analysis, it shows that the stretching speed raising will cause the strengthening point brought forward and the yak hair fiber will bear more action force when stretching, and slow stretching could reduce the damage effectively to the structure of yak hair fiber. In addition, part of fibers would have some slippage or breakage on yak hair pieces when stretching slenderization happen.
Study on Multi-Elements in Traditional Chinese Medicines Ophiopogon japonicus and Lotus Seeds by the ICP-AES with Microwave Digestion
Authors: Zhang Sheng Bang , Ji Xiao Wu , Liu Cui Ping
Published: June 2012

Abstract: Determination of multi-elements were studied in the food cooked with medicinal herbs Ophiopogon japonicus（OJ） and Lotus seeds by ICP-AES after HNO3-H2O2 digestion with microwave. The average recoveries are in 91.7%~ 102.4% of As, Cr, Se, Cd, Cu, Mn, Zn, Al, Ba, Fe, Ni, respectively. The relative standard deviation(RSD)is less than 2.8% except Al （9.4%）and detection limit is in the range of 0. 10µg/L ~8.5µg/L except Al （79.6µg/L）. The difference was very obvious（p0.001,except As） that the elements’ content on the comparison OJ with Lotus seeds. There was rich of the trace elements Cu, Zn. The harmful element Al was on the high value（214.7µg/g）in the OJ. It is of important significance to assess the value of the food cooked with medicinal herbs by determination of multiply elements in Lotus seeds, and OJ with ICP-AES. Keyword: multi-elements, the trace elements, the harmful elements, Ophiopogon japonicus, Lotus seeds, ICP-AES
Effect of Process Parameters on Jet Length in Electrospraying of Thermoplastic Polymer
Authors: Jadhav Amit , Wang Li Jing , Lawrence Carl , Padhye Rajiv
Published: June 2012

Electrospraying is inexpensive and an effective way to produce submicron range coating. Spray Angle and Jet Length are important characteristics that affect coating quality while polymer solution subjected to electrospraying. It was of interest to determine the effect of the process parameters on Jet Length. In this paper, an attempt was made to apply the electrospraying concept for coating textile surfaces. Series of experiments were carried out employing different settings of process parameters such as voltage, nozzle-collector distance and polymer concentration. Thermoplastic polyurethane dissolved in tetrahydrofluran was used as a solution. The results provide some insight into the effect of electrospraying process parameters on Jet Length
Preparation of Rigid Flame Retardancy Polyurethane Foam Material with Difficult Combusted Degree
Authors: Qiu Zhen Hui , Sun Yuan Bao , Du Zhan He
Published: June 2012

The flame retardants used for the rigid PU foam material were studied systematically in this paper and a series of experiments were carried out to test the oxygen index (OI) of it. The synergistic effect in the different flame retardants also be verified to achieve a well flame retardancy performance. The best ingredients were found out by an orthogonal experiment which can give the PU foam maeterial a difficult combusted degree with the oxygen index higher than 34.
Synthesis of Hydrophobic Modified Polyacrylamide Functional Materials in Supercritical CO2
Authors: Zheng Lan , Wang Yuqi , Dang Yin
Published: June 2012

The copolymerization of acrylamide (AM), Dodecafluoroheptyl methacrylate (G04), acrylic acid and the polycondensate of maleic anhydride and Polyethyleneglycol (PEG400) was studied in detail with benzoyl peroxide (BPO) as initiator when supercritical CO2 and the acetone solvent were presented. The functional fluoride hydrophobic associating polymer products have some special characters with excellent performance of gas storage The structure of the copolymer products was characterized by FTIR, MR, 1H-NMR and SEM analysis.
Research on Corrosion and Scale Inhibition Performance of HEDP
Authors: Li Mao Dong , Zeng Bin , Yang Lin , Zhao Jun Ming , Du Yu Hui , Zhang Hui , Zhu Zhi Ping
Published: June 2012

The static scale inhibition method will be used to evaluate the scale inhibition performance of HEDP. In order to study the corrosion inhibition of 20A steel with additive of HEDP in the industrial boiler water medium，the total iron ions in the solution are determined through autoclave static experiments. The results indicated that the scale inhibition efficiency，in the simulation boiler water with a certain concentration ratio and temperature，reached the maximum when CHEDP is 7 mg/L. It has a good corrosion inhibition effect on the 20A steel when the HEDP concentration exceeds 15ppm.
Shear Studies on Polymer Flooding Systems with High Concentrations
Authors: Wang Ji Gang , Wu Peng , Du Quan Qing , Cao Hui Hui , Sun Meng
Published: June 2012

