bluuebunny/crossref_metadata_2025 huggingface dataset:
Analysis of Collisions of Vehicle and Concrete Barrier on Rural Highways
Authors: Sun Yu Juan , Rong Jian , Tai Yong Gang
Published: December 2011

A concrete barrier used on rural highways of China was proposed. The crashworthiness of the concrete barrier was analyzed using the non-linear explicit dynamics FE code LS-DYNA. The finite element models of car, bus and concrete barrier were developed and validated using experimental results. These models can be used to simulate the dynamic collision process and evaluate the performance of the road safety barrier on rural highways. The nonlinear performance of materials as well as the boundary conditions was considered. The results show that the concrete barrier could contain and redirect the car and bus in the collision.
Aircraft Three-Proof Index System Establishment and Evaluation Method Study
Authors: Zhang Tai Feng , Yang Xiao Hua , Zhao Wei Yi , Zhang Shi Lu
Published: December 2011

In view of comprehensive evaluation of the Three-Proof performance for modern aircraft, and based on the damage mechanism of heat and humidity, salt air, and mildew, the comprehensive evaluation index system is established. The weight of each evaluation index is determined with mathematical statistics method and the operations research theory. The comprehensive evaluation model for aircraft Three-Proof performance under the influence of multi-factors is established by using the technology of multi-index comprehensive evaluation synthesis. Through normalized and standardized processing of the data, the Three-Proof performance comprehensive evaluation was carried out on several kinds of typical aircraft in our country. The evaluation result is reasonable, which confirms the credibility of the model as well as the method.
Study on Speciation of Cr in Cement
Authors: Bai Rui Ying , Yu Qi Jun , Feng Xiao Xin
Published: December 2011

A modified Tessier sequential extraction procedure was employed to investigate the speciation of Cr in cement products. The amount of Cr in extracting solution was determined by atomic absorption spectrophotometer and extraction residue was analyzed based on the results of XRD, SEM and EDS. The distribution of Cr in cement was discussed also. Cr existing as species exchangeable or bound to carbonates increases with curing age gradually.
Study on Hot Dip and Coating Structure of 55% Al-Zn Alloy Coated Steel
Authors: Leng Yan Hong , Feng Yun Li , Song Meng
Published: December 2011

Hot dip galvanizing treatments of Galvalume were studied by using methods of Gleeble thermal simulation experiment and optical microscopy(OM), scanning electronic microscopy (SEM), X-ray energy dispersive analysis(EDAX), X-ray diffraction(XRD) and so on. Meanwhile, surface morphology, microstructure, phases and the respective compositions of Al-Zn alloy coating plate were investigated, the formation of hot dipped 55％Al-Zn alloy coating were analyzed. The results show that to get better coated surface, in-zinc pot temperature should be controlled in the range of 590~610°C, and height of air-knife nozzle should be kept in the range of 150~200mm. Surface layer of 55％Al-Zn alloy coating is covered by Al-Zn alloy, the intermediate alloy layer is consisted of binary and ternary compounds, such as θ phase (FeAl3), Al0.3Fe3Si0.7and Al3.21Si0.47.
Study on Growth and Crack of Yb:YAG Laser Crystal
Authors: Zhang Xue Jian , Li Chun , Zhang Ying , Lin Hai , Gu Liang , Liu Jing He , Zou Guang Tian
Published: December 2011

The 5at.% Yb3+-doped YAG crystal was grown by the Czochraski method, and the crystal growth process was investigated. the optimal process parameters were determined as follows: The crystal growing rate for Shoulder growth and equal-diameter growth were 0.8mm/h and 1mm/h, respectively. The optimal Rotation speed of this crystal was 15rad/min, and the axial temperature gradient was 0.01−0.05°C/mm. The impact factors to crystal growth were analyzed theoretically, such as growth rate, rotation speed, thermal effect and crystal size.
Development Research of Failure Theories for Thick Composite Laminates
Authors: Zhu Xian Fei , Feng Yun Wen , Feng Yuan Sheng
Published: December 2011

Current failure theories for predicting failure in composite laminates have been studied and compared in a systematic and detailed manner, to identify the strengths and weaknesses of each theory, together with a ranking of the overall effectiveness of each theory. Careful reading of this analysis and study of figures provided will inform the reader when selecting an appropriate failure theory for use in a given design situation. It will also provide a qualitative assessment of the likely accuracy and reliability of the prediction in a given circumstance.
Synthesis and Properties of Epoxy Resin/Graphite Composites via In Situ Polymerization
Authors: Lu Xue Feng , La Pei Qing , Guo Xin , Wei Yu Peng
Published: December 2011

Synthesis and properties of epoxy resin/graphite composites via in situ condensation polymerization of monomers in the presence of graphite particles were investigated. The results showed graphite particles were well dispersed in the epoxy resin matrix. Shore hardness and bending strength varied with the amount of graphite, and they were all improved greatly by an optimal content of 17.44 % (mass fraction). The bending strength was 22.4MPa and Shore hardness was 9.8 HD. A plastic deformation can be seen in the composite with the range of strain 0.6-0.8%. The fitted yield strength is about 20MPa.
Adhesion of TiC/Fe Cermet Interface with C Vacancy: A First-Principles Study
Authors: Zou Zheng Guang , Liu Kai , Shen Yu Fang , Xiao Zhi Gang , Long Fei , Wu Yi
Published: December 2011

