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981.
Yan Ji Haijun Niu Haiyang Zhang Wenjun Wu Jiwei Cai Cheng Wang Xuduo Bai Wen Wang 《Journal of Solid State Electrochemistry》2014,18(6):1537-1544
The bismaleimide (BMI) monomer containing triphenylamine was prepared firstly. Then BMI was reacted with different diamines by Michael addition to obtain prepolymers, respectively. Finally, polyimides (PIs) were obtained through melting procedure. The effects of the structure of BMI moiety and thermal curing condition on thermal stability of PIs were studied by thermogravimetric analysis. PIs have excellent processing properties for film casting. Cyclic voltammetry of PI films was carried out on an indium-doped tin oxide-coated glass substrate. Results which exhibit two reversible oxidations at 0.71–0.78 and 1.06–1.16 V vs Ag/AgCl. The electrochromic performance was investigated by spectroelectrochemical methods. These anodically coloring polymer films not only showed good electrochromic properties but also exhibited high optical contrast ratio of transmittance with a color changing from yellow to green. After 100 cyclic switches, the polymer films still retained excellent redox and electrochromic activity. 相似文献
982.
Bing‐Jie Zhang Ju‐Ming Yan Zi‐Kun Wu Ya‐Ping Liu Mei‐Fen Bao Gui‐Guang Cheng Xiao‐Dong Luo Xiang‐Hai Cai Yan Li 《Helvetica chimica acta》2013,96(12):2288-2298
Ten new monoterpenoid indole alkaloids, ochroborines A and B ( 1 and 2 , resp.), 10‐hydroxyisovallesiachotamine ( 3 ), 10‐hydroxyisositsirikine ( 4 ), 10,11‐dimethoxysitsirikine ( 5 ), 10‐methoxyapoyohimbine ( 6 ), 10‐hydroxyakuammidine ( 7 ), akuammidine 17‐O‐β‐D ‐glucoside ( 8 ), 15α‐hydroxyapparicine ( 9 ), and 15α‐hydroxy‐10‐methoxyapparicine ( 10 ), and 24 known alkaloids were isolated from leaves and twigs of Ochrosia borbonica J. F.Gmel . These structures were elucidated based on 1D‐ and 2D‐NMR, FT‐IR, UV, and MS data. 10‐Hydroxyisovallesiachotamine ( 3 ), ellipticine, and 10‐methoxyellipticine showed cytotoxic activities against five human cancer cell lines. 相似文献
983.
Gui Rong QU Ming Wei GENG Su Hui HAN Zhi Guang ZHANG Feng XUE 《中国化学快报》2006,17(9):1149-1151
Nucleoside analogues generally possess outstanding biological activity, mainly as antitumor and antiviral agents. Many works have been done for the synthesis of natural nucleosides and their analogues1-5. N6-(2-Hydroxyethyl)adenosine (HEA), which behaves … 相似文献
984.
985.
In the study of cyclohexane monoxygenation with PhIO catalyzed by TPPFe( Ⅲ )X, we found the Influence of different axial ionic ligands X (X = F, Cl, Br, I, SCN, OR, R, CH,3, C2H6, (CH3)2CH, (CH2)3C)in TPPFe( Ⅲ )X on the oxidation products distribution and the yields of cyclohexanol. This paper deals with the linear relationship between the catalytic activity of TPPFe(Ⅲ)X and both the electronic or/ and steric effects of the axial ligands OR in TPPFe(Ⅲ)OR on its catalytic activity. 相似文献
986.
Synthesis and Nonlinear Optical Property of a Polyphosphazene with High Glass Transition Temperature
ZhenLI JinGuiQIN ZhouYANG ChengYE 《中国化学快报》2004,15(4):489-491
A new polyphosphazene containing binaphtholyl and indole azo chromophores as side chains with high glass transition temperature(Tg) was synthesized by a post-functional method.The polymer was well characterized.Its Tg was tested to be 168 ℃,and the poled film of P2 reveals a resonant d33 value of 20 pm/V by second harmonic generation(SHG) measurements. 相似文献
987.
用高速纹影诊断技术研究激光辐照下金属表面发生汽化的特征及蒸气发展运动过程,结合汽化模型给出了凝聚相表面温度与激光入射功率密度的关系。由实验得到了不同入射激光功率密度下汽化表面(凝聚相)温度,蒸气羽阵面速度,前驱空气冲击波速度。 相似文献
988.
A new series of azobenzene dyes, which possessed colorimetric and ratiometric recognition to Hg2+ based on the mechanism of internal charge transfer (ICT), was developed and characterized. The molecules involving azo and imino functional groups can coordinate with Hg2+ to result in a large blue shift from 453 to 363 nm corresponding to a notable color change from orange to pale yellow in aqueous methanol solution (H2O/CH3OH=1/4, V/V), which can be applied to naked eye detection of Hg2+. The sensitivity, selectivity and binding mode of the sensors to Hg2+ were investigated by UV‐Vis spectroscopy. 相似文献
989.
990.
InourpreviousworkwehavereportedthestudiesonthereactionofvinyItriazolcderivativeswithhydroxylamine,andfOundthatcycloadditiontookp1aceandthenewheterocycliccompoundsl,2-oxazocyclopentaneshavingplant-growthregulatingactivitywereobtainedl,2.InordertosynthesizenewheterocycliccompoundsandtosearchfOrnewcompoundshavingbioactivity,thereactionofa-triazolyl-a,ll-unsaturatedketones(Z)-or(E)-4,4-dimethyl-1-aryl-2-(l,2,4-triazol-l-yl)-l-penten-3-onesI.-bwithphenylhydrazinewasstudied.Theresultshowedthatcycl… 相似文献