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In-situ growth and photoluminescence of β-Ga_2._3 cone-like nanowires on the surface of Ga substrates

science china(Technological sciences) 2009年第6期52卷 1712-1721页

作者： LIU RuiNi1,YANG HeQing1,ZHANG RuiGang1,DONG Hongxing1,CHEN xiaoBo1,LI Li1,ZHANG LiHui1,MA JunHu1 & ZHENG HaiRong2.1 Key Laboratory of Macromolecular science of shaanxi Province,{2. of Chemistry and materials science,shaanxi Normal university,xi’an 710062.china 2.school of Physics & Information technology,shaanxi Normal university,xi’an 710062.china Key Laboratory of Macromolecular science of shaanxi Province School of Chemistry and Materials Science Shaanxi Normal University Xi’an China school of Physics & Information technology Shaanxi Normal University Xi’an China

β-Ga2.3 cone-like nanowires have been in-situ grown on the surface of gallium grains and films by heating gallium substrates at 750-1000℃ for 2. in *** controllable synthesis of β-Ga2.3 nano-wires with different diameters and lengths was achieved by adjusting the heating temperature and *** as-synthesized products were characterized by means of X-ray diffraction,scanning electron mi-croscopy and transmission electron *** results showed that the β-Ga2.3 nanowires are single crystalline with a monoclinic structure and have a controllable diameter and length in the range of 30-100nm and 0.5-1.5μm,respectively.A possible mechanism was also proposed to account for the formation of β-Ga2.3 cone-like *** spectra of the β-Ga2.3 nanowires obtained at different temperatures were measured at room temperature,and a strong blue photolumi-nescence with peaks at 430 and 460nm and a weak red photoluminescence with peak at 713nm were *** blue light emission intensity decreases with increasing the reaction temperature,how-ever,the red light emission intensity hardly *** blue and red light emissions originate from the recombination of an electron on an oxygen vacancy with a hole on a gallium-oxygen vacancy pair and the nitrogen dopants,etc.,respectively.

关键词： β-Ga2.3 cone-like nanowires photoluminescence in-situ growth

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Quasi-nano wear mechanism under repeated impact contact loading

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science china(Technological sciences) 2010年第6期53卷 1583-1589页

作者： ZHU JinHua1,REN xiangHong1,2.ZHANG JianJun1,3,XU YunHua1,3 & LU Zhengxin1,4 1 State Key Laboratory for Mechanical Behavior of materials,xi’an Jiaotong university,xi’an 710049,{2. 2.xi’an Research Institute of High-tech,xi’an 71002.,{2. 3 school of materials science and Engineering,xi’an university of Architecture and technology,xi’an 710055,{2. 4 school of materials science and Engineering,xi’an university of technology,xi’an 710049,{2. State Key Laboratory for Mechanical Behavior of materials Xi’an Jiaotong University Xi’an China xi’an Research Institute of High-tech Xi’an China school of materials {2. and Engineering Xi’an University of Architecture and Technology Xi’an China school of materials {2. and Engineering Xi’an University of Technology Xi’an China

A new quasi-nano wear mechanism (QNWM) has been proposed in this paper based on the facts of wear curve turning under high energy impact contact *** characteristic is that the wear rate of QNWM is only 1/10-1/3 that of delamination mechanism at the same energy *** diameters of wear debris and pits on the worn surfaces fall into the quasi-nanometer scale (about 50-12. nm).The necessary and sufficient conditions,which bring about the QNWM,are:(i) the nano-structure (nano-crystalline + amorphous phase) in impact contact surface layer has formed by the intensive impact strain;(ii) the delamination wear cracking in sub-surface layer must be restrained;(iii) the microcracks of QNWM are produced in amorphous phase of surface nano-structure layer rather than in nano-crystalline.

