bluuebunny/crossref_metadata_2025 huggingface dataset:
Preparation of Activated Carbon Fiber Supported Nanoscale Fe0 for Simultaneous Adsorption and Dechlorination of Chloroform in Water
Authors: Wang Yuan Yuan , Huang Qian , Xian Qi Ming , Sun Cheng
Published: December 2011

Nanoscale zero-valent iron (NZVI) particles were supported onto activated carbon fiber (ACF) by impregnating ACF with ferrous sulfate followed by chemical reduction with NaBH4. A new kind of material ACF/NZVI with approximate 9.64% (wt%) iron was prepared, the structure of the prepared ACF/NZVI was characterized bySEM, XRD and BET. The average NZVI particles with the size of 8.1nm were well dispersed on the ACF. The activity of the prepared ACF/NZVI was evaluated for removing chloroform in water. When 5g/L of ACF/NZVI was added into water with 10 mg/L chloroform, more than 90% of chloroform in water was removed in 48h at pH7.0 and (25±2) ºС. The dechlorination and adsorption of chloroform on ACF/NZVI took place at the same time. The total Chloroform removal by ACF/NZVI was 53.1% after 48h. Consequently, ACF/NZVI exhibits the potential of simultaneous adsorption and dechlorination for chlorinated organic contaminants in water.
Influence of Citric Acid and Calcination Temperature on Microstructure of the Nano Precursors of La-Mg Hydrogen Storage Alloy
Authors: Wang Da Hui , Xia Ji Hong , Zhang Sha , Xia Yuan
Published: December 2011

The nano precursors of La-Mg hydrogen storage alloy have been prepared using citric acid, lanthanum nitrate and magnesium nitrate by so-gel technology. The effect of citric acid and calcination temperature on microstructure of the nano precursors of La-Mg hydrogen storage alloy have been studied by Infrared Radiation (IR), thermogravimetric and differential thermal analysis (TG/DTA), X-ray diffraction analyzer (XRD) and Transmission electron microscopy (TEM). IR results indicate the molar ratio of citric acid to metal cations increases from 1 to 1.3, the amount of citrate increases correspondingly, when the molar ration increases to 1.6, the amount of citrate goes up to maximum. The most appropriate amount of citric acid is 1.6 times that of the metal cations. In addition, the amount of citric acid have little influence on size of grains. XRD and TG/DTA results show that with increase of calcination temperature the amount of impurity phase, La(OH)3, decreases markedly. Formation of La2O3and MgO two-phase mixture occurred at 950°C. TEM results reveal that the morphology of the particles is almost flake with the size of ~50nm at 950°C and La, Mg, O three elements are observed in each flake.
Controlled Crystallization Synthesis of Porous FePO4·3H2O Micro-Spheres for Fabricating High Performance LiFePO4/C Cathode Materials
Authors: Zhang Wen Kui , Zeng Hui Juan , Xia Yang , Qian Ling Chao , Zhao Bin , Huang Hui , Gan Yong Ping , Tao Xin Yong
Published: December 2011

Amorphous porous FePO4·3H2O micro-spheres were synthesized via a controlled crystallization method. These micro-spheres have a particle size distribution from 10 to 28 μm. There are larger numbers of pores on the surface of FePO4·3H2O microspheres, which are important to synthesize high performance LiFePO4 cathode materials for the application of lithium ion battery. The electrochemical properties of the LiFePO4/C electrode, preparing by using the above porous spherical FePO4·3H2O particles, were measured. The electrochemical results show that the obtained LiFePO4/C has a high initial discharge specific capacity of 141.4 mAhg-1 and good cycling performance at 0.5 C. The microstructural and electrochemical analyses indicate that this porous spherical FePO4·3H2O is a fascinating precursor for preparing LiFePO4/C cathode materials.
Study on a Cd-Fe Redox Flow Battery in a Sulphuric Acid Electrolyte
Authors: Cheng Jie , Zhang Hui Min , Wen Yue Hua , Cao Gao Ping , Yang Yu Sheng
Published: December 2011

A Cd-Fe redox flow battery is proposed, in which CdSO4-H2SO4 aqueous solution is used as negative electrolyte, FeSO4-Fe2(SO4)3-H2SO4 aqueous solution is used as positive electrolyte, copper is used as negative electrode, carbon felt is used as positive electrode and proton exchange membrane is used as separator. Fe2+ is oxidized to Fe3+ at positive electrode and the Cd2+ is reduced to cadmium and electroplated onto the negative electrode during charge. The reverse occurs during discharge. An average discharge cell voltage of about 0.99V at 10mA/cm2 and an average energy efficiency of about 70.8% are obtained.
Effect of Pretreatment Process on Thermal Oxidation of Biomedical Grade Cobalt Based Alloy
Authors: Izman S. , Hassan M. A. , Kadir Mohammed Rafiq Abdul , Abdullah M.R. , Anwar Mahmood , Shah A. , Daud R.
Published: December 2011

