bluuebunny/crossref_metadata_2025 huggingface dataset:
Design of Dual-Core Architecture Industrial Robot Controller Based on FPGA
Authors: Sun Li Gong , Sun Xiang Wen , Xiang Fei , Li Su Juan
Published: July 2011

This paper designs a dual core structure robot controller, using the resource of FPGA and the method of customizing Nios II dual core processor, which utilizes the openness of SOPC, so that satisfies the requirement of openness and real-time. It designs the software and hardware structure of the controller and carries out relative experiments. The results show that the robot controller system is reasonable and feasible.
CFD-Based Design of the Natural Ventilation System of the Traffic Center of T3 in Beijing International Airport
Authors: Ma Jin Sheng , Liu Xin Tao , Zhuang Da Min , Wang Shao Guo
Published: July 2011

According to the ventilation and heat issues of Beijing Capital International Airport T3 Terminal Station Transportation Center (GTC), based on the actual conditions of the building structure, geographical location, climate and other characteristics, the internal environment of temperature and other issues are analyzed and researched. And the relationship of indoor air flow and interior space of the building is established. With methods of CFD, and from the perspective of the Energy Saving and Environmental Protection, natural wind and related technology are utilizes, and natural ventilation and heat transferring guidance systems are designed, so that the internal temperature is reduced and the indoor comfort is improved. Introduction Beijing Capital International Airport is located on a piece of land of Chaoyang District on the northeast of Beijing, 25.35 km from Tiananmen Square. It is the busiest transportation and production major international airports of China, on the most important location, with the largest and most complete equipment. Beijing Capital International Airport T3 Terminal Station Transportation Center (GTC) is located to the south of the T3 Terminal Building, with total construction area of more than 34,000 square meters. 1,2-floors underground are open-large parking garage, the first floor has multi-hub facilities supporting the airport, and the second floor is suburban railway stations. The roof is a glass dome, and used long-span structures. The main functional area is a large space, and the external structure for large area is glass walls. The form is determined by functional requirements of the terminal station and visual and psychological demands of people. More precisely, the form not only is a concrete manifestation of humanized design, but also brings the problem of high energy consumption.
Analysis and Application of Deflection Curve Equation Expressed in Terms of Geometrical Parameters for Compressed Bars
Authors: Zhao Rui , Sun Lu , Li Rui
Published: July 2011

A new solution to geometrically nonlinear problems is presented. It has been found that the deflection curve equation expressed in terms of geometrical parameters for a compressed bar is a result of superposition by an Euler’s curve for two-force member in buckling equilibrium and a deformation equation for two-force member in stable equilibrium. Corresponding with the superposition of deflection curves, the load case of the compressed bar is divided into an axial force with a moment and an axial force with a shear force applied to the two-force member respectively. The analytic principle and the deflection curve equation for compressed bars can be applicable to geometrical nonlinear analysis or buckling problems, which is called analytical methods. The decision rule for the equilibrium property of the deflection curve expressions is presented. Practical applications of analytical methods show that some brief formulas can be obtained in the load case without shear forces.
So42- /ZrO2 Solid Super-Strong Acid Esterification Catalyst Prepared by Supersonic Wave Technique
Authors: Luo Xiao Min , Li Peng Ni , Wu Dong Qiu , Ren Hui Jun
Published: July 2011

SO42-/ZrO2 solid super-strong acid catalyst was prepared by supersonic immersion method and the catalysts were characterized respectively by IR, BET, XRD, Element Analysis and SEM methods. The results showed that the catalyst prepared by supersonic immersion method had the larger specific surface area, the smaller grain size, the looser crystal structure, the higher surface roughness and the more border location and edge locations, which were helpful to increase the number of catalyst activity centers and was used for the esterification of polyethylene glycol oleic acid produced by oleic acid and polyethylene glycol. It also had the higher catalytic activity and longer service life.
An Analysis Method with Equivalent Circuit for the Electrical Effect Induced by Laser Plasma
Authors: Ji Yun Jing , Wang Chun Yong , Bian Bao Min , Li Zhen Hua
Published: July 2011

Electrical effect induced by the laser plasma was investigated with an external tiny probe during Nd:YAG high-power pulse laser ablation on copper target in air. One equivalent circuit for the electrical effect induced by laser plasma was proposed. Based on the equivalent circuit, a new theoretical explanation of the signal generation mechanism is proposed, and the reason that the distribution of electrical signal wave is strongly dependent on the probe distance was discussed. Further the observed signal peak polarity overturn was explained.
Effect of Some Factors on Fabrication of Clad Strip by a Roll Caster
Authors: Haga Toshio , Nakamura R. , Ymabayashi T , Tsuge T , Kumai S. , Watari H.
Published: July 2011

A vertical tandem positioned twin roll caster and an unequal diameter twin roll caster were used in this study. Factors which affected the connecting of the strips in the fabrication using a roll caster were investigated. They were influences of oxide film, roll-load (separating force) and temperature of a strip. In the clad-strip casting by the roll caster, the connecting could be operated before the oxide film became firmly. Mn was useful element to prevent the oxidation. The roll-load could break the oxide film existed on the strip surface. Prevention of the occurrence of the oxide film was important to make strip connecting condition firm. In the casting of the clad strip using an unequal diameter twin roll caster, strips did not contact to the atomosphere before connecting.
A Method for Calculating Deformation of Long-Distance Pipeline Based on Strain
Authors: Yi Li Qi , Ding Ke Qin , Qian Cai Fu
Published: July 2011