Abstract: When the dose level of polymer is settled, the change of injection volume and concentration do not increase oil recovery obviously, while the result of lab research shows that the increasing of oil recovery of high concentration and high molecular weight polymer flooding can reach or over that of ASP flooding. The aim of this paper is to study the shear characteristic in high concentration and high molecular weight polymer flooding, and analyzed the suitable parameter of it.They can provide the theory of high concentration Polymer flooding. In the process of polymer flooding, it was because increasing the water phase viscosit and the retention effect of polymer molecules in porous media that making oil flow degrees than improved ,the sweep volume expand, and improve the oil recovery. Study confirmed [1-3], polymer solution with sticky elastic can effectively improve the oil displacement efficiency, reduce residual oil saturation [4-5]. So, the study on the shear properties of the polymer system in high concentration (>1000mg/L) can provide experimental base for a high concentration of polymer flooding, it also has important significance on theory of polymer flooding development and application research.
Analysis and Prediction of Damping Properties of Multi-Layered Organic Hybrid Materials Consisting of Polarized Polymers and Small Molecules
Authors: Ding Xin Bo , Liu Tao , Zhang Yan Hui , Han Jian
Published: June 2012

A theoretical study on damping properties of multi-layered hybrid materials was presented with the aim to obtain good damping materials with a broad and high damping range. The value of the multi-layered organic hybrid materials consisting of polarized polymers and small molecules was evaluated via the correspondence principle. Similarly, the damping properties of the multi-layered organic hybrid materials were predicted according to our previous work. With increasing the number of the layers of multi-layered hybrids, the temperature dependence of could be improved and it was almost rectangular transition range with values for the area under the linear curve. Therefore, it could be considered to be a new approach to improve the temperature dependence of the damping materials and obtain good damping materials with a broad and high damping range.
Capacitance Fading Induced by Degradation of Polyaniline: Cyclic Voltammetry and SEM Study
Authors: Zhang Hai Rui , Li Han Lu , Wang Ji Xiao
Published: June 2012

Polyaniline (PANI), one of the most studied conducting polymers (CPs), shows great promising application in supercapacitor in advanced power system. In present work, the capacitance fading of PANI nanofibers modified stainless steel (PANI/SS) electrode was investigated by combination of cyclic voltammetry (CV) and scanning electron microscopy (SEM). The kinetics of capacitance fading can be fitted to a second-order exponential decay. The fading rate constant of the capacitors increases by two orders magnitude when the upper-limit potential in CV increases from 0.55 to 0.80 V vs. SCE. We proposed that there are three factors leading to the capacitance fading, the first one is the hydrolysis of quinoid units in PANI produced during electrodeposition process or/and high potential applied, the second one is chemical degradation of PANI induced by the attack of solvated anions on nitrogen radical cation, and the third one is the electrochemical degradation of PANI which is due to the benzene radical cation. Additionally, the SEM images show that the morphology of newly formed PANI nanofibers are in gel structure, and become clear with the gel structure disappeared after 1000 cycles. Moreover, some regular particles appear at the electrode surface, which are supposed to be produced from the accumulation of the degradation product.
Ballistic Impact Testing and Analysis of Triaxial Braided Composite Fan Case Material
Authors: Liu Lu Lu , Xuan Hai Jun , Chen Guang Tao , Ye Dong , Hong Wei Rong , Xing Jun , Wang Jin
Published: June 2012

Abstract. Ballistic impact tests were preformed on triaxial braided composite panels using blade-like projectile in a way that approximates the impact velocity, deformation modes, and strain energy density at failure for composite fan case material during blade-out event. The failure modes are identified from impact test results. The main failure modes are fiber shear failure and matrix crush failure in the impact surface and fiber tensile failure, fiber pull-out, matrix cracking and delamination in the exit surface. Finite element model is developed to analyze the damage evolution of penetration process. It is found that the penetration process can be subdivided into 3 stages based on different damage mechanisms and the energy absorption mechanism in each phase is illustrated too.
Study on the Crystal Size of PCBM in Organic Photovoltaic Cells
Authors: Sun Nan Hai , Chang Xiao Ying
Published: June 2012

