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Growth of Carbon Encapsulated Long Nickel Nanorods on Bulk Nickel Substrate

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Journal of Wuhan University of Technology(Materials Science) 2011年第1期26卷 28-32页

作者：宾晓蓓 College of Resources & Environment Engineering Wuhan University of Technology

Carbon nanotube encapsulated nickel nanorods were catalytic grown via pyrolysis of oil on a bulk nickel wire substrate. X-ray diffraction, scanning electron microscopy, high-resolution transmission electron microscopy and Raman spectroscopy were employed to characterize the as-prepared sample. The results show that, carbon nanotubes possess several microns in length, the filled metallic nickel nanorods with a uniform diameter of 35 nm were tightly encapsulated by the carbon capsules. The detailed formation mechanism for the carbon nanotubes encapsulated nickel nanorods were discussed briefly.

关键词： carbon nanotube nickel nanorod pyrolysis core-shell

INFLUENCE OF Pb ON THE STRUCTURAL PROPERTIES OF 2.12.SINGLE CRYSTALS IN Bi-Sr-Ca-Cu-O SYSTEM

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低温物理学报 1993年第4期 284-289页

作者： Wan Xianqin Cui Changgeng Ren ZhifengInstitrte of Physics, chinese academy of sciences, beijing 100080

The effect of Pb on the structural properties is studied in PbxBi2.r2.aCu2.y single crystals by electron diffraction and EDX elemental analysis. Results show: a/b increases with increasing Pb content, and the structural modulation changes following 4,7b-mixed (4. 7b, 8. 556)-disappeared. There is a phase transition happened at Pb content about 10% (Elemental percentage calculation only contains four elements of Bi, Sr, Ca, Pb. The content is in atom percentage. ) A new phase which has 2. and 1. 5b superstructure is observed in high Pb concentration region.

关键词： Pb INFLUENCE OF Pb ON THE STRUCTURAL PROPERTIES OF 2.12.SINGLE CRYSTALS IN Bi-Sr-Ca-Cu-O SYSTEM Sr Bi Cu Ca

Effect of Dissolved CO_2.and Tetrahydrofuran on the Polymerization of Acrylic Acid

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chinese Chemical Letters 1999年第7期10卷 601-602页

作者： Qun XU Bu Xing HAN Hai Ke YAN(Institute of Chemistry. chinese academy of sciences. beijing 100080) chinese Acad Sci Inst Chem Beijing 100080 Peoples R China

The polymerization of acrylic acid (AA) with dissolved carbon dioxide and tetrahydrofuran (THF) in the monomer is studied. Viscosity measurement. differential scanning calorimetry (DSC). and scanning electron microscopy (SEM) indicate that the conccntration of tctrahydrofuran has pronounced effect on the molecular weight (Mn). glass transition temperature (Tg). and the morphology of the product.

关键词： Polymerization acrylic acid tetrahydrofuran supercritical carbon dioxide

In Situ Synthesis of Nanocrystalline Intel-metallic Compound Layer during Surface Mechanical Attrition Treatment of Zirconium

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材料热处理学报 2004年第5期 1242-1246页

作者： SUN Cai-yun', Xffi Ji-jia ', WU Xiao-lei', HONG You-shi', LIU Gang \ LU Jian3, LU Ke2.1. State Key laboratory of Nonlinear Mechanics, Institute of Mechanics, chinese academy of sciences,{2., People's Republic of china 2. Shenyang National laboratory for Materials sciences, Institute of Metal Research, chinese academy of sciences, Shenyang 110016, People's Republic of china 3. LASMIS, University of Technical of Troyes, 10000, Troyes, France

The surface mechanical attrition treatment (SMAT) technique was developed to synthesize a nanocrystalline (NC) layer on the surface of metallic materials for upgrading their overall properties and performance. In this paper, by means of SMAT to a pure zirconium plate at the room temperature, repetitive multidirectional peening of steel shots (composition (wt%): 1C, ***, base Fe) severely deformed the surface layer. A NC surface layer consisting of the intermetallic compound FeCr was fabricated on the surface of the zirconium. The microstructure characterization of the surface layer was performed by using X-ray diffraction analysis, optical microscopy, scanning and transmission electron microscopy observations. The NC surface layer was about 2. urn thick and consisted of the intermetallic compound FeCr with an average grain size of 2.±10 nm. The deformation-induced fast diffusion of Fe and Cr from the steel shots into Zr occurred during SMAT, leading to the formation of intermetallic compound. In addition, the NC surface layer exhibited an ultrahigh nanohardness of 10.2.GPa.

