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The Dissymmetry of Friction Stir Welding Joints and Va-riable Polarity Plasma Arc Welding Joints Study

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稀有金属材料与工程 2011年第S4期40卷 84-89页

作者： Chen Shujun,Wang Long,Yu Yang Beijing university of technology mechanical {3.,Beijing100022,china Beijing Univ Technol Mech Engn Beijing 100022 Peoples R China

2219 aluminum alloys welding joints were prepared by Friction stir welding (FSW) and Variable polarity plasma arc welding (VPPAW).The microstructure of joints was characterized by means of OM,SEM,and *** measurements was performed to differentiate the joint zones and to evaluate the symmetry level of the joints with the help of nano-indentation *** dissymmetry of microstructure and mechanical properties was found both in FSW joint and VPPAW *** dissymmetry in FSW joint can not be suppressed due to the nature of the mixing head,but the symmetry and satisfactory welding joint can be obtained by changing the working pattern of VPPAW.

关键词： FSW VPPAW nano-indentation experiment "Half-leaf" zone dissymmetry

A fusion algorithm for remote sensing images based on nonsubsampled pyramids and bidimensional empirical decomposition

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Science china(Technological Sciences) 2010年第S1期53卷 196-204页

作者： ZHANG XiaoDong 1,WANG WenBo 2,WANG DiFeng 3.& ZHANG Yu 4 1 State Key Laboratory of Information engineering in Surveying,Mapping and Remote Sensing,wuhan university,wuhan 43.079,china 2 college of Sciences,wuhan university of Science and technology,wuhan 43.065,china 3.tate Key Laboratory of Satellite Ocean Environment Dynamics,Second Institute of Oceanography,State Oceanic Administration,Hangzhou 3.0012,china 4 Spatial Information technology Application Research Institute,Changjiang River Scientific Research Institute,wuhan 43.010,china wuhan Univ State Key Lab Informat Engn Surveying Mapping & R Wuhan 430079 Peoples R China wuhan Univ Sci & Technol Coll Sci Wuhan 430065 Peoples R China State Ocean Adm Inst Oceanog 2 State Key Lab Satellite Ocean Environm Dynam Hangzhou 310012 Zhejiang Peoples R China Changjiang River Sci Res Inst Spatial Informat Technol Applicat Res Inst Wuhan 430010 Peoples R China

In order to improve the quality of remote sensing image fusion,a new method combining nonsubsampled Laplacian pyramid (NLP)and bidimensional empirical mode decomposition(BEMD)is ***,the high resolution panchromatic image (PAN)is decomposed using NLP until the approximate component and the low resolution multispectral image(MS)contain features with a similar ***,the approximation component and the MS are decomposed by BEMD,resulting in a number of bidimensional intrinsic mode functions(BIMF)and a residue *** instantaneous frequency is computed in 4 directions of the *** the positive or negative coefficients in the corresponding position,a weighted algorithm is designed for fusing the high frequency details using the instantaneous frequency and the coefficient absolute value of the BIMFs as fusion *** fused image is then obtained through inverse BEMD and *** results have illustrated the advantage of this method over the IHS,DWT andà-Trous wavelet in both spectral and spatial detail qualities.

关键词： bidimensional empirical mode decomposition nonsubsampled pyramid instantaneous frequency remote sensing image fusion

Performance analysis of a 2-stroke micro free-piston swing engine

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Petroleum Science 2009年第3期6卷 313-318页

作者： Zhang Shimin Guo Zhiping Wang Jinsong School of mechanical and Electronic engineering China University of Petroleum Beijing 102249 China college of mechanical engineering Inner Mongolia University of Technology Hohhot Inner Mongolia 010051 China Department of Precision Instrument and Mechanology Tsinghua University Beijing 100084 China

The micro free-piston swing engine （MFPSE） is a new structure, free-piston internal combustion engine. The dynamic model integrated MFPSE with a power generator and thermodynamic models in compression, power and scavenge processes based on the open thermodynamic systems were presented. A simulation was executed at given geometric parameters and initial conditions. The results manifest that the working principle of MFPSE is feasible.

