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Assembly of gold nanoparticles with H_(1.)TTPR (3a, 4, 5, 8, 9, 9a, 1., 1.-octa-hydro-2H,3H-1.6,7,1.-tetrathia-perylene) as the rigid cross-linker

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Chinese Science Bulletin 2004年第8期49卷 789-792页

作者： SHAO Xiangfeng1.2, WANG Tongxin1. ZHANG Deqing1. XU Wei 1.& ZHU Daoben1.1. Organic Solids Laboratory, Center for Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 1.0080, China 2. Graduate School, Chinese Academy of Sciences, Beijing 1.0080, China Correspondence should be addressed to Zhu Daoben or Zhang Deqing (e-mail: dqzhang@***) Organic Solids Laboratory Center for Molecular Sciences Institute of Chemistry Chinese Academy of Sciences Beijing 100080 China Graduate School Chinese Academy of Sciences Beijing 100080 China

Gold nanoparticles were assembled with the rigid cross-linker, H1.TTPR. The assembly process was stud-ied with the UV-vis spectroscopy and TeM. By adjusting the amount of H1.TTPR added to the gold nanoparticle solutio... 详细信息

关键词：纳米金粒子集成刚性交叉连接 TeM UV-力光谱学

Structures and stability of isomers of[Si,N,N,P]system

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Science China Chemistry 2004年第2期47卷 98-105页

作者： KAN Wei1. YU Haitao1. LI Mingxia1. FU Honggang1.2 & SUN Jiazhong1.2 1. College of Chemistry and Chemical engineering, Heilongjiang University, Harbin 1.0080, China 2. State Key Laboratory of Theoretical and Computational Chemistry, Institute of Theoretical Chemistry, Jilin University, Changchun 1.0023, China 1. College of Chemistry and Chemical engineering Heilongjiang University 150080 Harbin China 2. State Key Laboratory of Theoretical and Computational Chemistry Institute of Theoretical Chemistry Jilin University 130023 Changchun China

Some stationary points on the potential energy surface of [Si, N, N, P] system were located at the B3LYP/6-31.G(d) and QCISD(t)/6-31.+G(2df)(single-point) levels of theory, while the isomerization, structures, and stability of these obtained isomers were suggested. The computed results indicate that only four-membered ring isomer SiNPN(e1. 2A'), which possesses butterfly-like structure and Si-P cross bonding, is kinetically stable in all optimized isomers. Other isomers may be considered as kinetically unstable towards isomerization or dissociation because of the corresponding smaller reaction barriers. Furthermore, the present paper also proposes electronic and geometric structures, vibrational frequencies and the corresponding vibrational modes, dipole moments, and rotational constants of isomer e1. To make use of the computed results, we can clearly know that the reaction pathway via an intermediate e3 (SiNPN) is the most favorable channel producing isomer e1.from fragments SiN(2Π) and PN (1.), which have been well characterized in space, and thus, isomer e1.can be considered as a candidate for interstellar observation. The reaction enthalpy of SiN(2Π) + PN(1.)→ e1.and the standard enthalpy of formation of isomer e1.are 21..25 and 457.99 kJ/mol, respectively, at 298.1. K. Keywords potential energy surface - [Si,N,N,P] system - isomerization - kinetic stability

关键词： potential energy surface, [Si,N,N,P] system, isomerization, kinetic stability.

Investigation of solvatochromism and aggregation behavior of C_(60)(C_4H_(1.)N^+)I^- in binary solvent mixtures

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Chinese Science Bulletin 2003年第18期48卷 1938-1942页

作者： WANG Guanwu1. HAO erhong1. JIAO Lijuan1.& YAN Lifeng2 1. Department of Chemistry, University of Science and Technology ofChina, Hefei 230026, China 2. Department of Chemical Physics, University of Science and Technol-ogy of China, Hefei 230026, China Correspondence should be addressed to Wang Guanwu (e-mail: gwang @***) Department of Chemistry University of Science and Technology of China Helei 230026 China

Water-soluble N,N-dimethyl[60]fulleropyrro-lidinium iodide (C60(C4H1.N+)I-), when dissolved in binarymixtures of tetrahydrofuran and water, was found to exhibit remarkable solvatochromism. Correspondingly, the UV-vis spectra showed obvious changes by variation of the solventcomposition of tetrahydrofuran and water. It was found that both concentration and temperature had strong influence on the stability of monomer-state C60(C4H1.N+)I-, while theyhad little effect on the stability of aggregated C60(C4H1.N+) I-The formation of cluster was confirmed by TeM and AFMmeasurements.