Wear on Co-Cr-Mo biomedical implants is still a major issue especially for applications in articulation joints like in total ankle, knee and hip arthroplasty. Generation of excessive wear particles can coagulate in body tissues which later cause inflammation, bone loss and necrosis. Modification of implant surfaces is a common technique for increasing the hardness and thus minimizing these effects. In this study, thermal oxidation method was carried out on the Co-Cr-Mo to investigate the effects of different pretreatment processes and surface roughness on the hardness of oxide layer formed. Prior to oxidation process, all samples were annealed and pickled to remove residual stress and oxide scales respectively. The oxidation process was done inside furnace under atmospheric condition for 3 hours at 1160 °C. The metallic compositions, surface morphology and hardness of the oxide layer formed on the substrate were verified using X-ray diffraction (XRD), scanning electron microscope and micro-Vickers hardness analysis respectively. It is found that mechanical pretreatment provides oxide/carbide layer with higher hardness than chemical pretreatment method. It is believed that remnants of polishing diamond pastes trapped in roughness valleys react with metal matrix and later transform into carbides during oxidation process. In contrast, initial surface roughness of the substrate has no significant effect on the hardness of oxide/carbide layer.
Research on Compound and the Best Proportion of Phase Change Materials Using in Clothes
Authors: Chen Rou Xi , Sun Yu Chai
Published: December 2011

The desired phase-transition temperature and enthalpy of phase change materials are different in different application fields. When the composite way is reasonable, the phase-transition temperature and enthalpy of phase change can satisfy the demand of PCMs using in clothes. Based on The theory of eutectic system and the Schroeder Formula, the lowest eutectic point was computed by using MATLAB software in this paper, and then the enthalpy of phase change was also compared in order to get the best proportion of PCMs.
Deformation Behavior of Porous Ti-6Al-4V Alloy Samples Fabricated by Hot Isostatic Pressing
Authors: Xue Yong , Lang Li Hui , Bu Guo Liang , Li Li
Published: December 2011

In the present paper, hot uniaxial compression at elevated temperatures on the samples which had been hot isostatically pressed to 70%-100% relative densities was carried out to investigate the deformation behaviours of porous Ti-6Al-4V alloy. The results show that the flow stress and densification of Ti-6Al-4V alloy have a greater sensitivity on the deformation temperature and strain rate. The flow stress will increase as strain rate increases at the same temperature and the increasing of deformation temperature can lead to a decline in the flow stress at a specific rate. As the deformation temperature rises or the strain rate decreases, the relative density of compressed samples are higher. Moreover, the initial density affects the thermal deformation of powder compact to a certain extent. At the same strain, the greater the initial relative density of Ti-6Al-4V alloy is, the greater the flow stress will be. The flow stress sensitivity to relative density is much less than that to the temperature and strain rate. In addition, the higher the deformation temperature is, the more sufficient the process of alloy spheroidization will be. As the deformation rate decrease, the lamellar organization in the titanium alloy will convert into the equiaxed grains. The lower the deformation rate is, the more obvious the phenomenon of alloy globalization will be. There is not significant transition of the widmanstatten structure in the sample compressed for 2mm. When the sample was compressed for 5.6mm, a few equiaxed grains occurred. When the sample was compressed for 7mm, a large number of equiaxed grain occurred.
Electrode Material Effect on Electrical Discharge Machining PcBN Cutting Tool Processing
Authors: Jia Yun Hai
Published: December 2011

The electrode material is playing the very important role in the electrical discharge machining. Two kinds of electrode materials common used in EDM are compared and analyses similarities and differences in structure and physical characteristics. Combined with PcBN tool machining tests, from the electric discharge machining efficiency, electrode wear, tool surface quality, tool surface degenerating layer, machining results are in analysis and comparison, and then different electrode materials machining technics in electrical discharge machining process are summarized. Through the cutting tool electric discharge machining experiments, we can know that the graphite electrode easy to take shape, suits in the complex edge's cutting tool electric discharge machining, under the same electric discharge machining parameter condition, its processing efficiency must be higher than the copper electrode, but the electrode loses, the cutting tool surface quality and affect layer thickness are to be worse than the copper electrode.
Finite Element Analysis of β-Titanium during Equal Channel Angular Extrusion
Authors: Si Jia Yong , Hu Ze Hao , Zhong Li Ping
Published: December 2011

The finite element analysis was applied to evaluate the respective influences of die geometry and process conditions on plastic strain distribution for β-titanium (Ti-13V11Cr3Al) during the equal channel angular extrusion. It was found that optimum ECAE die geometry is strongly material dependent. Optimal strain homogeneity in the Ti-13V11Cr3Al alloy may be achieved at r (inner radius) =5mm, R (outer radius) =3mm. The equivalent plastic strain increases with increasing friction coefficient. And the better homogeneity of the equivalent plastic strain distribution can be achieved when m=0.1. The faster is the ram speed, the lower is the homogeneity of the equivalent plastic strain distribution. The back-pressure can increase the strain level across the workpiece and prevent the problem of surface cracking induced by tensile stresses. The distribution of the plastic strain is not temperature sensitive between 400°C and 600°C.
Study on the Pretightening Assembly Moving Beam of Open-Die Forging Hydraulic Press
Authors: Gu Rui Jie , Yang He , Zhang Ying Jie , Fang Zhi Yuan , Fan Yu Lin , Feng Dong Xiao
Published: December 2011

The FE model of the pretightening assembly moving beam of open-die forging hydraulic press is built with FE simulation software ABAQUS in the study. With the FE model, the force status of pretightening assembly moving beam is studied. Then the pretightening force of assembly moving beam is further studied and the computing method of pretightening force is given. The main achievements of the study include: Under pretightening, the stress of main moving beam is very low and that of guild sleeves is also lower than the allowable stress. Under center loading, the stress of the center field of main moving beam is higher and that of guild sleeves is almost same to that of pretightening. Under eccentric loading, the stress of same deviation field of main moving beam is higher and the effect of pretightening force on the stress of main moving beam is very small. The stress distribution of guild sleeves with different pretightening force is same and the effect of pretightening force on its strength is very low. The pretightening force of tension rod can be computed with the force of press, the allowable eccentric value of the workpiece, the distance between up guild section and down guild section of guild sleeve and the quantity of tension rods. The results of the study are very useful to design and install the pretightening assembly moving beam of open-die forging hydraulic press.
Behavior Engineering for the Analysis and Verification of Processes
Authors: Tuffley David , Wen Lian
Published: December 2011

