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In-situ Synthesis and Formation Mechanism ofTiN-Al_2O_3/Al Composite

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Journal of Materials science & technology 1998年第1期14卷 77-79页

作者： Chunxiang CUP and Renjie WU (State Key lab. for MMCs, shanghai Jiaotong university, shanghai 200030, china)Jianran YAN and Guobin LI (Hebei Polytechnic university Tianjin 300132, china) shanghai Jiao Tong Univ State Key Lab MMCs Shanghai 200030 Peoples R China Hebei Polytech Univ Tianjin 300132 Peoples R China

The synthesis of TiN and Al2O3 by in situ injection of reactive nitrogen gas into molten Al alloys has been evaluated over the temperature range from 1000 to 1600℃. It is shown that TiN and Al2O3 can be formed in melt with nitrogen and surplus oxygen (in vacuum room of the induction furnace) as the reactive gases over 1000℃. Up to 2.1 wt pct Al2O3 and 5.2 wt pct of TiN in situ phases in an Al alloy has been formed in a range of size from 0.8 to 5 μm. The formation mechanism of TiN and Al2O3 is discussed in this paper.

关键词： Al Ti Res

Identification and genetic mapping of four novel genes that regulate leaf development in Arabidopsis

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Cell Research 2000年第4期10卷 325-335页

作者： SUN YUE WEI ZHANG FENG LING LI ying LI GUO TIAN LEI LIU HAI HUANG shanghai Institute of Plant Physiology, Chinese Academy of science, 300 Fenglin Road, shanghai 200032, china School of Life sciences, university of science and technology of china. 1shanghai Institute of Plant Physiology Chinese Academy of Science 300 Fenglin Road Shanghai 200032 China 1shanghai Institute of Plant Physiology Chinese Academy of Science 300 Fenglin Road Shanghai 200032 China 1shanghai Institute of Plant Physiology Chinese Academy of Science 300 Fenglin Road Shanghai 200032 China 2School of Life sciences University of Science and Technology of China. P.O.Box 4 Hefei Anhui 230027 China 1shanghai Institute of Plant Physiology Chinese Academy of Science 300 Fenglin Road Shanghai 200032 China 3shanghai Research Center of Life sciences Chinese Academy of Sciences 320 Yueyang Road Shanghai 200031 China

Molecular and genetic characterizations of mutants have led to a better understanding of many developmental processes in the model system Arabidopsis thaliana. However, the leaf development that is specific to plants has been little studied. With the aim of contributing to the genetic dissection of leaf development, we have performed a large-scare screening for mutants with abnormal leaves. Among a great number of leaf mutants we have generated by T-DNA and transposon tagging and ethylmethae sulfonate (EMS) mutagenesis, four independent mutant lines have been identified and studied genetically. Phenotypes of these mutant lines represent the defects of four novel nuclear genes designated LL1 (LOTUS LEAF 1), LL2 (LOTUS LEAF 2), URO (UPRIGHT ROSETTE), and EIL (ENVIRONT CONDITION INDUCED LESION). The phenotypic analysis indicates that these genes play important roles during leaf development. FOr the further genetic analysis of these genes and the map-based cloning of LL1 and LL2, we have mapped these genes to chromosome regions with an efficient and rapid mapping method.

关键词： Arabidopsis leaf mutant leaf development genetic mappin?

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基于衍生h指数期刊评价指标构建与实证研究

图书情报工作 2011年第14期55卷 144-148页

作者：刘颖华东理工大学图书馆上海200237

构建动态复合衍生h指数、即时复合衍生h指数和时间活跃型复合衍生h指数,结合《中国引文数据库》对19种图书情报学期刊进行实证分析,从期刊年代平均影响力、期刊影响力的即时性及期刊影响力的活跃性角度对期刊的学术影响进行评价。研究表... 详细信息

构建动态复合衍生h指数、即时复合衍生h指数和时间活跃型复合衍生h指数,结合《中国引文数据库》对19种图书情报学期刊进行实证分析,从期刊年代平均影响力、期刊影响力的即时性及期刊影响力的活跃性角度对期刊的学术影响进行评价。研究表明:三种指标体现期刊学术影响力的时间效应,反映出期刊刊载论文的深度及新颖度。

