bluuebunny/crossref_metadata_2025 huggingface dataset:
Macro Analysis Would Like to Drop Half a Drop of Solution
Authors: Chen Ling
Published: July 2011

By strong alkali (acid) titration strong acid (alkali), alkali (acid) titration mono-weak acid (alkali), precipitation titration and coordination titration to drop by half a drop, and settling the titration error specific terms, to illustrate the macro titration analysis would like to have drop half a drop of a solution. When strong alkali titrate strong acid or monobasic weak acid, there is no need to drop half a drop. As strong acid titrate strong alkali, there is must to drop half a drop as methyl orange for indicator. But phenolphthalein as indicator, there is doesn't need to drop half a drop. Strong alkali titrate monobasic weak acid, there is no need to drop half a drop. Eriochrome Black T for indicator titrate magnesium ion with EDTA, there is must to drop half a drop. Titration of zinc by EDTA, don't need to drop half a drop. Titration chloride ion with Moore method can not drop half a drop.
Computing Acceleration of FMM Algorithm on the Basis of FPGA and GPU
Authors: Chai Ya Hui , Shen Wen Feng , Xu Wei Min , Zheng Yan Heng
Published: July 2011

FMM is an efficient algorithm in computing N-body problem. This paper firstly subdivides the FMM into 10 procedures. Based on the analysis the computing type of each procedure, we choose key procedures accelerated on FPGA, GPU and Cell BE. And then we present the speedup ratio of each accelerated procedure through experiments. Finally we analyze the computing characteristic of FMM on the computing architecture on accelerator FPGA and GPU on the side of P, M and C.
Sampling Distribution of the Coefficient of Variation when the Population Takes Normal Distribution N(0,σ2)
Authors: Xu Jian Mei , Bai Lun
Published: July 2011

The coefficient of variation of the raw silk size objectively expresses the fluctuating characteristics of the raw silk size, and is an important quality index in the development of the new standard used in the electronic testing for raw silk. This paper theoretically deduces the sampling distribution of the coefficient of variation of the normal population, justifies the theoretical results by computer simulation using Monte Carlo method, and thus afford important theoretical basis for the development of the new standards for the electronic testing of the raw silk size.
Perturbation Method of Light Scattering for the Probability Distribution Function of Particles’ Shape
Authors: Cui Qing Yi , Wang Ya Wei , Bu Min
Published: July 2011

In order to settle the influence of measuring results of particles with its shape-variety, the scattering pulse width and peak distribution and the relation of particles’ size and shape characters are systems analyzed based on the Mie theory and perturbation ameliorating method. In addition, a theorem of equivalence probability area is setup and a method of obtaining the probability distribution function of shape particles in real time is built. At last, the theories are validated in the experiments. The effect of the particles’ shape is modified and the accuracy of measurement of the particles’ size is improved effectively.
Numerical Simulation of Electromagnetic Induction Heating in the Material Heat Treatment
Authors: Chen Jian Min , Zhang Meng
Published: July 2011

The paper firstly introduces the principle and mode of electromagnetic induction heating. Accordingly the basic equations of electromagnetic field and temperature field in the heating material are derived from Maxwell's equations and heat conduction differential equations. Then give an example of the electromagnetic induction heating. With the application of ANSYS software, the one-dimensional finite element model of the heating material is built. And numerically simulate it by the means of the electromagnetic field and temperature field coupling in the ANSYS software. The influence of the material's physical parameters changing with the temperature and significant skin effect in the electromagnetic induction heating are considered. So the results are correct and reliable.
Wireless Sensor Network (WSN) Using in Tunnel Environmental Monitoring for Disaster Prevention
Authors: Chang Dave Ta Teh , Tsai Yuh Show , Lee Horng Cheh , Guo Li Lun , Yang Kai Chun
Published: July 2011

The research dealed with using Wireless Sensor Network(WSN) in the application of tunnel environmental monitoring purpose. First put of this study has concluded in Snow Mt Tunnel for Fire Exam testing.14 nodes have set up during testing.Typical WSN units developed by the research team with about 30 meters communication distance.This stage of study provides the significant data which collected by notebook PC were performed well.Fire dynamic simulator (FDS)software confirmed the monitored information (temperature)，and support the second part of WSN application study.In second part of study，completed WSN are going to be established in Guan Yin Mt Tunnel. Not only temperature MEMS sensor was used，but also CO2/CO were built in the node. In house study has completed，and 53 nodes were produced，and initial set up test has concluded for the ongoing program. WSN system will be installed in the following stage and the completed monitored information will to be expected and performed.
The Research on Green Project Management Evaluation Method of Construction
Authors: Qi Bao Ku , Qu Yu , Zhao Jing Ming
Published: July 2011

In this paper, green construction project management concepts, analysis the green project management research status of our country, on this basis, establish a green construction project management evaluation system, and study and explore systematically on the evaluation methods. In the low-carbon economy, this increase of green construction project management has important theoretical and practical value.
Emergence of Difficulties among Organizations in Applying Supply Chain Management
Authors: Rahman Mohd Nizam A. , Manzouri Malihe , Arshad Haslina
Published: July 2011

