bluuebunny/crossref_metadata_2025 huggingface dataset:
Fluiding Characteristics of Pulverized Coal in Fluidization & Injection Jar
Authors: Song Chun Yan , Gui Yong Liang , Shi Yan , Hu Bin Sheng
Published: December 2011

The fluiding characteristics of pulverized coal in fluidization & injection jar were studied systematically with the conveying property testing equipment of pulverized coal designed by ourselves. Results show that the fluidization process of pulverized coal in fluidization & injection jar is a progressive process. The necessary condition of fluidization for pulverized coal in fluidization & injection jar is that the actual fluiding velocity exceeds the theoretical fluiding velocity. According to the moving state of pulverized coal particles in fluidized and injection jar, the fluidization process of pulverized coal consists of three stages of static bed, fluidization bed and gas flow bed.
Study on Cavitation Mechanism of Pulse Electrochemical Compound Machining
Authors: Zhang Cheng Guang , Zhang Fei Hu , Zhang Cheng Guang
Published: December 2011

According to this theory, the cavitation mechanism of ultrasonic-pulse electrochemical compound machining (UPECM) based on particle impact is proposed in the paper. The mechanism was studied particularly, and validated by experiments. The results show that ultrasonic cavitation promote pulse electrochemical compound machining, and particle impact has the catalysis of the anodic dissolution in the ultrasonic-pulse electrochemical compound machining. The results also indicate that the processing velocity can be improved under the particle impact, obtaining the surface quality in UPECM compound machining.
Controlled Release of Tablets Containing Poorly Water Soluble Model Drug Coated with Kollicoat MAE 30DP
Authors: Lemke Stefan , Kumpugdee-Vollrath Mont
Published: December 2011

In this project we have prepared the tablets with a coating of pH-sensitive polymer Kollicoat MAE 30DP. For this purpose the core tablets prepared from poorly water soluble model drug and other excipients were coated by a fluidized bed apparatus at the exhaust air temperature of 30°C and spraying rate of 0.55 g/min. The highest coating time was 384 min which leads to the film thickness of 648 µm. The coated tablets were gastric resistant for one hour and resistant against intestinal fluid pH 6.8 up to 70 min. The coating film has a good quality with smoothness and dense packing. However, if the thickness was high e.g. 600 µm the film surface had more wavy structure. The results served to formulate the colon delivery system.
Modal Analysis of the Hydraulic Retarder Shell
Authors: Zhao Xu Fei , Li Chang You , Li Xiao Wen , Xu Feng Ying , Mai Zhi Wei , Qiu Yu
Published: December 2011

The 3D model of THB40 hydraulic retarder shell was established which was based on the Pro/E modeling software. The model was simplified and was introduced to ANSYS Workbench as FEA model by ANSYS-Pro/E data interface. The constraints were imposed on the FEA model for the preceding six modal analysis. The former 6 order natural frequencies and the biggest resonance deformation is obtained to determine whether there are some vibration forms which have unfavorable effects on the vehicle and to avoid resonance phenomenon to appear. At the same time, it provides the reference for the further research of the vibration mechanism of the structure and the vibration suppression technique for practical application.
Hedonic Price Analysis on Mobile Phone Market
Authors: Zhang Xiao Hong , Fu Li You , Zhang Hang
Published: December 2011

Using collected 190 samples, this paper studied Chinese mobile phone market with hedonic price analysis. Through calculating hedonic price of heterogeneous goods, this paper summed up the positive and negative factors that influence the price of mobile phones. This paper found that network type and GPS are negative effects on mobile phones’ prices, which is little different from the real life situation; And the price will become more and more cheaper with time; In addition, the price of mobile phones with additional features is correspondingly higher.
Design and Development of Non-Ironing Fabric of Cotton/Fractal Polyester Twisted Yarn
Authors: Zhang Jun Ying
Published: December 2011

The main properties of fractal polyester filament are described , the process of the research and development of cotton/fractal polyester twist yarn and it’s fabric is explored. The tensile strength , anti-pilling tendency and iron-free properties of the fabric of cotton/fractal polyester twist yarn are qualified .The product has a wide application prospect and can be used for high grade shell fabric.
Impregnation of Ru(cod)(tmhd)2 into PDMS Film in Supercritical Carbon Dioxide
Authors: Ge Ming Lan , Ding Fu Chen , Erkey Can
Published: December 2011

Metallopolymer nanocomposites has attracted much attention recently. The impregnation of organometallic compound from the supercritical solution into the polymer matrix has several advantages. The impregnation process isotherm of bis(2,2,6,6-tetramethyl-3,5-heptanedionato) (1,5-cyclooctadiene) ruthenium (II) (Ru(cod)(tmhd)2) into polydimethylsiloxane (PDMS) film in supercritical carbon dioxide (scCO2) was investigated. The experiments for determining the isotherm were carried out at 40 °C and 10.34 MPa. It was found that the impregnation isotherm is linear up to the saturation concentration of the precursor in scCO2 fluid phase. The slope of the linear curve defined equilibrium partition coefficient K provides a measure of the partitioning of Ru(cod)(tmhd)2 between the PDMS film and scCO2 fluid phase and it is constant under the same conditions. It showed that K is mainly govered by the density of scCO2 and does not change much with temperature at a constant density of scCO2.
Contributions of Microorganisms to Nitrogen Cycle of Wuyiling Wetland in Yichun in Northeast China
Authors: Li Ji Guang , Ren Yi Bin , Ren Nan Qi , Yang Chun Wen , Zuo Chun Sheng , Jin Zhi Min , Shao Yan Qiu
Published: December 2011

