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CHEMICAL STRUCTURE DEPENDENCE OF THE INTERNAL ENERGY CONTRIBUTION IN RUBBER ELASTICITY

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chinese Journal of Polymer Science 2001年第5期19卷 447-449页

作者： Juan Sun Xiao-zhen Yang Polymer Physics laboratory Center for molecular sciences, {3. chinese academy of sciences Beijing 100080 china chinese Acad Sci Polymer Phys Lab Ctr Mol Sci Inst Chem Beijing 100080 Peoples R China

Conformational elasticity theory recently developed has been used to explore the internal energy contribution to the elastic force f(e)/f as a function of strain for poly(cis-1,4-isoprene) and poly(trans-1,4-isoprene). Calculated f(e)/f values are in good agreement with those obtained experimentally. Results show that behavior of f(e)/f is mainly contributed by chemical structure, or intramolecular interaction, supporting the experimental observations, and that the internal energy contribution is strain dependent.

关键词： conformational elasticity theory internal energy contribution poly(cis-1,4-isoprene) poly(trans-1,4-isoprene)

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,{3.,Beijing 100080,china 2. institute of chemistry,{3.,Beijing 100080,china 3. Graduate University of {3.,Beijing 100049,china national Key laboratory of Acoustics Institute of Acoustics Chinese Academy of Sciences Beijing 100080 China institute of chemistry Chinese Academy of Sciences Beijing 100080 China Graduate University of chinese academy of sciences Beijing 100049 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.

PREPARATION AND PROPERTIES OF ETHYL-CYANOETHYL CELLULOSE/POLYACRYLIC ACID COMPOSITE FILMS WITH REFLECTION COLORS

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chinese Journal of Polymer Science 2001年第3期19卷 277-282页

作者： Yong Huang institute of chemistry, chinese academy of sciences, Beijing 100080 {3. laboratory of Cellulose and Lignocellulosics chemistry Guangzhou institute of chemistry chinese academy of sciences, Guangzhou 510650, {3. 中科院化学所北京

Ethyl-cyanoethyl cellulose [(E-CE)C]/acrylic acid (AA) becomes a cholesteric liquid crystalline solution withvivid colors when the (E-CE)C concentration is 42 wt%～52 wt%. (E-CE)C/polyacrylic acid (PAA) composites withcholesteric structure were prepared by polymerzing AA in (E-CE)C/AA liquid crystalline solutions. The layers of orderedpolymer chains in the cholesteric phase were inclined during polymerization and the degree of the inclination depended onthe polymerization temperature and the concentration of the solution before polymerization. The cholesteric structure in thecomposites could not be changed when temperature was lower than 100℃. Cross-linking of the PAA in compositesimproved their water-resistance. The cholesteric order of the composites without cross-linking was destroyed when theywhere immersed in water. The color derived from the selective reflection of the cholesteric phase of the cross-linkedcomposites turned from blue to red after the composites absorbed water. The color of the composites could be returned to theoriginal one when the absorbed water was removed from the swollen composites.

关键词： Cholesteric structure Composites Selective reflection Liquid crystalline solutions

A Dye-sensitized Nanocrystalline Solid State Photovoltaic Cell

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chinese Chemical Letters 2000年第9期11卷 813-814页

作者： Dong She ZHANG Xu Rui XIAO laboratory of photochemistry, Center for molecular {3., institute of chemistry, chinese academy of sciences, Beijing, 100080 chinese Acad Sci Inst Chem Ctr Mol Sci Lab Photochem Beijing 100080 Peoples R China

A new type of dye-sensitized nanocrystalline solid state photovoltaic cell based on the wide band gap n-TiO2/p-CuI heterojunction was fabricated. Tetra-carboxyphenyl porphyrine (TPP-(COOH)(4)), squarylium cyanine derivative (SQ-(CH2),(SO3.y+)-Py-.) and ruthenium bipyridyl complex (RuL2(NCS)(2)) were used as photosensitizers. Larger photocurrents and photovoltages were shown in the cell sensitized by ruthenium bipyridyl complex and can be further increased by intercalation of a TiO2 thin underlayer.

关键词： nanocrystalline TiO2 electrode dye sensitization solid state cell

6-Membered ring intermediates in polymerization of N-carboxyanhydride-L-α-arginine in H_2O

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Science china chemistry 2009年第8期52卷 1220-1226页

作者： XIN Liang1,REN Jie1,XIANG JunFeng2,YAN Qin1,XIE Yi1,WANG KongJiang1,LAI PingAn3.& BAI YaDuo3.1 institute of Biophysics,chinese academy of sciences,Beijing 100101,china 2 Beijing {3. laboratory for molecular sciences(BNLMS),centre for molecular sciences,institute of chemistry,chinese academy of sciences,Beijing 100080,china 3.Beijing Entry-Exit Inspection and Quarantine,Beijing 100026,china 1. institute of Biophysics Chinese Academy of Sciences Beijing 100101 China 2. Beijing national laboratory for molecular {3. (BNLMS) Centre for Molecular Sciences Institute of Chemistry Chinese Academy of Sciences Beijing 100080 China 3. Beijing Entry-Exit Inspection and Quarantine Beijing 100026 China

In polymerization of N-carboxyanhydride-L-α-arginine(L-Arg-NCA) in H2O,nucleophilic reaction of guanidine group with the carbonyl group of L-Arg-NCA leads to quick intramolecular rearrangement,yielding a 6-membered ring intermediate 1-amidino-3.amino-2-piperidone,which is either elongated by another L-Arg-NCA yielding arginyl-1-amidino-3.amino-2-piperidone or hydrolyzed to L-α-*** oligoarginines are formed mainly through hydrolysis of *** is a unique pathway in polymerization of L-Arg-NCA with regard to the usual pathway of elongations by reaction of N-carboxyanhydride-L-α-amino acid with L-α-amino acid or oligopeptides.

