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Heat capacity and thermodynamical properties of the crystal of [RE_2.Glu)_2.H_2.)_8](ClO_4)_4·H_2. (RE = Nd, Eu, Dy)

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Science china chemistry 2009年第7期52卷 862-867页

作者： WU XinMin1, LI Wei1, TAN ZhiCheng2.& QU SongSheng3.1 Department of Chemical engineering, beijing Institute of Petro-chemical Technology, beijing 102.17, china 2.Thermochemistry Laboratory, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 11602., china 3.college of chemistry and molecular Science, Wuhan {13., Wuhan 43.072. china Department of Chemical engineering Beijing Institute of Petro-chemical Technology Beijing China Thermochemistry Laboratory Dalian Institute of Chemical Physics Chinese Academy of Sciences Dalian China college of chemistry and {2. Science Wuhan University Wuhan China

Thermodynamical data of rare earth complexes with amino acid are important for engineering chemistry and fundamental chemistry. However, they have rarely been reported. In this work, a series of crystalline complexes of rare earth perchlorate coordinated with glutamic acid have been synthesized in water medium, and their thermodynamical data, including the heat capacity in low temperature range and the standard enthalpy of formation, were determined. These complexes were identified to be [RE{3.Glu){3.H{3.)8](ClO4)4·H{3. (RE = Nd, Eu, Dy) by using thermogravimetric analysis (TG), differential thermal analysis (DTA), and chemical and elementary analyses. Their purity has been determined. No melting points were observed for all the three complexes. The heat capacity of the complexes was measured by an adiabatic calorimeter from 79 to 3.0 K. Abnormal heat capacity values were detected for two of the complexes and the decomposition range of one complex was found. The temperature, enthalpy change and entropy change of the decomposition processes of the three complexes were calculated. The polynomial equations of heat capacity in the experimental temperature range have been obtained by least squares fitting. The standard enthalpy of formation was determined by an isoperibol reaction calorimeter at {3.8.15 K.

关键词： complex of rare earth, [RE2.Glu)2.H2.)8](ClO4)4·H2. (RE = Nd, Eu, Dy Glu = glutamic acid), low-temperature heat capacity, standard enthalpy of formation

A Comparison of Three Heuristic Algorithms for molecular Docking

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Chinese Chemical Letters 1999年第7期10卷 615-618页

作者： Ting Jun HOU Jun Mei WANG Xiao Jie XU(Department of chemistry. Beida-Jiuyuan molecular Design Laboratory. {2..{3.) Department of chemistry Beida-Jiuyuan Molec. Des. Laboratory Peking University Beijing 100871 China

Three heuristic algorithms: simulated annealing, genetic algorithm, and Tabu search were compared to molecular docking procedure using 3.protein-ligand systems. Statistical analysis of the results indicated that the Tabu search showed the best performance in terms of locating solutions close to the crystallographic ligand conformation. From the comparisons, a hybrid search algorithm was proposed, which gave superior results compared with any one of the algorithms alone.

关键词： molecular docking genetic algorithm tabu search simulated annealing

SYNTHESIS OF DIACETYLENE-CONTAINING COPOLYESTERS AND THEIR DFFECT ON ELECTRO-OPTICAL PROPERTIES OF LIQUID CRYSTALS

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Chinese Journal of Polymer Science 1999年第2期17卷 193-196页

作者： Xiao-fang Chen Yao-wen Bai Yu-guo Ma Chen-hui Wang Dong Zhang Xin-hua Wan Qi-feng Zhou Department of Polymer Science and engineering, college of {2., {3., beijing 100871, china 北京大学化学院北京 100871 北京大学化学院北京

Some diacetylene-containing copolyesters with different ratios of dipropargyl 1,10-decanate anddipropargyl terephthalate were synthesized. Properties of these copolymers were characterized by differentialscanning calorimetry and polarizing optical microscopy. The copolymer could be cross-linked easily by UVirradiation in a liquid crystal matrix without adding any photoinitiator. The preliminary studies showed thatthe diacetylene-containing polymer network can assist liquid crystal molecules to align with the externalelectric field, thus reducing the response time of display devices.

