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A local spin evaluation into the active site models of [2.e2.] ferrodoxin [Fe_2._2.SR)_4]^(2.) (R=-H, -CH_3)

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Science china chemistry 2007年第3期50卷 327-334页

作者： WEI JiChong1,2. WANG Yan3 & JU GuanZhi2.3 1 department of chemistry, Hainan Normal University, Haikou 571158,{2. 2.State Key Laboratory of Theoretical and Computational chemistry, jilin University, changchun 13002.,{2. 3 department of chemistry, Nanjing University, Nanjing 2.0093,{2. 1. department of chemistry Hainan Normal University Haikou 571158 China 2. State Key Laboratory of Theoretical and Computational chemistry Jilin University Changchun 130023 China 3. department of chemistry Nanjing University Nanjing 210093 China

To test the feasibility of local spin theory of Davidson and Clark for ferrodoxin clusters, the models [Fe2.2.SR)4]2. (R=-H, -CH3) are chosen for evaluation. This purpose is realized by calculating the local spin expectation values , 2.>, and mA and discussing the connection between these expected values and the Heisenberg spin model (HSM) and the Noodleman broken-symmetry approach. In practical calculation, the spin-unrestricted Hartree-Fock (UHF) and spin-polarized density functional theory (DFT) are used and the calculational qualities of these two methods are also discussed. In addition, the theoretical magnetic coupling constants JAB of these models are calculated by various computational schemes for comparison with both theoretical and experimental results previously reported.

关键词： local spin iron-sulfur protein model density function theory magnetic coupling constant

State feedback stabilization of discrete linear switching systems subject to nonsymmetrical state and control bounds

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控制理论与应用（英文版） 2012年第2期10卷 216-222页

作者： Zhiyuan LIU 1 , Guowei FAN 1 , Hong CHEN 2.1.department of Control Science and Engineering, Harbin Institute of Technology, Harbin Heilongjiang 150001, china {2. of Control Science and Engineering, jilin University, changchun jilin 13002., china department of Control Science and Engineering Harbin Institute of Technology Harbin Heilongjiang China department of Control Science and Engineering Jilin University Changchun Jilin China

Stabilization problem of discrete-time linear switching systems with bounds on the state and control input is solved in this paper. First, the synthesis of state feedback controllers that ensure the stability of closed-loop switching systems is studied under a sufficient condition. By using the idea of positive invariance, a stabilizing controller design methodology is proposed. Based on these results, the convergence rate problem is also discussed. A state feedback controller that guarantees the optimal convergence rate of closed-loop switching systems is obtained via optimization. Finally, an example made up of two subsystems is studied to show the application of our method.

关键词： Switching systems Constraints Stabilization problem Convergence rate problem

FLUORESCENCE　STUDIES　ON　SELF－ASSEMBLING　BEHAVIOR　OF　AMPHIPHILES　WITH　NAPHALENE－1，5－DIOXY　GROUP

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Chinese Chemical Letters 1996年第8期7卷 735-736页

作者： Guo Wen LI Ying Qiu LIANG2.Institute of Theoretical chemistry, jilin University, {2., 13002.)(department of chemistry, Nanjing University, Nanjing 2.0093) Institute of Theoretical chemistry Jilin University Changchun 130023 department of chemistry Nanjing University Nanjing 210093

Fluorescene Spectra in dilute aqueous solution of a series of single chain amphiphileswith an interposed naphthalene-1,5-dioxy group were studied to elucidate the characteristic selfassembling behavior. which indicate... 详细信息

关键词： STABLE BILAYER ASSEMBLIES SINGLE-CHAIN AMPHIPHILES DILUTE AQUEOUS-SOLUTION

Ship-in-bottle formation of Ru_3(CO)_(12. in NaY zeolite

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Chinese Journal of chemistry 1994年第3期12卷 258-264页

作者： XIAO, Feng-Shou XU, Ru-Ren HE, Ya-Nan department of chemistry, {2. University, changchun, {2. 13002., china department of chemistry Jilin University Changchun Jilin 130023 China

