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Science Bulletin 2005年第18期 33-38页

作者： ZHANG Guiqin1,2. HUANG Jiangen1,3, HUANG Yuanhe1, FANG Decai1 & ZHANG Deqing4 1. Department of Chemistry, beijing Normal university, beijing 100875, china 2. Department of Physics, Qujing Normal College, Qujing 655000, china 3. Department of Chemistry, Jinggangshan College, Ji’an 343009, china 4. Organic Solids Laboratory, center for molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, beijing 100080, china

The mechanism of antiferromagnetic coupling in an Ag (I) complex of nitronyl nitroxide is investigated by means of the broken-symmetry approach within the density functional method (DFT-BS). The magneto-structural corre-lation and the single-occupied molecular orbital (SOMO) analysis reveal the existence of the antiferromagnetic cou-pling pathway along nitronyl nitroxide units via Ag (I) ion, and that the Ag (I) ion plays an important bridge role. The spin population analysis also shows the existence of spin de-localization along the ONCNO-Ag-ONCNO chain. It is found that the non-typical covalent bonds with major ionic charac-ter between Ag (I) ions and oxygen atoms of nitronyl nitrox-ide units can be used to mediate the spin-spin interaction of nitronyl nitroxides.

关键词： nitronyl nitroxide Ag (I) complex antiferromagnetic coupling density function theory molecular orbital method.

hhlim基因表达产物的亚细胞定位及其在细胞肥大中的意义

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生物化学与生物物理进展 2003年第1期30卷 67-71页

作者：郑斌温进坤韩梅周爱儒河北医科大学基础医学研究所北京大学医学部生物化学与分子生物学系北京100083

hhlim是从胎儿心脏中新近分离和克隆得到的与心脏发生相关的基因 ,其表达产物作为转录因子参与多种基因的转录调控和细胞的发育与分化过程 .用细胞转染方法将外源性hhlim基因导入处于分化过程中的小鼠成肌细胞C2.12.,发现该基因强制性... 详细信息

hhlim是从胎儿心脏中新近分离和克隆得到的与心脏发生相关的基因 ,其表达产物作为转录因子参与多种基因的转录调控和细胞的发育与分化过程 .用细胞转染方法将外源性hhlim基因导入处于分化过程中的小鼠成肌细胞C2.12.,发现该基因强制性表达可使C2.12.胞体积明显增大 .RT PCR和蛋白质印迹结果表明 ,hhlim促细胞肥大与诱导α 肌动蛋白 (α actin)过表达及重新启动胚胎基因BNP表达有关 .用绿色荧光蛋白 hhlim融合蛋白表达载体转染处于分化过程的C2.12.胞 ,发现转染不同时间 ,表达产物的亚细胞定位发生动态变化 ,表现为先在胞核和胞质中均有分布 ,而后定位于胞质的变化规律 .应用免疫共沉淀证实 ,hhlim在胞质中以与α actin相互缔合的方式存在 .

关键词： hhlim基因表达产物亚细胞定位细胞肥大 α-肌动蛋白脑钠肪心肌肥厚

Hydrogenation and Anisotropic Expansions in R_3Fe_(2.-x)T_x (R=Y, Ce, Nd, Sm, Gd, Tb and Dy; T=V and Cr)

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Journal of Materials Science & Technology 1999年第1期15卷 5-9页

作者： Xiufeng HAM and Lanyng LIN(Materials Science center, Institute of Semiconductors, Chinese Academy of Sciences, beijing 100083, {2.)T.Miyazaki(Dept. of Applied Physics, Faculty of Engineering, Tohoku university, Sendai 980-77, Japan)Fuming YANG(Institute Materials Science center Institute of Semiconductors Chinese Academy of Sciences Beijing 100083 China Dept. of Applied Physics Faculty of Engineering Tohoku University Sendai 980-77 Japan Institute of Physics Chinese Academy of Sciences Beijing 100080 China Materials Department Zhejiang University Hangzhou 310027 China