This work focus on the effects of C vacancy on wetting of Fe to TiC/Fe at the cermet interfaces. We do the whole work using the first-principles density functional theories. The ideal work of adhesion of the pure interface is not big enough, comparing with the expeimental value. Our calculations suggest that the C vacancy at the interface is a very important factor for interface banding of TiC/Fe cermet composite. An adequate quantities of C vacancies at the interface can improve the wetting of TiC/Fe interfaces.
Preparation and Performance of a Novel Intumescent Flame Retardant
Authors: Zhang Xiang , Zhang Fan
Published: December 2011

A novel phosphor-nitrogen intumescent flame retardant was prepared by dry method (without adding any solvent) using H3PO4, P2O5, pentaerythritol and melamine as raw materials. IR analysis found that the synthetic flame retardants had the P=O and P-O-C double-ring structures, the same to phosphate ester melamine salts. The reaction temperature, time and the ratio of raw materials had significant effect on the esterification reaction. The esterification reaction temperature should be controlled between 120°C and 130°C, and the reaction time should be 2.5 hours. The conversion rate of esterification could be improved by adding P2O5 to the reaction, and preferential mole rate between H3PO4 and P2O5 should be 2:1. Thermogravimetric analysis showed that the starting decomposition temperature of the flame retardant was 190°C, and at 700°C, the residual char rate was about 30%. The expansion ratio of the flame retardant after heated was about 30 to 50 times, SEM analysis found that the exteral surface of the expansion char layer was continuous and smooth, and the interior of the expansion char layer was uniformly porous structures, and the aperture size was about 150-200 μm, such porous structures could provide better adiabatic effect.
Low Temperature Preparation of ZnIn2S4 by Hydrothermal Method and its Visible Light Photocatalytic Property
Authors: Guo Ming Xing , Yin Shu Hui , Han Yi Xuan , Wang Chang Yun
Published: December 2011

In this paper, ZnIn2S4 crystals are synthesized in one step at 45°C~65°C by using hydrothermal method and the sample is identified via such technologies as scanning electron microscope, x ray diffraction and UV-visible spectrum. The results show that: hexagonal structured crystals can be prepared at the above-mentioned synthetic temperature; as to the sample obtained at 65°C, its average grain size is about 20~50um and it has a petal-like surface. Taking this ZnIn2S4 microsphere as a catalyst to catalyze the degradation of methyl orange under visible light, the degradation rate of the methyl orange after 2h illumination is above 97% and 100% after 2.5h. This indicates relatively high activity of degrading methyl orange.
Universal Serial Protocol Grammar Analysis Model
Authors: He Bao Feng , Li Rui Min
Published: December 2011

Serial communication protocol doesn’t have a uniform format due to the differences of its hardware. Thus it’s inconvenience for the test and program design. Through the grammar analysis of the mainstream equipmen Serial protocol, found out a universal protocol format, and also it designed a universal protocol testing tool. It can be use widely for testing many serial communication protocol.
Study on the Filling Particle for Foam Ferrous Metalmaking Needed
Authors: Luo Xiao Ping , Kang Li , Ren Jian Fu
Published: December 2011

A novel manufacturing and dissolving technology of filling particle for making foam ferrous metal by infiltration process has been developed. The filling particles were fabricated with a mixing method, and were bonded together through a heat treatment to form a sphere assembly in a mold.The results showed that the size of the filling particles 3-5mm and the concentration 20% of the hydrofluoric acid can meet the need .Based on the orthogonal experiments, shaping forming process and ratio of raw materials and solvent ae also investigated in this paper. The result show that 40% sodium silicate, 90% silica sand concentration and 1% of adhesive ratio have better foam ferrous metal. The thermodynamics and kinetics analyses show that the filling particle can be dissolved in the hydrofluoric acid solvent and good foam ferrous metal was obtained.
Nano Materials Used in Industrial Design
Authors: Wu Fen , Hu Wei Ping
Published: December 2011

This article introduces Nano materials exploitation and application, especially about achievements of Nano materials in industrial design field and forecast for its developing trend and market prospect in the future.
The Influence of Debonding Interface on the Effective Mechanical Properties for Nano-Composites
Authors: Luo Dong Mei , Zhou Ying Long , Zhu Wen Liang , Wang Wen Xue
Published: December 2011

Combining the contact elements into the two-scale homogenization method, the effective mechanical properties of nano-composites with a debonding interface are analyzed. A periodic microscopic representative volume element (RVE) is modeled by using a four-phase composite composed of matrix, nano-tube, bonded, and debonding interfaces. The initial stress and coulomb's friction are considered within debonding interface, which is applied to transfer the shear stress produced by the relative slip between nano-tube and matrix, and a simple elastic–plastic constitutive model is established to study the effective mechanical properties of nano-composites. The predicted results show a strong non-linear dependence of the effective mechanical properties on the elastic modulus, volume fraction, debonding length and the ratio of length with thickness of interface.
Analysis of Failure Mechanism for a Diversion Ditch in Lake Beach
Authors: Wang Xiao Yan , Duan Shi Wei , Xu Xian’e , Wang Hao Liang
Published: December 2011

The paper discusses the contributing factors of dike failure occurred during construction of the diversion ditch. It is concluded that composition of ground and effect of the groundwater are physical element of slide, soil from ditch excavation placed on the top of flanking slopes for embankment and stress-relief at the foot of flanking slope by excavation are induced factors.
GaN-Based LEDs on Nano-Patterned Sapphire Substrates
Authors: Zhang Jing , Sakai Shiro
Published: December 2011

