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An MFC capable of regenerating the cathodic electron acceptor under sunlight

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中国科学：技术科学英文版 2010年第9期53卷 2489-2494页

作者： FU Qian,LI Jun,ZHU Xun,LIAO Qiang,YE DingDing & ZHANG Liang Institute of Engineering Thermophysics,chongqing University,chongqing 400030,China Institute of Engineering Thermophysics Chongqing University

A renewable MFC (microbial fuel cell) cathode was used in this study because the iodide ion could react with oxygen to generate triiodide under natural *** feasibility of the regeneration of triiodide ion under natural sunlight and the effect of the regenerated triiodide ion concentration on the MFC performance were *** results showed that the power density of the MFC using triiodide ion as cathodic electron acceptor was significantly higher than that of using ferricyanate,and that the iodide ion can be oxidized to triiodide ion by oxygen in air at the expense of natural *** addition,it was obvious from the experimental results that the MFC performance was improved with the increase of the triiodide concentration,indicating that the concentration of triiodide ion had a critical effect on the MFC *** linear sweep voltammetry (LSV) curves for the electro-reduction of triiodide ion on the carbon paper were obtained and the results suggested that the diffusion process of triiodide ions to cathode was the control factor for the MFC performance.

关键词： microbial fuel cell cathodic electron acceptor triiodide ion

Decomposition of the Coarse Primary Carbides in the M2 High Speed Steels Containing Silicon

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稀有金属材料与工程 2011年第S3期40卷 38-42页

作者： Wang Weiqing, Pan Fusheng, Tang Aitao, Liu Tingting, Liu Shengming, Luo Suqin chongqing University, chongqing 400030, China chongqing Univ Coll Mat Sci & Engn Chongqing 400030 Peoples R China

The carbides of high speed steels have a determinant influence on their properties, and the control of the carbides has been a hot topic in development of high speed steels. The decomposition of the coarse primary M2C carbide in the as-cast M2 high speed steels with Silicon addition and without Silicon addition was investigated by using optical microscope, scanning electron microscopy, energy dispersive spectroscopy and X-ray diffraction analysis. Both the M2 high speed steel and the M2-1Si steel were heated at 1000 and 1150 ℃, the soaking time were 15 min, 30 min, 1 h, 2 h and 4 h, respectively. The results showed that the decomposition of M2C carbides to M6C and MC carbides occurred during heating at 1000 ℃,the degree of the decomposition became obvious with the increase of heating time or addition of silicon. After the tested steels were heated at 1000 ℃ for 1 h, the primary M2C carbides in the M2-1Si steel had decomposed into M6C and MC completely, but the decomposition of the primary M2C carbides in the M2 steel was incomplete. Silicon addition was found to accelerate the decomposition of the coarse primary M2C carbides during heating and to inhibit the growth and coarseness of the decomposition products.

关键词： M2 high speed steels carbides silicon decomposition

Flow instability of buoyant-Marangoni convection in the LEC GaAs melt

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Science China(Technological Sciences) 2008年第4期51卷 397-406页

作者： CHEN ShuXian1 & LI MingWei2,3 1 Aviation Engineering Institute, Civil Aviation Flight University of China, Guanghan 618307, China 2 Institute of Power Engineering of chongqing University, chongqing 400030, China 3 Research Center of Biological Function Information and Instruments of chongqing University by Sec-ond-Term National 985 Project, chongqing University, chongqing 400030, China Aviation Engineering Institute Civil Aviation Flight University of China Guanghan 618307 China Institute of Power Engineering of chongqing University Chongqing 400030 China

Flow transitions and instabilities have significant effects on the quality of the crystals. The flow and heat transfer in the LEC GaAs melt are numerically studied by a time-dependent and three-dimensional turbulent flow model. The effects of the change of the buoyancy and Marangoni force on the flow state are analyzed by changing the temperature difference between the crystal and the crucible walls. The results show that the flow will transform from axisymmetric steady flow to non-axisymmetric oscillatory flow when the temperature difference exceeds the critical value, and that the mechanism of the transition is attributed to the Marangoni instability. The critical temperature differences for the flow transitions corresponding to different melt depth H are numerically predicted. Several important characteristics of the non-axisymmetric buoyant-Marangoni convection are numerically observed and compared with that of the non-axisymmetric mixed convection coupled with crystal rotation.

