The nano-crystal composite WO3-TiO2 photocatalyst is prepared by sol-gel process in ultrasonic filed. Study is made of the effects of ammonium tungstate dosage,number of film coatings, sintering temperature and duration, various substrates,pH value,dissolved oxygen and the ultrasonic on the photocatalyric activity in the light of the film photo-degradation of rhodamine B. The results show that when compared with conventional sol-gel process,in the untrasonic field the gelating time of the sol is remarkably shortened, the particle size of the photocatalyst diminishes evidently and the photocatalytic activity increases significantly. The highest photocatalytic activity of WO3-TiO2 film is obtained with ammonium tungstate 0.5 % （mass）, the porous Ti plate as sub strate, 9 layers of film coating, 1 h sintering at 575℃. resulting in the WO3-TiO2 film almost all of rutile TiO2.

La1-xSrxMnO3 cathode material of solid oxide fuel cells is prepared by SHS method. Study is made of the relationship between Sr content and sintered LSM strength and relative density as well as the variation of porosity and expansion coefficient of the sintered specimen with different temperature. It is found that the particle size becomes larger and the relative density is slightly reduced with the increase of Sr content. Higher sintering temperature is good for less porosity. The thermal expansion coefficient of the sintered specimens matches well with that of YSZ.

In this paper, TiB2 powder of 99.34% purity is prepared by vacuum carbothermic reduction of TiO, and B2O3 based on the thermodynamics analysis of the reaction TiO2＋B2O3＋5C→TiB2＋5CO↑ The investigation results show that the actual reaction temperature can be decreased by about 200℃ by vacuum carbothermic reduction for TiB2preparation. Vacuum is very important for high purity TiB2 powder,while excessive amount of carbon in proper ratio can remarkably, enhance TiB2 purity.

Study is made of the optimum technological conditions for recovery of TiO2 by flotation of waste residues from titanium white acid hydrolysis. At feed grade 24. 44%, the concentrate grade can reach 46.86% with TiO2 recovery up to 85.46%. The flotation process is simple and easy to be used in commercial scale production.

The mixed powder of WO3,Co3 O4 and carbon was in-situ synthesized to get the dense WC-Co Hardmetal by spark plasma sintering technique. The effects of the synthesis parameters and the carbon contents on the phase composition, the density and microstructure of the alloy have been studied. The results showed that the carbon can rapidly reduce the Co3O4 to Co,reduce the WO3 and directly carbonize it to WC under 970℃ ,leading to a sintering reaction with further temperature increase. With low carbon content,Co3 W9C4 and Co3 W3 C exists in the alloy as impurity. Only with appropriate carbon content,the physical composition of the alloy is WC-Co and the density of the alloy can be near the theoretical density with a grain size of about 0.5μm.

Study is made of the effects on the carbon content and its rule during the mixing, degreasing and sintering of WC-Co cemented Carbide. The effective approach of control of carbon is presented in this paper.

One brand of carbide has been made from two different raw materials. Their microstructures were observed by means of TEM,and existence of W2C, WC1-x phases in WC phase was ascertained by electron diffraction. The slip, twin deformation properties of WC phases was also investigated by application of strain on alloys. The results show that, when WC phase is as singlephase,it can generates twin-slip coordination deformation, thus the alloy exhibits high toughness, this high-plastic alloy is applicable for rock drilling.

K2ZrF6 is reduced with liquid Mg and KCl and NaCl as flux. High-quality Mg-Zr intermediate alloy is produced through control of furnace charge proportion, reduction temperature and time,and by forward and backward mechanical agitation, successfully solving the problem of separation between the slag phase and Mg-Zr intermediate alloy,of somewhat higher impurity in the alloy and alloy constituent segregation from the traditional production process.

Study is made of a new process for directly extraction of the cobalt oxalate from ammonium oxalate in the acid solution directly dissolved from lithium cobaltate. Aluminum in the acid solution is completely complexed with F salt. Then,cobalt is precipitated with ammonium oxalate at pH= 2 and under 60 ℃. Finally,the cobalt is calcined into cobalt oxide in the muffle. To obtain the product,which is up to the requirement of the Co2O3-Y1（ehinese code GB6518-86）. The dosage of the F salt is 110% of the theoretic dosage; while the dosage of ammonium oxalate can be reduced by 50 %. The rate of cobalt precipitation with ammonium oxalate is 99.37%.

Brief analysis is made of the development of cemented carbides both at home and abroad and also the current production in China＇s cemented carbide industry. The paper describes the necessity for development of good quality cemented carbide materials. Analysis is also made of the latest development of cemented carbide for rock drilling.