We have successfully fabricated light emitting diodes (LEDs) based on patterned sapphire substrates (PSSs) fabricated by employing nanoimprint lithography (NIL) technique. The nano-patterns were designed as regular triangles consisting of columns, whose diameters and pitches were 100, 150, 200, 250 nm and 200, 300, 400, 500 nm, respectively. 412 nm wavelength LEDs grown by metal organic chemical vapor deposition (MOCVD) method were also demonstrated. The NIL technique and nano-etching by employing RIE were demonstrated in details. The qualities of all LEDs based on PSSs are superior compared with that non-patterned sapphire substrate LED. The experimental results showed that the light output power was increased by using the PSS structure. At a driving current of 20 mA, the light output powers of LEDs based on PSSs with 200, 300, 400 and 500 nm pitches are enhanced by 59%, 79%, 42% and 48%, compared with the conventional LEDs. These results provide promising potential to increase output powers of commercial light-emitting devices.
Kinematics Simulation of Industrial Robot Based on MATLAB
Authors: Cai Han Ming , Xing Ting Ting
Published: December 2011

In this paper, we discussed the kinematics simulation of a six DOF (degree of freedom) industrial robot, modeling the robot with PRO/E. D-H coordinate transformation method is used to establish coordinates of robot kinematics mathematical model and the target matrix. The powerful symbolic computation of MATLAB functions is used to analyze the equation, and the inverse kinematics solution is obtained. The joint trajectory of the robot in the implementation of task and workspace are worked out through the forward kinematics solution.
A Study of Divergence on still Point Charge and Moving Point Charge in the Vacuum Passive Space
Authors: Zheng Guo Tai , Qin Jiu Ying
Published: December 2011

The divergence of still point charge is zero in the vacuum passive space, but the divergence of moving point charge is not zero. In order to make the divergence of moving point charge in the vacuum passive space being zero, we must choose the coordinate in which moving point charge has the same velocity with the coordinate as a reference system.
Extraction Feature of Gas Flucturation of Guideway System Based on the Wavelet Transform
Authors: Chen Dong Ju , Fan Jin Wei , Li Hai Yong , Zhang Fei Hu
Published: December 2011

A new method for extracting spectrum feature of gas flucturation of aerostatic guideway is proposed. The flatness error of workpiece surface includes much errors information, and the information contains high frequency signal and low frequency signal, for these errors information, a new identification method of turning errors of workpiece based on the wavelet transform and power spectral density analysis is proposed. According to the focal variation character of wavelet and the energy value of power spectral density analysis, the feature of gas flucturation of aerostatic guideway from the measured flatness error of workpiece is extracted and identified.
Performance Study of ZrO2-Al2TiO5 Composite Prepared by Solid Phase and Coprecipitation Method
Authors: Zhang Li Fang , Dong Cui Zhi , Zhang Hui Fang , Bu Jing Long
Published: December 2011

ZrO2-Al2TiO5 composites were finally prepared with synthetic powders by coprecipitation or solid method phase.we compared with their properties. The results show that the sintering properties and thermal shock resistance of ZrO2-Al2TiO5 composites prepared by coprecipitation method are superior to solid phase method.
Preparation and Characterization of SnO2/TiO2 Composite with Low Infrared Emissivity
Authors: Wang You Jun , Shao Jin Ping , Deng An Zhong , Li Dong
Published: December 2011

SnO2/TiO2composite material was prepared by use of microwave deposition method, on basis of tetrabutyl titanate(C16H36O4Ti) and tin tetrachloride(SnCl4) were used as source material and carbamide (CO(NH2)2) as precipitator. The characteristics of composite material were investigated by means of X-ray diffraction (XRD), scanning electron microscope(SEM) and Fourier transform infrared(FTIR). The result showed that optimization mol ratio of carbamide and metal elementary( Sn & Ti) was 2:1. SnO2adulteration counterworked TiO2crystal transformation and restrained rutile nucleation. Anatase TiO2grew up easily. SnO2content had been influence on composite material average emissivity at 8~14 waveband. Mix proportion of composite material was achieved which emissivity was 0.3185.
The Design Study of New Insulation Board Synchronous Fixed-Length Cutting System
Authors: Sun Jun , Mi Song , Zhu Hong , Xu Tong
Published: December 2011

Aiming to solve the plate-cutting difficulties on new phenolic insulation board production line, this study designed a synchronous fixed-length system. On the basis of analyzing system workflow, this system took PLC as the main control unit, used photoelectric encoder to measure the plate traveling motion and velocity, got PLC to control servo system to achieve the target of the synchronous tracking and fixed-length cutting on insulation board by synchronous cutting car, so as to increase cutting accuracy and production efficiency. This design includes the software and hardware designs of the control system and takes the PID control algorithm in accurate positioning. This system properly realizes the synchronous fixed-length cutting of new insulation board, has high cutting accuracy, operates steady, meets the control needs of new phenolic insulation board on production line, and largely improve production efficiency.
The Effect of Trace Boron Element on Local Corrosion Resistance of Casted 0.04C-16Cr Ferritic Stainless Steel
Authors: Guo Tie Ming , Zhang Ding Cang , Hui Zhi , Han Chang Song , Zhao Li Ming
Published: December 2011