关键词： N-carboxyanhydride L-Arg-NCA intermediates L-α-arginine polymerization

High-resolution photofragment translational spectro- scopy for the UV photodissociation of C_2H_5I

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Science china chemistry 2007年第4期50卷 476-482页

作者： BI WeiBin, XU XiLing, HUANG JianGou, XIAO DaoQing & ZHU QiHe Beijing national laboratory for molecular {3., State Key laboratory of molecular Reaction Dynamics, institute of chemistry, chinese academy of sciences, Beijing 100080, china 1. Beijing national laboratory for molecular {3. State Key Laboratory of Molecular Reaction Dynamics Institute of Chemistry Chinese Academy of Sciences Beijing 100080 China

The photodissociation of ethyl iodide at 279.71, 281.73. 3.4.02 and 3.4.67 nm has been studied on our new mini-photofragment translational spectrometer with a total flight path of only 5 cm. Some vibra-tional peaks are firstly resolved in the TOF spectra of I*(2P1/2) and I(2P3.2) channels. These vibrational peaks are assigned to the excitation states (ν2 = 0, 1, 2,…) of the umbrella mode (ν2, 540 cm-1) of the photofragment C2H5, and the distribution of the vibrational states is obtained. The dissociation energy has been determined to be D0(C-I)=2.3.4 ± 0.03.eV. The energy partitioning of the available energy (Eavl=ET+Eint=ET+EV,R) calculated from our experimental data E int /E avl= 22.1% at 281.73.nm, 22.4% at 3.4.02 nm for the I* channel, and E int /E avl= 25.2% at 279.71 nm, 25.9% at 3.4.67 nm for the I channel, seem to be more reliable.

关键词： photofragment translational spectroscopy C_2H_5I photodissociation vibrational state distribution energy partitioning dissociation energy

The design and synthesis of fused thiophenes and their applications in organic field-effect transistors

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Science china chemistry 2010年第4期53卷 779-791页

作者： LIU Ying, YU Gui & LIU YunQi Beijing national laboratory for molecular {3., Key laboratory of Organic Solids, institute of chemistry, chinese academy of sciences, Beijing 100190, china 1. Beijing national laboratory for molecular {3. Key Laboratory of Organic Solids Institute of Chemistry Chinese Academy of Sciences Beijing 100190 China

Fused thiophenes refer to oligothienoacenes in which several thiophenes are coupled together via twoor multi-positions and their derivatives. The synthesized organic semiconductors based on fused thiophenes exhibit excellent field effect properties due to their efficient intermolecular S…S interactions and π…π stacking. The performances of organic field-effect transistors (OFETs) depend not only on the materials but also on the devices. Such factors which influence the device performances as device structures, fabrication technologies and interface engineering are extensively investigated based on the fused thiophenes. Searching for new organic semiconductors and improving the device fabrication technologies are two major issues in the development of OFETs.

关键词： fused thiophenes oligothienoacenes organic field-effect transistors device performance

Discovery of immune related factors in Fenneropenaeus chinensis by annotation of ESTs

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Progress in Natural Science:Materials International 2004年第1期14卷 48-55页

作者： SHEN Yaoqing 1,2 , XIANG Jianhai 1*, WANG Bing 1,2 , LI Fuhua 1 and TONG Wei 3.1. Experimental Marine Biology laboratory, institute of Oceanology, chinese academy of sciences, Qingdao 266071,{3. 2. Graduate School of the chinese academy of sciences, Beijing 10003., {3. 3. Genomics & Bioinformatics institute, chinese academy of sciences, Beijing 1013.0, {3.) chinese Acad Sci Inst Oceanol Expt Marine Biol Lab Qingdao 266071 Peoples R China chinese Acad Sci Grad Sch Beijing 100039 Peoples R China chinese Acad Sci Geonom & Bioinformat Inst Beijing 101300 Peoples R China

A total of 10446 expressed sequence tags (ESTs) are obtained by a large scale sequencing of a cDNA library from cephalothorax of adult Fenneropenaeus chinensis . An EST analysis platform was built up based on local computers and bioinformatic techniques were used to annotate these ESTs in order to promptly find possible functional genes, especially for immune related factors. About 4% of the ESTs show similarity to the coding sequences of such factors, including lectin, serine protease, serpin, lysozyme, etc. These ESTs provide a partial profile of the immune system in F. chinensis and useful information for further study on these genes.

关键词： Fenneropenaeus chinensis bioinformatics ESTs immune factors

SYNTHESIS AND CHARACTERIZATION OF NEW STABILIZERS WITH OPTIMAL molecular WEIGHT

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chinese Journal of Polymer Science 2001年第4期19卷 341-350页

作者： Jiang-qing Pan institute of chemistry chinese academy of sciences, Beijing 100080 {3. chinese Acad Sci Inst Chem Beijing 100080 Peoples R China

Over 2 x 10(8) tons of polymers are produced every year, and a large portion of polymers faces the degradation problem. There are many effective methods to protect polymers against degradation and the addition of stabilizers to polymer remains the most convenient and effective way of enhancing polymer life and performance. In this article, a series of effective stabilizers with optimal molecular weight (MW), including common, monomeric and polymeric stabilizers (antioxidant and light stabilizer) were synthesized using isocyanation, controlled isocyanation, hydrosilylation, epoxide addition, macroreaction of stabilizing functional compounds and polymerization of monomeric stabilizers. The structure and performance of these new stabilizers were characterized by using IR, NMR, MS, UV-spectra, XPS and elemental analysis. The current development of stabilizer synthesis was also reviewed.

关键词： preparation of stabilizer antioxidant hindered amine light stabilizer isocyanation hydrosilylation