bluuebunny/crossref_metadata_2025 huggingface dataset:
Densification Behavior and Pores Evolution of Selective Laser Sintering Parts during Post Microwave Sintering Process
Authors: Lin Shao Jiang , Wang Sai Yu
Published: August 2011

This work compared the densification behavior and pores evolution of two kinds of samples (15% and 35% initial porosity stainless steels parts) prepared by selective laser sintering. The results show that post microwave sintering process results in an increase of the density of sample. At the low sintering temperature (1200°C, 1300°C), the low porosity can lead to high density in the final sintered sample. As the sintering temperature reaches 1400°C, however, the sample with 35% initial porosity could be sintered to the higher final density than that of the sample with 15% initial porosity. The results also indicate that the initial porosity has a great effect on the number of pores, pore size, pore shape and the distribution of pores during post sintering process.
Dynamic Crushing Behavior of the High-Density Closed-Cell Foams
Authors: Chen Wei , Lu Zi Xing
Published: August 2011

The face-centered cubic model is used to investigate the dynamic crushing behavior of high density closed-cell foams. The influences of the constant loading rate and the specimen aspect ratio on the crushing stress were discussed. It is demonstrated that the crushing stress is more sensitive to the constant loading rate than the specimen aspect ratio. To describe the dynamic crushing behavior of the foam theoretically, the idealized rigid-perfectly plastic-locking (RPPL) stress-strain model is extended to a more general case, in which both the density and the cross-section area are discontinuous. The good agreement between the finite element results and theoretical results confirms that the dynamic crushing behavior of foam can be described by the modified RPPL stress-strain model.
Molecularly Imprinted Polymer Prepared by Precipitation Polymerization for Quercetin
Authors: Qiu Hua Min , Luo Chuan Nan , Fan Lu Lu , Lv Zhen , Lu Fu Guang
Published: August 2011

In this paper, molecular imprinted polymer for quercetin was synthesized by precipitation polymerization with acrylamide as functional monomer, ethylene glycol dimethacrylate as cross-linker, 2,2-azobisisobutyronitrile as initiator and acetone as the solvent. The polymers’ adsorption properties were characterized. As results shown that the synthesized imprinted polymer is microspheres with particle size in the nanometer scale, the adsorption capacity of quercetin imprinted polymers is 1.1×10-5mol/g, adsorption temperature is 60°C, adsorption time is 30 min. The molecular imprinting technology was introduced in interference test with a satisfactory result in selectivity.
A Novel Thermoviscosifying Water-Soluble Polymer for Enhancing Oil Recovery from High-Temperature and High-Salinity Oil Reservoirs
Authors: Wang Yu , Lu Zhi Yong , Han Yu Gui , Feng Yu Jun , Tang Chong Li
Published: August 2011

Polymer flooding represents one of the most efficient processes to enhance oil recovery, but the poor thermostability and salt tolerance of the currently-used partially hydrolyzed polyacrylamide (HPAM) impeded its use in high-temperature and high-salinity oil reservoirs. “Smart” thermoviscosifying polymers (TVPs) may overcome the deficiencies of HPAM. Steady and dynamic rheological behaviors against temperature of a novel TVP were examined in this work in comparison with a commercial HPAM polymer. It was found when increasing temperature, both apparent viscosity and elastic modulus increase for TVP aqueous solution, but decrease for HPAM solution. The results indicate that TVP shows some potential to be used in enhancing oil recovery from high-temperature and high-salinity oil reservoirs.
Vacuum-Free Stirring Brazing of SiCP/A356 Composites and Aluminum Alloy Using Semisolid Filler Metal with Low Solid Fraction
Authors: Xu Hui Bin , Luo Quan Xiang , Xing Liang , Zhou Bo Fang , Zeng You Liang , Du Chang Hua
Published: August 2011

This paper explores the brazing process of SiCp/A356 composites and aluminum alloy using semisolid metal. The two substrates were heated up to the semisolid temperature range of Zn-Al filler metal in the joint region by a resistance heating plate. In order to mix the filler metal with the base metal of both sides to be a single uniform joint, a stirrer was introduced into the weld seam. After stirring, specimens were sectioned for analysis of macro- and micro-structures along the weld region. The research shows that SiCp/A356 composites and aluminum can be local joined with semi-solid filler metal. It can be found that part of the oxide film on the interface of the base metal was disrupted and removed through the observation by SEM. The metallurgical bonds can be formed between the filler metal and the base materials. Moreover, the oxide film of surface of aluminum alloy disrupted and removed was easier than that of surface of composites with existing of Sic particle. The joint microstructure with globular α-Al grain enclosed by rich-Zn phase can be obtained after stirring brazing.
Effects of Viscosity Modifying Admixtures on the Workability of Self-Compacting Concrete
Authors: Ma Bao Guo , Wang Hui Xian , Xiao Jia , Li Li Xia , Cheng Zhi Bin
Published: August 2011

Viscosity modifying admixtures (VMA), known as an important component, are water-soluble polymers that can increase the viscosity and cohesion of self-compacting concrete( SCC). This article presents the effect of four different types of VMA on the workability of SCC , which including flowability, filling ability, passing ability and segregation resistance ability of the fresh concrete. The results show that the low viscosity of VMA satisfies the workability requirement of fresh properties of SCC.
Integrated Performance Optimization of Truck Suspension Parameters Based on Gradient Optimization
Authors: Yang Jian Wei , Dong Jun Zhe , Zhang Guang Ye
Published: August 2011

