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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 applied chemistry chinese academy of sciences, changchun 130022, china 中科院长春应用化学所高分子物理与化学国家重点实验室吉林长春

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 -331.27 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 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

Morphological and Structural Studies of sPS/aPS Blends

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chinese Chemical Letters 1998年第4期9卷 407-410页

作者： Sheng Qing XU Bin CHEN Yang LIU He Sheng CHEN bao tong huang(changchun institute of applied chemistry, chinese academy of sciences, changchun 130022) changchun Inst. of applied chemistry Chinese Academy of Sciences Changchun 130022 China

The morphology and structure of the syndiotactic polystyrene (sPS)/atactic polystyrene (aPS) blends with various compositions have been studied by means of DSC, optical microscopy, SAXS, and WAXD. The results show that aPS is miscible with amorphous region of sPS. There is no macroscopic evidence that aPS forms separated domains in the blends. The decrease in crystallinity of sPS in the blends implies segregation of the aPS to the interfibrillar regions of the spherulites of sPS. The constancy of interlamellar distance and melting points indicates that the fibrillar structural units of sPS is unchanged on addition of aPS to sPS, and the unchanging parameters of the sPS unit cells mean that aPS does not enter the unit cells of sPS.

关键词： blend syndiotactic polystyrene compatibility structure

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 applied chemistry, chinese academy of sciences, changchun, Jilin 130022, 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.

The Influence of Bond Valence on Bond Covalency in RMn_2O_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 chemistry, chinese academy of sciences, changchun 130022) changchun Inst. of applied chemistry Chinese Academy of Sciences Changchun 130022 China

The relationship between bond valence and bond covalency in RMn2O5 (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_2O_5

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 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

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

PREPARATION OF Pb-Ca-Na MASTER ALLOY USING MOLTEN CHLORIDE SALT ELECTROLYSIS

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中国有色金属学会会刊：英文版 1996年第2期6卷 18-19,21+25页

作者： Song Renying Wang Xingjie Luo Shumei Jiang Chan Tang Dingxiang(changchun institute of applied chemistry ,chinese academy of sciences, changchun 130022) changchun institute of applied chemistry Chinese Academy of Sciences Changchun 130022 China

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关键词： Pb-Ca-Na master alloy molten chloride salt electrolysis preparation

Copolymerization of N-4-Dibenzoylmethane Maleimide with Styrene

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chinese Chemical Letters 1999年第9期10卷 787-788页

作者： Qing Hui CHU Meng Xian DING(changchun institute of applied chemistry. chinese academy of sciences.changchun 130022) changchun institute of applied chemistry Chinese Academy of Sciences

The copolymer of N-4-dibenzoylmethane maleimide (p-DBMI) with styrene (St) was prepared and characterized by gel permeation chromatography, thermal analysis and spectroscopy.

关键词： N-4-dibenzoylmethane maleimide styrene copolymer

THE　RELATION　BETWEEN　MOLECULAR　MOTION　AND　ION　CONDUCTIVITY　ON　A　NEW　COMBLIKE　POLYMER

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chinese Chemical Letters 1996年第7期7卷 653-656页

作者： Li QI Yun Qing LIN Fo Song WANG(changchun institute of applied chemistry, chinese academy of sciences,changchun 130022) changchun Inst. of applied chemistry Chinese Academy of Sciences Changchun 130022

A new amorphous comblike polymer(CBP) based on methylvinyl ether/maleic anhydride alternating copolymer backbone and on oligooxyethylene side chain was synthesized The dynamicmechanical properties of CBP-Li salt complexes showed that there were two glass *** are two peaks in the plot of the ionic conductivity *** salt concentration. The plot ofLog σagainst 1/(T-To) shows an unusual dual VTF behavior when using side chain glasstransition temperature (Tβ) as To.

关键词： RELATION THE MOLECULAR AND BETWEEN