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Effects of Ca substitution and surface treatment on electrochemical performances of Ml_(1.0-x) Ca_xNi_(4.0) Co_(0.6) Al_(0.4) hydrogen storage alloy electrodes

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中国有色金属学会会刊：英文版 1999年第3期9卷 487-492页

作者： chen Weixiang(陈卫祥) 1. Qi Jianqin(祁建琴) 1. chen Changpin(陈长聘) 2 1. Department of Physics 2. Department of Materials Science and Engineering, Zhejiang University, Hangzhou 31.027, P. R. China 浙江大学物理系浙江杭州浙江大学材料科学与工程系浙江杭州

The influences of Ca substitution for Ml and surface treatment on electrochemical performances of Ml 1.0- x Ca x Ni 4.0 Co 0.6 Al 0.4 hydrogen storage alloy electrode were investigated. Ca substitution with x 0.2 could decrease the capacity. It was also found that Ca substitution deteriorates the electrocatalytic activity, high rate dischargeability and cycling durability of the alloy electrode. In order to improve these properties of Ml 1.0- x Ca x Ni 4.0 Co 0.6 Al 0.4 alloy electrode, the alloy was treated in 6 mol/L KOH+0.02 mol/L KBH 4 solution. The results showed that the surface treatment improves the electrochemical performances such as the electrocatalytic activity, high rate dischargeability and cycling durability of the alloy electrode. :The influences of Ca substitution for Ml and surface treatment on electrochemical performances of Ml 1.0- x Ca x Ni 4.0 Co 0.6 Al 0.4 hydrogen storage alloy electrode were investigated. Ca substitution with x 0.2 could decrease the capacity. It was also found that Ca substitution deteriorates the electrocatalytic activity, high rate dischargeability and cycling durability of the alloy electrode. In order to improve these properties of Ml 1.0- x Ca x Ni 4.0 Co 0.6 Al 0.4 alloy electrode, the alloy was treated in 6 mol/L KOH+0.02 mol/L KBH 4 solution. The results showed that the surface treatment improves the electrochemical performances such as the electrocatalytic activity, high rate dischargeability and cycling durability of the alloy electrode.

关键词： hydrogen storage alloy electrode Ca substitution surface modification

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Abnormal gradient microstructure in Cr_3C_2 based cemented carbide

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Journal of Central South University of Technology 2001年第4期8卷 224-227页

作者： ZHANG Li 1.chen Shu 2 (1. Powder Metallurgy Factory, Central South University, Changsha 41.083, China 2. Changsha Research Institute of Mining and Metallurgy, Changsha 41.01., China) Powder Metallurgy Factory Central South University Changsha China Changsha Research Institute of Mining and Metallurgy Changsha China

With OLYMPUS PMG3 metallograph, an abnormal three-layer gradient structure, i. e. coarse grain zone, binder enrichment zone and normal structure zone from surface to inner, was observed in Cr3C2 based cemented carbide. In the binder enrichment zone, three different shapes of anomalous coarse carbides were observed. It is shown that the transverse rupture strength can be raised remarkably, up 20.7%from the alloy with abnormal gradient structure by removing the abnormal gradient structure. The results suggested that the abnormal gradient structure in the surface, especially the anomalous coarse carbides in the binder enrichment zone is the main reason for the lower strength

关键词： Cr3C2 based cermet cemented carbide gradient structure microstructure

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Changes of infrared absorption wave number of aromatic-ring C=C bond of vitrinite and their significance

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Chinese Science Bulletin 1998年第12期43卷 1048-1050页

作者： XIAO Jianxin 1.and chen Shanqing 2 1. China University of Geosciences, Beijing 1.0083, China 2. Yichang Institute of Geology and Mineral Resources, Yichang 443003, China China University of Geosciences Beijing China Yichang Institute of Geology and Mineral Resources Yichang China

The humilith series of lignite, longflame coal, gas coal, fat coal, coking coal, lean coal, meagre coal and anthracite are measured by FIR1.00 infrared spectrophotometer. The variation curve between the infrared absorption wave number of aromaticring C--C bond of vitrinite and its reflectance values are gained, which shows the shift of infrared absorption wave number of aromaticring C--C bond of humic coals towards lower wave number with the increase of coalification. It is believed that the coal rank of humilith series can be determined and more evolutional information about coal composition and structure can be obtained by the infrared spectroscopic method.

关键词： aromatic_nucleus C--C bond infrared absorption wave number vitrinite humic coal.