Engineering in general is a process-intensive domain. Processes and process models underpin the activities of every Engineering discipline, ensuring consistent outputs by sequencing the right activities in the correct order. Acknowledging the importance of process models, there is a clear need for effective methods for verifying such models to ensure efficiency and correctness. This paper introduces a new formal methodology for the analysis and verification of processes,Behavior Engineering(BE) [1]. BE has proven very effective when applied to the development of process models. In this example, the discipline is Software Engineering, yet it is argued that the approach can be applied to any process or set of processes from Chemical, Materials and Metallurgical Engineering.
Simulation on Temperature and Residual Stress Field of Laser-MIG Hybrid Welding of A6N01-T5 Alloy
Authors: Li Da , Ji Hua , Liu Yan , Gou Guo Qing , Chen Hui , Liu Jin Bo , Meng Li Chun
Published: December 2011

MIG welding and laser-MIG hybrid welding have been widely used to joint aluminum alloy in recent years. Residual stress and heat cycling of MIG welding and laser-MIG hybrid welding are analyzed by SYSWELD software. The results show that the peak values of the stress in hybrid welding is 30~50% less than the results in the MIG welded joints.
First-Principles Study on Structure and Stability of YAP Crystal
Authors: Song Qing Gong , Liu Li Wei , Wang Yan Bo , Zhao Hui , Yan Hui Yu , Chen Yi Fei
Published: December 2011

The geometry optimization, formation energy, Mulliken populations, and density of states of YAP (YAlO3) crystal are studied by using first-principles method based on density functional theory. The optimal lattice parameters of YAP crystal are in good accordance with experimental results reported. The calculated formation energy (-3.73eV) indicates the excellent structural stability of YAP crystal. The obtained Mulliken charge populations of O, Al and Y atoms and their deviations from the formal ones, as well as overlap populations show YAP crystal is a mixed bond material with stronger ionic and weaker covalent bonds, which is attributed to the hybridization of atomic orbitals. The comprehensive effect of various interactions in the system makes YAP crystal more stable.
Study on the Range of Freeze-Thaw of Surrounding Rock from a Cold-Region Tunnel and the Effects of Insulation Material
Authors: Qi Peng , Zhang Jing , Mei Zhi Rong , Wu Yue Xiu
Published: December 2011

A mathematical models for the coupled problem is established by considering heat and mass transfer and phase change for rock mass at low temperature, according to the theory of heat and mass transfer for porous media. It is considered of the influences of fluid transfer on the heat conduction and the temperature gradient on the seepage. By adopting the finite element method, the numerical simulation is done to study the range of frost-thaw of surrounding rock and the effects of insulation material in cold regions, which analysis the influence of tunnel depth and surrounding rock class on the range of frost-thaw, the change law of the frost-thaw area of different insulation material and the relationship between the frost-thaw area and the thickness of insulation material.
The Processing, Microstructure and Mechanical Properties of Low Alloy Wear Resistance Steels
Authors: Wang Xue Min , Li Pei Zhu
Published: December 2011

With the aid of optical microscope, transmission electron microscope, scanning electron microscope, the processing and chemical composition on the microstructure and mechanical properties of low alloy wear resistance steels have been investigated. The results show that by multi-alloying design and TMCP processing the low alloy wear resistance steels has good synthetic properties. The lath martensite, multi phase microstructure composed of bainite and retained austenite film could be obtained after direct quenching. The lath martensite with retained austenite shows better wear resistance than bainite. Under the two bodies abrasive wear condition the characteristics of worn surface reveals that the main wear mechanism is micro-cutting.
Optimisation of Manufacturing Conditions of Carbon Fibre Reinforced Polyetherketoneketone (PEKK) Composite
Authors: Hou Meng , De Weger David
Published: December 2011

The effects of different processing conditions (pressure, holding time and temperature) on the impregnation/consolidation quality of CF/PEKK composite were investigated using compression molding process. Microscopic investigation of cross-sections, density measurements and flexural mechanical properties were used to examine the quality of impregnation and consolidation. A qualitative model to describe the impregnation and consolidation process of this material was developed. The model predicts the variations of void content during consolidation as well as the holding time, moulding temperature and pressure required to reach full consolidation. Good agreement between theoretical predictions and experimental data was achieved. Optimum processing conditions can be determined based on selected void content.
Microstructure Modeling for Prediction of Thermal Expansion Coefficient of Plain Weave C/SiC Considering Manufacturing Porosities
Authors: Lv Sheng Li , Zeng Qing Na , Yao Lei Jiang , Tong Xiao Yan
Published: December 2011

