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Chinese science Bulletin 1997年第21期42卷 1807-1810页

作者： XIE Hongsen, ZHANG Yueming, GUO Jie, XU Ji’an, SONG Maoshuang, XU Yousheng and HOU Wei1. institute of Geochemistry, Chinese Academy of sciences, Guiyang 550002, china 2, institute of earth science, academia sinica, taipei, china institute of Geochemistry Chinese Academy of Sciences Guiyang China institute of earth science Academia Sinica Taipei China

IT is very important to measure physical parameters of minerals, rocks, melts and fluids athigh pressure and high temperature. The data from these experiments can provide materialsfor explanation of geophysical observations on large scale, and information of geochemicalfield. Therefore, we set up measurement methods on elastic wave velocity, electrical conduc-tivity and differential thermal analysis in YJ-3000 ton press fitted with a wedge-type

关键词： physical parameters earth’s material high temperature and nltrahigh pressure.

Experimental studies on silicate structures of basaltic glasses quenched at 1 650℃ and 1—3.5 GPa

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Chinese science Bulletin 1999年第5期44卷 461-466页

作者： ZHUWeiguo, XIEHongsen, XU Jian, HOUWei, ZHANG Yueming, QUO Jie and XU Zhuming earth ’s Interior Material Laboratory, institute of Geochemistry, Chinese Academy of sciences, Guiyang 550002, china institute of earth science, academia sinica , Taibei, Taiwan, china earth’s Interior Material Laboratory Institute of Geochemistry Chinese Academy of Sciences Guiyang China institute of earth science Academia Snica Taibei Taiwan China

A series of melting experiments was carried out at 1 650℃ and 1.00-3.00 GPa using alkaline basalt as starting material. The compositions of quenched basaltic glasses in the products were detected by electron micro probe. Their CIPW norms were calculated and their refractive indices were determined by the oil-infused method. The Raman spectrum of the quenched basaltic glasses indicates that their main structural species are monomer [SiO4]4-, chain [Si2O6]4- and sheet [Si2O5]2- . The relationship at the same temperature between the proportions of integrated areas of structural species, and compositions and pressures was discussed.

关键词： quenched basaltic glass structure of melt Raman spectrum.

SUPERCONVERGENCES OF THE ADINI'S ELEMENT FORSECOND ORDER EQUATION

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Journal of Computational Mathematics 1999年第6期17卷 569-574页

作者： Ping Luo(Department of Computer science and Technology, Qinghua University, Beijing 100084,china)Qun Lin(institute of Systems science, academia sinica, Beijing, 100080, china) Tsing Hua Univ Dept Comp Sci & Technol Beijing 100084 Peoples R China Acad sinica Inst Syst Sci Beijing 100080 Peoples R China

n this papers the asymptotic error expansions of Adini's element for the secondorder imhomogeneous Neumann problem are given and the superconvergence estimations are obtained. Moreover, a numerical example to support ... 详细信息

关键词： Adini's element Superconvergence estimation Asymptotic expansion.

Existence of the Uniformly Minimum Risk Unbiased Estimator in Seemingly Unrelated Regression System

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Acta Mathematica sinica,English Series 1995年第1期11卷 23-28页

作者： Wu Qiguang institute of Systems science academia sinica Beijing,100080 china lay.psych.mun.ca

For a seemingly Unrelated regression system with the assumption of normality,a necessary and sufficient condition for the existence of the Uniformly Minimum Risk Unbiased (UMRU)estimator of regression coefficients under strictly convex loss is obtained;it is proved that any unbiased estimator can not improve the least squares estimator;it is also shown that no UMRU estimator exists under missing observations.

关键词： Existence of the Uniformly Minimum Risk Unbiased Estimator in Seemingly Unrelated Regression System

Rashba electron transport in one-dimensional quantum waveguides

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science china(Physics,Mechanics & Astronomy) 2010年第1期53卷 16-23页

作者： LIU DuanYang 1 , XIA JianBai 1,2 & CHANG YiaChung 2 1 State Key Laboratory for Superlattices and Microstructures, institute of Semiconductors, Beijing 100083, china 2 Research Center for Applied sciences, academia sinica, taipei, Taiwan 11529, china 1. State Key Laboratory for Superlattices and Microstructures Institute of Semiconductors Beijing 100083 China2. Research Center for Applied Sciences Academia Sinica Taipei Taiwan 11529 China

The properties of Rashba wave function in the planar one-dimensional waveguide are studied, and the following results are obtained. Due to the Rashba effect, the plane waves of electron with the energy E divide into two kinds of waves with the wave vectors k 1 =k 0 +k δ and k 2 =k 0 -k δ , where k δ is proportional to the Rashba coefficient, and their spin orientations are +π/2 (spin up) and -π/2 (spin down) with respect to the circuit, respectively. If there is gate or ferromagnetic contact in the circuit, the Rashba wave function becomes standing wave form exp(±ik δ l)sin[k 0 (l-L)], where L is the position coordinate of the gate or contact. Unlike the electron without considering the spin, the phase of the Rashba plane or standing wave function depends on the direction angle θ of the circuit. The travel velocity of the Rashba waves with the wave vector k 1 or k 2 are the same hk0/m * . The boundary conditions of the Rashba wave functions at the intersection of circuits are given from the continuity of wave functions and the conservation of current density. Using the boundary conditions of Rashba wave functions we study the transmission and reflection probabilities of Rashba electron moving in several structures, and find the interference effects of the two Rashba waves with different wave vectors caused by ferromagnetic contact or the gate. Lastly we derive the general theory of multiple branches structure. The theory can be used to design various spin polarized devices.

