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Theoretical study on the reaction mechanism of(CH_3)_3CO+CO

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Science china chemistry 2005年第1期48卷 18-24页

作者： ZHAO Hongmei1,2.3, SUN Chengke1,4, ZHANG Rongchang3, XI Hongmin3 & LI Zonghe1 1. department of chemistry, Beijing {2. University, Beijing 100875, china 2. The Laboratory of Molecular Reaction Dynamics, Institute of chemistry, Chinese Academy of Sciences, Beijing 100080, china 3. department of chemistry, Beihua University, Jilin 132.13, china 4. department of chemistry, qujing {2. University, Yunnan 655000, china department of chemistry Beijing Normal University Beijing China The Laboratory of Molecular Reaction Dynamics Institute of Chemistry Chinese Academy of Sciences Beijing China department of chemistry Beihua University Jilin China department of chemistry Qujing Normal University Yunnan China

The reaction mechanism of (CH3)3CO with CO has been theoretically investigated using density-functional theory (DFT) calculations at B3LYP/6-31G* level. In order to get more reliable energy values the single-point energy is evaluated at CCSD (T)/6-31++G** level. The results show that the reaction is multi-channel and the reaction of (CH3)3CO radical with CO mostly produces (CH3)3C + CO2. The reaction could play a role in eliminating air pollution.

关键词： DFT, B3LYP, (CH3)3CO, radical.

Kinetic model of transesterification of diphenyl carbonate and 1,4-butyldiol

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Journal of Natural Gas chemistry 2010年第4期19卷 436-440页

作者： Liping Wang1,2.3,4,Bin Xiao1,2.4,Gongying Wang1,2.1.Chengdu Institute of Organic chemistry,Chinese Academy of Science,Chengdu 610041,Sichuan,china 2.Changzhou Key Laboratory of Green and Technology,Changzhou Institute of chemistry,Changzhou 2.3164,Jiangsu,china 3.department of chemistry,qujing normal college,qujing 655000,Yunnan,china 4.Graduate School of Chinese Academy of Science,Beijing 100039,china Chengdu Institute of Organic chemistry Chinese Academy of Science Chengdu 610041 Sichuan China Changzhou Key Laboratory of Green and Technology Changzhou Institute of Chemistry Changzhou 213164 Jiangsu China department of chemistry Qujing Normal College Qujing 655000 Yunnan China Graduate School of Chinese Academy of Science Beijing 100039 China

The transesterification of diphenyl carbonate （DPC） with 1,4-butyldiol （BD） was kinetically investigated in the presence of lithium acetate catalyst at 465 *** reaction was followed by the measurement of the quantity of phenol which was distilled from the *** experiments supported the assumption that the phenyl ester groups in DPC and phenyl hdroxybutyl carbonate （PHBH） had the same reactivity,and the transesterification obeyed first-order kinetics with respect to DPC and BD,and a rate equation was *** reaction rate was found to be first order with respect to the catalyst concentration as *** those data were incorporated in the rate equation,excellent agreement between calculated values and the observed ones was recognized over a wide range.

关键词： transesterification diphenyl carbonate 1,4-butyldiol lithium acetate kinetics

Approach to synthesis of novel chiral 3-chloro-2.5H)- furanone and its application in asymmetric reactions

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Chinese Science Bulletin 2000年第8期45卷 711-716页

作者： HUANG Hui & CHEN Qinghua1. department of chemistry, Tonghua Teacher’s {2., Tonghua 134002. china 2. department of chemistry, Beijing normal University, Beijing 100875, china department of chemistry Tonghua Teacher’s College Tonghua China department of chemistry Beijing Normal University Beijing China

The synthetic method of the novel chiral synthon, 5-/-menthyloxy-3-chloro-2.(5H)-furanone 5a and its application in asymmetric reactions were investigated. 5a is easily obtained in highly optical purity, and acts as a stable acceptor of Michael addition with oxygen nucleophiles in tandem double Michael addition / internal nucieophilic substitution to offer the spiro-cyclopropane derivative containing four stereogenic centers 8, which it is difficult to obtain by routine methods. The synthetic methods for 5a and 8 are reported in detail and the new compounds are identified on the basis of their analytical data and spectroscopic data, such as UV, IR, H NMR,13 C NMR, MS and elementary analysis. The absolute configuration of the interesting spiro-cyclopropanes, spiro [1-chloro-4-(/-menthyloxy)-5-oxo-6-oxa-biscyclo[3.1.0]hexane-2.3i(4’-/-menthyloxy-5’-/-menthyloxy- butyrolactone)] 8 was established by X-ray crystallography. This result can provide important synthetic strategy in synthesis of some complex

关键词： new chiral synthon. 5-l-menthyloxy-3-chloro-2.(5H)-furanone absolute configuration spiro-cyclopropane derivative containing multiple chiral centers.