The aim of this paper is to propose a microstructure modeling for prediction of thermal conductivity of plain weave C/SiC fibre bundles considering manufacturing flaws. Utilizing photomicrographs taken by scanning electron microscope (SEM), we established an accurate sub representative volume element (sub-RVE) model for carbon fiber bundles and RVE for the plain weave C/SiC composite with consideration of four classes of manufacturing porosity. The thermal expansion coefficient of carbon fibre bundles on axial and transverse coefficient of thermal expansion is calculated, respectively. Based on which thermal expansion coefficient of plain weave C/SiC is obtained with the value of 2.71×10-6 in-plain, which has a good correlation with experimental value. The influences of different manufacturing flaws on material’s thermal expansion coefficient are studied. The study shows that as the matrix porosity or crack volume fraction is increasing, thermal expansion coefficient of plain weave C/SiC is decreasing correspondingly while the speed gradually slows.
Performance of Polypropylene Composites Filled by Calcium Carbonate Whiskers
Authors: Sun Qiu Ju , Zhao Gui Zhen , Xin Shi Gang , Wu Shi Wei , Lu Jie , Jiang Zhong Li , Sun Ming He , Li Wu
Published: December 2011

Calcium carbonate (CaCO3) whiskers were firstly treated by sodium stearate, and then blended with polypropylene (PP) to prepare the composites by a closely intermeshing co-rotating twin-screw extruder at 200°C. The performance of the composites, such as thermal behavior, microstructure and mechanical properties, were analyzed with differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), X-ray diffraction (XRD), scanning electron microscopy (SEM) and mechanical testing. The results showed that CaCO3 whisker influenced the crystalline behavior of PP phase in the blends because of its intervening. Moreover, thermo-decomposing temperature, tensile and bending strengths of the blends all increased with increasing whisker content. CaCO3 whiskers had good reinforcing and toughening effects on PP.
Influence of Dispersant on the Dispersion Stability of Nano-CoFe2O4 Refrigeration Oil
Authors: Li Guan Nan , Xing Mei Bo , Wang Rui Xiang
Published: December 2011

Abstract. Adding dispersants like surfactants and polymers to modify nanoparticles surface is an effective way to enhance the dispersion stability of nanoparticles in refrigeration oil. In this paper, many groups of nano-CoFe2O4refrigeration oil were prepared. In order to obtain the most effective kind of dispersant and the optimum additive amount, sedimentation observation method was employed for evaluation of the dispersion stability of CoFe2O4nanoparticles in 3GS mineral lubricant. The spectral behavior of the surface modified nano-CoFe2O4was studied by Fourier transform infrared (FT-IR) spectrometer. It was revealed that the optimized mass ratio between nano-CoFe2O4and dispersant ratio is 2 to 5; a relatively appropriate dispersant for nano-CoFe2O4would be Tween40, Tween60, Span80, Span80; Tween60 was the best. It was also illustrated in the infrared spectrum that nano-CoFe2O4particles surface modified by Tween60 was connected by organic groups in Tween60. Thus, the particles changed from hydrophilic to lipophilic and performed good dispersity and high stability when dispersed in mineral refrigeration oil.
Effect of Sintering Temperature and Particle Size on Porous SiC/Si3N4 Composite Ceramics
Authors: Wang Shuo , Li Jun , Yuan Wen Jie , Zhu Hong Xi , Deng Cheng Ji
Published: December 2011

Porous SiC/Si3N4 composite ceramic was prepared at different temperatures by pressureless using SiC and Si3N4 as raw materials. The effects of sintering temperature and different particle size of SiC on porosity SiC/Si3N4 composite ceramic were investigated. The phases, microstructure and mechanical property were characterized by XRD, SEM, and compressive tests respectively. The results indicate that the increase of sintering temperature is in favor of the formation of β-Si3N4 crystal phase, the porosity and the compression strengthof porous SiC/Si3N4 composite ; The porosity of Si3N4/SiC block which contain particle graded higher than single particle size, but weaker compression strength.
An Experimental-Numerical Approach of the Metallic Insert in CFRP/Honeycomb Sandwich Structures under Normal Tensile Load
Authors: Bunyawanichakul Phacharaporn , Kumsantia Patinya , Castanié Bruno
Published: December 2011

Sandwich structures are widely used in the aerospace field, also for primary parts. However, due to the low strength of core properties, the failure behavior under high stress concentration such as joining position is hard to evaluate. This study is, at present, a key task to enable future exploitation of the joint for structural sandwich consisted of Carbon Fiber Reinforced Polymer (CFRP) face and a Honeycomb core made of phenolic impregnated NomexTM paper. Previous experimental investigations provided the failure mechanism of sandwich plates with hard points in the form of inserts, and special attention is focused on the problem of sandwich panels with inserts of the fully potted types. Numerical simulations are achieved in this work with good correlation based on experimental test.
Hydrothermal Synthesis of Neodymium Orthophosphate with Controlled Structure and Morphology
Authors: Bao Jin Rong , Zhu Xiao Wei , Yu Ran Bo , Zhang Jia Yun , Xing Xian Ran
Published: December 2011

NdPO4•nH2O nanorods with a pure hexagonal and monoclinic phase were controlled synthesized through a hydrothermal route at low temperature. By simply increasing the molar ratio of PO4/Nd, pure monoclinic NdPO4can be obtained at lower temperature of 180 °C. Furthermore, NdPO4•nH2O nanorods can be assembled into flower- or bundle-shape. The reactant molar ratio played key roles in the formation of the products with different morphologies and structures. The possible formation mechanism for NdPO4 nanorods with different morphologies and structures was discussed. In addition, low-cost preparation of NdPO4 nanorods could be achieved through cycling use of phosphoric acid. Furthermore, this synthesis strategy will open a novel approach to rare earth phosphates with multiple structures.
Preparation and Microstructure of Al-Intercalated Vermiculite
Authors: Wang Chun Feng , Zhou Fei , Gu Hua Zhi , Zhu Hong Xi , Li Ya Wei
Published: December 2011

