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Science china chemistry 2006年第4期49卷 338-344页

作者： TAO Ruojie1, LI Fu’an1, ZANG Shuangquan1, CHENG Yanxiang2.& NIU Jingyang1 1. chemistry and Chemical Engineering College of Henan University, Kaifeng 475001, china 2. {2. Institute of applied chemistry, chinese academy of sciences, changchun 13002., china 1. chemistry and Chemical Engineering College of Henan University Kaifeng 475001 China 2. changchun Institute of applied {2. Chinese Academy of Sciences Changchun 130022 China

Copper-zinc heterometallic 1D chain coordination polymer has been synthesized and characterized by elemental analysis, and IR spectra etc. The crystal structure was determined by single-crystal X-ray diffraction analyses. The title complex is 1D chain coordination polymer with the chemical formula {[CuLZn·CuLZn(H2.)]·H2.}n, where H4L=N-(2.hydroxybenzamido)-N’-(3-carboxy- lsalicylidene)ethylenediamine. Its structural unit is comprosed of two tetranuclear cycles formed by two dissymmetrical tetranuclear units. These units polymerized each other to form 1D chain coordi- nation polymer.

关键词： copper, zinc, heterometallic coordination polymer, crystal structure.

Kumada chain-growth polycondensation as a universal method for synthesis of well-defined conjugated polymers

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Science china chemistry 2010年第8期53卷 1620-1633页

作者： GENG YanHou1,HUANG Li1,2.WU ShuPeng1,2.& WANG FoSong1 1State Key Laboratory of Polymer Physics and chemistry changchun Institute of {2. chemistry,chinese academy of sciences,changchun 13002.,china 2.raduate University of chinese academy of sciences,Beijing 100049,china 1. State Key Laboratory of Polymer Physics and chemistry changchun Institute of applied {2. Chinese Academy of Sciences Changchun 130022 China2. Graduate University of Chinese Academy of Sciences Beijing 100049 China

Kumada chain-growth polycondensation (KCGP) is a novel method for the synthesis of well-defined conjugated *** the Ni-catalyst can transfer in an intramolecular process to the propagating chain end,the polymerization follows chain-growth *** this newly developed method,various conjugated polymers,such as polythiophenes,poly(p-phenylene) (PPP),polypyrrole (PPy),and polyfluorene with controlled molecular weights and relatively narrow polydispersities (PDIs),have been ***,the polymerizations for poly(3-alkylthiophene)s (P3ATs),PPP,and PPy exhibited quasi-living characteristics,which allows preparing polymer brushes,fully-conjugated block copolymers,and macroinitiators and macro-reactants for the synthesis of rod-coil block *** the current review,the progress in this new area is summarized.

关键词： chain growth polycondensation conjugated polymers Kumada reaction block copolymers polymer brush

MELTING CRYSTALLIZATION BEHAVIOR OF NYLON 66

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chinese Journal of Polymer Science 2001年第3期19卷 237-246页

作者： Qing-xin Zhang Zhi-shen Mo State Key Laboratory of Polymer Physics & chemistry changchun Institute of {2. chemistry chinese academy of sciences, changchun 13002., china chinese Acad Sci Changchun Inst Appl Chem State Key Lab Polymer Phys & Chem Changchun 130022 Peoples R China

Analysis of isothermal and nonisothermal crystallization kinetics of nylon 66 was carried out using differential scanning calorimetry (DSC). The commonly used Avrami equation and that modified by Jeziorny were used, respectively, to fit the primary stage of isothermal and nonisothermal crystallizations of nylon 66. In the isothermal crystallization process, mechanisms of spherulitic nucleation and growth were discussed. The lateral and folding surface free energies determined from the Lauritzen-Hoffman treatment are sigma = 9.77 erg/cm(2. and sigma (e) = 155.48 erg/cm(2., respectively; and the work of chain folding is q = 33.14 kJ/mol. The nonisothermal crystallization kinetics of nylon 66 was analyzed by using the Mo method combined with the Avrami and Ozawa equations. The average Avrami exponent (n) over bar was determined to be 3.45. The activation energies (DeltaE) were determined to be -485.45 kJ/mol and -331.2. kJ/mol, respectively, for the isothermal and nonisothermal crystallization processes by the Arrhenius and the Kissinger methods.