In order to ensure the truth and feasibility of constraints during the optimization of suspension parameters, a method, combining gradient optimization with ADAMS, is put forward to optimize the suspension parameters of the truck, which can improve its running comfort and friendliness. Based on the evaluating indicators of ride comfort and road-friendliness, the impacts of suspension parameters on ride comfort and vehicle damage on the road were researched. According to multi-body dynamics theory, a virtual prototype model of the truck is built by ADAMS. The effect of traveling speed, suspension spring stiffness and shock absorber damping on vehicle ride comfort and road friendliness was analyzed. Then the suspension parameters, in favor of ride comfort and road friendliness, were obtained. It is helpful to design the suspension of truck.
The Influence of Pore Structure on Internal Flow Field Shear Stress within Scaffold
Authors: Yao Yuan , Chen Wei Deng , Jin Wen Yu
Published: August 2011

How to design appropriate scaffold structure and mechanical environment for vitro culture of bone tissues are the focus of bone tissue engineering research. The mechanical properties of internal flow field within the scaffold are the most important factors in the scaffold design and cultivation. In order to identify the relationship between perfusion parameters, pore structure and the internal shear stress distribution, a computational scaffold model is proposed, which uses ellipsoid as the basic pore-making unit and uses major axis as the shape control parameter. Computational fluid dynamics simulation shows that the average shear stress on pore walls is linear with the major axis when the bone scaffold porosity is maintained in the same level, and the distribution of shear stress trends to be more uniform with the increase of the major axis. The experiments provide clear relationship between the structure parameter and the distribution of shear stress. And this can be used to improve the pore structure design.
Fabrication of Ti-43Al-5V-4Nb Intermetallic Compounds by Forging Using the Blended Elemental Powders
Authors: Chen Yu Yong , Su Yong Jun , Kong Fan Tao , Zhang De Liang
Published: August 2011

Ti-43Al-5V-4Nb (at.%) intermetallic compounds with fully lamellar structure were fabricated by forging method without canning using the blended elemental powders. The process route consisted of powder blending, compacting, sintering and final fabrication by hot forging. During sintering, there existed expansion, which is detrimental to forging process. In order to overcome the difficulty, two-step forging was introduced. The total reduction of two-step forging was up to 65%. Nearly fully lamellar structure of TiAl alloy was obtained. Overall, an optimized and potentially lower cost processing route could be identified.
High-Performance Silica/Epoxy Resin Hybrid Materials Prepared by In Situ Sol-Gel Process
Authors: Jiao Jian , Zou Liang , Liu Pan Bo , Wu Guang Li
Published: August 2011

Silica/epoxy resin hybrid materials are prepared with tetraethylorthosilicate (Si(OC2H5)4, TEOS) and γ-aminoproplytriethyoxysiliane (H2N(CH2)3Si(OC2H5)3, APTES) as the silica sources, epoxy resin as the polymer matrix, by the means of in-suit sol-gel method. The dosages of TEOS and APTES in preparation of hybrid materials, and the sol-gel temperature for silica resources are discussed to make sure of the influence of the structure and properties on hybrid materials. The dispersion of Silica in the epoxy resin are examined by transmission electron microscopy (TEM).The image of fracture surfaces of hybrid materials are examined by scanning electron microscopy (SEM). The glass transmission temperatures (Tg) are tested by differential scanning calorimeter (DSC) to characterize the heat resistance of hybrid materials. The optimum mechanical performance and heat resistance for silica/epoxy resin hybrid materials are achieved with 3wt% TEOS and APTES 2wt% employed in this materials when sol-gel temperature is 60°C. In general, the mechanical and thermal properties of the hybrid materials were improved greatly as compared with the pure epoxy resin.
Investigation of Application Conditions of Barium/Strontium Scale Inhibitor in Oilfields
Authors: Ke Qiang , Liang Fa Shu
Published: August 2011

In response to the serious barium / strontium – scale in oilfields, we simulated oilfield conditions and investigated the scale inhibition performance of several common scale inhibitors to barium and strontium, by following the protocol from Evaluation Methods of Anti-Scale Agent for Oilfield Use, Petroleum Gas Standards of People’s Republic of China SY/T 5673. The most effective scale inhibitor CD-1 was screened out. With CD-1 as barium / strontium scale inhibitor in the static anti-scale analytical experiments, the dependence of scale inhibition performance on scale inhibitor concentration, saltiness, temperature, time and the system pH was investigated. The application conditions of barium / strontium scale inhibitor in real petroleum and gas field was obtained. Under the optimized application conditions, the mixture scale inhibitor had better scale inhibition efficiency than CD-1 alone.
Relationship between Technics and Properties during PAN Precursors Formation Process
Authors: Ji Bao Hua
Published: August 2011

In order to release the relationship between technics variables and properties of PAN fiber, the evolvement of crystalline structure of PAN fiber during the wet spinning process was studied by X-ray diffraction(XRD), the measurement of the solvent residuals, boiling-water shrinkage and breaking tenacity. It is found that the drawing and removal of solvent can improve the tenacity, especially the drawing can improve degree of orientation and crystallinity, and the collapse process can stabilize the orientation and crystalline structure.
Study on Viscosity of Poly(Acrylic Acid-Co-Acrylamide) Concentrated Solution with Different Potential Crosslinking Agent
Authors: Ding Yuan Rong , Li Zhi Wei , Su He Qun , Ding Yang
Published: August 2011

