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Phase Transition Temperature of HPT(2,3,6,7,10,11-hexa-n-pentyloxytriphenylene) from Molecule Dynamic Simulation

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chinese Chemical Letters 1998年第3期9卷 299-304页

作者： Jun LUO Tao WANG Su Sheng TAN En Le ZHOU(Polymer Physics Laboratory, changchun institute of applied chemistrychinese academy of sciences, changchun, 130022) Polymer Physics Laboratory Changchun Institute of Applied Chem. Chinese Academy of Sciences Changchun 130022 China

Molecule dynamics simulation was used on HPT(2,3,6,7,10,11-hexa-n-pentyloxytriphenylene), which is a discotic Liquid crystal. From analyzing the energy and displacement varying with the temperature, the phase transition temperature of PM6MPP can be predicted. The deviations of T-g, T-m and T-i due to the MD time scale are small enough that it should be possibly used to predict the material properties especially when more powerful computers are available.

关键词： phase transition temperature molecule dynamic simulation discotic liquid crystal

~1H and ^(13)C NMR studies of TTHA complexes with diamagnetic rare earth ions

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chinese Journal of chemistry 1995年第5期13卷 429-434页

作者： ZHANG, Shan-Rong REN, Ji-Min PEI, Feng-Kui LIU, Ai-Zhuo XIAO, Yan-Wenapplied Spectroscopy Laboratory, changchun institute of applied chemistry, chinese academy of sciences, changchun, Jilin 130022, china applied Spectroscopy Laboratory Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun Jilin 130022 China

TTHA complexes with diamagnetic rare earth ions (La3+, Y3+ and Lu3+) were studied by 1H and 13C NMR spectroscopy. A symmetric structural model was suggested for La(TTHA) complex and an asymmetric model for Y(TTHA) and Lu(TTHA) complexes. The complex formation was dependent on the pH value of the solution. The interactions of La(TTHA) with the additional metal ions (La3+, Y3+ and Ca2+) were relatively weak, but relatively strong for that of Lu(TTHA) with the additional Lu3+.

关键词： NMR TTHA diamagnetic rare earth ions

X-ray Crystal Structure and Molecular Mechanics Calculations of (2,6-iso-dipropyl-phcnylamidc) Dimethyl (tetra-methylecyclopenta- dienyl)Silane Titanium Dichloride

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chinese Chemical Letters 2000年第5期11卷 459-462页

作者： Tai Qi LIU Da Wei GUO Yong Hua LIN Xiao Zhen YANG You Liang HU (Center for Molecular Science. institute of chemistry. chinese academy of sciences. Beijing 100080 changchun institute of applied chemistry,chinese academy of sciences, changchun 130021) Center for Molecular Science Institute of Chemistry Chinese Academy of Sciences Beijing 100080 China changchun Inst. of applied chemistry Chinese Academy of Sciences Changchun 130021 China

Crystal and molecular structure of (2.6-dipropylphenylamidc) dimethyl (tetra-methyl cyclopentadienyl) silane titanium dichloride (I) was fully characterized by X-ray diffraction. The crystal is obtained tyom a mixture of ether/hexane as orthorhombic, with a = 12.658 (3 ) A. b = 16.62 (3) A. c = 11 .760 (2) A. V = 2474,2 (9) A. Z = 4. space group Pnma. R = 0.0399. Compound I compose of the R -bounded ring with its dimethylsilyl-dipropyl phenyl amido group and the two terminal chloride atoms coordinated to central metal to form a so-called constrained geometry catalyst (CGC) structure. The result of molecular mechanics (MM) calculations on compound I shows that bond lengths and bond angles from the MM calculation are comparable to the data obtained from the X-ray diffraction study. The relation of the structure of CGCs and their catalytic activity by MM calculations is also discussed.

关键词： Crystal structure constrained geometry catalyst metallocene molecular mechanics calculation.

