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1.
张天谊  朱世民 《分析化学》1995,23(10):1185-1188
用循环伏安法研究了2-氨基-9,10-蒽醌及其衍生物在DMF-0.1mol/LTBAP溶液中的电化学行为,结果表明它们在铂电极上均发生两步连续的单电子还原过程,取代基R及水和苯甲酸等质子性试剂的加对伏安曲线有很大的影响。  相似文献   

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Thin polymer films were obtained from 3-methoxythiophene at the cathode in a dc discharge. It was found using Fourier transform IR spectroscopy that thiophene rings were the main structural units of the polymer; aliphatic fragments and oxygen-containing groups were also present. The polymer based on 3-methoxythiophene was found to exhibit p-type intrinsic conduction with an activation energy of 0.045 eV. The conductivity of the polymer at 20°C was 10−8 Ω−1 cm−1, and doping with iodine resulted in a rise in conductivity to 10−3 Ω−1 cm−1.__________Translated from Khimiya Vysokikh Energii, Vol. 39, No. 5, 2005, pp. 382–385.Original Russian Text Copyright © 2005 by Drachev, Gil’man, Krasovskii, Costa-Belobrzeckaja.  相似文献   

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戴李宗  傅暄 《应用化学》1999,16(2):14-17
以阴离子聚合法合成的窄分布聚苯乙烯(NDPS)进行氯甲基化后,再与由基团转移聚合法合成的活性聚甲基丙烯酸甲酯(PMMA)进行大分子反应,得到了主链为聚苯乙烯,支链为聚甲基丙烯酸甲酯的接枝共聚物(PStgPMMA);探讨了聚合物的合成条件,GPC测试结果表明,得到的接枝共聚物的分子量和设计分子量相近且主链和支链分子量均可较好的控制.利用扫描电镜、核磁和红外技术对PStgPMMA的形态、结构进行了表征.  相似文献   

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Abstract

Nine members of the octa-n-alkanoyloxy-9,10-anthraquinone series, ranging from octanoyloxy (n = 8) to hexadecanoyloxy (n = 16) (where n is the number of carbon atoms per chain), were prepared and their mesomorphic properties studied by differential scanning calorimetry and optical microscopy. All the compounds studied are mesomorphic with the higher homologues exhibiting two (for n ≧ 12) or even three (for n ≧ 14) columnar mesophases. For n = 8 to 11, the phase sequence is C-DB-I, where DB is an optically biaxial mesophase with a two-dimensional pgg symmetry. For n = 12, 13, the phase sequence is C-M3-DB-I, where M3 is a highly ordered phase whose structure has not been identified. Finally for n = 14 to 16, the phase sequence is C-M3-DB-DA-I, where DA is an hexagonal phase. In all cases, the phases change from high to low order with increasing temperature and all transitions are first order. Compared with the corresponding hexa-substituted naphthoquinones the present series generates larger mesomorphic ranges and the higher homologues exhibit a uniaxial phase which is lacking in the hexa-substituted series. The increase in volume occupied by the aliphatic chains in the octa-substituted series is evidently sufficient to reduce the interaction between the aromatic cores of the different columns to permit the stability of a uniaxial phase.  相似文献   

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Emission and excitation spectra of 9,10-anthraquinone in the vapor phase have been measured and compared with those in the condensed phases. It is shown that the emission of 9,10-anthraquinone vapor consists of the S1 (n,π*) → S0 fluorescence and T1 (n,π*) → S0 phosphorescence, with the origins at 23 700 and 22 030 cm−1, respectively. The present study presents new measurements that substantially clarify the emission behavior of this molecule in the vapor phase.  相似文献   