Poly(acrylic acid-co-acrylamide) has large number of ionic and nonionic hydrophilic groups, such making the rheological behavior of its solution complex. In this research, four different potential crosslinking agents which contains activating hydroxyl group and unsaturated bond were introduced into the poly(acrylic acid-co-acrylamide) polymer during aqueous solution radical polymerizations. Rotary viscosimeter was chosen to characterize the apparent viscosity of poly(acrylic acid-co-acrylamide) concentrated solutions. Temperature, concentration of the aqueous concentrated solutions and proportion of potential crosslinking agent are the most important factors. Results shows that the apparent viscosity of PAAM concentrated solution decreases with the increase of temperature, the decreases of concentration of the aqueous concentrated solutions and the proportion of potential crosslinking agent.
Data-Compensation Based Dynamic Robust Design for Partially Unknown System
Authors: Lu Xin Jiang , Huang Ming Hui , Chen Min , Li Yi Bo
Published: August 2011

In practical application, a nominal model is often used to approximate the design of industrial system. This approximation could make the traditional design method less effective due to the existence of model uncertainty. In this paper, a novel robust design approach is proposed to design the robustness of the dynamic system under model uncertainty. The key idea of this proposed method is that it integrates the advantages of both the model-based dynamic robust design and the data-based uncertainty compensation. A simulation example is conducted to demonstrate the effectiveness of the proposed robust design method.
Research on the Influence of the Road-Friendliness by Semi-Active Suspension
Authors: Li Jie , Zhu Ai Hua , Zeng Heng , Li Jun Peng
Published: August 2011

In order to improve the road-friendliness of vehicle, this paper studies vehicle dynamic performance through establishing car model in ADAMS, hybrid control strategy in SIMULINK and the use of joint simulation technology. By using dynamic load coefficient and the road-friendliness index of dynamic load stress factor evaluate the road-friendliness of the semi-active suspension system with hybrid control strategy. The research shows that the road-friendliness will be better when the damping force distribution coefficient for 0.2 ~ 0.6.
Preparation and Upconversion Luminescence Properties of Tb3+-Yb3+ Co-Doped Phosphate Inverse Opals
Authors: Zhu Kan , Yang Zheng Wen , Yan Dong , Song Zhi Guo , Zhou Da Cheng , Wang Rong Fei , Qiu Jian Bei
Published: August 2011

Upconversion (UC) luminescence photonic band gap materials Tb3+-Yb3+ co-doped phosphate inverse opal photonic crystals were prepared by a self-assembly technique in combination with a sol-gel method. The effect of photonic band gap on UC luminescence was investigated in inverse opals. Effective suppression of the UC luminescence was inspected if the photonic band gap overlapped with the emission band of Tb3+ ions.
Effect of Bi2O3 Addition on the Physical and Electrical Properties of Lead-Free (Na0.5K0.5)NbO3 -( Na0.5Bi0.5)TiO3 Ceramics
Authors: Wang Chun Huy
Published: August 2011

In this paper, the effects of Bi2O3addition on the electrical and physical properties of 0.98(Na0.5K0.5)NbO3-0.02(Na0.5Bi0.5)TiO3 were investigated. The 0.98(Na0.5K0.5)NbO3-0.02(Na0.5Bi0.5)TiO3[0.98NKN-0.02NBT] ceramics with the addition of 0~0.5 wt% Bi2O3have been prepared following the conventional mixed oxide process. X-ray diffraction analysis revealed that, during sintering, all of the (Na0.5Bi0.5)TiO3diffuse into the lattice of ((Na0.5Bi0.5))NbO3to form a solid solution, in which a orthorhombic phase with a perovskite structure was found. For 0.98NKN-0.02NBT ceramics by doping 0.1 wt% Bi2O3, the poled dielectric constant (K33T) and the electromechanical coupling coefficients of the planar mode kpreach 684 and 0.38, respectively, after sintering at 1100 °C for 3 h. Our results show that 0.98NKN-0.02NBT with the addition of 0.1 wt% Bi2O3is a good lead-free piezoelectric ceramic.
Finite Element Analysis and Experimental Verification on Mechanical Properties of Steel Mash Reinforced HDPE Composite Materials
Authors: Qian Xin , Jin Yang Fu , Zhou Mi , Sun Jia Na
Published: August 2011

Thorough constructing steel-plastic composite material model and using ANSYS finite element analysis software, this research make a CAE analysis and experimental verification to the elastic modulus and flexural modulus of reinforced HDPE composites under different steel structures. The research found that the tensile modulus of steel mash reinforced HDPE linearly increases with the increase of steel wire diameter and the number of steel wires on the specimen width. When the steel wire diameter is 3mm, the tensile modulus is up to 10 times of the pure HDPE’s. The number of steel wires on the specimen length does not affect the tensile modulus. Similarly, the flexural modulus of the composite material also linearly increases with the increase of steel wire diameter and the number of steel wires on the specimen width. However, when the steel wire diameter is 3mm, the flexural modulus is only 2 times of the pure HDPE’s. The data simulated by ANSYS software has a very good agreement with the experiment results. Therefore it can be applied to the actual design.
Response of Ultrasonic Wave Velocity to Wood Structure Defect of Korean Pine
Authors: Wang Na , Wang Li Hai
Published: August 2011