A systematic study of the phase formation, structure and magnetic properties of the R3Fe2.-xTxcompounds (R=Y, Ce, Nd, Sm, Gd, Tb, and Dy; T=V and Cr) has been performed uponhydrogenation. The lattice constants and the unit cell volume of R3Fe2.-xTxHy decrease withincreasing R atomic number from Nd to Dy, except for Ce, reflecting the lanthanide *** anisotropic expansions mainly along the a- and b-axis rather than along the c-axis areobserved for all of the compounds upon hydrogenation. Hydrogenation leads to an increase inthe Curie temperature and a corresponding increase in the saturation magnetization at roomtemperature for each compound. First order magnetization processes (FOMP) occur in theexternal magnetic fields for Nd3Fe2..5Cr4.5H5.0, Tb3Fe2..0Cr2.0H2.8, and Gd3Fe2..0Cr1.0H4.2.ompounds

关键词： Hydrogenation and Anisotropic Expansions in R3Fe x)T_x R=Y Ce Sm Gd Nd

SYNTHESIS AND APPLICATION OF NANOPARTICLES BY A HIGH GRAVITY METHOD

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Particuology 2005年第Z1期 134-135页

作者： Lei Shao and Jianfeng Chen Key Lab for Nanomaterials, Ministry of Education, beijing university of Chemical Technology, beijing 10002., P. R. china Research center of the Ministry of Education for High Gravity Engineering and Technology, beijing university of Chemical Technology, beijing 10002., P. R. china

Fast chemical reactions involved in nanomaterials synthesis, polymerization, special chemicals production, reactive absorption, etc., are often difficult to control in terms of product quality, process efficiency and production consistency. After a theoretical analysis on such processes based on chemical reaction engineering fundamentals, an idea to intensify micromixing (mixing on the molecular scale) and mass transfer and therefore to control the process ideally was proposed. By experimental investigations of mass transfer and micromixing characteristics in the Rotating Packed Bed (RPB, or "HIGEE" device), we achieved unique intense micromixing. This led us to the invention of using RPB as a reactor for the fabrication of nanoparticles (Chen et al., 2.00).

关键词： nanoparticles high gravity method rotating packed bed synthesis application

HYPERBRANCHED AROMATIC POLYMERS OBTAINED VIA SELF-CONDENSATION

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Chinese Journal of Polymer Science 2001年第5期19卷 517-520页

作者： Xi Zhang Yong-ming Chen Dong-yan Wang Jing Jiang Hong-wei Liu Chuan-fu Chen Fu Xi center for molecular Science, Institute of Chemistry Chinese Academy of Sciences, {2. 100080, china The State Key Laboratory of Functional Polymer Materials for Adsorption and Separation, Nankai university Tianjin 300071, china 中科院化学所北京南开大学吸附分离功能高分子材料国家重点实验室天津

Hyperbranched aromatic polymers were prepared by Friedel-Crafts reaction with Lewis acid, AlCl3 and ZnCl2. as the catalysts. In this work, hyperbranched polybenzyl (PB) and poly(methylene)naphthalene (PN) were synthesized and characterized by H-1-NMR and GPC. In addition, their florescence properties were measured with steady-state florescence spectra in THF and ethylene dichloride. The quantum yields of polybenzyl and poly(methylene)naphthalene in ethylene dichloride are much larger than those in THE.

关键词： hyperbranched polymer polybenzyl poly(methylene)naphthalene fluorescent spectra

VERTICAL HEREDITY VS. HORIZONTAL GENE TRANSFER: A CHALLENGE TO BACTERIAL CLASSIFICATION

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Journal of Systems Science & Complexity 2003年第3期16卷 307-314页

作者： HAO Bailin(Institute of Theoretical Physics, Academy of Chinese Sciences, beijing 100080, china Senior International Fellow of the Santa Fe Institute T-Life Research {2., Fudan university,Shanghai 2.0433, china)QI Ji(Institute of Theoretical Physics, beijing 100080, china) Institute of Theoretical Physics Academy of Chinese Sciences 北京 100080 Institute of Theoretical Physics Chinese Academy of Sciences 北京 100080

