bluuebunny/crossref_metadata_2025 huggingface dataset:
Effect of EDTA on the Morphology and Size of SrCO3 Particles during Crystallization
Authors: Zhao Yan Hong , Jia Qing Yue , Gao You , Wang Xiao Jing
Published: November 2010

Strontium carbonate particles with different morphologies and sizes were synthesized successfully by a precipitation method in the presence of ethylenediaminetetra-acetic acid disodium (abbreviate as EDTA) at 25 . The phase structure and morphology of these SrCO3 particles were studied by X-ray diffraction (XRD) and scanning electron microscopy (SEM), respectively. The XRD results showed that orthorhombic crystalline SrCO3 particles were prepared in the absence of and presence of EDTA. It was found that this additive played an important role in controlling the morphology and size of the particles, which changed from dendritic to spherical shape as EDTA was added.
The Effect of Temperature Fluctuation on the Formation of Billet Surface Defect in the Initial Solidification Area
Authors: Jin Xiao Li , Lei Zuo Sheng , Deng Kang , Ren Zhong Ming
Published: November 2010

The heat transfer in steel continuous casting process under mold oscillation was calculated, and temperature fluctuation phenomena was found in the initial solidification area, the maximum value was approximate 16 °C. The effect of different continuous casting parameters on temperature fluctuation were analyzed, and the temperature fluctuation was considered to be a key factor to the formation of oscillation marks. The Index of Temperature Fluctuation(ITF) was proposed to predict the effect of temperature fluctuation on the formation of billet surface defects.
Finite Element Analysis on Stress and Strain of Embedded Fiber Bragg Grating
Authors: Xie Jian Feng
Published: November 2010

After FBG was protected and embedded into cement mortar, the stresses and strains on the FBG ,protected layer and cement mortar under varied temperature were analyzed in theory. In order to verify the theoretical analysis of stress and strain,a finite element analysis software(ANSYS)was used to simulate the stresses and strains on the FBG ,protected layer and cement mortar. The results of theoretical analysis matches the ones form simulations well.
Research on Fitting Curve's Characteristics of Turbulence Motion Locus Based on Image Projection Transformation and Light Stream Vector
Authors: Liang Zhong Wei , Liu Xiao Chu , Wang Yi Jun , Yu Zai Hai
Published: November 2010

The variation discipline of turbulence motion locus during the process of bearing’s strengthening grinding is a difficult point in the research fields of fluid theory. For the purpose of obtaining accurate discipline of turbulence motion, the fitting curve’s characteristics of turbulence motion locus based on image projection transformation and light stream vector is investigated. Through tracing particles be equally-distributed scattered into flow field, they reflect turbulence’s motion discipline accurately. After each particle’s movement has been shot from different orientations in continuous time-points, thus sequential conjugate images have been obtained. Relationship of image projecting transformation is established for determining these particles’ absolute three-dimensional coordinates. Combining with light stream vector, these particles’ motion vectors in each instantaneous moment can be deducted and mathematical models of motion locus can be gotten. Then correlative mathematical characteristics are built, their variation tendency is analyzed in different flow velocities. This experiment provides theoretical foundation and technical preparation for research of complicated turbulence and selection of fluid signal sampling’s condition.
A Numerical Simulation of the Electromagnetic Hot-Top Casting of 6063 Aluminum Alloy
Authors: Wang Xiang Jie , Cui Jian Zhong , Zhang Hai Tao
Published: November 2010

On the basis of conventional hot-top casting and Casting, Refining and Electromagnetic process, a lower frequency electromagnetic field was applied during the hot-top casting process. A comprehensive two-dimensional (2-D) mathematical model based upon the ANSYS and FLUENT has been developed for the computation of the electromagnetic field, solidification, fluid flow and heat transport during conventional and low frequency electromagnetic hot-top casting processes. The results show that there is a good agreement between the experimental results and calculated results.
An Experimental Study on the Characteristics of Chemically Synthesized Nano-Cement for Carbon Dioxide Reduction
Authors: Jo Byung Wan , Choi Ji Sun , Kang Seok Won
Published: November 2010

Cement is becoming a principal factor in air pollution because of the creation of CO2 during its manufacturing. The exhaustion of the natural resources needed for Portland cement production is also an issue. Therefore, a substitute material for this type of cement is needed. Nano-scale materials are of great interest due to their unique optical, electrical, and magnetic properties. These properties are strongly dependent on the sizes and shapes of the particles, and, therefore, it is important to be able to develop the construction part which retains the excellent properties of the nano-sized material. The purpose of this study was to synthesize nano-powder as a substitute for cement using a chemical method. This study investigated the compressive strengths of concretes with various compositions. Specimens were tested for compressive strength three, seven, 14, and 28 days after manufacture. In the results of this study, the medium-sized (50% by weight) nano-cement particles created via chemical synthesis were less than 168 nm in size, and the compressive strength of the mortar prepared using these nanoparticles was 53.9 MPa
CC Path Generation Method in 5-Axis Surface Machining with a Flat-End Cutter
Authors: Chen Liang Ji , Feng Xian Zhang
Published: November 2010

A 5-axis machining method of Non-Uniform Rational B-Spline (NURBS) surface has been proposed in this paper. With the local curvature and the machining error, the step-size was calculated to get the parameter of the next Cutter-Contacting (CC) point. With the method of coordinate transformation, effective machining radius of a flat-end cutter had been deduced and the step-over formed by two adjacent CC paths were implemented. The parameter increment along the CC path interval direction was calculated by using geometric analysis of the local area of CC point. Finally, once all of CC points on the NURBS surface had been obtained, the CC paths for 5-axis surface milling were generated.
Research on Performance of New Pressing Binder in Hardmetal
Authors: Meng Xiao Wei
Published: November 2010