NaY zeolite entrapped Ru3(CO)12.cluster has been synthesized from RuCl3 ion-exchanged NaY, which is well characterized by IR and Raman spectroscopies and CO chemisorp-tion. When the Ru3+/NaY sample is heated from 2.8 K to 393 K for 2. h and for 10 h at 393 K, the sample colour changes from dark to brown-yellow. The in situ infrared spectrum exhibits absorption bands at 2.30, 2.64, 2.40, 2.17, 1990, 1953 and 192. cm-1. The bands at 2.30 cm-1 arises from the Runm+(CO)l m =1-3;n = 1 - 3; l = 1-12.. The bands at 2.64, 2.40, 2.17 and 1990 cm-1 are proposed to be associated with the Ru3(CO)12.NaY, which are close to Ru3(CO)12.crystalline. Furthermore, the Raman results provide bands at 150 and 185 cm-1, which can be attributed to Ru-Ru bonds of the sample as in the case of Ru3(CO)12.crystalline, for which the A1' Ru-Ru stretching mode is assigned to 185 cm-1 and E1' Ru-Ru stretching mode is assigned to a band at 150 cm-1, respectively. CO chemisorption of [Ru3]/NaY gives a CO/Ru ratio of 3.85, which is similar to the stoichiometry of Ru3(CO)12.

关键词： Cluster ruthenium carbonyl NaY zeolite infrared Raman CO chemisorption.

Surface effects of monolayer-protected gold nanoparticles on the redox reactions between ferricyanide and thiosulfate

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Science china chemistry 2005年第5期48卷 424-430页

作者： LI Di1, SUN Chunyan1, HUANG Yunjie1, LI Jinghong1,2.& CHEN Shaowei3 1. State Key Laboratory of Electroanalytical chemistry, changchun Institute of Applied chemistry, Chinese Academy of Sciences, changchun 13002., china 2. department of chemistry, Tsinghua University, Beijing 100084, china 3. department of chemistry, University of California, Santa Cruz, Santa Cruz, CA 95064, USA 1. State Key Laboratory of Electroanalytical chemistry changchun Institute of Applied chemistry Chinese Academy of Sciences 130022 Changchun China 2. department of chemistry Tsinghua University 100084 Beijing China 3. department of chemistry University of California 95064 Santa Cruz Santa Cruz CA USA

Electron transfer through the self-assembled monolayers (SAMs) on gold nanopar-ticles is investigated by using the monolayer protected gold nanoclusters (MPCs) as elec-tron-transfer mediators. 3-Mercaptopropionic acid (MPA) and 11-meraptoundecanoic acid (MUA) MPCs were employed to catalyze the redox reaction between potassium ferricyanide and sodium thiosulfate. The catalytic mechanism was proposed that the MPCs act as diffusing elec-tron-mediators and electron transfers to and from the MPCs surface. Therefore the electron transfer rate through the capping layers would be proportional to the MPCs catalyzed reaction rate, which was monitored by the UV absorbance of ferricyanide. The calculated apparent rate constant was orders of magnitude smaller than that of the maximum of tunneling current, which was attributed to the splited energy level of the nanoscale particles.

关键词： electron transfer, three-dimensional self-assembled monolayers, redox reaction, electron transfer mediator, surface effect.

Effect of solution concentration on the structured order and optical properties of short-chain polyene biomolecules

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Science china(Physics,Mechanics & Astronomy) 2010年第9期53卷 1646-1650页

作者： OUYANG ShunLi1,2.SUN ChengLin1,2.ZHOU Mi1,2.LI DongFei2.WANG WeiWei1,2.QU GuanNan1,LI ZuoWei1,2.GAO ShuQin1 & YANG JianGe3 1 State Key Laboratory of Superhard Materials,jilin University,changchun 130012.{2. 2.College of Physics,jilin University,changchun 13002.,{2. 3 The ordnance Engineering department,Air Force Aviation University,changchun 13002.,{2. 1. State Key Laboratory of Superhard Materials Jilin University Changchun 130012 China2. College of Physics Jilin University Changchun 130023 China3. The ordnance Engineering Department Air Force Aviation University Changchun 130022 China

We have measured the Raman spectra and UV-Vis absorption spectra of linear polyene biomolecules(β-carotene and lycopene) in CS2.at low concentrations(10-6-10-10 mol/L).With decreasing concentration,all the carbon-carbon vibrations form a coherent mode in ordered β-carotene and lycopene due to extended π-conjugation that gives strong electron-phonon coupling,which leads to an anomalous experimental *** observed an extremely high Raman scattering cross section(RSCS) and the Raman activities in β-carotene and lycopene are characterized by intensive overtones and ***,the UV-Vis absorption bands become narrower.