Wetland is the important part in urban ecosystem. Microorganisms is integral component of urban wetland ecosystem is the main factor of wetlands sewage treatment, and plays an irreplaceable role in the degradation. In this paper, the authors regard urban wetland of Yichun in north shore of Tangwang river as the research object, through experiments to identify the microorganisms types, finding five microorganisms types being nitrify fungi. The article analyzes the contributions of microorganisms in nitrogen cycle of urban wetland. It is present that microorganisms plays an irreplaceable role in controlling pollutions and nitrification and anti-nitrification reactions play the most significant role in the degradation of nitrogen compounds and ammonium oxidation is a possible process in deducing nitrogen pollutions.
Effect of Chlorination Conditions on Amount of THMs
Authors: Li Ji Guang , Sun Hui , Yang Chun Wen , Shao Yan Qiu , Jin Zhi Min , Zuo Chun Sheng , Ren Nan Qi , Yuan Yi Xing , Zhang Tu Qiao
Published: December 2011

Experiment was made，in which Harbin reservoir water was taken as source water to observe the influence of chlorination conditions such as chlorine dosage，reaction time，pH value，organics concentration and varieties of disinfectant on the amount of THMs formation．Based on the experiment results，control measures were proposed for the formation of disinfection byproducts such as THMs through optimization of disinfection．
Fabrication of NiTi Alloy Coating on 2Cr13 Stainless Steel by Laser Cladding
Authors: Zhang Chun Hua , Li Shuang , Qi Lin , Ren Yu Hang , Zhang Song , Wang Mao Cai
Published: December 2011

A systematic study of the cladding NiTi alloy on 2Cr13 stainless steel by plused Nd-YAG laser has been conducted. The geometry and microstructure of the clad layer are studied by optical microscopy and scanning electron microscope, respectively. The phase composition of cladding layer is analyzed by X-ray diffraction, and its hardness distribution along the depth of the clad layer is measured by microhardness tester. The results show that, with the augmentation of current, the height of clad layer decreases but that the width and clad angle increase. Three typical microstructures (B2 phase+tetragonal structure of precipitates, dendrites and grains) are precipitated in the NiTi alloy during rapid solidification. The average microhardness of the clad layer in C-2, C-4 and C-5 samples are about 670HV, 700HV and 615HV, respectively.
Enhanced Corrosion Resistance and Damping Capacity of As-Cast AZ91 Magnesium Alloys with Ce Addition
Authors: Wan Di Qing
Published: December 2011

Through the weight loss experiment in 3.5%NaCl solution, the effect of Ce contents on the corrosion resistance of AZ91 magnesium alloy was carried out. In addition, the damping performance of Ce added AZ91 alloys were also studied. The result shows that adding Ce can significantly improve the corrosion resistance and damping capacity of AZ91 magnesium alloy; the grain refinement and secondary phase morphology modification can contribute to those properties improvement.
The Influence of Thermal Exposure on the Microstructure Evolution of a Nickel-Base Single Crystal Superalloy
Authors: Jia Yu Xian , Jin Tao , Liu Jin Lai
Published: December 2011

Microstructure evolution of a nickel-base single crystal superalloy on the [001], [011] and [111] orientation during thermal exposure at 1000°C was investigated. The SEM studies revealed that the size of γ' phase increased and some of which linked together with the elongation of the exposure time. After 1100h the cubic γ' phase hardly is observed, and the rafting structure becomes perfect. With growing and linking of γ' phase the γ matrix channel is widening gradually, and the direction of γ' rafts is not along one define orientation. The TCP phase is not found in the three oriented samples during the thermal exposure.
Study on the Structure and Phase Transition of Sm Substituted BiFeO3 Nanoparticles
Authors: Sun Yu Xia , Zhang Xing Wen , Liu Hong Ri
Published: December 2011

Pure and Sm substituted BiFeO3 nanoparticles were prepared by a coprecipitate method using Bi(NO3)3•5H2O and Fe(NO3)•9H2O as raw materials. X-ray diffraction pattern indicates that perovskite structural BiFeO3 can be obtained using 0.02 molar precursor precipitate by annealing at 550 °C. A structural phase transition deduced by Sm substitution was observed. SEM results showed that the size of BiFeO3 increases with annealing temperature and substitution ratio. DTA results showed that the phase transformation temperature decreases with Sm substitution ratio.
Thermal Performance and Dehydration Kinetics of KAl(SO4)2•12H2O as Phase Change Material
Authors: Dai Jian Feng , Ling Run Qiang , Wang Ke Zhen
Published: December 2011

The dehydration kinetics of phase change material KAl(SO4)2•12H2O was studied under non-isothermal conditions and the Kissinger’s method was applied to analyze the TG and DSC data in order to calculation of activation energies and pre-exponential factors for different heating rates. It was concluded that dehydration of KAl(SO4)2•12H2O occurred in three steps. The activation energies and pre-exponential factors were calculated as 95.9 kJ/mol and 1.95×1010min-1 for step I, 128.8kJ/mol and 3.67×1012 min-1 for step II, 159.6kJ/mol and1.92×1013min-1 for step III, respectively. In addition, various materials have been tested to prevent the KAl(SO4)2•12H2O supercooling.
Convenient Hydrothermal Synthesis of Zeolite a from Potassium-Extracted Residue of Potassium Feldspar
Authors: Su Shuang Qing , Ma Hong Wen
Published: December 2011

