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compression behavior of Zr_(41)Ti_(14)Cu_(12.5)Ni_(10)Be_(22.5) bulk metallic glass up to 24 GPa

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Science china(Physics,Mechanics & Astronomy) 2005年第3期48卷 319-324页

作者： LI Gong 1, 2 , ZHAN Zaiji 2 , LIU jing 3 , YUN jinku 1 , SUN Liling 2 , LIU Riping 1 , ZHANG jun 2 & WANG Wenkui 1, 2 1. key Laboratory of Metastable Materials Science and technology, Yanshan University, Qinhuangdao 066004, china 2. Center for condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, beijing 100080, china 3. BSRF, Institute of High energy Physics, Chinese Academy of Sciences, beijing 100039, china key Laboratory of Metastable Materials Science and technology Yanshan University Qinhuangdao China Center for condensed Matter Physics Institute of Physics Chinese Academy of Sciences Beijing China BSRF Institute of High Energy Physics Chinese Academy of Sciences Beijing China

The compression of a Zr41Ti14Cu12.5Ni10Be22.5 bulk metallic glass (BMG) is investigated at room temperature up to 24 GPa using in-situ high pressure energy dispersive X-ray diffraction with a synchrotron radiation source. The pressure-induced structural relaxation is exhibited. It is found that below about 8 GPa, the existence of excess free volume contributes to the rapid structural relaxation, which gives rise to the rapid volumetric change, and the structural relaxation results in the structural stiffness under higher pressure.

关键词： bulk metallic glass, high pressure, structural relaxation, synchrotron radiation.

Laboratory Investigation of Zinc Recovery fromEAF Dust by Bath Smelting Reduction

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International journal of Minerals,Metallurgy and Materials 2000年第1期14卷 18-23页

作者： Weiqing Chen Tarek El Gammal Metallurgy School, University of Science & technology beijing, beijing 100083, china Institute for Ferrous Metallurgy, Aachen University of technology, Germany Metallurgy School University of Science and Technology Beijing Beijing 100083 China Institute for Ferrous Metallurgy Aachen University of Technology Germany

Bath smelting reduction for recovering zinc from EAF (Electric Arc Furnace) dust has been investigated in the laboratory. A degree of zinc volatilization of more than 99% was obtained from the process. Temperature has a clear influence on the reduction rate of ZnO in slag. The reduction rate of (ZnO) by [C] is the first order with respect to the content of ZnO in the slag. The apparent activation energy of the (ZnO) reduction reaction is 312 kj/mol at 1300-1500℃.

关键词： EAF dust ZnO smelting reduction reduction rate

Simulation study of real-time monitor for BEPC-Ⅱ luminosity

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Science china(Technological Sciences) 2010年第5期53卷 1215-1219页

作者： SHAN Qing1,2,WU jian2,XUE Zhen2,XU ZiZong2,HU Tao3,WANG YiFang3 & WANG XiaoLian2 1 college of Material Science and technology,Nanjing University of Aeronautics and Astronautics,Nanjing 210016,china 2 Department of Modern Physics,University of Science and technology of china,Hefei 230026,china 3 Institute of High energy Physics,Chinese Academy of Sciences,beijing 100049,china college of Material Science and technology Nanjing University of Aeronautics and Astronautics Nanjing China Department of Modern Physics University of Science and Technology of China Hefei China Institute of High energy Physics Chinese Academy of Sciences Beijing China

A fast and real time luminosity monitor system will be used in the BEPC-Ⅱ(beijing Electron Positron collider,china).Photons generated in radiative Bhabha scattering at the interaction point are transformed into charged particles,and then the luminosity of each bunch pair is measured through collecting the Cherenkov light produced by charged particles in fused *** whole process happening in the detector is *** physics acceptance and detection threshold with the monitor accu-racy of 1% are set based on the simulation spectra of photoelectron yield calibrated by e-beam data.

