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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 3.002., 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 2.for Ml could improve its discharge capacity, but 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 2.for Ml could improve its discharge capacity, but 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

Proton induced X-ray emission (PIXE) analysis of sources of porcelain body of Ru Guan and Jun Guan porcelains

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Science china(physics,Mechanics & Astronomy) 2006年第4期49卷 411-420页

作者： LI Guoxia1, ZHAO Weijuan1, LI Rongwu2. SUN Hongwei1, GUO Min1, WANG Yanfang1, LIU Hui1, ZHAO Qingyun3. SUN Xinmin3. ZHAO Wenjun3.& CHENG Huansheng4 1. Faculty of Physical engineering, Zhengzhou University, Zhengzhou 450052. {3. 2. {2. of physics, Beijing Normal University, Beijing 100875, {3. 3. Institute of Cultural Relic and Archaeology of Henan Province, Zhengzhou 450000, {3. 4. Institute of Modern physics, Fudan University, Shanghai 2.043., {3. Faculty of Physical engineering Zhengzhou University Zhengzhou China department of physics Beijing Normal University Beijing China Institute of Cultural Relic and Archaeology of Henan Province Zhengzhou China Institute of Modern physics Fudan University Shanghai China

3. samples of Ru Guan porcelain body and 50 samples of Jun Guan porcelain body (both kinds being in different body colors) were selected with the purpose of finding out the source of raw materials and their classification relationship so as to search for ways of non-destructive discrimination. Proton induced X-ray emission (PIXE) has been applied to these samples to determine their chemical elements. The data of seven major chemical elements collected from these samples were further studied through fuzzy cluster analysis. Results indicate that the origin of raw materials of Jun Guan porcelain body samples is comparatively more concentrated in certain places, while that of Ru Guan porcelain body samples is scattered about. The places of origin of raw materials of the majority of Ru Guan and Jun Guan porcelain body samples have something in common, but some differences still exist. It might be an important way for non-destructive discrimination among Ru Guan and Jun Guan porcelains by combining PIXE with fuzzy cluster analysis.

关键词： Ru Guan and Jun Guan porcelain, source of porcelain body, PIXE, fuzzy cluster analysis, non-destructive discrimination.

A complex variable meshless method for fracture problems

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Science china(physics,Mechanics & Astronomy) 2006年第1期49卷 46-59页

作者： CHENG Yumin1 & LI Jiuhong2.1. Shanghai Institute of Applied mathematics and Mechanics, Shanghai University, Shanghai 2.0072. china 2. {2. of Building engineering, Xi’an University of Technology, Xi’an 710048, china Shanghai Institute of Applied mathematics and Mechanics Shanghai University Shanghai China department of Building engineering Xi’an University of Technology Xi’an China

Based on the moving least-square (MLS) approximation, the complex variable moving least-square approximation (CVMLS) is discussed in this paper. The complex variable moving least-square approximation cannot form ill-conditioned equations, and has greater precision and computational efficiency. Using the analytical solution near the tip of a crack, the trial functions in the complex variable moving least-square approxi- mation are extended, and the corresponding approximation function is obtained. And from the minimum potential energy principle, a complex variable meshless method for fracture problems is presented, and the formulae of the complex variable meshless method are obtained. The complex variable meshless method in this paper has greater precision and computational efficiency than the conventional meshless method. Some examples are given.

关键词： moving least-square approximation, complex variable moving least-square approximation, meshless method, complex variable meshless method, fracture.

