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Synthesis,characterization,properties and crystal structure of heterometallic 1. coordination polymers {[CuLZn·CuLZn(H_2.)]·H_2.}_n

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Science China chemistry 2006年第4期49卷 338-344页

作者： TAO Ruojie1. LI Fu’an1. ZANG Shuangquan1. CHENG Yanxiang{3.& NIU Jingyang1.1. {1. and Chemical Engineering College of Henan University, Kaifeng 475001. China {3. Changchun {1. of {{3. {1., Chinese Academy of Sciences, Changchun 1.00{3., China 1. chemistry and Chemical Engineering College of Henan University Kaifeng 475001 China 2. Changchun {1. of {1. {2. Chinese Academy of Sciences Changchun 130022 China

Copper-zinc heterometallic 1. chain coordination polymer has been synthesized and characterized by elemental analysis, and IR spectra etc. The crystal structure was determined by single-crystal X-ray diffraction analyses. The title complex is 1. chain coordination polymer with the chemical formula {[CuLZn·CuLZn(H2.)]·H2.}n, where H4L=N-(2.hydroxybenzamido)-N’-(3.carboxy- lsalicylidene)ethylenediamine. Its structural unit is comprosed of two tetranuclear cycles formed by two dissymmetrical tetranuclear units. These units polymerized each other to form 1. chain coordi- nation polymer.

关键词： copper, zinc, heterometallic coordination polymer, crystal structure.

Synthesis and crystal structure of complex of Ce(NO_3._3.with N-(3.methyl-pyridin-2.yl)-formimidoyl-(3.methyl-pyridin-2.yl) hydrazone

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Science China chemistry 2004年第3期47卷 251-256页

作者： JIANG Yinzhi1.2.& HU Weixiao1.1. Department of Pharmaceutical Science, Zhejiang University of Technology, Hangzhou 3.0}03.1} China 2. Department of applied {1., Zhejiang {2. of Science and Technology, Hangzhou 3.0}03., China 1. Department of Pharmaceutical Science Zhejiang University of Technology 310032 Hangzhou China 2. Department of {1. {1. Zhejiang Institute of Science and Technology 310033 Hangzhou China

The reaction of 3.6-di-(3.methyl-pyridin-2.yI)-s-tetrazine (DMPTZ, II) with CeIII salt [Ce(NO3.3.· 6H2.] generates a new ligand, N-(3.methyl-pyridin-2.yl)-formimidoyl-(3.methyl-pyridin-2.yl) hydrazone (L), and forms a new complex: a mononuclear complex [Ce(L)(NO3.2.(H2.)3. · NO3.(III). Crystal data for III: space group P-1. with a = 0.71.3.4) nm, b = 1.1.3.(2. nm, c = 1.4572.3. nm, α= 1.2.1.(2.°, β= 99.81.3.°, γ= 91.1.(3.°, Z = 2. V = 1.1..6(7) nm3. μ = 2.1.0} mm?1.and F(000) = 63.. L acts as a tri-dentate chelating ligand in III. There are 1. coordination sites around Ce3. of III, which are respectively occupied by seven oxygen atoms (four from two nitrate anions and three from three H2. molecules) and three nitrogen atoms (all from L). The cerium atom and three chelating nitrogen atoms are coplanar. The mechanism of the metal assisted decomposition is discussed briefly.

关键词： rare earth, complex, crystal structure, synthesize, 3.6-bis (3.methyl-pyridin-2.yl)-s-tetrazine, N-(3.methyl-pyridin- 2.yl)-formimidoyl-(3.methyl-pyridin-2.yl) hydrazone.

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 {1., Changchun {1. of {2. {1., Chinese Academy of Sciences, Changchun 1.002., China 2. Department of {1., Tsinghua University, Beijing 1.0084, China 3. Department of {1., University of California, Santa Cruz, Santa Cruz, CA 95064, USA 1. State Key Laboratory of Electroanalytical chemistry Changchun {1. of {{3. chemistry Chinese Academy of Sciences 130022 Changchun China 2. Department of {1. 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 1.-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.

Three-dimensional configurations of organic/inorganic hybrid nanostructural blocks (I).A quantum mechanical investigation for ladder-like structure of vinylsilsesquioxane

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Science China chemistry 2004年第5期47卷 388-395页

作者： ZHANG Xingwen1.2. HU Lijiang1. HUANG Yudong1. SUN Dezhi2.& SUN Yi3.1. Department of applied {1.,Harbin {2. of Technology, HUANG Yudong, Harbin 1.0001. China 2. Department of Environmental Engineering, Harbin {2. of Technology, Harbin 1.0001. China 3. Department of Experimental Mechanics,Harbin {2. of Technology, Harbin 1.0001. China 1. Department of applied {1. Harbin Institute of Technology HUANG Yudong 150001 Harbin China 2. Department of Environmental Engineering Harbin Institute of Technology 150001 Harbin China 3. Department of Experimental Mechanics Harbin Institute of Technology 150001 Harbin China

The organic/inorganic hybrid nanostructural vinylsilsesquioxanes (VSSO) were prepared from the hydrolytic condensation of vinyltrimethoxysilane (VMS). The proposed formu- las of VSSO were assigned with standard spectroscopic techniques, FTIR, NMR (1., C and 1. 2.Si) and MALDI-TOF MS, and a generic formula of the SSO, Tn(OH)x(OR’)y(x, y = 0, 1. 2.; n = 1. 2.; T = RSiO1.5 ?(x+y)/2.). Geometric parameters (Si-O and Si-C bond lengths, Si-O-Si and O-Si-O bond angles) and total energies of the multi-structures of VSSO were calculated by a quantum mechanical investigation and molecular symmetries. According to the results of the calculation, most molecules had stabler ladder structures than the cage isomers, therefore, the most probably reasonable and optimum structure of the VSSO system was the ladder type.