关键词： luminosity BEPC-Ⅱ Cherenkov detector radiative Bhabha

Nonequilibrium Thermodynamic and Dissipative Structure Mechanism of Fluidized Beds

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International journal of Minerals,Metallurgy and Materials 1999年第2期13卷 90-93页

作者： Maozhan Qi Li Wang Xuezi Ni (Mechanical Engineering School, University of Science and technology beijing, beijing 100083, china) Mechanical Engineering School University of Science and Technology Beijing Beijing 100083 China

Fluidized beds are nonlinear dynamic systems that exchange mass and energy with outside. They are governed not only byfluid dynamics, but by thermodynamics, especially the second law of thermodynamics as well. According to Prigogine's dissipative structure theory, the following have been concluded: (l) a fixed bed is on thermodynamic blanch, and bubbling, turbulent and fast beds areon the dissipatve structure branches. (2) Entropy in fluidized beds is divided into tWo parts: entropy production and entropy flux. The latter increases with gas velocity and decreases with pressure of the systems. That means the entropy of a system may reduce and the systemwith higher gas velocity behaves as dissipative structure characteristics. (3) For a giVen velocity, a fluidized bed operates stably on thewhole, but it is unstable to local gas-solid phases. The unstable phases are described by fluid dynamic equations, While the minimum ofsystem energy function assures whole stability of the system. (4) A transition criterion of a bubbling bed is derived from Prigogine's stability theory.

关键词： fluidized bed nonequilibrium thermodynamics dissipative structure energy extremum

FORMATION OF HEXAGONAL co_(2—3)C IN co BY CARBON ION IMPLANTATION

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Acta Metallurgica Sinica(English Letters) 1992年第2期5卷 137-140页

作者： WANG jian WU Xingfang CHEN Xunping CAI jun University of Science and technology beijing,beijing,china LIU Baixin Tsinghua University,beijing,china FANG Zhengzhi beijing Institute of Space Physics,Academia Sinica,beijing,china Univ of Science and technology Beijing Beijing China

co thin films were subjected to 50 keV carbon ion *** the dose of 2.5× 10^(17)/cm^2,a hexagonal co-carbide phase was observed for the first *** lattice con- stants from electron diffraction are a=0.2685 nm and c=0.4335 *** phase does not dis- appear until the dose of 9×10^(17)/cm^*** spectra showed that the stoichiometry was co_(2-3)*** behavior of the ferromagnetic carbides along the descending sequence of Ni-Fe-co by Fermi energy of solids was ***,based on the kinetic con- dition of phase transformation and the band theory of solids,a possible explanation about the difference of the results of ion-metallurgy and thermal metallurgy was proposed.

关键词： ion implantation phase Fermi energy co co_(2_3)C

Water-affinity of Perlite Products and Its Anti-water Mechanism after Being Modified

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International journal of Minerals,Metallurgy and Materials 1999年第3期13卷 196-198页

作者： Cunyi Song Wen Ni Deping Chen(Resources Engineering School, University of Science and technology beijing, beijing, 100083, china) Resources Engineering School University of Science and Technology Beijing Beijing 100083 China

The structure modification and its mechanism have been studied when perlite products changed from water-affinity state to anti-water state. The structure of fused perlite and its surface physicochemical properties have also been studied. The modification of perlite products has provided the products with anti-water property, which not only enhanced the quality of thermal insulating function, reduced the lost of heat energy, but also made the products water-proof These modified perlite products are used as ideal thermal insulating layers for the thermodynamic equipment and heat transporting conducts.

关键词： water-affinity anti-water property perlite surface sodification

Molecular mechanism of dehydrin in response to environmental stress in plant

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Progress in Natural Science:Materials International 2007年第3期17卷 237-246页

作者： ZHANG Yuxiu , WANG Zi and XU jin (Department of Bioengineering, School of Chemical and Environmental Engineering, china University of Mining and technology (beijing), beijing 100083, china Department of Biology, Graduate University of Chinese Academy of Sciences, beijing 100049, china) Department of Bioengineering School of Chemical and Environmental Engineering China University of Mining and Technology (Beijing) Beijing 100083 China Department of Biology Graduate University Chinese Academy of Sciences Beijing 100049 China