关键词： Diacetylene-containing copolyesters Polymer-stabilized liquid crystals Electo-optical of liquid crystals

Application of Genetic Algorithm to the QSAR Research of Pyrrolobenzothiazepinones and Pyrrolobenzoxazepinones-Novel and Specific Non-Nucleoside HIV-1 Reverse Transcription Inhibitors

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Chinese Chemical Letters 1998年第7期9卷 651-654页

作者： Ting Jun HOU Jun Mei WANG You Yong LI Xiao Jie XU(chemistry department, Beida-Jiuyuan molecular Design Laboratory, {2.,{3.) chemistry Department Beida-Jiuyuan Molec. Des. Laboratory Peking University Beijing 100871 China

Genetic Algorithm (GA) was used to study the quantitative structural parameters and activity relationship of pyrrolobenzothizepinones and pyrrolobenzoxazepinones's inhibitory activities with non-nucleoside HIV-1 reverse transcriptase (RT). A group of linear polynomial models with good relationship have been built to get some useful information that other methods can not offer.

关键词： QSAR GA(genetic algorithm) HIV

Cytotoxicity, apoptosis induction, and mitotic arrest by a novel podophyllotoxin glucoside, 4DPG, in tumor cells

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Acta Pharmacologica Sinica 2005年第8期26卷 1000-1008页

作者： Yi-lin QI~(2.4), Fan LIAO~(2.4), Chang-qi ZHAO~2. Yong-da LIN~2. Ming-xue ZUO~(2.3.5) ~2.college of Life Sciences, beijing Normal {2., beijing 100875 china ~3.Key Laboratory for molecular Biology and Gene engineering Drugs of beijing, beijing 100875, china college of Life Sciences Beijing Normal University Beijing China Key Laboratory for molecular Biology and Gene engineering Drugs of {2. Beijing China

Aim: To define the in vitro cytotoxic activities of 4-demethyl-picropodophyllotoxin 7'-O-β-D-glucopyranoside （4DPG）, a new podophyllotoxin glucoside. Methods: Antiproliferation activity was measured in several tumor cell lines by using the microculture tetrazolium MTT assays. Cell cycle distribution was analyzed using flow cytometry and mitosis index assays. Furthermore, transmission electron microscopy, TUNEL, DNA agarose electrophoresis, and activated caspase-3.were used to analyze the induction of apoptotic cell death. Moreover, intracellular changes in the cytoskeleton were detected using immunocytochemistry. Results: 4DPG effectively inhibited the proliferation of cancer cells （HeLa, CNE, SH-SY5Y, and K562.cell lines）. For the K562.cell line, the antiproliferation effect of 4DPG was much more potent than that of etoposide (IC50value: 7.79x10（-9） mol/L for 4DPG vs 2.2.x 10（-5） mol/L for etoposide). Further, 4DPG blocked the cell cycle in the mitotic phase. The induction of apoptosis and elevated levels of activated caspase-3.were confirmed in cells treated with 4DPG. The microtubule skeleton of HeLa cells was disrupted immediately after treatment with 4DPG. Conclusion: The cytotoxicity of 4DPG is due to its inhibition of the microtubule assembly of cancer cells at a low concentration, thus inducing apoptosis. These properties qualify 4DPG to be a potential antitumor drug.

关键词： 4-demethyl-picropodophyllotoxin 7’-O-β-D-glucopyranoside podophyllotoxin flow cytometry microtubulin apoptosis

Synthesis and Steric Structure of β-Lactam Derivatives of 2.4-Diaryl-2.3.dihydro-1,5-benzothiazepines

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Chinese Chemical Letters 1998年第10期9卷 919-921页

作者： Qi Yi XING Yuan LI Cat Yun DU Qiu Qing YANGNa SUN, Sheng JIN(Bioorganic molecular engineering Laboratory, Institute of {2. and molecular engineering, peking university, beijing 100871 Department of {2., Experiment Center, Hebei Normal Unive Bioorg. Molec. Eng. Laboratory Inst. of Chem./Molecular Engineering Peking University Beijing 100871 China Department of chemistry Experiment Center Hebei Normal University Shijiazhuang 050016 China Department of Basic Course Hebei Handan Agricultural College Handan 056000 China

This paper reports the primary results of the study on β-lactam derivatives of 2.4-diaryl-2. 3.di hydro-1, 5 -benzothiazepines. Five titie compounds have been synthesized, and their configUration and conformation wer... 详细信息

关键词： 1,5-benzothiazopine β-lactam Cycloaddition

A mixed method for measuring low-frequency acoustic properties of macromolecular materials

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Science china(Physics,Mechanics & Astronomy) 2006年第6期49卷 729-739页

作者： LIU Hongwei1,YAO Lei1,3.ZHAO Hong1,3.ZHANG Jichuan2.3.& XUE Zhaohong2.1. National Key Laboratory of Acoustics,Institute of Acoustics,Chinese Academy of Sciences,beijing 100080,{3. 2. Institute of {2.,Chinese Academy of Sciences,beijing 100080,{3. 3. Graduate university of Chinese Academy of Sciences,beijing 100049,{3. National Key Laboratory of Acoustics Institute of Acoustics Chinese Academy of Sciences Beijing China Graduate university of Chinese Academy of Sciences Beijing China Institute of chemistry Chinese Academy of Sciences Beijing China

