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1前言间二氟苯是许多种含氟医药和农药的关键中间体。例如它是合成2’,4’—二氟—4—羟基—[1,1’—二苯基—3—羧酸](商品名称:二氯苯水杨酸;Diflubenzuron)的主要原料,此药对关节炎有特效,具有良好的消炎镇痛作用,可用于术后止痛剂。间二氟苯也用于结构环上1位具有2,4—二氟苯基的氟喹诺酮系抗菌剂的合成中,例如:特马沙星(Temafcoxacin)、托磺沙星(Tosulfloxacin)等,此系列抗菌剂通常具有适度的脂溶性和水溶性以及优异的抗菌活性。在农药领域里,可以用间二氟苯合成含氟苯基杀虫剂苯甲酰脲型的Diflubenzuron,该杀… 相似文献
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分别以二茂二氯化钛(Cp2TiCl2)和二茂二氯化锫(Cp2ZrCl2)与钐茂金属催化剂复合组成催化体系,并以甲基铝氧烷为助催化剂,进行宽分子量分布聚乙烯合成研究。研究发现与使用Cp2TiCl2和二(甲基茂基)氯化钐复合体系相比,使用其与二(特丁基茂基)氯化钐[(t—BuCp)2SmCl]复合体系能得到具有较高粘均分子量的聚乙烯。同样,使用Cp2ZrCl2与(t—BuCp)2SmCl复合体系也能得到具有较高粘均分子量的聚乙烯。且使用含(t-BuCp)2SmCl复合体系得到分子量分布指数达3.5以上的聚乙烯。 相似文献
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分析了中国及其他国家废旧耐火材料利用的条件及发展趋势,其中包括废旧MgO—C砖、Al2O3-MgO—C砖及MgO—Cr2O3砖,以及Al2O3-SiC—C质浇注料二次利用方面的研究成果。二次利用的耐火材料甚至显示出比原始耐火材料具有更好的性能。还探讨了废旧耐火材料二次利用的前景。 相似文献
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前言4—氨基—2,6—二甲氧基嘧啶(4—amino—2,6—dimethoxypyrimidine)是一个药物中间体,可用于合成长效磺胺药:2,6—二甲氧基—4—(对氨基苯磺酰胺嘧啶。该药毒性很低,而对上呼吸道和尿道方面的感染特别有效,对肾脏的刺激极为轻微,在血液中的浓度可以维持较长的时 相似文献
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4,4‘—二氨基二苯醚合成新工艺 总被引:3,自引:0,他引:3
采用对硝基氯苯一种原料以亚硝酸钠为催化剂在二甲亚砜溶剂中于碱性条件下合成出了4,4’—二硝基二苯醚,由此制备了4,4’—二氨基二苯醚并对其进行了精制。 相似文献
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2,4—二氟苯甲醛的合成 总被引:2,自引:2,他引:0
以2,4—二硝基甲苯为原料,通过还原、改进的西曼反应氟化、侧链氯化、水解制得2,4—二氟苯甲醛,考察了每步反应条件对合成的影响,总收率达到了23.5%,产品纯度大于99%。 相似文献
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介绍了采用二硫化钠合成巯基乙酸的新方法。以硫化钠和硫磺为基本原料制备二硫化钠,二硫化钠与氯乙酸钠合成2,2′-二硫代双乙酸钠,再用硫氢化钠和亚硫酸钠还原,经酸化、萃取、蒸馏,得到巯基乙酸。探讨了反应物浓度、反应温度、反应时间及酸化用酸的种类对巯基乙酸产品的影响。得出了最佳工艺条件:n硫化钠∶n硫∶n氯乙酸=1.4∶1.68∶1(物质的量比);硫化钠溶液的质量分数15%;合成2,2′-二硫代双乙酸钠时的反应温度45℃,反应时间30min;采用盐酸酸化还原。在此条件下,产品收率可达92.6%。 相似文献
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Infrared study on methyl methacrylate-methacrylic acid copolymers and their sodium salts 总被引:1,自引:0,他引:1
E.S. RufinoE.E.C. Monteiro 《Polymer》2003,44(23):7189-7198
Near, mid and far infrared spectra have been recorded for methyl methacrylate-methacrylic acid copolymers and their sodium salts. Methyl methacrylate-methacrylic acid copolymers, with various methacrylic acid contents were prepared by free radical polymerization. The sodium salts of (methyl methacrylate-methacrylic acid) copolymers were prepared by reaction of methacrylic acid units with sodium hydroxide. The acid content in copolymers was estimated by calorimetry and by reactivity ratios of monomers. The results showed that sodium MMA-MAA copolymers prepared by neutralization form ionic clusters and retain in its backbone non-neutralized acid groups. The results showed the effect of composition on spectroscopic data. The absorption/retention of water was observed in the examined samples. 相似文献
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插层改性水滑石及其对聚丙烯力学和阻燃性的影响 总被引:1,自引:0,他引:1
通过离子交换法制备了十二烷基磺酸钠、酒石酸氢钠、衣康酸改性的水滑石和十二烷基磺酸钠/衣康酸、十二烷基磺酸钠/酒石酸氢钠协同改性的水滑石(LDHs),通过熔融插层法制备得到了LDHs/PP复合材料。采用红外光谱(FTIR)、X射线衍射(XRD)、热重分析(TGA)对水滑石的结构和性能进行了分析表征,研究了LDHs/PP复合材料的力学性能和阻燃性。结果表明:上述几种单一和复合有机酸及盐改性剂都能不同程度地扩大水滑石的层间距;采用酸/盐协同改性的水滑石不仅有机基团含量较高,而且层间距大,显著提高PP的弯曲强度和阻燃性,表明酸和盐复合改性水滑石有显著协同作用及改性水滑石与PP基体相容性好。 相似文献
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A. V. Prabhudesai C. V. Viswanathan 《European Journal of Lipid Science and Technology》1979,81(5):194-196
Long-chain alkyl esters of N-acyl monobasic amino acids were prepared by reacting N-acyl amino acids with long-chain alkyl methane sulfonates in the presence of sodium bicarbonate in dimethylformamide. The necessary N-acyl amino acids were prepared by reacting an amino acid with an active fatty acid ester of p-nitrophenol in ethanol containing sodium bicarbonate. Reaction between a fatty acid and p-nitrophenol in chloroform, in presence of thionyl chloride, yielded the active ester necessary for the N-acylation of an amino acid. 相似文献
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C. Torre-Abreu M.F. Ribeiro C. Henriques F.R. Ribeiro 《Applied catalysis. B, Environmental》1997,13(3-4):251-264
CuMOR catalysts with different Si/Al ratios and copper contents, prepared from the acid and sodium forms, were studied in NO reduction with propene in the presence of excess oxygen. It was observed that the influence of zeolite Si/Al ratio on CuMOR catalytic activity for NO SCR by propene depends on the catalyst copper content, the reverse being also true. For mordenites prepared from the acid form, it was shown that the most active catalyst must have 60% of copper exchange, whereas for those prepared from the sodium form, the maximum catalytic activity is obtained for catalysts with 20% of copper exchange. Moreover, it was observed that at low copper-exchange levels, the catalyst prepared from the sodium form exhibits much higher activity than those prepared from the acid form. Although, when the copper-exchange level increases, the effect of zeolite form is less pronounced. Thus, it was indicated that Brönsted acidity does not promote the NO selective reduction by propene. 相似文献
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