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61.
Fernando R. Díaz Jorge L. Torres M. Angélica Del Valle Jorge H. Vélez J. Christian BernÈde Gastón A. East 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(10):1101-1108
Poly(3,5‐dichloroaniline) was prepared by chemical oxidation in the presence of various sulfonic acids as doping agent, using potassium permanganate as oxidant. 1‐Naphtalene sulfonic acid, 2‐naphatalene sulphonic acid, 1,5‐naphtalene disulfonic acid, and p‐toluenesulfonic acid were the acids of choice. Infrared and UV‐Vis spectroscopy, utilized to characterize the polymers, revealed that the compounds exist in the emeraldine (conductive) oxidation state. The level of doping, conductivity, and morphology were determined as well. The presence of a sulfonic acid produces a morphological change, from granular to microtubule structures, which is responsible for the strong increase in the conductivity of the polymer. 相似文献
62.
Zheng Li Jin-Lan Yu Sheng-Yi Shi Wei Zhu 《Phosphorus, sulfur, and silicon and the related elements》2013,188(5):1031-1037
A rapid method to N-acyl ureas from corresponding N-acyl thioureas is described. N-coumaroyl-N′-arylthioureas, which are easily prepared by the reaction of coumarin-3-carboxylic acid chloride with potassium thiocyanate and arylamines, can be expeditiously transformed into corresponding N-acyl ureas via r.t. grinding with wet silica supported potassium permanganate under solvent-free conditions in an excellent yield. 相似文献
63.
64.
将介孔分子筛MCM-41依次与3-氯丙基三乙氧基硅烷、二氨基硫脲和水杨醛反应,得到席夫碱修饰的介孔分子筛MCM-41催化剂,以过氧化氢为氧源,研究了其与K2CO3共同催化α,β-不饱和酮的环氧化反应。 化合物的结构经1H NMR和IR分析确认。 考察了金属盐、溶剂、催化剂用量、反应时间等因素对环氧化反应的影响。 结果表明,室温下α,β-不饱和酮的环氧化反应在短时间内均以较高的产率(最高达93%)得到了相应的产物。 同时,对催化剂的重复利用进行了研究,发现重复使用4次,仍能以较高产率得到环氧化产物。 相似文献
65.
Palladium supported on carbon (Pd/C) has been shown to be an effective catalyst for the cross-coupling of potassium p-tolyltrifluoroborate with a variety of aryl bromides and iodides. Yields ranging from moderate to good were obtained using Pd/C in ethanol/water mixtures with potassium carbonate as base at 50 °C under an air atmosphere. 相似文献
66.
67.
Nikos Ekizoglou Nikos Hadjichristidis 《Journal of polymer science. Part A, Polymer chemistry》2002,40(13):2166-2170
Multiblock copolymers of ethylene oxide, with four and five different blocks, were synthesized by the sequential anionic polymerization of styrene, isoprene, 2-vinyl pyridine, t-butyl methacrylate, and ethylene oxide with benzyl potassium as an initiator. The monomer sequence was based on the relative nucleophilicity of the active centers. Characterization of the multiblock copolymers by size exclusion chromatography (with refractive-index and UV detectors), membrane osmometry, and NMR spectroscopy confirmed that benzyl potassium is an efficient initiator for the synthesis of well-defined multiblock multicomponent copolymers of ethylene oxide. © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 40: 2166–2170, 2002 相似文献
68.
Kh. M. Minachev T. S. Starostina V. V. Kharlamov J. Komorek T. Romotowski 《Russian Chemical Bulletin》1993,42(10):1643-1648
The interactions between C3H6, AcOH and O2 were investigated on 1.5 % Pd/TsVM catalysts prepared with and without addition of 15 % AcOK. Three states for surface oxygen
on the promoted catalyst were distinguished. Two of them are involved in the oxidation of AcOH and C3H6 to CO2 and H2O, whereas the adsorbed species of the third type participates in the formation of allyl acetate. The O/Pd ratios for the
promoted catalyst fall in the range from 3 to 4, the nonpromoted system is characterized by an O/Pd value of 0.5. IR-spectral
data are used to discuss the reaction scheme for the formation of allyl acetate.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 1721–1726, October, 1993. 相似文献
69.
V. L. Shirokii V. A. Knizhnikov T. P. Konovalov Z. P. Zubreichuk A. A. Erdman S. E. Nefedov I. L. Eremenko A. I. Yanovskii Yu. T. Struchkov N. A. Mayer 《Russian Chemical Bulletin》1993,42(4):732-733
Co-electrolysis of potassium 1,2-dicarbadodecahydroundecaborate and indene in 0.1N sodium bromide solution in dimethylsulfoxide using iron electrodes afforded -indenyl--(3)-1,2-dicarbollyliron(III).Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 4, pp. 764–765, April, 1993. 相似文献
70.
The thermal decarboxylation of three dicarboxylic perfluoropolyether potassium salts of relatively short chain length has been investigated and the products and kinetics of the main reactions have been defined. From the rate constants and Arrhenius parameters data, the second decarboxylation appears to be quantitatively rather close to the first. 相似文献