The advantages and disadvantages between the pressing binder of hardmetal in existence are analyzed. A new type of binder named QSD is introduced and a series of properties are studied. The experiments show that QSD has been tested to dissolve in alcohol. The materials of hardmetal are milled in alcohol mixed with QSD, achieving a molecule dispersing slurry. The slurry adapts to spray drying with low viscidity. The mixture of the hardmetal prepared by QSD is fine, and soft with good flowability. They are capable of pressing complex form of products that couldn’t be formed with PEG, paraffin wax binder by comparing the experiments. The compacting force has reduced 20% compared to PEG.. The pressing products are effectively less vices of delamination and crack due to the low brittleness and high weight of compact. The products made by QSD fit continuous sintering and there are few remainder carbon in the sintered products. Microstructural observation reveals that the Co particle distributes homogeneously in the WC particle with the pressing binder QSD. So QSD is one kind of considerably ideal cemented carbide binder that combines the advantages of PEG, SBS.
The Effect of Helix on the Nonlinear Analysis of Threaded Connection
Authors: Sun Yu Juan , Liao Ri Dong
Published: November 2010

Based on the axisymmetric and 3-D finite element models, the axial-load and stress distributions on each thread of the threaded connection have been studied. The effect of helix and the elastic-plastic behavior of the material at the thread roots have been explored. Simulation results indicate that the axial-load and stress distributions obtained from the axisymmetric finite element model show good agreement with the results of 3-D analysis in both elastic and plastic states with the same mesh density. So the axisymmetric model can be used to study the axial-load and the stress distributions of the threaded connection subjected to axial-load. The axial-load and stress distributions in threads are very sensitive to the applied load. With increasing the applied forces, the axial-load and stress distributions over teeth become homogeneous eventually.
Pb Finite Element Analysis for Profile Wear of Rolling Radial Tire with Camber Angle
Authors: Cheng Gang , Wang Wei Dong
Published: November 2010

A three-dimensiona1 nonlinear finite element analysis(FEA) mode1 of radial tire，which includes the materia1 nonlinearity and the geometric nonlinearity of the 1arge deformation, is established to analyze the effective factors on the wear resistance of 195/60R14 tire．It shows that the distribution of the friction force in the ground-contact area gradually changs from greater inside and smaller outside to greater outside and smaller inside with the increase of the 1oad of tire. It also shows that the maximum friction force, which decreases at first and increases later as the angle of belt cord increases, occurs in the shoulder area. The static friction force in ground-contact area is symmetrically distributed. On the one hand, the over inflation pressure leads to the increase of the maximum friction force resulting in the premature wear in the middle of crown under the same load. On the other hand, the under inflation pressure leads to the phenomena of bridge effect, which is resulted in the uneven wear in the tread．
Effect of Ambient Temperature on Wear of Cemented Carbide Tool Material
Authors: Zhang Hui , Deng Jian Xin , Li Gui Yu , Ai Xing , Zhao Jun
Published: November 2010

Cemented carbide has relatively good mechanical properties, so it is widely used as cutting tools. In this paper, a sliding wear test at high ambient temperature between cemented carbide tool material and ceramic was carried out using a ball-on-disc wear-test machine. The characteristics as to wear rate and friction coefficient were investigated. The special wear rate increased with an increase in operating temperature. The cemented carbide material with addition of TiC phase gave better wear resistance than cemented tungsten carbides at elevated temperature. SEM technology was adopted to observe the worn surfaces of specimens and wear mechanism were simultaneously discussed.
Effect of MAP on Quality of Rice for Super-Long-Term
Authors: Li Xi Hong , Wang Jing , Ge Ling Yan , Wan Sen
Published: November 2010

In this study, effects of Modified Atmosphere (MA) packaging on the quality of rice after a long term storage at room temperature have been investigated. PVC films with different thicknesses and woven bag were used as the package materials for rice samples. Results showed that MA packaging had a significant effect on the quality of the rice. After an extended period of storage, the rice in woven bag showed most severe quality deterioration compared to those stored in PVC packages. Rice packed in 0.05 mm PVC film package has the lowest value of total acid among all samples. The increase of fatty acid content in rice packed in 0.03 mm film, 0.05 mm film, 0.08 mm film and 0.12 mm film was 38.58 mg KOH/100g, 18.96 mg KOH/100g, 26.83 mg KOH/100g and 32.64 mg KOH/100g, respectively. The volatile aldehyde components accumulated in the stored rice are mainly acetaldehyde, valeraldehyde and hexanal. Small package with a MA has obvious benefits in regulating the metabolism and accumulation of volatile aldehyde components in the rice. Rice samples stored in a package of 0.05mm film had the lowest value of volatile aldehyde, while those in 0.03mm film had the highest value. This study suggests that MA packaging with a PVC film of 0.05 mm shows the best effects in maintaining the quality of rice after an extended period of storage (3 to 5 years).
Effect of Heat Input on Microstructure and Properties in Heat Affected Zone of ASTM A572 GR.65 Steel
Authors: Zhou Ji Lie , Yang Jing Hua , Ye Yin , Dai Gang Ping , Peng Xin Yuan
Published: November 2010