In this paper, a method for calculating deformation of long-distance pipeline by using strain is presented. We analyze the pipe as a beam. According to geometric equation of beam’s large deformation, we establish the relationship between strain and displacement. With numerical method, beam’s deformation can be got by using different positions’ strain of a cross-section and a generatrix.
The GPU-Based Parallel Implementation of Phase Information Extraction of Multi-View Images
Authors: Zhang Ju Tao , Yan Jian Feng , Gong Sheng Rong , Pu Dong Lin
Published: July 2011

The eccentricity coextrusion flow of polymer melt was analyzed based on finite element simulations. Such simulated results as the fields of flow velocity, pressure and shear stress were obtained. Through the analysis of the results, the mechanism of the column interface forming in the axis-symmetry coextrusion flow path was obtained. For the coextrusion flow, if the low viscosity polymer flows near the die wall, the flow would be steady. Whereas, if the polymer with low viscosity is in the core and the high viscosity polymer at the outer region, Which is disadvantage in terms of energy, and the instability flow would occur. This is also accord with the least energy consume theory.
Gear Fault Diagnosis Method Based on Cyclostationary Degree and HMM
Authors: Wu Bin , Kang Jing , Luo Yue Gang
Published: July 2011

This paper proposes a gear fault diagnosis method based on cyclostationary degree and Hidden Markov Model (HMM) theory. By using the demodulation characteristic of cyclostationary degree for AM and FM signals, we extract the characteristic information of the gear working status. This information can be converted into sets of fault feature vector, which is used as the training sample or observed sample of HMM model for gear fault identification. Experimental results show that the gear fault diagnosis method has good recognition result for the four kinds of status of normal, broken teeth, pitting and wear gear.
Comparison in Tribological Properties of YBa2Cu3OX/Ag and Bi2Sr2CaCu2OX/Ag Self-Lubricating Composites
Authors: Tang Hua , Li Wen Jing , Li Chang Sheng
Published: July 2011

The YBa2Cu3Ox/Ag and Bi2Sr2CaCu2Ox/Ag self-lubricating composites were prepared using powder metallurgic method. The crystal structure and morphology of the as-synthesized samples were characterized by XRD and SEM. The YBa2Cu3Ox/Ag and Bi2Sr2CaCu2Ox/Ag self-lubricating composites were found to compose of superconductor phase and Ag phase. The tribological properties from ultra-low temperature to room temperature of the composites were studied by pin-on-disk friction test. It was found that the friction coefficients of pure YBa2Cu3Ox(YBCO) and Bi2Sr2CaCu2Ox(BSCCO) were both dropped abruptly when the temperature cooled below the superconducting transition temperature. At room temperature, the friction coefficient of pure YBa2Cu3Oxis 0.68~0.95, when mixing 15wt% Ag, the friction coefficient of the sample decreased to the lowest value 0.11. The friction coefficient of pure Bi2Sr2CaCu2Ox is 0.15~0.17, When Ag content reach 10wt%, the coefficient was lowest (average value is 0.13). The addition of appropriate amount of Ag obviously improve the tribological property of YBCO, while only slightly meliorate that of BSCO. On the other hand, the YBCO/Ag composites exhibit better tribological properties than BSCCO/Ag composites at higher load under the same experimental condition.
Study on the Coordination Compound of Human-Like Collagen with Copper (II)
Authors: Yu Yuan Yuan , Fan Dai Di
Published: July 2011

The complex of human-like collagen (HLC) with copper (Ⅱ) was synthesized and analyzed in the present study, and the investigation was performed by UV-vis spectroscopy and FTIR spectroscopy. It can be concluded that there exists interaction between HLC and copper, and the complex is a new chemical compound different from free HLC from UV-vis spectra. In the complex of Cu, human-like collagen acts as the ligand, linking the copper ions via both groups of C=O and N-H.
Via Structure Optimized Design and Study of Copper Interconnect
Authors: Du Ming , Zhang Rui
Published: July 2011

Electromigration(EM) failure can be occurred in the via because of the high aspect ratio of Via and the high stress in the via. The theoretical and experimental study is developed in detail. The different via structures are designed and the simulation and accelerate test is operated. The result shows the current density and electric field in the via is decreased apparently and reliability is improved by use the structures, so it is considered of the practical means for improving the copper via interconnect reliability. Finally, two optimized via structures are advanced based on the result of experiments and simulations. The two structures are instructive for the design and manufacture.
Safety Analysis for Rock Slope Reinforced by Piles with Computer Aided Design Method
Authors: Wang Shu Yun , Xie Xiong Gang
Published: July 2011

The stabilization of slopes by placing passive piles is one of the innovative slope reinforcement techniques in recent years. There are numerous empirical and numerical methods for designing stabilizing piles. They can generally be classified into two different types: (1) pressure/displacement-based methods; (2) finite element/finite difference methods. However, seldom studies have been done on the stratified rock slope reinforced by piles, so in the present paper, the numerical simulation software FLAC3D is adopted to model the stratified rock slope, then the reinforced effect like deformation and stress of slope are studied, showing that if the pile is driven at the mid-bottom place of slope surface, the effect of controlling deformation of rock mass is the best. With increase of the length of pile, the maximum displacement of slope is decreased gradually.
Finite Element Simulation Analysis of Thin-Wall Parts Ultrasonic Vibration Turning Device
Authors: Zhao Yong Juan , Pan Yu Ti Tan , Zhao Shu Ying
Published: July 2011

