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ON BOUNDARY TREATMENT FOR THE NUMERICAL SOLUTION OF THE INCOMPRESSIBLE NAVIER-STOKES EQUATIONS WITH FINITE DIFFERENCE METHODS

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Journal of Computational Mathematics 1996年第2期14卷 135-142页

作者： Huang, LC chinese acad sci LSECINST COMPUTAT MATH & SCI ENGN COMPBEIJINGPEOPLES R CHINA

Structure,Fluorescence and Stability of CdS Nanoparticles Prepared in Air

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Journal of Materials science & Technology 1998年第5期14卷 389-394页

作者： Chen, Wei Lin, Zhaojun Wang, Zhangguo Xu, Yan Lin, Lanying chinese acad sci Inst Semicond Lab Semicond Mat Sci Beijing 100083 Peoples R China

CdS nanoparticles were prepared in air and their stability by air annealing was studied. A small change in crystal structure and particle size was observed by air annealing, but a rapid reduction in fluorescence was found. Through investigation, it was revealed that it is the surface change or reconstruction rather than the variation of the size or structure that decreases the fluorescence. The emission of the particles consists with two peaks which are dependent on the excitation energy. The two peaks were considered to be arisen from two different sizes of nanoparticles and may be explained in terms of selectively excited photoluminescence. Finally, the problem of why the discrete state of nanoparticles are able to be resolved in the photoluminescence excitation spectrum but could not be differentiated in the absorption spectrum was discussed. (Edited author abstract) 27 Refs.

关键词： Cadmium compounds

ON THE VERTEX PARTITION EQUATION OF ROOTED LOOPLESS PLANAR MAPS

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Acta Mathematica scientia 1990年第2期10卷 167-172页

作者：刘彦佩 chinese acad sci INST APPL MATHBEIJINGPEOPLES R CHINA chinese acad sci INST MATHBEIJINGPEOPLES R CHINA

This paper provides a functional equation astisfied by the generating function for enumerating rooted loopless planar maps with vertex partition. A kind of applications in enumerating, by providing explicit formulae, a type of rooted loopless planar maps with the maximum valency of vertices given are described. Meanwhile, the functional equation for enumerating rooted loopless planar maps (connected) with the edge number and the valency of root-vertex as the parameters is also derived directly.

关键词： ON THE VERTEX PARTITION EQUATION OF ROOTED LOOPLESS PLANAR MAPS

Analysis and design for the second order nonlinear continuous extended states observer

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chinese science Bulletin 2000年第21期45卷 1938-1944页

作者： Yi Huang Jingqing Han chinese acad sci Acad Math & Syst Sci Inst Syst Sci Beijing 100080 Peoples R China

The extended state observer (ESO) is a novel observer for a class of uncertain systems. Since ESO adopts the continuous non-smooth structure, the classical observer design theory is hard to use for ESO analysis. In this note, the self-stable region (SSR) approach, which is a nonlinear synthesis method for nonlinear uncertain systems, will be used for ESO design and its stability analysis. The advantages of the non-smooth structure in ESO for improving the convergence properties and the estimation precision will be shown.

关键词： extended state observer (ESO) continuous non-smooth structure self-stable region (SSR) method.

TRIMETHYLSILYLATED SILICA AS RHEOLOGY MODIFIER FOR SILICONE RESINS

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chinese Journal of Polymer science 2000年第1期18卷 51-55页

作者： Wei Huang Ying Huang Yunzhao Yu Center for Molecular science, Institute of Chemistry, chinese academy of sciences, Beijing 100080, China chinese acad sci Inst Chem Ctr Mol Sci Beijing 100080 Peoples R China

Trimethylsilylated silica was synthesized. through hydrolytic condensation of tetraethoxysilane followed by trimethylsilylation. Rheological properties of the silicone resin with trimethylsilylated silica as modifier were studied. It turned out that the particle size of silica was important to the rheological behavior of the modified resin. Trimethylsilylated silica of medium particle size shows the strongest tendency of forming physical network in the resin.