关键词： flow transition flow instability buoyant-Marangoni convection mixed convection LEC GaAs melt

Modeling of Stress Distribution During Strip Coiling Process

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Journal of Iron and Steel Research International 2012年第8期19卷 6-11页

作者： WANG Yong-qin, LI Li, YAN Xing-chun, LUO Yuan-xin, WU Liang (The State Key Laboratory of Mechanical Transmission, chongqing University, chongqing 400030, China) The State Key Laboratory of Mechanical Transmission Chongqing University Chongqing China

Many strip materials are coiled after rolling process. The stresses are imposed on the material wound on the automatically controlled collapse mandrel under the coiling tension. The coiling process can be described by three typical cases: winding without automatic adjustment, winding with automatic adjustment and after mandrel removal. A new model of equations for predicting the stresses during the strip coiling process is built by consideration of the three cases respectively. By solving the equations of different typical cases, the radial stresses and tangential stress of the layers of coil can be calculated. Also, the coiling parameters, such as strip thickness, coiling tension and necking critical pressure, affecting the coil performance are investigated. It is believed that the present model can be used for design and control of the automatically controlled collapse mandrel.

关键词： automatically controlled collapse mandrel coiling process critical pressure radial stress tangential stress

Inclined-cross Microstructure of Conch Shell

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Journal of Wuhan University of Technology(Materials Science) 2005年第B12期20卷 89-91页

作者：陈斌 Department of Engineering Mechanics Chongqing University Chongqing 400030 China

The microstructures of conch shell were observed with scanning electronic microscope （SEM）, and a kind of inclined-cross microstructure of aragonite sheets was found. The maximal pull-out force of the inclined-cross microstructure was analyzed based on its representative model and compared with that of a conventional 0 °- structure. The experimental result indicates that the maximal pull-out force of the inclined-cross microstructure is markedly larger than that of the 0°- structure.

关键词： conch shell inclined-cross structure pull-out force fracture toughness

Research on Integrated Green Supply Chain Management

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武汉理工大学学报 2006年第S1期28卷 325-329页

作者： DENG Lei,WANG Xu (College of Mechanical Engineering,chongqing University,chongqing 400030,China) College of Mechanical Engineering Chongqing UniversityChongqing 400030China

On the basis of the analyzing product life cycle and value chain management in green supply chain,integrated green supply chain is put forward and constructed which involve lean production,agile manufacturing and green supply chain. This integrated structure provides an effective method for resolving some questions such as cost,market,environment,etc. in enterprise. A case study is presented at the end of paper to demonstrate how integrated supply chain implemented successfully in enterprise.

关键词： green supply chain lean production agile manufacturing,leagile supply chain integration

Effect of Sr on microstructure and aging behavior of Mg-14Li alloys

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Progress in Natural Science:Materials International 2012年第2期22卷 160-168页

作者： Bin Jiang a,b,c,Ying Zeng b,Hengmei Yin a,b,Ruihong Li a,b,Fusheng Pan a,b a National Engineering Research Center for Magnesium Alloys,chongqing University,chongqing 400030,China b College of Materials Science and Engineering,chongqing University,chongqing 400030,China c New Materials Center,chongqing Academy of Science and Technology,chongqing 401123,China National Engineering Research Center for Magnesium Alloys Chongqing University College of Materials Science College of Engineering Chongqing University New Materials Center Chongqing Academy of Science and Technology