关键词： Micro free-piston swing engine working principle performance simulation

Influence of the impounding process of the Three Gorges Reservoir up to water level 172.5m on water eutrophication in the Xiangxi Bay

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Science china(Technological Sciences) 2010年第4期53卷 1114-1125页

作者： YANG ZhengJian1,LIU DeFu1,JI DaoBin1,2 & XIAO ShangBin1,3.1 college of Civil & Hydroelectric engineering,china Three Gorges {3.,Yichang 443.02,china 2 School of Water Resources & Hydropower engineering,wuhan {3.,wuhan 43.072,china 3.Institute of Earth Environment,Chinese Academy of Sciences,Xi’an 710075,china 1. college of Civil & Hydroelectric engineering China Three Gorges University Yichang 443002 China2. School of Water Resources & Hydropower Engineering Wuhan University Wuhan 430072 China3. Institute of Earth Environment Chinese Academy of Sciences Xi’an 710075 China

The water level of the Three Gorges Reservoir(TGR) rose to 172.5 m in two stages from September to November,*** hydrodynamic parameters and water quality parameters(*** velocity,temperature,turbidity and nutrient content) had been continuously monitored to reveal the influence of the impounding process of the TGR on the water eutrophication in the Xiangxi Bay(XXB).The maximal daily rise of the water level of the TGR was about 2.3. *** water exchange between the mainstream(the Changjiang River) and the XXB of the TGR was enhanced by density current,and its main characteristics were a density-stratified flow in different *** water exchange reduced the differences of the water quality parameters(for example,temperature,turbidity,nutrient level,pH,etc.) between the mainstream and the XXB during the impounding ***,the water stability index in the mainstream remained small but it was lowered in the *** main causes included the dilution by water of lower concentration of the chlorophyll a(Chl.a) entering from the mainstream,the decline of the water stability,and the increase of suspended silt,which induced the Chl.a to decrease in the XXB during the impounding *** grade of the water eutrophication changed from middle eutrophic level to mesotrophic state in the ***,as available nutrients were imported into the XXB from the mainstream during the impounding process the risk of water eutrophication increases in the XXB in the future.

关键词： impounding density current eutrophication the Xiangxi Bay the Three Gorges Reservoir

DIMPLE FORMATION ON FRACTURE SURFACE OF STEEL 55SiMnMo

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Acta Metallurgica Sinica(English Letters) 1993年第2期6卷 140-143页

作者： LIANG Sizu LIANG Yaoneng LIU Zhengyi South china university of technology,Guangzhou,{3. Lecturer,Department of mechanical engineering No.2,South china university of technology,Guangzhou 510641,{3. South china Univ of technology Guangzhou China

The fracture surface of the normalized steel 55SiMnMo was observed,under tensile device at- tached on the SEM,to be of ductile dimple feature on the bainite which is composed of lath ferrite and austenite *** dimple is essentially nucleated in the *** the austenitic plastic deformation is remarkable during fracturing,the tear ridge of dimple is very sharp.

关键词： dimple plastic deformation ductile fracture steel 55SiMnMo

Influence of Formate on Bioactivity Material-thuringiensin Synthesized by Bacillus thuringiensis YBT-03.

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Journal of wuhan university of technology(Materials Science) 2008年第5期23卷 691-693页

作者：王志喻子牛 college of Bioengineering Hubei University of Technology State Key Laboratoy of Agricultural Microbiology National engineering Research Center for Microbial Posticides Huazhong Agricultural University

The biological method to synthesize thuringiensin and the influence of formate on thuringiensin biosynthesis were investigated. Addition of 1.00 g/L formate to growth medium of bacillus thuringiensis YBT-03. resulted in significant enhancements in productions of citrate, α -ketoglutarate, intracellular adenine and thuringiensin. These results demonstrate that added formate attends metabolism of cell, facilitates carbon metabolic flux in tricarboxylic acid cycle and hexose monophosphate pathway. As a carbon source, formate facilitates cell growth, increases glucose consumption and enhances the ability of cell to synthesis adenine analogues, and subsequently thuringiensin. Thuringiensin production rate significantly enhanced from 6.44 to 8.46 mg·g^-1 · h and transformation ratio from glucose to thuringiensin increased by 43.3.%.