关键词： nanocrystalline intermetallic compound surface layer deformation diffusion

A Self-consistent Calculation and an Anisotropic Wavelength Cut off Energy of Spin-wave Spectrumin Magnetic Tunnel Junctions

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Journal of Materials Science & Technology 2001年第2期17卷 197-202页

作者： Xiufeng HAN State Key laboratory of Magnetism, Institute of Physics, chinese academy of sciences,{2., china Terunobu Miyazaki Department of Applied Physics, Graduate School of Engineering, Tohoku University, Aoba-yama 08, Sendai 980-8579, Japa chinese Acad Sci Inst Phys State Key Lab Magnetism Beijing 100080 Peoples R China Tohoku Univ Grad Sch Engn Dept Appl Phys Sendai Miyagi 9808579 Japan

Temperature dependence of tunnel magnetoresistance (TMR) ratio, resistance, and coercivity from 4.2.K to room temperature (RT), applied de bias voltage dependence of the TMR ratio and resistances at 4.2.K and RT, tunnel current I and dynamic conductance dI/dV as functions of the de bias voltage at 4.2.K, and inelastic electron tunneling (IET) spectroscopy, d(2.I/dV(2. versus V, at 4.2.K for a tunnel junction of Ta(5 nm)/Ni79Fe2.(2. nm)/Ir2.Mn78(12.nm)/Co75Fe2.(4 nm)/Al(0.8 nm)-oxide/Co75Fe2.(4 nm)/Ni79Fe2.(2. nm)/Ta(5 nm) were systematically investigated. High TMR ratio of 59.2. at 4.2.K and 41.3% at RT were observed for this junction after annealing at 2.5 degreesC for an hour. The temperature dependence of TMR ratio and resistances from 4.2.to 300 K at 1.0 mV bias and the de bias voltage dependence of TMR ratio at 4.2.K from 0 to 80 mV can be evaluated by a comparison of self-consistent calculations with the experimental data based on the magnon-assisted inelastic excitation model and theory. An anisotropic wavelength cutoff energy of spin-wave spectrum in magnetic tunnel junctions (MTJs) was suggested, which is necessary for self-consistent calculations, based on a series of IET spectra observed in the MTJs.

关键词： off TMR A Self-consistent Calculation and an Anisotropic Wavelength Cut Energy of Spin-wave Spectrumin Magnetic Tunnel Junctions wave Figure than

Competitive Adsorption between Bovine Serum Albumin and Collagen Observed by Atomic Force Microscope

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chinese Chemical Letters 2004年第12期15卷 1465-1468页

作者： Yong YU Pei Qing YING Gang JIN National Microgravity Lab,Institute of Mechanics,chinese academy of {2., beijing 100080 National Microgravity Lab Institute of MechanicsChinese Academy of SciencesBeijing 100080

Atomic force microscopy (AFM) was used to study the competitive adsorption betweenbovine serum albumin (BSA) and type Ⅰ collagen on hydrophilic and hydrophobic silicon wafers.BSA showed a grain shape and the type Ⅰ collagen displayed fibril-like molecules with relativelyhomogeneous height and width, characterized with clear twisting (helical formation). These AFMimages illustrated that quite a lot of type Ⅰ collagen appeared in the adsorption layer on hydrophilicsurface in a competitive adsorption state, but the adsorption of BSA was more preponderant than thatof type Ⅰ collagen on hydrophobic silicon wafer surface. The experiments showed that theinfluence of BSA on type Ⅰ collagen adsorption on hydrophilic surface was less than that onhydrophobic surface.