An experiment was conducted to Korean pine specimen by ultrasonic tester. The effect of hole size and holes amount in axial direction of wood as well as the distribution of end holes on ultrasonic wave velocity were respectively studied. A comparison test was carried out between the specimens of one hole defect and no defect with different lengths. Then regression analysis of the relation between hole size and ultrasonic wave velocity was done using SPSS software. The experimental results show that the length of wood components has significant effect on ultrasonic wave velocity. The ultrasonic wave velocity has negative correlation with hole size and holes amount. End hole has no significant effect on ultrasonic wave velocity. This research will provide some theoretical basis for the detection of internal defects in wood materials, material evaluation and the evaluation of physical and mechanical properties testing.
Effect of Moisture Absorption on the Bending Strength of Carbon/Epoxy Composites with Voids
Authors: Zhang A Ying , Zhang Jian She , Wang Jia Zhi , Li Di Hong , Zhang Dong Xing , Xiao Hai Ying , Jia Jin
Published: August 2011

The effects of voids on the bending strength of T300/914 laminates that exposed to room temperature, hygrothermal and drying environment was discussed in this paper. The experimental results revealed that the saturated moisture content and the rate of water uptake increased with porosity increasing from 0.71% to 1.50%, which proved that voids facilitate moisture absorption. The bending strength of the unaged, aged and dried specimens were characterized and analyzed. The results revealed that the bending strength of the aged specimens decreased with the increasing void contents and immersion time. Compared to the unaged specimens, the bending strength of the aged specimens decreased 13.33% and 18.78% with porosity of 0.71% and 1.50%, respectively. The bending strength of the dried specimens was higher than that of the aged specimens and lower than that of the unaged specimens in the case of similar porosity.
Study for Seeking Optimal Mix Proportion of Resin Concrete
Authors: Wu Long , Hu Yan Hua , Qiao Xue Tao
Published: August 2011

In the study, uniform design method is used to define the mix proportion of resin concrete. According to results obtained from the experiment, the optimal mix proportion of resin concrete can be got through regression analysis by using SPSS software, and MATLAB software together. The methods not only reduce the number of tests and the test costs greatly, but also provide an accurate and reliable design concept for the application of resin concrete in practical engineering.
Study on Coloring Protective Composite Oxide Film on Aluminum Surface
Authors: Wang Li Xian , Guo Qiang , Pan Guo Liang , Guo Chun Ying
Published: August 2011

This work presents a preparation of composite aluminum anodizing oxide film and its coloring process. When a kind of ultra fine silicon particle with negative charge was doped into the micropores of film by electrochemical method, the obtained composite film has bulk density of 3.53 g•cm-3, cavity ratio of 10.6 % and thickness of over 20 µm. Compared to traditional aluminum anodizing oxide films, the obtained new film gives higher hardness and mechanical properties. XRD analysis showed that silicon particles in composite oxide film were mainly composed of feldspar NaAlSi3O8. Furthermore, a kind of malonamide azo-colorant was introduced into the micropores of composite oxide film by in-situ synthesis to give various colors, where the malonyl group was as a bridge between aluminum oxide film and diazonium group. Properties evluation tests shows that the obtained colored decoration film exhibits high resistance to heat, salt-fog, mold and nature corrosion. Therefore, the composite aluminum anodizing oxide film is a promising candidate for application in stringent condition needing high protection as well as bright color.
Research on Glass Fiber Bars of the Shear Property after High Temperature
Authors: Fu Ya Nan , Zhao Jun , Cheng Long Fei , Mao Hai Tao
Published: August 2011

Through 14 group 42 individual specimens of glass fiber bars which diameter is ф10 and ф12 at 20°C, 100°C, 150°C, 200°C, 250°C, 300°C, 350°C, after high temperature, shear test is done , the changing nature and influent factor are analyzed. It indicates from the test results: the surface colour of glass fiber bars is deepening with temperature increasing, becourse combine、decomposition are aggravating with temperature increasing; shear strength is increasing with the diameter getting large; more than certain temperature the glass fiber bars of shear strength is suden drawdown.
Coating Technique’s Application in the Improvement of Mechanical Behavior of Polyester Textile in Corrosive Environment
Authors: Liu Guo Ning , Zhao Hua Dong , Wang He Zheng , Dong Jing Ru , Zhao Ming Hao
Published: August 2011

Polyester textiles usually have excellent mechanical properties. However, their mechanical behaviors under extreme conditions such as in the environment with high ozone concentration usually decay after a certain time period. Aiming at increasing the mechanical behavior of commercial polyester textiles under extreme conditions, a PET thin film coated with pure aluminum (Al) on its surface has been introduced as the top layer of the fabricated material with polyester textile as the middle layer. Main purpose of the study is to evaluate the role of aluminum thin film on the surface in improving the mechanical behavior of the polyester textiles after they have been exposed in the environment with extremely high concentration of ozone gas.
The Variable Cross-Section Helix Turning Trajectory Algorithm Used on the Middle-Convex and Varying Ellipse Piston Skirt
Authors: Guo Yin Biao , Huang Hai Bin , Lin Jian Hua
Published: August 2011

In order to turning the skirt of middle-convex and varying ellipse piston, this paper proposes a Variable Cross-section Helix Turning Trajectory (VCHTT) algorithm. it divide the turning trajectory of the piston skirt into transversal and helix, then obtain the coordinates of ellipse transversal cutter-contact points on the basis of centric polar radius arc interpolation (CPRAI) algorithm, and uses line surface intersection method to obtain the coordinates of helix cutter-contact points on the middle-convex and varying ellipse piston skirt. At last，merge two coordinates matrices to obtain the final coordinate surface of cutter-contact points of turning tool. With comparison, it finds that the VCHTT algorithm improves the interpolation accuracy by 0.04um than other methods.
Electrochemical Performance of New Ferroalloy Electrode of RE2FeSb2 (RE = Y, Dy, Er)
Authors: Xia Xiu Wen , Zhang Xin Qin , He Wei
Published: August 2011