In this study implementing Supply Chain Management (SCM) among Malaysian automotive industries are considered to recognize what kind of problems suffered by those organizations when SCM was applied. Survey questionnaire was used to gather the data needed. The questionnaire was distributed to 300 Malaysian’s automotive organizations and a total of 62 replies were usable. The survey reveals that companies suffer from the lack of information as major difficulty during implementing SCM. The findings of this research would give invaluable information to all researchers and practitioners in the field of SCM.
Numerical Simulation of Rolling Process and Microstructure Evolution of AM50 Mg Alloy during Hot Rolling Process
Authors: Hua Fuan , Zhang Chao Yi , Li Qiang , Yu Bao Yi , Liu Wei Hua , Li Run Xia , Xie Shui Sheng , Huang Guo Jie , Cheng Lei , Fu Yao , Wang Hao
Published: July 2011

In order to optimize rolling process of AM50 Mg alloy, numerical simulation method is adopted to find reasonable process parameters. And then, the metallograph was viewed to find the microstructure evolution during hot rolling process. Through numerical simulation it is found that while the heating temperature is 420 and the train less than 0.33 each time. Through 10 times rolling, a 10mm thickness plate was rolled to 0.5mm, and its grain size also decreases to 10μm, which indicates that AM50 Mg alloy can be formed by hot rolling method.
Three Dimensional Prediction of Microstructure Evolution and Mechanical Properties of Hot Strips
Authors: Zhu Guo Ming , Lv Chao , Kang Yong Lin , Cheng Guo Guang
Published: July 2011

With the 3D thermal mechanical coupled elastic-plastic finite element method and by simulating the whole rolling process of 1250mm×20mm C-Mn hot strips, this paper obtains the temperature field and deformation result of the rolling process. By comparing the temperature drop curve with the measured data in the field, it shows that the simulation result is close to the real situation. Based on the thermal mechanical coupled simulation of the whole rolling process, this paper completes the computational simulation of the prediction of the 3D microstructure and property of hot strips by using the relevant microstructure evolution and property prediction models and advanced C language programming, thus providing reference for the property prediction of new products and processes.
A Comparative Study of Zirconium-Based Coating on Cold Rolled Steel
Authors: Wang Shuang Hong , Liu Chang Sheng , Wang Lei
Published: July 2011

An experimental zirconium-based conversion coating on cold rolled steel was investigated in the present work. The following tests on differently pretreated panels, such as bonderite®NT-1, oxsilan®9810/1 and lz-4356, were conducted to evaluate corrosion performance include adhesion test, T-bent test, neutral salt spray test and warm salt water dipping test and electrochemical studies were also performed. The whole results showed that the experimental zirconium-based conversion coating had well-pleasing corrosion protection properties and adhesion properties, and similar lever performance as compared to the other industrial coatings. The experimental zirconium-based conversion coating was very hopeful about industrial application.
Warm Forming Simulation of Dual-Phase Steel Tailor-Welded Blanks Based on Thermo-Mechanical Coupled Method
Authors: Ding Yi , Liu Xiang Jun , Guo Yu Qin , Chen Wei
Published: July 2011

A thermo-mechanical coupled finite element model for warm forming of dual-phase steel (DP) laser tailor-welded blanks (TWBs) was established based on ABAQUS software. The isothermal deep drawing of rectangular cups at elevated temperatures and the non-isothermal deep drawing at the temperature of 400°C were simulated. The distributions of temperature and differences between the isothermal and non-isothermal conditions were discussed. The results show that the temperature has great effect on the warm forming of DP-TWBs, and it achieves the best formability at the forming temperature of 400°C, and the non-isothermal deep drawing can further improve the warm formability.
Error Coupling Analysis and Pre-Compensation in CNC Machining Based on the Empirical Formula
Authors: Fan Kai Guo , Yang Jian Guo , Yang Li Yan
Published: July 2011

In CNC machining, various errors, which caused by the cutting process and the structure of the machine tool, affect the machining accuracy of the machined parts. To analyze the relationship among the cutting force induced error, the thermal deformation, and the tool wear induced error, the empirical formula is employed in this study. The result shows that the cutting force is the main factor which affects the error distribution of the machined parts; the thermal deformation and the tool wear induced error change the error distribution. Furthermore, all the errors are coupling each other. To improve the accuracy of the machined parts, a pre-compensation method is proposed. To achieve the real-time error compensation, an application is designed to calculate the coupling error and to generate the NC code. Using the pre-compensation method, the maximum error is reduced from 0.015 mm to 0.002 mm. The error is compensated by 86.7% compared with no compensation.
Finite Element Analysis for Wall Thickness Variation of Seamless Tube in Stretch Reducing Rolling Process
Authors: Yu Hui , Chen Yong , Bai Xiang Zhong
Published: July 2011

According to the geometrical characteristic of workpiece and groove in the stretch reducing rolling process, three-dimensional elastic-plastic finite-element analysis model was established to simulate the metal deformation, the regularities of distribution of wall thickness of transverse direction longitudinal direction were investigated. The analysis was verified by comparing finite element analysis results with on-line measurements. The length of crop ends was determined as well as product bore polygonization. The study provides the foundation for analyzing product defeat and instructing technological design.
An Experimental Investigation on Profile Forming of an End Cap Using Al 3003 (O)
Authors: Shanmuganatan S.P , Senthil Kumar V.S
Published: July 2011

