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Role of Ordering energy in Formation of Grain Structure and Special Boundaries Spectrum in Ordered Alloys with L12 Superstructure

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Journal of Materials Science & Technology 2000年第6期16卷 585-590页

作者： O.B.Perevalova (inst.tute of Strength phys.cs and Material Science, Russian Academy of Sciences, Siberian Branch pr. Academicheskii, 2/1, 634048, Tomsk, Russia) E. V.Konovalova, N.A.Koneva and E. VKozlov (State University of Architecture and Building, Sol inst. of Strength phys. Tomsk 634048 Russian Federation

It was revealed that an average energy of special boundaries is proportional to APB energy in the alloys with the L12 superstructure. This fact proves the appearance of the GAPBs in the planes of location of special boundaries in coincidence sites of ordered alloys. It was determined that the more energy of special boundaries in ordered alloys, the more energy of complex stacking fault. There is a correlation between the distribution of special boundaries as a function its relative energy and ordering energy: the more ordering energy, the more degree of washed away of distribution. The correlation between average relative energy of special boundaries and ordering energy was detected: the more ordering energy, the more average energy of special boundaries. The reverse dependence between ordering energy and average number of special boundaries in grains limited by boundaries of general type was discovered.

关键词： Role of Ordering energy in Formation of Grain Structure and Special Boundaries Spectrum in Ordered Alloys with L12 Superstructure

RESONANT PHOTOEMISSION OF BULK CeO_(2) AND NANO-CeO_(2) FILMS

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Acta Metallurgica Sinica(English Letters) 2001年第6期14卷 539-543页

作者： M.I. Abbas, K. Ibrahim, Z.Y. Wu, J. Zhang, F.Q. Liu and H.J. Qian (Beijing Synchrotron Radiation Laboratory, inst.tute of high energy phys.cs, The Chinese Academy of Sciences, P.O. Box 918, Beijing 100039, China) Beijing Synchrotron Radiat. Lab. Inst. of High Energy Phys. Chinese Acad. of Sci. Beijing 100039 P.O. Box 918 China

Photoemission behaviors of nano-CeO2 films with particle sizes ranging from 8 nm to 50 nm and bulk CeO2 in Ce 4 d-4 f absorption region have been investigated. Resonant enhancements of Ce 4 f valance band and Ce 5 p bands for nano film and bulk material have been observed. The variation of electron density of states in valance bands of nano and bulk structures of CeO2 is discussed in terms of Ce 4 d-4 f resonance.

关键词： Nanostructured materials Optical films Oxides Photoemission Resonance

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B_c Meson Studies

高能物理与核物理 2002年第z1期26卷 1-10页

作者： CHANG Chao-Hsi (inst.tute of Theoretical phys.cs, Chinese Academy of Sciences, Beijing 100080, China) inst. of Theor. phys. Chinese Acad. of Sci. Beijing 100080 China

Our studies on the meson Bc arc briefly *** decays of the meson Bc to a P-wave charmonium Xc or hc are reported comparatively precisely because they are fresh

关键词：高能物理核物理增刊张肇西 B_c Meson Studies Rev

Electronic Structure of New Superconducting Perovskite MgCNi3

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Journal of Materials Science & Technology 2004年第2期20卷 203-205页

作者： Li CHEN, Hua LI and Liangmo MEIphys.cs and Microelectronic School, Shandong University, Jinan 250100, China Department of phys.cs, Linyi Teachers University, Shandong 276005, China phys. and Microelectron. Sch. Shandong Univ. Ji'nan 250100 China Dept. of phys. Linyi Teachers Univ. Linyi 276005 China

The electronic structures of new superconducting perovskite MgCNi3 and related compounds MgCNi2T (T=Co, Fe, and Cu) have been studied using MS-Xa method. In MgCNi3, the main peak of density of states is located below the Fermi level and dominated by Ni d. From the results of total energy calculations, it was found that the number of Ni valence electron decreases faster for the Fe-doped case than that for the Co-doped case. The valence state of Ni changes from +1.43 in MgCNi2Co to +3.02 in MgCNi2Fe. It was confirmed that Co and Fe dopants in MgCNi3 behave as a source of d-band holes and the suppression of superconductivity occurs faster for the Fe-doped case than that for the Co-doped case. In order to explain the fact that Co and Fe dopants in MgCNi3 behave as a source of d-band holes rather than magnetic scattering centers that quench superconductivity, we have also investigated the effects of electron (Cu) doping on the superconductivity and found that both electron (Cu) doping and hole (Co, Fe) doping quench superconductivity exist. Comparing with the hole (Co) doping, there was no much difference between Cu and Co doping. This suggests that Co and Fe doping do not act as magnetic impurity.