Boundary element-free method for elastodynamics

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Science china(physics,Mechanics & Astronomy) 2005年第6期48卷 641-657页

作者： CHENG Yumin1 & PENG Miaojuan2.1. Shanghai Institute of Applied mathematics and Mechanics, Shanghai University, Shanghai 2.0072. china 2. {2. of Civil engineering, Shanghai University, Shanghai 2.0072. china Shanghai Institute of Applied mathematics and Mechanics Shanghai University Shanghai China department of Civil engineering Shanghai University Shanghai China

The moving least-square approximation is discussed first. Sometimes the method can form an ill-conditioned equation system, and thus the solution cannot be obtained correctly. A Hilbert space is presented on which an orthogonal function system mixed a weight function is defined. Next the improved moving least-square approximation is discussed in detail. The improved method has higher computational efficiency and precision than the old method, and cannot form an ill-conditioned equation system. A boundary element-free method (BEFM) for elastodynamics problems is presented by combining the boundary integral equation method for elastodynamics and the improved moving least-square approximation. The boundary element-free method is a meshless method of boundary integral equation and is a direct numerical method compared with others, in which the basic unknowns are the real solutions of the nodal variables and the boundary conditions can be applied easily. The boundary element-free method has a higher computational efficiency and precision. In addition, the numerical procedure of the boundary element-free method for elastodynamics problems is presented in this paper. Finally, some numerical examples are given.

关键词： moving least-square approximation, improved moving least-square approximation, elastodynamics, boundary integral equation, meshless method, boundary element-free method, Fourier eigen transform.

Existence and Uniqueness of Stationary Solutions of Non-Newtonian Viscous Incompressible Fluids

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Communications in Nonlinear Science and Numerical Simulation 1999年第1期4卷 63-68页

作者： Boling GUO* and Guoguang LIN**,+ (Institute of Applied physics and Computational mathematics, Beijing 100088, {2.) Guoguang LIN (Graduate School of {2. Academy of engineering physics, Beijing 100088, {2.) + (department of mathematics, Yunnan Unive Inst. Appl. Phys. and Compl. Math. Beijing 100088 China Graduate School China Academy of Engineering Physics Beijing 100088 China department of mathematics Yunnan University Kunming 650091 China

The existence and uniqueness of stationary solution a bipolar incompressible viscous fluids is *** is also obtained that the every solution of the system converges to the stationary solution as time t → ∞.

关键词： non-Newtonian fluid stationary solution, asymptotic behavior bipolar fluid

Nonsingularity in second-order cone programming via the smoothing metric projector

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Science china mathematics 2010年第4期53卷 1025-1038页

作者： WANG Yun 1,& ZHANG LiWei 2.1 College of Information Sciences and engineering,shandong Agricultural University,Tai’an 2.1018,{2. 2.department of Applied mathematics,Dalian University of Technology,Dalian 11602.,{2. College of Information Sciences and engineering Shandong Agricultural University Tai’an China department of Applied mathematics Dalian University of Technology Dalian China

Based on the differential properties of the smoothing metric projector onto the second-order cone,we prove that,for a locally optimal solution to a nonlinear second-order cone programming problem,the nonsingularity of the Clarke's generalized Jacobian of the smoothing Karush-Kuhn-Tucker system,constructed by the smoothing metric projector,is equivalent to the strong second-order sufficient condition and constraint nondegeneracy,which is in turn equivalent to the strong regularity of the Karush-Kuhn-Tucker ***,this nonsingularity property guarantees the quadratic convergence of the corresponding smoothing Newton method for solving a Karush-Kuhn-Tucker ***,the analysis does not need the strict complementarity condition.

关键词： second-order cone programming problem smoothing metric projector B-subdifferential Clarke’s generalized Jacobian smoothing Newton method

New evidence for lack of CMB power on large scales

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Science china(physics,Mechanics & Astronomy) 2010年第3期53卷 567-570页

作者： LIU Hao1 & LI TiPei1,2.3.1 Key Laboratory of Particle Astrophysics, Institute of High Energy physics, Chinese Academy of Sciences, Beijing 100049, {2. 2.department of physics & Center for Astrophysics, Tsinghua University, Beijing 100084, {2. 3.department of engineering physics & Center for Astrophysics, Tsinghua University, Beijing 100084, {2. Key Laboratory of Particle Astrophysics Institute of High Energy Physics Chinese Academy of Sciences Beijing China department of physics & Center for Astrophysics Tsinghua University Beijing China department of engineering {2. & Center for Astro{2. Tsinghua University Beijing China

A digitalized temperature map is recovered from the first light sky survey image published by the Planck team, from which an angular power spectrum of the cosmic microwave background (CMB) is derived. The amplitudes of the low multipoles (low-l) measured from the preliminary Planck power spectrum are significantly lower than those reported by the WMAP team. Possible systematical effects are far from enough to explain the observed low-l differences.