EASTMAN-AQ/Ni(II)MODIFIED ELECTRODE DETECTION OF CARBOHYDRATES AND AMINO ACIDS

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chinese Chemical Letters 1993年第4期4卷 347-350页

作者： An Hua LIU Er Kang WANG LAboratory of Electroanalytical chemistry,changchun institute of applied chemistry,chinese academy of sciences,changchun,Jilin 130022

An Eastman-AQ/Ni(II)chemically modified electrode(CME) produced by“double coating steps”deposition of Eastman-AQ/Ni(II) film and Ni(II)-coating crystalline species onto glassy carbon instead of metallic nickel electrode exhibited stable electrocatalytic oxidation of numerous ∝-hydrogen compounds including carbohydrates, amines and amino *** of glucose in FIA on the CME, the linear response concentration range was bstween 1.0×10^(-5) and 5.0×10^(-2) mol/L and the detection limit was 5.0×10^(-6)mol/*** stability of the CME was adequate for routine quantitative application.

关键词： AQ EASTMAN-AQ/Ni CHE II)MODIFIED ELECTRODE DETECTION OF CARBOHYDRATES AND AMINO ACIDS CME SCE

Synthesis and Properties of Three Tris(1,10-phenanthroline) ruthenium (Ⅱ) Derivatives

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chinese Chemical Letters 1999年第10期10卷 881-884页

作者： Fa Ming TIAN Peng WANG Guo Yi ZHU (Laboratory of Electroanalytical chemistry, National Analytical Research Center ofElectrochemistry and Spectroscopy, changchun institute of applied chemistry,chinese academy of sciences, changchun 130022) Lab. of Electroanalytical chemistry Natl. Analyt. Res. Ctr. E. Chinese Academy of Sciences Changchun 130022 China

Three new asymmetrical ruthenium (Ⅱ) complexes :[Ru(phen)2{phen-NHCO(CH2)4BR}](pf6)2,[rU(PHEN)2{PHEN-nhco(ch2)5br}](pf6)2 and [Ru(phen)2{phen-NHCO(CH2)10Br}](PF6)2 were synthesized ,which were confirmed byh the technique of FT-IR 1HNMR and ESI-MS ,The electrochemical and fluorescent properties of three Ru(Ⅱ)complexes were investigated with cyclic voltammetry and fluorometry.

关键词： Tris(1.10-phenanthroline)ruthemium(Ⅱ) complexes synthesis electrochemistry fluorescence

Effect of strontium substitution on the activity of La_(2-x)Sr_xNiO_4(x=0.0-1.2)in NO decomposition

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Science china chemistry 2007年第1期50卷 41-46页

作者： ZHU JunJiang 1 ,YANG XiangGuang 2 ,XU XueLian 3 &WEI KeMei 1 1 National Research Center of Chemical Fertilizer Catalysts,Fuzhou University,Fuzhou 350002,china 2 changchun institute of applied chemistry,chinese academy of sciences,changchun 130022,china 3College of chemistry&Chemical Engineering,Fuzhou University,Fuzhou 350002,china National Research Center of Chemical Fertilizer Catalysts Fuzhou University Fuzhou China changchun institute of applied chemistry Chinese Academy of Sciences Changchun China College of chemistry & Chemical Engineering Fuzhou University Fuzhou China

The aim of this work is to study the effect of Sr substitution on the redox properties and catalytic ac- tivity of La2-xSrxNiO4(x=0.0-1.2)for NO *** suggest that the x=0.6 sample shows the highest *** characterization(TPD,TPR,etc.)of samples indicates that the x=0.6 sample possesses suitable abilities in both oxidation and reduction,which facilitates the proceeding of oxygen desorption and NO *** temperature below 700℃,the oxygen desorption is difficult, and is the rate-determining step of NO *** the increase of reaction temperature(T> 700℃),the oxygen desorption is favorable and,the active adsorption of NO on the active site(NO+Vo+ Ni2+→NO^--Ni3+)turns out to be the rate-determining *** existence of oxygen vacancy is the prerequisite condition for NO decomposition,but its quantity does not relate much to the activity.