Zeolite A was successfully synthesized via convenient hydrothermal process using potassium-extracted residue of potassium feldspar as a combined source for silica and alumina. Optimization studies on the molar ratios of Na2O/SiO2 and H2O/SiO2, and aging time have been conducted. The results were that pure zeolite A with high crystallinity could be synthesized when the reaction mixture with molar ratios of Na2O/SiO2 and H2O/SiO2 of 2.0 and of 85, respectively, were crystallized at 100°C for 3h. Aging was found to be not prerequisite for the formation of zeolite A in the system. The product was characterized by XRD, FTIR, SEM and calcium exchange capacity. Finally, a comparative study of the zeolite A formation from the potassium-extracted residue and other industrial waste or natural silicate minerals was also carried out.
Electrochromic Properties and Raman Spectroscopy Analysis of Tungsten Oxide Thin Film by RF Sputter
Authors: Cheng Chin-Pao , Lin S.H.
Published: December 2011

This study utilizes tungsten oxide as the research subject and investigates changes between different argon/oxygen gas flow ratio and deposits on ITO substrates through RF reactively sputtering. Propylene carbonate (PC) is further mixed with LiClO4 for the preparation of electrolyte. After packaged into components, electric voltage is applied to the films to generate reduction or oxidization, which can obtain different colored/bleached states. Lastly, Raman spectroscopy analysis is performed to get a greater understanding of electrochromic mechanisms. The results of the experiment discovered that as-deposited tungsten oxide thin film shows the formation of W+6 states, and the application of driving voltage causes the formation of W+5 states. At the same time, the thin film coloring effect appears. Increases in driving voltage cause the gradual conversion of W+ 6 states into W+5 states, which further leads to a more significant coloring effect. On the other hand, W-O-W deformed crystal lattice structures are also produced, which also affects the incidence of electrochromic property.
A Modified Coupling Method to Solve the Integrated Equations of Velocity and Temperature Fields in 3D FEM
Authors: Song Shu Ni , Liu Jing Yi , Liu Xianghua , Li Chang Sheng
Published: December 2011

During the rolling process, temperature is an important factor that affects the die and the work-piece in metal forming procedure. The metal deformation is often carried along with the variety of temperature. Moreover, mechanical energy of plastic deformation is converted into heat during the metal deformation process. Thus, it is necessary to couple the deformation and thermal behaviors in an integrated manner in numerical simulation so as to improve the simulation accuracy. In this paper, we use a 3D rigid-plastic Finite Element Method (FEM) to simulate the hot rolling process by coupling the thermal effects. Based on the 3D FEM model, integrated equations of coupling velocity and temperature fields are formulated. The uniform of integrated equations is obtained by re-indexing the combination sequences and then a modified coupling method is proposed to solve the resulted equations. The numerical experiments are carried on the real data collected from a steel plant. A good agreement between the numerical result and measured value shows the availability of the proposed coupling method.
Evaluation of Relations among Basic Mechanical Properties of Concrete with Machine-Made Sand
Authors: Li Feng Lan , Zeng Yan , Li Chang Yong
Published: December 2011

Due to many different characteristics such as irregular polygon particle with pointed edges, rough surface and larger content of stone powder, machine-made sand has ignorable effects on the properties of concrete. As the basis for the design of concrete structures, the relations among the basic mechanical properties of concrete such as compressive strength, tensile strength, flexural strength and elastic modulus should be clearly understood. This paper summarizes the test data from the published references, and discusses the relations among these properties by statistical analyses compared with those of ordinary concrete. The results show that the axial compressive strength and the tensile strength can be prospected by the same formulas of ordinary concrete specified in current Chinese design code, but the prospected tensile strength should multiply a reducing coefficient when the strength grade of concrete is lower than C30. The elastic modulus of concrete with machine-made sand is larger than that of ordinary concrete, which should be prospect by the formula in this paper. Meanwhile, the formula of flexural strength is suggested.
Electrochemical Study on the Effect of Xanthine on Electrodeposition of Nanostructured Pt Thin Films and Pt(IV)-Xanthine Interaction
Authors: Pan Hong Cheng , Liu Jiang Tao , Liu Wei Hong , Li Xue Peng , Liang Guo Xi
Published: December 2011

Nanostructured Pt thin films were electrodeposited in the presence of varying amounts of xanhtine. The electrodeposited Pt films exhibit different catalytic efficiency for methanol electro-oxidation. The anodic current of methanol decreases linearly with the increase of xanthine during the electrodeposition. The effect of xanthine on the catalytic efficiency of Pt films was studied by cyclic votlammetry (CV) and differential pulse voltammetry (DPV). The results of CV and DPV reveal the formation of a 2:1 complex between Pt(IV) and xanthine. The conditional stability constant of the complexes was determined to be 3.8×106.
Fabrication of Unfired Porous Quartz Brick Used the River Sands from the Yangtze River in China
Authors: Song Jie Guang , Wang Fang , Du Da Ming , Li Yang Liang , Ji Gang Chang
Published: December 2011

The insulating brick is prepared used low grade quartz sand along the Yangtze River, and the mechanism of porous structure contolment is researched, which lay technological foundation for increasing the performance of insulating brick. The results show the porosity of unfired porous quartz bricks is decreased with increasing the content of quartz sands. When the content of foaming agent is beyond 0.5%, the porosity of unfired porous bricks is increased with increasing the content of foaming agent. When the ratio of materials and water is above 1:1.1, the porosity of unfired porous bricks is decreased with increasing the content of adding water. Through optimizing the technology that using 60% quartz sands, 39% cement, 1% foaming agent and the ratio of materials and water for 1:1.1 are mixed, the unfired porous quartz bricks is produced, the density is 0.628 g/cm3, the porosity is 74.586% and the compression strength is 1.9 MPa, the porous structure of brick is homogeneous distribution, the pore is closed pore.
Stress Analysis of Laminated Glass under Uniform Lateral Pressure
Authors: Pang Shi Hong , Ma Juan Rong , Ma Zhen Zhu , Wang Li Chuang
Published: December 2011