The diversity and classification of microbes has been a long-standing *** phylogeny of the prokaryotes based on comparison of the 16S rRNA sequences of the small ribosomal subunit has led to a reasonable tree of life in the late 1970s. How-ever, the availability of more and more complete bacterial genomes has brought about complications instead of refinement of the tree. In particular, it turns out that different choice of genes may tell different history. This might be caused by possible horizontal gene transfer (HGT) among species. There is an urgent need to develop phylogenetic methods that make use of whole genome data. We describe a new approach in molecular phylogeny,namely, tree construction based on K-tuple frequency analysis of the genomic *** aside the technicalities, we emphasize the transition from randomness to determin-ism when the string length K increases and try to comment on the challenge mentioned in the title.

关键词： prokaryote phylogeny horizontal gene transfer fitness compositionaldistance

Progress in phototaxis mechanism research and micromanipulatlon techniques of algae cells

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Progress in Natural Science:Materials International 2007年第3期 254-260页

作者： WEN Chenglu, LI Heng, WANG Pengbo, LI Wei and ZHAO Jingquan (. College of Engineering, china Agricultural university, {2. 100083, china Key Laboratory of Photochemistry, center for molecular Science, Institute of Chemistry, Chinese Academy of Sciences, {2. 100080, china)

Pholotaclic movement is a characteristic of some microorganisms' response to light environment. Most of the algae have dramatically phototactic responses, underlying the complicated biological, physical and photochemical mechanisms are involved. With the development of the micro/nano and sensor techniques, great progress has been made in the research of the algae phototaxis. This review article summarizes the progress made in the research on the functional phototactic structures, the mechanisms of photo-response process and photodynamics of phototaxis in algae, and describes the latest developed micro-tracking technique and micromanipulation technique. Moreover, based on our own research results, the potential correlation between the phototaxis and photosynthesis is discussed, and the directions for future research of the phototactic mechanism are proposed.

关键词： phototaxis algae photosynthesis tracking micromanipulation.

Ethylene oligomerization by novel iron(Ⅱ) diimine complexes/MAO

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Chinese Science Bulletin 2002年第19期47卷 1616-1618页

作者： WANG Hang, YAN Weidong, JIANG Tao, LIU Binbin, XU Wenqing, MA Jianjiang & HU YouliangState Key Laboratory of Engineering Plastics, center for molecular Science, Institute of Chemistry, Chinese Academy of Sciences, {2. 100080, china Graduate Student of State Key Lab. of Eng. Plastics Institute of Chemistry Chinese Academy of Sciences Beijing 100080 China Grad. Student Chinese Acad. of Sci. Beijing 100039 China Inst. of Polymer Science/Engineering School of Chemical Engineering Hebei University of Technology Tianjin 300130 China Dept. of Petrochemical Engineering Daqing Petroleum Institute Anda 151400 China Res. Inst. Dushanzi Petrochem. Co. PetroChina Xinjiang 833600 China

Two novel Fe(Ⅱ) diimine complexes have been synthesized. In combination with MAO, they generate active catalytic systems that oligomerize ethylene with both high catalytic activity and high selectivity for a-olefins. The effects of substituents on the aryl ring, reaction temperatures and molar ratios of Al/Fe on catalytic activity and product distribution are studied.

关键词： late-transition-metal catalysts ethylene oligomerization α-olefin.

NUMERICAL APPLICATION OF THE RECURSION METHOD TO THE ELECTRONIC STRUCTURE OF C60

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原子与分子物理学报 1997年第3期 25-29页

作者： Lu Jing Zhang LiyuanDepartment of Physics, Peking university, beijing 100871, P.R.{2.

采用Ｒｅｃｕｒｓｉｏｎ方法计算了Ｃ６０分子的能态密度，所得的能隙、能级的简并度及顺序与ＬＤＡ方法或者解析方法得到的结果吻合。

关键词： C60 电子结构