0.04C-16Cr and 0.04C-16Cr containing 26ppm B ferritic stainless steels were smelted by using a vacuum induction furnace. Then 65% boiling nitric acid method and the electrochemical potentiokinetic reactivation method (EPR) were used to research their intergranular corrosion sensitivity. Meanwhile, electrochemical test method (Tafel polarization curve method, the anode circular polarization curve method) and chemical immersion method were used to research their pitting corrosion resistance. The results showed that the corrosion rate of 0.04 C-16Cr stainless steel containing 26ppm B in 65% boiling nitric acid is lower than that of 0.04 C-16Cr stainless steel. The reactivation rate of 0.04C-16Cr containing 26ppm B in dilute sulphuric acid medium significantly reduced compared with that of 0.04C-16Cr. The pitting corrosion potential, self-corrosion potential and the value of (Eb-Ep) of the stainless steel containing with 26ppm B in chlorideions medium reduced, while the corrosion rate increased compared with the stainless steel without B addition. It indicates that trace boron addition improves the intergranular corrosion resistance and repair ability of the passive film of the 0.04C-16Cr ferritic stainless steel after pitting corrosion process in chloride ions medium, but it also promotes the pitting corrosion tendency of the steel. Besides, introduction B to 0.04C-16Cr ferritic stainless steel reduces the steel’s corrosion resistance in active dissolved zone and promotes its intergranular corrosion tendency in chloride ions medium. The electrochemical characteristics of local corrosion are consistent with the results of chemical immersion test.
Thermodynamic Research on Smelting Master Alloy by Direct Reducing Boron Oxide
Authors: Zhao Ding Guo , Wang Shu Huan , Wang Cui Liang , Gao Jv
Published: December 2011

The boron is one of the important elements to amorphous alloy. Researched the basic reaction of direct reducing boron oxide, and drawn the thermodynamic status diagram. The reducing reaction is much more relation with composition activity of slag and melt. The boron distribution ratio between slag and iron was calculated and analyzed the main factors of slag basicity, compositions of alloy and reaction temperature for affecting boron distribution ratio.
Test Research on Single Point Impact of a Liquid Foundation
Authors: Cao Yun
Published: December 2011

Dynamic compaction is a widely used method for subgrade treatment due to its merit. This article presented example of dynamic compaction test in a liquid foundation project and investigated the relationship between settlement, ground heave and drop counts, the relationship between horizontal displacement and depth of soil, the relationship between drop counts, depth, horizontal displacement and pore water pressure, and the relation curve of pore water pressure and time during single point impact test. According to the conclusion before and after the testing, some appropriate engineering parameters were obtained and some advices were put forward.
Research on Effect of Temperature on Nitrogen Solubility in Steel
Authors: Wang Shu Huan , Wang Cui Liang , Zhao Ding Guo , Gao Ju
Published: December 2011

The experiments of high nitrogen steels refining have been researched with high pressure and bottom-blown nitrogen in laboratory. We can gain high nitrogen nickel-free stainless steels that its content is more than 0.9%. The research indicates that the temperature influences nitrogen content greatly in the processes of smelting and concreting. The results are shown that saturated nitrogen content in steel increased slightly. When the temperature is as high as 1913K, the nitrogen content can reach 1.191%.
Relationships between δ→γ Phase Transformation and the Crack Formation in Continuous Casting Slabs
Authors: Chang Guo Wei , Li Qing Chun , Chen Shu Ying , Yue Xu Dong , Yu Yan , Wang Cheng Quan
Published: December 2011

The δ→γ phase transformation in the steel was studied in detail, and the relationship between δ→γ phase transformation and the crack formation in continuous casting slabs was discussed as well. The results indicate that the micropores are formed at the positions where δ-phase transformation terminates during the δ→γ phase transformation for low-carbon non-peritectic steel. The micropores will also be formed at the positions where the peritectic reaction of the steel terminates, then the pores are remained on the grain boundary of γ-phase when γ-phase becomes granulated. The micropores distributing on the grain boundary of γ-phase is one of the results for the crack formation of continuous casting slabs and the obvious plasticity decrease of δ-phase zone in the steel. The theoretical analysis results are basically consistent with the experimental results.
Effect of Heat Treatment on Microstructure and Mechanical Properties of 800MPa Grade Ultra Low Carbon Bainite Steel
Authors: Wei Zhan Lei , Zuo Long Fei , Ma Ben , Zhang Li Xian , Zhang Hong , Wang Zi Dong
Published: December 2011

A new kind of bainite steel with ultra-low carbon content and Nb, Ti alloys has been developed. By applying thermomechanical control process, water quenching and tempering at different temperature, excellent properties have been obtained when tempered at 450°C, with the yield strength of 813MPa and elongation of 16.2%. The morphology observed by SEM shows that the microstructure consists of fine lath-shaped bainite, polygonal ferrite, quasi-polygonal ferrite and a small fraction of residual austenite or martensite-austenite constituents. In a TEM study plenty of precipitates with the size about 5-10nm were observed interacting with the dislocations, which is very significant for the optimization of strength and ductility.
Microstructure and Texture Evolution of Strip Casting Fe-6.2wt%Si Steel
Authors: Liu Hai Tao , Liu Zhen Yu , Sun Yu , Qiu Yi Qing , Wang Guo Dong
Published: December 2011

An Fe-6.2wt%Si as-cast strip with equiaxed grains and obvious {001} fiber texture was produced by twin-roll strip casting process. The as-cast strip was successively performed by hot rolling, warm rolling and annealing. The microstructure and texture evolution at each process stage were investigated by using electron backscatter diffraction and x-ray diffraction. It was found that the finally annealed sheet was characterized by large grain size, mild γ-fiber texture and obvious {001} fiber texture. Therefore, a high magnetic induction and a low core loss were obtained in the sheet.
Effects of BN Dopant on Electrical Characteristics of Barium-Excessive BaTiO3 Ceramics for Laminated Positive Temperature Coefficient Thermistors Fabricated by Tape Casting Technique
Authors: Chen Bin Bin , Gong Shu Ping , Liu Jian Qiao , Li Lian Hua , Zhou Dong Xiang
Published: December 2011