Based on the thin-wall parts easily deformed difficult processing characteristics, design the vertical ultrasonic vibration turning device which is suitable for thin-wall parts precision machining utilizing the superiority of ultrasonic vibration turning processing.This device mainly includes piezoelectric transducer, composite horn, tool, tools folder body and the installation device part, carry on the finite element simulation for transducer, solid horn and the entire device system and compare with the resonance frequency of practical requirements, thus proving the reliability of the thin-wall parts ultrasonic vibration turning device we designed.
NC Ultrasonic Machining Efficiency: Neural Network-Based Modeling and Simulation
Authors: Zhong Gao Yan , Wang Yan Qing
Published: July 2011

To explore the impact of abrasive granularity, feed pressure and cutting feed speed on NC ultrasonic machining efficiency, a technological test was carried out, and based on the test results, back propagation (BP) neural network model was established and validated by simulation. The validation process showed that when relative error is less than ±10%, only two samples among 18 tested have larger errors. By the utilization of the BP network for training, correct fitting rate of machining efficiency target can be reached up to 88.9%. Our study indicates that (i) the output of the network is well fitted with the test data, (ii) the established model has good generalization ability to reflect the laws of NC ultrasonic machining process, and (iii) the model is suitable as a prediction tool for NC ultrasonic machining efficiency.
A Study on Carbon Electro-Conductive Filler for the Epoxy Conductive Coating
Authors: Li Bing , Li Yan Hong , Chen Wen Xing
Published: July 2011

To ensure the use of oil tank safely, it is necessary that the conductive coating was used in inner oil tank. This paper concentrates on a study of the electrical properties (surface resistance rate) of epoxy resins filled with different types of carbon pigments, such as colloid graphite, carbon black and mixture of colloid graphite/carbon black, as well as on the investigation of some mechanical properties, appearance and morphology .To produce a light grey and conductive coating, titanium oxide and carbon electro-conductive pigments were investigated in this article. The objective of the experiment therefore was to choose the optimal electro-conductive filler and determine the optimal mix ratio of colloid graphite/ carbon black and titanium oxide /colloid graphite and titanium oxide /mixable electro-conductive filler. From the experiment analysis, it was found that the optimized colloid graphite and carbon black mix ratio is 3:1; the optimized titanium oxide and colloid graphite mix ratio is 1:1; the optimized titanium oxide and mixable electro-conductive filler mix ratio is 8:1. In terms of resistance rate and color, we may arrive at the conclusion that 15μm colloid graphite as the optimized electro- conductive pigments and the optimal mix ratio of titanium oxide /colloid graphite is 1:1.
Original Industrial Application of two Numerical Models in Concasting Technology
Authors: Kavička František , Dobrovská Jana , Stránský Karel , Sekanina Bohumil , Stetina Josef , Masarik Milos
Published: July 2011

This paper deals with the causes of a transversal crack in a steel slab with an l300×l45 mm cross-section by means of results from two models. Samples were taken from and around the crack in order to analyze the concentration (chemical heterogeneity) of the selected elements. Simultaneously, the concentration of elements at the surface of the crack was measured after the crack was opened. The chemical heterogeneity of elements was analyzed by means of the JEOL JXA 8600/KEVEX analytical equipment. The measurement results were processed using mathematical statistics procedures. The results proved that there was an internal crack initiating immediately below the curve of the solid-state temperature and consecutively propagating.
Tool Errors Compensation in Precision and Ultra-Precision Milling Based on the Least-Square Method
Authors: Fan Kai Guo , Yang Jian Guo , Yang Li Yan
Published: July 2011

The CNC milling machine is extensively used in manufacturing of the die and the box-type parts. However, the tool errors, which caused by the cutting heat and the cutting force, seriously affect the machining accuracy of the machined parts. Furthermore, the tool errors are too complex to be calculated by the empirical formula. To solve this problem, a tool error compensation method is proposed in this paper. The least-square method is employed to structure the error model. A weighting coefficient is proposed to adapt the various working conditions. The macro program is used to realize the real-time error compensation. Using the tool error compensation method, the maximum tool error is reduced from 0.053 mm to 0.005 mm. The error is compensated by 90.5% compared with no compensation.
Study on the NOx Emission during the Combustion of Low-Quality Anthracite Coal in Supercritical Pressure W-Shaped Flame Boiler
Authors: Wang Wei Shu , Liu Jun , Pan Long Gang , Wei Hong , Zhang Hong Sheng , Li Shuai Shuai , Yan Guang
Published: July 2011