Rare earth antimonide stoichiometric compounds RE2FeSb2(RE=Y, Dy, Er) were prepared and examined by X-ray diffraction technique. XRD analysis showed that these alloys were crystallized in cubic RESb-type structure. The electrochemical properties of these alloys such as discharge capacity and cycling performance were investigated by battery testing instruments in alkaline electrolyte. Electrochemical tests discovered that the alloys RE2FeSb2(RE=Y, Dy, Er) had two clear and wide discharge potential ranges. Furthermore, the first charge and discharge cycle showed that the discharge capacities of RE2FeSb2(RE=Y, Dy, Er) were about 12.8,15.1,16.0 electron/formula, respectively. The ferroalloy electrode of RE2FeSb2(RE=Y, Dy, Er) had latent superiority in electrochemical properties.
Complexing Agent on the Surface of Magnesium Alloy Plating of Ni-B Alloy
Authors: Cai Yu , Chang Zhen Zhen , Chen Chun Mei , Bai Yu Ting , Lin Ya Wei , Li Zhi Qiang
Published: August 2011

CPM9V high speed steel(HSS) ring billet was prepared by spray forming(SF), the yield is 83.5%, porosity is 0.8%, spray forming preparation method and technological parameter were illustrated. The microstructure and carbide morphology on the different position of billet were observed. The results show that carbide particles have small size, regular shape and uniform distribution, alloy element without segregation. There are some pores and defects in the position of ring billet closed to deposition substrate, come from spray forming instability beginning stage.
Electrochemical Synthesis and Characterization of NiFe/Au Multisegmented Nanowires
Authors: Sri Ramulu Torati , Venu Reddy , Anandakumar Sarella , Sinha Brajalal , Yoon Seok Soo , Kim Cheol Gi
Published: August 2011

This paper represents the synthesis and characterization of NiFe single segment and NiFe/Au multisegmented nanowires. We fabricated these nanowires by electrodeposition technique using track etched polycarbonate membrane as a template with a nominal pore diameter of 50 nm. In recent years, much attention has been drawn to magnetic and nonmagnetic multisegmented nanowires because the magnetic properties of the nanowires can be useful for the manipulation and detection of biomolecules in a suspension by the application of relatively small magnetic fields where as the nonmagnetic segment has biocompatibility with high surface functionality. So in this work we studied the growth of NiFe/Au multisegmented nanowires. The length of the nanowires is found to be very uniform. The magnetic properties are measured by VSM. The measured coercivity and saturation magnetization of NiFe/Au multisegmented nanowires are lower than the NiFe nanowires. The structural morphology was observed by SEM. The EDS result shows the purity of both NiFe nanowires and NiFe/Au multisegmented nanowires.
Performance Study of Aerostatic Bearings with Arrayed Microhole Restrictors
Authors: Li Peng , Chen Han , Chen Xue Dong
Published: August 2011

Micro-vibration of aerostatic bearings has been the bottleneck in the improvement of the moving and positioning accuracy of ultra-precision fabrication and metrology equipments. In this study, a new type of aerostatic bearing restrictor has been proposed. The prototype of arrayed microhole restrictor, instead of the conventional single hole restrictor was developed with the aim of reducing the harmful micro-vibration of aerostatic bearings. Computational fluid dynamics (CFD) was employed to numerically calculate the air flow field. It is found that the employment of arrayed microhole restrictors can reduce the amount of micro-vibration while maintain the load carrying capacity and stiffness of the aerostatic bearing. Experimental measurement of the micro-vibration confirms the effectiveness of this new type of restrictor.
Electrochemical Polymerization and Characterization of Poly(3-Methylthiophene) in Pure Ionic Liquids
Authors: Wang Xia , Feng Li Jin , Yang Zhi Ai , Ma Rong , Song Xu Chun
Published: August 2011

Poly(3-methylthiophene) (PMeT) was electrochemically synthesized on an ITO surface in the ionic liquid 1-butyl-3-metyllimidazolium hexafluorophosphate ([BMIM]PF6) by a potentiodynamic polymerization method. The poly(3-methylthiophene) was characterized by fourier-transform infrared spectroscopy (FT-IR) and energy-dispersive X-ray analysis(EDS). Scanning electron microscopy (SEM) was used to show the morphology of the PMeT film. Electrochemical properties of the prepared film were characterized by cyclic voltammetry.
Oxidation and Melting Characterizations of AZ91D Granules during In Situ Melting
Authors: Jafari Hassan , Idris Mohd Hasbullah , Ourdjini Ali , Farahany Saeed
Published: August 2011

In this research, the oxidation and melting behaviour of AZ91D magnesium alloy granules was investigated throughout using in-situ melting technique when the granules were covered by flux. The granules were heated inside an electrical resistance furnace at four different temperatures of 650, 700, 750 and 800 °C for 30 min. Thermal analysis was used to detect the granules characteristic temperatures during the technique. The products of the heating process were examined visually and characterized by scanning electron microscopy and energy dispersive X-ray spectroscopy. The results showed that due to occurrence of severe oxidation and combustion, particularly at 800 °C, a significant amount of the granules transformed to a powdered state. The presence of the mould materials within the oxidation residue was detected indicating that severe mould-magnesium reaction occurred during heating. It was found that the granules melted during the heating process. However, the presence of oxides on the granules prevented them from fusing to form a single melt.
Effect of Cladding Material on Residual Stress in Quenched Aluminum Alloy Plate
Authors: Gong Hai , Wu Yun Xin , Wu Zhong Huai , Li Yi Hua
Published: August 2011

