材料期刊网

Investigation of Instability of Lattice of Bi_2Sr_2CaCu_2O_x

Han ZHANG and Qingrong FENG (Dept. of Physics , Peking University , Beijing 100871 , China)Y.Zhao(School of Materials Science and Engineering , University of New South Wales , Sydney 2052 , NSW , Australia)F.Ritter and W.Assmus (Physikalisches Institut , J.W.Goet

材料科学技术（英文）

Bi2Sr2CaCu2Ox superconductor was studied by differential scanning calorimetry (DSC) and thermogravimetry (TG) in different atmospheres. It is discovered that there is a thermal anomaly in the DSC curve, associated with a weight loss in the TG curve before the melting of the sample. Careful thermal analysis and high temperature X-ray diffraction reveal that the thermal anomaly and the weight loss show an instability of the crystalline Iattice. By annealing the sample in oxygen and argon, respectively and then by TC measurement and thermal analysis, the coincidence of transition temperature with the instability is found. The coincidence is further confirmed by Y-doped 2212 phase.

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THE LIQUIDUS OF THE TERNARY Ag-Cu-Si ALLOY SYSTEM

Z.G. Liu , X.M. Luo , G.S. Guo and C.X. He G.B. Li and Q. Y. Zhang(Institute of Precious Metals , Kunming 650221 , China)(Institute of Chemistry and Moleculars Engineering , Beliing University , Beijing 100871 , China)

金属学报(英文版)

The liquidus of the ternary Ag-Cd-Si alloy system in the Ag-Cu rich region was determined by DTA. The ternary Ag-Cd-Si system was divided into two ternary systems Ag-Cu-Cuo.76Si0.24 and Ag-Cu0.76Si0.24-Si by the section of Ag-Cu0.76 Si0.24.There is one ternary eutectic point for both the systems with the composition of 12. 5at. %Ag+71. 7at.%Cu+15.8at. %Si and 30at.% Ag+44.7at.%Cu+25.3at.%Sirespectivelg and the temperatures of the eutectic points are 740 and 705℃ respectively.

关键词: Ag-Cd-Si ternary sytem , null

Photoelectrochemical Study of Passive Films on Sensitized Stainless Steel

Tianbao DU and Shenhao CHEN (Chemistry Dept. , Shandong University , Jinan 250100 , China)Maizhi YANG and Li CHEN (Chemistry Dept. , Peking University , Beijing 100871 , China)

材料科学技术（英文）

Passive films formed on sensitized stainless steel in sulphuric acid solutions have been studied using photoefectrochemical techniques. The results of the photocurrent measurement indicate that the passive films on sensitized stainless steel are characterised with n-type or p-type semiconductor in different potential regions. The difference in the photoelectrochemical behaviour can be interpreted assuming that the passive film is an iron-chromium oxide solid solution associated with various hydration degrees of the Cr(Ⅲ) oxides at various potentials

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University of Science and Technology Beijing

JIA Shizhen University of Science and Technology Beijing , China.

材料科学技术（英文）

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Abstracts of papers from Journal of University of Science and Technology Beijing

稀有金属（英文版）

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Towards the ultimate storage ring: The lattice design for Beijing Advanced Photon Source

中国物理C doi:10.1088/1674-1137/37/5/057003

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CORRELATION BETWEEN STRESS COMPONENTS AND STRESS CORROSION CRACKS IN BRASS Lecturer,Department of Materials Physics,University of Science and Technology Beijing,Beijing 100083,China

QIAO Lijie LIU Rui XIAO Jimei University of Science and Technology Beijing , Beijing , China

金属学报(英文版)

The effects of stress components on nucleation sites and propagation directions of stress cor- rosion cracks in brass were investigated with specimens under mode Ⅱ and mode Ⅲ loadings. The results indicated that under mode Ⅱ loading,stress corrosion cracks nucleated on the site with maximum normal stress component and propagated along the plane perpendieular to the maximum normal stress,under mode Ⅲ loading,the stress corrosion crack was not evident on the 45°plane due to the general corrosion in aqueous solution with high NH_4OH concentra- tion,while stress corroded in aqueous solution with low NH_4OH concentration, numerous cracks with spacings of 10—150μm were found on the 45°plane with maximum normal stress and no stress corrosion cracks was observed on the plane with maximum shear stress.

关键词: stress corrosion cracking , null , null , null

The Second International Conference on HSLA Steels Beijing,China,October 1990 Organized by THE CHINESE SOCIETY OF METALS

金属学报(英文版)

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Upgrade of beamline 3W1B at Beijing Synchrotron Radiation Facility

中国物理C doi:10.1088/1674-1137/37/5/058001

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’99北京国际热处理展览会(CHT’99，Beijing)

兵器材料科学与工程

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