The combustion of pulverized coal in supercritical pressure W-shaped flame boiler is efficient.To decrease the formation of NOx in the furnace some reasonable measures are supposed to be taken to obtain low NOx combustion. In light of a 600MW supercritical pressure W-flame boiler, the combustion of low-quality anthracite coal and the formation of NO in the furnace are numerical simulated. The influence of concentration of pulverized coal, velocity of the primary air and the air distribution on the front and rear wall to the formation of NO is studied. The results indicate that NO emission at furnace exit can be effectively decreased by increasing the concentration of pulverized coal. Compared with the conventional concentration, NO emission can be decreased by 42%. The NO formation in the furnace can be controlled by selecting a reasonable primary air velocity on the front and rear arch, and there is a best primary air velocity. The study of supercritical W-flame boiler has great reference significance for the combustion adjustment and operation of large capacity W-shape flame boiler.
Optimaization of Single-Walled Carbon Nanotube for Adsorption of Methane
Authors: He Ke Rong
Published: July 2011

In this paper, methane adsorption in single-walled carbon nanotube (SWNT) has been simulated by using the grand canonical ensemble Monte Carlo (GCMC) method. Lennard-Jones (LJ) potential is used to represent the fluid-fluid interaction, Lennard-Jones potential and integral method are used to calculation of the potential between fluid molecules and carbon atoms, respectively. In the simulation, two methods of calculation of potential between fluid molecules and SWNT are compared. The potential calculated by the two methods are almost the same. Then the influence of diameter of SWNT on the usable capacity ratio (UCR) is analyzed, and the parameters of the SWNT which has the best adsorption performance at 300K is recommended under certain pressure.
A Software for Analyzing Structure of Amorphous Alloy
Authors: Zhang Hai Lin , Jiang Yu Bo , Tian Xue Lei
Published: July 2011

Structural analysis software for amorphous alloy has been developed. The structure factor, distribution function, the first coordination number, the first coordination radius, the correlation radius, the atomic number of cluster and the atomic average density of amorphous alloy can be gotten with this software. This software’s runtime stability and calculated accuracy was verified by its practical application. Structure of amorphous Zr41Ti14Ni10Cu12.5Be22.5 alloy was exactly analyzed using this software, which proved that the design of the software is precise and the calculation is exact.
Simulation Analysis of Splat Deposition in Plasma Spray Forming
Authors: Zhao Zi Yu , Xia Bi Bo , Zhang Su Zhi , Wang Li
Published: July 2011

Splat deposition is an important part influencing coating quality in plasma spray forming. Flatten behavior of a single Ni droplet falling on a smooth substrate is evaluated by numerical simulation of ANSYS software, this paper meanwhile researches a single Ni particle deposition in the surface of flattened Al2O3 sheet and thin Al particles, the impact factors of particles flattening and the mechanism of the interaction between particles are also studied. The results have benefit to improving the coating porosity and bond strength between particles.
Numerical Simulation of the Inner Flow Field of Hema-Type ATY Nozzle Based on Fluent
Authors: Liu Cui , Qu Yin Hu
Published: July 2011

The characteristics of air flow inside the inner channel of a Hema-type ATY(Air-Textured Yarn) nozzle were simulated based on the geometrical model of the inner channel built up usingPRO/E and the turbulent air-jet with a standard k-ε model simulated using Fluent．The simulation revealed that the ideal air in equivalent temperature came to channel while the flow pressure reached to the minimum．The results visually demonstrated the flow field of the inner channel of Hema-type ATY nozzle．And it could be a valuable reference for optimizing parameter on the Hema-type ATY nozzle.
Ultrasonic Polishing of Electric Discharge Machined Surface Using Al2O3 Suspension
Authors: Lee Won Sik , Seo Jung Sik , Ko Se Hyun , Jang Jin Man , Cha Bermha , Son Seong Ho
Published: July 2011

The aim of this work is to investigate the possibility of improvement of surface roughness in the wire-EDMed sample by usinig ultrasonic wave and abrasive particle suspension. For this study, two-type ultrasonic polishing methods were used. Removal of the white layers on surface of EDMed sample depended largely on the movement of the suspended particles : the white layers are removed by the impact of free moving particles due to ultrasonic wave, so-called micro chipping mechanism. Even though the surface roughness was improved very slowly, 3-dimensional fine polishing was achieved in wire-EDMed micro PIM molds. These results indicated that micro polishing by ultrasonic wave using suspension is applicable to improvement of surface roughness of micro parts with 3-dimensional complex shape.
Simulation for Handing and Stability of Vehicle Based on SimulationX
Authors: Cao Yong Xin , Liu Yan Fang , Xu Xiang Yang , Yang Yang
Published: July 2011

To build a dynamic vehicle model is the most important work in the field of digital virtual prototyping technology for studying on its handing and stability. A 54 degrees of freedom multi-body vehicle model with tire, suspension and steering was established in SimulationX software. Time domain response under steering wheel step input and frequency response under steering wheel sinusoidal input were obtained, the changing trend of indicators with different speeds was presented, the handing and stability of vehicle model was evaluated, also the impact of caster angle and kingpin inclination to handing and stability was analyzed. The simulation results were consistent with theoretical analysis and actual situation.
Three-Dimensional Finite Element Analysis of Polymer Coextrusion through Cylindrical Channel
Authors: Zhang Min , Huang Chuan Zhen , Sun Sheng , Jia Yu Xi , Liang Tian Jiang
Published: July 2011

