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as nitrogen precursor are encapsulated in a compact silica shell which provides a confined nano-space for the pyrolysis treatment. The in situ generated gases from mesoporous polymer sphere and 2-methylimidazole under pyrolysis diffuse into the pores of mesoporous polymer sphere in the confined compact silica shell,resulting in increased surface area, larger pore size and N-doping due to self......
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cm~3/g逐渐增加到2.708 cm~3/g,比表面积由455.3 m~2/g增加到1063 m~2/g,说明随着甲醇添加量的增加,介孔逐渐向微孔方向扩展. 关键词:介孔氧化硅; 甲醇; 微结构; 形貌; mesoporous silica; methanol; microstructure; morphology; [全文内容正在添加中] ......
Effects of precoating and calcination on microstructure of 3D silica fiber reinforced silicon nitride based composites QI Gong-jin(齐共金), ZHANG Chang-rui(张长瑞), HU Hai-feng(胡海峰) State Key...: Three-dimensional silica fiber reinforced silicon nitride based composites were fabricated by preceramic polymer infiltration and pyrolysis method using perhydropolysilazane as a precursor......
Hengyong, BI Yadong, et al. Recent progress of modification of mesoporous silica SBA-15[J]. Chemical Industry and Engineering Progress, 2007, 26(2): 152-157. [5] Zhao D Y, Huo Q S, Feng J L, et al. Nonionic triblock and star diblock copolymer and oligomeric surfactant syntheses of highly ordered, hydrothermally stable, mesoporous silica structures[J]. Journal of the American Chemical Society......
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of drying conditions on structural and surface heterogeneity of silica aerogels and xerogel by using cryogenic nitrogen adsorption characterization[J]. Microporous and Mesoporous Materials, 2010, 129: 1-10...): 3130-3133. [20] Hwang S W, Kim T Y, Hyun S H. Effect of surface modification conditions on the synthesis of mesoporous crack-free silica aerogel monoliths from waterglass via ambient-drying[J......
J. Cent. South Univ. Technol. (2007)06-0737-05 DOI: 10.1007/s11771-007-0140-y Viscoelastic properties of monodisperse spherical silica suspension WU Qiu-mei(伍秋美), RUAN Jian-ming(阮建... properties of the suspension of monodisperse spherical silica produced by hydrolysis of tetraethoxysilane in alcohol solvent with ammonia as a catalyst in polyethylene glycol (PEG) were studied. The results......
高结晶规则大孔硅的制备和应用 高桥治雄1,李波1,稻恒伸一1,宫崎千绘1 (1.日本丰田汽车集团公司中央研究所) 摘要:FSM-16,MCM-41和SBA-15等具有高规则二维六角晶格的多孔硅可用不同硅源和表面活性剂合成,其孔径可达10,15或30 nm,可用具有不同烷基链长的表面活性剂和膨胀剂控制其结晶规则性随孔径的增大而降低.用层状硅土Kanemite制备的FSM-16和来自水玻璃的MCM-41,其表面阴离子度比用四甲氧基硅烷(TMOS)制备的SBA-15高得多.如将在等电点以下呈阴离子性的生物酶插入硅孔,则由于离子间的相互作用和氢键结合力,可得到结合得十分稳定的生物/无机陶瓷结合体.以此结合体作为有机酸化反应的催化剂,反应的活性很高. 关键词:多孔硅; 表面活性剂; 膨胀剂; 生物酶; 活性; KEY WORDS mesoporous silica; surfactant......
低成本制备孔容和孔径可控的介孔二氧化硅 郭锴1,沈淑玲1,毋伟2,陈建峰1 (1.北京化工大学教育部超重力工程研究中心,北京,100029;2.北京化工大学纳米材料先进制备技术与应用科学教育部重点实验室,北京,100029) 摘要:通过可控的溶胶凝胶过程,使用廉价的水玻璃为硅源,氨水为助剂制备了孔容和孔径可控的介孔二氧化硅.研究了溶胶凝胶过程中的影响因素.结果表明,控制氨水/二氧化硅的比例,水玻璃的浓度,凝胶温度和终点的pH值可以制备出介孔二氧化硅.制备的介孔二氧化硅的主要特点包括孔容高和孔径可调. 关键词:溶胶凝胶; 介孔二氧化硅; 大孔容; 孔径可控; 低成本; sol-gel process; mesoporous silica; large pore volume; tuned pore size; low-cost; [全文内容正在添加中] ......