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THEORETICAL STUDIES ON NUCLEOPHILIC VINYLICHALIDE SUBSTITUTION

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Chinese Chemical Letters 1996年第7期7卷 631-634页

作者： Lin Jing YANG Xiao Yuan FU Shao Wen ZHANG (department of chemistry.Beijing Normal {2.. Beijing 00875) BEIJING NORMAL UNIV DEPT CHEMBEIJING 100875PEOPLES R CHINA

The reactions of vinyl fluoride, chloride, bromide and iodide with CN- and OH- were studied The trend of reactivity of vinyl halide with these two nucleophile is: fluoroethene < chloroethene approximate to bromoethene < iodoethene. The reaction of vinyl fluoride with CN- tends to be a multi-step process while the reactions of the other three vinyl halides with CN-, OH- are all single-step processes. The nucleophilicity of CN- is stronger than that of OH-.

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Effect of Trace Sc and Zr on the Mechanical Properties and Microstructure of A1 Alloy 2.18

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Journal of Materials Science & Technology 2000年第4期16卷 416-420页

作者： Kun YU, Songrui LI and Wenxian LI (department of Materials Science and Engineering, Central South university of Technology, Changsha 410083,{2.) department of Materials Science and Engineering Central South University of Technology Changsha 410083 China

An experimental 2.18(Al-Cu-Mg-Fe-Ni) alloy added with trace Sc and Zr was prepared by ingot metallurgy (IM) method. The aging behavior of the alloy was studied by Vickers hardness measurement at 2.0℃ and 300℃. and the tensile properties of alloy specimens were measured at 2.℃, 2.0℃, 2.0℃ and 300℃. The microstructure was observed by using optical microscope, SEM and TEM. It was found that the addition of Sc and Zr to 2.18 alloy resulted in a primary Al_3(Sc,Zr) phase which could refine the grain because it acts as nuclei of heterogeneous crystallization in the melt during solidification. The secondary Al_3(Sc,Zr) particles were full coherent with matrix and had obvious precipitation hardening effect. They also made the S' phase precipitate more homogeneous. So the strength of alloy increases at both ambient and elevated temperatures without a decrease of ductility. The ductile fracture of alloy occurs by microvoid nucleation, growth and coalescence, so the microvoid coalescence is the dominant fracture mechanism.

关键词： Sc Zr Effect of Trace Sc and Zr on the Mechanical Properties and Microstructure of A1 Alloy 2.18

AN ASSESSMENT OF LAND USE CHANGES IN FUQING COUNTYOF china USING REMOTE SENSING TECHNOLOGY

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Chinese Geographical Science 2002年第2期12卷 126-135页

作者： XU Han-qiu( department of Environmental and Resources Engineering, Fuzhou university, Fuzhou 350002. P. R.{2.) department of Environmental and Resources Engineering Fuzhou University Fuzhou 350002 P. R. China

Fuqing County of southeast china has witnessed significant land use changes during the last decade. Re mote sensing technology using multitemporal Landsat TM images was used to characterize land use types and to monitor land use changes in the county. Two TM scenes from 1991 and 1996 were used to cover the county and a five-year time period. Digital image processing was carried out for the remotely sensed data to produce classified images. The images were further processed using GIS software to generate GIS databases so that the data could be further spatially analyzed taking the advantages of the software. Land use change areas were determined by using the change detection technique. The comparison of the two classified TM images using the above technologies reveals that during the five study years, a large area of arable lands in the county has been lost and deforestation has taken place largely because of the dramatic in crease in built-up land and orchard. The conclusive statistical information is useful to understand the processes, causes and impacts of the land use changes in the county. The major driving force to the land use changes in the county ap peared to be the rapid economic development. The decision makers of the county have to pay more attention to the land use changes for the county’s sustainable development.

关键词： land use change remote sensing GIS driving force

金属胶束催化VIII:肟基铜(Ⅱ)配合物催化羧酸酯水解反应研究

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四川大学学报（自然科学版） 2004年第1期41卷 148-154页

作者：蒋炳英黄忠蒋维东谢飞胡常伟曾宪诚四川大学化学学院四川成都610064

合成并表征了单核和双核肟基铜(Ⅱ)配合物,研究了这两种配合物在不同胶束体系中催化羧酸酯水解的动力学,用相应的动力学模型处理得到了相关的动力学和热力学参数.研究结果表明,两种配合物在阳离子表面活性剂CTAB(十六烷基三甲基溴化铵)... 详细信息

合成并表征了单核和双核肟基铜(Ⅱ)配合物,研究了这两种配合物在不同胶束体系中催化羧酸酯水解的动力学,用相应的动力学模型处理得到了相关的动力学和热力学参数.研究结果表明,两种配合物在阳离子表面活性剂CTAB(十六烷基三甲基溴化铵)所生成的胶束溶液中催化PNPP(对硝基苯基α 吡啶甲酸酯)和PNPA(对硝基苯基乙酸酯)水解的活性高于在非离子表面活性剂胶束Brij35(聚氧乙烯(2.)十二烷基醚)中的催化作用;单核Cu(II)配合物在金属胶束相中催化PNPP水解和双核Cu(II)配合物在金属胶束相中催化PNPA水解的一级速率常数与它们在缓冲溶液中自发水解的速率常数相比,kN分别提高了大约2.747倍和32.14倍.