关键词： silica trimethylsilylation rheology modifier silicone resins

Effects of diatoms on reproduction and growth of marine copepods

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Progress in Natural science:Materials International 2004年第10期14卷 1-7页

作者： ZHANG Guangtao 1,2 and SUN Song 1 (1.Key Laboratory of Marine Ecology&Environment sciences,Institute of Oceanology,chinese academy of sciences,Qingdao266071,China 2.Graduate School,chinese academy of sciences,Beijing100039,China) chinese acad sci Inst Oceanol Key Lab Marine Ecol & Environm Sci Qingdao 266071 Peoples R China chinese acad sci Grad Sch Beijing 100039 Peoples R China

Two hot spots in marine ecology,deleterious effects of diatoms and feeding selectivity of copepods,as well as new progress on these two issues achieved in the recent ten years,are *** two issues are considered correlated *** and their metabolites can induce deleterious effects on growth,reproduction and development of copepods,including increase of mortality and decrease of egg production,hatching and growth *** negative effects,resulting from either chemical toxin or nutritional defi-ciency,can be conquered in natural environments by diverse *** is therefore concluded that deleterious effects of diatoms observed in laboratory or during blooming period are only a special case that accommodation of feeding strategy of copepods is *** under-stand their feeding strategy in natural environments is a prerequisite to explaining the mechanisms of deleterious effects caused by diatoms,and makes it possible to re-evaluate the energy flow in marine ecosystems.

关键词： diatoms copepod feeding strategy reproduction deleterious effects

SYNTHESIS AND CHARACTERIZATION OF SILAZANE OLIGOMER CONTAINING 1,1,3,3,5,5-HEXAMETHYLCYCLOTRISILAZANE

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chinese Journal of Polymer science 2000年第5期18卷 449-452页

作者： Cai-hong Xu Ning Zhou Ze-min Xie Center for Molecular science, Institute of Chemistry, chinese academy of sciences, Beijing 100080, China chinese acad sci Inst Chem Ctr Mol Sci Beijing 100080 Peoples R China

A new silazane oligomer containing cyclotrisilazane was synthesized by KH-catalyzed dehydro-coupling reactions between diphenylsilane and 1,1,3,3,5,5-hexamethylcyclotrisilazane (D-3(N)).

关键词： silazane oligomer diphenylsilane cyclotrisilazane dehydro-coupling reaction

A NOVEL TITANIUM COMPLEX WITH LINKED β-DIKETONATO-INDENYL LIGAND FOR CATALYTIC SYNDIOSPECIFIC POLYMERIZATION OF STYRENE

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chinese Journal of Polymer science 2002年第3期20卷 213-217页

作者： Jun Wang De-min Xu Zhong-yang Liu Yong-jun Chen Dong Wang Center for Molecular science, Institute of Chemistry chinese academy of sciences, Beijing 100080, China chinese acad sci Inst Chem Ctr Mol Sci Beijing 100080 Peoples R China

A novel ligand (3), in which the indenyl group is linked to a β-diketone moiety through a three-carbon bridge, andits titanium complex (4) were synthesized. The titanium complex was employed as a metallocene analog with co-catalystmethylaluminoxane (MAO) in catalytic syndiospecific polymerization of styrene to give highly syndiotactic polystyrene(s-PS, 96%-97%). Polymerization temperature (T_p) strongly influenced the catalytic activity and syndiotacticity of theproduced PS. The activities of catalyst 4 increase from 1.84×10~6 to 3.26×10~6 gPS/molTi·h with the increase of T_p from60℃ to 80℃ and the syndiotacticities of the produced s-PS also increase slightly. Then, both the catalytic activity and thesyndiotacticity of PS decrease at T_p of 90℃.

关键词： β-Diketone Metallocene Syndiospecific polymerization Polystyrene

A NOTE ON THE NONLINEAR CONJUGATE GRADIENT METHOD

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Journal of Computational Mathematics 2002年第6期20卷 575-582页

作者： Dai, Yu-hong Yuan, Ya-xiang chinese acad sci Acad Math & Syst Sci Inst Computat Math & Sci Engn Comput State Key Lab Sci & Engn Comput Beijing 100080 Peoples R China

Discusses several aspects of the linear conjugate gradient method for unconstrained optimization problems. General condition concerning the scalar; Convergence of the famous Fletcher-Reeves and Polak-Ribiere-Polyak co... 详细信息

关键词： unconstrained optimization conjugate gradient line search global convergence