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对国际上几家主要聚;甲醛生产公司所获得聚甲醛阻燃方面的专利进行了分类事理并进行了聚甲醛阻燃机理的探讨及部分聚甲醛阻燃剂合成方法的介绍。 相似文献
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介绍了日本旭化成公司的聚甲醛制造技术:①用甲醛缩二甲醇生产高浓度甲醛;②均聚甲醛的先进工艺;③共聚甲醛的工业化;④高润滑性能的嵌段共聚甲醛的制造。 相似文献
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Lipophilic 2′‐O‐Acetal Ester RNAs: Synthesis,Thermal Duplex Stability,Nuclease Resistance,Cellular Uptake,and siRNA Activity after Spontaneous Naked Delivery
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Dr. Annabelle Biscans Dr. Jean‐Rémi Bertrand Josephine Dubois Jacqueline Rüger Dr. Jean‐Jacques Vasseur Prof. Georg Sczakiel Dr. Christelle Dupouy Dr. Françoise Debart 《Chembiochem : a European journal of chemical biology》2016,17(21):2054-2062
The in vivo application of siRNA depends on its cellular uptake and intracellular release, and this is an unsatisfactorily resolved technical hurdle in medicinal applications. Promising concepts directed towards providing efficient cellular and intracellular delivery include lipophilic chemical modification of siRNA. Here we describe chemistry for the production of modified siRNAs designed to display improved transmembrane transport into human cells while preserving the potency of the RNAi‐based inhibitors. We report the synthesis and the biochemical and biophysical characteristics of 2′‐O‐phenylisobutyryloxymethyl (PiBuOM)‐modified siRNAs and their impact on biological activity. In the case of spontaneous cellular uptake of naked PiBuOM‐modified siRNA, we observed increased target suppression in human cells relative to unmodified or pivaloyloxymethyl (PivOM)‐modified siRNA. We provide evidence of improved spontaneous cellular uptake of naked PiBuOM‐modified siRNA and of substantial target suppression in human cells in serum‐containing medium. 相似文献
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甘油环缩甲醛丙烯酸酯的合成与应用 总被引:4,自引:1,他引:3
合成了甘油环缩甲醛丙烯酸酯,并用IR、H-NMR检测其结构,它含有加聚必不可少的双键,可作为UPR的活性稀释剂和交联剂,并赋予树脂空干性。 相似文献
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以氨基磺酸为催化剂,对以异丁醛和1,2-丙二醇为原料合成异丁醛1,2-丙二醇缩醛进行了研究。较系统地研究了醛醇摩尔比,催化剂用量,反应时间,带水剂诸因素对收率的影响,结果表明:氨基磺酸是合成异丁醛1,2-丙二醇缩醛的良好催化剂,最佳反应条件为:异丁醛为0.2-ml,n(异丁醛):n(1,2-丙二醇)=1:1.5,催化剂用量为反应物总质量的6.8%,带水剂环己烷15ml,反应时间60min。上述条件下,异丁醛1,2-丙二醇缩醛的收率可达71.15%。 相似文献
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Ion Agirre María Belén Güemez Anatolie Motelica Henk M. van Veen Jaap F. Vente Pedro L. Arias 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2012,87(7):943-954
BACKGROUND: Acetals can be considered important bio‐based diesel additives. The production of most of these compounds, from an alcohol and an aldehyde, suffers from low conversion due to thermodynamic limitations. These limitations can be overcome through the removal of the by‐product water. Previous studies showed that the in situ dehydration options of reactive distillation and pervaporation membrane reactor integration offer little advantage or at least not at reasonable unit dimensions. The aim of the present work is the development of a membrane based process and comparison with other alternatives (based on experimental data). RESULTS: Three different membrane processes were developed. The one in which the reaction mixture is recycled over a first dehydration membrane module and subsequently through a simple distillation column, was found to give the highest overall conversion (100%) at low recycle rates and reasonable membrane area. This process was techno‐economically compared with other possible alternatives: (1) a process based on a conventional tubular reactor and several distillation columns; and (2) a process based on reactive distillation. CONCLUSIONS: Efficient water removal by membranes avoids possible azeotropes in downstream distillation units making them much simpler, reducing considerably the unit sizes and the energy demand (40% lower). Copyright © 2012 Society of Chemical Industry 相似文献