The feasibility of using modern computers in manufacturing has evolved an era in the development of several new sheet metal forming process. The concept of profile forming technique has been investigated for production of sheet metal components. Profile forming is a very promising technology to manufacture sheet metal producs by CNC controlled movement with simple forming tool. Profile forming was developed as a flexible, alternative manufacturing method to effectively prototype stampings and produce in small lots. Cylindrical Cup is formed on Aluminium sheet of grade Al 3003 (O) without using punch and die. Formability of material, maximum wall angle, Surface roughness, thinning of sheet and Microstructural characteristics of Aluminium sheet are studied.
Optimization of Forming Technique during Necking Extrusion of Drill Pipe Joints
Authors: Guo Yong Qiang , Xu Chun Guo , Ren Guang Sheng , Liu Gui Hua
Published: July 2011

By using finite element method, the causes of forming defects such as shortage of material and punching recess thickened during drill pipe joints forging were studied and some solutions were put forward. According to the numerical simulation results, one forming defect named shortage of material caused by the metal irregular flow at the bottom of necking die, which can be resolved by reducing the die forming-angle and increasing the width of the punch. On the condition with D0/d0≤2.6 (D0 refers to outer diameter, d0 refers to inner diameter), necking process can be completed with one-step backward extrusion. The thicker punching recess is formed by the accumulated metal which was scraped by the punch during necking extrusion. This kind of defect can not be eliminated, but can be minimized by improving friction conditions.
The Study and Application of Metal Injection Molding of Fe-Ni-Co Alloy
Authors: Zhang Chi , Xiang Rong , Luo Jing
Published: July 2011

Packaging material of electronic goods requires higher strength, higher reliability, and lower expansion coefficient .What’s more, forming process is important. The Fe-Ni-Co alloy has a low expansion coefficient and good structure stability, so it is often used for packaging materials for the semiconductor industry. The shape of electronic packaging parts is so complex that the traditional manufacturing processes are difficult to form and it costs more, which greatly limits the application of Fe-Ni-Co alloy in complex electronic packaging parts. Metal (ceramic) powder injection molding (MIM / CIM) is a new near net shape technology. In this paper, we analyze the structures and characteristics of Gehause which is an electronic packaging box that has been successfully used in the MIM process to produce it. In this process, we adopted a new material of Fe-Ni-Co alloy, a specia binder and SPC (Statistical Process Control) technology which control parameters of injection molding and weight of parts. After sintering, the mechanical properties and precision of finished products meet all demands. Therefore, MIM technology can greatly improve the production efficiency, save materials and reduce production costs in producing Gehause.
Wettability of Molten Ti on ZrO2
Authors: Liu Ai Hui , Li Bang Sheng , Sui Yan Wei , Guo Jing Jie , Zhu Yu Fu , Ding Hong Yan
Published: July 2011

The wettability between pure liquid titanium and calcia-stabilized zirconia was studied in argon atmosphere. The micrographic observations made on cross section perpendicular to the interface using SEM showed that interfacial reaction occurred. However, the contact angles were larger than 90°within experimental duration.
Study on the Properties of Magnetization Modified Sodium Silicate Sand
Authors: Fan You Fa , Li Dong Nan
Published: July 2011

Based on the magnetization technological parameters optimized of sodium silicate, the properties of modified sodium silicate sand with ester hardening have been systematically investigated. The results indicated that the bonded strength of sodium silicate treated in the magnetic field may be increased by 30%~40%, the minimum addition content of sodium silicate in mold sand may reduce to 2.5%, and thus it improves markedly the collapsibility of the sodium silicate bonded sand. The used time of modified sodium silicate sand increases to 25%, but the effect of magnetization of sodium silicate will be disappeared after 24 hours, and the magnetization decaying speed enhanced with increasing the modulus of sodium silicate. The magnetization modification has a good effect on the high modulus sodium silicate than the low modulus sodium silicate.
Study on Influencing Factors of the Seaming of Knitted and Woven Fabrics
Authors: Lin Bin , Li Zhe
Published: July 2011

Clothing combining knitted and woven fabrics gets more and more favor of people. In this study, three knitted fabrics and three woven fabrics which are common on market were selected and seamed. The tensile breaking strength, elongation at break and the fracture reason of the joint of knitted and woven fabrics were tested using the one-way vertically stretching method. The test results were analyzed and it was found there are many factors affecting the seam strength of knitted and woven fabrics. Experiment shows that the main factors include: stitch density, joint method and choice of the joining material. The study of this subject provides the basis for designing better joint wear and improving sewing quality and efficiency.
Research on Vibration Grinding Finishing Technology
Authors: Zhang Peng , Guo Xing Yu , Guan Zhi Guang , Liu Ai Hua
Published: July 2011

In mechanical manufacturing, the traditional methods adopted for finishing is not only high labor intensity, but also difficult to reach the surface roughness and requirements. The vibration grinding finishing process method is put forward, and the surface finishing experiments for spiral nozzle which is one of the important parts for aeroengine are carried. It can be seen from the experimental results that the vibration grinding process method can reach the finishing effect. Compared with the common grinding method, the vibration grinding has the features of high efficiency and high quality, etc. The vibration grinding new process method has high practical value.
Numerical Simulation and Experimental Study on Warm Forging Process of Half Axle Bevel Gear
Authors: Tong Ying
Published: July 2011

According to the shape character of half axle bevel gear forging a process based on closed-die forging scheme was proposed. Based on a series of simulation the influence of initial forging temperature on forming force, the influence of web thickness and web position on stress, damage factor and forming force were analyzed. According to numerical analysis the web dimensions and forging temperature which ensure a minimum stress, a minimum damage factor and a proper forming load were achieved. The forming result was simulated and evaluated, and the forming load was controlled under 760ton. At last the research project got good test verifying.
Assessment of Factors Influencing Tool Wear on the Machining of Nimonic C-263 Alloy with PVD Coated Carbide Inserts
Authors: Ezilarasan Chakaravarthy , Zhu Ke , Velayudham A , Palanikumar K.
Published: July 2011