Phase separation of the poly(3-hexylthiophene) (P3HT) and [6,6]-phenyl-C61-butyric acid methyl ester(PCBM) active layer (ATL) was investigated by varying their relative ratio in the organic solar cells (OSCs).With the help of the UV/visible spectrophotometer, optical microscopy and scanning electron microscope,we found that the cluster of PCBM at the interface or surface was affected by Al cathode, the composition of the blends and thermal annealing. The disc-like shape crystals of PCBM substituted for the needle-like ones at higher PCBM compositions at the ATL/Al interface, which led to stronger contacts and bigger contact area. It could make short circuit current density increase, but may affect the blend morphology and result in parallel resistance and open circuit voltage decreased with the PCBM ratio increasing from 40 to 60%. The microstructure of the P3HT:PCBM ATL, determined by the composition dependent phase separation, supported the optimized performance of the OSCs with the composition of 40–50% PCBM.
The Optical and Structural Properties of InxGa1-XN/GaN Multiple Quantum Wells by Metal Organic Chemical Vapor Deposition
Authors: Han Li Jun , Ding Bin Feng , Lin Guo Man
Published: June 2012

The structural and optical properties of InxGa1-xN/GaN multi-quantum wells (MQWs) grown on sapphire are discussed. Two kinds of InxGa1-xN/GaN MQWs with same period and different single cycle thickness and different growth temperature of MQWs are selected. Firstly, from the result of SRXRD and RBS/C, we can estimate that indium content of InxGa1-xN /GaN MQWs is 0.033 and 0.056, the single cycle thickness of MQWs is 13.04nm and 15.86nm respectively. Secondly the PL results indicate the optical properties of InxGa1-xN/GaN MQWs. Finally, we find indium content decreasing with increasing growth temperature of MQWs and the emission intensity reducing with temperature increasing, the emission optical peak position versus temperature show the “S-shaped” character. All these experimental results testify the material design of InxGa1-xN/GaN MQWs will have potential applications in spectral LED.
Study on Ultrasonic Electroforming Ni-P Coatings on NdFeB Permanent Magnet
Authors: Li Li , Cheng Xiang , Yin Feng Shi
Published: June 2012

In order to improve the corrosion resistance of sintered NdFeB magnet, experiments are done by the new process which involves ultrasonic electroforming Ni–P alloys. The influence of ultrasonic on electroforming Ni–P alloy on NdFeB was studied by using microscope, adhesion test and NaCl solution immersion test.The results showed that the Ni–P alloy deposit on NdFeB is rough and has poor adhesion without ultrasonic agitation; However, the Ni–P alloy deposit on NdFeB with ultrasonic agitation has the following advantages: uniform and smooth deposit grains, strong adhesion and good corrosion resistance.
Upconversion Luminescence Property of Nanocrystalline Y2O3:Pr3+,Yb 3+
Authors: Hu Dan , Zhou Yong Qiang , Dai Ruo Nan , Chen De Shuai , Cai Guo Dong , Li Wang Zi , Li Si Cen , Li Pei Lu
Published: June 2012

The upconversion luminescence nanocrystalline powders Y2O 3:Pr 3+ ,Yb 3+ were prepared by co-precipitation method and characterized by X－ray diffraction,fluorescence spectrum and so on. Its luminescence property and the effect of different calcining temperatures and rare-earth ion doped concentration on its luminescence property were discussed. The results show that the nanocrystalline powders calcined at 800-1200 °C for 2h has a single crystalline phase -the solid solution cubic system phase of Y2O 3. There is a upconversion luminescence phenomenon in the powders doped 1%(mol percent) Pr 3+ . The powders excited by a 980 nm laser diode emit weak green fluorescent observed by naked eye. The upconversion luminescence of Pr 3+in Y2O 3:Pr 3+ ,Yb 3+ is obviously different that of Pr3+in other materials.There are two stronger emission zone in upconversion emission spectra of the powders in the 400nm-800nm range,whose center wavelength value are respectively 551nm, 762nm.Increasing the calcining temperature of the samples from 1000°C to 1200°C, the emission peak intensity sharply elevates.
The Effect of Environment on Photovoltaic Module Efficiency
Authors: Jafari Fesharaki Vahid , Arbaban Iman , Jafari Fesharaki Javad , Jomardi Mohammad
Published: June 2012