The eccentricity coextrusion flow of polymer melt was analyzed based on finite element simulations. Such simulated results as the fields of flow velocity, pressure and shear stress were obtained. Through the analysis of the results, the mechanism of the column interface forming in the axis-symmetry coextrusion flow path was obtained. For the coextrusion flow, if the low viscosity polymer flows near the die wall, the flow would be steady. Whereas, if the polymer with low viscosity is in the core and the high viscosity polymer at the outer region, Which is disadvantage in terms of energy, and the instability flow would occur. This is also accord with the least energy consume theory.
Measurement and Analysis on Tensile Strength and Crystallinity of Vibrating Extruded High-Density Polyethylene (HDPE) Sheet
Authors: Shi Bao Shan , Qin Xue Mei , Li Bing
Published: July 2011

By the apparatus of differential scanning calorimetry (DSC), scanning electron microcopy (SEM) and wide angle X-ray diffraction (WAXD), The effect of vibration on the microstructure and mechanical properties of high-density polyethylene (HDPE) sheets, obtained through vibration plasticating extruder in low temperature, were measured and analysed. The result show that the tensile strength was much improved under the reciprocating axial vibration in low temperature. The phenomenon indicate that the vibration extrudate in low temperature has higher crystallinity, perfect crystallite, and strong inter-spherulite ties, which account for enhancement of the mechanical properties of sheets, compared to conventional static extrusion.
The Analysis to the Forming Process of Welded Pipe by Non-Linear Finite Element Method
Authors: Ye Jin Duo , Li Zhe , Xi Yu Ting
Published: July 2011

Understanding the mechanism of the forming of the welded pipe may help the engineer to design the shape of forming rollers and forming technology. It is hard to study the forming process of the welded pipe by both the method of experiment and numerical modeling because of too much nonlinear factors included in the forming process such as elastic-plastic large deformation and non linear contact. Although many research works have been conducted in this field by the method of experiment or numerical modeling, but few of the works deal with the whole forming process of the welded pipe. The main difficulties in the numerical modeling are of huge computational labor time, witch has been over the ability of the hardware and software of the computer. The whole process of roll forming of welded pipe has been simulated by nonlinear finite element method with ANSYS and LS-DYNA solver, the distribution of both stresses and strains have been got successfully. Mapping meshes and the rigid models for rollers have been used in the analysis in order to decrease the number of the elements. Numerical results and parameter study have shown that the forming rollers of both the level and vertical are the key factors to the forming process. It is believe that the method used in the paper can also be used to study the forming process of both cage roll forming and flexible forming.
Investigation on the Formability of Tube in Hydroforming with Radical Crushing under Simple Loading Paths
Authors: Lei Pan , Yang Lian Fa , Zhang Yu Xian
Published: July 2011

Tube hydroforming with radial crushing (THFRC) process is particularly applicable to the tube which is difficult to shape due to lack of axial feeding. In this paper, the formability of the circular tube expanded into a triangle cross-section under the simple loading paths is explored by using the numerical simulation. The effect of the forming mode and the loading paths on bulged profile, wall-thickness distribution and the potential fracture location of the bulged tube are analyzed. The results showed that constraint conditions at tube ends have small influence on the bulged profile and wall-thickness distribution. Moreover, the larger the peak value of the internal pressure is, the better material filling ability and higher accurate the tube bulged profile are. Furthermore, the higher forming accuracy, the better material filling ability and wall-thickness distribution are gained in THFRC than those in free hydro-bulging (FHB) process, and they can be obtained under constant than linear pressure loading paths. Finally, the potential fracture location of the bulged tube in THFRC process is quite different from that in FHB process.
Adaptive Learning of Bending Force Presetting Model in a Six-High Cold Rolling Mill
Authors: Bai Jin Lan , Wang Jun Sheng
Published: July 2011

In this paper, adaptive learning method of bending force presetting model in a six-high cold rolling mill is introduced. Adaptive learning coefficient of bending force presetting model is calculated by contrast between measured and model calculated actual bending force, then exponential method is used to modify the adaptive learning coefficient to improve the precision of the bending force presetting model. While calculating model calculated actual bending force, Legendre polynomials are used to convert measured flatness data to quadratic and quartic flatness coefficient, then regulating quantity on the quadratic flatness coefficient of intermediate roll bending force and work roll bending force is determined based on their regulate capability. Practical application shows that precision of the bending force presetting model has improved significantly by adaptive learning.
Conformation and Activity of Sol-Gels Encapsulated Cross-Linked Enzyme Aggregates of Lipase from Burkholderia cepacia
Authors: Liu Yun , Guo Yu Ling , Chen Da Wei , Peng Cheng , Yan Yun Jun
Published: July 2011

Cross-linked enzyme aggregates (CLEAs) of lipase from Burkholderia cepacia (BCL) were explored using different precipitants and different amount of glutaraldehyde as cross-linkers. The ‘fresh’ and ‘mature’ CLEAs-BCL was successfully encapsulated with sol-gel support. The latter showed the highest specific enzyme activity, which was 1.7 and 13.2-fold over CLEAs-BCL before encapsulation with sol-gel and free BCL, respectively. It performed high transesterification activity with the biodiesel yield of 88.5%. The ‘mature’ CLEAs-BCL presented high stability in the ranges of temperature (30-70 ºС) and pH (pH = 5-10). Scanning electron microscopy (SEM) and circular dichroism (CD) studies showed that the morph secondary structure of ‘fresh’ and ‘mature’ CLEAs-BCL was variant to some extent, which may be responsible for the catalytic activity variance.
Hot Deformation Behavior of Zn-8Cu-0.3Ti Alloy and its Flow Stress Model
Authors: Xu Xiao Qing , Li De Fu , Guo Sheng Li , Wu Xiao Ping
Published: July 2011