关键词： cosmology cosmic microwave background data analysis

Exotic structure of the third excited state in^(2.)Na

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Chinese Science Bulletin 2005年第23期50卷 2677-2680页

作者： LI Xihan1,2.3. LIANG Yujie1,2.3. DENG Fuguo1,2.3. LIU Zuhua1,4 & ZHOU Hongyu1,2.3.1. Key Laboratory of Beam Technology and Material Modification of Minister of Education, Beijing Normal University, Beijing 100875, china 2. Institute of Low Energy Nuclear physics, and {2. of Material Science and engineering, Beijing Normal University, Beijing 100875, china 3. Beijing Radiation Center, Beijing 100875, china 4. china Institute of Atomic Energy, Beijing 102.13. china Key Laboratory of Beam Technology and Material Modification of Minister of Education Beijing Normal University Beijing 100875 China Institute of Low Energy Nuclear physics Department of Material Science and Engineering Beijing Normal University Beijing 100875 China Beijing Radiation Center Beijing 100875 China china Institute of Atomic Energy Beijing 102413 China

The probability of the last proton being out of the binding potential, P and the root-mean-square (rms) ra- dius (1/2. of the third excited state in 2.Na are calcu- lated by means of asymptotic normalization coefficie... 详细信息

The probability of the last proton being out of the binding potential, P and the root-mean-square (rms) ra- dius (2.1/2. of the third excited state in 2.Na are calcu- lated by means of asymptotic normalization coefficient (ANC) method with the experimental date existing. The results are P=54.73. and 2.1/2.5.2. fm respectively. The P value and the contribution of the asymptotic part to the 2.1/2.are compared with those of several other low energy states in 2.Na. It is found that the valence particle in the third excited state has an obvious larger P than those of other states. The density distribution of the valence proton in this state is also compared with the nucleons in the nuclear core 2.Ne, and a far extended tail can be seen clearly. These results show that the third ex- cited state in 2.Na is a proton halo state.

关键词：钠第三激发态外部结构有效半径密度分布渐近标准化系数

Archean relic body at lower crust in Sulu area:Evidence from magnetic data

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Chinese Science Bulletin 2003年第6期48卷 589-593页

作者： WU Qifan1,2. LU Fengxiang3. LIU Qingsheng3. ZHENG Jianping3. WANG Maoji2.& WU Wenli4 1. department of {3. {2., Tsinghua University, Beijing 100084, china 2. Aero Geophysical Survey & Remote Sensing Center, Beijing 100083. china 3. china University of Geosciences, Wuhan 43.074, china 4. Institute of Geophysical & Geochemical Exploration, Langfang 065000, china department of engineering {2. Tsinghua University Beijing China Aero Geophysical Survey & Remote Sensing Center Beijing China china University of Geosciences Wuhan China Institute of Geophysical & Geochemical Exploration Langfang China

After the new 1︰1000000 aero magnetic data were processed and the three-dimensional inversion work was carried out, a vast high magnetic body northwestward was discovered. The magnetic body is located at the depth of about 2. km on the west side of Tanlu fault and at about 2. km on the east side of Tanlu fault beneath the Sulu area. There is a difference of vertical distance of 3.5 km in depth between both sides. We think that the magnetic body is an Archean metamorphic plate and belongs to the North china block. The discovery of the magnetic body is significant for us to reconstruct the structure model of the Sulu orogenic belt, delineate the suture of collision between the North china block and the Yangtze block, and estimate the depth of slipping surface when the eastside of Tanlu fault moved northward.

关键词：苏鲁地区地壳下层太古代残余体地球物理调查区域性磁场三维反演苏鲁造山带郯鲁断裂带大别-苏鲁超高压变质带