Using finite element method, a quenching analysis of 7075 aluminum alloy thick plate is carried out. The effect of surface heat transfer coefficient and plate thickness on residual stress, and the effect of cladding material on residual stress are discussed. It shows that the bigger surface heat transfer coefficient or thickness is, the bigger the residual stress is, and the residual stress significantly reduces while the cladding material exists. Experiments validated the simulation results.
Regression Analysis and Determination of Activity Coefficients of Cd-Pb Alloy
Authors: Yao Shun Zhong , Dai Yong Nian , Huang Hao , Wan Xiao Hong
Published: August 2011

Chemical compositions of Cadmium and lead were measured with conditions that the temperature between 400-700°C and remaining pressure of 10-60 Pa as in which Materials containing Cadmium and lead evaporate. Activity coefficients of cadmium and lead were calculated using the generalized least squares（GLS）, three relations were deduced in Cd-Pb system，namely relation between activity coefficients and temperatures, relation between activity coefficients and chemical compositions, and that of activity coefficients and temperatures together with chemical compositions. This article provides a theoretical reference data for separation of alloys in cadmium systems.
The Solute Redistribution during Solidification of Multi-Component Alloys
Authors: He Zhi , Zhou Hao Bin , Liu Yan Ming , Li Lan Yun
Published: August 2011

The solution redistribution was an important phenomenon during the solidification of multi-component alloys. The improvements of the solute redistribution were considered in this paper especial in the simulation processes. The models of Gibbs free energy were taken into three kinds such as pure materials, the substitutional solution and the sublattice. Calculating the Gibbs free energy of the system, the solute redistribution coefficients could be calculated. The simulated results of Al-Cu binary and Al-Si-Mg ternary alloys agree well with the experimental results.
Effect of Vanadium and Niobium on the Microstructure of Carbide Reinforced Indefinite Chilled Cast Rolls
Authors: Huang Gen Zhe , Li Zeng Hui
Published: August 2011

In the present work, effects of elements vanadium and niobium on the microstructure of the conventional indefinite chilled rolls made by small vertical centrifugal caster were investigated, using optical microscopy, Scanning Electron Microscopy (SEM, Jeol 6400), Energy Dispersive X-ray Spectroscopy (EDXS, Cu-K radiation) to identify the type, morphology, and to measure the volume fraction and the distribution of carbides and graphites formed during solidification. Microstructural analysis indicates that, the amount of graphite is dramatically reduced by adding V element. The volume fraction of the square-like carbides NbC increases with the Nb content increasing. However, if Nb content is over a critical point, large amount of the square-like NbC carbide can be seriously segregated in the out part of the section.
Effect of Additives on Desulfurization Capability of CAS-OB Refining Ladle Slag
Authors: Wang Hong Ming , Zhang Ting Wang , Yang Li Li , Yan Yong Qi , Zhu Hua
Published: August 2011

To avoid slag sticking onto the ladle snorkel during the CAS-OB refining and alloying process, CaO-B2O3 and CaO-CaF2 were respectively employed as modifiers added into the ladle slag. The desulfurization capability of modified slag was investigated. The results of experiments on sulphur partition equilibrium between metal and slag indicate that the sulphur content of metal can be further decreased by the modified slag. When CaO-B2O3 is used as additive and the mass ratio of CaO to B2O3 is 1:1, the desulfurization ratio of slag to liquid steel is 50%, the final sulphur content can be controlled at 0.002%. The efficiency of desulfurization is fine. When CaO- CaF2 is employed as additive and the mass ratio of CaF2 to CaO is 2:8, the final sulphur content of metal can be controlled lower than 0.004%, the efficiency of desulfurization is also acceptable.
Comparison of Effects of B2O3 and CaF2 on Metallurgical Properties of High Basicity CaO-Based Flux
Authors: Wang Hong Ming , Yang Li Li , Zhu Hua , Yan Yong Qi
Published: August 2011

B2O3 is employed as fluxing agent of high basicity CaO-based flux to substitute for CaF2. The effects of B2O3 and CaF2 on the metallurgy properties of CaO-based flux were investigated. The results indicate that the fluxing action of B2O3 is better than that of CaF2. For the high basicity CaO-based flux, when CaF2 is substituted with B2O3, the melting temperature can be decreased remarkably. Especially, when the mass ratios of CaO/SiO2 are in range of 5.25~8.0, the flux melting temperature is lower than 1300 °C. The inflection point temperature of flux viscosity-temperature curve is lowered remarkably when B2O3 is employed to substitute for CaF2. Meanwhile, the desulfurization capacity of flux can be improved markedly when CaF2 is substituted with equal mass of B2O3.
Study on Full-Field Stress Analysis for Composite Material Structure Using Lock-in Thermography
Authors: Liu Jun Yan , Liu Xun , Wang Yang
Published: August 2011