关键词： N N-dimethylfulleropyrrolidinium iodide solvato-chromism aggregation.

Formation and evolution of Ancient Lakes on South Coast Plain of Laizhou Bay

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Chinese Journal of Population,Resources and environment 2005年第4期3卷 26-32页

作者： Han Mei 1. Zhou Baohua 2, Yang Peilin 1.Gao Guiqin 1.& Zhang Weiying 1.1. Department of Geography, Shandong Normal University, Jinan 25001., China 2. Department of Geography, Jinan University, Jinan 250001. China Department of Geography Shandong Normal University Jinan 250014 China Department of Geography Jlnan University Jinan 250001 China

Based on the data of historical geography, the analysis of the stratigraphic section, and the textual research of place names and satellite photographic interpretations, the authors study the formation and evolution of ancient lakes on the south coast plain of Laizhou Bay where there were once three lakes: Judian Lake, Qingshuibo Lake and Biehua Lake. All the lakes formed 6000 years ago evolved from the lagoons near the estuary and went through two periods, the golden age in the Middle Holocene and the shrinking age in the Late Holocene. The disappearance of the lakes resulted from the drying climate, the migration of the river courses and the activities of human beings. Among the three reasons, the migration of the river courses is the main one.

关键词： ancient lake cause historical evolution south coast plain of Laizhou Bay

evaluation Method of Web Site Structure Based on Web Structure Mining

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Wuhan University Journal of Natural Sciences 2003年第3A期8卷 791-796页

作者： Li Jun\|e 1., Zhou Dong\|ru 2 1. Computer Center,Wuhan University, Wuhan 430072, Hubei, China 2. School of Computer,Wuhan University, Wuhan 430072, Hubei,China Wuhan University Computer Center Wuhan Hubei China (GRID:grid.49470.3e) (ISNI:***) Wuhan University School of Computer Wuhan Hubei China (GRID:grid.49470.3e) (ISNI:***)

The structure of Web site became more complex than before. During the design period of a Web site, the lack of model and method results in improper Web structure, which depend on the designer's experience. From the point of view of software engineering, every period in the software life must be evaluated before starting the next period's work. It is very important and essential to search relevant methods for evaluating Web structure before the site is completed. In this work, after studying the related work about the Web structure mining and analyzing the major structure mining methods (Page\|rank and Hub/Authority), a method based on the Page\|rank for Web structure evaluation in design stage is proposed. A Web structure modeling language WSML is designed, and the implement strategies for evaluating system of the Web site structure are given out. Web structure mining has being used mainly in search engines before. It is the first time to employ the Web structure mining technology to evaluate a Web structure in the design period of a Web site. It contributes to the formalization of the design documents for Web site and the improving of software engineering for large scale Web site, and the evaluating system is a practical tool for Web site construction.

关键词： web structure mining page\|rank web structure evaluation modeling language for web structure

epigenetic reprogramming in mammalian nuclear transfer

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Chinese Science Bulletin 2004年第8期49卷 766-771页

作者： LI Shijie1.2, DU Weihua1.& LI Ning1.1. State Key Laboratory for Agrobiotechnology, China Agricultural University, Beijing 1.0094, China 2. Department of Biochemistry and Molecular Biology, College of Life Science, Hebei Agriculture University, Baoding 071.01. China Correspondence should be addressed to Li Ning (e-mail: ninglbau@ ***) State Key Laboratory for Agrobiotechnology China Agricultural University Beijing 100094 China Department of Biochemistry and Molecular Biology College of Life Science Hebei Agriculture University Baoding 071001 China

Somatic cloning has been succeeded in some species, but the cloning efficiency is very low, which limits the application of the technique in many areas of research and biotechnology. The cloning of mammals by somatic cell nuclear transfer (NT) requires epigenetic reprogramming of the differentiated state of donor cell to a totipotent, embry-onic ground state. Accumulating evidence indicates that in-complete or inappropriate epigenetic reprogramming of do-nor nuclei is likely to be the primary cause of failures in nu-clear transfer. This review summarizes the roles of various epigenetic mechanisms, including DNA methylation, histone acetylation, imprinting, X-chromosome inactivation, te-lomere maintenance and expressions of development-related genes on somatic nuclear transfer.