关键词： nylon 66 crystallization kinetics activation energy

Luminescence of RE^(3+) and energy transfer from Gd^(3+) to RE^(3+) (RE = Dy, Eu) in SrGdAlO_4:RE^(3+)

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chinese Journal of chemistry 1997年第1期15卷 60-67页

作者： LIU, Sheng-Li SU, QiangLaboratory of Rare Earth chemistry and Physics, changchun Institute of {2. chemistry, chinese academy of sciences, changchun, Jilin 13002., china Laboratory of Rare Earth chemistry and Physics Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun Jilin 130022 China [*]Laboratory of Rare Earth chemistry and Physics Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun Jilin 130022 China

Spectral properties of Gd3+, Dy3+ and Eu3+ ions in SrGdAlO4 are reported in detail. A cooperative vibronic transition of Gd3+ and the emission from the higher 5DJ (J=1, 2. 3) levels of Eu3+ were observed. Energy transfer occurs from Gd3+ to Dy3+ and to Eu3+. The influence of Gd3+ and Dy3+ concentrations on the luminescence intensity is discussed.

关键词： Luminescence energy transfer rare earth aluminate

Study on polymerization and structure of polydiphenylamine

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chinese Journal of chemistry 1994年第2期12卷 138-147页

作者： JIN, Wen SONG, Fa-Yi DONG, Shao-JunLaboratory of Electroanalytical chemistry, changchun Institute of {2. chemistry, chinese academy of sciences, changchun, Jilin 13002., china Laboratory of Electroanalytical chemistry Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun Jilin 130022 China

The electrochemical oxidation of diphenylamine in acetonitrile produces an adherent uniform polymer film which exhibits mutiple colour variation(yellow-green-blue) in a wide range of potential scan. The polymerization mechanism and the structure of the polymer were studied by cyclic voltammetry, FT-IR and in situ ESR. The results indicate that the electrochemical polymerization of diphenylamine belongs to a cationic radical polymerization process. During electrolysis, only oligomers were initialy produced, then polymer film was formed on the electrode surface. The electropolymerization performs via the 4,4' C-C phenyl-phenyl coupling mechanism.

关键词： DPA electrochemical polymerization mechanism ESR.

Analysis of Low-polar Ginsenosides in Steamed Panax Ginseng at High-temperature by HPLC-ESI-MS/MS

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Chemical Research in chinese Universities 2012年第1期28卷 31-36页

作者： ZHANG Yu-chi1,2. PI Zi-feng1, LIU Chun-ming2. SONG Feng-rui1, LIU Zhi-qiang1 and LIU Shu-ying1 1. changchun Center of Mass Spectrometry, changchun Institute of {2. chemistry, chinese academy of sciences, changchun 13002., P. R. china 2. Central Laboratory, changchun Normal University, changchun 130032. P. R. china chinese Acad Sci Changchun Inst Appl Chem Changchun Ctr Mass Spectrometry Changchun 130022 Peoples R China changchun Normal Univ Cent Lab Changchun 130032 Peoples R China

A high performance liquid chromatography coupled with electrospray ionization-tandem mass spectrome try（HPLC-ESI-MS/MS） method was developed for the analysis and identification of ginsenosides in the extracts of raw Panax ginseng（RPG） and steamed Panax ginseng at high temperatures（SPGHT）. A total of 2. ginsenosides were extracted include of which 10 low-polar ginsenosides, such as ginsenosides F4, Rk3, Rh4, 2.S-Rg3, 2.R-Rg3 and so on, were identified according to their HPLC retention time and MS/MS data. The results indicated that the low polar ginsenosides were seldom found in RPG. For the exploration of the transformation pattern of the ginsenosides in steam processing, the standards of ginsenosides Re, Rg1, Rb1, Rc, Rb2. Rb3 and Rd were selected and hydrolyzed at a temperature of 12. oC. The results show that these polar ginsenosides can be converted to low-polar ginsenosides such as Rg2. Rg6, F4, Rk3 and Rg5 by hydrolyzing the sugar chains.

关键词： Ginsenoside Hydrolysis Steamed Panax ginseng High performance liquid chromatography coupled withelectrospray ionization-tandem mass spectrometry(HPLC-ESI-MS/MS)

Luminescent properties of Ba_3(PO_4)_2.Eu,Tb phosphors

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chinese Journal of chemistry 1996年第5期14卷 399-403页

作者： GAO,Yong SHI,Chun-ShanLaboratory of Rare Earth chemistry and Physics,changchun Institute of {2. chemistry,chinese academy of sciences,changchun,Jilin 13002.,china Laboratory of Rare Earth chemistry and Physics Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun Jilin 130022 China

Luminescence of europium (Ⅲ),europium(Ⅱ) and terbium(Ⅲ) has been observed in Bas(PO4)2.Eu,Tb phosphors which are synthesized in air *** valence state of europium is influenced by amount of *** is notable that the relative intensity of the emission spectra peaks corresponding to Eu2. is increased if the amount of Tb3+ is *** phenomena can be explained by an electron transfer *** predict a new kind of two-rare-earth codoped trichromatic phosphors in Ba3(PO4)2.matrix.