关键词： impact wear quasi-nano wear mechanism delamination wear mechanism nano-structure

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Analysis of Microstructure and Orientation in X80 Line Pipe Steels

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Journal of Iron and Steel Research International 2011年第S1期18卷 664-668页

作者： JI Ling-kang 1,2.LI Yang 2.3,MENG Li 3,LI He-lin 2.(1.school of Material science and Engineering,xi’an Jiaotong {2.,xi’an 710049,shaanxi,china 2.CNPC Tubular Goods Research Institute,xi’an 710065,shaanxi,china 3.school of Material science and Engineering,{2. of science and technology Beijing,Beijing 100083,china) xi An Jiao Tong Univ Sch Mat Sci & Engn Xian 710049 Shaanxi Peoples R China CNPC Tubular Goods Res Inst Xian 710065 Shaanxi Peoples R China Univ Sci & Technol Beijing Sch Mat Sci & Engn Beijing 100083 Peoples R China

Microstructures in X80 line pipe were classified by SEM *** experimental results showed that the microstructures in X 80 line pipe steels were complicated consisting of polygonal ferrite,bainite and acicular *** relation within acicular ferrite was investigated systematically by means of *** sub-structures were observed maximum in acicular ferrite which gives high strength and high toughness to line pipe *** K-S orientation relation was generally observed between acicular ferrite and austenite during phase *** low energy CSL boundary characterized by Σ3 orientation relation according to Brandon criterion appeared with higher probability,which was benefit to improve the mechanical properties of line pipe *** orientations or texture of initial austenite grains could be deduced based on the Σ3 orientation relationship of acicular ferrite variants.

关键词： acicular ferrite EBSD K-S orientation relation TMCP

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A new ordered phase forming during ageing in Cu-Ti alloys

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Chinese science Bulletin 1997年第19期42卷 1671-1672页

作者： WEI Yinghui and WANG xiaotian1. Department of materials science, Taiyuan {2. of technology, Taiyuan 03002., china 2. College of materials science, xi’an Jiaotong {2., xi’an 710049, china Ion Beam Laboratory Shanghai Institute of Metallurgy Chinese Academy of Sciences Shanghai 200050 China

AGE-hardened Cu-Ti has been an important alloy of investigation in the field of continuousphase transformation due to its complicated transformation processes which involve short rangeordering (SRO), spinodal decomposition (SD), long range ordering (LRO), etc. So far, ithas been a controversial topic whether each process exists, and in what sequence they pro-ceed.

关键词： Ti Cu A new ordered phase forming during ageing in Cu-Ti alloys

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Structure and Properties of BaFe_(12.O_(19) Coated Fly Ash Cenospheres by Sol-Gel Process

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Journal of Wuhan university of technology({2. science) 2006年第3期21卷 129-131页

作者：曾爱香 Department of materials science and {2. Changsha University of Science and TechnologyChangsha 410076ChinaState Kay Laboratry of Die and Mould Technology Huazhong University of Science and TechnologyWuhan 430074China

Thin films of barium hexaferrite were prepared on fly ash cenosphere particles by the sol-gel method using Fe（ NO3 ）3 ·9H2., Ba（ NO3 ）2.and citric acid as raw materials. The prepared films were characterized by differential thermal and thermogravimetric analysis （DTA-TG）, X-ray diffraction analysis （XRD）, scanning electron microscopy （SEM）, energy dispersive spectroscopy （EDX）, X-ray photoelectron spectroscopy （XPS）, and vibrating sample magnetometry . The magnetic and structural properties of barium hexaferrite coated cenosphere particles were also studied. The experimental results show that even and continual barium hexaferrite coatings were prepared on fly ash cenospheres , and the magnetic conductivity was imparted to these non-conducting oxide ceramic particles. The low density barium hexaferrite coated cenosphere particles may be atilized for manufacturing microwave absorbing materials.

关键词： barium hexaferrite coating fly ash cenosphere particles sol-gel

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Sol-gel Preparation and Infrared Radiation Property of Boron-substituted Cordierite Glass-ceramics

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Journal of materials science & {2. 2010年第5期26卷 445-448页

作者： Shuming Wang and Fenghua Kuang school of materials {2. and Engineering,university of {2. & technology Beijing,Beijing 100083,china school of materials {2. and Engineering University of Science & Technology Beijing Beijing 100083 China

Boron for aluminum substitution in the cordierite structure has been examined by sol-gel preparation of different samples along the compositional junction Mg2.l4-xBxSi5O18 with x=0,0.5,1,*** increasing the x value from 0 to 1.5 the crystallization behavior changed *** amount B2.3 doping can promote the sintering of amorphous cordierite gel,effectively restrain the precipitation of μ-cordierite and enhance the crystallization of α-*** substitution of B3＋ for Al3＋ in cordierite crystal structure can effectively improve the near-infrared spectral emissivity of this cordierite based glass-ceramics.

