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Progress in Natural Science:materials international 2005年第11期15卷 982-987页

作者： BAI Suxia, FU Yayuan, KONG Gang and WANG Yanling (State Key Laboratory of Reproductive Biology, Institute of Zoology, chinese academy of sciences, Beijing 100080, china The Second Hospital of chinese Medicine College, shenyang 110003, china) State Key Laboratory of Reproductive Biology Institute of Zoology Chinese Academy of Sciences Beijing 100080 China. The Second Hospital of chinese Medicine College Shenyang 110003 China

The invasion of cytotrophoblast cells into the maternal endometrium during embryonic implantation is very similar to the metastasis of carcinoma cells. However, the significant difference is that the former is a highly controlled process. In this report, the effects of integnn αvβ3 on the secretion of matrix metalloproteinase (MMP) were compared between normal cytotrophoblast cells and chorio-carcinoma cells by RT-PCR, gelatin zymography and immunocytochemistry. The results reveal that both normal cytotrophobiast cells and choriocarcinoma cells can express integrin αvβ3. The secretion of MMPs in normal cytotrophoblast cells is up-regulated by anti-αvβ3 antibody, whereas, decreased in choriocarcmoma cells. It was suggested that αvβ3 can modulate the expression of MMPs in trophoblasts, and this action is carried out through distinct mechanisms in normal and carcinoma cytotrophoblast cells.

关键词： cytotrophoblast cells choriocarcinoma cells integrfn αvβ3 matrix metalloproteinase.

Stabilization effects of third element on CaCu5 type derivatives of rare-earth transition-metal intermetallics

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Progress in Natural Science:materials international 2002年第2期 3-12页

作者： LIANG Jingkui, LIU Quanlin, HUANG Feng, RAO Guanghui and CHEN Xiaolong( Institute of physics and Center for Condensed Matter physics, chinese academy of sciences, Beijing 100080, china international Center of Material physics, chinese academy of sciences, shenyang 110015, china)

Part of the results of the key project "Search for novel rare-earth functional materials" supported by the National Natural Science Foundation of china is reviewed. In combination with reports in literature, the effects of the third element M on the formation and stability of La2(Co, M)17, R(Fe, M)12 and R3(Fe, M)29 intermetallic compounds are discussed by considering mixing enthalpy of M with rare-earth, Fe and Co, and atomic radius, electronegativity and electronic configurations, etc. It is concluded that the mixing enthalpy and atomic radius dominate the preferential sites and the minimum amount of M required to stabilize a structure, which ultimately affect the magnetic properties of a compound prominently. This review should provide some heuristic hints for exploiting novel rare-earth transition metal functional materials and for improving their performance.

关键词： La2(Co M)17 R(Fe M)12 Rs(Fe M)29 crystal structure magnetic properties.

Correlation of the Mechanical Properties of Polycrystalline Ni_3Al Alloys with Their Electronic Structure

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Journal of materials Science & Technology 1993年第3期9卷 226-228页

作者： Wen DENG Liangyue XIONG Chiwei LUNG international centre for materials physics,Institute of Metal Research,Academia Sinica,shenyang,110015,chinaShuhe WANG Jianting GUO Institute of Metal Research,Academia Sinica,shenyang,110015,china

The electronic structure of Ni_3Al alloys with different B contents has been investigated by measuring the positron lifetime *** segregation of B atoms to defects could form strong covalent bondings with Ni and Al atoms and make the electronic structure in those locations similar to that in bulk,thus strengthen their *** interaction of B atoms,which were solid-solutioned in the crystal lattice of Ni_3Al in a manner of occupying interstitial sites,with Ni and Al atoms resulted in the increase of the density of valent electrons,thus increased the bonding cohesion in *** im- provement of the mechanical properties of Ni_3Al alloys by B doping was due to both“grain bounda- ry effect”and“bulk effect”of B,which correlated with their electronic structure.

关键词： electronic structure B addition mechanical properties Ni_3Al alloy

Hydrogen storage properties of Laves phase Ti_(1-x)Zr_x(Mn_(0.5)Cr_(0.5))_2 alloys

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Rare Metals 2006年第z1期25卷 218-223页

作者： GUO Xiumei WU Erdong WANG Sucheng shenyang National Laboratory for materials Science Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China Shenyang National Laboratory for Materials Science Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China Shenyang National Laboratory for Materials Science Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China

The activation behaviors and hydrogen storage properties of the Laves phase Ti1-xZrx(Mn0.5Cr0.5)2 (x=0, 0.1, 0.2, 0.32, 0.5) alloys were investigated by the pressure-composition-temperature (P-C-T) measurements. All the studied alloys show the single C14-type Laves phase structure based on the XRD data. Except for the alloys with very low Zr content of x=0 and x=0.1, all these alloys can be fully activated. The P-C isotherms of the activated alloys show that, the introduction of Zr induces the decrease of the equilibrium pressures and the steeper plateaus. As the x increases, the maximum hydrogen absorption also increases, whereas the desorption of hydrogen decreases. These two effects result in a maximum reversible hydrogen storage capacity of H/M=3.03 for the alloy at x=0.32. Furthermore, the well-defined plateau associated with the smallest hysteresis also appears at x=0.32.