This paper describes a set of theoretical and experimental results based on thermoelastic effect measurement from Glass-Fiber-Reinforced-Polymer (GFRP) composite structure for full-filed stress analysis. The sum of the principle stress (The first stress invariant) can be measured by means of thermoelastic stress analysis (TSA), and this method is used to determine the stress concentration of the composite structure. A finite element analysis is proposed to predict the stress distribution for GFRP gluing structure. The lock-in thermography has been applied to measure the structure stress distribution by its high thermal resolution. The experiment was carried out with different GFRP composite structures by lock in thermography. The experimental results show the stress distribution can be measured and evaluated with good accuracies by using of lock-in thermography
Research on Corn Drying Process under Temperature Gradient
Authors: Mai Zhi Wei , Li Chang You , Zhang Ye , Xu Feng Ying , Lu Ying Ling
Published: August 2011

Using a special Test-Bed, the temperature and the grain moisture content variation in different locations was measured continuously, under the condition of maintaining a large temperature difference between two terminals of grain layer. The results show that the temperature gradient can enhance corn-drying process, and there are two modes of the promotion: 1. The temperature difference direct drive the moisture migration; 2. The temperature difference can generate air convection, and accordingly promote the drying rate. However, the speed of moisture migration originated from air convection was much higher than driven by temperature gradient.
Surface Properties of TiN Films on AZ 31 Magnesium Alloys Deposited by Magnetron Sputtering Technique
Authors: Zhu Xiang Rong , Bing Nai Ci , Wei Zhong Ling , Chen Qiu Rong
Published: August 2011

TiN films were deposited on the AZ 31 magnesium alloy substrates by d.c. magnetron sputtering technique. The surface properties of the films were investigated. The scanning electronic microscope observations reveal the dense structure characteristics of as-deposited TiN films. Under 200°C heat treatment for 30 minutes or 4 times’ heat cycles at 85°C for one hour, no structural defects such as cracks are observed on the surface of the films. Adhesion experiment further demonstrates the stability of the film and the strong combination between the film and the substrate. Nano-indentation experiment shows that the average micro-hardness of TiN film reaches 23.85 Gpa. Finally, the corrosion experiments in simulated body fluid initially reveal the degradation property of TiN film.
Effect of Process Parameters on Welding Variables during Linear Friction Welding of Ti-6Al-4V Alloy
Authors: Ma Tie Jun , Chen Xi , Li Wen Ya
Published: August 2011

The orthogonal experimental design was conducted for linear friction welding of Ti-6Al-4V titanium alloy (TC4). The friction power and joint temperature were collected during the welding process. The influence of process parameters on the axial shortening was analyzed. The suitable process parameters were determined by investigating the joint appearance, the requirement of axial shortening and welding variables during welding. The results provide important reference for establishing process parameters of linear friction welding in practice.
Investigation of Lyocell Fibrillated Nanofibers and Papermaking Characteristics
Authors: Tian Yu , Liang Yun , Cui Yan , Zhang Zeng
Published: August 2011

The nanofiber based filtering media, made up of fibers of diameter less than 1000 nm, have been discovered as new filtering media for effective filtrations. The present study has been made of the influence of various process parameters on the fibrillation characteristics of Lyocell fibers which focuses on how the Lyocell fiber changes with the intensity of beating. Meanwhile the drainage properties and media properties of Lyocell fiber with different beating degree are characterized. The results show that the length, diameter, distortion and degree of fibrillation of Lyocell fiber changes obviously by beating, and a mass of nano-fibril appeared after intensive beating. The Lyocell fiber is cut off rapidly at first, and then fibrillateion starts to appear during the process of beating. At the same time, comparing with the length of the fiber, the beating degree of Lyocell fiber is more sensitive to the degree of fibrillation. What’s more, the drainage time of Lyocell fiber with strongly beating is over ten times than that of the original or ratherish beaten one; Comparing with the media made from original or light beaten pulp, media thickness made from the strongly beaten fiber decreases almost two times, tensile strength increases nearly four times, and air permeability decreases about seventy times.This study has shed some light on the major properties of Lyocell fiber and paves the way for further application of Lyocell fiber in filed of high precision filtration media.
Monitoring the Cotton Growth Conditions Based on LAI from Remote Sensing and Expert Knowledge
Authors: Bai Jun Hua , Li Jing , Li Shao Kun
Published: August 2011

To manage the cotton field effectively, the quantitative classification method for cotton growth conditions would be researched based on LAI from remote sensing inversion in the field scale. The experiment was carried out in 2006-2007 in Xinjiang, China, and the eighteen cotton fields were selected as the standard observation station, the 255 quadrats data about LAI were obtained, and three vegetation indexes, including NDVI, PVI, and EVI, were used to estimate LAI by the correlativity between remote sensing and field measurement. The ideal LAI were proposed by the cotton cultivation experts when the cotton filed would realize the high yield, LAI from 2.8 to 3.2 was applicable at the first flowering stage in the research region. All of R2 on LAI estimation from three vegetation indexes got through the extremely significance test but the two models from PVI and EVI had the more excellent estimation ability when LAI was more than 3.0, and the overall estimation level of EVI is highest, RMSE and REPE is 0.67 and 0.12 respectively, and so LAI was retrieved by EVI in the paper. Through LAI inversed by the remote sensing data, the cotton growth conditions was quantitatively translated into three types of small population, classic population, and big population with LAI expert knowledge. The method classifying the cotton growth conditions was demonstrated in the research region in 2006 and 2007. The research results would contribute to the precision management on the cotton filed.
Sensor of Testing Fabric Infiltrate Characteristic
Authors: Gao Xiao Ding , Wang Gang
Published: August 2011