A mixed method for measuring low-frequency acoustic properties of macro-molecular materials is presented. The dynamic mechanical parameters of materials are first measured by using Dynamic Mechanical Thermal Apparatus(DMTA) at low frequen-cies,usually less than 100 Hz; then based on the Principles of Time-Temperature Super-position (TTS),these parameters are extended to the frequency range that acousticians are concerned about,usually from hundreds to thousands of hertz; finally the extended dynamic mechanical parameters are transformed into acoustic parameters with the help of acoustic measurement and inverse analysis. To test the feasibility and accuracy,we measure a kind of rubber sample in DMTA and acquire the basic acoustic parameters of the sample by using this method. While applying the basic parameters to calculating characteristics of the sample in acoustic pipe,a reasonable agreement of sound absorp-tion coefficients is obtained between the calculations and measurements in the acoustic pipe.

关键词： low-frequency acoustic properties,dynamic mechanical properties,Principles of Time-Temperature Superposition,acoustic pipe,sound absorption coefficient.

Further study of sources of the imported cobalt-blue pigment used on Jingdezhen porcelain from late 13.to early 15 centuries

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Science china(Technological Sciences) 2008年第3期51卷 249-259页

作者： DU Feng1 & SU BaoRu2.1 Institute of chemistry & molecular {2., Qingdao university of Science & Technology, Qingdao 2.6000, china 2.college of Information Science Technology, Qingdao university of Science & Technology, Qingdao 2.6000, china Institute of chemistry & molecular {2. Qingdao University of Science & Technology Qingdao China college of Information Science Technology Qingdao University of Science & Technology Qingdao China

Based on the conclusion of modern scientific analysis: the cobalt-blue pigment applied on Jingdezhen official porcelain during Yuan Dynasty and prior to Xuande reign of Ming Dynasty (12.1―142.) contains high iron and low manganese con- tents, and the cobalt during Xuande and after Xuande periods (after 142.) of Ming Dynasty contains high manganese and low iron contents, in combination with the traditional archaeological method, the related historical textual records were in- vestigated and analyzed, the imported cobalt employed on Jingdezhen official porcelain was studied comprehensively, systematically and logically. In fact, 'Su Ma Li Qing' (Samarra-blue) and 'Su Bo Ni Qing' (Sumatra-blue) are definitely different cobalt ores originated in different places, because of their very similar translitera- tions in Chinese, the confusion has appeared in ancient books for more than 400 years, which considered 'Su Ma Li Qing' and 'Su Bo Ni Qing' as the same co- balt-blue pigment. In this article the mistake was corrected, the possible producing places and the approximate eras of the two pigments imported to {3. and used at Jingdezhen were also suggested.

关键词： imported cobalt-blue pigments employed on official blue-and-white porcelain Yuan Dynasty early Ming Dy- nasty Mn/Fe content ratio Su Ma Li Qing (Samarra-blue) Su Bo Ni Qing (Sumatra-blue) scientific archae- ological research transliteration

SiO/CNTs:A new anode composition for lithium-ion battery

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Science china chemistry 2009年第12期52卷 2047-2050页

作者： REN YuRong1,2.3.,QU MeiZhen1 & YU ZuoLong1 1 Chengdu Institute of Organic chemistry,Chinese Academy of Sciences,Chengdu 610041,china 2.{2. of chemistry,Jilin Normal university,Siping 13.000,china 3.Graduate university of Chinese Academy of Sciences,beijing 10003.,china Chengdu Institute of Organic chemistry Chinese Academy of Sciences Chengdu China college of chemistry Jilin Normal University Siping China Graduate university of Chinese Academy of Sciences Beijing China

A new anode composition SiO/CNTs (carbon nanotubes) has been prepared by chemical vapor deposition (CVD) method. The results of scanning electron microscopy (SEM) confirm that CNTs deposit on small SiO particles,form a cage,and enwrap SiO particles tightly. SiO/CNTs anode composition exhibits an initial discharge and charge capacity of 1171 and 789 mAh/g,and maintains a reversible capacity of 500 mAh/g after 80 cycles. The improvement of the cyclic performance for SiO/CNTs composition is related to the maintaining of the electric network during cycling,which benefits from a tight contact between CNTs and SiO particles.

关键词： SiO/CNTs CVD composition anode Li-ion battery