【摘 要】
：
GdF3 was synthesized with Gd2O3 and NH4HF2 under atmospheric pressure and vacuum. The effects of pressure,temperature, and reactant ratio on the reaction proces
【机 构】
：
Metallurgical and Ecological Engineering School, University of Science and Technology Beijing, Beiji
论文部分内容阅读
GdF3 was synthesized with Gd2O3 and NH4HF2 under atmospheric pressure and vacuum. The effects of pressure,temperature, and reactant ratio on the reaction process were investigated. A new mechanism for the synthesis of GdF3 was proposed. Powdered Gd2O3 started to react with NH4HF2 at low temperature, and the products were GdNH4F4, NH4F, NH3,and H2O. GdNH4F4 decomposed to GdF3 and NH4F after further high-temperature treatment, accompanying the volatilization and decomposition of NH4F. The whole process could be divided into three steps: synthesis, decomposition, and deamination. The initial and final reaction temperatures decreased under vacuum condition. An optimized process for the preparation of GdF3 was obtained: synthesis under atmospheric pressure at low temperature and decomposition and deamination under vacuum at high temperature.
其他文献
The hardness measurement, optical microscopy (OM), and transmission electron microscopy (TEM) microstructure observation on the annealing behaviors of Cu-Al2O3
根据集宁区地下水监测结果,《生活饮用水卫生标准》GB5749-2006中的地下水质量分类指标,利用饮用水水质评价、地下水质量评价及工业用水水质评价,确定集宁地下水水质。
Acco
Cu(OH)2 nano-fibers were prepared by chemical precipitation with CuSO4·5H2O and NaOH as raw materials.The Cu(OH)2 nano-fibers have a diameter of 10-30 nm and a
Silver tin oxide composite powders were synthesized by the hydrothermal method with a silver ammine solution and a Na2SnO3 solution as raw marrials. H2C2O4 was
目的了解东洞庭湖湿地保护区环境标本中禽流感病毒分布情况。方法根据《2011岳阳市东洞庭湖湿地保护区职业暴露人群感染禽流感的风险研究项目工作方案》的要求,采集环境水及
鄭玄《論語注》中包含經說,多與《論語集解》所收古注相牴牾.以往研究表明,鄭注立足於三《禮》之學,為鄭玄注異於何晏《集解》之突出特色.然而鄭注中另一部分則無關乎禮學,蓋
亚当·斯密是英国著名的道德哲学家、古典经济学家,他有两部传世之作《道德情操论》与《国富论》,历经两百多年依然影响至今。《道德情操论》是斯密最为得意之作,前后共修改5
《大乘百法明门论开宗义记》由唐代僧人昙旷所作，成书於公元八世纪。这是一部关於《大乘百法明门论》的注疏，虽然主要解释五位法相，但文中包含内容较多，是研究唐代敦煌唯识学重要
研究了从石煤氧压酸浸液中萃钒除铁的工艺过程,从萃取和反萃的相比、试剂组成、pH值、澄清时间等方面进行了详细试验.研究表明:浸出液经中和还原处理后,采用10%P204+5%TBP+85