关键词：期刊评价 hmcy指数 hmciy指数 hmcay指数

Pareto-Nash混合策略下小世界网络中创新扩散模型仿真分析

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上海交通大学学报 2010年第3期44卷 345-348页

作者：李英蒋录全华东理工大学商学院上海200237 上海交通大学安泰经济与管理学院上海200052

采用基于代理(Agent)的复杂系统仿真方法,从微观层面研究了技术创新在小世界网络中的扩散问题,分析了Nash和Pareto 2种不同规则对扩散过程和扩散终态的影响.结果表明:在一定的成本系数取值范围内,采用Pareto规则的Agent获得的收益值高... 详细信息

采用基于代理(Agent)的复杂系统仿真方法,从微观层面研究了技术创新在小世界网络中的扩散问题,分析了Nash和Pareto 2种不同规则对扩散过程和扩散终态的影响.结果表明:在一定的成本系数取值范围内,采用Pareto规则的Agent获得的收益值高于采用Nash规则;同时,随着成本系数k的变化,2种规则带来的收益曲线中存在转折点,其出现在k=3.7处.

关键词：博弈代理小世界网络创新扩散

THEORETICAL AND EXPERIMENTAL INVESTIGATIONS OF W-BAND WHISPERING GALLERY MODE DIELECTRIC RESONATOR

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THEORETICAL AND EXPERIMENTAL INVESTIGATIONS OF W-BAND WHISPE...

pH-Dependent Stability of EGX, A Multi-functional Cellulase from Mollusca, Ampullaria crossean

International Conference on Millimeter Wave and far-Infrared technology

作者： Li, ying Xu, Shan-Hua Tong, Shan-Ling shanghai university of science and technology, china shanghai Univ of Sci & Technol Shanghai China

＜正＞ A mew type of dielectric resonator used in millimeter wave band is presented, which is called whispering gallery mode dielectric resonator （WGDR）. We also derived a method to calculate its resonant frequency and realized a simple band-stop filter in W-band with leuco sapphire mono-crystal dielectric resonator and rexolite dielectric waveguide. The results show that WGDR has many advantages.

关键词： Resonators

来源： cnki会议评论

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Acta Biochimica et Biophysica Sinica 2004年第9期36卷 603-608页

作者： Wen-ying LI2, Ji WANG1, Yan-Hong LI1, Ming DING1, Gen-Jun XU1,3, Lan-ying LIU2, and Fu-Kun ZHAO1,3* 1Key laboratory of Proteomics, Institute of Biochemistry and Cell Biology, shanghai Institutes for Biological sciences, the Chinese Academy of sciences,Graduate School of the Chinese Academy of sciences, shanghai 200031, china 2College of Life science, Jilin university, Changchun 130023, china College of Life science, Zhejiang university of science and technology, Hangzhou 310018, china Key laboratory ofProteomics Institute of Biochemistry and Cell BiologyShanghai Institutes for Biological Sciencesthe Chinese Academy of SciencesGraduate School of the Chinese Academy of SciencesShanghai 200031China

The cellulase activity and stability of EGX, a multi-functional cellulase previously purified from the mollusca Ampullaria crossean, was systematically studied under different pH. The pH induced con- formation and stability change of EGX have been investigated by using the intrinsic fluorescence, ANS fluorescence and CD spectrum. It has been found that the conformation and activity of this cellulase were strongly dependent on the pH. EGX was stable for both the enzyme activity and the conformation from pH 5.6 to pH 7.4. As shown by intrinsic and ANS fluorescence, no red shift of emission maximum occurred and a negligible intensity change was observed at pH 5.6–7.4. The activity of EGX remained about 80% in pH 5.6–7.4 and obviously decreased out of side the pH range. Urea-induced changes in EGX at pH 5.4 and pH 8.0 were measured by intrinsic fluorescence and CD spectrum. At pH 5.4, a significantly red shift of emission maximum occurred when the concentration of urea was 5 M compared to the concentration was 3 M at pH 8.0. The α-helix at pH 5.4 was 40.51% in the absence of urea and 31.04% in the presence of 4 M urea. At pH 8.0 the α-helix was 7.23% in the presence of 4 M urea. The data indicated that EGX was much susceptible to urea-induced unfolding at pH 8.0 and much stable at pH 5.4. The greater pH dependent stability of EGX may allow the enzyme to adequately catalyze the hydrolysis of cellulosic materials under natural or industrial extreme conditions.