关键词： Rashba wave function one-dimensional waveguide boundary condition

INFLUENCE OF APPLIED POTENTIAL AND LOADING WAVEFORM ON FATIGUE CRACK GROWTH FOR STEEL A537 IN 3.5% NaCl SOLUTION

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Acta Metallurgica sinica(English Letters) 1993年第12期6卷 459-464页

作者： LI Jin WANG Zengfu KE Wei Corrosion science Laboratory,institute of Corrosion and Protection of Metals,academia sinica,Shenyang,china institute of Corrosion and Protection of Metals,academia sinica,Shenyang 110015,china Inst of Corrosion and Protection of Metals Shenyang China

Influence of applied potentials and loading waveform on the fatigue crack growth for steel A537 in 3.5% NaCl solution,and corresponding straining electrode behaviour have been *** the applied potentials over or below -800mV(SCE),the anodic dissolution or the hydrogen embrittlement is predominatant,*** applied anodic potential,the acceleration effect of continuous loading pattern on the CF crack growth mainly appeared at the range of low ΔK values,while for cathodic potential,it appeared at the high ΔK *** continuous straining causes a decrease of natural potential and an increase of anodic dissolution current.

关键词： corrosion fatigue steel A537 waveform potential straining eleclrode

NON-EQUILIBRIUM SEGREGATION STRUCTURE OF P IN COLD ROLLED Fe-P ALLOYS AND ITS RELATION WITH TEXTURE VARIATION

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Acta Metallurgica sinica(English Letters) 1992年第6期5卷 425-431页

作者： ZHANG Lixin NING Hua Laboratory of Corrosion science,institute of Corrosion and Protection of Metals,academia sinica.Shenyang,chinaZHOU Jing LI Liguang institute of Metal Research,academia sinica,Shenyang,china Professor,institute of Corrosion and Protection of Metals,academia sinica,Shenyang 110015,china Inst of Corrosion and Protection of Metals Acad Sinica Shenyang China

The relations between the non-equilibrium segregation process of P and the change of the texture in Fe-P alloys have been studied by analytical electron microscope and orientation distribution *** was shown that P segregated preferentialy on the{110}slip planes, the P segregation structures with repeating cycle a=1.582 nm form at 450℃.// ND direction abated.//ND direction ***{111}has a tendancy to transform into{111}texture in recovering process.{111}direction trans- forms into{111}2>direction after recrystalizing.A model to describe the effects of non-equilibrium segregation structures of P on orientation change was proposed and em- ployed to interpret the experiment results.

关键词： Fe-P Alloy lattice image recovering process non-equalibrium segregation structure

A UNIFORM GROWTH ESTIMATES OF SOLUTIONS OF ASYMPTOTICALLY ELLIPTIC OPERATORS

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Chinese Annals of Mathematics,Series B 2000年第2期21卷 259-268页

作者： ZHANG LIQUN(institute of Mathematics, academia sinica, Beijing 100080, china.) institute of Mathematics Academia Sinica Beijing 100080 China

This paper introduces a generic eigenvalue flow of a parameter family of operators, where the corresponding eigenfunction is continuous in parameters. Then the author applies the result to the study of polynomial growth L-harmonic functions. Under the assumption that the operator has some weakly conic structures at infinity which is not necessarily unique, a Harnack type uniform growth estimate is obtained.

关键词： Harmonic functions Polynomial growth Eigenvalue Laplacian operator

EFFECTS OF ACTIVE ELEMENTS Y AND Ce ON HIGH TEMPERATURE OXIDATION OF Fe-25Cr-40Ni ALLOY

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Acta Metallurgica sinica(English Letters) 1992年第11期5卷 383-390页

作者： YU Fanghua YANG Guohua Shanghai institute of Nuclear Research,academia sinica,Shanghai,chinaHAN Rongdian WENG Huimin University of science and Technology of china,Hefei,chinaSHEN Jianian Corrosion science Laboratory,institute of Corrosion and Protection of Metals academia sinica,Shenvang,china Shanghai Inst of Nuclear Research Acad Sinica Shanghai China

The effects of small amount(≥0.05%)of active elements Y and Ce in Fe-25Cr-40Ni al- loy have been investigated on the kinetics of early stage of high temperature oxidation as well as composition and microsructure of oxide film by ion backscattering and slow positron *** results show that Y and Ce can reduce evidently the high tem- perature oxidation rate of FeCrNi alloy at early stage and can effectively enhance the Cr_2O_3 formation and retard the oxide formation of Fe and Ni in the surface layer thus the microstructure of the oxide film is improved.Y and Ce enter the oxide film and concentrate within several tens nanometres from surface of the outer *** mech- anism of oxidation resistance for Ce is different from *** can decrease the density of vacancy defects in oxide layer,so the cations are restrained from diffusion outward through *** Y can control the outward diffusion of cations through va- cancies at the early statge of oxidation(shorter than 12 min),aften that restrained the cations from diffusion outward along grain boundaries up to 60 min oxidation.

关键词： ion backscattering slow positron beam oxidation active elements FeCrNi alloy

CHARACTERIZATION AND CONSTRUCTION OF LINEAR SYMPLECTIC RK-METHODS

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Journal of Computational Mathematics 1994年第2期12卷 101-112页

作者： Sun Geng (institute of Mathematics, academia sinica, Beijing, china) CHINESE ACAD SCI INST MATH BEIJING PEOPLES R CHINA

A characterization of linear symplectic Runge-Kutta methods, which is based on the W-transformation of Hairer and Wanner, is presented. Using this characterization three classes of high order linear symplectic Runge-Kutta methods are constructed. They include and extend known classes of high order linear symplectic Runge-Kutta methods.

关键词： RK CHARACTERIZATION AND CONSTRUCTION OF LINEAR SYMPLECTIC RK-METHODS high