The barium-excessive BaTiO3 ceramics with BN addition for laminated positive temperature coefficient (PTC)thermistors are fabricated. The tape casting technique and reduction/reoxidation process are employed into the fabricating procedure. The influences of BN additive on ceramic characteristics are discussed. The addition over 5% leads to rectangular and abnormal large grains. The 5% BN-doped ceramics shows a resistivity of 233 Ω•cm and PTC jump of 3.4 orders of magnitude. The charge carrier density in grain bulk and acceptor state density at grain boundaries are evaluated. The correlation of BN doping amount with room temperature resistivity, PTC jump, reoxidation effect as well as charge carrier and acceptor state density are investigated.
Mechanism Analysis and Experiment Study on RC Composite Core Walls
Authors: Chang Wei Dong , Chang Yu , Lu Lei
Published: December 2011

Two 1/6 scale core walls specimens were designed，including a normal reinforced concrete core wall and a reinforced concrete composite core wall with steel truss. The experimental study on two core walls subjected to combined action of compression, bending moment, shear and torque, was carried out. Based on the rotating-angle softened truss model theory, this paper presents a three-dimensional model for analysis of reinforced concrete composite core walls with steel truss subjected to complex loading. Through the results of calculation coincided with the test well, this model can predict the ultimate strength of the load-carrying capacity of reinforced concrete composite core walls with steel truss, and provide a tool to obtain the entire load-deformation history.
Modal Analysis of Montmorillonite in Bentonites Using Phase Mixing Equation
Authors: Li Ge , Ma Hong Wen , Liu Mei Tang , Zhang Jia Ping , Wang Hong Li
Published: December 2011

Based on the mass balance principle, mineral contents of the bentonites from Yangxian of Shaanxi province, Queshan of Henan province, and Chifeng of the Inner Mongolia Autonomous Region were estimated by resolving the Phase Mixing Equation constructed from the data of X-ray diffraction, microprobe analysis of montmorillonite grains, and chemical anaysis of the bentonites. The crystal formulas of montmorillonite in the bentonites were calculated based on the anion hydrogen equivalent method. The cell lattice constants of the principal minerals in the bentonites were calculated with a FORTRAN90 program CELLSR. When compared with both methods of the methylene blue absorption and XRD Rietveld quantitative phase analysis, the Phase Mixing Equation was confirmed to be the most effective modal analysis method for determing content of montmorillonite in bentonites with several minerals coexisted.
Research on the Counterweight in the Process of Diamond Wire Saw Cutting Polysilicon
Authors: Zhang Liao Yuan , Wang Jian Guang , Yang Yong , Wang Chao
Published: December 2011

In the process of cutting hard and brittle materials , electroplated diamond wire saw cutting has been growing concern for its high-quality, high efficiency, environmental protection and other advantages. In this paper, the wire saw cutting trajectory equation and the mathematical model of counterweight were established and the variation law of counterweight was analyzed. In addition, the impact of counterweight on the processing efficiency, surface quality was studied on the USDW-1 type ultrasound diamond wire saw cutting machine by way of cutting polysilicon material.
Study on the Dielectric Properties of CaCu3Ti4O12 Ceramics by the Brickwork Layer Model
Authors: Zhang Yun Qiang , Su Li Qiu , Wang Xiao Fei , Wang Hui Xian , Li Li Ben
Published: December 2011

A brickwork layer model was used to investigate the dielectric properties of CaCu3Ti4O12 ceramics. It is equivalent to Debye model under the Maxwell- Wagner-type mechanism. Arrhenius relation could be obtained by the assumption that the grains in the CaCu3Ti4O12 ceramic are of semiconductivity. The dependence of the dielectric constant on the grain size and temperature were well fitted by the model.
The Simulation Study on the Rules of Spatial and Temporal Changes of Total Nitrogen in Semi-Aerobic Landfill Leachate in the Laboratory
Authors: Pang Xiang Rui , Huang Qi Fei , Pang Xiang Duo , Zhang Guo Dong , Wang Jie , Zhou Wei Jie , Tang Hai Yang , Liu Qiang
Published: December 2011

Two experimental equipments of semi-aerobic landfill and anaerobic landfill were constructed. The total nitrogen concentrations of leachate (Recorded as CTN) that located at the bottom of equipments were determined periodically (1 or 2 times per week), the variation laws of CTN that located at the bottom of two landfill equipments with time were researched, and the reasons for the differences were also analyzed; During the period that the degradation of the landfill waste came into a relatively stable stage, the leachate that located at each sampling points of upper, middle and lower horizontal sections of the landfill equipments was collected periodically, and the CTN was determined, the CTN　data of each point of upper, middle and lower layers were processed by using Surfer software respectively, and the spacial variation characteristics and differences of two landfill equipments were also discussed. The results indicated that the CTN of each point of the semi-aerobic landfill treatment were significantly lower than the corresponding anaerobic landfill treatment, the semi-aerobic landfill treatment could achieve the effective removal of total nitrogen from the leachate, and could accelerate the process of degradation stabilization and balance of total nitrogen in leachate.
Microwave Devulcanization of Waste Rubber with Inorganic Salts and Nitric Acid
Authors: Paulo Glauco Dias , Hirayama Denise , Saron Clodoaldo
Published: December 2011