关键词： molecular structured order Raman spectroscopy Raman scattering cross section

Database of open-framework aluminophosphate syntheses:introduction and application(Ⅰ)

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Science china chemistry 2009年第11期52卷 1734-1738页

作者： YAN Yan1,LI JiYang1,QI Miao2.ZHANG Xiao1,YU JiHong1 & XU RuRen1 1 State Key Laboratory of Inorganic Synthesis and Preparative chemistry,jilin University,{2. 130012.china 2.department of chemistry,Northeast Normal University,{2. 130117,china 1. State Key Laboratory of Inorganic Synthesis and Preparative chemistry Jilin University Changchun 130012 China 2. department of chemistry Northeast Normal University Changchun 130117 China

The database of open-framework aluminophosphate(AlPO) syntheses has been established,which includes about 1600 synthetic *** analysis has been done on the basis of the framework composition,structure dimension,pore ring,and organic *** database will serve as useful guidance for the rational synthesis of microporous functional materials.

关键词： aluminophosphates open framework synthesis database

Robust observer-based control for uncertain discrete-time piecewise affine systems

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控制理论与应用（英文版） 2012年第2期10卷 236-243页

作者： Yahui GAO 1 , Zhiyuan LIU 2., Hong CHEN 3 1.AVIC (Aviation Industry Corporation of china) china Aviation Motor Control System Institute, Wuxi Jiangsu 2.4063, china 2.department of Control Science and Engineering, Harbin Institute of Technology, Harbin Heilongjiang 150001, china 3.department of Control Science and Engineering, jilin University, changchun jilin 13002., china AVIC (Aviation Industry Corporation of china) china Aviation Motor Control System Institute Wuxi Jiangsu China department of Control Science and Engineering Harbin Institute of Technology Harbin Heilongjiang China department of Control Science and Engineering Jilin University Changchun Jilin China

The main contribution of this paper is to present a novel robust observer-based controller design method for discrete-time piecewise affine systems with norm-bounded uncertainties. The key ideas are to construct a piecewise quadratic Lyapunov function to guarantee the stability of the closed-loop systems, approximate polytopic operating regions by ellipsoids, and use the singular value decomposition technique to treat the constraint of matrix equality. It is shown that the suggested control method can be formulated as linear matrix inequalities that are numerically feasible with commer- cially available software. A numerical example is also given to verify the proposed approach.

关键词： Piecewise affine systems Robust control Observer Linear matrix inequality

Comparison of photovoltaic devices based on MEH-PPV with various molecular weights

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Chinese Science Bulletin 2004年第21期49卷 2259-2261页

作者： KANG Bonan1,2. WANG Liduo1, YANG Yong1 & QIU Yong1 1. Key Laboratory of Organic Optoelectronics & Molecular Engineering of Ministry of Education, department of chemistry, Tsinghua Univer- sity, Beijing 100084,{2. 2. State Key Laboratory on Integrated optoelectronics, jilin University Region, changchun 13002.,{2. Key Laboratory of Organic Optoelectronics & Molecular Engineering of Ministry of Education Department of Chemistry Tsinghua University Beijing 100084 China

Polymer photovoltaic devices based on poly (2. methoxy-5-(2. -ethyl-hexyloxy)-1,4-phenylene vinylene) (MEH- PPV) with three weight-average molecular weights (Mw) have been fabricated with the device structure of ITO/PEDOT/ MEH-PPV/Ca/Ag, and the effect of the molecular weight on photovoltaic properties has been investigated. The experi- mental results show that the high molecular weight of MEH- PPV leads to low series resistance (Rs) and high short-circuit current. The low molecular weight of MEH-PPV leads to high shunt resistance (Rsh) and high open-circuit voltage. When the molecular weight is 6×105, the highest power con- version efficiency was observed.

关键词： MEHPPV 分子量光电器件载流子迁移率串联电阻并联电阻聚(2.甲氧基-5-(2.-乙基-乙氧基)-1,4-亚苯基乙烯撑)