关键词： vinyltrimethoxysilane (VMS), silsesquioxanes (SSO), sol-gel process, quantum mechanical calculation, MNDO.

A trust region algorithm for bilevel programing problems

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Chinese Science Bulletin 1998年第10期43卷 820-824页

作者： LIU Guoshan 1. HAN Jiye 2.and WANG Shouyang 3.1. Department of Mathematics, Beijing Normal University, Beijing 1.0875, China 2. institute of {1. Mathematics, Chinese Academy of Sciences, Beijing 1.0080, China 3. institute of Systems Science, Chi Department of Mathematics Beijing Normal University Beijing China institute of {1. Mathematics Chinese Academy of Sciences Beijing China institute of Systems Science Chinese Academy of Sciences Beijing China

A trust region algorithm is proposed for solving bilevel programming problems where the lower level programming problem is a strongly convex programming problem with linear constraints. This algorithm is based on a tr... 详细信息

关键词： bilevel programming problem trust region algorithm global convergence.

A new DNA algorithm to solve graph coloring problem

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Progress in Natural Science:Materials International 2007年第6期17卷 733-738页

作者： Jiang Xingpeng1. Li Yin2. Meng Ya3.and Meng Dazhi2.1. National Laboratory of Pattern Recognition,institute of Automation, Chinese Academy of Sciences, Beijing 1.0080, China 2. College of {1. Sciences, Beijing University of Technology, Beijing 1.002., China 3. School of Science, Beijing institute of Technology, Beijing 1.0081. China) National Laboratory of Pattern Recognition Institute of Automation Chinese Academy of Sciences Beijing 100080 China College of applied Sciences Beijing University of Technology Beijing 100022 China School of Science Beijing Institute of Technology Beijing 100081 China

Using a small quantity of DNA molecules and little experimental time to solve complex problems successfully is a goal of DNA computing. Some NP-hard problems have been solved by DNA computing with lower time complexity than conventional computing. However, this advantage often brings higher space complexity and needs a large number of DNA encoding molecules. One example is graph coloring problem. Current DNA algorithms need exponentially increasing DNA encoding strands with the growing of problem size. Here we propose a new DNA algorithm of graph coloring problem based on the proof of four-color theorem. This algorithm has good properties of needing a relatively small number of operations in polynomial time and needing a small number of DNA encoding molecules (we need only 6R DNA encoding molecules if the number of regions in a graph is R).

关键词： DNA computing NP-hard problem graph coloring problem.

Existence of the solutions and the attractors for the large-scale atmospheric equations

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Science China Earth Sciences 2006年第6期49卷 650-660页

作者： HUANG Haiyang1.& GUO Boling2.1. Department of Mathematics, Beijing Normal University, Beijing 1.0875, China 2. institute of {1. Physics and Computational Mathematics, Beijing 1.0080, China 1. Department of Mathematics Beijing Normal University Beijing 100875 China 2. {1. of {1. Physics and Computational Mathematics Beijing 100080 China

In this paper, firstly, the proper function space is chosen, and the proper expression of the operators is introduced such that the complex large-scale atmospheric motion equations can be described by a simple and abstract equation, by which the definition of the weak solution of the atmospheric equations is made. Secondly, the existence of the weak solution for the atmospheric equations and the steady state equations is proved by using the Galerkin method. The existence of the non-empty global attractors for the atmospheric equations in the sense of the Chepyzhov-Vishik’s definition is obtained by constructing a trajectory attractor set of the atmospheric motion equations. The result obtained here is the foundation for studying the topological structure and the dynamical behavior of the atmosphere attractors. Moreover, the methods used here are also valid for studying the other atmospheric motion models.

关键词： atmosphere equations, weak solution, trajectory attractor, global attractor, equilibrium.

Potential energy surfaces for low-lying electronic states of SO_2

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Science China chemistry 2006年第4期49卷 289-295页

作者： LI Anyang1. SUO Bing2. WEN Zhenyi2.& WANG Yubin2.1. Shanxi Key Laboratory of Physico-inorganic chemistry, Department of chemistry, Northwest University, Xi’an 71.069, China 2. {2. of Modern Physics, Northwest University, Xi’an 71.069, China 1. Shanxi Key Laboratory of Physico-inorganic chemistry Department of Chemistry Northwest University Xi’an 710069 China 2. {1. of Modern Physics Northwest University Xi’an 710069 China

The potential energy surfaces for the nine low-lying electronic states of SO2.have been constructed by using the multi-reference second order perturbation theory (MRPT2. with the basis set cc-pVTZ. The optimized geometries and the adiabatic excitation energies of these states are in good agreement with experiments and previous calculations. The crossings and avoided crossings dis- played in the potential energy surfaces are expounded.

关键词： cross of PES, MRPT2. SO2 (sulfur dioxide).

Global convergence property of s-dependent GFR conjugate gradient method

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Chinese Science Bulletin 1998年第23期43卷 1959-1965页

作者： WANG Changyu 1.2.and ZHANG Yuzhong\+1.1. {1. of Operations Research in Qufu Normal University, Qufu 2.3.0}5, China 2. {1. of {2. Mathematics, Chinese Academy of Sciences, Beijing 1.0080, China institute of Operations Research Qufu Normal University Qufu China institute of {1. Mathematics Chinese Academy of Sciences Beijing China

An \%S\%_dependent GFR method and a generalized conjugate gradient method are designed. Two estimated values of upper bounds for the ratio of β k to β FR k are given. The two convergence theorems are proved. The global convergent properties of \%s\%_dependent GFR method are obtained adopting several choice strategies of steplength and some results in recent literature are extended.

关键词： steplength linear search global convergence conjugate gradient.