Rubber wastes cause severe damages for the environment when unsuitably disposed in the environment and represent a challenger for mechanical recycling, because the vulcanized rubber is formed by a tridimensional network with intermolecular sulfur crosslinks. Microwave radiation can lead to the breaking of sulfur crosslinks and so enable the recycling of vulcanized rubbers. The aim of this work was to study the SBR devulcanization by microwave using inorganic salts and nitric acid. Soxhlet extraction and FTIR analyzes were carried out to evaluate the devulcanization degree and chemical modifications in the rubber structure. The results showed that the presence of carbon black in the rubber is an important factor for devulcanization and some metallic ions decrease the sulfur crosslink content. On the other hand, these ions promote the oxidation in the rubber.
Effect of Hydrogen Charging on Microstructure Morphology of Warm Rolled Low Carbon Steel
Authors: Riastuti Rini , Riyanti Purnama , Priadi Dedi , Siradj Eddy S.
Published: December 2011

Warm rolled deformation is one of deformation technique to improve the strength of steels through the refining grain size of ferritic microstructure. In application, low carbon steel which used in structural industry need some protection against corrosion attack, cathodic protection is usually applied combining with coating. Cathodic protection creates reduction reaction which produces hydrogen, and the hydrogen atom may diffuse into the crystal lattice lead to the Hydrogen Induced Cracking. The present study is to observe the morphology of microstructure influenced by hydrogen charging as the source of hydrogen which attacks the steel surface, and observed by Optical Microscopy and Scanning Electron Microscopy. After warm rolling of 650oC and 35% deformation, ferrite grain size is smaller than bulk material and the hardness value increasing. After tensile test of hydrogen charged steel found the ductile fracture, it means the smaller the ferrite grains size, the resistance of hydrogen attack is increase.
Synthesis of a Novel Fluorene Derivative for Polyfluorenes: 7,7'-di(5-bromothiophen-2-yl)-9,9,9',9'-tetraoctyl-2,2'-bifluorene
Authors: Li Li , Sun Xiao Xia , Wu Qiu Hua , Hu Yu
Published: December 2011

A new bifluorene derivative, 7,7'-di(5-bromothiophen-2-yl)-9,9,9',9'-tetraoctyl-2,2'- bifluorene, has been prepared over six steps. The compound with good solubility, electronic and optical properties may be a candidate for polyfluorenes and copolymers of fluorenes.
Study on Mechanical Behaviors in Friction Stir Welding of 6061-T4 T-Joints
Authors: Zhou Guang , Yang Xin Qi , Xu Xiao Dong
Published: December 2011

Friction stir welding (FSW) of T-joints composed by 3mm thick 6061-T4 alloy was presented and the influences of process parameters on hardness profiles and tensile strength were discussed specifically. Two low hardness zones on the skin and one low hardness zone on the stringer were found. Tensile behaviors of T-joints were examined in two directions—in skin direction and in stringer direction. It was found that the tensile strength ranged from 170~180MPa for all specimens in the skin direction. And the specimens failed in heat affected zone (HAZ) corresponding to the lowest hardness. In the stringer direction, most fractures occurred in the stringer. In all the cases, the specimens welded exhibited the best tensile strength with ω/v=1541/218 in the stringer direction. The ultimate tensile strength was equal to 83% compared to base material.
Study on In Situ Ti(CN) Particle Reinforce Composites Coating Processed by Nitrogen Shielded Arc Welding Technique
Authors: Li Jin Song , Hao Jian Jun , Ma Yue Jin , Li Sheng Li
Published: December 2011

An in-situ Ti(CN) particle reinforce composites coating was fabricated on Q235 steel substrate by nitrogen arc shielded welding technique which take the titanium powder and the graphite powder as original material. The microstructures, interracial behavior and phase of the coatings were investigated by scanning electronic microscope, X-ray diffractometer, microhardness tester, abrasion machine. The results show that an excellent bonding between the coatings and carbon steel substrate is ensured by the strong metallurgical interface and phase of the coatings are mainly composed of TiC0.51N0.12.The highest microhardness of the coatings reaches HV0.5810, which is about five times more than that of the base metal .The anti-abrasive test results show the coating has better anti-abrasive performance than base steel.
Experimental Investigation on High-Speed Milling of Aluminum Alloys
Authors: Liu Yong , Zhang Li Tang , Xu Zhi Hong
Published: December 2011

High-speed milling is recognized as one of rapidly development machining methods. The article gives details of machining experiments with different aluminum alloys. Through a lot of single factor experiments and the orthogonal multi-factor experiments, and also use method of semi-artificial thermocouple. This paper mainly studies influence of surface roughness and residual stress with changed rotate speed, tooth load and radial depth of cut, and changed law of processing temperature for rotate speed. Though experiments shows that enhancing rotate speed may reduce surface roughness and residual stress within certain limits and the result of experiments is not agree with Carl Salomon’s theory.
The Research on the Algorithm of Rubber Parts Forming Die Dimension Based on Mid-Difference Value Method
Authors: Han Zhi Ren , Geng Xu , Yuan Ze Bing , Wang Guan Long
Published: December 2011