The correlation among heat input (HI), microstructure and properties in heat affected zone of ASTM A572 GR.65 steel (GR.65 steel) was investigated using optical microscopy (OM), Vickers hardness tester and Charpy-V-Notch (CVN) testing. The result shows that due to the restriction by the Nb(CN) precipitates, the grain size in coarse grain heat affected zone (CGHAZ) at a heat input of 10 kJ/cm is 75 µm, which is half as that at the heat input of 40 kJ/cm. It is indicated that weld preheating is beneficial to the toughness in CGHAZ at low heat input of 10 kJ/cm, while it appears the opposite effect at high heat input of 40 kJ/cm. The heat input has a great influence on dissolution of precipitated particles and the austenite grain size, which contributes a lot to the microstructure and properties of GR.65 steel.
The Analysis of Scenario Characteristics in Life Cycle Assessment
Authors: Wang Xiao Wei , Li Jian Feng , Li Jian Zhi , Li Fang Yi
Published: November 2010

Aimed at few reflections on the scenario characteristics in the most methods of LCA, this paper presents a new approach taking specific information of scenario into account in the environmental impact of product. By analyzing the relation between scenario and environmental impact, the attributes of space, time and person are extracted as the most basic characteristics. In order to avoid the deficient of science modeling between the scenario attributes and the environmental impact processes and to use conveniently, the concept of scenario characteristic coefficient is proposed and the three types of coefficients are expressed in detail applying the existing data or statistic. The method of LCIA considering scenario characteristics is presented by integrating the characteristic coefficients into the LCI processes. And this method is applied to study the scenario characteristics of an LCA of electromotor.
Titanium Positive Plate Manufacturing Process and Denitrification Mechanism
Authors: Zhang Li Ping , Ke Lei , Xie Miao Miao , Guo Yuan Jie , Hu Qian Yu , He Xu Wen
Published: November 2010

Prepared a electrode with high concentration and strong active oxidizing property which used titanium as anode’s substrate material, used gradient method the anode surface was coated with a definite ratio RuO2、TiO2、IrO2、SnO2、Ga and Ce in order to extend the operational life span. Use scanning electron microscope to present the surface property, the result shows that the surface coat of self-made titanium positive plate is densification and well-distributed which has good catalytic activity and reaction stability, meanwhile the surface coated with metallic oxides has less and short cracks which can extend the useful life. Through the electrochemistry property detection by electrochemistry workstation, Tafel curve shows that the chlorine precipitation potential is 1.41V which is just a little higher than the standard potential 1.36v of Cl- reacting to form Cl2, meanwhile lower than the oxygen precipitation potential, these shows that the plate has good electro-catalysis property and selectivity. The self-made experimental setup includes four parts as direct supply, reactive tank, electrode, collecting bottle. Prepared solution with deionized water and analytical pure agents with NH4Cl and NaCl, with draining water method collecting the electro-catalysis gas and gas chromatographic analysis shows the main component includes N2 62.73%, O2 21.47%，H2 13.95%，Cl2 1.85%, meanwhile analysis the trends of nitrogen forms concentration, chloridion concentration and pH by electrolysis time, concluding that the indirect oxidation is dominant process during electrochemistry, active substrate OCl- is the principal oxidation. The electrolyte pH keeps range between 7.5 and 9.5 which is favorable to free ammonia forming that can be directly electrochemical oxidized, meanwhile is disadvantage of free chlorine forming that can keep cyclic utilization in solution.
Preparations and Properties of Amorphous/Nanocrystalline Ni-Mo Alloy Coating Obtained by Electrodeposition
Authors: Li Ning , Chen Wei Zeng , Jing Bao De , Xu Hong
Published: November 2010

The amorphous/nanocrystalline Ni-Mo alloys were deposited in alkaline nickel carbonate solution in this paper. It is found that the molybdenum content in the deposit obtained in carbonate solution is to 21.76 at.% with amorphous and nanocrystalline phase structure. Under the same conditions, the amorphous/nanocrystalline alloys are more accessible to be obtained in carbonate solution as the sulfate solution. And the deposits with a tiny internal stress and tiny granules and well-proportioned grains at the substrate were relatively better and easy to be controlled with a better mechanical performance.
The Synthesis and Properties of a Novel Solid Polyphosphazene Electrolyte for Lithium Ion Battery
Authors: Yang Ming Shan , Liu Jian Wei , Yu Jin , Zhang Xu , Wei Jing , Li Lin Kai
Published: November 2010

Polydichlorophosphazene was synthesized from hexachlorocyclotriphosphazene by high-temperature ring-opening polymerization, and poly(2-(2-methoxyethoxy) ethanol phosphazene)(MEEP) was synthesized by reacting polydichlorophosphazene with alcohol sodium. The optimal synthesis parameters were obtained and the structure of MEEP was analyzed by NMR. Then polyphosphazene electrolyte was prepared by mixing MEEP with LiCF3SO3. The results indicated that the electrolyte prepared in this paper has high decomposition temperature, and its room-temperature conductivity is up to 1.187×10-4 S/cm.
Designing on Magnetic Seal Ash-Unloader without Abrasion
Authors: Qi Li Qiang , Yuan Yong Tao
Published: November 2010