Nimonic C-263 alloy is extensively used in the field of like aerospace, power generators and heat exchangers due to its higher thermal properties. In this work, an attempt has been made to investigate the effect of the cutting parameters (cutting speed, feed rate & depth of cut) on tool wear (flank wear) in the machining of this alloy with a PVD coated carbide insert. The experiments were conducted using Taguchi’s experimental design. A second order response surface model has been established between the cutting parameters and flank wear using response surface methodology. The predicted optimal value of flank wear for coated carbide is 0.190mm. The results are confirmed by conducting verification experiments.
Study on Cutting Force of Diamond Cutter in Special-Shaped Stone Processing
Authors: Huang Bo , Liu Zeng Wen
Published: July 2011

The cutting force is the key factors influencing the processing precision and efficiency in special-shaped stone production. In this research, the cutting force is measured and analyzed in the process of special shaped cutter cutting stone. It is found that the relationship of cutting force with peripheral speed of cutter is nearly inverse proportional. The cutting force becomes smaller and smaller as the peripheral speed of cutter increases. The relationship of cutting force with feed rate is nearly proportional. The cutting force becomes larger and larger as the feed rate increases. The relationship between Fx, Fy and Fz is Fz > Fx > Fy. Enhancing the peripheral speed of cutter is a better way to increase the material removal rate.
An Experimental Investigation of the Laser Milling Process for Polycrystalline Diamonds
Authors: Wu Qi , Wang Jun
Published: July 2011

An experimental study of the pulsed laser milling process for a sintered polycrystalline diamond is presented. The characteristics and quality of the cavities machined with a Yd laser under different pulse energies, pulse overlaps, scan overlaps and numbers of passes are discussed, together with the effects of these parameters on the cavity profile, depth of cut and surface roughness. A statistical analysis is also presented to study the relationship between the process parameters and surface roughness. It shows that the optimum pulse overlap and pulse energy may be used to achieve good surface finish, whereas scan overlap and number of passes can be selected to improve the depth of cut without much effect on the surface finish.
TZM Alloy TIG Welding Process and Microstructure of Welded Joints
Authors: Wang Hua , Zhang Yun Peng , Zhang Xiao Yu
Published: July 2011

In this paper, the effect of welding current of the tungsten inert gas arc (TIG) welding process on weld quality of TZM alloy was investigated and the fracture microstructure and mechanical properties of the welding joints of TZM alloy was analyzed by x-ray flaw detection, metallographic microscopic analysis, scanning electron microscopy and mechanical properties test. The results indicate that the weld bead with excellent mechanical properties can be obtained using the welding process parameter with the welding current of 210A, welding speed of 4 mm/s and the argon gas flow rate of 8~12 L/min. The microstructure of weld presents the large columnar grains in the center of the weld bead and the equiaxed grains in heat-affected zone instead of the lamellar fiber texture of the TZM alloy matrix, which resulted in the weakened strength of the matrix and the improved plasticity of it.
Study of Laser Cladding Novel Co-9Al-7.5W Superalloy on 304 Stainless Steel
Authors: Xu Yang Tao , Zhao Wen Jun , Xia Tian Dong , Wang Xiao Jun
Published: July 2011

In this paper, laser cladding was deposited Co-9Al-7.5W superalloy on 304 austenite stainless steel plate and cladding layer shape, dilution, Vickers hardness, microstructure and distribution of alloying elements were investigated. It was found that laser cladding layer has the characteristics of large dilution rate, fine microstructure, narrow heat-affected zone (HAZ), narrow alloy elements segregation, high Vickers hardness, high contents of alloying elements and low contents of Fe in the cladding layers.
Study of Silica-Titania Mixed Flux Assisted TIG Welding Process
Authors: Tseng Kuang Hung , Wang Wei Chuan
Published: July 2011

An activated flux assisted tungsten inert gas (TIG) welding of type 316L stainless steel was investigated. SiO2-TiO2mixed powder was selected as the activated flux. Mixed fluxes effect on the surface appearance, weld morphology, and ferrite structure were investigated. The results showed that TIG welds surface produced with flux contributed to the formation of residues. The 80% SiO2+ 20%TiO2mixture can produce the greatest improvement function in TIG penetration. Silica-titania mixed flux assisted TIG welding can increase the ferrite content of stainless steel weld metal.
Effect of Heat Input on Toughness of Deposited Metal at -40οC of Self-Shielded Flux-Cored Wire
Authors: Song Shao Peng , Li Zhuo Xin , Li Guo Dong , Zhang Tian Li
Published: July 2011

The effect of welding heat input ranging from 1.507 KJ/mm to 2.987KJ/mm on low temperature toughness of deposited metal made by self-shielded flux-cored wire has been investigated. The results showed that low temperature toughness decreased with the increase of heat input, and the impact fracture changed from ductile to cleavage fracture. In addition, the chemical compositions demonstrated a slight tendency to decrease with increasing heat input. While, heat input has little effect on inclusions of deposited metal. Higher heat input lead to grains coarsened further, reduced acicular ferrite and granular bainite, and increased polygonal ferrite, which mainly lead to toughness decreased.
Research and Development of High Energy Pulse Precision Cold–Welding Technology
Authors: Meng Ling Dong , Liang Zhi Jie , Zhang Qing , Yang Jun Wei
Published: July 2011