关键词： Laves phase hydrogen storage alloys activation behavior P-C isotherms

First-principles study of the effects of Si doping on geometric and electronic structure of closed carbon nanotube

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Science Bulletin 2005年第17期 9-14页

作者： ZHOU Junzhe1 & WANG Chongyu1, 2 1. Department of physics, Tsinghua University, Beijing 100084, china 2. international centre for materials physics, chinese academy of Sci-ences, shenyang 110016, china

The effects of Si doping on geometric and elec-tronic structure of closed carbon nanotube (CNT) are stud-ied by, a first-principles method, DMol. It is found that the local density of states at the Fermi level (EF) increases due to the Si-doping and the non-occupied states above the EF go down toward the lower energy range under an external elec-tronic field. In addition, due to the doping of Si, a sub-tip on the CNT cap is formed, which consisted of the Si atom and its neighbor C atoms. From these results it is concluded that Si-doping is beneficial to the CNT field emission properties.

关键词： carbon nanotube doping electronic structure field emission.

Interfacial Characteristics of Nanocrystalline FeMoSiB Alloys

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Journal of materials Science & Technology 1993年第4期9卷 268-272页

作者： Xuedong LIU Jingtang WANG State Key Lab.of RSA,Institute of Metal Research,Academia Sinica,shenyang,110015,chinaJie ZHU Jian JIANG international centre for materials physics,Institute of Metal Research,Academia Sinica,shenyang,110015,china

By using X-ray diffraction (XRD), transmission electronic microscopy (TEM) and transmission Mssbauer spectroseopy (TMES), the formation, structure and properties including microhardness and electrical resistivity of nanocrystalline FeMoSiB alloys have been investigated. By annealing the as-quenched FeMoSiB sample at 833-1023K for 1 h, nanocrystalline materials with grain sizes of 15 to 200 nm were obtained. Mssbauer spectroscopy results reveal a quasi-continuous distribution feature of P(H)-H curves for 15 nm-and 20 nm-grained samples. Also, it was found that resistivity and microhardness of nanocrystalline Fe-Mo-Si-B alloys exhibit strong grain size effect.

关键词： nanocrystalline alloy grain size effect intertace

Synthesis and characterization of nanocrystalline Ni produced by cryomilling in liquid nitrogen

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Rare Metals 2007年第2期26卷 147-151页

作者： YANG Bin FAN Jianzhong HAO Bin TIAN Xiaofeng CHENG Junsheng ZHANG Jishan State Key Laboratory for Advanced Metals and materials University of Science and Technology Beijing Beijing 100083 China international centre for materials physics Chinese Academy of Sciences Shenyang 110016 China National Engineering and Technology Research Center for Nonferrous Metals Composites General Research Institute for Nonferrous Metals Beijing 100088 China

NanocrystaUine Ni powders were successfully fabricated by mechanically milling at cryogenic temperature （cryomilling） with 1 wt.%Y2O3 particles. The experimental results have shown that the Ni grain size is reduced to 25 nm after 2 h of cryomilling in the presence of the Y2O3 particles. The cryomiUed Ni/Y2O3 powders can maintain their nanocrystalline structure up to 900℃, or 62% of the melting point of Ni. A bulk nanocrystalline Ni/Y2O3 material with a thermally stable grain size of approximately 100 nm was produced by cryomilling, cold isostatic pressing, followed by hot isostatic pressing. The microhardness of bulk nanocrystalline Ni/1wt.%Y2O3 is 315 DPH, which is two times as high as that of conventional Ni.