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Fredholm operators in Toeplitz algebras associated with discrete abelian groups

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Chinese Science Bulletin 1998年第14期43卷 1175-1179页

作者： XU Qingxiang 1.and chen Xiaoman 2 1. Department of Mathematics, Shanghai Normal University, Shanghai 200234, China 2. Laboratory of Mathematics for Nonlinear Sciences and Institute of Mathematics, Fudan University, Shanghai 200433, China Department of Mathematics Shanghai Normal University Shanghai China Laboratory of Mathematics for Nonlinear Sciences and Institute of Mathematics Fudan University Shanghai China

The locally finite below sets are introduced and the Fredholm operators in Toeplitz algebras associated with discrete abelian groups are studied.

关键词： discrete abelian group quasi_ordered group Toeplitz operator Fredholm operator.

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Discovery of Permian island-arc basalts in the Cenxi area and the tectonic significance──A piece of evidence for the paleo-Tethyan tectonic belt in western Guangdong and eastern Guangxi

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Chinese Science Bulletin 1998年第21期43卷 1838-1842页

作者： ZHANG Boyou 1. ZHAO Zhenhua 1. SHI Manquan 1. YANG Shufeng 2 and chen Hanlin 2 1. Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 51.640, China 2. Department of Earth Sciences, Zhejiang University, Hangzhou 31.027, China Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou China Department of Earth Sciences Zhejiang University Hangzhou China

Cenxi Permian basalts are the late Palaeozoic island-arc type basalts first found in South China. REE and trace element characteristics and distribution patterns show that this volcanic formation, which has been isotopically dated at 261.MaB.P. by the 39Ar/ 40Ar method, is of an active continental marginal island arc type, and that the tectonic environment at that time was an island-arc marginal sea or minor ocean basin related with the paleo-Tethyan tectonic belt in western Guangdong-eastern Guangxi.

关键词： spilite-keratophyre pillow lava Permian continental margin paleo-Tethyan evolution.

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Research on Giant Magnetostrictive Actuator for Turning Vibration Control

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厦门大学学报（自然科学版） 2002年第S1期41卷 78-79页

作者： LI Guo-ping 1.2, WEI Yan-ding 1. ZHENG Di 2, chen Zi-chen 1.(1. Institute of Advanced Manufacture Engineering, Zhejiang University, Hangzhou 31.027, China 2. Dept. of Mechanical Engineering, Ningbo University, Ningbo 31.21., China)

Magnetostriction is a phenomenon in which a magneti c field is used to produce a change in size of some materials. This property has b een known in elements such as nickel, iron and cobalt. Because the rare-ear th alloy Terfenol-D can offer much larger strains than nickel, iron, cobalt, an d other smart materials such as piezoelectric materials, it is called giant magn etostrictive material. Making use of the giant magnetostrictive material, the gi ant magnetostrictive actuator has higher bandwidth and rapider response than oth er actuators. So it is widely used in active vibration control, especially in lo w frequency stage. In this paper, a turning vibration control system is develope d. The system has an actuator clamped in a flexor that is rigid in the feed and main cutting force directions, yet is flexible in the radial direction. The stru cture of the giant magnetostrictive actuator is developed after magnetic circuit and some structure parameter are calculated. According to the turning frequency , the transient and stable-state output of the giant magnetostrictive actuator is measured. The test result demonstrated that the actuator responses the input rapidly, and the actuator has perfect stable-state and transient output charact eristic. The characteristic includes the stable-state output linearity, repeata bility and transient delay between output displacement and input current.

关键词： turning vibration control giant magnetostrictive actuator magnetic circuit

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Effects of Electron Beam Local Postweld Heat Treatment on Microstructure and Properties of 30CrMnSiNi2A Steel Welded Joints

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厦门大学学报（自然科学版） 2002年第S1期41卷 47-48页

作者： chen Fu-rong 1. HUO Li-xing 1. ZHANG Yu-feng 1. ZHANG Li 1. LIU Fang-jun 2, chen Gang 2 (1. College of Materials Science and Engineering, Tianjin University, Tianjin 300072, China 2. Aviation Techniques Institute of Beijing, Beijing 1.0024, China)

To improve the microstructure and properties of the electron beam welded joints, the vacuum or furnace whole post weld heat treatment (FWPWHT) usually should be done on it. The electron beam local post weld heat treatment (EBLPWHT) is a rather new heat treatment procedure that provides the advantages of high precision, flexibility and efficiency, energy saving and higher productivity. In this paper, the microstructure, mechanical properties, fracture toughness and fatigue properties of electron beam welded joints of 30CrMnSiNi2A steel in as-welded (AW) and EBLPWHT conditions have been investigated respectively. The results show that the microstructures of different zones of joints in as-welded condition are changed by EBLPWHT procedure, in which the welds from coarse needle martensite into lath-shaped martensite; the main structures of heat affected zones (HAZ) from lath-shaped martensite into lower bainite. The properties of welded joints can be improved by the EBLPWHT in some extent, especially the fracture toughness of the welds and the fatigue crack resistance of welded joints can be sufficiently improved. However, more appropriate heat treatment parameters of the EBLPWHT have to be studied in order to increase the mechanical properties of base metal near by the HAZ.

