Taking the state equation of cascade-extraction system for multi-component RE as basis. tile equivalent separation coefficient is adopted and the multi-component cascade -extraction system is described as equivalent double - component separation system with modified separation (coefficient. The calculation method for equivalent separation coefficient is presented and process design is made with respect to the multi -component casaoe -es traetion separation. Computer analog results show that the equivalent separation eoefficent is the minimun effective separation'coefficient from the extraction banks.

According to thermodynamics and by metallographic examination and EPM,the influence of Ce on oxide and sulphide in high-carbon low-alloy cast.steel has been studied. The result shows that with the addition of Ce to steel, the Ce-oxide, Ce-oxi-sulphide.Ce-sulphide will displace the oxide and the sulphide of other elements in steel. and type Ⅱsulphide seems to have disappered in steel. This is in accordance with thermodynamics. At the same time the steel cleanliness is markedly improved.

Ln2O3/X-13 sieve sorption (Ln= Nd,Sm,Tm,Lu, Dy ),prepared by immersioncalcination method,with 0.83% ~0. 93% RE oxides, has been proved to be quite effective as catalyst for esterification of aromatic phthalic acid or aliphatic acid with primary 2-ethylhexyl alcohol. For example. the conversion percentage of catalyst-bearing DOP is ~10% and 8% higher than that of catalyst-free DOP and X-13. And the conversion percentage of catalystbearing lOP is ~7% and ~4 % higher respectively than that of catalyst-free lOP and X-13. Furthermore, Ln2O3/X-13 sieve sorption contains ~25% less rare earth than Ln2O3/Al2O3 type esterification catalyst and esterification temperature is ~ 10℃ lower. It can be seen from the above that Ln2O3/X-13 sieve sorption is a very good esterification catalyst.

High-Content rare earth of 2-ethylhexoic acid has been synthesized by complex extraction method. The optimum synthetic conditions: the saponification rate of 2ethylhexoic acid is about 80%;the mole ratio of 2-ethylhexoic acid to rare earth is 3. 4: ;the reaction lasts 30 mins at 80℃. Its application in alchoholic acid paint proved its properties are up to or superior to the traditional drier standard.

Study is made on Ti recovery from Ti-bearing raffinate. The results show through NaCl desilication and addition of KCl (NaCl), the rough K2TiF6 (Na2TiF6). can be obtained from Ti-bearing raff mate. Then after recrystallization, purification, drying,KaTiF6 (Na2TiF6) product can be obtained. After water dissolution, ammonia precipitation,washing and drying, the enriched titanic acid product is calcined to obtain TiO2 for metallurgy or welding electrode. The recovery of Ti(as TiO2) from raff mate to K2TiF6 reached 89%, and 76% from raff mate to TiO2.

The effects of sintering temperature and time on synthesizing of MoSi2 from Mo and Si powder mixture are investigated by differential thermal analysis (DTA) and XRay diffraction. The initial sintering synthesizing temperature and resonable synthesizing technology of MoSi2 are presented.

study is made on PM Process for Mo-3% Re alloy. It was discovered that Mo3% Re alloy could be obtained by PM. 3% Rhenium addition can greatly decrease the grain sizes of molybdenum alloys. It was clear that the rhenium particle distribution was fairly homogeneous by wet or dry-wet mixing methods.

W-Ce is a W-doped product difficult to process, and the processed products often have defects such as cleavage and core wrapping. Study is made on the down-stream processing of W-Ce billet on the basis of experimental results and the suitable down-stream processing technology for the said product is found out.

Sample is solved with hydrochloric acid, and thin film is made with filter paper. using this thin film, Fe, Mn, Ni and Ca in cobalt oxide can be determined by x-ray fluorescence.

The thesis briefly presents Ancordense warm compaction process, equipment feature,unique property and its wide application.