浸出过程的理论基础及实践李洪桂（中南工业大学长沙４１００８３）第六讲浸出过程在有色冶金中的应用（续）（３）针铁矿法根据１００℃下Ｆｅ２Ｏ３－Ｈ２Ｏ系的平衡图．在Ｆｅ３＋浓度很稀的条件下，Ｆｅ’“将形成针铁矿ａ—ＦｅＯＯＨ沉淀。针铁矿为一种很稳定的晶体...

The prospect of rare earths separation with a new extractantCyanex 272 was predicted by comparison of Cyanex 272 with P204 andP507. The recent study of solvent extraction for rare earths separationby Cyanex 272 has been reviewed. Some suggestions for the study arepresen ted.

This paper reviews several methods for the preparation ofcrys talline tare earth carbonates, and describes their applica non forrare earth extraction.

This artide describes the study and development of catalyst& pigment con taming rare metal elements.

The paper has reviewed the help of isostatic pressing technology for Be application and some isostatic pressing processes in beryllium manufacturing, and predicted it's development.

The influence of carbon on metallurgical Tapowder is brieflydescribed. The reason for necessity of carbon control in K2TaF7 and itsremoval methods during hydrometallurgy of Ta and Ni are presented.

The behaviour of various impurity during Nb refiningdiscussed. It is pointed out that liquid/liquid extraction and moltensalt electrolysis refining can effectively remove refractory Ta and Winpurity while electron-beam refining is conventionaly used for ordinarymetal impuri ty and low-melting-point impurity. Ultra-high-vacuum annealing can minimize the content of intetstitial solid-solution impurity,Oneprocess for high-purity Nb preparation is recommended, ie: Nb2O5extracnon→Nb2O5 reduction→electrolytic refining→electron beam refining→zone melting by suspended electron beam→ultra-high vacuum annealing→high-impurity Nb. Three new refining processes are finally described.

独联体国家的难熔金属氟化物化学气相沉积技术（下）李汉广（中南工业大学长沙４１００８３）３掌握了产品沉积结构的变化规律和优化条件难熔金属氟化物氢还原气相沉积时，可能得到五种类型的沉积结构（图８）：ａ．树脂状结构；ｂ．佳状结构；Ｃ．细晶结构：ｄ．层状结构...

The development of foreign cemen ted carbide technology isreviewed. the general description of the development of China 's cementedcarbide technology is made. Some suggestions are made for speeding-upthe development of China's cemented carbide industry.

This paper is a review Of the P/M history and P/M presentsituations in Hunan and gives some suggestions about rejuvenating HunanP/M industry.