The shear modulus of PVB and SGP interlayer is analyzed. With the same conditions of load duration and temperature, the shear modulus of SGP interlayer is about fifteen times than that of PVB interlayer. A finite element model of laminated glass is established in this paper. The simulation results show that the maximum principal stress contours of PVB laminated glass change from a circular to a petal-shaped one and those of SGP laminated glass change form a quadrangular to a square-shaped one when the temperature rises from 20 degrees Celsius to 50 degrees Celsius.
Effect of Compression Ratio and Lay Angle of Metal Net on the Mechanical Properties of Metal Net-LVL Composite
Authors: Li Jin , Hu Ying Cheng
Published: December 2011

In order to improve the mechanical strength of LVL, metal net was inserted into the LVL (metal net-LVL composite) made of fast-growing poplar. In this study, the effects of compression ratio and lay angle of metal net (which is lay angle for short in this paper) on the mechanical properties of the metal net-LVL composite was investigated in a comparative way. In order to find out the optimum compression ratio and lay angle, the modulus of rupture (MOR), modulus of elasticity (MOE) and horizontal shear strength of the metal net-LVL composite were tested. The results showed that the effects of the compression ratio on MOR, MOE and horizontal shear strength were significant, with increasing of compression ratio, the values of MOR and MOE showed an earlier raised and later decreased state, and had the maximum values at 31%. The effects of lay angle on MOR and MOE were significant, the values of MOR and MOE increased first and then decreased with lay angle increasing, and the maximum values were obtained at 20°, though there were no significant effects on horizontal shear strength, there were the maximum values at 20°. Therefore, when the compression ratio was 31% and the lay angle was 20°, the metal net-LVL composite could obtain the optimal overall mechanical properties.
Finite Element Simulation of Perfect Bonding for Single Fiber Pull-Out Test
Authors: Wei Gao Feng , Liu Guo Yong , Xu Chong Hai , Sun Xiao Qiang
Published: December 2011

In this paper mechanical behavior of the interfacial perfect bonding between fiber-matrix composite is analyzed using a pull-out test based on the finite element simulation. The finite element method is used to calculate the interfacial stress and deformation distribution of single fiber reinforced resin matrix specimen. The transfer process of the shear stress along the fiber interface and the distribution patterns of the shear stress are studied. These results are useful to be able to predict effects on the stress transfer properties across the interface and the interfacial debonding behavior.
Photocatalytic Activity of Bi2O3 Prepared by Different pH Value
Authors: Lu Yan , He Xi Yang , Zhong Jun Bo , Li Jian Zhang , Hu Wei
Published: December 2011

Abstract. Bismuth oxide is an important metal-oxide semicondutor, the interest in developing methods which can prepare Bi2O3 with unique properties has been a hot issue recently. In this paper, paralled flaw precipitation method has been employed to synthesize nanostructured Bi2O3. It is found that the bandgap and photocatalytic performance of Bi2O3 has a strong dependence on the pH value of precipitation reaction.The prepared photocatalysts were characterized by BET, XRD and UV-Vis diffuse reflectance. The results show that Bi2O3 prepared under pH value 8.5 has the highest BET surface area, pore volume, the smallest pore size and the average crystal size. Bi2O3 prepared under pH value 8.5 exhibits the best photocatalytic activity. The results of further experiments show that bandgap and the specific surface area all play an important role in promotion of photocatalytic activity of Bi2O3 prepared under pH 8.5.
Study on Influence of Modified SiC Nano-Powders on the Microstructures and Work-Hardening Properties of ZGMn13
Authors: Yang Jun , Chen Mei Ling , Yang Li , Jin Huan , Gao Hong
Published: December 2011

The effects of modified SiC nano-powders on the microstructures and the work-hardening properties of shot peening treatment on high manganese steel have been carried out by means of microstructure observation, x-ray diffraction analysis and hardness testing. The results are showed that compared with the samples without modified SiC nano-powders, the microstructure of ZGMn13 are finer and markedly improved rate of work hardening. The micro-hardness of surface is enhanced significantly after the shot peening. Its strengthening mechanism is mainly twinning and dislocation, but no Martensite strengthening.
A Comparative Study of Monomers on the Preparation of Permselective Functional Packaging Materials
Authors: Fu Ya Bo , Li Dong Li , Xu Wen Cai , Tian Xia Qing
Published: December 2011

Gas permselective packaging film is an emerging material which enables it with gas selective permeation functions so as to keep the preservation atmosphere of inner packages and thus extends the shelf-life of fresh fruits. In this work, Hexamethyldisilazane and Hexamethyldisiloxane were applied as the precursors to comparatively investigate the behavior on the preparation of gas permselectivy film, respectively. Also, Different reaction parameters such as plasma input power, deposition time and monomer proportions were investigated respectively. The film properties were analyzed by Water Contact Anglemeter, Surface Profiler thickness test, Fourier Transform Infrared Spectroscopy (FTIR), water vapor transmission rate test (WVTR) and oxygen transmission rate test (OTR). The results showed that HMDS is better than HMDSO to be the precursor for the formation of gas permselectivity films.The film formed from the monomer of HMDS changed the gas permeability of the film reversely which is more suitable for the preparation of such materials.
Influence of Adding Different Poly (ethylene glycol) in the Biosynthesis of Bacterial Cellulose
Authors: Liu Hai Fang , Feng Yu Hong , Yan Jin Ke , Zhang De La , Li Jia Cheng
Published: December 2011

