共查询到19条相似文献,搜索用时 78 毫秒
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半个多世纪以来,世界各国的化学家,陶瓷学家及材料科学家与工程师们为发展与应用高性能的陶瓷材料进行了不懈的努力,并取得了巨大的进展,其中高纯,超细陶瓷粉末的制备技术更是受到了广泛的关注,研究的问题主要包括粉末的合成技术,粉末的特性,表面处理与形状的形成,粉末烧结行为及粉末-微观结构-性能关系等。本文试图对这方面的进展作一简要的概述,重点介绍粉末的制备技术。 相似文献
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以八水合氧氯化锆为锆源、正硅酸乙酯为硅源、蔗糖为碳源,采用液相先驱体转化结合溶胶凝胶法合成ZrC-SiC纳米复合粉体.借助傅立叶红外光谱仪分析了有机锆先驱体的官能团,借助X射线衍射仪和扫描电子显微镜研究了Si/Zr摩尔比对复合粉体物相组成与显微形貌的影响.研究表明:有机锆先驱体具有链状或网状结构;1450℃烧成并保温2 h,Si/Zr摩尔比0.28时复合粉体中仍存在未反应的m-ZrO2相,Si/Zr摩尔比增加至1.11、2.56、5.88、23.17时均合成了纯相ZrC-SiC纳米复合粉体;随着Si/Zr摩尔比的增加,复合粉体粒径变化不大;Si/Zr摩尔比为2.56时平均粒径仅90 nm,且元素分布均匀. 相似文献
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溶胶凝胶法,液相包裹法制备超细ZTM复合粉末 总被引:5,自引:0,他引:5
采用溶胶凝胶法、液相包裹法制备超细ZTM复合粉末,该复合粉末的组成分布均匀、颗粒呈球状、粒度分布窄且无明显硬团聚出现,其中氧化锆和莫来石粉末的粒径在10 ̄15nm。 相似文献
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The Fischer-Tropsch Synthesis in the Liquid Phase 总被引:3,自引:0,他引:3
The hydrogenation of carbon monoxide by the Fischer-Tropsch (F-T) process [1] forms saturated and unsaturated compounds of the homologous hydrocarbon series. It permits the synthesis of hydrocarbons ranging from methane to high-melting paraffins with molecular weights above 20,000, depending on the catalyst, temperature, and type of process employed. By-products such as alcohols, aldehydes, ketones, acids, and esters are formed on a smaller scale. Small amounts of aromatic compounds are formed at high temperatures by secondary dehydrocyclization reactions from the primary hydrocarbons formed. 相似文献
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水热法制备氧化锌陶瓷粉体中的形态调制 总被引:8,自引:0,他引:8
水热条件下制备超细微晶是一个晶体生长的过程。本文根据晶粒形态与水热介质碱度强弱之间的关系,揭示了不同形态的ZnO的形成机理,实现了水热法氧化锌陶瓷微晶制备过程中的形态调控。 相似文献
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Abstract The hydrogenation of carbon monoxide by the Fischer-Tropsch (F-T) process [1] forms saturated and unsaturated compounds of the homologous hydrocarbon series. It permits the synthesis of hydrocarbons ranging from methane to high-melting paraffins with molecular weights above 20,000, depending on the catalyst, temperature, and type of process employed. By-products such as alcohols, aldehydes, ketones, acids, and esters are formed on a smaller scale. Small amounts of aromatic compounds are formed at high temperatures by secondary dehydrocyclization reactions from the primary hydrocarbons formed. 相似文献
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M. I. Timokhova 《Glass and Ceramics》2004,61(3-4):117-119
The properties of molding powders of aluminum-oxide material VK 94-1 (containing 95% Al2O3) produced by drying in a spray dryer and their effect on the properties of molded samples are investigated. The technological process of molding refractory saggers using clay preliminary dried in a spray dryer is analyzed. Recommendations for further improvement of properties of saggers are issued. 相似文献