关键词： Luminescence europium terbium phosphor

Synthesis and characterization of a pH-sensitive shielding system for polycation gene carriers

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Science china chemistry 2010年第3期53卷 502-507页

作者： XIA JiaLiang1,2.CHEN Jie1,TIAN HuaYu1 & CHEN XueSi1 1Key Laboratory of Polymer Ecomaterials changchun Institute of applied {2.,chinese academy of sciences,changchun 13002.,china 2.raduate University of chinese academy of sciences,Beijing 100049,china 1. Key Laboratory of Polymer Ecomaterials changchun Institute of applied {2. Chinese Academy of Sciences Changchun 130022 China2. Graduate University of Chinese Academy of Sciences Beijing 100049 China

To increase the in vivo stability of polycation gene carriers,a pH-sensitive shielding system,γ-benzyl L-glutamate-co-glutamate acid polymer(PGA(60)(60 refers to the molar ratio of glutamate acid in the polymer)),was synthesized and ***(60) showed pH sensitivity at about pH ***(60) shielded the positive charge of DNA/PEI(1:1) *** retardation assay showed that no DNA-strand exchange with PGA(60) occurred after PGA(60) was added to DNA/PEI complexes at different *** cytotoxicity tests demonstrated that neither PGA(60) nor DNA/PEI/PGA(60) ternary complexes had cytotoxicity at the test *** transfection efficiency was improved when the positive charge was partly shielded by PGA(60).Because of the charge repulsion between the surface of cells and ternary complex particles,there was almost no transfection efficiency when the zeta potential of ternary complexes turned to *** of the suitable pH sensitive range,PGA(60) may be a potential shielding system for polycation gene carriers to be used in vivo.

关键词： gene delivery shielding system pH-sensitive polyglutamate

The Influence of Bond Valence on Bond Covalency in RMn_2._5 (R=La, Pr, Nd, Sin, Eu)

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chinese Chemical Letters 1999年第1期10卷 91-94页

作者： Zhi Jian WU Si Yuan ZHANG(changchun Institute of applied {2., chinese academy of sciences, changchun 13002.) chinese Acad Sci Changchun Inst Appl Chem Changchun 130022 Peoples R China

The relationship between bond valence and bond covalency in RMn2.5 (R = La, Pr, ***, Eu) has been investigated by a semiempirical method. This method is the generalization of thedielectric description theory of Phillips. Van Vechten, Levine and Tanaka scheme. The resultsindicate that larger valences usually result in higher bond covalencies, in good agreement with thepoint that the excess charge in the bonding region is the origin of formation of bond *** factors, such as oxidation state of elements, only make a small contribution to bondcovalency.

关键词： Bond valence bond covalency semiempirical method RMn_2._5

Thermal behavior and phase behavior in blends of liquid crystalline poly(aryl ether ketone) and poly(aryl ether ether ketone) containing thioether units

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Science china chemistry 2012年第4期55卷 612-617页

作者： LI Ye1, CHEN Jian2. LIU XinCai1 & YANG DeCai2.1Alan G. MacDiarmid Institute, Jilin University, changchun 130012. china 2.tate Key Laboratory of Polymer Physics and {2. changchun Institute of applied {2., chinese academy of sciences, changchun 13002., china 1. Alan G. MacDiarmid Institute Jilin University Changchun 130012 China2. State Key Laboratory of Polymer Physics and Chemistry changchun Institute of applied {2. Chinese Academy of Sciences Changchun 130022 China

Thermal behavior and phase behavior in blends of liquid crystalline poly(aryl ether ketone) with lateral methoxy groups (M-PAEK) and poly(aryl ether ether ketone) containing thioether units (S-PEEK) have been investigated by differential scanning calorimetry (DSC) and polarized light microscopy (PLM) techniques. The results indicate that the composition of the blends has great effect on the phase behavior and morphology. Thin films of pure M-PAEK and S-PEEK crystallized from the melts exhibit typical mosaic and spherulitic structures, respectively. For the blends with higher M-PAEK contents (> 50%), an unusual ring-banded spherulite with structural discontinuity is formed. The bright core and rings of the ring-banded spherulites under PLM are composed of M-PAEK phase, while the dark rings consist mainly of S-PEEK phase. For the 50:50 M-PAEK/S-PEEK blend, the ring-banded spherulites and S-PEEK spherulites coexist, which implies that a partial phase separation between the two components takes place in the melting state. In S-PEEK-rich blends, a volume-filled spherulite is produced. In addition, the effect of isothermal crystallization temperature on the phase behavior, especially the ring-banded spherulite formation in the blends, is discussed.

关键词： liquid crystalline poly(aryl ether ketone) – poly(aryl ether ether ketone) containing thioether units – phase behavior – rhythmically grown ring banded spherulite