Bacterial cellulose-poly (ethylene glycol) composites (BC-PEG) were biosynthesized by adding different molecular weight of poly (ethylene glycol) into Acetobacter xylimum culture medium. The obtained BC-PEG composites were characterized by scanning electron microscopy (SEM), thermogravimetry (TG), X-ray diffractometry (XRD) and tensile test. SEM images showed that the morphology of BC-PEG composites changed. TG results indicated their thermal stability also changed. XRD profiles suggested their crystalline morphology no much difference. But the tensile tests appeared that the adding of different molecular weight PEG modified the mechanical properties of BC-PEG composites.
Synthesis and Crystal Structure of the Cobalt (II) Complex with Mixed-Ligand
Authors: Yang Yan , Yan Liu Ting , Li Xiao , Qin Rong Huan , Duan Wen Gui
Published: December 2011

The Cobalt (Ⅱ) Complex constructed with 5-nitroisophthalic acid and 2,2’-bibenzimidazole, [Co(H2bibim)2( 5-nipa)] (1), (H2bibim =2,2’-bibenzimidazole, 5-nipa=5-nitroisophthalic acid) have been synthesized by hydrothermal methods and structurally characterized by elemental analysis, IR and X-ray single crystal diffraction. Complex 1 has six coordinated by two H2bibim ligands and one 5-nitroisophthalic acid groups that is further connected though intermolecular hydrogen bonds and resulting in a three-dimensional (3D) network.
The Development and Performance Evaluation of Green Cross-Linked Movable Gel
Authors: Li Cui Xia , Wen Guang Hua , Yang Jian Jun , Li Jian Guo , Zhou Yang Fan
Published: December 2011

Through laboratory experiments, a green cross-linked movable gel has been developed, which has been used for reservoir profile modification. The main agent of gel is hydrophobic associating polymer, concentration is 3000mg/L; the cross-linking agent is Aluminum citrate from complex of Aluminum ion and citric acid root ion. The best molar ratio of aluminum ions and citrate ions is 1.5:1 in complex reaction, the amount is 140mg/L; the retarder is tartaric acid sodium, the amount is 150mg/L; The stabilizer is thiourea, the amount is 800mg/L; The strength of the green cross-linked movable gel is 3.12×104mPa.s, gelling time 36h, Stable time 160d; It is suitable for low-temperature reservoir profile modification, and salt resistance is good. Laboratory experiments show that the green cross-linked movable gel have strong plugging capacity and improving profile ability. The green cross-linked movable gel has strong three dimensional network structure, which be observed through the environmental scanning electron microscopy.
The Effect of Uniaxial Stretching on the Crystallization Behaviors of Polylactic Acid Film
Authors: Xie Hui Li , Guo Kai , Chen Jin Zhou , Wang Wan Jie , Niu Ming Jun , Li Xin Fa
Published: December 2011

Abstract. The effect of uniaxial stretching of different stretching ratio at 80 °C, 90°C, 100°C, 110 °C and 120°C on the crystallization behavior of polylactic acid (PLA) film was investigated by using differential scanning calorimetry (DSC), wide-angle X-ray diffraction (XRD) and polarizing microscope (POM). The results showed that the crystallinity of PLA film was improved via uniaxial tensile orientation and increased with increasing stretch ratio, and the crystallinity of PLA film reached the maximum under the conditions of 90°C and stretching ratio 300%. Stretched PLA films show α crystal form. The spherulites deform to ellipsoids after stretching.
Fabrication and Properties of the PVDF/PVDF-g-PMMA Blend Hydrophilic Membrane
Authors: Yuan Tao , Meng Jian Qiang , Cai Guo Rong , Zhang Yu Feng
Published: December 2011

An amphiphilic graft copolymer was obtained via atom transfer radical polymerization (ATRP) of methacrylate (MMA) initiated directly by polyvinylidene fluoride (PVDF). Hydrophilic PVDF membranes were prepared by immersion precipitation of PVDF-g-PMMA and PVDF blend solutions. The chemical structure and the molecular weight were characterized by 1H-NMR and GPC. The hydrophilicity of membrane surfaces were characterized by static water contact angle. Top surface and cross-section of membranes were observed by Field Emission Scanning Electron Microscope (FESEM). The results demonstrated the water contact angle of the membrane surface decreased from 89°to 67°, indicating enhanced hydrophilicity; the pure water flux water firstly decreased and then increased up to 1.7 times of the PVDF membrane. The retention of PEG (Mn=6000) could be maintained at 93%-95%.
Characterization of Five Natural Resins and Waxes by Differential Scanning Calorimetry (DSC)
Authors: Zhang Ru Guo , Zhang Hong , Zhang Zheng , Zheng Hua , Feng Ying , Zhang Wen Wen
Published: December 2011

Thermal properties of 5 natural resin and wax samples (shellac, rosin, shellac wax, beeswax, Chinese insect wax) were examined by differential scanning calorimetry (DSC). The DSC melting and crystallization curves of the samples were presented in this paper. Three DSC parameters, To, Tf and ΔT (difference between To and Tf), were selected from each curve. Evaluation results of the parameters showed that they were statistically significant with individual excellent reproducibility. Information was provided by evaluation of changes among thermal absorption or release peaks of the curves in differentiating the five resins and waxes. It was demonstrated in this paper that DSC is rapid, convenient, reliable and accurate to qualitatively identify the resins and waxes mentioned above.
Theoretical Investigation of Energy Levels Splitting of CsCdBr3:Pr3+ Crystal
Authors: Duan Mei Ling , Yang Xiao Feng , Li Jin Hong
Published: December 2011