关键词： NO decomposition La2-xSrxNiO4 TPD TPR oxygen vacancy

Systematic study of the transfer of amino acids across the water/1,2-dichloroethane interface facilitated by dibenzo-18-crown-6

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Science china chemistry 2004年第1期47卷 24-33页

作者： CHEN Yong, YUAN Yi, ZHANG Meiqin, LI Fei, SUN Peng, GAO Zhao & SHAO YuanhuaState Key Laboratory of Electroanalytical chemistry, changchun institute of applied chemistry, chinese academy of sciences, changchun 130022, china College of chemistry and Molecular Engineering, Peking University, Beijing 100871, china Lab. of Electroanalytical Chem. Changchun Inst. of Appl. Chem. Chinese Acad. of Sci. Changchun 130022 China Coll. of Chem. and Molecular Eng. Peking Univ. Beijing 100871 China

Facilitated ion transfer reactions of 20 amino acids with dibenzo-18-crown-6 (DB18C6) at the water/1,2-dichloroethane (W/DCE) interfaces supported at the tips of micro- and nano-pipets were investigated systematically using cyclic voltammetry. It was found that there were only 10 amino acids, that is, Leu, Val, lie, Phe, Trp, Met, Ala, Gly, Cys, Gin (in brief), whose protonated forms as cations can give well-defined facilitated ion transfer voltammograms within the potential window, and the reaction pathway was proven to be consistent with the transfer by interfacial complexation/dissociation (TIC/TID) mechanisms. The association constants of DB 18C6 with different amino acids in the DCE (β0), and the kinetic parameters of reaction were evaluated based on the steady-state voltammetry of micro- or nano-pipets, respectively. The experimental results demonstrated that the selectivity of complexation of protonated amino acid by DB18C6 compared with that of alkali metal cations was low, which can be attributed to the vicinal effect arising from steric hindrance introduced by their side group and the steric bulk effect by lipophilic stabilization. Moreover, the association constants and the standard rate constants for different amino acids showed good correlations with their hydrophobicity (π), except Gly and Met, which inferred that the selectivity of such heterogeneous complex reaction for different amino acids with DB18C6, was not only affected by discrimination in binding these ions to the crown ether macro-cycle, but also significantly modified by the ion transfer Gibbs energy which was closely related to the structure of the transferred ions, protonated amino acids.

关键词： micro-/nano-pipet, water/1,2-dichloroethane interface, facilitated ion transfer, cyclic voltammetry, amino acid.

Studies on the Coordination of Pr(Ⅲ) with Adrenaline by Potentiometry and Absorption Spectroscopy

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chinese Chemical Letters 1999年第8期10卷 677-678页

作者： Feng GAO Jing Fen HAN Zhi Jian WU Yue WANG Kui Yue YANG Chun Ji NIU Jia Zuan NI (Laboratory of Rare Earth chemistry and Physics. changchun institute of applied chemistry. chinese academy of sciences, changchun 130022) Lab. of Rare Earth Chem. and Physics Changchun Inst. of Applied Chemistry Chinese Academy of Sciences Changchun 130022 China

The stability constant for complex of Pr(Ⅲ) with adrenaline has been determined by potentiometric titration under biological conditions (37℃ and 0.15mol/L NaCl). The absorption spectra of the Pr(Ⅲ)-adrenaline system exhibit characteristic bands of Pr(Ⅲ) at lower pH values. However, the charge transfer band which is due to the coordination of Pr(Ⅲ) with adrenaline has been observed at higher pH values.

关键词： Praseodymium adrenaline potentiometry spectroscopy

Study on Alternating LB Films of Charge-Transfer Complex of Octadecyl-TCNQ and Copper Phthalocyanine Derivative

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chinese Chemical Letters 1997年第5期8卷 453-454页

作者： Han Ming DING Li Ying WANG Ying ZHANG Shi Quan XI(changchun institute of applied Chemistn. chinese Acaderny of sciences, changchun, 130022) changchun Inst. of applied chemistry Chinese Academy of Sciences Changchun 130022 China

Infrared spectra of alternating LB films of octadecyl-TCNQ/CuPc are studied. Charge-transfer complexes are formed in LB films and conductance increases about three orders than that of pure CuPc LB films.

关键词： TCNQ LB Study on Alternating LB Films of Charge-Transfer Complex of Octadecyl-TCNQ and Copper Phthalocyanine Derivative