As a great potential renewable energy source, solar energy is going to become one of the most important energies in the world. Recently, there has been an enormous increase in the understanding of the operational principle of PV tools, which led to a sudden increase in the power conversion efficiencies of such tools. Solar modules vary under temperature changes and the change in temperature will affect the output power modules. In this paper a relation between efficiency, sun radiation and temperature is used and under cloudy climate is simulated so we can obtain desired efficiency by adjusting temperature around PV module.
Theoretical Study on Electronic Structures and Spectroscopic Properties of Indene-C60 Monoadduct (ICMA)
Authors: Xu Zhan Chun , Zhang Hong Sen , Li Zhe , Yang Xue Shun , Zhang Gang
Published: June 2012

ICMA and its derivatives, high performance acceptor of polymer solar cells, have received most attention in experimental and theoretical studies. In this work, we calculated electronic structures and spectroscopic properties of the ICMA by density functional theory (DFT) using B3LYP method. The geometrical structure data show that indene has little influence on C60. In comparison with [6,6]-phenyl C61-butyric acid methyl ester (PCBM), It was proved theoretically that ICMA possesses a better photovoltaic performance and higher LUMO energy level. ICMA and its derivatives could be a promising new acceptor which further improve the power conversion efficiency of the high performance polymer solar cells. The research indicates that the frontier molecular orbital are mainly localized on the C60 sphere, which shows carbon number of cage is an important factor leading to the change of optical and electrical properties. The present study provides theoretical supporting for further application of the ICMA and its derivatives in molecular design and structure-activity relationships research.
An Investigation of Half-Metallic Ferromagnets Behavior in Hg2CuTi-Type Heusler Alloy Ti2FeAl by Using GGA
Authors: Yang Xiu De , Wu Bo , Zhang Song
Published: June 2012

By using generalized gradient approximation (GGA) scheme within the density functional theory (DFT), the electronic and magnetic properties of Hg2CuTi-type Heusler alloy Ti2FeAl were investigated. The results reveal that a 100% spin polarization appears at Fermi level (εF) in Ti2FeAl, and is maintained during lattice range of 5.1Å~6.2Å. Ti2FeAl is one of stable Half-Metallic Ferromagnets (HMF) with a spin-minority gap of 0.5 eV at εF and total magnetic moment of 1μB per unit cell. Our studies also indicate that the competition between RKKY-type indirect exchange and direct hybridization of d-electronic atoms plays a dominating role in determining the magnetism.
Effect of Nb Doping on Electronic and Magnetic Properties of Heusler Alloy Ti2NiAl with Hg2CuTi-Type Structure
Authors: Chen Ying , Wu Bo , Chen Hong
Published: June 2012

In this work, the electronic and magnetic properties of Nb-doped full-Huesler alloy Ti2NiAl with Hg2CuTi-type structure have been investigated by using first-principles calculations within the density function theory (DFT). Due to the Nb which has less valence electrons than Ni doping into Ni-site, the gap around the Fermi level of the compound Ti2Ni1-xNbxAl (0≤x≤1) is gradually narrowed, and destroyed completely as x≥0.5. With the increase of x, it has gone through the transition from the ferromagnetism to the non-magnetism, and then to the ferromagnetism finally. Further analyses of density of states reveal that the d-electronic rehybridization induced by Nb-doping and RKKY-type indirect interaction is directly responsible for the changes of half-metallicity and magnetism.
Research on the Relationship between the Spray Overlap Width and the Photoresist Film Thickness and Uniformity
Authors: Qu De Gang , Xiang Dong , Mou Peng , Wang Han , Gong Ying Li , Liu Nan
Published: June 2012

Because of its small average droplet size, low carrier gas flow rate and the droplets not easy to splash etc, the ultrasonic atomizing spray technology is particularly suitable for making photoresist films. In order to get a reasonable spray scan interval, the parabolic deposition model was used to study the relationship between the spray overlap width and the photoresist film thickness and uniformity, and it can be concluded that the thickness of the film increases and the thickness variance of the film decreases oscillatorily along with the increasing of the spray overlap width.To obtain good uniformity of the photoresist film, the dimensionless overlap width should be at least greater than 0.15.
Research on Composite Powder and Magnet Properties of Bonded NdFeB Magnets
Authors: Qin Wan Zhong , He Jie , Meng Jia Hong
Published: June 2012