关键词： bacillus thuringiensis precursor formate thuringiensin

Effects of binders on the performance of electric double-layer capacitors of carbon nanotube electrodes

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Progress in Natural Science:Materials International 2005年第5期15卷 453-457页

作者： LI Chensha1*, WANG Dazhi1, ZHANG Baoyou2, WANG Xiaofeng1, CAO Maosheng3. and LIANG Ji1(1. Department of mechanical engineering, Tsinghua university, Beijing 100084,{3. 2. Center for Analysis and Measurement, Harbin Institute of technology, Harbin 150001,{3. 3. School of Material Science and engineering, Tsinghua university, Beijing 100084,{3.) Department of mechanical engineering Tsinghua University Beijing 100084 China Center for Analysis and Measurement Harbin Institute of Technology Harbin 150001 China School of Material Science and engineering Tsinghua University Beijing 100084 China

Polarizable electrodes of electric double layer capacitor (EDLCs) were made from carbon nanotubes. Effects of different binders, which are phenolic resin (PF) and polytetrafluoroethylene (PTFE), on the properties of polarizable electrodes are studied. Results indicate that the microstructure, pore size distribution and specific capacitance of the electrodes with PTFE binder are superior to those electrodes with PF binder after carbonization. The suitable binder (PTFE) for carbon nanotubes electrodes is proposed.

关键词： carbon nanotubes electric double-layer capacitors phenolic resin polytetrafluoroethylene.

A MECHANICS MODEL FOR CIRCULAR FORM TOOL CUTTING

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中国有色金属学会会刊：英文版 1996年第2期6卷 86-90,94页

作者： Xia Wei Li Yuanyuan Zhou Zehua (Department of mechanical engineering,South china {3. of technology, Guangzhou 510641) S china UNIV TECHNOL DEPT MECH ENGNGUANGZHOU 510641PEOPLES R CHINA

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关键词： metal cutting mechanical medel circular form tcol

New Solution to Surface Temperature of Casting Slab Measurement Based on Preceded Reflector and Multi-Wavelength

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Journal of Iron and Steel Research International 2012年第8期19卷 12-16页

作者： LIU Jun1, MA Jiao-cheng2, YANG Feng3. XIAO Hui1, RAO Li-min1 (1. School of Nuclear engineering and technology, East china Institute of technology, Fuzhou 3.4000, Jiangxi, china 2. School of mechanical engineering and Automation, Northeastern university, Shenyang 110004, Liaoning, china 3. School of Civil and Environmental engineering, East china Institute of technology, Fuzhou 3.4000, Jiangxi, china) [a] School of Nuclear engineering and technology East China Institute of Technology Fuzhou 344000 Jiangxi China [b] School of mechanical engineering and Automation Northeastern University Shenyang 110004 Liaoning China [c] School of Civil and Environmental engineering East China Institute of Technology Fuzhou 344000 Jiangxi China

The surface temperature of casting slab is an important parameter in the metallurgy field. Because the surface emissivity is uncertain and also unknown, it is difficult to measure the slab surface temperature accurately. A method based on preceded reflector and multi-wavelength was put forward to deal with the difficulty in surface temperature measurement of casting slab. On the premise of preceded reflector and non-preceded reflector, the method establishes the radiation energy equations and works out the emissivity and temperature in the equations. Also, the multilayer modeling of casting slab surface and multiple reflection-absorption process modeling were built by Monte Carlo method. The temperature measuring method had been applied in the continuous casting field. In order to verify the measured result, the thermal imaging method was adopted when the slab surface emissivity was set by repeated tests. Finally, the measured and verified temperature curves keep a same tendency and the error of the values is lower than 5℃. The comparison result shows that the method can measure temperature accurately.

关键词： casting slab emissivity surface temperature preceded reflector multi-wavelength