关键词： Sol-gel Glass-ceramics Infrared radiation B3+ substitution Solid solution

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(2.n)secret sharing scheme for gray and color images based on Boolean operation

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science china(Information sciences) 2012年第5期55卷 1151-1161页

作者： DONG Lin 1,WANG DaoShun 1,LI ShunDong 2.& DAI YiQi 1 1 Department of Computer science and technology,Tsinghua {2.,Beijing 100084,china 2.school of Computer science,shaanxi Normal {2.,xi'an 710062.china Department of Computer science and technology Tsinghua University Beijing China school of Computer science Shaanxi Normal University Xi’an China

Traditional secret sharing (SS) schemes can reconstruct the secret precisely,but have high com-putation *** secret sharing (VSS) schemes use human visual system to reconstruct the secret without cryptographic computation,but have pixel expansion and loss of *** et *** a (2.n)-SS scheme for binary images based on Boolean operation,which has low computation complexity,no pixel expansion and the contrast is 1/*** this paper,we first construct an r runs (2.n)-SS scheme to improve the contrast of Wang et al.'s binary (2.n)-SS *** we present two approaches to construct r runs (2.n)-SS schemes for grayscale image and color *** two approaches are both based on Boolean operation,while one approach uses halftone technology and the other uses bit level *** proposed schemes have low computation complexity and almost ideal contrast.

关键词： secret sharing scheme Boolean operation halftone contrast

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Chemical Extraction Preparation of Delithiated Cathode materials of Li-ion Battery

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Journal of Wuhan university of technology({2. science) 2009年第6期24卷 863-866页

作者：闫时建 school of materials {2. and Engineering Taiyuan University of Science and Technology

A method of conventional chemical reaction to prepare delithiated cathode materials of Li-ion battery was introduced. The cathode material of Li-ion battery was mixed with oxidizing agent Na2.2.8 in water solution, and the solution was stirred continuously to make the chemical reaction proceed sufficiently, then the reaction product was filtered and finally the insoluble delithiated cathode material was obtained. A series of tests were conducted to verify the composition, crystal structure and electrochemical property of the delithiated cathode materials were all desirable. This method overcomes the shortcomings of battery charging preparation and chemical extraction preparation employing other oxidizing agents.

关键词： chemical extraction delithiated cathode material Li-ion battery

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Dislocation Densites of Deformed Steel Sheets Based on Positron Annihilation

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International Journal of Minerals,Metallurgy and materials 1998年第1期12卷 47-50页

作者： Yonglin Kang xianjin Wang (materials science and Engineering {2., university of science and technology Beijing, Beijing 100083, china) materials science and Engineering {2. University of Science and Technology Beijing Beijing 100083 China

The variation regularity of dislocation densites of some deformed steel sheets under three kinds of strainpaths as uniaxial tension, plane strain and equal biaxial stretching was investigated by means of positron lifetimespectrum and Doppler-broadening techniques. The results show that the increasing rate of dislocation densites isrelated to the plastic strain path. A relationship between the increasing rate of micro-defects, macro-instability andforming limits during the process of steel sheet forming was got based on analyzing the mechanism of dislocationdensity increasing under different stress-strain condihons.

关键词： positron annihilation dislocation steel sheet strain path

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Effect of Nd_2.e_(14)B/α-Fe Nanocomposite Permanent Magnets with a Combined Co and Nb Additions

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Journal of Wuhan university of technology({2. science) 2009年第5期24卷 725-727页

作者：马瑞 school of materials {2. and Metallurgy Engineering Guizhou University

Influence of Co＋Nb on the Nd8Fe82.o3Nb1B6 nanocomposite magnets was investigated by adding Co element combined with Nb element. Results show that the high temperature stability of two phases is increased. Adding Co＋Nb could improve the glass forming ability of the alloy, reduce the size of grains, increase the exchange coupling ability of two phases, and obviously increase the magnetic properties of the alloy. The optimal magnetic properties are Br=1.14 T, Hcj=32. kA/m, （BH）max=109.3 kJ/m^3

关键词： nanocomposite permanent magnets glass forming ability exchange coupling ability magnetic properties

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