High energy pulse precision cold–welding technology is a new welding technology that using high-energy pulsed, which arc produced between tungsten electrode and the workpiece, to melt the base metal and welding wires quickly. The quality and accuracy of this technology are equal to laser welding. It can repair the surface of parts, pitting, cracks and other defects of special-shaped surface. This article discusses research process of the High energy pulse precision cold–welding technology and its working principle, performance characteristics and equipments. It also presents the technology of cold welding materials and processes to explore the High energy pulse precision cold–welding technology’s potential application and future development in the field of surface engineering.
Novel Optical Fiber Gas Sensing System Based on FBG Filtering
Authors: Wang Shu Tao , Zhang Peng Wei , Gong Le , Shao Xiao Qing
Published: July 2011

Based on law of Beer-Lambert, a novel optical fiber gas sensing system is designed to determine the concentration of gas. The narrow-band filtering characteristic of optical fiber Bragg grating is used by this system to produce the narrow spectrum light signal which is wanted in difference absorption measuring. The system has full optical fiber structure, which is mainly composed by super luminescent emitting diode (SLED), optical fiber of 10km, optical fiber gas detector, optical fiber isolator, optical fiber coupler network, optical fiber detecting grating, photoelectric detector and data processing unit. The aspheric objective optical fiber collimator is adopted by this system to compose optical fiber gas sensing detector, which enhances the optic stability of the detector, diminishes the injection loss and makes the echo signal of the optical fiber detector greatly diminished. Experimental data and results show that this system has its feasibility and it can be used for real time monitoring of gas concentration in the domains of colliery and natural gas station, etc.
Efficient Synthesis, Photochromism and Application of a Photochromic Diarylethene Bearing a Benzene Unit
Authors: Wang Ren Jie , Liu Gang , Xia Hong Ying , Cui Shi Qiang
Published: July 2011

A novel photochromic diarylethene bearing a six-membered aryl unit, 1-[2-methyl-5-(3-fluorophenyl)-3-thienyl]-2-(2-methoxylphenyl)perfluorocyclopentene (1o), was synthesized and its photochromic properties, fluorescence switch and optical recording were investigated in detail. This compound exhibited remarkable photochromism, changing from colorless to blue after irradiation with 297 nm UV light both in solution and in PMMA film, respectively. The new diarylethene also exhibited excellent fluorescence intensity and fluorescence switches by photoirradiation in hexane solution. Finally, photo-mode rewritable optical storage using 1o was performed. The images demonstrated that the compound as optical storage material was very sensitive responding to 633 nm recording laser, and the recorded-signals were provided with high S/N ratio.
Efficient Synthesis, Photochromism and Holographic Optical Recording of a Photochromic Diarylethene with a Isoxazole Unit
Authors: Wang Li Qin , Pu Shou Zhi , Yan Liu Shui , Cui Shi Qiang
Published: July 2011

A new unsymmetrical photochromic diarylethene 1-(2,5-dimethylisoxazolyl)-2-[(2-n-butyl-5-formylthiophenyl)] perfluoroncyclopentene (1a), was synthesized and its optoelectronic properties, such as photochromism in solution as well as in poly-methylmethacrylate (PMMA) amorphous films, and the fluorescence spectra of diarylethene 1a was investigated. The photochromic reaction kinetics indicated that the cyclization process of 1a belongs to the zeroth order reaction and the cycloreversion process belongs to the first order reaction.Using diarylethene 1/PMMA film as recording medium and a linearly polarized 633 nm laser diode for recording and readout, polarization multiplexed image recording can be carried out in this film, which illustrated that the diarylethene can be potentially used as holographic optical recording medium.
Annealing on the Electrical and Dielectric Properties of Barium Strontium Titanate
Authors: Dong Gui Xia , Liu Wei
Published: July 2011

The electrical and dielectric properties of Ba0.3Sr0.7TiO3 (BST), as a function of annealed temperature and oxygen partial pressure (P(O2)) , were studied in this paper. The resistivity data were fit to a p type model involving only doubly ionized oxygen vacancies, holes, and accidental acceptor impurities, and it decreased as P(O2) and temperature increased. The breakdown strength exhibited the same trend with resistivity. The breakdown strength exhibited the same trend with resistivity. The maximum dielectric constant of BST was observed under the lowest P(O2) at the temperature of 900°C. BST annealed under P(O2) of 0.1 atm at the temperature of 800°C obtained the highest volume energy storage density.
Efficient Synthesis and Properties of a Photochromic Diarylethene Bearing Thiophene and Isoxazole Moieties
Authors: Liu Hong Liang , Liu Gang , Cui Shi Qiang , Liu Wei Jun
Published: July 2011

A novel photochromic diarylethene based on isoxazole moiety was synthesized and its photochromic and fluorescent properties were also investigated. This compound exhibited reversible photochromism, changing from colorless to red after irradiation with UV light both in solution and in poly-methyl methacrylate (PMMA) amorphous film. Also, it exhibited remarkable fluorescence switching in the solid state. The results showed that the diarylethene exhibited a relatively strong fluorescence switch along with the photochromism from open-ring isomer to closed-ring isomer. Using this dithienylethene 1c as optical storage was performed successfully.
Microstructures of In Situ Synthesized ZrB2/AZ91 Magnesium Matrix Composite Synthesized by a New Method of Direct Melt Reaction
Authors: Wu Jiang Jing , Zhao Yu Tao , Zhang Song Li , Chen G. , Xu Xiao Li
Published: July 2011