The rigid seals currently being used for the ash unloading device with the impeller under the hopper of the electrostatic precipitator are easy targets of wear and tear. In addition, the airproof capability of these seals is not perfect. In this light, an advanced powder magnetic seal design which installs permanent magnets at the top of the vane and utilizes the magnetism of Fe3O4 in fly ash to seal the space between two vanes is discussed in this paper. In the self-designed device, three categories of permanent magnet parameters and four kinds of powders with respective with respective magnetic powder mass fractions of 7%, 9%, 12%, and 15% were chosen. The airproof capability was also measured. The results show that this device has excellent airproof capability, can withstand wear and tear, and has a low replacement frequency.
Whole Field Structural Health Monitoring by Polymer-Matrix Carbon Fiber Smart Layer
Authors: Zheng Hua Sheng , Zhu Si Rong , Li Zhuo Qiu , Ye Lian
Published: November 2010

With epoxy reinforced by short carbon fiber mats, a skin-like strain sensor, polymer-matrix smart layer was developed, which can continuously cover the structural surface to sense strain for the whole filed. The smart layer was proved to be an effective strain sensor for tensile strain up to 0.8% by a monotonic tension experiment, exceeding this limit cause nonlinearity in the resistance response. The damage sensitivity of the smart layer was revealed by the monitoring for a FRP beam with prefabricated defect. Based on its sensitivities, the smart layers was applied in the health monitoring for a concrete beam under three-point bending, the result showed a good correlation between the resistance change of the smart layer and the load applied on the structure. The emergency of structure damage can be monitored by the turning point on the resistance-deflection curve of the smart layer.
Effects of Processing Parameters on the Temperature Field of Melts in Aluminothermic Reaction to Prepare Bulk Nanocrystalline Fe3Al
Authors: La Pei Qing , Lv Rui Jiao , Guo Xin , Zhang Dan
Published: November 2010

Making use of the finite element analysis software ANSYS, we calculated the effects of different processing parameters on temperature, cooling rate and superheating time of Fe3Al melt in aluminothermic reaction to prepare bulk Nanocrystalline Fe3Al. The results showed that, with the increase of substrate thickness and reduction of reactant’s quantity, cooling rate of the Fe3Al melt at the initial cooling stage became larger, while the melt purification became worse. With the increase of argon pressure, the Fe3Al melt cooled a little quicker. The cooling rate of melt cooled by glass substrate was lower than that of the melt cooled by 1045 steel and Cu substrate, while the melt purification became better. With the increase of Al2O3, Fe3Al diluents content, the cooling rate at the initial cooling stage became lower, and the melt purification became worse. The experiment verified that the calculated results were in good coincident with the experimental results.
Mechanochemisitry Synthesis of Al-Rich Layered Double Hydroxides
Authors: Yu Hong Bo , Wang Jing , Gao Hong
Published: November 2010

In present work mechanochemical synthesis of fine dispersed MgAl-CO3 LDHs is based on the preliminary mechanical activation of mixture of magnesium hydroxide, aluminium hydroxide and sodium hydrogen carbonate in a planetary activator AGO-2, followed by the thermal treatment of activation products at a temperature of 90 . The Mg/Al molar ratio was discussed. The samples were characterized by x-ray diffraction, thermogravimetry, scanning electron microscope, and energy dispersive spectrometer. According to obtained data the interaction mechanism was proposed.
Simulation Analysis of Emergency Evacuation on Large Passenger Rail Terminal
Authors: Liang Ying Hui , Zhang Xi , Zheng Pan
Published: November 2010

Emergency evacuation of large passenger station passenger terminal operations management is an important part of management. In this paper, it use legion simulation software, on the Beijing South Railway Station passenger emergency evacuation simulation test, first introduced the Legion simulation software and simulation process, followed by the design of the total number of 5000 and 10,000 people in different device configurations evacuation simulation program; re-use simulation software legion For each program the simulation analysis, the number of the simulation program evacuation and evacuation density optimization Finally, emergency evacuation measures and proposals for the reasonable development of passenger flow planning and organization of decision support programs.
Simulation and Experiment Based on the Mixed Robust Optimal and H∞ Controller of PMLSM
Authors: Wu Guo Qing , Zhang Yu Mei , Zhu Wei Nan , Zhou Jing Ling
Published: November 2010

There are many uncertain sensitive issues such as parameter disturbance and edge effect when PMLSM running. In order to solve these problems, a method called mixed robust optimal and H controller is presented. Robust optimal and H∞ control strategy is made use to design the mixed robust optimal and H controller of PMLSM. Large external disturbance and internal nonlinear perturbations can well be eliminated by this controller, and it’s easy to be practiced. MATLAB/SIMULINK is made use to simulate the system. With the help of PMAC board and COPLY controller permanent brushless motor controller, hardware test platform is built. The test results show that mixed robust optimal and H controller has strong robustness and traceability compared with traditional PID control method.
Crack Resistance of Connections of Cross Shaped Steel Encased Ultra High-Strength Concrete Column to RC Beam under Cycle Loads
Authors: Yan Chang Wang , Jia Jin Qing , Zhang Ju
Published: November 2010

In order to investigate the crack resistance capacity of cross shaped steel encased ultra high-strength concrete (CSSEUHSC) column to reinforced concrete (RC) beam connection subjected to reversal cycle load, six interior joint specimens were tested with various axial load ratio nt and volumetric stirrup ratio ρv. A discussion on the crack resistance capacity was presented. Calculation methods of crack resistance capacity were deduced and calculating results were in good agreement with the experimental results. The research results indicated that parameters of CSSEUHSC column to RC beam connection with better crack resistance performance may be referred for engineering application.
Effect of Substrate Temperature on the Haze and Properties of SnO2: F Thin Film Coated on Glass (FTO) by Spray Pyrolysis Process
Authors: Zhao Qing Nan , Wu Shuo , Miao Deng Kui
Published: November 2010

