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Recovery of Uniaxially Stretched Amorphous Poly(ethylene terephthalate) Film

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Chinese Chemical Letters 1998年第10期9卷 965-966页

作者： Nan Jian SUN and De Yan SHEN(Polymer physics Laboratory, institute of chemistry,Chinese Academy of Sciences, Beding, 100080.) Chinese Acad Sci Inst Chem Polymer Phys Lab Beijing 100080 Peoples R China

Recovery behavior of uniaxially stretched amorphous poly(ethylene terephthalate) (a-PET) film near glass transition temperature (T-g) was studied. A strain recovery curve showed that the recovery was made up of two co... 详细信息

关键词： polyethylene terephthalate uniaxial stretching relaxation recovery

Luminescence of Unusual Bismuth in Barium Borates (BaB_8O_13:Bi)

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Journal of Materials Science & Technology 1999年第3期15卷 281-282页

作者： Qinghua ZENG Tianzhi ZHANG Zhiwu PEI and Qiang SU(Laboratory of Rare Earth chemistry and physics, Changchun institute of Applied chemistry, Chinese Academy of Sciences, Changchun 130022, China) Laboratory of Rare Earth chemistry and physics Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun 130022 China

The luminescence of unusual divalent bismuth (Bi2+) in BaB8O13 is reported. The emission band with maximum peak at 592 nm corresponds to the 2P3/2→2P1/2 transition of Bi2+ in the matrix and the excitation spectrum with two bands peaked at 470 and 580 nm respectively corresponds to two split crystal-field levels of 2P3/2 state. The small Stokes shift (~350 cm-1) reflects the rigid structure of the host for the Bi2+ ions

关键词： BaB8O13

On the parameterization scheme of gravity wave drag effect on the mean zonal flow of mesosphere

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Chinese Science Bulletin 2003年第10期48卷 1020-1023页

作者： GAO Shouting & RAN Lingkun State Key Laboratory of Atmosphere physics and chemistry (LAPC), institute of Atmospheric physics, Chinese Academy of Sciences, Beijing 100029, China State Key Laboratory of Atmosphere physics and chemistry (LAPC) Institute of Atmospheric Physics Chinese Academy of Sciences China

Based on McFarlane抯 parameterization scheme of gravity wave drag, a refined gravity-wave-drag scheme is presented. Both the drag effect of the momentum flux and the dissipation effect of gravity wave breaking on the mean zonal flow are included in the refined parameterization scheme. The dissipation effect can be formulated with the gravity wave numbers and the mean quantities. The refined parameterization scheme may represent a complete drag effect of stationary gravity wave breaking on the mean zonal flow.

关键词：参数化法重力波阻纬向气流中间层大气动力学

Peculiar dynamical properties of plutonium hydrides

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Progress in Natural Science:Materials International 2006年第3期16卷 248-254页

作者： MENG Daqiao, ZHU Zhenghe, LUO Deli and JIANG Gang (institute of Atomic and Molecular physics, Sichuan University, Chengdu 610065, China National Key Laboratory of Surface physics and chemistry, Mianyang 621907, China) [a]institute of Atomic and Molecular physics Sichuan University Chengdu China [b]National Key Laboratory of Surface physics and chemistry Mianyang China

In the present work, the structure and spectra of PuH and PuH2 are defined by B3LYP/SDD method, from which the analytic potential energy function of PuH2 is derived. The analysis of quasi-classical molecular reaction dynamics is performed to study the state-state process of Pu(7Fg) + H2(X1∑g+). It is found that the reaction Pu(7Fg)+H2(X1∑g+)→PuH2(X7B1) has no threshold. The simultaneous hydrogenation process of plutonium with the main product of PuH2 is theoretically proved for the first time.

关键词： hydrogenation reaction of plutonium molecular dynamics density functional theory.

DFT Thermodynamic Research of the Pyrolysis Mechanism of the Carbon Matrix PrecursorTol uene for Carbon Material

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Chemical Research in Chinese Universities 2001年第2期17卷 219-225页

作者： WANG Hui, YANG Hai-feng, RAN Xin-quan WEN Zheng-yi and SHI Qi-zhen (chemistry Department, Modern physics institute and, Key Laboratory of physics Inorganic chemistry of Shan-Xi Province, Northwest University, Xi’an 710069, P. R. China) NW Univ Xian Dept Chem Xian 710069 Peoples R China NW Univ Xian Inst Modern Phys Xian 710069 Peoples R China NW Univ Xian Key Lab Phys Inorgan Chem Shan Xi Province Xian 710069 Peoples R China

