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以混合稀土为原料,采用机械力固相化学反应首先制备出前驱体,用DTA-TG分析前驱体的热分解温度,然后将前驱物热分解2.5h,得到二氧化铈粉体,用XRD、SEM和TEM进行表征。结果表明获得了平均粒径在小于100nm、分布均匀的纳米CeO3。 相似文献
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以八水氯氧化锆和草酸钠为原料,固相反应合成出前驱体二水草酸氧锆,前驱体在600℃分解5 h,得到氧化锆粉体。结果表明,产物为粒度分布均匀、纯度高、单斜相和四方相共存的纳米氧化锆粉体,其一次颗粒尺寸在15 nm左右。 相似文献
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以氧氯化锆和硝酸钇及碳酸氢铵为原料,PEG4000为分散剂,在撞击流反应器中制备钇稳定氧化锆前驱体,焙烧后得到钇稳定氧化锆(YSZ)粉体,考察PEG4000用量、搅拌速率、反应时间和焙烧时间对粉体粒径的影响,并对粉体进行表征。结果表明,优化工艺条件为:PEG4000用量1.4g/L,转速1 000r/min,反应时间65min,前驱粉体在1 460℃焙烧120min,可制得球形、粒度分布均匀、表观直径小于0.5μm的YSZ超细粉体。 相似文献
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采用氯化钇溶液为原料,草酸/草酸铵为复合沉淀剂,采用共沉方式,得到氧化钇的前驱体,经灼烧后制得Y2O3粉末。研究了复合沉淀剂的组成、料液浓度、反应温度、加料速度等对沉淀颗粒大小的影响。结果表明,在选定条件下,采用草酸/草酸盐为复合沉淀剂能够制备出D50小于1.0μm的超细氧化钇粉末,可用于高性能稀土复合钇锆陶瓷的原料。 相似文献
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以草酸为沉淀剂,P507-N235-磺化煤油-环己烷体系分离稀土过程中的氯化钕反萃余液为原料,制备了大粒度氧化钕.采用激光粒度仪结合扫描电镜对样品进行粒度、形貌分析;使用X 射线衍射对前驱体煅烧样品进行物相分析,结合差热分析研究前驱体的热分解过程.沉淀过程中草酸钕前驱体粒度的主要影响因素为反应温度、搅拌速度、沉淀剂滴加速度及陈化时间,其最佳制备条件为反应温度50℃,搅拌速度300 r/min,沉淀剂滴加速度9 mL/min,陈化时间24 h.对比实验表明,氯化钕反萃余液中残余的有机相可以有效地增大前驱体的粒度.草酸钕前驱体在煅烧温度800℃下保温2 h可完全转化为Nd2O3,氧化钕粒径达到50μm以上. 相似文献
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针对液相沉淀法制备纳米Y2O3粉体工艺的焙烧过程中粉体易团聚问题,以碳酸钠和碳酸氢钠混合沉淀剂沉淀获得的纳米碱式碳酸钇为对象,系统研究了其焙烧条件对Y2O3形貌和粒度的影响以及动力学行为。研究表明:在煅烧温度860℃、升温速率5.375℃/min、焙烧时间1 h的条件下,得到D50=0.050μm,(D90―D10)/(2D50)=0.98,分散性良好的纳米Y2O3,其形貌与前驱体碱式碳酸钇相似。碱式碳酸钇前驱体(Y(OH)CO3·H2O)焙烧制备纳米Y2O3粉体的热分解过程分为两个阶段:第一阶段,Y(OH)CO3·H2O分解生成Y(OH)CO3,该反应过程的表观活化能E为90.23 kJ/mol,指前因子A为7.46... 相似文献
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实验结果表明,M17铸造高温合金(%:0.16C、8.79Cr、5.79A1、4.93Ti、3.29Mo、15.20Co、0.78V、0.015B、0.073Zr、0.002S、0.001P、0.001 1O、0.001 0N)经25 kg真空感应炉返回重熔后,Si含量随重熔次数的增加而略有增加,合金中主要元素和其它杂质元素S、P、H的含量变化不大,而氧、氮略有增加;合金中初生碳化物由新合金中的草书体逐渐向返回合金块状转变,初生碳化物的遗传性堵塞合金凝固时的补缩通道,使返回料合金的疏松倾向增大,高温塑性下降较大。 相似文献
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正Shijiazhuang City will build the world’s biggest replacing-copper-with-aluminum cable production base,the annual output value can reach 100 billion yuan,in the future it will develop replacing-copper-with-aluminum highend industry cluster.This piece of news was learned by the reporter at the Rare Earth highiron Aluminum Alloy[Nonferrous Business Opportunity:Aluminum alloy door]Cable Conductor New Technology Application Seminar held at the provincial capital. 相似文献
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《China Nonferrous Metals Monthly》2014,(12)
正Since the beginning of Chongqing’s upgrading to a municipality directly under the Central Government,Chongqing City has established direct friendly relationship with Almaty,Kazakhstan,and carried out a series of cooperation in commerce and trade,and culture 相似文献
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《China Nonferrous Metals Monthly》2014,(10)
正"For each tonne of aluminum being produced,the upstream enterprise on the aluminum industrial chain will suffer loss about 2000yuan."Said Liang Xiao,Deputy Director of Pingguo Industrial Park Management Committee under the Guangxi Baise City,one of the four major aluminum industry bases in China,on August 11.Extending aluminum 相似文献
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正Immediately after the news that Chinalco transferred 58%stock equity of Yunnan Copper Group to its wholly-owned subsidiary China Copper Corporation Limited free of charge was disclosed on July 9,many individual investors couldn’t help but to think:Does it mean China Copper Corporation Limited will assemble assets for overall listing?At present,among main copper business companies under China Copper Corporation 相似文献
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正At the press conference recently held by the National Development and Reform Commission under the theme"Deepen Reform in Investment AuditApproval System",when answering questions from reporters,Huang Min,Director of the Department of Fixed Assets Investment of the National Development and Reform Commission,said that in the future it would continue to intensify efforts in geological prospecting,and actively guide social capital to enter this field. 相似文献
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正Recently,Guangxi Metallurgical Research Institute,a subsidiary of Guangxi Nonferrous Metals Group,completed survey on laterite and related manufacturers in the region,by combining the current development status of laterite both at home and abroad,it compiled Guangxi’s first"Research Report on the Development of Guangxi Nickel Industrial Chain"which adopted laterite as the study subject.This report expounded on the current 相似文献
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