The textured thin films of fluorine-doped tin oxide (FTO) were prepared onto preheated glass substrates by a spray pyrolysis technique, using dehydrate stannous chloride (SnCl2:2H2O) and ammonium fluoride (NH4F) mixed with alcohol, as precursor. The haze and properties of the films heat treated at different temperatures from 400 to 550 were characterized by X-ray diffraction (XRD), 3D Digitale Mikroskop, Atomic Force Microscopy, UV-Vis spectrometer, sphere photometer and four-probe instrument. The results show that, with the increase of the substrate temperature, XRD peaks become sharper, the grain sizes grow up rapidly, and the crystal structure is improved gradually; the surface topography become like the islands and the haze achieves 16.47%. The lowest sheet resistance of the films is 9.7Ω/□. The effect of the substrate temperature on the haze, electric property and optical transmittance of the FTO films has been discussed in detail. The results show textured SnO2:F thin film deposited onto preheated glass substrates by a spray pyrolysis technique would be used as transparent electrode in amorphous silicon(a-Si) solar cells due to its excellent properties.
Design and Choose Durability Assessment Parameter of Concrete in Salt Soil Region
Authors: Qiao Hong Xia , Yu Hong Fa , He Zhong Mao
Published: November 2010

After the assessment targets on concrete durability were optimum designed rationally to be assessment parameters, the durability deterioration course of concrete in sulfate environment was characterized using designed assessment parameters. The results show that, every performance deterioration degree of concrete can be compared on the same coordination axis by assessment parameters. The assessment parameters were applicable the same determination criterion, and the determination principle is simple and convenient. The comparing the deterioration course and sensitivity degree of concrete performance is much easy. If concrete performance of anti-sulfate erosion was experimented at laboratory, the result assessment ought to use the two non-destructive test assessment parameters.
Preparation and Properties of Silicon-Corundum-Silicon Nitride Composites
Authors: Wei Jun Cong , Tu Jun Bo
Published: November 2010

Effects of silicon powder additions on the phase composition and microstructure of silicon- corundum-silicon nitride composite refractories were investigated guided by the theory of metal transient plastic phase and the Si-O-N phase diagram. On this basis, silicon-corundum-silicon nitride composites were prepared under air atmosphere. The results showed that the addition of silicon powder could reduce the width of the oxidized film and improve the densification; silicon addition could decrease the oxygen partial pressure in the specimens and contribute to the sintering of the materials. Part of silicon could remain in the materials. The industrial experiments suggested that silicon powder mostly filled in the interstices of the matrix of the sintered products with addition of less than 8 wt.% Si powder, and with increasing Si powder additions the densification of the product was improved, cold strength increased, and hot strength also increased due to the in-situ formed fibrous SIALON by silicon powder; silicon powder formed continuous phase which led to the decrease in densification and hot strength when more than 8 wt.% silicon powder was added.
Experimental Study on Improving Abrasion Resistance of Sizing Crusher Tooth
Authors: Pan Yong Tai , Li Yong Zhi
Published: November 2010

The shorter service life of sizing crusher tooth is a difficult technology problem. At present the coal classification used in crushing machine, due to poor working conditions, despite the use of wear resistant surfacing electrode to improve the wear resistance of broken teeth, broken teeth, but not to the average life of six months, the subject of study was significantly improve the life of the crusher tooth. To improve the service life of sizing crusher tooth, some research has been done, through system analysis and test some result can be concluded.
Nanoparticle/Epoxy Nanocomposites: Impact, Flexural and Thermal Properties
Authors: Chen Lei , Xu Zhi Wei , Li Jia Lu , Chen Guang Wei
Published: November 2010

Nanocomposites based on epoxy which were reinforced by different nanoparticles were fabricated. Five types of nanoparticles (corresponding to multi-walled carbon nanotubes (MWNTs), nano-Al2O3, nano-TiO2 and nano-SiO2) were chosen and the weight content of the nanoparticles was 2wt.%. Impact, flexural and thermal-mechanical properties of the nanocomposites were investigated. Compared with neat epoxy, impact strength of systems which were reinforced by MWNTs and nano-TiO2 was increased by 60%. Concerned with the flexural properties, there was also an increase of about 10%~50% with the addition of the some nanoparticles such as MWNTs, nano-TiO2 and nano-SiO2. The heat resistance of the EP was not decreased by adding nanoparticles and the thermal properties of the systems were even improved with the addition of MWNTs.
Residual Deformation Behavior of Reinforced Rock-Fill Materials
Authors: Lin Yong Liang , Zhang Meng Xi , Li Xin Xing
Published: November 2010

Reinforcement technology is widely used in rock-fill dams in high seismic hazard zones. The evaluation of reinforcement on deformation and safety is concerned and it is one of the major study objectives in rock-fill engineering. The residual deformation behaviors of reinforced rock-fill materials were experimentally studies by use of a triaxial apparatus. The effects were analyzed of intervals of reinforcement layers, confining pressures and the conditions of cyclic loading on residual deformation. Results show that reinforcement improves the residual deformation behaviors of rock-fill materials. Both the residual shear strain and the residual volumetric strain are deduced. Based on the test results, the mechanism of the influence of reinforcement on residual deformation is proposed tentatively.
Chiral Resolution of Racemic (±)-1,1'Bi (2-Naphthol) by Use of Molecularly Imprinted Polymers
Authors: Dong Hong Xing , Tong Fei , Li Jun Qing , Wang Zhen Xing , Wang Yan Hui , Shen Xian De
Published: November 2010

