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Local electronic structure and magnetic properties of 3. transition metal doped GaAs

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Science China(Physics,Mechanics & Astronomy) 2008年第5期51卷 470-480页

作者： LIN He1 & DUAN HaiMing2. Department of chemistry,institute of {2. chemistry,xinjiang University,urumqi 83.046,China 2.epartment of Physics,xinjiang University,urumqi 83.046,China 1. Department of chemistry Institute of Applied Chemistry Xinjiang University Urumqi 830046 China 2. Department of Physics Xinjiang University Urumqi 830046 China

The local electronic structure and magnetic properties of GaAs doped with 3. transition metal (Sc, Ti, V, Cr, Mn, Fe, Co, Ni) were studied by using discrete variational method (DVM) based on density functional theory. The calculated result indicated that the magnetic moment of transition metal increases first and then decreases, and reaches the maximum value when Mn is doped into GaAs. In the case of Mn concentration of 1.4%, the magnetic moment of Mn is in good agreement with the experimental result. The coupling between impure atoms in the system with two impure atoms was found to have obvious variation. For different transition metal, the coupling between the impure atom and the nearest neighbor As also has different variation.

关键词： diluted magnetic semiconductor density functional theory 3. transition metal cluster model electronic structure

FeS_(2. (pyrite) electrodeposition thin films and study of growth mechanism

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Science China(Technological Sciences) 2005年第6期48卷 601-611页

作者： DONG Youzhong1, ZHENG Yufeng1, ZHANG Xiaogang2. DUAN He1, SUN Yanfei1 & CHEN Yanhua1 1. Department of Physics, xinjiang University, urumqi 83.046, China {2., xinjiang University, urumqi 83.046, China 1. Department of Physics Xinjiang University 830046 Urumqi China 2. institute of applied chemistry Xinjiang University 830046 Urumqi China

Ferrous sulfide (FeS) thin films were initially electrodeposited on indium-tin oxide (ITO) substrates in the aqueous solution containing iron, sulfur elements and then annealed in the sulfur atmosphere. Thereby, we successfully obtained the single-phased iron pyrite (FeS2. thin films with good quality. The experimental parameters for electrodeposition and the post-growth thermal-dynamical conditions have been calculated so that more details about the effect of thermal-dynamical conditions on the micromechanism concerned with the iron pyrite crystal growth as well as the properties of the samples have been discussed.

关键词： electrodeposition, FeS2 (pyrite), thin films, growth dynamics.

On the periodic solutions of a type of differential-iterative equations

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Chinese Science Bulletin 1998年第3期43卷 204-206页

作者： GE Weigao 1, LIU Zhengrong 2.and YU Yuanhong 3.1. Department of applied Mathematics, Beijing institute of Technology, Beijing 100081, China 2. Department of Mathematics, Yunnan University, Kunming 650091, China 3. institute of applied Mathematics, C Department of applied Mathematics Beijing Institute of Technology Beijing China Department of Mathematics Yunnan University Kunming China institute of applied Mathematics Chinese Academy of Sciences Beijing China

Sufficient conditions for the existence of periodic solutions to a type of nonautonomous differential_iterative equations are given.

关键词： differential_iterative equation periodic solution fixed point.

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 {2. chemistry, Chinese Academy of Sciences, Changchun 13.02., 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 {2. 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.

Synthesis,characterization,properties and crystal structure of heterometallic 1D 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 Yanxiang2.& NIU Jingyang1 1. chemistry and Chemical Engineering College of Henan University, Kaifeng 475001, China 2. Changchun {3. of {2. chemistry, Chinese Academy of Sciences, Changchun 13.02., China 1. chemistry and Chemical Engineering College of Henan University Kaifeng 475001 China 2. Changchun institute of applied {2. Chinese Academy of Sciences Changchun 130022 China

Copper-zinc heterometallic 1D 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 1D 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 1D chain coordi- nation polymer.

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

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 {3.,Harbin {2. of Technology, HUANG Yudong, Harbin 150001, China 2. Department of Environmental Engineering, Harbin {2. of Technology, Harbin 150001, China 3. Department of Experimental Mechanics,Harbin {2. of Technology, Harbin 150001, China 1. Department of applied chemistry 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 (1H, C and 13.2.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 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 100080, China 2. College of applied Sciences, Beijing University of Technology, Beijing 10002., China 3. School of Science, Beijing institute of Technology, Beijing 100081, 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.

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 100875, China 2. institute of {3. Mathematics, Chinese Academy of Sciences, Beijing 100080, China 3. institute of Systems Science, Chi Department of Mathematics Beijing Normal University Beijing China institute of applied 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.

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 3.003.0} China 2. Department of {3. chemistry, Zhejiang {2. of Science and Technology, Hangzhou 3.003., China 1. Department of Pharmaceutical Science Zhejiang University of Technology 310032 Hangzhou China 2. Department of applied chemistry 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 = 0.713.(4) nm, b = 1.113.(2. nm, c = 1.4572.3. nm, α= 102.13.2.°, β= 99.81(3.°, γ= 91.10(3.°, Z = 2. V = 1113.6(7) nm3. μ = 2.12. mm?1 and F(000) = 63.. L acts as a tri-dentate chelating ligand in III. There are 10 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.