Based upon the single electron energy state information and the combination of Racah’s group-theoretical consideration with Slater’s wavefunctions, the 91×91 complete energy matrix of 4f2 configuration ion Pr3+ in C3v crystal field has been constructed. The calculated Stark energy levels of CsCdBr3:Pr3+ present a good agreement with the experimental values, which implies that the complete energy matrix method can be received as a recommendable tool to perform a theoretical analysis to the doped crystal. Besides, the influence of Pr3+ ions on the energy levels splitting of the host crystal CsCdBr3 has been compared with two doped trichlorides by Pr3+ ions, which indicates that the sixth order crystal field parameters play an indispensable role in splitting the energy levels.
Synthesis of Tung Oil Anhydride-Ester Polyol
Authors: Du Xun Jun , Sun Han Zhou , Wu Yu Xiong , Zhou Jin Hua , Tan Xiao Feng , Zhang Dang Quan , Zhang Huai Yun
Published: December 2011

Tung oil is a special biomass resource in China. Tung Oil has the characteristic to be transformed into serial derivatives for its active Conjugated double bond. Especially, tung oil anhydride-ester polyol (TOAEP) can be used as substitute of polyester polyol and/or polyether polyol in the synthesis and modification of polyurethane materials. Through esterification and transesterification, methyl-α-eleostearate-maleic anhydride adduct (MEMAA), a derivative of tung oil, was reacted with ethylene glycol and tung oil anhydride-ester polyol (TOAEP) was obtained. The optimal preparation condition are as follows: p-toluene sufonic acid is used as the catalyst, mole ratio of ethylene glycol to MEMAA is 4:1, reaction temperature is 120°C ~130°C, reaction duration is 8 h. Under the optimal preparation conditions, the yield of TOAEP is up to 88.8% and the hydroxyl value is up to 318.0 mg KOH/g. The structure of TOAEP was confirmed by Infrared spectroscopy (IR).
Photolithography and Photochemical Reaction of Copolymer Containing Anthracene in Langmuir-Blodgett Films
Authors: Xu Wen Jian , Li Tie Sheng , Zhao Gong , Wu Yang Jie , Miyashita Tokuji
Published: December 2011

A series of copolymer containing photoactive anthracene group, poly(N-dodecylmeth- acrylamide-co-anthrylmethylacrylate) p(DDMA-co-AnMA) were synthesized. Their molecular arrangement and photolithographic properties in Langmuir–Blodgett (LB) films were investigated. The copolymer p(DDMA-co-AnMA) could form stable monolayer at air/water interface and could be transferred onto solid supports, giving Y-type uniform LB films. The result showed that the irradiation with difference light wavelength leaded to changes of copolymer LB films in their chemical structure, concerning only the anthracence unit. When irradiated at 248 nm, the anthracene acted as photodecomposition group because of the peroxides. On the other hand, the main photoreaction induced by 365 nm is dimerization of anthracene. As a result, posotive-tone and negative-tone pattern could get by choosing a suittable irradiation light wavelength. Etching resistance of p(DDMA-AnMA) LB films was also investigated in a nanometer regime permitting etching of gold.
Synthesis and Adsorption Properties of Crosslinked Starch Microspheres (CSM)
Authors: Li Cong Jian , Lin Qin Tie , Liu Qian Jun , Pan Han Ping , Zheng Ru Ting
Published: December 2011

Starch as the material, MBAA as the cross-linking agent, Tween60 and Span60 as the emulsifier, K2S2O8-Na2SO4 as the initiator, the cyclohexane as the oil phase and the removal rate of methyl violet as an index, crosslinked starch microspheres (CSM) was synthetized by means of reverse suspension emulsion and graft-copolymerization method through orthogonal test and single factor optimization experiment. The results showed the optimal conditions of the preparation of the crosslinked starch microspheres(CSM) were as follow: the concentration of the starch is 5%, the dosage of the MBAA, initiator and emulsifier are 0.125g, 0.5g and 0.6g, the volume ratios between the Span60 and Tween60 is 85:15, and the volume ratio between the cyclohexane and water is 4:1.
Enhanced Optical Absorption in Modified One-Dimensional Metallic Photonic Bandgap Structures
Authors: Zhang Chun Mei , Meng Tao , Hao Yan Ping , Liu Fu Ping
Published: December 2011

We show theoretically that the optical absorption of one-dimensional metallic photonic bandgap (MPBG) materials, which consist of alternating Ag and MgF2 layers, can be substantially enhanced by modifying the structure properly through decreasing the thickness of top MgF2 layer to half and increasing the thickness of bottom Ag layer to fivefold. Using transfer matrix method, absorption spectra and the electric field distribution profiles are numerically calculated. The absorption spectrum under reverse-direction incidence is also investigated. Based on strong and direction-dependent absorption properties, the proposed MPBG structure could allow many potential applications such as unique photothermal absorbing materials.
Application of the Soil Nailing Wall on Foundation Engineering
Authors: Xu Zhong Qing , Ding Yong Gang , Yao Luo , Li Qiang Jun
Published: December 2011