Polymers imprinted with (S)-(-)-1,1’-bi (2-naphthol) and (R)-(+)-1,1’-bi (2-naphthol) have been prepared by non-covalent imprinting. A combinational procedure was used to optimize the functional monomer and crosslinker. A copolymer of 2-vinylpyridine and divinylbenzene resulted in the best chiral recognition. The ratio of template to functional monomer and solvent in the pre-polymerization mixture were also optimized. The imprinted polymers were used as stationary phases in high-performance liquid chromatography (HPLC). The molecularly imprinted polymers (MIPs) were more selective when prepared using a less polar solvent. Effective separations of the enantiomers of racemic (±)-1, 1’-Bi (2-naphthol) were achieved by use of acetonitrile as mobile phase; no cross-selectivity was observed. Interactions between functional monomers and template were investigated by 1H NMR spectroscopy. The results suggest that hydrogen-bonding between the functional monomer and the template and π-π stacking interaction between the cross-linker and the template may contribute to chiral recognition.
Study on Synthesis and Thermal Property of Polyvinylamine
Authors: Zhao Hong Chi , Li Qi , Xu Wen Yu , Huang Fan
Published: November 2010

Polyvinylamine (PVAm) and polyvinylamine chloride (PVAm•HCl) were synthesized by Hofmann degradation of polyacrylamide (PAM). The reaction condition is gentle and the operation is safe, simple and economical so that it is a good reaction method. The chemical structures and thermal properties of the polymers were studied by Fourier transform infrared spectrometer (FTIR), nuclear magnetic resonance spectrometer (NMR), X-ray diffractmeter (XRD) and thermogravimetric analyzer (TGA). Synthesis of PVAm•HCl was confirmed by the intensities of the characteristic peak of -CONH2 decreased and the appearance of a new absorption peak at 1530cm-1 (due to N-H bond of -NH3+ ) in the FTIR spectrum, the appearance of the characteristic absorption peaks of carbon atoms in the 13C NMR spectrum, the appearance of chemical shift assignments of proton in 1H NMR spectrum and the appearance of characteristic dispersing diffraction peak between 22.5° to 25.2° in the XRD spectrum, respectively. PAM had three decomposing stages, but PVAm•HCl had two decomposing stages. TG curve of PAM and PVAm•HCl showed that the initial decomposition temperature were 190oC and 140oC, respectively. The thermal stability of PVAm•HCl was poorer than that of PAM.
Theory and Experiment of Isotropic Electromagnetic Beam Bender Made of Dielectric Materials
Authors: Deng Qi Bo , Hu Jin , Chang Zheng , Zhou Xiao Ming , Hu Geng Kai
Published: November 2010

In this paper, we utilize the deformation transformation optics (DTO) method to design electromagnetic beam bender, which can change the direction of electromagnetic wave propagation as desire. According to DTO, the transformed material parameters can be expressed by deformation tensor of the spatial transformation. For a beam bender, since the three principal stretches at each point induced by the spatial transformation are independent to each other, there are many possibilities to simplify the transformed material parameters of the bender by adjusting the stretches independently. With the DTO method, we show that the reported reduced parameters of the bender obtained by equivalent dispersion relation can be derived as a special case. An isotropic bender is also proposed according to this method, and it is fabricated by stacking dielectric materials in layered form. Experiments validate the function of the designed isotropic bender for a TE wave; it is also shown that the isotropic bender has a broadband with low loss, compared with the metamaterial bender. The isotropic bender has much easier design and fabrication procedures than the metamaterial bender.
Photocatalytic Activities of Visible-Light-Driven TiO2 Films Codoped with Aluminum and Nitrogen
Authors: Cheng Xiao Ling , Hu She Jun , Hu Yong Jun , Yu Lin , Wei Zhi Gang
Published: November 2010

The titania films codoped by aluminum and nitrogen have been prepared by cathodic vacuum arc with titanium aluminum alloy target in an O2/N2 gas mixture. The films were characterized by X-ray diffraction (XRD), X-rayphotoelectron spectra (XPS) and ultraviolet-visible spectra (UV–vis). The results showed that all films annealled were crystalline anatase structure with a (101) preferential orientation, XPS revealed that Al and N were successfully doped into the lattice of TiO2. The optical properties of the films revealed that the spectrum response of the Al, N-codoped TiO2 films extended from the UV region to the visible region. The absorption of the Al, N-codoped TiO2 film in the visible region(>400 nm) was enhanced, compared with the pure TiO2 film and N-doped TiO2 film. The Al, N-codoped TiO2 film showed the best photocatalytic activities for the oxidative destruction of Acid Fuchsin (AF) under visible light irradiation.
Study on Inorganic Phase Change Materials Encapsulated by Rice Straws
Authors: Hou Gui Hua , Zhu Xiang
Published: November 2010

