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行星重力的后牛顿近似对卫星作用的估计

物理学报 2001年第12期50卷 2497-2500页

作者：钟鸣乾西北大学物理系西安710069

将行星重力的广义相对论后牛顿近似应用于木星系统和撞击木星的彗星Shoemaker Levy 9,计算了木星重力的后牛顿改正和它的卫星的进动效应 ,并与地球月球系统作比较。

关键词：重力后牛顿近似木星卫星彗星 Shoemaker-Levy9 广义相对论行星估计太阳系进动效应地球-月球系统

ELECTRODEPOSITED NiSCo ALLOY USED AS HYDROGEN EVOLUTION REACTION CATHODE IN WATER ELECTROLYSIS

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Acta Metallurgica Sinica(English Letters) 2002年第4期15卷 405-408页

作者： Q.Han,J.S.Chen,K.R.Liu and X.J.WeiSchool of Materials & Metallurgy, Northeastern University, Shenyang 110004, China manuscript received 172001 in revised form 2 December 2001 School of Materials & Metallurgy Northea.stern University

NiSCo catalytic cathodes were obtained by electrodeposition in a typical Watt cell with addition of NH2CSNH2 and CoCl2. Using CoCl2 concentration, current density, temperature and pH value as main factors, an orthogonal experiment was designed to determine the optimum technological conditions according to HER overpotentials. The optimum technological conditions were obtained from the minimum HER overpoten-tial-70mV. The corresponding electrochemical parameters (Tafel slope b, exchange current density io) were determined by steady-state polarization curves. The content of S, Co and its microstructure were measured by EPMA and XRD.

关键词： NiSCo alloy electrodeposition HER

Water-Air Mixing Jet Produced by Electro-hydraulic Impulse Technology Strengthening the Quality of Surface of Metal Materials

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Journal of Materials Science & Technology 2002年第3期18卷 194-196页

作者： Zhenfang LIAO and Shijin ZHANGCollege of Mechanical Engineering, Chongqing University, Chongqing 400044, China [ manuscript received September 10, 2001, in revised form October 26, 2001] Chongqing Univ Coll Mech Engn Chongqing 400044 Peoples R China

Electro-hydraulic impulse water-air mixing jet by which the quality of metal materials can be improved is described in this paper. The experimental results proved that the hardness and the micro-hardness of the surface layer of metal materials can be improved with this method, for example, the microhardness of CrWMn can be increased by 35.62 percent.

关键词： Electro-hydraulic impulse Water-air mixing jet Quality of surface

INFLUENCE OF COLD ROLLING TECHNOLOGY ON TEXTURE EVOLUTION OF IF STEEL

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Acta Metallurgica Sinica(English Letters) 2002年第3期15卷 312-316页

作者： J.X. Li, X.H. Liu and G.D. WangState Key Laboratory of Rolling & Automation, Northeastern University, Shenyang 110006, China manuscript received 16 July 2001 in revised form 6 September 2001 *** State Key Laboratory of Rolling & Automation Northeastern University Shenyang 110006 China

Two kinds of cold rolling experiments, single cold rolling and double cold rolling, were carried out on one titanium stabilized interstitial free (IF) steel that has been warm rolled at ferrite temperature. The main aim was to investigate the evolution of rolling and annealing textures from the well known behavior observed under single cold rolling condition to the less understood double cold rolling by using orientation distribution function (ODF). In the twice cold rolled samples, the annealing texture comprises only single {111}(110-112) r-fibre texture when it subjected to moderate reduction in the first round of rolling. Accordingly both the once cold rolled sample and the twice cold rolled sample with heavy reduction in the first round of rolling have much complex texture components. They are related to the formation of initial {111} subgrain and the priority growth of stable {111} nucleus.

关键词： double rolling cold rolling reduction deformation texture annealing texture r-value

Numerical Simulation of the TIG Welding Arc Behavior

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Journal of Materials Science & Technology 2002年第1期18卷 43-46页

作者： Chuansong WU and Jinqiang GAOInstitute of Materials Joining, Shandong University, Jinan 250061, China [ manuscript received January 2, 2001, in revised form feb.uary 14, 2001] Inst. of Mat. Joining Shandong Univ. Jinan 250061 China

Achieving an effective utilization and exploitation of TIG welding arcs require a thorough understanding of the plasma properties and its physical processes. Through simultaneous solutions of the set of conservation equations for mass, momentum, energy and current, a mathematical model has been developed to predict the velocity, temperature, and current density distributions in argon welding arcs. The predicted temperature fields in arc regions, and the distribution of current density and heat flux at the anode agree well with measurements reported in literatures. This work could lay the foundation for developing a comprehensive model of the TIG welding process where a dynamic, two-way coupling between the welding arc and the weld pool surface is properly represented.