The hot deformation behavior of the Zn-8Cu-0.3Ti alloy was researched by compression test on Gleeble-3500 thermo-simulation machine. The results indicated that the flow stress increased rapidly with the increase of the strain at the initial stage, however, the flow stress decreased and become steady when the strain exceed a certain value. The steady stress and peak stress increased with the decrease of the deformation temperature and the increase of the strain rate. The variation regulation of the deformation activation energy and stress exponent with the strain was established through the regression method. The hot deformation constitutive relationship was also established. Comparing with the experimental results, it was proved that the model reflected the real deformation feature of Zn-8Cu-0.3Ti zinc alloy.
Hot Deformation Behavior and Microstructure Evolution of GH625 Superalloy Tube during Extrusion Process
Authors: Guo Qing Miao , Li De Fu , Guo Sheng Li , Xie Guo Ling
Published: July 2011

Flow behavior and microstructures of GH625 superalloy were investigated by hot compression tests. Then the GH625 superalloy tube was hot extruded according to the hot deformation behavior, and the microstructures of different position of extruded tube was also analyzed. The results show that the actual deformation temperature of the specimen deformed at a strain rate of 10.0s-1 is higher than the preset temperature, resulting in a deformation thermal effect. Thus, the microstructure evolution of GH625 superalloy is controlled both by the strain rate and deformation temperature. It is also found that the GH625 superalloy tube can be successfully fabricated with a stable extrusion speed of 40 mm·s-1, extrusion ratio of 4.1 and preheating temperature of 1200°C. The microstructure of extruded tube was obviously fined due to the occurrence of dynamic recrystallization(DRX). Different degrees of DRX were observed in outer wall, center and inner wall of the tube, which is similar to that in the head, middle and tail of the tube. An extruded tube containing fully DRX grains can be obtained by cutting the head and tail of the tube, and machining a small amount of the inner wall.
Study on the Structure Improvement of Slanted-Guide-Pillar Core-Pulling Mechanism in Die-Casting Die
Authors: Zhang Hong Feng , Ma Shi Bang
Published: July 2011

The slanted-guide-pillar core-pulling mechanism is the most commonly used side core-pulling mechanism in die-casting die. But when filling the die with pressure, aluminum leak frequently happens between lower motion-stopping surface of sliding block and side surface of moving die insert, since the clearance is bigger between side core and core hole. In many improved approaches, changing the lower motion-stopping surface of sliding block into upper motion-stopping surface of it or reducing the lower motion-stopping surface area is the simplest and reliable measure. The sliding block’s setback which occurs in die-casting process can be eliminated effectively and the workload of maintaining die can be reduced by this measure.
Back-Stepping Design Research of Spline Die Based on Cold-Rolling Forming
Authors: Wang Zhi Kui , Zhu Qing Hui
Published: July 2011

The author introduces the method and steps of determining key parameters of spline cold-rolling die using back-stepping design method. To verify the feasibility of the back-stepping design method in theory, the author made forming simulation and experiment with cold-rolling tooth-entwisted spline designed, analyzing the relationship between die design parameters and spline forming precision and giving correction way. Finally, the related factors influencing the forming precision of spline are introduced and the practical significance in machine-building industry of the back-stepping design method is emphasized.
Defect Recovery and Control in Heavy Forgings by Two Times Upsetting and Stretching Process
Authors: Su Juan Hua , Chen Yan Wei , Chen Yun Yun , Shi Yu Lin
Published: July 2011

In practical production, the heavy forgings of the largest diameter 1225 mm larger than its length 905 mm are unqualified for supersonic inspection. By means of acid-eroding, scanning electron microscopy and energy spectrum analysis on defects, it is shown that the defects are originated from inclusions made up of Al2O3, Fe2O3and a little CaO. In order to improve forging quality, the controlling mechanism of defects is analyzed, and forging process of two times upsetting and stretching process is researched to eliminate the cracks originated from inclusions. The result shows that the inclusions in forgings can be controlled and the inner cracks recovered effectively by two times upsetting and stretching process. All of the forgings meet the supersonic standard which indicates that this process is better fit for heavy forgings with largest diameter larger than its length.
Fabrication of SiCp/Cu Composite by Powder Injection Molding
Authors: Yang Jian Ming , Li Hua Qiang , Chen Hua , He Yi Qiang , Feng Li Chao
Published: July 2011

A SiCp/Cu composite with excellent performance is prepared by using the advanced powder injection molding technology. The microhardness and tensile strength of the composite are detected, and the surface microstructure and the tensile fractures are observed. The results show that SiC particles are uniformly distributed in Cu matrix and excellently bonded with the Cu matrix. With the increase of the SiC content, the microhardness of the composite is increased while the tensile strength is increased first and then decreased. A crackle source of the composite for tensile fracture mainly includes two kinds: cracking of the Cu matrix in vicinity of the SiC particles and debonding of an interface of the SiC particles and the Cu matrix.
Microstructure Analysis of FeS Layer as Solid Lubrication Composite Coating Produced by Low-Temperature Ion Sulfurization
Authors: Qiao Yu Lin , Zang Yan , Yang Shan Lin , Hu Chun Hua
Published: July 2011