Na2SO4 solution was impregnated into rice straws, then the straws impregnated with Na2SO4 was cemented using water glass and molded to shaped phase change plate. The plate was subsequently inserted into the concrete bricks with rectangular holes, assembled as phase change bricks. The latent heat of phase change of the plate was measured by DSC, the microstructure of the plate was observed by SEM, and the heat insulating property of the brick was investigated. The results are as follows. The rice straws can encapsulate 2 times Na2SO4•10H2O in mass and the phase change heat of the plate is 121 J/g. The microstructure shows that the rice straws and hardened water glass play an encapsulating action for the package of Na2SO4•10H2O. The weight loss of the plate was 0.9% after 30 times of phase change cycles. For the concrete bricks (size: 240×240×115 mm) inserted with phase change plates, when the heated surface temperature was 80 oC and the initial cold surface temperature was 14.5 oC, the needed time that the cold surface temperature rose to 25 oC was 17 h, which was 6.5 h and 9 h longer than the concrete bricks inserted with rice straw plates and the original concrete bricks, respectively. When the heating was maintained for 5 h and 8 h, the cold surface temperature increased by only 1.4 oC and 3.9 oC and the temperature difference between the cold surface and hot surface was 64.1 oC and 61.6 oC. This study provides a new way for the encapsulation of phase change materials and its application in construction.
Solid Super Acid of S2O82-/FexOy-CuOx Catalytic H2O2 to Remove Organic Pollutants in Water
Authors: Zhang Ying Jie , Liu Guo Rui , Li Da Peng , Tian Yue Xiao , Zhang Li , Li Li , Ma Jun
Published: November 2010

Solid super acid(S2O82-/FexOy-CuOx)was prepared and used as a Fenton-like catalyst to decompose H2O2 for the removal of orgnanic pollutants in water. The catalytic activity of S2O82-/FexOy-CuOx was evaluated by the degradation of organic pollutants and the decomposition of H2O2. The results show that the catalytic activity of S2O82-/FexOy-CuOx to decompose H2O2 is higher than that of S2O82-/FexOy. The reason for this may be due to the dissolved of Fe2+ from the S2O82-/FexOy-CuOx, and the concentration of dissolved of Fe2+ is proportional to the concentration of organic pollutants in water. The degradation rate of phenol by the catalyst of S2O82-/FexOy-CuOx is obviously higher than that by the catalyst of Fe2+ ion under the same conditions. BET measurements show that the surface area of S2O82-/FexOy-CuOx is larger than that of S2O82-/FexOy.
Effect of Annealing Conditions on Microstructure Evolution of NiMnFeGa Shape Memory Thin Film
Authors: Wang Hai Bo , Ma Li , Cai Wei
Published: November 2010

The microstructure evolution of sputtered polycrystalline Ni54.75Mn13.25Fe7Ga25 ferromagnetic shape memory thin film annealed under different conditions is studied. Microstructure of different annealed films was studied using Transmission Electron Microscope (TEM) and corresponding selected area electron diffraction (SAED) patterns. The result shows that in the microstructure of as-deposited Ni54.75Mn13.25Fe7Ga25 free-standing film, after annealed at 1073 K for different time, the crystalline grain grows up with the increase of the annealing time. By analysis of the SAED patterns, the structure of the thin films change from face-centered cubic austenite to orthorhombic structure martensite compared between the film annealed at 1073 K for 10 mins, 1hr, 4 hrs, and 24 hrs respectively. It indicated that the heat treatment is an effective method of crystallizing behavior for the thin film.
Experimental Investigations of Shear Lag Effect in Orthotropic Composite Box Beam
Authors: Wu Ya Ping , Wang Yin Hui , Wang Li Xia , Bian Zu Guang
Published: November 2010

The influence of curing time on the mechanical property of the phosphoaluminate cement (PAC) was investigated, and the mechanism was discussed as well. The phase composition and morphology of hydration products, electrical properties, porosity and pore size distribution of PAC cured different age were analyzed with XRD, EIS and MIP. The results showed PAC has the property of early-high strength, and the compressive strength of PAC cured for 1 day was about 70% of 28 days’. The main hydration products of PAC are micro-crystal phase and gel of phosphate and phosphoaluminate which formed compacter microstructure. In addition, there are no calcium hydroxide (CH) and ettringite (AFt) produced during the process of hydration. The compressive strength of PAC increased with age, which was due to more products continuously produced. The ac resistance analysis manifested as the change of the nyquist pattern and resistance value.
Effect of Annealing Temperature on Properties of ZnO Thin Films
Authors: Zhang Dong Ping , Fan Ping , Zheng Zhuang Hao , Cai Xing Min , Mao Liang , Chen Tian Bao , Chi Jing Rong
Published: November 2010

ZnO thin films were deposited by DC reactive magnetron sputtering, and the samples were annealed from 100°C to 400°C, respectively. With the help of x-ray diffractmeter (XRD), spectrophotometer, and photoluminescence (PL) spectroscopy system, the microstructure, intrinsic stress, optical properties, and PL properties were investigated, respectively. The XRD results reveal that all the ZnO films are found to have the hexagonal wurtzite structure with prominent (002) peak. With the annealing temperature increasing, the grain size increased accordingly. All the samples exhibit compressive stress, and the stress value decreasing with annealing temperature increasing. Optical transmittance spectra investigated that all the samples have high transmittance in visible range. With annealing temperature increasing, peak transmittance rising of the sample were observed. The fundamental absorption edge, which associated with band gap of materials, shifting to longer wavelength is observed too. PL results shows that the sample annealed with 300°C have higher intensity emission peak.
Research on the Shielding Performance of Electromagnetic Shielding Clothes
Authors: Li Yan , Zhang Wen Bin
Published: November 2010