Based on the experiments, the standard enthalpy△H■of the possible pyrolysis reactions of the carbon matrix precursor toluene was investigated by means of DFT method UB3LYP/ 3-21G *(based on semi-empirical method UAM1 and ab initio method UHF/3-21G*). The com- putation results with UB3LYP/3-21G* coincide with the experimental values well. Then, the mechanism for all types of the pyrolysis reactions of toluene was studied by UB3LYP/3-21G * The geometries of the reactant and the product radicals were optimized, meanwhile, the standard thermodynamic parameters of the pyrolysis reaction at different temperatures (298, 773, 843, 963 and 1 073 K) were calculated. The thermodynamic computation result shows that when the pyrolysis temperature of toluene is lower than 963 K, the reaction path supported by thermody- namics is that the C-H bond of the methyl on the benzene ring breaks and bitoluene form, while the temperature increases (about 1 073 K), the thermodynamic calculation result turns to support the reaction path producing phenyl radicals and methyl radicals. This mechanism is in accord with the experiments.

关键词： Carbon/carbon composites Toluene Pyrolysis mechanism UB3LYP/3-21G

Polymerization of Bisphenol A Epoxy Resin with Polyethylene glycol

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Chinese Chemical Letters 1997年第8期8卷 725-728页

作者： Zhen Zhong YANG De Lu ZHAo Mao XU(Polymer physics Laboratory, institute of chemistry, The Chinese Academy of Sciences, Beijing 100080) CHINESE ACAD SCI INST CHEMPOLYMER PHYS LABBEIJING 100080PEOPLES R CHINA

The catalyst boron trifluoride etherate was used to catalyze the reaction of epoxy resin with polyethylene glycol (PEG), and the effect of the concentration of the catalyst on the reaction is studied. It is shown that there exist two competitive reactions : I, self polymerization of epoxy resin via chain growth and II, copolymerization of epoxy resin with PEG via step growth. At high concentration of the catalyst reaction I dominates and reaction II is negligible. On the contrary, at low concentration of the catalyst, reaction II dominates and block copolymers are formed In the intermediate case, the two reactions are comparable with the result that a gel structure is obtained.

关键词： PEG Polymerization of Bisphenol A Epoxy Resin with Polyethylene glycol

Investigation on oxidation states of rhenium in Re-HEDP

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Nuclear Science and Techniques 2003年第3期14卷 174-177页

作者： WANG Wen-Jin, LUO Shun-Zhong, QIAO Jian, LIU Guo-Ping, LIU Ye-Bing (institute of Nuclear physics and chemistry, China Academy of Engineering physics, Mianyang 621900) institute of Nuclear physics and chemistry China Academy of Engineering Physics Mianyang 621900

The oxidation states of rhenium in Re-HEDP (hydroxyethylidene diphosphonate) were measured bythe methods of extraction and potentiometric titration. The oxidation state of rhenium in Re-HEDP was mostly +4valence, and the Re(Ⅳ)-HEDP was oxidized to Re( Ⅴ)-HEDP when it was titrated by I3- at pH 2.0. In the reductionsystem of Vc+Sn2+ , ReO4- was only reduced by Sn2+, but Vc was oxidized earlier than Sn2+ when it was titrated by I3.

关键词：铼电势滴定氧化态化合价锡放射性同位素肿瘤治疗

XPS Study on Water-Soluble Polymer Surfactant Film

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Chinese Chemical Letters 1997年第12期8卷 0-0页

作者： Jian XU Liang He SHI Mei Ling YE (Polymer physics Laboratory, institute of chemistry, Chinese Academy of Sciences, Beijing 100080) Chinese Acad Sci Inst Chem Polymer Phys Lab Beijing 100080 Peoples R China

By means of changing the detection angle, the molecular conformation of a new type of polymer surfactant, acrylamide-poly(oxyethykene alkyl ether)acrylate-anionic monomer random copolymer, was studied by x-ray photoel... 详细信息

关键词： XPS Study on Water-Soluble Polymer Surfactant Film

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Luminescent properties of Eu and Tb in SrB_(6)O_(10) matrix

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Chinese Science Bulletin 1997年第5期42卷 388-390页

作者： GAO Yong, SHI Chunshan and LI DechengLaboratory of Rare Earth chemistry and physics, Changchun institute of Applied chemistry, Chinese Academy of Sciences. Changchun 130022, China Laboratory of Rare Earth chemistry and physics Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun China

MOST rare earth ions are inclined to exist in abnormal valency, and the properties of rare earth correspond to the valence state of rare earth closely Both europium and terbium have abnormal valence state. Eu3+ and Tb3+ ions are a couple of conjugate rare earth ions; they are both important activated ions. The present note reports the luminescent properties of SrB6O10 xEu, yTb phosphors which are synthesized in air atmosphere. Eu3+, Eu2+ and Tb3+ ions can coexist in SrB6O10: xEu, yTb phosphors, and the emission intensity of europium（Ⅱ） is increased if the concentration of terbium（Ⅲ） is increased in SrB6O10: 0.006Eu3+, yTb3+

关键词： valency conjugate rare earth rare earth spectra.