The ferrous sulfide (FeS) solid lubrication composite layer was prepared on the surface of CrMoCu alloy cast iron that treated by ion Nitrocarburizing, with low-temperature ion sulfurizing technique. By morphology and composition analysis, it is shown that the FeS layer has a micro-nano-hole structure, formed by nanometer sulfide particles, and the composite layer surface is mainly FeS. Also, there are a cross area and a diffusion area between the ion sulfide layer and the ion nitrocarburizing layer.
Technique of Laser-TIG Hybrid T-Shape Joint Welding of Titanium Alloy
Authors: Wang Min , Jiang Mei Ling , Wei Qiang , Gu Kan Feng
Published: July 2011

Against the T-joint connection problem, the CO2 laser and TIG arc hybrid welding Experiment Platform is set up. The implemented T-joint titanium alloy connection test adopts a novel fashion that while welding the upside of the sheet the bilateral back formed well. The preferred solution is presented based on studies such as arrangement of heat source, wire feeding, shielding gas selection and gap adaptability. The results reveal that the technology provides a new efficient method for the T-joint titanium alloy connection.
Microstructures and Properties of FSW Joints of AZ31B Mg Alloy
Authors: Yu Si Rong , Chen Xian Jun
Published: July 2011

The extruded AZ31B Mg alloy sheet was welded with friction stir welding. The microstructures and mechanical properties of the welded joint were investigated. The results show that the grains in the weld nugget zone were small, uniform and equiaxed. The grains in thermo-mechanical affected zone were stretched and relatively small, but were not as small and uniform as those in the weld nugget zone. The grains in the heat-affected zone were relatively coarse. The fracture of the welded joint occurred mainly in the heat affected zone. The tensile strength of the welded joints was up to 257.4 MPa and was 87.9% of the base material strength. The microhardness in the weld nugget zone was higher. The microhardness in the thermo-mechanical affected zone and heat affected zone were lower than that in the weld nugget zone. The microhardness in the weld nugget zone increased from the upper surface to the bottom.
Electrode Lifetime in Spot Welding Galvanized Sheet with Insert Material
Authors: Shuai Ge Wang , Fang Ping , Guo Zheng Hua
Published: July 2011

The effect of copper strips as an insert material on electrode failure has been studied during spot welding of galvanized sheets. The results showed that an extended electrode lifetime was obtained due to the use of copper strips between electrode and workpiece which prevented electrode from alloying with molten zinc and lowered the temperature of electrode tip. In addition, the presence of inserted copper strip increased the resistance of welding system, thus generated much more heat to form larger nugget The electrode degradation mechanism was basically caused by deformation at electrode tip and wear.
Analysis on the Residual Stresses in the Aluminum Alloy Friction Stir Welded Joints
Authors: Cao Li Jie
Published: July 2011

The residual stress fields can have strong influences on the integrity and performance of friction stir welded aluminum alloy structure, comprehensive insight into the residual stress distribution is the key to the Friction stir welding (FSW) engineering application for a wide range of materials and thicknesses improving the weld strength and fatigue life. In this paper, the current state of the residual stresses in the FSW aluminum alloy joints is reviewed, The focus is on recent advances of experimental research, the results of numerical simulation analysis, and the effects of the technological parameters(welding speed, rotational speed, shoulder geometry et al.) on residual stress fields was evaluated. In the end, The controlling technique of residual stresses from published literatures is summarized.
Influence of Hydrogen on the Plasmas Nitriding Process of 35CrMo Steel
Authors: Zhong Li , Han Xi
Published: July 2011

The mechanism of the formation of active nitrogen atoms and the function of hydrogen molecules for the dissociation of the mixture of nitrogen and hydrogen in the plasma nitriding process are discussed in this paper. The results show that the nitrided case thickness of nitrided samples become thinner and the surface hardness decreases with the increase of cathode voltage. Active nitrogen atoms mainly result from non-elastic collision between positive ions H2+ and neutral particles N2 for N2-H2 mixture plasma nitriding at 550V cathode voltage, the volume percent of e-Fe3N and the superficial nitrogen concentration of plasma nitrided case decrease with the increase of the mixture ratio of N2/H2. However, active nitrogen atoms mainly result from non-elastic collision between energetic positive ions H2+, N2+and neutral particles N2 for N2-H2 mixture plasma nitriding at 650V cathode voltage. The existence of a few of nitrogen molecules makes critical energy of positive ions H2+ dissociating neutral N2 molecules drop to 26.06eV and the cathode voltage threshold value become 490V.
A Novel Electron Paramagnetic Resonance Phenomenon in a Barium Stronium Titanate Ceramic
Authors: Lu Da Yong , Sun Xiu Yun
Published: July 2011

The electron paramagnetic resonance (EPR) technique was employed to investigate the point defects in barium strontium titanate ceramics. All samples showed a strong EPR signal with g = 2.000, which was indexed as intrinsic Ti-vacancy defects. In (Ba0.85Sr0.15)TiO3ceramic, which showed a tetragonal symmetry and consisted of the crystallites with average size of ~ 220 nm, a novel EPR powder spectrum was observed - the g-factor of theg= 2.000 signal evolved into ag-tensor, and the two weak signals withg3= ~ 2.6 andg1= ~ 1.6 gradually shifted toward the g2 = 2.000 signal and approached to each other with increasing temperature.
Control of Nitrogen in Al-Killed Steel by Converter Flow
Authors: Wang Shuo Ming , Zhang Jin Hong , Liu Hao Ming
Published: July 2011