Dehydrins, known as the D-11 subgroup of late embryogenesis abundant (LEA) protein, are an immunologically distinct family of proteins, which typically accumulate in desiccation-tolerant seed embryo or in vegetative tissues in response to various environmental stresses such as drought, salinity and freezing. The existence of conservative sequences designated as k, S, and Y segments is a structural feature of dehydrins, and the k segment found in all dehydrins represents a highly conserved 15 amino acid motif (EkkGIMDkIkEkLPG) and forms an amphiphilicα-helix. According to the arrangement of these domains and clustering analysis, dehydrins are subdivided into 5 subtypes: YnSk, kn, knS, Skn and Ynk. Different types of dehydrins are induced by different environmental stress in plants. Study results showed that dehydrins might play important protective roles under abiotic stress via a number of different mechanisms, including improving or protecting enzyme activities by the cryoprotective activity in responding to freeze/thaw or dehydration; stabilizing vesicles or other endomembrane structures by function as the membrane stabilizer during freeze induced dehydration, and preventing the membrane system from the oxidative damage induced by reactive oxygen radicals as the radical scavenger. Here, the gene expression and molecular mechanisms of dehydrin in response to stress in plants are discussed.

关键词： dehydrin stress mechanism.

Formation of complexes of Rubisco-Rubisco activase from La^3+, Ce^3+ treatment spinach

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Science china Chemistry 2005年第1期48卷 67-74页

作者： HONG Fashui1, LIU Chao1, ZHENG Lei1, WANG Xuefeng1, WU kang1, SONG Weiping1, Lü Shipeng1, TAO Ye2 & ZHAO Guiwen3 1. college of Life Sciences, Suzhou Universty, Suzhou 215006, china 2. Synchrotron Radiation Laboratory, Institute of High energy Physics, The Chinese Academy of Science, beijing 100039, china 3. Chemical Department, University of Science and technology of china, Hefei 230026, china college of Life Sciences Suzhou Universty Suzhou China Synchrotron Radiation Laboratory Institute of High Energy Physics The Chinese Academy of Science Beijing China Chemical Department University of Science and Technology of China Hefei China

The complex of Rubisco and Rubisco activase from LaCl3-, CeCl3- treated spinach in vivo is induced. SDS-PAGE result shows that the purified proteins from LaCl3-, CeCl3- treated spinach have not only large and small subunits (55 kD, 14.4 kD) of Rubisco, but also two large subunits of 45 kD and 41 kD near the large subunits of Rubisco. Native-PAGE shows that the purified proteins from LaCl3-, CeCl3- treated spinach have not only a band of Rubisco (560 kD), but also a band of about 1100 kD, about twice distant from Rubisco, which might be a complex of Rubisco and Rubisco activase. The purified enzyme activities from LaCl3-, CeCl3-treated spinach are 1.8 and 2.8 times that of the control,the intensities of absorption and fluorescence are sig- nificantly higher than that of the purified Rubisco from the control, and the total sulfhydryl groups and available sulfhydryl groups are 36—39 –SH per mol enzyme, 14—25 –SH per mol enzyme more than those of the purified Rubisco from the control, respectively. The CD spectra show that the secondary structure of the purified enzyme from LaCl3-, CeCl3 -treated spinach is very dif- ferent from the control. The enzyme activities from LaCl3-, CeCl3- treated spinach in vivo are 1.5 and 1.9 times those of the control.

关键词： La3+, Ce3+, spinach, Rubisco, complex of Rubisco and Rubisco acitivase, spectral characteristics.

A coMPUTERIZED SYSTEM ON kINETIC ANALYSIS AND EVALUATION OF GAS/SOLID REACTIONS

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Acta Metallurgica Sinica(English Letters) 2003年第6期16卷 495-506页

作者： j.H. Liu, j. Y. Zhang and S.k. WeiSchool of Metallurgical and Ecological Engineering, University of Science & technology beijing, beijing 100083, china Sch. of Metall. and Ecological Eng. Univ. of Sci. and Technol. Beijing Beijing 100083 China

The present paper presents the structure, features and functions of a computerized system on kinetic analysis and evaluation of gas/solid reactions, kinPreGSR. kin-PreGSR is a menu driven system, can be operated with MS Windows as workbench in a PC computer. It has been developed using visual C++ with FoxPro hybrid coding technique.kinPreGSR combines the characteristics of gas/solid reactions with the kinetic models as well as mass and heat transfer equations. The database files were established for the apparent activation energies of some reduction and decomposition reactions to allow the prediction of the reaction kinetics to some extents. Outputs can be displayed using graphical or numerical forms. Examples regarding the oxide reduction and carbonate decomposition under isothermal conditions are given to show those functions.

关键词： gas/solid reaction kinetics computer system evaluation anal-ysis