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Mn~(2+)(Co~(2+)Ni~(2+))O_4材料制备中前驱物的影响 罗凤兰1,薄新维1,雷霆1 (1.重庆仪表材料研究所,重庆,400700;2.重庆科特传感技术有限公司,重庆,400700) 摘要:采用水热合成法,以Mn,Co,Ni的有机或无机盐和氨水为反应原料,通过调控前驱物配方,浓度等工艺参数在一定水热反应条件下,制备纳米粉体材料,利用XRD,TEM等手段分析了该粉体的晶相及杂质组成等性能参数.实验结果表明,采用硝酸盐和沉淀剂配制,中等盐溶液浓度的前驱物,在合适的条件下进行水热反应,合成了单一尖晶石结构,晶粒尺寸集中在20~50nm间的Mn~(2+)(Co~(2+)Ni~(2+))O_4粉体材料. 关键词:纳米; 水热法; 前驱物; nano; hydrothermal method; precursors; [全文内容正在添加中] ......
MOCVD法制备HfO2薄膜前驱体的研究现状 陈加林1,常桥稳1,刘伟平1,张妮1,余尧1,叶青松1,谌喜珠1 (1.昆明贵金属研究所,昆明,650106) 摘要:HfO2薄膜是一种新兴的薄膜材料,在耐高温保护涂层,微电子,催化等领域有着非常重要的应用.HfO2薄膜优异的性能及广阔的应用前景已经引起人们极大的关注.介绍了MOCVD法制备HfO2薄膜前驱体的研究进展和现状,着重讨论了MOCVD工艺中各类前驱体的优缺点,概述了目前研究的热点和进一步研究的方向.最后得出结论:目前使用较多的β二酮类铪配合物自身存在许多不利于MOCVD工艺的缺点,因此混合配体的铪配合物成为进一步研究的焦点. 关键词:HfO2; 薄膜; 前驱体; MOCVD; hafnium dioxide; films; precursors; MOCVD; [全文内容正在添加中] ......
液相先驱体制备ZrC粉末研究 苏勋家1,周晓波1,毕松1,王延斌2,侯根良1 (1.第二炮兵工程学院501教研室,西安,710025;2.中国人民解放军96263部队,洛阳,471500) 摘要:采用氯氧化锆,丙醇,丙三醇和乙酰丙酮为基本原料合成了锆的先驱体溶液,通过液相先驱体转化法合成了ZrC粉末.研究了先驱体溶液组成和热处理温度对合成ZrC粉末的成分和显微结构的影响,结果表明,随丙三醇用量的增加,干燥时间延长,提高碳和锆的物质的量比和温度都能够提高ZrC粉末的生成率.在高温热处理后合成了面心立方的ZrC粉末,1500℃处理后,粉末颗粒呈不规则的形状.1800℃热处理后,颗粒为球型,颗粒长大的趋势明显. 关键词:ZrC; 先驱体; 热处理; zirconium carbide; precursors; heat treatment; [全文内容正在添加中] ......
聚丙烯腈基炭纤维的制备 蔡华苏1,朱波1,王艳芝1,王延相1 (1.山东大学南校区材料学院炭纤维中心,山东济南,250061) 摘要:采用丙烯腈(AN)与衣糠酸(IA)自由基溶液共聚合,以偶氮二异丁腈(AIBN)为引发剂,在二甲基亚砜(DMSO)中合成了聚丙烯腈纺丝溶液,经湿法纺丝制得聚丙烯腈(PAN)原丝.在原丝牵伸的最后一段用CoSO4水溶液浸渍改性.利用SE M,TEM和热稳定化过程研究等方法进行对比研究改性前后纤维的结构与性能.结果表明:Co SO4能催化PAN原丝的热稳定化,环化反应,缩短预氧化时间,并能提高最终炭纤维的机械性能. 关键词:聚丙烯腈原丝; 改性; 结构与性能;......
410012, China)Abstract:Polycarbosilane containing beryllium (BPCS) precursors was prepared by the reaction of polycarbosilane (PCS) with beryllium acetylacetone (Be (acac)2). The analysis of structures and components of BPCS demonstrates that their main structures are basically the same as PCS. Ceramization of BPCS precursors shows that BPCS precursors are organic below 600 °C and inorganic at 800 °C......
of Technology摘 要:The precursors organic cerium deposits were obtained by a stripping precipitation method from cerium-loaded P507 organic phase using oxalic acid as a precipitating agent and nano-sized ceria particles were prepared by calcining the precursors at 500 °C. The morpholo-gies, phase structure of the precursors and ceria particles were characterized......
of Technology摘 要:The precursors organic cerium deposits were obtained by a stripping precipitation method from cerium-loaded P507 organic phase using oxalic acid as a precipitating agent and nano-sized ceria particles were prepared by calcining the precursors at 500 °C. The morpholo-gies, phase structure of the precursors and ceria particles were characterized......
precursors were prepared at room temperature with citric acid as the main leaching agent combined with other additives such as sodium citrate and H2O2. The ultrafine lead oxide powder was prepared from the precursors at low temperatures. The results show that the lead pastes can be leached, and crystallized lead citrate precursors are obtained. The rate of conversion of lead is above 98......
monodisperse and size-controllable erbium aluminum garnet (EAG) precursors for transparent ceramics were successfully synthesized through a new microwave process. The precursors constituted of ultrafine particles joining together by a hydroxyls formed compact network structure in the absence of SO42-, however, the morphologies of the precursors exhibited spheres with trace amount of SO42-. With manipulated......
monodisperse and size-controllable erbium aluminum garnet (EAG) precursors for transparent ceramics were successfully synthesized through a new microwave process. The precursors constituted of ultrafine particles joining together by a hydroxyls formed compact network structure in the absence of SO42-, however, the morphologies of the precursors exhibited spheres with trace amount of SO42-. With manipulated......