This paper analyses and studies control of nitrogen on Al- killed steel using the methods of production experiment in the flow of molten iron pretreatment - 180t converter - LF refining – continuous caster. Results show that adding aluminum final deoxidization should be divided into two steps: Firstly, putting some aluminum into molten steel after adding alloy in the process of tapping of molten steel, making the [O] reduce to 6 ~ 7ppm. Secondly, adding aluminum wire in LF-refining making [O] and [N] reach the required values. LF-refining should try to shorten operating time and original mission ought to be finished ahead. Desulfurization should be completed in the flow of molten iron pretreatment and the tapping of molten steel. Process of removal inclusions should be accomplished by adding slag during tapping of molten steel and blowing-mixing. LF-refining has scarcely any slagging task, it only needs to complete adjustment ingredient task. Alloy and carburant which contains extremely low nitrogen should be choosed, so that nitrogen in molten steel can be steadily controled below 30ppm.
New Digital Method of Reverse Engineering about Free from Surface
Authors: He Xue Ming , Xue Ying , Li Cheng Gang , Hua Chen Liang , Lu Yi
Published: July 2011

In this paper, it is proposed a new method of free-from surface’s reverse engineering, making data acquisition and surface reconstruction form closed loop system, solving no feedback problems in the measuring and modeling process, shortening the time of the whole reverse engineering, improving the quality of reconstructed models. The core of this paper is used the CMM adaptive measuring method and non-uniform b-spline surface reconstruction method, integrating the free-from surface measuring and modeling in a closed loop system, realizing the CMM real-time online measurement and reconstructed surface real-time update.
Self-Assemble Behavior of Amphiphilic Diblock Copolymer of Methoxy Poly (Ethylene Glycol)/Polyester
Authors: Zhou Hao , Liang Qing Hong , Shi Xiang Ke , Lu Li Hua , Zhang Li Qun , Yue Dong Mei
Published: July 2011

Amphiphilic diblock copolymers based on methoxy polyethylene glycol (MePEG), 1, 6-hexanediol and maleic anhydride with different molar composition were synthesized by solution polycondensation. Self-assemble behavior of amphiphilic diblock copolymer in different solvents by dialyzing technique was discussed. The micelle morphologhy was observed by TEM. It was found that well core-shell MePEG1900/Polyester 2162 copolymer nanoparticles can be formed by self-assemble in acetone solution. In addition, the size of nanospheres measured using dynamic light scattering exhibited a narrow monodisphere size distribution and an average diameter in the ranger of less than 200nm.
Experiment on Treating the Dying Wastewater with Blast-Furnace Ash and Fenton Reagent
Authors: He Yan Qing
Published: July 2011

The dyeing wastewater was treated via oxidation, coagulation and adsorption with Fenton reagent and blast-furnace ash. The removal efficiencies of colority and COD reached 90% and over 70% respectively.The proper process conditions were deter mined as follows: the pH of wastewater was 6, the dose of H2O2was 40mL/L, the dose of FeSO4was 0.3moL/L, and the dose of ash was 40g/L, and the retention time was 20 min.
Characterization of Electrochemically Synthesized Pani on Graphite Electrode Use EIS
Authors: Zhou Qiong , Su Xiao Mei , Zhang Hong , Weng Yong Ji
Published: July 2011

Polyaniline (Pani) on graphite electrode was synthesized electrochemically under galvanostatic condition at current density of 2.0 mA/cm2 from aqueous solution of 1.0 mol/L HCl and 0.25 mol/L aniline monomer. The Electrochemical Impedance Spectroscopy investigation of Pani was carried out at different stages of polymers oxidation. In the potential range 0.2V~0.7 V vs SCE, with the increase of test potential the membrane resistance decreased rapidly, and Faraday process at the polymer/solution interface weakened. When the test potential in range of -0.8V~0.2V or 0.7V~0.8V, the film has a higher membrane resistance, and lower ionic charge transfer resistance, which indicated that the ion exchange for the charge compensation at the polymer/electrolyte interface is much easier. And anticorrosion properties of Pani coating of different oxidations was investigated by salt spray test. The final visual observations of the tested coatings are in agree with the results of electrochemical impedance spectroscopy.
Study on Efficiency-Reinforcement Design Methods for Elastomeric Hydraulic Reciprocating Sealing
Authors: Zhang Fu Ying , Zhang Hong Chao , Zheng Hui
Published: July 2011

The high efficient, high reliability and energy-saving development of modern machinery equipments challenges the higher request for hydraulic sealing technology. However, current seal designer usually operates on the basis of his experience and skill, without systemic design theories and methods as guides. In this paper, according to the work principle of elastomeric hydraulic reciprocating sealing, the seal efficiency reinforcement design theory such as seal efficiency-reinforcement design rules and the seal failure criterion are proposed based on the numerable model and finite element analysis methods. This theory can offer theorical methods guider for seal design, so as to satisfy modern machinery equipments request for higher effciency and environment protest.