Crude vermiculite is used as raw materials, heat-treated for activation, leached with a complexing acid, exchanged with sodium solution, following contacted with polyhydroxyl aluminium solution. The Al-intercalated vermiculites are prepared by ion exchange. The phase and microstructure of the composite material are analyzed by means of XRD, TEM, TG-DSC, et al. The results reveal that the basal spacing of vermiculite expanded by intercalation of Al-species, and the interlayer of vermiculite inlaid with a large amount of nanometer Al-species particles.
Microwave Assisted Eletroless Copper Plating on Carbon Nanotubes
Authors: Wu Yong Qiang , Sun Si Kai
Published: December 2011

This paper firstly attempt to use microwave technology to assist carbon nanotubes by chemical copper plating, and comparated with the conventional method of copper plating, concluded the advantages of the microwave-assisted chemical deposition ,and try to develop a new technology of carbon nanotube composites.
Preparation of A14SiC4 by Solid-State Reaction
Authors: Liu Xiao Hong , Wang Hui , Zeng Ling Ke , Deng Cheng Ji
Published: December 2011

In this paper, A14SiC4 was synthesized by using flint, aluminum and carbon black as raw materials，and they mass ratio was 28:50:22. The samples were fired at 1500°C、1600°C and 1700°C in an argon atmosphere. The phase compositions were determined by X-ray diffraction (XRD), the microstructures were examined by scanning electron microscope (SEM) and the elemental and quantitative compositions were determined by the energy dispersive X-ray spectroscopy (EDX). The results showed that the flint reacted with the carbon black, and produced Al2O3 and SiC firstly; meanwhile Al4C3 as intermediate product formed by the reaction between Al and C. Then a certain Al4C3 reacted with SiC, and produced A14SiC4; most Al4C3 reacted with the Al2O3, and produced Al4O4C at higher temperature. Subsequently, the Al4O4C and the SiC reacted with carbon black, and produced A14SiC4. The formed quantity of A14SiC4 increased as the heating temperature was raised, and crystal structure was the flake structure of 1-2μm thickness and about 10μm length. The formation mechanism of A14SiC4 was also discussed.
Effect of Annealing Atmosphere on Structure and Properties in Chemically Deposited PbS Thin Films
Authors: Liu Feng , Deng Hong , Zhao Ai Ping , Deng Xue Ran
Published: December 2011

Large area (13mm*13mm) PbS thin films with (200) preferred orientation were prepared by chemical deposition. The optical properties of PbS films with annealing treatment in various forming gases with different ratio of nitrogen-oxygen (100ml/min of N2&O2(3:1), 100ml/min of N2&O2(2:1), 100ml/min of N2&O2(1:1), 50ml/min of O2) were deeply analyzed. X-ray diffraction (XRD), scanning electron microscope (SEM), high and low temperature test chamber and other test methods for photosensitivity were used to investigate the structure and photoelectric properties of PbS films. The results showed that with proper amount of oxidation (when nitrogen-oxygen ratio was 1:1), the impurity barrier tended to fully grow, impurity activation energy increased to 0.314eV, dark resistance reached up to 30.2MΩ, and the photoconductive sensitivity of PbS thin film under this process was about 4 times larger compared with air annealing. According to the analysis of XRD patterns and surface morphologies of films, it can be seen that nitrogen in this process was not only to prevent PbS thin films from excessive oxidation, but also inhibited the formation of surface defects and enhanced the stability of PbS device.
Magnetization Reversal in Ferromagnetic Thin Films
Authors: Sun Jia Li , Hu Jing Guo
Published: December 2011

The magnetization reversal mechanism of the magnetic films system with the different magnetic anisotropy, exchange coupling, interface coupling, etc. has been simulated by Monte-Carlo method. The results show that the decrease of magnetic anisotropy is in favor of motion of domain walls, but is not conducive to consistent rotation. The interface coupling of both the ferromagnetic film and the antiferromagnetic film are helpful to the motion of domain walls while the antiferromagnetic film coupling is the more effective. Meantime, the evolution of the microscopic magnetic domain structures has been inspected intuitively while the system is in the process of magnetization.
Synthesis, Characterization, Room Temperature Fluorescence and Phosphorescence Properties of Complex Gd(C5H8NO3)2(C3H5N2)2Cl3•3H2O
Authors: Wang Yan , Tian Da Ting , Yang Yi Xin
Published: December 2011

One solid coordination compound of Gadolinium chloride with N-acetyl-DL-alanine (C5H9NO3, Ac-Ala) and imidazole(C3H4N2,Im) has been prepared in absolute alcohol. The general formula Gd(C5H8NO3)2(C3H5N2)2Cl3•3H2O of these compounds was identified using the methods such as chemical and elemental analysis, FTIR spectra and UV spectra. The process of thermal decomposition was studied by TG-DTG. Room temperature fluorescence and phosphorescence measurement showed that the compound has good fluorescence and phosphorescence properties.
Influce Mechanism on Compressive Strength of Coke in Blast Furnace
Authors: Wang Xing Juan , Liu Ran , Li Hong , Zhu Li Guang , Fang Jue
Published: December 2011