关键词： Atomic force microscope protein competitive adsorption collagen bovine serum albumin.

MORPHOLOGICAL STUDY ON THE ORIENTED CHITOSAN FILM OBTAINED FROM PRE-SHEARED LIQUID CRYSTALLINE SOLUTION IN DICHLOROACETIC ACID

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chinese Journal of Polymer Science 2001年第4期19卷 385-390页

作者： Zhong-ming Hu Li-heng Wu Da-cheng Wu Shou-xi Chen State Key laboratory of Polymer Physics and Chemistry, Center for Molecular Science, Institute of Chemistry chinese academy of sciences,{2., china china Textile academy beijing 10002., china Textile College, Sichuan University Chengdu 610065, china china Text Acad Beijing 100025 Peoples R China chinese Acad Sci Inst Chem Ctr Mol Sci State Key Lab Polymer Phys & Chem Beijing 100080 Peoples R China Sichuan Univ Coll Text Chengdu 610065 Peoples R China

The oriented chitosan films obtained from pre-sheared liquid crystalline chitosan/dichloroacetic acid (DCA) solutions were studied by means of polarized optical microscopy (POM), scanning electron microscopy (SEM), infra-red dichroism technique and wide angle X-ray diffraction (WAXD). The sheer induced band texture in the film was found to correspond to the sinusoidal fibrillar microstructure along the shearing direction on the basis of POM and SEM observations. The sinusoidal fibril was found to be lying within the film plane. The model of chitosan molecular orientation in the pre-sheared film with band texture can be established assuming that the main chain orients in the shearing direction and the side group is perpendicular to the shearing direction. The WAXD azimuthal scanning at 2.theta = 2. degrees indicates that the (002. plane orients perpendicular to the shearing direction.

关键词： chitosan morphology orientation shear induced band texture liquid crystalline solution

electron-mediated ferromagnetism in Fe-doped InP:Theory and experiment

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chinese Physics B 2012年第9期21卷 484-488页

作者：董珊朱峰 State Key laboratory for Superlattices and Microstructures Institute of SemiconductorsChinese Academy of Sciences

We report on the electron-mediated ferromagnetism in Fe-doped InP from both first-principles calculations andexperiments. Theoretically, based on the spin-polarized density functional theory within the Heyd-Scuseria-Ernzerhof （HSE03） approach, we systematically investigate the magnetic properties of Fe-doped InP and predict the existence of electron-mediated ferromagnetism. Experimentally, by diffusing Fe into the n-type InP wafer with thermal annealing at 800 ℃, we observe room-temperature ferromagnetism in InP：Fe, which is in agreement with the theoretical prediction.

关键词： erromagnetism Fe-doped InP first-principles calculations

Wear Behavior of Cu Matrix Composites Reinforced with Mixture of Carbon and Carbon Nanotubes

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Journal of Wuhan University of Technology(Materials Science) 2009年第2期24卷 254-257页

作者：姜金龙 School of Science Lanzhou University of Technology State Key laboratory of Solid Lubrication Lanzhou Institute of Chemical Physics Chinese Academy of Sciences

In order to improve wear resistance and decrease the cost, carbon and carbon nanotubes reinforced copper matrix composites were fabricated by the power metallurgy method. The effects of carbon （carbon and carbon nanotubes） volume fraction and applied load on the friction coefficient and wear rate under dry sliding of the composites were investigated at room temperature. By scanning electron microscopy （SEM）, the worn surfaces and debris were observed, and wear mechanism was also analyzed and discussed. The experimental wear process consists of the run-in, steady wear and severe wear process with the increasing of sliding distance. Both the friction coefficient and wear rate of the composites first decrease and then increase with the increasing of carbon volume fraction. The minimum friction coefficient and wear rate are obtained when carbon is 4.0vo1%. The wear mechanisms of the composites change from the adhesive wear and delamination wear to abrasive wear with the increasing of carbon volume fraction.

关键词： C/Cu matrix composite power metallurgy wear behavior