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Nine members of the octa-n-alkanoyloxy-9,10-anthraquinone series, ranging from octanoyloxy (n = 8) to hexadecanoyloxy (n = 16) (where n is the number of carbon atoms per chain), were prepared and their mesomorphic properties studied by differential scanning calorimetry and optical microscopy. All the compounds studied are mesomorphic with the higher homologues exhibiting two (for n ≧ 12) or even three (for n ≧ 14) columnar mesophases. For n = 8 to 11, the phase sequence is C-DB-I, where DB is an optically biaxial mesophase with a two-dimensional pgg symmetry. For n = 12, 13, the phase sequence is C-M3-DB-I, where M3 is a highly ordered phase whose structure has not been identified. Finally for n = 14 to 16, the phase sequence is C-M3-DB-DA-I, where DA is an hexagonal phase. In all cases, the phases change from high to low order with increasing temperature and all transitions are first order. Compared with the corresponding hexa-substituted naphthoquinones the present series generates larger mesomorphic ranges and the higher homologues exhibit a uniaxial phase which is lacking in the hexa-substituted series. The increase in volume occupied by the aliphatic chains in the octa-substituted series is evidently sufficient to reduce the interaction between the aromatic cores of the different columns to permit the stability of a uniaxial phase.  相似文献   

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借助引发剂过硫酸钾(KPS),采用原位聚合法将苯乙烯(St)与Gemini型阳离子分子顺丁烯二酸二乙酯撑基双[辛烷基二甲基氯/溴化铵](G8-2-8)在季铵化壳聚糖(QCS)的醋酸溶液中,引发聚合形成不同嵌段比例(St与G8-2-8的摩尔比)的嵌段聚合物。 然后利用戊二醛(GA)为交联剂将QCS交联形成网状结构,将上述线性嵌段聚合物“锁定”在交联的QCS网状结构中,制备了一系列具有半互穿网络结构(Semi-IPN)的阴离子导电膜。 性能测试的结果表明,该系列膜具有较高的机械性能和电导率。 当G8-2-8含量为QCS质量的20%,嵌段比例为5:1时,表现出最高的离子交换量(1.35 mmol/g),断裂伸长率(26.47%)和电导率(70 ℃,6.97×10-2 S/cm)。 热稳定性测定结果表明,该膜具有良好的热稳定性能,最低分解温度高于210 ℃。  相似文献   

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High Energy Chemistry - The modification of polyvinyltrimethylsilane under treatment by direct-current discharge at a reduced pressure has been investigated. Polymer films were placed at the anode...  相似文献   

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Hu HY  Xiang JF  Cao J  Chen CF 《Organic letters》2008,10(21):5035-5038
The first selective catalytic hydrogenation induced by the artificial helix based on oligo(phenanthroline dicarboxamide)s containing a 9,10-anthraquinone subunit is described. Due to the steric hindrance within the helically folded oligomers, the selective reductions of the anthraquinone units were completely different from those of model substrates, which subsequently mimicked the enzyme catalysis for preventing some reactions from occurring.  相似文献   

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For the molecule of 9,10-anthraquinone, vibration frequencies and intensities have been calculated, and a theoretical spectral curve has been plotted, giving an adequate reflection of experimental manifestations over a broad spectral interval. This study made it possible to obtain a correct system of parameters for a model of the 9,10-anthraquinone molecule. Theoretical analysis has provided a basis for distinguishing vibration frequencies, active in the spectrum, that are characteristic with respect to frequency and intensity.K. A. Timiryazev Agricultural Academy. Scientific-Research Institute of Physical Problems. Translated from Zhurnal Strukturnoi Khimii, Vol. 34, No. 1, pp. 169–178, January–February, 1993.  相似文献   

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Conclusions The photochemical reaction of 9,10-anthraquinone with chloroform and toluene respectively gives 9-hydroxy-9-trichloromethyl-10-anthrone and 9-hydroxy-9-benzyl-10-anthrone.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 5, pp. 1142–1143, May, 1981.  相似文献   

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1-Hydroxyanthraquinone and its substituted derivatives exist as equilibrium mixtures of four tautomers and rotational isomers. Their anions have 9,10-and 1,10-quinoid structures. Each tautomer or conformer is characterized by a single π1,π* band in the electronic absorption spectrum.  相似文献   

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