Coke is the unique role of supporting material column in blast furnace high temperature region. Therefore the most important property is the high temperature compressive strength after reaction. This paper used decarburization electric furnace, electric mirrors, adjustable atmosphere high temperature compression testing machine and other equipments, study on the relationships between coke carbon loss rate and reactivity and size, the distribution rule between high temperature compressive strength and coke carbon loss rate. The study found that the carbon loss rate was affected by reactivity and size, in the same piece of coke, external rate of carbon loss higher than the internal loss, the surface carbon losses affect on coke strength is less, it make coke size decrease; carbon losses occur inside will not affect the size of coke, but it may affect the coke compressive strength seriously. The compressive strength can be divided into two parts: a constant and an amount proportional to carbon loss rate.
Recovery of Valuable Metals from Copper Slag by Hydrometallurgy
Authors: Chen Mao Sheng , Han Zi Rong , Wang Lei Zhi
Published: December 2011

A novel hydrometallurgical method was developed to recycle valuable metals of Si, Fe and Cu from copper slag. The leaching rates of 98%, 99% and 91% for SiO2, Fe and Cu, respectively, were obtained under optimized parameters: solid-to-liquid ratio is 1:10; concentration of hydrochloric acid is 35%; the reaction time is 2 hours and at 80-90°C.
Visualization of Flow-Field between the Flapper and Nozzle in a Hydraulic Servo-Valve
Authors: Mchenya Jacob M. , Zhang Sheng Zhuo , Li Song Jing
Published: December 2011

In order to understand the mechanism and get rid of the high-frequency self-excited noise in a hydraulic servo-valve, in this paper, the flow field distribution in the pilot stage of a hydraulic flapper-nozzle servo-valve is investigated. An assembly is prepared representing the construction and working principle of the flow field inside the pilot stage of a hydraulic flapper-nozzle servo-valve. A method of visualization is developed by taking videos for the flow field inside the transparent assembly with a high speed video camera. In this study, at different inlet pressure the high speed video camera was utilized for flow visualization together with computer-assisted image measurement. The shape of the jet flow, the cavitations and vortex flow inside the flow field can be visualized clearly. The proposed method enables to analyze the flow-field in the pilot stage of a hydraulic flapper-nozzle servo-valve by giving useful information for better design.
Generation and Emission Characteristics of Polycyclic Aromatic Hydrocarbons in Single Coal Coking Process
Authors: Shi Yan , Yue Zhi Xin
Published: December 2011

Polycyclic aromatic hydrocarbons (PAHs) is a kind of the typical persistent organic pollutants with their teratogenic, carcinogenetic, mutagenic. Coking production process has become one of the main sources of PAHs in the environment. For researching the generation and emission properties of PAHs in coking process, the writer studied the PAHs in single coal coking process through laboratory sampling and high-performance liquid chromatography analysis, observed and summarized the generation regularity and emission characteristics of PAHs in three kinds of single coal coking process, and provided the foundation data for the control of PAHs in coking process.
Numerical Calculation on Steel Coil during Annealing Process
Authors: Chen Chao , Ouyang De Gang , Song Zhong Hua , Chen Sheng
Published: December 2011

A two-dimensional mathematical model in cylindrical coordinate system was developed to simulate the temperature history of steel coil during annealing process. Based on finite difference method, the equations were calculated, and the temperature history of steel coil was obtained. Compared with experimental results, the calculation results are in good agreement with measurements. The temperature fields of steel coil at different time were analyzed, which can provide reference for optimizing of annealing process.
Mechanism of Precipitate Removal of Arsenic and Bismuth Impurities from Copper Electrolyte by Antimony
Authors: Xiao Fa Xin , Cao Dao , Mao Jian Wei , Shen Xiao Ni
Published: December 2011

This paper aims to discover the mechanism of removal of arsenic and bismuth from copper electrolyte under the function of antimony. The precipitate was obtained from a synthetic copper electrolyte containing 185g/L sulfuric acid, 45g/LCu2+, 10g/LAs, 0.5g/LBi and 1.2g/LSb. The structure, morphology and component of the precipitate are clarified by methods of chemical analysis, SEM, XRD, TEM and IR spectroscopy. The precipitate consists of 27.08% arsenic, 15.12% antimony, 12.08% bismuth. There are many irregular blocks, and dendritic particles on the surface.The characteristic bands in the IR spectra of the precipitate are O–H, As–OH, As–O, As–OX (X=As, Sb, Bi), Sb–OH and O–As–O. The precipitate is a mixture of microcrystalline of BiSb2O7, Bi12As2O23, SbAsO4and (Sb,As)2O3by XRD and electronic diffraction. The impurities of As, Sb and Bi are removed from copper electrolyte by antimony attributing to these precipitate.
Effects of Galvanic Interaction on Collectorless Flotation Behavior of Galena and Pyrite
Authors: Kang Duan , Chen Jian Hua
Published: December 2011

Galvanic interactions between sulfide minerals have significant effects on their electrochemistry and flotation behavior. The effects of galena and pyrite on their collectorless flotation behavior have been studied in this paper. The results showed that galvanic interaction between galena and pyrite would occur when they were mixed. In the galvanic-couple , pyrite forms a cathode due to the higher rest potential, and is reduced, which results in its floatability decreased; while galena forms a anode due to the lower rest potential, and is oxidized, which results in its floatability increased.
Research on the Role of Pre-Oxidation in the Separation of Cu-Pb in the Presence of Potassium Dichromate
Authors: Ke Bao Lin , Chen Jian Hua
Published: December 2011