In-situ ZrB2/AZ91 magnesium matrix composite was successfully synthesized with Al/K2ZrF6+NH4BF4by Direct Melt Reaction (DMR). The microstructures of the ZrB2/AZ91 magnesium matrix composite fabricated by direct melt mixing method were investigated. The results show that the size of ZrB2particles is less than 1μm and even reaches to 100nm and the shape, amount and size of the β-Mg17Al12phase in magnesium matrix composite have been greatly changed due to ZrB2heterogeneous nuclei.
Effects of Polypropylene Fiber on Shrinkage of Masonry Cement Mortar
Authors: Liang Na , Zhang Xiao Yan , Sun Li , Li Feng Lan
Published: July 2011

Experiments were carried out to investigate the dry-shrinkage of masonry mortar affected by mass content of polypropylene fiber. The results show that proper content of polypropylene fiber is helpful to effectively reduce dry-shrinkage of mortar especially in early age, the reduction relates to water to cement ratio of mortar. Meanwhile, the relationships of water to cement ratio and content of polypropylene fiber in affecting dry-shrinkage of masonry mortar are analyzed, which can be as reference for selecting such optimum values as water to cement ratio and content of polypropylene fiber in practices.
Analysis of CTOD Test for Proving Rings of Large-Scale Fully-Welded Ball Valves
Authors: Mo Chun Li , Tang Xing Wei , Guo Xu Ming
Published: July 2011

Fully-welded ball valves are widely used in the crude oil/natural gas transmission pipelines, and their quality has a direct bearing on the transportation safety of national energy. Two paralleled and symmetrical circular welds are used in the main welds of valve body, and the narrow-gap submerged arc welding (NG/SAW) is used in the welding groove. Because of conditional restrictions, it is impossible for the value to be post-weld heat treatment (PWHT). Therefore, the welds must have high impact toughness and strength. In order to study the welding performance of the base metal, SAW is used in the welding of proving rings of steel LF2 fully-welded ball valves. CTOD tests are applied to welding joints, and the result suggests that the minimum CTOD value of the valve’s welds and heat affected zone (HAZ) is more than 0.15mm. According to the criterion DNV-OS-C401, the welds in the fully-welded ball valve are safe enough without PWHT.
Effects of Gadolinium on Aging Behavior and Mechanical Properties of Mg-5Y-3Nd-Zr Alloy
Authors: Wang Li Dong , Xing Cheng Yao , Hou Xiu Li , Wu Yao Ming , Sun Jian Fei , Cao Zhan Yi , Wang Li Min
Published: July 2011

Mg-5Y-3Nd-Zr-xGd (x=0 and 4 wt.%) alloys were prepared by metal mould casting, and aging behavior, mechanical properties and fracture morphology were investigated. The result shows that after T6 treatment, the massive eutectic phase in as-cast alloys dissolved and finer Mg5RE phase precipitated dispersively in the matrix, and mechanical properties were improved simultaneously. Mg-5Y-3Nd-4Gd-Zr alloy exhibits good age hardening behavior and the peak hardness is about 20% higher than the Gd-free alloy. Gd addition can significantly improve mechanical properties of the alloy especially at the elevated temperature. The ultimate tensile strength and yield strength of Mg-5Y-3Nd-4Gd-Zr alloy at 250°C, with the value of 276 and 168 MPa, respectively, are over 20% higher than those of the Gd-free alloy. It is mainly attributed to the increase and homogeneous distribution of the fine heat-resistant Mg5RE precipitate in the matrix.
Bending Properties of Three-Layer Biaxial Weft Knitted Fabric Reinforced Composite Materials
Authors: Qi Ye Xiong , Li Jia Lu , Liu Liang Sen
Published: July 2011

In this paper, three-layer biaxial weft knitted fabric(TBWK) made of carbon fiber as inserted yarns and polyester yarns as knitted yarns , which is a kind of non-crimp fabric, has been impregnated with epoxy via RTM technique. The bending properties of the TBWK fabric reinforced composite materials with different fiber volume fraction have been investigated. The bending strength of TBWK reinforced composites with fiber volume fraction of 48.8% can reach 821.1 MPa. The results show that this kind of composites has good bending properties, and load - deflection curve shows obvious linear features.
Crystallization Kinetics of ZrCuAlSiY Bulk Metallic Glass
Authors: Zhang Bao Qing , Zhang Zhi , Cao Guo Hua , Yue Yun , Liu Bao Zhong , Mi Guo Fa , Wang Wen Kui
Published: July 2011

Zr45.1Cu42.3Al8.7Si1.4Y2.5(at. %) metallic glass alloy was prepared by using copper mould casting. The crystallization behaviors of the alloy during continuous heating are investigated mainly by differential canning calorimeter (DSC). The activation energies were obtained from the Kissinger and Doyle equations. The results show that the activation energies of glass transition (Eg), crystallization (Ex) and peak crystallization (Ep) are 365kJ/mol, 281 kJ/mol and 279 kJ/mol, respectively. The crystallization activation energies are all less than the corresponding data of ZrCuAlSi alloy, the results show that thermal stability was decreased with the Y addition.
Based on CSP Technics, the Experimental Research of Rare Earth Steel Hot-Rolled Deformation Behaviors
Authors: Liu Yu Yan , Li Xing Qian , Jin Zi Li
Published: July 2011