关键词： electron beam welding electron beam local heat treatment microstructure fracture toughness fatigue properties

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Fringe View: Problems and Construction of Human Settlement Environment for "Village-in-City"

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Chinese Journal of Population,Resources and Environment 2005年第1期3卷 18-26页

作者： Mo Chuangrong , Li Xia , Wang Shugong 1.1.2 & chen Xingeng 1.1. Institute of Environmental Sciences, Sun Yat-Sen University, Guangzhou Guangdong 51.275, China 2. Center of Earth Environment & Resources, Sun Yat-Sen University, Guangzhou Guangdong 51.275, China Institute of Environmental Sciences Sun Yat-Sen University Guangzhou Guangdong 510275 China Center of Earth Environment & Resources Sun Yat-Sen University Guangzhou Guangdong 510275 China

The construction of human settlement environment is one of the important contents in the domain of sustainable development. We try to annotate human settlement environment for "village- in-city" from the angle of fringe view. According to the macro-system thought of human settlement environment science, the evolvement, which can be generalized into four phases, connotation and problems (including social, economic, and environmental problems) of "village-in-city" are discussed primarily in this paper. Some domestic and international researches and practices are also summarized and assessed in the paper. Based on the analysis, some appropriate clues and suggestions for the construction of "village-in-city" have been put forward.

关键词： human settlement environment urbanization "village-in-city" fringe view sustainable development

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Application of Fluorescence Pressure Transducer Technology to Pressure Measurement Test in High Speed Wind Tunnel

Application of Fluorescence Pressure Transducer Technology t...

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第24届中国控制与决策会议

作者： chen XueYuan 1.1. AVIC Aerodynamics Research Institute, Shenyang, 1.0034, China

Pressure measurement has always been an important part of aircraft wind tunnel tests. The traditional method of pressure measurement uses the model with a series of special pressure taps on its surface to get discontinuous pressure data. Recently, Pressure Sensitive Paint （PSP） technology which uses optical method for measuring pressure distribution of the surface of the specific area has attracted much attention as an effective approach for pressure measurement. This paper introduces the basic theory of the Pressure Sensitive Paint （PSP） measurement technology and the development of control system for the experiments. The analysis of the experiments data provides the credible evidence for the farther popularization of the Pressure Sensitive Paint （PSP） measurement technology.

关键词： Optical Pressure Measurement Pressure Sensitive Paint Experiments Control Digital CCD Camera

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Estimation on dynamic release of phosphorus from wind-induced suspended particulate matter in Lake Taihu

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Science China Earth Sciences 2004年第8期47卷 710-719页

作者： FAN chengxin1. ZHANG Lu1.2, QIN Boqiang1. WANG Sumin1. HU Weiping1.& ZHANG chen1.1. Taihu Lake Laboratory for Ecosystem Research, Nanjing Institute of Geography & Limnology, Chinese Academy of Sciences, Nanjing 21.008, China 2. Graduate School of Chinese Academy of Sciences, Beijing 1.0039, China Taihu Lake Lab. for Ecosystem Res. Nanjing Inst. of Geography/Limnology Chinese Academy of Sciences Nanjing 210008 China Grad. Sch. of Chinese Acad. of Sci. Beijing 100039 China

Through man-made disturbance experiments, the corresponding relationships be-tween suspended particulate matter (SPM) and wind speed in different lake areas were simu-lated, the physicochemical formal transformation and biological mineralizing and decaying processes of phosphorus in SPM were studied, the contribution of phosphorus transformation to phosphorus loading of the water of Lake Taihu was quantitatively estimated. The results show that about 0.44 t·a-1.loading in Lake Taihu mainly comes from phosphorus-releasing action of SPM in physicochemical transformed to soluble reactive phosphorus (SRP), and the contribution mainly from biological mineralizing and decaying was about 425.8 t·a-1. which is equal to 1..0% of the total external loading of Lake Taihu, namely 4.7—7.5 times as much as SRP loading en-tering the lake by the rivers; thus it is the important source in dynamical internal loading of the lake. The determining factors for dynamical internal loading in lakes are organic phosphorus content in suspended solid and its biological transition availability.

关键词： phosphorus release,wind wave disturbance,particulate decaying,dynamical loading,Lake Taihu.

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