Electrochemical characteristics of CoSn_x alloy composite anode for lithium-ion rechargeable batteries

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Rare Metals 2006年第Z1期25卷 369-373页

作者： GUO Hong ZHAO Hailei JIA Xidi QIU Weihua School of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083 China department of chemistry and Biology Qujing Normal University Qujing 655000 China School of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083 China School of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083 China School of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083 China

Nano/micro-scaled CoSnx alloy powders synthesized via carbothermal reduction at 800 ℃ with different compositions were characterized for anode materials in Li-ion battery. The synthesized spherical CoSnx particles show a loose nano/micro sized particle structural characteristic, which is apparently favorable for the improvement of cycling stability. The prepared CoSn3 alloy composite electrode exhibits a low initial irreversible capacity of ca.130 mAh·g-1 and a high specific capacity of ca.440 mAh·g-1 at constant current density of 100 mA·g-1. The relatively large particle size is considered to be the main reason for the lower irreversible capacity of CoSn3 electrode.

关键词： CoSnx composite anode materials carbothermal reduction Li-ion rechargeable batteries

Study of the Solutions for a Class of Nonlinear Dynamical Systems

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曲靖师范学院学报 2001年第3期 17-21页

作者： LIU Jun,CUI Ping,XUN Feng xian (department of Mathematics,qujing {2. college,qujing 655000,Yunnan, china)

In this paper,the boundedness and the stability of solution for a class of fourth order nonlinear differential equations are studied by using the method of Liapunov funtion. We obtain the sufficient conditions which g... 详细信息

关键词： nonlinear differential equation liapunov function asymptotic stability boundedness

Investigati on sonsimultaneous determination of silver and mercury in catalytic－ligandsub stitution reaction with stopped－flow technique calibrated by synergistic effect

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Journal of Environmental Sciences 1995年第4期7卷 414-421页

作者： Wang Jianhua , He Ronghuan(chemistry department of Yantai {2. college, Yantai 2.402. , china)

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关键词： kinetic stopped FIA synergistic catalytic coefficient simultaneous determination mercury(II) silver(I).

Spectral anomalies and spectral switches of partially coherent and polychromatic light diffracted at an aperture

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Science china(Physics,Mechanics & Astronomy) 2004年第1期47卷 24-35页

作者： Lü Baida1, 3 & PAN Liuzhan1, 2.1. Institute of Laser Physics and chemistry, Sichuan University, Chengdu 610064, china 2. {2. of Physics, Luoyang normal college, Luoyang 47102., china 3. State Key Laboratory of Laser Technology, Huazhong University of Science and Technology, Wuhan 430074, china Correspondence should be addressed to L Baida (email: badalu@***) Received July 10, 2.03 Institute of Laser Physics and chemistry Sichuan University Chengdu China State Key Laboratory of Laser Technology Huazhong University of Science and Technology Wuhan China department of Physics Luoyang Normal College Luoyang China

Based on the propagation theory of partially coherent light in the space-frequency domain, the anomalous spectral behavior and spectral switches in the far field of partially coherent and polychromatic light diffracted at an aperture are studied. It is shown that, as compared with spatially fully coherent and polychromatic light whose spectral anomalies are induced only by aperture diffraction, the spectral anomalies and spectral switches of partially coherent and polychromatic light depend on the aperture diffraction, spatial correlationβ and bandwidth of the original spectrum. Detailed numerical calculations are made to illustrate the behavior of spectral switches of partially coherent and polychromatic light, and the results for spatially fully coherent and polychromatic light are treated as a special case ofβ=1 and included in our theory.

关键词： spectral anomaly spectral switch partially coherent and polychromatic light far field aperture diffraction

Stability and Instability of Solution for a Class of Nonlinear Differential Equations

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曲靖师范学院学报 2000年第6期 5-6+10页

作者： Liu Jun 1 Cui ping 1 Xun Fengxian 1 Li Jinhua 2. (1 department of Mathematics,qujing {2. college,qujing 655000,Yunnan Province 2. The Sixth Middle School of Qilin District,qujing 655000,Yunnan Province)

In this paper,the stability and instability of solution for a class of nonlinear differential equations are studied.

关键词： Nonlinear Differential Equation Motive Stability Theory Stability

Knockdown of CD146 reduces the migration and proliferation of human endothelial cells

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Cell Research 2006年第3期16卷 313-318页

作者： Yanyong Kang~(1,3) Fengcai Wang~(1,2. Jing Feng~1 Dongling Yang~1 Xu Yang~3 Xiyun Yan~11 National Laboratory of Biomacromolecules,Institute of Biophysics,Chinese Academy of Science Beijing 100101,china 2.chemistry {2.,Anyang teacher's college,Anyang 455000,china 3 college of Life Science,Central china normal University,Wuhan 430079,china National Laboratory of Biomacromolecules Institute of Biophysics Chinese Academy of Science Beijing China college of Life Science Central China Normal University Wuhan China chemistry department Anyang teacher's College Anyang China

Our previous study has demonstrated that CD 146 molecule is a biomarker on vascular endothelium,which is involvedin angiogenesis and tumor *** the mechanism behind is not *** we have for the first time devel-oped a novel CD146 blockade system using CD146 siRNA to study its function on endothelial *** data showedthat CD146 siRNA specifically blocked the expression of CD146 on both mRNA and protein levels,leading to thesignificant suppression of HUVEC proliferation,adhesion and *** results demonstrate that CD146 playsa key role in vascular endothelial cell activity and angiogenesis,and CD146 siRNA can be used as a new inhibitor foranti-angiogenesis therapy.

关键词： small interfering RNA adhesion molecule CD 146 vascular endothelial cell