It is the most effective method to use potassium dichromate to separate copper from lead when galena is oxidized. However, it needs long time to oxidize galena by potassium dichromate. The efficiency of five oxidants on potassium dichromate depressing ability to galena have been studied completely in this paper, and results suggest that separation of Cu-Pb can be carried out effectively in short time in the presence of potassium dichromate when galena is pre-oxidized by oxidants. Sodium hypochlorite is the best oxidant, and after the interaction of 15 min., the grade and the recovery of copper concentrate are 24.02% and 81.93% respectively, and the grade and the recovery of lead concentrate are 17.88% and 84.98% respectively.
Study on the New Technique for Micro-Particle Cassiterite of Dachang Tailings
Authors: Zhou De Yan , Wei Zong Wu , Zhang Chen Hu , Liao Xing Jin
Published: December 2011

The micro-particle cassiterite of Dachang tailings has been recovered by gravity concentration. The amplitude and frequency of strokes of table concentrator is optimized. The result of gravity concentration is that the grade of tin is 1.40%, and the recovery is 67.35%.Then, in the cassiterite reverse flotation, the new collector C08 was little used and the recovery of tin is achieved 90.05%
Studies on the Effects of Particle Size in Direct Reduction Roasting of Limonite Ores
Authors: Kou Jue , Sun Ti Chang , Li Yong Li , Cao Yun Ye
Published: December 2011

A series of direct reduction roasting - magnetic separation tests were carried out with refractory limonite ore in two different particle size compositions. The effect of particle size in the grade and recovery of direct reduced iron (DRI) at different roasting time, temperature and reductant dosages was investigated, and the mineralogical transformations of DRI obtained at different roasting time were analyzed using scanning electron microscopy (SEM-EDS). The results demonstrate that direct reduction roasting with limonite ore in large particle size (100% －20mm) was feasible, and the reducibility of limonite ore in large particle size increased with increasing reductant dosage and roasting time. The optimum reduction roasting - magnetic separation parameters of 100%－20mm limonite ore were proposed as the following: roasting at 1200°C for 120min with 40% reductant, and milling 30min followed by low intensity magnetic separation, which resulted in the DRI with TFe grade of 90.2% and recovery of 89.3%.
Analysis on the Stability of Yaoqiao Coalmine Ventilation System
Authors: Cheng Gen Yin , Sun Kai , Li Bo , Zhu Kai , Yao Hong Zhang , Zhang Jing Gang , Wang Wen Yong , Wang Fang
Published: December 2011

The stability of mine ventilation system has a significant impact on coalmine safety production. It is not only an important index of ventilation system quality, but also an important safety index of coalmine. The author made an analysis of ventilation system stability on the basis of test on Yaoqiao coalmine ventilation system resistance and indicated that the ventilation system of this coalmine existed some problems, which had an important meaning for enhancing the management of mine ventilation system and directing the normal, safe production.
Research on Geosynthetics in Tailings Dam Reinforcement
Authors: Shen Lou Yan , Zhou Ke Ping , Wei Zuo An , Chen Yu Long
Published: December 2011

With the tailings dam reinforcement project newly built in Yakou as the example and limit equilibrium horizontal slice method as the methodology, this paper has researched the feasibility of applying geosynthetics in fine tailings dam reinforcement. The results from limit equilibrium horizontal slice method show that the stability of reinforced tailings dam with geosynthetics increases by 14~17%; while results from numerical simulation method show that the principal stress vector direction and the principal displacement vector direction of the dam body can be changed to be favorable to the stabilization of dam by using geosynthetics to reinforce the tailings dam.
Research of Drilling Complexities in Dabei Belt of Tarim Basin
Authors: Hou Bing , Chen Mian , Jin Yan , Qiu Kang , Zhang Qing Yuan , Yang Pei
Published: December 2011

Kuche depression of Tarim Basin went through tectogenesis many times, due to the southward thrust compressional stress from Tianshan fold uplift, the geology condition of this area is extraordinarily complex, there are problems such as depth difference in geological horizons, abnormal pressure formations and irregular distribution of special lithologies, etc. All of these problems have brought even more difficulties in engineering design and construction. Accidents such as well leakage, drilling sticking and complex situations happened frequently. All of those have influenced the engineering progress seriously and lowered the actual effect of drilling. In order to resolve the problems and complex situations above, we did detailed researches on accidents in the Kuche piedmont belt of Tarim Basin and studied reasons for complex situations, and then we proposed engineering resolutions and evaluated them.
The Dynamic Finite Element Analysis of Shearer’s Running Gear Based on LS-DYNA
Authors: Tong Hai Long , Liu Zhong Hai , Yin Li , Jin Quan
Published: December 2011

Base on contact kinetics finite element theory, proceed secondary development of road wheel and pin mesh’s nonlinear dynamic contact analysis in LS-DYNA module, and carry out contrast of simulation analysis, achieved stress, strain and dynamic identities that caused by meshing impact in the whole meshing process, accord with practice, can instruct product practice design.
Study on Measuring Technique for Metal Tank’s Oil Temperature and it’s Level
Authors: Fei Yi Wei , Yang Hong Wei , Tong Li Ping , Sun Shi An
Published: December 2011

This paper designs real-time distributing measurement and monitoring system based on field bus for meeting the needs of testing and monitoring large-scale oil tanks. The system uses optical fiber sensor to collect the oil tank’s data, and has the advantages of the high precision, the high reliability, the strong anti-disturbed, and the avoiding of fire hidden trouble effectively, by the way of using the industrial Ethernet to achieve long-distance communication by RS-485, with a computer as controlling center to collect the data, and measures, monitors and manages oil tanks intelligently. And then the system is designed according to HART port protocol, as real-time testing and monitoring software to predict and manage automatically with advantages of fault diagnosis, routine maintenance, prediction of fire hidden trouble, and function of reliability, by relieving workload and good economical and social benefit.
Numerical Simulation of Flow-Induced Wall Shear Stress of a One Strand Tundish Design
Authors: Tian Zhi Bing , Jin Yan , Li Hong Yu
Published: December 2011