Based on CSP technics, using Gleeble1500-D hot simulation machine, making the single, dual, multi-pass compression experiment of Q345B steel with rare earth Nd respectively, different deformation conditions influencing Q345B steel of recrystallization behavior and the microstructure evolution rule in the hot rolling process have been studied. The results show that: the single, dual-pass experiments of Q345B steel with rare earth Nd are according with general experimental rules. According to single, dual-pass results, we establish multi-pass compression project. In that project, the grain samples with rare earth element Nd are finer than others. It explains that appending rare earth Nd has the obvious function of refining grains. At the same time, the degree of refining grains is different in the different project. It explains that in order to obtain fine grains, we should choose feat technics. By contrast, we can educe that the grains are more fine and uniform in a project.
In Situ Template Synthesis Titania Nanotube Array Films on Aluminum Plate
Authors: Jiang Wu Feng , Hao Su Ju , Ling Yun Han , Liao Jun Sheng
Published: July 2011

Titanium dioxide nanotube array films on aluminum plate were prepared via liquid phase deposition (LPD) method. The samples were characterized by field-emission scanning electron microscopy (FE-SEM) with energy dispersive spectroscopy (EDS), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR). The results show that the nanotube array films’ morphology depends on the anodic aluminum oxide (AAO) structure and deposition time. The titanium dioxide nanotube’s outside diameter is about 250 nm, the wall thickness is approximately 40 nm. The as-prepared TiO2array films are amorphous and anatase appeared after calcining at 400°C for 2 hrs. FT-IR spectrum indicates that there are lots of hydroxyl groups on the surface of AAO. When AAO was immersed into 0.1 M (NH4)2TiF6solution at room temperature, AAO was dissolved in the solution and the holes became wide. The hydrolysis reaction was shifted to the right-hand side, TiO2particles locked in-situ on the inner surface of the anodic alumina pore induced by hydroxyl group, thus nanotube array film was obtained.
Development of Electromagnetic Swirling Flow in Immersion Nozzle in Continuous Casting Process of Steel
Authors: Li De Wei , Su Zhi Jian , Sun Li Wei , Marukawa Katsukiyo , He Ji Cheng
Published: July 2011

Swirling flow in an immersion nozzle is effective on improving quality of casting block and casting speed in continuous casting process of steel. However, a refractory swirl blade installed in the nozzle is liable to cause clogging, which limit the application of the process. In this study a new process is proposed, that is a rotating electromagnetic field is set up around an immersion nozzle to induce a swirling flow in it by Lorentz force. New types of swirling flow electromagnetic generator are proposed and the effects of the structure of the generator, the coil current intensity and frequency on the magnetic field and on the flow field in the immersion nozzle are numerically analyzed.
High Polaried Transmission Effects for Double-Layer Metallic Grating Films on GaN Substrate
Authors: Cao Bing , Zhang Gui Ju , Han Qin , Wang Chin Hua , Wang Jian Feng , Xu Ke
Published: July 2011

Highly polarized light transmission from GaN based light emitting diode is proposed using a double-layer metallic grating film and a dielectric transition layer. TM mode transmission and the polarized extinction ratio (ER) are calculated using commercial software, based on a full vector implementation of Rigorous Coupled Wave Analysis (RCWA) algorithm. Such a thin-film double-layer grating with subwavelength metallic stripes are designed and simulated by perfect parameters of period, thickness and filling factor for achieving good polarization properties. It is found that TM transmission and ER are almost stable and flat under different slit arrays of the double-layer grating. The polarized structure shows larger width of incident wavelength with a transition layer of a low refractive index than that of a high refractive index, but higher TM transmission and ER can be obtained for low refractive index transition layer. Flat sensitivity and high transmission of the TM mode on the double-layer metal grating thickness have been achieved. Up to 100nm range of the grating height can be employed to achieve TM transmission more than 92% while ER> 20dB. The results provide guidance in designing, optimizing and fabricating the integrated GaN-based and polarized photonic devices.
Effect of Thermomechanical Parameters on the Microstructure and Retained Austenite Characteristics in a Hot-Rolled TRIP Steel
Authors: Yin Yun Yang , Fang Fang , Chen Wei , Fu Yong Tao
Published: July 2011

The influence of thermomechanical parameters on the microstructure and retained austenite characteristics in a hot rolled Al-Si-Mn transformation induced plasticity (TRIP) steel based on dynamic transformation of undercooled austenite was investigated, in an effort to produce a desired microstructure and better control retained content. The results show that strain rate had a minor effect on the microstructure, but the volume fraction of retained austenite decreased with increasing strain rate. Decreasing coiling temperature caused a decrease in volume fraction of retained austenite and decrease in the size of bainitic ferrite platelets. Increasing the isothermal holding time during bainite treatment, the volume fraction of retained austenite first gradually increased then decreased. Moreover, The deformation of undercooled austenite not only can influenc the transformation of bainite, but also can refine the grain size of bainite, increase the chemical and mechanical stabilization of retained austenite.
Analysis of the Dry Mortar Produced with Iron Tailings
Authors: Liu Wen Yong , Yang Peng , Zhang Yong , An Yong Ye
Published: July 2011