The injection molding of magnetic powder could cost-effectively mass-produce net shape magnets. The manufacture technology and properties testing method of composite powder and bonded NdFeB magnets from injection molding were described in detail. The effects of content of binder, additives and magnetic powder on the magnetic property, mechanical property and fluidity of injection molding magnets were investigated. Furthermore, the effect mechanism was revealed microcosmically. The injection molding bonded magnets were prepared by using the MQP-B rapidly quenching NdFeB magnetic powder and polyamide 12. The magnetic properties are: Br=0.539T, Hcb=345.37kA/m, Hci=681.02kA/m, and (BH)max=47.37kJ/m3.
Synthesis and Characters of Fe3O4/AMPS Magnetic Composite Material
Authors: Hou Xiang Yu , Hou Chun Yang , Zhang Zheng , Wang Wei Zhen , Gao Li Li , Wang Jing , Gao Xiang , Cui Zhen Dong
Published: June 2012

The synthesis of Fe3O4/AMPS magnetic composite material by solution polymerization method is introduced in this study. Results of structure, morphology and magnetic properties show that the solution polymerization technology is an effective method for synthesizing core-shell structure oxide/polymer magnetic composite material. The Fe3O4 prepared by chemical precipitation process is uniform nanoparticle and the size is about 10 nm. The synthesized Fe3O4/AMPS is large irregular nanoparticles, and the average diameter is about 30 nm. The FT-IR analysis suggests that electrostatic adsorption of probably contribute to the formation of core-shell Fe3O4/AMPS magnetic composite. The product Fe3O4/AMPS performs a typical superparamagnetic property with an absence of hysteresis in the M–H loop, implying a broad prospects of its potential application as target material.
Optimization of the Two Parameters of Classical Blaze Grating in Littrow Mount
Authors: Zhang Shan Wen , Ying Jian Xin
Published: June 2012

On the base of electromagnetic theory of gratings, we analyse the effects of both of two important parameters of classical blaze grating in Littrow mount to diffraction efficiency, and the two parameters are optimized for obtaining highest diffraction efficiency. It is presented that not only blaze angle but apex angle affect diffraction efficiency. The investigation has been performed on the design and fabrication of classical blaze grating which has high diffraction efficiency.
The Research Progress of Embedded Solid Lubricant Materials
Authors: Ding Yang , Song Peng Yun
Published: June 2012

Embedded solid lubricant materials have good self-lubrication characteristics, which can realize lubrication in special some situations such as low-speed, high-load, high-temperature of the machinery without lubricating oil or grease. This paper presents a review concerning the structure of embedded solid lubrication materials, and its lubricating mechanism, the development of embedded solid lubricant materials, the latest research progress of the influence factors such as different types of metal substrates, mosaic, temperature, load, and porous structure and the application example of bearings. The feasibility of embedded solid lubrication materials which may be used in the mechanical seal face is also analyzed.
Synthesis and Properties of Acrylate Modified Waterborne Polyurethane Emulsion
Authors: Fei Liang
Published: June 2012

Acrylate modified waterborne polyurethane (PUA) emulsion was prepared by means of core-shell polymerization processes. The structures and properties of emulsions were characterized by FTIR, TEM and DSC. The effects of polymerization temperature, the type and amount of initiator and the acrylic amount on the properties of emulsions were investigated. The experimental results showed that the emulsions prepared were core-shell composite, when the polymerization temperature was 70~75 °C, using oil-soluble initiator azobisisobutyronitrile (AIBN), and the percentage of AIBN was 2.0%~ 2.5%, the properties of the emulsion can be better, and the water resistance, stability and mechanical properties of the PUA films were improved increasingly.
Density, Microstructure and Mechanical Property of Large-Scale C/C Composites Prepared by Thermal Gradient CVI
Authors: Cao Wei Feng , Li He Jun , Guo Ling Jun , Li Ke-zhi , Deng Hai Liang
Published: June 2012