The soil nailing wall is a kind of technology for supporting and strengthening the in-situ soil. The nails are integrated with the soil around tightly, so that they can form into a type of composite soil, relying on the frictional force of contact surface. Based on the analysis of the constructional scheme of the national stadium, the key factors for controlling the quality of the construction were found. The quality system during the project should be managed strictly. And the diameter, length and strength of the anchorage ought to be executed exactly. This scheme provided reasons for the national stadium’s soil nailing wall’s safety and quality assurance.
Fast Electroless Ni-P Coating on AM60 Magnesium Alloy at Low Bath Temperature
Authors: Mao Guo Bing
Published: December 2011

The Ni-P coatings were deposited on AM60 magnesium alloy by electroless plating process without or with accelerators. Without accelerators, the deposition rate is slow and required high bath temperature to obtain compact coating. There have many defects on the surface of the Ni-P coatings which deposited at high bath temperature. The composite accelerators were introduced into the bath for improving the growth rate and the quality of the Ni-P coating. Uniform, with no pores or cracks, “cauliflower-like” structure and complete Ni-P coatings were deposited only taken 20 min with additives at low bath temperature. The XRD result indicates that the structure of the Ni-P coating is amorphous nickel. The corrosion test results indicated that the corrosion resistance of this coated AM60 magnesium alloys increases distinctly as compared to bare alloys.
Diagnosis of White Spot Defects Drived from Gear Wheel Carbonization and its Corresponding Measures
Authors: Liu Hong Li , Liu Ming Xi
Published: December 2011

To account for the adverse effects of white spot defects onto the performance of gear wheel, physicochemical properties are studied based on the conducted surface carbonization experiment. Further, the geneses for white spot defects are discussed and the solutions to this problem are also clarified. It is found from the physicochemical analysis that the white spot defects occurred on gear surface can be classified into two parts: a) the ‘single white spot’, which originates from the sick point produced during the carbonization process, and b) the ‘multiple continuous spots’, which are produced by either the non-uniformity surface carbonization or the grinding burn or otherwise the micro ecarbonization caused by overheat on gear surface. For different white spot defects, different strategies should be employed: ultrasonic cleaning technique should be performed for the single white spot case, while for the ‘multiple white spot’ case, not only should the vacuum carburizing technique be employed to avoid surface non-uniformity of carbonization, but also vacuum oil quenching are needed to clear up the defects induced by micro decarbonization.
Surface Morphology and Infrared Absorption of Silicon Irradiated by Picosecond Laser Pulses in SF6
Authors: Liu De Wei , Huang Yong Guang , Zhu Xiao Ning , Wang Xi Yuan , Yu Hai Juan , Lin Xue Chun , Chen Ming Hua , Zhu Hong Liang
Published: December 2011

The microstructured samples were prepared by irradiating silicon surface with picosecond laser pulses in SF6. The surface morphology of microstructured samples irradiated at different laser fluence was characterized by SEM. The samples exhibited high optical absorptance over a wide wavelength range between 300 and 2700 nm. The absorptance of samples irradiated with the fluence of 1.0 J/cm2 was measured to be up to 95% between 1100 and 2700 nm. The infared absorptance of the surface-structured samples increased with increasing fluence. Whereas, as the annealing temperature was increased, the infared absorptance of the samples irradiated at the same fluence decreased. A tentative explanation for the effects of laser fluence and annealing temperature on the infared absorptance has been proposed based on the formation of mid-band gap impurity bands and the multiple reflections of light between microstructures.
Self-Protection of Flux-Cored Wire Surfacing is Applied to the Enhancement of Chute Lining Board
Authors: Zheng Li Juan , Liu Hui Ying , Fu Yu Ming
Published: December 2011

Self-protection of flux-cored wire surfacing is a new way to improve mechanical parts surface properties, and can improve mechanical equipment in the harsh condition of wear-resisting, corrosion resistant, high temperature resistant and oxidation resistance abilities. This paper based on this technology, research on its reinforcement in the roof without bells chute board, first analyzes the board of chute working conditions, stress and aggrandizement requirements, and using ANSYS simulated the displacement field and the equivalent stress field during the impact process, to explain failure modes, Then from the view of experiment to research the effect of molybdenum and niobium self-protection of flux-core wire, the hard facing layer microstructure analysis show that hard facing layer can obviously increase the matrix micro hardness and impact toughness, The microstructure of Niobium surfacing layer is more delicate than molybdenum surfacing layer, impact toughness is higher and more suitable for strengthening chute lining board.
Mechanical Properties of ADC12-6061 Aluminium Alloy Joints Produced by Friction Stir Welding
Authors: Li Jia Feng , Chen Xiao Gang , Xu Yong Gang
Published: December 2011

The aim of present work is to investigate the mechanical and microstructural properties of dissimilar ADC12 and 6061 aluminium alloy joints produced by friction stir welding (FSW). The microstructure of joints has been observed by employing optical microscope. Furthermore, the welded joints have been tested under tension at room temperature in order to analyse their mechanical properties. At last, the scanning electron microscope (SEM) was employed to observe the specimens’ fracture morphology.
An Improved Tool Path Model Including Gyroscopic Effect for Instantaneous Cutting Force Prediction in High-Speed Milling
Authors: Song Qing Hua , Ai Xing
Published: December 2011

The efficiency of the high-speed milling process is often limited by the occurrence of chatter. In order to predict the occurrence of chatter, accurate models are necessary. With the speed increasing, gyroscopic effect plays an important pole on the system behavior, including dynamic characteristic and rotating behavior. Considering the influence of gyroscopic effect on rotating behavior, an updated model for the milling process is presented which features as model of the equivalent profile of tool. In combination with this model, a nonlinear instantaneous cutting force model is proposed. The use of this updated equivalent profile of tool results in significant differences in the static uncut thickness compared to the traditional model.
Non-Abrasive Cryogenic Polishing Device on Cylindrical Surface Based on Recurdyn Dynamic Simulation
Authors: Liang Tian Zhu , Qu Shou Ping
Published: December 2011