关键词： nanocrystalline mechanical milling nickel characterization

Chronological record of the Early Mesozoic underplating in the northern margin of North china—U-Pb chronometry of zircons in the Late Mesozoic andesite from Western Liaoning

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Progress in Natural Science:materials international 2007年第8期17卷 943-947页

作者： Shao ji'an~(1,2**) Zhang Hongfu~2 Liu Xiaoming~3 Li Zhitong~4 (1.School of Earth and Space sciences,Peking University,Beijing 100871,china 2.Institute of Geology and Geophysics and Key Laboratory of Mineral Resources,chinese academy of sciences,Beijing 100029,china 3.Key Laboratory of Continental Dynamics,Northwestern University,Xi'an 710069,china 4.Institute of Geology and Mineral Resources of shenyang,shenyang 110032,china) [a]School of Earth and Space sciences Peking University Beijing China [b]Laboratory of Mineral Resources Chinese Academy of Sciences Institute of Geology and Continental Dynamics Beijing China [c]Key Laboratory of Continental Dynamics Northwestern university Xi'an China [d]Institute of Geology and Mineral Resources of shenyang Shenyang China

Cathodoluminescence spectroscopic analysis of zircons in the uppermost sanukites of the early Cretaceous Yixian Forma- tion in Western Liaoning reveals zoning structures of the zircons in the volcanic rocks. LA-ICP-MS chronometry shows that the central part of the zircons is remnant zircon with a U-Pb dating of 254 Ma,which is consistent with the age of the Early Mesozoic underplating granulites,and that the periphery is zircon crystallizing out of the host magma with a U-Pb dating of 116 Ma,which is highly consistent with the Ar-Ar dating of the host volcanic *** of the clinopyroxenes xenocrystals in the sanukites are similar to those of the clinopyroxenes in the underplating granulites,indicating that the granulites accreted to the lower crust in the Early Mesozoic have been reformed and disrupted by the upwelling diapers of the asthenosphere and taken part in formation of the sanukites in the Late Mesozoic.

关键词： northern margin of North china Mesozoic volcanic rock U-Pb chronometry of zircon underplating granulite

Bulk metallic glasses formed by alloying the Cu_6Zr_5 cluster

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international Journal of Minerals,Metallurgy and materials 2007年第S1期15卷 39-42页

作者： Yanhui Li1), Qing Wang1), Jiang Wu1), Jianbing Qiang1), and Chuang Dong1,2) 1) State Key Lab of materials Modification, Dalian University of Technology, Dalian 116024, china 2) international Center of materials physics, chinese academy of sciences, shenyang 110016, china

The bulk metallic glass formation in the Cu-Zr-M ternary systems by alloying of a binary basic Cu6Zr5 cluster was inves- tigated, where M stands for Sn, Mo, Ta, Nb, Ag, Al and Ti. The Cu6Zr5 cluster is a capped Archimedean antiprism that characterizes the local structure of the Cu10Zr7 crystalline phase. This cluster composition almost superposes with Cu-Zr eutectic Cu0.56Zr0.44. A se- ries of alloys along the cluster line (Cu6Zr5)1-xMx were examined for their glass forming abilities. Alloy rods with a diameter of 3 mm were prepared by copper mould suction casting method and analyzed by XRD and thermal analysis. The Cu-Zr based bulk metallic glasses were discovered with minor Nb, Sn, Mo, Ta additions (≤2at%) and Al, Ti, Ag (8at%≤concentration≤9at%). The alloying mechanism was discussed in the light of atomic size, cluster-linking structure and electron concentration factors.

关键词： bulk metallic glasses cluster electron concentration atomic size minor-alloying Cu-Zr alloys

The biological effect and medical functions of the Infrared Rays

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chinese Journal of Biomedical Engineering(English Edition) 2001年第1期10卷 27-37页

作者： PANG Xiao-feng Institute of High-energy Electronics, University of Electronic Science and Technology of china,Chengdu 610054 and international centre for materialsphysics, chinese academy of sciences,shenyang 110015,china Institute of High-energy Electronics University of Electronic Science and Technology of ChinaChengdu 610054 and International centre for MaterialsphysicsChinese Academy of SciencesShenyang 110015China

The quantum vibrational energy-spectra including high excited states of the protein molecules have been calculated by new theory of bio-energy transport along the protein molecules and its dynamic equation, discrete nonlinear Schrodinger equation, appropriate to the protein molecules on the basis of the level of molecular structure. This energy-spectra obtained are basically consistent with the experimental values by infrared absorption and radiated measurement of person’s hands and laser-Raman spectrum from metabolically active ***.. From this energy-spectra we know that the infrared lights with (1-3)x1000nm and (5-7)x1000nm wavelength can be absorbed by the protein molecules in the living systems. In accordance with the non-linear theory of the bio-energy transport we know that the energy of the infrared light absorbed by the proteins can result in vibrations of amide-I in amino acids and can facilitate the bio-energy transport along the protein molecular chains from one place to other for the growth of living bodies. This processe is non-thermal. This is just non-thermal effect of the infrared lights. According to the mechanism we explained further the medical functions of the infrared lights absorbed.

关键词： Infrared light, bio-energy transport, energy-spectra, non-thermal biological effect, medical function