关键词：肟基配合物羧酸酯水解动力学处理

Analysis of clinical data of inpatients with primary hyperparathyroidism

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Analysis of clinical data of inpatients with primary hyperpa...

THE JOINT DISTRIBUTIONS OF SOME ACTUARIAL DIAGNOSTICS FOR THE JUMP-DIFFUSION RISK PROCESS

International Conference on Osteoporosis and Bone Research 2.08

作者： Xiaoyuan Gong Chunyan Lu Qin Wang Decai Chen department of Endocrinology West china Hospital {2. university chengdu china

＜正＞Objective:To summarize the clinical and laboratory presentations of primary hyperparathyroidism （PHPT） in West china Hospital, contributing to an increasing awareness about the disease. Methods:Reports of 63 p...

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来源： cnki会议评论

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Acta Mathematica Scientia 2010年第3期30卷 664-676页

作者：吕玉华吴荣徐润 department of Mathematics Qufu Normal University School of Mathematics Sciences and LPMC Nankai University

In this article, the joint distributions of several actuarial diagnostics which are important to insurers＇ running for the jump-diffusion risk process are examined. They include the ruin time, the time of the surplus process leaving zero ultimately （simply, the ultimately leaving-time）, the surplus immediately prior to ruin, the supreme profits before ruin, the supreme profits and deficit until it leaves zero ultimately and so on. The explicit expressions for their distributions are obtained mainly by the various properties of Levy process, such as the homogeneous strong Markov property and the spatial homogeneity property etc, moveover, the many properties for Brownian motion.

关键词： Jump-diffusion risk process Brownian motion time of ruin ultimately leaving-time homogeneous strong Markov property

A fiducial argument for generalized p-value

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Science china Mathematics 2007年第7期50卷 957-966页

作者： Xin-min LI~(1+) Xing-zhong XU~2.Guo-ying LI~3 1 Institute of Applied Mathematics,Shandong university of Technology,Zibo 2.5049,china 2.{2. of Mathematics,Beijing Institute of Technology,Beijing 100801,china 3 Academy of Mathematics and Systems Science,Chinese Academy of Sciences,Beijing 100800,china Institute of Applied Mathematics Shandong University of Technology Zibo 255049 China department of Mathematics Beijing Institute of Technology Beijing 100801 China Academy of Mathemtics Systems Science Chinese Academy of Sciences Beijing 100800 China

This paper provides a general method for constructing generalized p-value via the fiducial ***,the power properties of the generalized test are *** illustrations, the two-parameter exponential distribution and unbalan... 详细信息

关键词： fiducial distribution generalized p-value frequency property two-parameter exponential distribution variance component 62.03 62.15

Synthesis of Mn(Ⅲ) Complexes of New "Tailed" Porphyrins and Their Application as Carriers for PVC Membrane SCN-Anion-Selective Electrode

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Chinese Chemical Letters 1997年第11期8卷 997-999,0页

作者： Zhi Xian ZHOU Tie Sheng LI Yu Zhong WANG Yang Jie WU (department of chemistry, Zhengzhou {2., Zhengzhou 450052. department of chemistry Zhengzhou University Zhengzhou 450052 China

Three new 'tailed' porphyrins and their corresponding Mn(Ⅲ) metalloporphyrins were synthesized and characterized. The potentiometric response characteristics of the PVC membrane electrode based on the Mn(Ⅲ) comple... 详细信息

关键词： SCN PVC Complexes of New Porphyrins and Their Application as Carriers for PVC Membrane SCN-Anion-Selective Electrode Tailed

Synthesis,Crystal Structure and Studies on the Noncovalent Interaction of [Zn(BpheO)_(2.(phen)]_(2.·2.H_(3)OH·3H_(2.O

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Chemical Research in Chinese Universities 1997年第4期13卷 106-111页

作者： SHEN Liang * and SHENG Guo ding (department of chemistry, Hangzhou Teachers college, Hangzhou, 310012. GONG Yu qiu (department of chemistry, Hangzhou university, Hangzhou, 31002.) YU Kai bei (Analytical Center, chengdu Branch, Academia Sinica,

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关键词： Ternary complex 1,10 Phenanthroline N benzoyl DL phenylalaninate