It mainly focuses on the research of the occurred problems and the suggested solutions when the dimension of the injection part die is calculated. The algorithm we usually use in enterprises is mid-value difference method, but it often appears parts working dimensions out of tolerance; So a compensatory algorithm based on mid-value difference method was developed, and the compensation algorithm and modified formula used in the thickness direction are put forward for sheet part. A series of sheet part are analyzed by ANSYS thermal transient analysis module, and the parameters in the compensation algorithm in the thickness direction are determined. The compensation results show that parts working dimensions in the thickness direction is in tolerance.
Numerical Simulation of Fiber Orientation of Short Fiber Reinforced Polypropylene in Injection Molding
Authors: Liu He Sheng , Xiong Ai Hua , Huang Xing Yuan , Lai Jia Mei
Published: December 2011

Based on generalized non-Newtonian fluid with seven parameters Cross-WLF viscosity model and modified 2-double Tait model, the numerical simulation was carried out for the short glass fiber reinforced PP injection molding process of rectangular part. The influence of main process parameters on fiber orientation is investigated. The results show that fiber orientation can be generally divided into three-regional layers in injection molding, that is outer-surface, subsurface and core layer. The degree of fiber orientation in subsurface layer is the highest and that in core layer is the lowest. The influence of fibers interaction coefficient (Ci) and fibers aspect ratio (re) on fiber orientation is significant. There is obvious difference between simulation results and practical results without consideration of Ci. The effect of melt temperature, mold temperature and cooling tubes number on fiber orientation isn’t obvious.
Characteristic Analysis of Grinding Point Movement in Grinding Aspheric with Arc Envelope Grinding Method
Authors: Zhou Xu Guang , Yan Qiu Sheng , Dai Jue , Kong Ling Ye
Published: December 2011

It is an important method to machine revolution aspheric with Arc Envelope Grinding Method（AEGM）. In this article, the relationship between the grinding point of the wheel and its position is analyzed, and motion law of the grinding point is discussed in grinding aspheric. According to motion velocity of the grinding point , the concrete position of severe wear for the wheel can be calculated out theoretically. It is possible to achieve even angular velocity of the grinding point by adjusting the wheel feed rate, so the angular velocity of wheel movement is optimized, which provide confirm base for improving the precision of grinding aspheric.
Evaluation of Welding Residual Stress Based on Temper Bead Welding Technique
Authors: Shi Xian , Zhang Yi Liang , Zhao Jian Ping , Gou Rui Bin
Published: December 2011

To reduce welding residual stress (WRS) of a class 3 pressure vessel during the reconstruction, temper bead welding technique (TBWT) was applied to the container. To compare WRS causing by common welding and TBWT, WRS of the two different kinds of welded specimens of 16Mn steel were measured and evaluated by X-ray method. To study the effect of butt weld reinforcement height on WRS, welds with and without weld reinforcement were measured. The results show that longitudinal stress was reduced obviously and the lateral stress is the maximum principal stress for TBWT; WRS of TBWT T-shape specimens were obviously decreased which proves TBWT is better than common welding procedure; WRS was decreased by more than 25% after removing the weld reinforcement and further proves that it is one of effective ways to reduce WRS in engineering application.
Influence of Asymmetry on Extraordinary Optical Transmission through Periodic Arrays of Triangular Holes
Authors: Yin Wen Jing , Yu Li , Zhang Kai
Published: December 2011

The effect of asymmetry on extraordinary optical transmission (EOT) through arrays of triangular holes with acute angles was investigated using FDTD method. It was found that the transmissions are strongly dependent on the different linear polarizations of the incident electric field, and could be tuned by varying the asymmetry of arrays of triangular holes. It could be demonstrated that these properties were associated with the existence of channel plasmon-polaritons (CPPs), which make it possible to realize Fabry-Perot (FP) resonances inside the triangular holes. The results may be very useful for EOT applications which require high sensitivity on the polarization of the incident electric field and the shape of holes in the arrays.
The Mixing Condition and Mechanical Property of Friction Stir Welded Dissimilar Formed 3003 and 6061 Al Alloys
Authors: Xu Xiao Dong , Yang Xin Qi , Zhou Guang , Tan Bo
Published: December 2011

In the present study, AA3003, AA6061 were selected as the object to investigate the mixing condition and mechanical property of the dissimilar Friction Stir Butt Welding joint. Experimental results showed the two Al alloys of the joint were interwoven together in the river shape with an obvious gradient. When ω/v was moderate, the two kinds of materials can be better mixed together and improved the mechanical property. Meanwhile the bonding was complete under all the welding conditions. The joint coefficients could all achieve more than half of those of the base material and the best was 96% (ω=1541rad/min, v=142 mm/min).
Experimental Study of Vibratory Turning with Low Frequency of the Mechanical Vibration Device and on the Surface Texture
Authors: Song Jin Ling
Published: December 2011

Based on the engine lathe, the vibratory turning experiment system was built up with low frequency of the mechanical vibratory device. Orthogonal experiment was carried out for the findings of the chip configuration, chip breakage, and the surface roughness with relationship of the cutting engagement especially the combination of the vibratory frequency, amplitude, and the feed and cutting velocity. Regressive analysis was done for the empirical formula of the roughness with parameters of vibratory turning engagement. From the experiment it has been shown that the higher the frequency is in vibratory turning, the smoother the machined surface is, other conditions being equal. The surface roughness increases with the feed, at the same frequency. The cutting tool was still smooth on the rake and flank and along the cutting edges all the time in vibratory turning. Because of the vibration and the lubrication the BUE can hardly be built up, being good for the surface integrity.
Corrosion Behavior of 6082-T6 Al Joint Welded with Twin Wire MIG
Authors: Ruan Ye , Qiu Xiao Ming , Gong Wen Biao
Published: December 2011