This essay is the subject of national eleventh five support schemes: The analysis of key technology on emission reduction and comprehension utilization of solid waste from large iron ore mine (Number:2008BAB32B14). The purpose of this test is to replace natural sand with the same amount of iron tailings and find a new technology method to utilize solid waste, iron tailings, efficiently and valuably. Pre-determined cement, fly ash and cellulose ether are reasonable, which guaranteed the expected results of iron tailings instead of natural sand test .The proportion of iron tailings to replace natural sand is 0, 30%, 50%, 80%, 100%. Proportion design of M5, M7.5, M10, M15, M20 iron tailings dry mortar is determined by preliminary test. Respectively test water consumption, consistency and folding strength and compressive strength in 3d, 7d and 28d. Experiment results showed that the cementing material, PO42.5 cement made in Heng-sheng-ran Building Material Technology Co., Ltd. Beijing, has a good effect on smaller solid particles of iron tailings. After analyzing test data result, according to the provisions of “Specification for mix proportion design of masonry mortar” (JGJ 98-2000), In accordance with the principles of maximum using iron tailings and higher strength in 28d, recommended proportion of M5, M7.5, M10, M15, M20 iron tailings dry mortar has been determined. The test result will be used by actual production test.
Study on Spheroidization of Tungsten Powders by RF Plasma Processing
Authors: Sheng Yan Wei , Hao Jun Jie , Guo Zhi Meng
Published: July 2011

Spherical tungsten powders were synthesized by (RF) argon plasma with irregular tungsten powders in this paper. The microstructure and crystallographic phases of the synthesized powders were characterized using scanning electron microscopy (SEM) and X-ray diffractometry (XRD). The results showed that fine spherical powder composed of pure tungsten phase with favorable dispersity and its surface becomes smooth. The spheroidization efficiency of synthesized powders was almost 100 %, and the particle size distribution became narrower after spheroidization treatment. The spheroidization efficiency of the sample decreases gradually as increasing of the feeding rate. The RF plasma spheroidization of tungsten powder is an ideal route synthesis of well- spherical metallic tungsten powders which is widely used in thermal spraying and metal injection moulding process.
Microwave Assisted Synthesis of ZnO Calthrop-Like Nanostructures in Ionic-Liquid
Authors: Zheng Ju Gong , Yang Ting
Published: July 2011

ZnO Calthrop-like framework have been synthesized via a microwave assisted way by thermal decomposition of precursors in the ionic liquid 1-butyl-3-ethyl imidazolium tetrafluoroborate ([Beim]BF4) aqueous solution. The structure of [Beim]BF4were analyzed by means of IR and 1HNMR, The as-samples were characterized by XRD, SEM and UV techniques. The results showed that the as-prepared ZnO have wurtzite structure. nanorods have a diameter of 50 nm to100 nm and lengths of about 3 μm , and the ionic liquid [Beim]BF4can not only act as a reaction medium but also modify ZnO nanorods in the reaction. The growth mechanics of ZnO nano-structure was preliminary studied.
The Effect of Carbon Nanotubes on the Tribological Behaviors of PEEK Composites
Authors: Nie W.Z.
Published: July 2011

In this work, carbon nanotubes(CNT) filled polyetheretherketone (PEEK), with CNT contents ranging from 1 to 5 vol.%, were compounded by a ball milling process performed under room temperature. Nanocomposites were prepared through compression molding as-milled CNT/PEEK mixtures without further melt mixing. The incorporation of CNT leads to a significant improvement in material stiffness and a decrease in material ductility. The wear resistance of PEEK is significantly improved after incorporating CNT and at a rather low CNT loading, i.e. 5 vol.%, the composite presents the optimum wear resistance.
Dielectric Properties of Carbon-Materials-Filled Composites Characterized by Terahertz Time-Domain Spectroscopy
Authors: Chen Xi Liang , Chen Xin , Li Dang Sheng , Zhu Zhi Yong
Published: July 2011

The optical properties of composites, formed by filling the high density polyethylene (HDPE) with carbon black (CB), multi-walled carbon nanotubes (MWNTs) and fullerene (C60), respectively, in the frequence region from 0.3 to 2.0 terahertz (THz) were characterized with THz time-domain spectroscopy (THz-TDS). It is found that the optical parameters and the details of their variation with frequence and filler concentration are significantly different for different kinds of carbon materials. The MWNTs filled composites have the biggest absorption coefficient value, refractive index and real conductivity. The C60/HDPE composite shows very little changes in absorption and refractive index compared to that of the HDPE even at a filler-content of 12.3% in volume fraction. These phenomena are related to the special properties of the fillers as well as their particulate structures, such as aspect ratio, particle size, and aggregate structure, etc. The results are analyzed by using Cole-Cole theory of dipole relaxation under the assumption that carbon particles dispersed in the matrix behave like dipoles.
Alloying Element Nickel Influence on Microstructure and Properties of Weathering Steels
Authors: Liu Zhi Yong , He Xin Lai , Chen Ji Qing , Yang Shan Wu , Chen Bang Wen , Hu Min , Liang Wen
Published: July 2011

By testing the mechanical properties, microstructure observation, accelerated corrosion test, the effect of alloying element nickel on microstructure and properties of weathering steels was studied. The results showed that nickel content from 0 to 0.44%（mass percent）have little influence on microstructure and mechanical properties of weathering steels.The corrosion resistance enhanced with increasing nickel content, and nickel content of 0.11% or more had significant enfluence on corrosion resistant performance of weathering steels.