关键词： Electronic structure Superconductivity Density of states

The rms-flux relation of Cyg X-2 in the horizontal branch

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Science China(phys.cs,Mechanics & Astronomy) 2010年第S1期53卷 86-90页

作者： LI ZhiBing,LEI YaJuan,QU JinLu,ZHANG Shu & SONG LiMing Key Laboratory for Particle Astrophys.cs,inst.tute of high energy phys.cs,Chinese Academy of Sciences(CAS),Beijing 100049,China Chinese Acad Sci Inst High Energy Phys Key Lab Particle Astrophys Beijing 100049 Peoples R China

We have investigated the relation between the root mean square(rms) variability and the X-ray flux(rms-flux relation) of the Z source Cyg X-2,and as well the energy dependence based on the Rossi X-ray Timing Explorer(RXTE) *** currently focus on the horizontal branch(HB),due to the negative correlation in flux of the soft and the hard *** rms-flux correlation has energy dependence as follows:positive at hard X-rays(above 10 keV) but negative at soft X-rays(below 10 keV).This provides a feature different from the previous one,and may be suggestive of different origins of X-rays below and above 10 ***,the overall spectrum can be well fitted with a model consisting of a blackbody and Comptonization components,but the fitting results do not reveal any features around 10 keV that could account for such a change in the rms-flux relation.

关键词： accretion accretion disk—binaries:close-stars:individual(Cygnus X-2)-X-rays:binaries

THE APPLICATION OF HOMOGENEOUS FUNCTION ANALYSIS TO RELATIVISTIC WkB APPROXIMATIONS

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Acta Mathematica Scientia 1992年第1期12卷 71-78页

作者：卢书城倪光炯 Dept. of phys. Jiujiang Teacher's College Jiujiang 332000 China Dept. of phys. Fudan Univ. Shanghai 200433 China

This paper illustrates how homogeneous function analysis can be generalized. to relativistic quantum mechanics for finding the WKB energy levels of Dirac particle in the positive power-law potentials (V = lambda-r(v), S = lambda'r(v), lambda, lambda', v > 0). The results show that the equation determining energy levels contains a product of hypergeometric function with some gamma functions, and the energy of particle is proportional to (2n(r) + l + 3/2) 2v/1 + v under the condition that the relativistic effect plays a principal role in contrast with the (2n(r) + l + 3/2) 2v/2 + v dependence in nonrelativistic case.

关键词： relativistic Dirac determining gamma finding proportional definitely paradox devoted fairly

Scanning　Analysis　of　REE　in　Bastnaesite　with　Synchrotron　Radiation　X－Ray　Fluorescence　Microprobe

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Journal of Rare Earths 1996年第4期14卷 308-311页

作者：安庆骧王锐兵邓赛文潘巨祥吴应荣吴澄宇 NATL RES CTR GEOANAL BEIJING 100037PEOPLES R CHINA inst.high energy phys BEIJING 100039PEOPLES R CHINA CHINESE ACAD GEOL SCI INST MINERAL DEPOSITSBEIJING 100037PEOPLES R CHINA

The content of REE(***) in bastnaesite was measured by synchrotron radiation X-ray fluorescence *** analysis makes use of excitation of the REE K lines between 33 and 50 *** white beam from a Wiggler source at the Beijing Electron Positron Collider(BEPC) of the National Laboratory,in order to excite the *** bastnaesite from the same mineral area was powdered to particle size≤300 *** was then divided into two *** portion was used to be determined by XRF after depositing with oxalate and transforming into *** other was pressed into disk without any binder as the reference *** weight and the diamieter of the disk were 15 g and 26 mm respectively.

关键词： Synchrotron radiation X-ray fluomcence Rare earth analysis Bastnaesite

Manufacture of Raney Ni catalyst with metastable Ni_2Al_3 by high energy milling

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中国有色金属学会会刊：英文版 1999年第3期9卷 562-565页

作者： Teng Ronghou(滕荣厚) 1, Sun Shijie(孙世杰) 1, Liu Silin(刘思林) 1, Liu Xuequan(柳学全) 1, Ma Ruzhang(马如璋) 2,Liu Tao(刘涛) 3 1. Functional Materials inst.tute, Central Iron & Steel Research inst.tute, Beijing 100081, P.R.China 2. Depar Cent Iron & Steel Res inst Funct Mat Inst Beijing 100081 Peoples R China Univ Sci & Technol Beijing Dept Mat Phys Beijing 100083 Peoples R China Chinese Acad Sci Inst High Energy Phys Beijing Synchrotron Radiat Facil Beijing 100039 Peoples R China

The Ni Al alloy containing Cr, Fe additives were prepared as Raney Ni catalyst by high energy milling. The size and surface state of Ni Al alloy powder were studied by particle size analyzer and sanning electron microscopy, the structure was analyzed by XRD and Mssbauer methods. The results showed that after a high energy milling (HEM), the Ni Al alloy transforms to a nano scale NiAl structure with rich Al. By annealing the alloy, a metastable Ni 2Al 3 phase can be obtained.

关键词： Raney nickel catalyst nano crystal high energy milling

Influence of crystal materials on the synchrotron X-ray fluorescence analysis:a study of crystal and amorphous clinopyroxene

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Chinese Science Bulletin 1999年第12期44卷 1144-1146页

作者： Haifei Zheng Yuying Huang Peixue Ma Xing Ju Peking Univ Dept Geol Beijing 100871 Peoples R China Chinese Acad Sci Inst High Energy Phys Beijing 100039 Peoples R China

Synchrotron X-ray fluorescence analyses of crystal and amorphous clinopyroxene were compared. The results showed that using the synchrotron X-ray as a source of energy, the diffraction X-ray of crystal materials will seriously affect the X-ray fluorescence analysis. In order to avoid the influence of diffraction, the best way to solve it is to use the monochromatic source, or to have a collimating slit between sample and Si(Li) detector.

关键词： synchrotron radiation X-ray fluorescence analysis diffraction.