关键词： multi-functional cellulase stability Ampullaria crossean fluorescence spectroscopy pH-dependent structural change CD spectrum

Convergence of Jamison-Type Weighted Sums of Pairwise Negatively Quadrant Dependent Random Variables

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Acta Mathematicae Applicatae Sinica 2002年第1期18卷 161-168页

作者： Han-ying LIANG, Zhi-jing Chen, Chun SUDepartment of Applied Mathematics, Tongji university, shanghai 200092, chinaDepartment of Statistics and Finance, university of science and technology of china, Hefei 230026, china Department of Applied Mathematics Tongji University Shanghai China Department of Statistics and Finance University of Science and Technology of China Hefei China

Under very general weight function, we discuss the convergence of Jamison-type weighted sums of pairwise negatively quadrant dependent (NQD) r.v.'s. The results on i.i.d. setting of [3] and [1] are extended and genera... 详细信息

关键词： Pairwise NQD sequence weighted sum convergence in probability almost sure convergence

Investigation on the Tribology of Co Implanted Stainless Steel Using Metal Vapor Vacuum Arc Ion Source

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Journal of Materials science & technology 2004年第3期20卷 265-268页

作者： Junxia GUO Xun CAI Qiulong CHEN Key lab for High Temperature Materials and Testing, shanghai Jiao Tong university, shanghai 200030, china lab. for High Temp. Mat. and Testing Shanghai Jiaotong Univ. Shanghai 200030 China

AISI 304 stainless steel was ion implanted with Co, and the tribological property on the surface of the stainless steelwas investigated. The Co ion implantation was carried out using a metal vapor vacuum arc (Mevva) broad-beam ionsource with an extraction voltage of 40 kV, implantation doses of 3×10^(17)/cm^2 and 5×10^(17)/cm^2, and ion currentdensities of 13, 22 and 32μA/cm^2. The results showed that the near-surface hardness of Co-implanted stainless steelsample was increased by 50% or more, and it increased with increasing ion current density at first and then declined.The friction coefficient decreased from 0.74 to 0.20 after Co implantation. The wear rate after Co implantationreduced by 25% or more as compared to the unimplanted sample. The wear rate initially decreased with increasingion current density and then an increase was observed. Within the range of experimental parameters, there existsa critical ion current density for the Co-implanted stainless steel, at which the wear rate decreased with increasingretained dose, going through a minimum and then increased. The critical ion current density in this paper is about22μA/cm^2.

关键词： Tribology Metal vapor vacuum arc Cobalt Implanted stainless steel

The maximal rates and minimal decoding delay of more general complex orthogonal designs

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science china(Information sciences) 2010年第9期53卷 1826-1832页

作者： LI Yuan,KAN HaiBin*,YUAN Chen & MA HuanFei The shanghai Key lab of Intelligent Information Processing,School of Computer science,Fudan university,shanghai 200433,china 1. The shanghai Key lab of Intelligent Information Processing School of Computer Science Fudan University Shanghai 200433 China

Space-time block codes based on complex orthogonal design have been widely investigated for their remarkable *** this paper,we propose a definition of more general complex orthogonal designs,which permits arbitrary complex factor with unit modulus in each *** prove that the maximal rate is still (m+1)/2m for n = 2m or 2m-1 antennas and minimal delay is also lower-bounded by(2m/(m-1)).Thus,allowing complex factor with unit modulus in each entry will not improve the main performance criterion of space-time block codes.

关键词： space-time block codes complex orthogonal design more general complex orthogonal design maximal rates minimal delays