2D-C/C composites with the dimension of Φ80mm×400mm were prepared rapidly by thermal gradient CVI within 104 hours. Their density reached 1.74g/m3 and the density difference was less than 0.04g/cm3. The pyrocarbon microstructure changed from RL to RL+SL, and then to SL along radial direction. These changes were attributed mainly to the difference of gas concentration and temperature gradient at every micro-zone during chemical vapor infiltration. After heat-treatment at high temperature, the space among layers of pyrocarbon enlarged and residual thermal stress was freed, which could lead to cracks formed in matrix. The flexural property of composites decreased with increasing heat-treatment temperature and the fracture mode changed from the brittleness to pseudo-plastic. Carbon particulars between pyrocarbon laminas can increase the flexural strength by particular reinforcement.
Using Paper as Reinforcement in Silty Sand
Authors: Chegenizadeh Amin , Nikraz Hamid
Published: June 2012

Reinforced soil has been among the most effective soil modification materials. Its use has been expanded rapidly into civil engineering, geotechnical engineering and pavement engineering. Reinforcing subgarde in pavement systems has always been an issue. This study focuses on effect of paper inclusion on the modulus of elasticity of subgrade material. Paper was used for this investigation. Paper contents and aspect ratio have been changed during these tests. The paper percentage varied from 0 % (for unreinforced samples) to 20%. Silty sand was used as sub grade material. Unconfined compression tests were carried out to investigate behaviour of the composite under different condition. The paper reinforcment length and paper reinforcment content found to play important rule on the modulus of elasticity of paper reinforced samples. Furthermore it was observed that ductility of sample increased by paper inclusion.
Effect of Multi-Material Substitutions on Static and Dynamic Properties of Electric Vehicles
Authors: Yu Li Li , Su Zhen Hua , Lin Jing Zhan , Yuan Yu Sen , Cui Chun Xiang , Yu Ling
Published: June 2012

Automotive weight reduction is a challenging task due to many performance targets that must be satisfied simultaneously, in particular in terms of static and dynamic properties direct relating to strength, stiffness and NVH characteristics of vehicles. Compared to all-steel vehicle frame, multi-material substitutions are adopted in each structural component for higher product performance and a lightweight electric vehicle frame in this paper. The SHELL63 element is selected to construct finite element (FE) model of vehicle frame based on the FEA software ANSYS. Under full bending loading and torsional loading respectively, static analysis of frame is performed, and the strength and stiffness are evaluated as well. The Block Lanczos is adopted for dynamic analysis of vehicle frame. Their first eight modal properties are obtained and far away exciting frequency range of rough road. The multi-material vehicle frame has been designed to be made of mild steel, aluminum and magnesium alloys. Its static and dynamic properties show that the strength, stiffness and NVH characteristics are better than ones from all-steel vehicle frame with weight reduction of 31.7%. These procedures will help to design a lightweight and thus to provide technical support for reducing fuel consumption and greenhouse gas emissions.
Non-Isothermal Crystallization Behavior of Poly(trimethylene Terephthalate-Co-Isophthalate) Copolyesters
Authors: Shyr Tien Wei , Tung Chia Hsin , Liu Yan Ting
Published: June 2012

Poly(trimethylene terephthalate-co-isophthalate) (TI) copolyesters were synthesized using different ratios of isophthalic acid (IPA) and Terephthalic acid (TPA) with 1,3-propanediol (1,3-PDO). The compositions of TI copolyesters were analyzed using 1H nuclear magnetic resonance (NMR). Non-isothermal melt- and cold-crystallization and subsequent melting behaviors were investigated using differential scanning calorimetry (DSC). For TI0, TI10, and TI20, non-isothermal crystallization kinetics were analyzed using a modified Avrami equation. The results show that the reaction rate of TPA with 1,3-PDO was similar with that of IPA with 1,3-PDO in TI copolyesters. Crystallization exothermic peak and melting endothermic peak were not observed in DSC traces with an increase of the relative amount of PIP to 41%. The Avrami exponent n is in the range of 3.5-4.2 for melt-crystallized TI copolyesters and between 3.0-3.2 for cold-crystallized copolyesters. It suggests that the crystallization from melt state corresponds to thermal nucleation but the crystallization from glassy state originates from predeterminated nuclei.