Corrosion behavior and mechanism of 6082-T6 Al-alloy twin wire MIG welded joint under salt spray corrosion in 5 wt.% NaCl solution were investigated via laser scan confocal microscope, scanning electron microscope spectrometer and infrared spectroscope. Pitting was seen on both weld seam and the base metal resulted from Cl-. Uniform corrosion was also seen on the weld seam, grain boundaries had been corroded and approximate circular corrosion channels were observed, while evident pitting corrosion was seen in the base metal. Corrosion resistance of the base metal was better than that of the weld seam. The main corrosion products were composed of Al2O3, Al(OH)3 and AlCl3•6H2O. Corrosion had a slight effect on the test sample's tensile strength, and serious results on the plasticity of the joints. In addition, transition from prior corrosion ductile to after corrosion hybrid brittle and ductile morphology was also found on the fracture surface.
Gas Forming a V-Shape Aluminum Sheet into a Trough with Contour Like the Back of a Twin-Hump-Camel
Authors: Wang Jian Yih , Lee Shyong , Huang Jian Jia , Lan Hsien Chin , Hsu Chang Chuan
Published: December 2011

A ~1.2 meter long trough comprising of variable cross-sections, with the highest ratio of depth to opening width reaching 1.4, is gas-formed at 500°C with superplastic aluminum alloy 5083. It is a challenge to successfully make such an industrial scale part as demonstrated in this paper. Starting as an expanded V-shaped groove, pressurized gas is manipulated to flow into the forming die, and the pressure vs. time profile needs to be calculated. Thus, the flow stress in the deforming material is optimal to maintain desired strain rate correspondingly. Thickness distribution over the formed product is far from uniform. The other even undesired result is that the thinnest region suffers severe cavitation
Effect of Metal Inert Gas Welding on Microstructure and Mechanical Properties of Al-Zn-Mg Alloy
Authors: Wang Feng , Xiong Bai Qing , Zhang Yong An , Liu Hong Wei , Li Zhi Hui , Li Xi Wu
Published: December 2011

Abstract. The microstructure and mechanical properties of a metal inert gas welds in a medium strength Al-4Zn-1Mg alloy were characterized by optical microscope (OM), scanning electron microscope (SEM) and tensile tests. It is found that the joint of the alloy contained three distinctive regions, i.e. fusion zone, heat affected zone and base metal region. Extensive microhardness measurements were conducted in the weld regions of the nuggets exhibited a hardness loss in the fusion zone due to the loss of strengthening phases. Microstructural examination of the joints revealed typical eutectic structure was appeared in the heat-affected zone. Tensile properties of the joints were obtained by testing flat transverse tensile specimens, and the results indicated that tensile strength of these welds approached 83.3~84.2% of the base metal.
Optimization on Resistance Microwelding Procedure of Fine Copper Wire Based on Orthogonal Experiment Design
Authors: Chen Ping , Guo Zhong Ning , Mo Bing Hua
Published: December 2011

In this paper, an orthogonal experiment design method has been used to optimize the resistance microwelding (RMW) parameters for the fine copper wire and SUS304 stainless steel thin sheet welds. A L25(56) orthogonal array for three factors (welding current, weld time and electrode force) with five levels was used. Joint breaking force (JBF) and surface appearance were selected as the index of evaluation. The results show that welding current was the most influencing parameter on both joint strength and surface appearance, and weld time had the next most significant effect. The orthogonal experiment design method was proved to be a promising technique to obtain the optimum conditions for RMW of fine copper wire.
BP Neural Network Model for Seam Tracking Offset during High-Power Fiber Laser Welding
Authors: Mo Ling , Gao Xiang Dong , Wen Qian , You De Yong
Published: December 2011

Seam tracking is significant to obtain good welding quality. Aiming at establishing a model to detect and calculate the seam tracking offset during high-power fiber laser welding of Type 304 austenitic stainless steel plate butt joint welding, an infrared sensitive high-speed camera arranged off-axis orientation of laser beam was applied to capture the dynamic thermal images of molten pool. Six parameters such as the keyhole configuration parameters (include four parameters), keyhole centroid parameter and heat accumulation parameter were defined as the eigenvalues of seam tracking offset to determine the seam tracking offset between the laser beam and the desired welding trajectory. A BP neural network model was built to reflect the correlations between the defined eigenvalues and the seam tracking offset. The welding experiments confirmed that the seam tracking offset between the laser beam focus and the welding seam could be monitored and calculated by the BP neural network model effectively.
Development of Tooling Cost Model for High Speed Hard Turning
Authors: Adesta Erry Yulian Triblas , Al Hazza Muataz , Agusman Delvis , Sutjipto Agus Geter Edy
Published: December 2011

The current work presents the development of cost model for tooling during high speed hard turning of AISI 4340 hardened steel using regression analysis. A set of experimental data using ceramic cutting tools, composed approximately of Al2O3 (70%) and TiC (30%) on AISI 4340 heat treated to a hardness of 60 HRC was obtained in the following design boundary: cutting speeds (175-325 m/min), feed rate (0.075-0.125 m/rev), negative rake angle (0 to -12) and depth of cut of (0.1-0.15) mm. The output data is used to develop a new model in predicting the tooling cost using in terms of cutting speed, feed rate, depth of cut and rake angle. Box Behnken Design was used in developing the model. Predictive regression model was found to be capable of good predictions the tooling cost within the boundary design.