With the increasing rotational speed of the aero-engine shaft and ultra-precision machine tool spindles, there has been the machine tool spindle with ten thousand Rpm. It demands that the spindles should have high rotational accuracy and ultra-smooth surface. In this paper, it takes use of the new ice tool polishing technology to polish metal cylindrical surfaces. The 3D model has been designed. And also the model has been analyzed by Recurdyn software. It verified that the experiment is feasible and effective.
Self-Assembly of Large Scale and High-Quality Colloidal Particle Films by Spin-Coating
Authors: Yang Zhao Ting , Xu Qing , Li Chao Rong
Published: December 2011

Colloidal crystal has attracted much attention both in fundamental crystal growth science and optical applications. This paper reports a simple and efficiency spin-coating method to fabricate high ordered colloidal crystals which have specific structures. We used the cleaned glass slide as substrates, the well dispersity 300nm (±1.2%) polystyrene (PS) spheres aqueous suspension (6.6 wt%) to assemble, and obtained highly organized colloidal crystal thin film by controlling spin-coating condition. Mostly, we got the large area plane hexagonal structure at the first layer and tetragonal construction at the second layer. The mechanism for this stacking way was studied. The obtained thin films were demonstrated by Field emission scanning electron microscope (FESEM) and Fast Fourier transform (FFT).
Effect of Slit Structure of Purging Plug on Stress Field
Authors: Huang Xiao Xiao , Xue Wen Dong , Liu Jie , Han Fa
Published: December 2011

The three-dimensional model of purging plug was analyzed by the finite element method. The influence of slit structure (length, width, center radius and numbers) on the maximum principal stress was Contrastive studied in argon blowing process under the same boundary conditions.
Investigation and Evaluation of the Safety Properties of Hardwood Athletic Floor System in China
Authors: Zhang Yu Ping , Peng Li Min , Fu Feng , Lv Bin
Published: December 2011

Field testing of safety characteristic was conducted on fifteen hardwood athletic floor systems with different constructions according to the procedures defined in Chinese standard GB/T 20239-2006 and EN 14904:2006. Device called Mastrad Skid Tester S885 was used to measure the coefficient of sliding friction (COF) of the fifteen floors and devices called Artificial Athlete Berlin was used to test shock absorption (SA) and vertical deformation (VD) of those floors. The COF of the fifteen hardwood athletic floors is between 0.4 and 0.5. About 80 percent of average of VA was between 1.0 mm and 2.0 mm. About 50 percent of the mean of VD was between 35% and 50%. About 50 percent of that was between 50% and 60%. It is vital to add the requirement of uniformity of the safety properties of hardwood athletic floor systems in Chinese standard. The deviation of the friction and VD can effectively be used to discriminate the uniformity of a floor.
Study on Surface Roughness Transformation during Metal Rolling
Authors: Almotairy Saud , Wei Dong Bin , Jiang Zheng Yi
Published: December 2011

Increasing the demand for cold rolled ultra thin strip as feedstock for miniaturized products has encouraged researchers to investigate the ways to increase the quality of such products, especially those related to strip surface roughness. Surface is known as quality factor in most of manufacturing processes. In this paper, the effect of the rolling parameters on the surface roughness transformation during metal rolling has been studied. The experimental results demonstrate that the surface roughness transformation during metal rolling is highly affected by the designation of the processing parameters such as finishing temperature, reduction, rolling passes and lubrication. The results have been discussed to verify the validity of the new findings.
Study on Oil-Ash Corrosion and Coal-Ash Corrosion Occurred in the Flue-Gas Side of Fossil Power Plant
Authors: Zhou Yong Yan , Zhou Yu , Lu Guo Hua , Chen Tian Sheng
Published: December 2011

A large number of high-speed soot particles would be produced after fossil fuels' (oil or coal) combustion in the boiler. These high-speed particles not only directly attack the heating surface of boiler tubes (damaging the tubes mechanically), but also condensate on the wall, causing even more serious chemical corrosion. The discussion has deeply studied the occurrence sites, reaction mechanism, influence factors as well as identification and prevention methods of oil-ash corrosion, coal-ash corrosion, so it would have a positive guiding significance for reducing (or preventing) the flue-gas side corrosion.
Comparison of Lu3Al5O12:Ce and LaBr3:Ce Scintillators in Gamma-Ray Spectrometry
Authors: CHEWPRADITKUL WEERAPONG , Wanarak Chalerm , Moszynski Marek , Swiderski Lukasz
Published: December 2011

The performances of Ce-doped Lu3Al5O12 (LuAG:Ce) and LaBr3 (LaBr3:Ce) scintillators were compared for γ-ray detection using photomultiplier tube ( XP5500B PMT) readout. For 662 keV γ-rays (137Cs source), an energy resolution of 3.5% obtained for LaBr3:Ce is much better than that of 6.7% obtained for LuAG:Ce, while the estimated photofraction of 28.0% for LuAG:Ce is higher than that of 16.2% for LaBr3:Ce. The light yield non-proportionality and energy resolution versus γ-ray energy were measured and the intrinsic resolution of the crystals was calculated. The coincidence timing resolution, obtained in this work for 511 keV annihilation quanta, was 583 ps and 204 ps, respectively, for LuAG:Ce –BaF2 and LaBr3:Ce – BaF2 detectors.