The as-cast and as-extruded Mg-14 wt%Li-xSr(x=0.14,0.19,0.39 wt%)alloys were,respectively,prepared through a simple alloying process and hot *** effects of Sr addition on microstructure and aging behavior of the Mg-14 wt%Li-xSr alloys were *** results indicated that b(Li)and Mg2Sr were the two primary phases in the microstructures of both as-cast and as-extruded Mg-14 wt%Li-xSr ***,with the increase of Sr content from 0.14 wt%to 0.39 wt%,the grain sizes of the as-cast and as-extruded Mg-14 wt%Li-xSr alloys markedly decreased from 5000 mm and 38 mm to 330 mm and 22 mm respectively,while no obvious changes of the micro-hardness and microstructure of the as-extruded alloys were observed during the aging treatment.

关键词： Magnesium-lithium alloys Microstructure Grain refinement Aging behavior

Stress distribution rule of roadway affected by overhead mining in gently inclined coal seams group

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中国有色金属学会会刊：英文版 2011年第S3期21卷 529-535页

作者： KANG Qin-rong1, 2, TANG Jian-xin1, 2, HU Hai1, 2, ZHANG Wei-zhong1, 3 1. College of Resource and Environmental Sciences, chongqing University, chongqing 400030, China 2. State Key Laboratory of Coal Mine Disaster Dynamics and Control, chongqing University, chongqing 400030, China 3. School of Safety Science and Administration, Zhongnan University of Economics and Law, Wuhan 430074, China College of Resource and Environmental Sciences Chongqing University Chongqing 400030 China State Key Laboratory of Coal Mine Disaster Dynamics and Control Chongqing University Chongqing 400030 China School of Safety Science and Administration Zhongnan University of Economics and Law Wuhan 430074 China

In light of the severe deformation and destruction of the district raise tunnel in the mining area at the northern part of the Lubanshan colliery, by the theoretic analysis and numerical simulation, both the mining stress distribution in seams group and the deformation and destruction mechanism of floor district raise were investigated. The results show that, at the maximum vertical distance of 40 m, the abutment stress has an influence on the recovery of 2# and 3# coal seam and 8# coal seam at distance of 30 m. As a result, the recovery of 8# is rather than those of 2# or 3# coal seam, which contributes to the deformation and destruction of the district raise surrounding rock. The major factors affecting the abutment stress include the mining depth, mining height, residual gob space, adjacent working faces and short spacing coal seam recovery.

关键词： coal seams group stress distribution district raise surrounding rock deformation and destruction abutment stress

High-Temperature Mechanical Properties of Shipbuilding Steel BC in Continuous Casting

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Journal of Iron and Steel Research International 2011年第S1期18卷 605-609页

作者： DONG Zhi-hua,CHEN Deng-fu,SONG Li-wei,HU Hui,YANG Xing-lei (College of Materials Science and Engineering,chongqing University,chongqing 400030,China) chongqing Univ Coll Mat Sci & Engn Chongqing 400030 Peoples R China

The mechanical property of shipbuilding steel BC has been studied by means of tensile test at various temperatures from 700 ℃ to 1000℃ with theGleeble-1500D thermo-mechanical *** results indicate that the yield strength and tensile strength of steel have an analogous change pattern as temperature decreasing,and the transition in variation rate of strength occurs at 800℃ in both of them;the hot ductility trough of steel BC is a temperature range from 725℃ to 800℃,while the best hot ductility ranges from 875℃ to 1000℃ with the ductility value over 80%.For the sake of understanding the fracture mechanism of the steel,fracture surface and microstructure of the specimens have been examined by scanning electron microscope and metalloscope *** results show that both the second phase particles and the pro-eutectoid ferrite surrounding the austenite boundaries play a significant role to the variation of hot ductility of steel ***,the research is important to the improvement and the further studies on the quality of steel during slab continuous casting process.

关键词： continuous casting slab mechanical property hot ductility microstructure