关键词： Welding Argon arc Plasma Behavior

Scattering Matrix Modeling of Photon Migration in Turbid Media

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Chinese Journal of Lasers 1999年第4期8卷 40-46页

作者： REN Hongwu FANG Zujie (Shanghai Institute of Optics and Fine Mechanics, The Chinese Academy of Sciences, Shanghai 201800, China) received Aug. 7, 1998 revised manuscript received March, 23, 1999 中科院上海光学精密机械所上海 201800 中科院上海光学精密机械所上海

A lattice random walk model based on walkers wandering on discrete lattice of scattering space by discrete spatial and temporal step is presented. The scattering matrix and linking matrix of the lattice random walk are given for the scattering and absorption processes in homogenous and inhomogeneous turbid media. All the results obey the principle of causality.

关键词： biomedical optics photon migration lattice random walk model

Laser Surface Hardening of 9CrSi Steel

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Journal of Materials Science & Technology 2002年第1期18卷 17-20页

作者： Nunghee RYU and Sunggoon KANGDivision of Materials Science and Engineering, College of Engineering, Hanyang University, Korea [ manuscript received August 7, 2001, in revised form September 20, 2001] Div. of Mat. Sci. and Eng. Coll. of Eng. Hanyang Univ. Hanyang South Korea

The effects of laser hardening parameters such as beam power, beam diameter and scanning rate on microstructure and hardness of 9CrSi steel were investigated. The microstructure of the surface layer of 9CrSi steel was changed from pearlite to martensite, retained austenite and carbide by laser hardening. The depth of the hardened layer increased with increasing laser energy density and the surface hardeness increased by 3-5 times as high as the untreated steel. The laser hardened surface had good wear resistance due to martensite and carbide in the surface layer. The wear mode at low speed was abrasive, while the wear mode at high speed was adhesive.

关键词： Laser hardening Martensite Hardeness Phase trasformation

Determination of Optical Properties of Turbid Media from Spatially Resolved Diffuse Reflectance by Neural Network

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Chinese Journal of Lasers 2000年第5期9卷 86-91页

作者： REN Hongwu FANG Zujie (Shanghai Institute of Optics and Fine Mechanics, The Chinese Academy of Sciences, Shanghai 201800, China) received June 10, 1999 revised manuscript received Jan. 7, 2000 中科院上海光学精密机械所上海

A backpropagation (BP) network is applied to the inversion of spatially resolved diffuse reflectance from turbid media and then to determine its optical properties. A standard BP network may be trapped to the local minimum. A BP network with variable momentum and variable leaning rate can reduce this effect. After being trained, this network will produce reduced scattering coefficients and absorption coefficients when the spatially resolved diffuse reflectance are fed to its input.

关键词： neural network backpropagation (BP) network spatially resolved diffuse reflectance turbid media

Effect of Stearic Acid on Ettringite Formation

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Journal of Materials Science & Technology 2002年第3期18卷 263-265页

作者： Essam A.KisharDepartment of Chemistry, Faculty of Girls, Ain Shams University, Cairo, Egypt [ manuscript received March 29, 2001, in revised form June 11, 2001] Ain Shams Univ Fac Girls Dept Chem Cairo Egypt

The hydration reaction of a mixture of tricalcium aluminate (C3A) and gypsum with the molar ratio of 1:3 was carried out at room temperature and a water/solid ratio of 4.0. The hydration was carried out in presence of 0, 1 and 3% stearic acid and the mixes were designated as A, B and C, respectively. Ettringite was the only hydration product formed in the presence and absence of stearic acid. Phase composition, microstructure, infra-red analysis as well as degree of hydration were carried out for the different hydration mixtures. The rate of ettringite formation in the presence of 3% stearic acid was accelerated during the first half hour of hydration, and then retardation was occurred. In the presence of 1% stearic acid the ettringite formation was accelerated first till 3 days, then retardation was observed at later hydration ages.

关键词： Stearic acid Hydration Ettringite