In this paper, the flow-induced wall shear stress on the wall of a one Strand tundish has been computed by a 3-D mathematical model. Different design parameters of the tundish such as HB(the height of the dam) and DB(the horizontal distance between the dam and the outlet of the tundish) are studied by analyzing the flow-induced wall shear stress. After a series of calculation, A modification in design parameters (DB and HB )of the tundish can reduce the wall shear stress, thus may help to improve the service life of the tundish.
Study of Magnetic Field Distribution of Carbon Nanotubes Resulting from Current Pass by Magnetic Force Microscopy
Authors: Kangarloo Haleh , Teymurzadeh Mehrdad , Rafizadeh Saeid
Published: December 2011

Recently carbon nanotubes (CNTs) are reported to be able to generate large magnetic field because of their nanometer-size-diameter[2]. The magnetic fields around CNTs current path are investigated by magnetic force microscopy (MFM). Under the consideration of the magnetic properties of magnetically coated tip of MFM, tip heights, current directions, and background magnetic field, etc., the magnetic field distribution are analyzed. The distribution of the magnetic field generated by the CNTs current is found to be asymmetric, and its distribution anomaly is found to be a kind of hysteresis effect of the MFM cantilever materials.
The Study of High Heat Resistance of Nano-Modified Silicone Pressure Sensitive Adhesives
Authors: Zhang Ming Yan , Wang Guan Hui , Yu Peng , Wang Yi
Published: December 2011

In this article, silicone pressure sensitive adhesives (PSAs) were modified with the Nano-SiO2 and nano-Al2O3. In order to prevent agglomerate, nano powder was dealt with silane coupling agent and then mixed into PSAs, both of the processes were under the action of ultrasonic. The results of test showed that all kinds of temperature index of modified PSAs were increased obviously, which means the high heat resistance of PSAs increased evidently. At the same time, its peel strength also increased, but the tack decreased. The effects of different nano powder are different, and the decomposition temperature of the nanocomposite raised 8.32% when the content of nano-SiO2 is 4.5wt%, while raised 14.02% when that of nano-Al2O3 is 1.5wt%, and the best compositive performances were obtained at this content of Nano-Al2O3.
Carbon Nanotubes for the Development of Glucose Biosensors Based on Gold Electrodeposition
Authors: Moghadam Firouzeh Karimi , Hamzehlooei Meysam
Published: December 2011

Superscript text
Subscript textOur study is to develop a general design of biosensors based on vertically aligned Carbon Nanotube (CNT) arrays. Glucose biosensor is selected as the model system to verify the design of biosensors. In the preliminary design, glucose oxidase (GOx) is attached to the walls of the porous alumina membrane by adsorption. Porous highly ordered anodized aluminum oxide (AAO) are used as templates. Deposited gold on both sides of template surfaces serve as a contact and prevent non-specific adhesion of GOx on the surface. In order to find out optimized thickness of gold coating, the redox reaction in([Fe(CN)6]3-/[Fe(CN)6]4-system is monitored by CV. Subsequently, enzymatic redox reaction in glucose solutions is also attempted by CV. We expect protein layers with GOx from a conductive network. To take advantage of the attractive properties of CNTs, the design of enzyme electrodes is modified by attaching CNT onto the sidewalls of AAO template nanopores and then immobilizing GOx to the sidewalls and tips of CNTs. Cobalt is used as a catalyst to fabricate CNTs. As a result, MWCNTs are fabricated inside the AAO templates by CCVD.
Adaptive Vibration Control for System with Friction Damping
Authors: Liu Yong , Wen Li Hua
Published: December 2011

The dynamic model of the single-degree-of–freedom (SDOF) mass-spring system with friction is established, based on the Lugre friction model. An observer-based model reference adaptive controller (MRAC) is proposed. By Lyapunov method, it is proved that the closed-loop system is asymptotically stable and the displacement as well as the velocity tracking errors can converge to zeros. Simulation work is carried out in both frequency and time domain. The results show that the proposed controller can greatly attenuate the response of the system significantly for both harmonic and random excitations.
Research on the Efficiency of Electronic Information Industry in China
Authors: Ran Jian Yu , Zhang Jian Sheng
Published: December 2011

The paper analysed the input-output efficiency of electronic information in 30 provinces of China with DEA model. The results show: the comprehensive technical efficiency values of 30 provinces are all low, with the average of 0.649, and the main reason leading to it is the low pure technical efficiency. Only the three provinces of Beijing, Zhejiang and Chongqing are in the high technical efficiency. Most provinces are in the stage of pay scale increasing, so growing scale and investment are the more efficient ways for the electronic information industry in china.
Application of Dynamic-Static Drainage Consolidation Method on a Silty Ground of Guangzhou
Authors: Zhang Li Juan , Li Zhang Ming
Published: December 2011

The treatment of a silty ground for petroleum product storage facilities in Guangzhou with dynamic-static drainage consolidation method which is based on based on combining the dynamic compaction method and the static consolidation is presented. The pore water pressure, settlement, field vane shear strength, bearing capacity through plate load tests have clearly shown that this method can significantly strengthen the silt ground within reasonable time frame. The soft ground has been improved under the dynamic and static forces and their residual effects.