Electromagnetic shielding clothes for protecting human exposure from harmful radio waves have been commercialized. However, most research has so far focused on the fabrics. In this paper, based on the orthogonal experiment method, design the structure of the electromagnetic shielding clothes, and conduct the performance test. Through direct and variance analysis, find out the significance degree of the structure factors, and then get the best level combination of the factors, thus provide a theory basis for optimization structure design of electromagnetic shielding clothes.
Steady Thermal Stresses in a Ceramic/FGM/Metal Composite EFBC Plate under Convective Heat Transfer Boundary
Authors: Tu Dai Hui , Xu Yang Jian , Zhou Xiao Li
Published: November 2010

The steady thermal stress distributions and effect factors in a ceramic/FGM/metal composite EFBC plate considered constant material properties under convective heat transfer boundary were investigated by the FEM and the Sinpson method. From numerical calculation, when , T0=300K, Ta=400K and Tb=1 400K, the stress distributions in the plate were obtained. The results are as follows. With the increase of the FGM layer thickness, the stress distribution in the composite plate is more reasonable. Compared with M=0.2, when M=5, the compressive stress on the ceramic surface reduces by 10.2%, and the tensile stress on the metal surface reduces by 21.7%. With the increase of A, the variations of thermal stress curves become big. Compared with A=0, when A=3.99, the tensile stress on the metal surface increases by 198.0%, and the maximum compressive stress on the surface of ceramics increases by 66.0%. Compared with the mutation of thermal stress at the cohesive interface of ceramic / metal two-layered composite plate, the thermal stress of ceramic/FGM/metal composite plate is very gentle. Compared with , when , the maximum tensile stress on the metal surface increases 1.44 times, and the maximum compressive stress on the surface of ceramics increases 1.50 times. The results provide the foundations of theoretical calculation for the design and application of the composite plate.
Frictional Brake Material Reinforced with Sisal Fiber and Glass Fiber Hybrid
Authors: Zeng Ming , Wei Chun , Xiong Xue Mei , Yu Chuan  Bai
Published: November 2010

Asbestos-free frictional material is developed by using phenol formaldehyde resins modified with nano- SiO2 as matrix while surface-treated sisal fiber and glass fiber are used as reinforcement. The friction and wear properties were investigated on Constant speed (D-SM) tester. The abrasion surfaces of composites were observed by scanning electron microscope (SEM). Test result shows that all the properties, such as, friction coefficient and wear can meet the GB5763-2008 requirement. When the sisal fiber and glass fiber hybrid ratio is 2:1, the composite has the high mechanical property, suitable and stable coefficient of friction and relatively low wearability especially at high temperature.
Low Temperature Fired Ferrite/Ceramic Composite Materials and their Permeability Spectra
Authors: Ling Wei Wei , Zhang Huai Wu , Li Yuan Xun , Liu Ying Li
Published: November 2010

Ni-Cu-Zn ferrite/CaTiO3 and Ni-Cu-Zn ferrite/BaTiO3 composites which can be applied in low temperature co-fired ceramic (LTCC) technology were synthesized by conventional solid-state reaction lower than 950°C. The complex permeability spectra of the above two composites have been investigated. The contribution of spin rotation and domain wall motion to the permeability spectra was estimated by the numerical fitting of measured data to the relevant formula. Influence of two types of magnetizing processes on the permeability of different composites has been analyzed combining with the variation of microstructures.
Grafting Milk Protein on Polyester Fabric Encased with Hydroxide and Wearability of Polyester Fabric Grafted Milk Protein
Authors: Zhang Guang Xian , Hu Wei , Tian Shun , Peng Yan , Zeng Xi Ping , Zhang Feng Xiu , Jing Ling Xiao , Duan Xuan Ren
Published: November 2010

Although Polyester has outstanding wearability, it only has few reacting functional groups in its surface, so protein can not be grafted firmly on polyester fiber surface. Therefore few reports are about grafting protein on polyester fiber’s surface. In this study, the surface of polyester was encased with hydroxide. Then the polyester fibers could be grafted with milk protein by using a synthetic crosslinkages compound. The structure of grafting milk protein polyester fabric was studied by SEM, and the wearability was measured too. Experimental results showed that milk protein could be grafted firmly on polyester through encasing and crosslinking technology. Milk protein could not be washed in the washing process. With the increase of grafted milk protein rate, the whiteness of polyester almost did not change; the cockle elasticity increased firstly, and then decreased, flexural stiffness and hygroscopicity property increased monotonously, moisture permeability increased firstly and decreased subsequently, and antistatic property increased greatly. Encasing hydroxide and grafting milk protein technology is an effective method to produce high functional polyester fabrics.
Damage Theoretical Analysis of 2.5D C/SiC Composites under Tensile and Shear Loading
Authors: Chang Yan Jun , Zhang Ke Shi , Jiao Gui Qiong , Chen Jian Yun
Published: November 2010

An anisotropic damage constitutive model is developed to describe the damage behavior of C/SiC composites. Different kinematic and isotropic hardening functions were employed in damage yield function to describe accurately the damage nonlinear hardening. The damage variable is defined by the principle of energy equivalence. The degradation of stiffness and the unrecoverable deformation induced by micro-crack propagation were considered in this model. The constants of constitutive model are identified and the damage evolution processes under tensile and shear loading. Uniaxial tension and shear tests have been used to valid the constitutive model to C/SiC composites.