关键词：哺乳动物细胞核液迁移后成程序改编 DNA甲基化作用组蛋白乙酰化作用 X-染色体活化端粒印痕基因表达克隆

A TRUST-ReGION ALGORITHM FOR SOLVING MINI-MAX PROBLeM

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Journal of Computational Mathematics 2018年第6期36卷 776-791页

作者： Bothina e1.Sobky Abdallah Abotahoun Department of Mathematics Alexandria University Alexandria Egypt

In this paper, we propose an algorithm for solving inequality constrained mini-max optimization problem. In this algorithm, an active set strategy is used together with mul- tiplier method to convert the inequality constrained mini-max optimization problem into unconstrained optimization problem. A trust-region method is a well-accepted technique in constrained optimization to assure global convergence and is more robust when they deal with rounding errors. One of the advantages of trust-region method is that it does not require the objective function of the model to be convex. A global convergence analysis for the proposed algorithm is presented under some conditions. To show the efficiency of the algorithm numerical results for a number of test problems are reported.

关键词： Mini-max problem Active-set Multiplier method Trust-region Global con-vergence

electronic structure and magnetic properties of SmCo7-xTix

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Science China(Physics,Mechanics & Astronomy) 2006年第1期49卷 38-45页

作者： ZHANG Changwen1. LI Hua1. DONG Jianmin1. GUO Yongquan2 & LI Wei2 1. School of Physics and Microelectronics, Shandong University, Jinan 2501.0, China 2. Institute of Functional Materials, Central Iron and Steel Research Institute, Beijing 1.0081. China 1. School of Physics and Microelectronics Shandong University Jinan 250100 China 2. Institute of Functional Materials Central Iron and Steel Research Institute Beijing 100081 China

electronic structure of SmCo7-xTix alloy has been studied by means of the spin-polarized MS-Xα method. It is shown that a few of electrons are transferred to Sm(5d) orbital due to orbital hybridization between Sm and Co atoms. The exchange interaction between 5d-3d electrons is stronger, which is the main reason resulting in the long-range ferromagnetic order between Co and Sm atoms. The Curie temperature of SmCo7-xTix is generally lower than that of pure Co metal, which may be explained by the weaker aver- age of coupling strength between Co sites due to some negative exchange couplings occurring mainly at 2e site. The calculated results for the Sm5Co28Ti6 cluster may lead to a better understanding of why SmCo7-xTix is stable phase. Since the negative interaction of 2e sites weakens and the bonding at eF strengthens with increasing Ti concentration, which result in the decrease in the free energy of the alloy, the stable ferromagnetic order forms inside SmCo7-xTix. Considering the localization of 4f states and 5d moment arising from the orbital hybridization, the calculated moment is 9.47μB per formula unit that is in agreement with experiments.

关键词： electronic structure, spin polarization, atomic magnetic moment, exchange coupling, Curie temperature.

Modeling the fate of paddy field pesticide in surface water and environmental risk assessment

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Journal of environmental Sciences 2000年第3期12卷 337-343页

作者： LI Shi\|yu 1. Tohru Morioka 2 (1. Institute of environmental Science, Zhongshan University, Guangzhou 51.275, China. e-mail: eeslsy@*** 2.Department of environmental engineering, Osaka University, Yamada oka 2 1. Suita, Osaka 565, Japan. e- 中山大学广东广州 51 0 2 75 Osaka University 日本 Osaka 56 5

The risk of drinking water is greatly concerned because of the large amount of pesticide applied to paddy field and the contamination of drinking water sources due to the runoff. A mathematical model is developed, based on the mass balance, to predict the fate of paddy field pesticides from application, runoff and mixing in a river, taking account of the physical chemical properties and processes of volatilization, degradation, adsorption and desorption. The model is applied to a river basin in Japan to estimate the contaminant level of several popularly used pesticides at the water intakes. The health risk in drinking water induced by each pesticide concerned is estimated and evaluated by comparing with the acceptable daily intake values(ADI) and with that induced by trihalomethanes. An index to evaluate the total risk of all pesticides appearing in water is proposed. The methods for risk management are also discussed.

关键词： modeling pesticide paddy field environmental risk assessment drinking water