The Sensor and Circuit of testing fabric infiltrate characteristic are designed. By testing capacitance variation ΔC between the sensor and two plates. It can detect the spread of area of the fabric seepage ΔS and determine the seepage rate of the tested fabric. The Calibration testing has been achieved for the Sensor and Circuit. The data is given out. The linear distortion of the testing Sensor and Circuit is smaller than 5%.It can meet the technical requirements of the testing seepage characteristics of textile products.
Study on Transmission Characteristics of Silicon-Based Microstrip Bandpass Filter
Authors: Peng Yu Feng , Zhang Shu Li , Li Yao Hui , Zhao Yue , Lin Si Hong
Published: August 2011

With the development of semiconductor process technology and IC design technology, silicon-based filter technology continuously improved. The filter’s transmission characteristics depend on the dielectric constant, dielectric loss and substrate thickness. This paper studies the frequency response characteristics of transmission coefficient and reflection coefficient of the parallel coupled microstrip bandpass filter, in the condition of silicon-based with different thickness, loss and doped concentration, when the center frequency is 5.75 GHz.
Development of a Novel Self-Adaptive Contacting Ultrasonic Inspecting System for Welding Belt on Pipeline
Authors: Liao Lin Zhi , Chen Qi
Published: August 2011

For the requirement of online ultrasonic inspection for welding belt on pipeline, and the influence of its surface contour error (roundness) on stabilization of the clearance between the probe and the work pieces, a novel self-adaptive contacting ultrasonic scanner is advanced, which makes the ultrasonic wave transmit into the rotational part along with the normal direction of the detecting surface so as to realize online ultrasonic flaw-detection on pipelines. Based on those works, a software system is also developed, which realizes the requirement of online ultrasonic flaw detection process. The practical application proves the developed system can promote both the inspection quality and the efficiency of .welding belt on pipeline.
Design of Intelligent Measure Control System for Thermal Defects
Authors: Wang Ting Ling , Liu Wei
Published: August 2011

An intelligent measure control system is designed to solve the problem of real-time intelligent detection of thermal defects of high voltage equipment at unmanned substations. This system uses a new method that continuous power of CC2530, a ZigBee wireless single chip, is provided by using monocrystalline silicon solar cells and thermoelectric generation modules. This method can also solve the problem that overheat faults can not be alarmed timely when efficiency of solar cells decrease during the continuous rainy days, and can realize real-time wireless detection and remote fault analysis of thermal defects of high voltage equipment. The supervisory programs of the remote PC and the upper computer are designed through VC + +.NET and the communication mode adopts C/S model based on TCP/IP protocols. The image files are saved as JPEG format by CImage class, which implements the real-time transmission of images. All the forgoing advantages provide a technical assurance to the remote and intelligent control of the heat vice of high-voltage equipment in the unmanned substations.
Design of Hydraulic Dynamic Equilibrium in Household Heating System
Authors: Zhou Yang Min , Li Chao , Xu Li Li , Luo Si Yi , Yi Chui Jie
Published: August 2011

The operating mode of large flow quantity and small temperature difference is used in the traditional serial heating system, which results in a serious problem of hydraulic misadjustment, leading to visible temperature difference among different rooms. In this paper, in order to realize the hydraulic dynamic equilibrium of heating system and control of household heating, the automatic flow control valves are used for the control of flow rate. On the basis of theory analysis of hydraulic misadjustment, the results show that: the efficiency of heating system and control of household heating can be improved significantly, as well as the energy saving up to 20%.
A Visualized Investigation of Void Growth and Coalescence in Pure Copper Sheets under Impact Tension
Authors: Ma Dong Fang , Deng Gao Tao , Chen Da Nian , Wu Shan Xing , Wang Huan Ran
Published: August 2011

The multi-tension loading in the optimized tensile split Hopkinson bar tests for pure copper sheets was used to investigating growth and coalescence of drilled voids in pure copper sheets, recorded by a high-speed camera. The results of scanning electron microscopical investigation of the microvoid evolution in recovered pure copper sheets showed void coalescence mechanisms which are similar to that of visualized drilled voids. The semi-empirical relation [8] for void shape evolution under quasi-static tension was compared with our computed results revealing the dynamic and clustering effects on void growth. The possibility of application of Thomason model[9] and Considere’s condition[10] for void coalescence to thermoviscoplatic constitutive model was explored under impact tension. The main effects affecting dynamic growth and coalescence of voids were presented including the geometry (void size, shape, orientation, spacing), the material properties (dynamic constitutive model) and the stress state (impact tension condition).
Fault Diagnosis of CNC Machine Tools Common
Authors: Zhou Quan , Liu Kai
Published: August 2011

CNC machining is a mechanical and electrical integration in the field of typical products , it’s complex structure and variety.To be able to troubleshoot quickly and accurately,reduce economic losses caused by the failure,require staff not only need to have a wealth of theoretical knowledge and practical experience,must also possess a certain amount of fault diagnosis.
Convergence Analysis for the Nested Refinement of Triangular Finite Element
Authors: Wang Qi Sheng , Zhao Yi Gao
Published: August 2011

In this paper, the method of the nested refinement for triangular mesh and some relevant conclusions are considered. The Κ level triangular grid nested refinement on the plan domain Ω and some related properties are discussed , and the convergence results are obtained for the first boundary value problem of Poisson equation under the nested refinement of triangular finite element.