Ta2O5 powder was prepared by neutralization crystallization and calcination.The influences of the six factors in the process of neutralization crystallization on the Ta2O5 particle size were studied including the concentration of tantalum solution,the initial pH of tantalum solution,crystallization temperature,ammonia concentration,ammonia flow rate and stirring speed.The optimal experimental conditions are as follows：the concentration of tantalum solution is 95 g/L,the initial pH of tantalum solution 1.80,crystallization temperature 60 ℃,ammonia concentration 8.0 mol/L,ammonia flow velocity 1.0 mL/min,and stirring speed 40 r/min.Prepared under the above conditions,Ta2O5 powder has the largest average particle size of 1.80 μm and fully meets with the production requirement.

CaTi4（PO4）6 bioceramic membrane was directly prepared by micro-arc oxidation,and the effects of electrolyte concentration on the growth of micro-arc oxidized membrane were investigated.The results show that the weight of micro-arc oxidized membrane increases linearly with reaction time prolonged under the same electrolyte concentration.With electrolyte concentration increasing,membrane weight increases faster,membrane formation time shortens and breakdown voltage lowers,and Ca content of membrane surface increases while P content has little change.However,after the electrolyte concentration has increased to a certain extent,increasing electrolyte concentration will result in the decrease of Ca and P content on membrane surface.

LaSrCo composite oxide was synthesized by hydrothermal process at 180 ℃ for 24 h,using lan-thanum nitrate,strontium nitrate and cobalt nitrate as the metal starting materials and citrate as the complexing agent. XRD patterns show that the product is composed of the La0.8Sr0.2CoO3-δ phase with orthorhombic hexahedral perovskite structure. SEM images show that the product is composed of 0.5 ~ 1um pherical particles. And infrared absorption spectra demonstrate that the product is composed of the main Lao.sSro.2CoO^-e component and a little residual citrate acid and adsorbed water. There are two small absorption peaks at 326 nm and 385 nm in ultraviolet absorption spectra of the product, which may be caused by the grain-boundary defects of La0.8Sr0.2CoO3-δ phase.

The Mo-La2O3 slab was prepared by liquid-liquid doping and powder metallurgy,and then rolled into plate.After annealing at different temperature,the tensile strength of the Mo-La2O3 plate was tested at room temperature.The fracture surface of the Mo-La2O3 plate and its La2O3 content and distribution were analyzed by SEM and EDS.The results show that the elongation of the Mo-La2O3 plate is higher than pure molybdenum plate.The room temperature tensile strength of the Mo-La2O3 plate increases significantly with the La2O3 content increasing.The dimple-shaped fracture changes into a cleavage-type one with annealing temperature rising.La2O3 is distributed in the grain or on grain boundary,which can greatly reduces the impurity content on grain boundary,inhibit the growth of microscopic holes and micropores,and then improve the strength and toughness of molybdenum plate.

The effects of double aging on mechanical properties and corrosion resistance of the Al-Cu-Li-Zr alloy containing Sc were studied by tensile test at room temperature,TEM and corrosion experiment.The results show that the alloy treated with double aging can show optimal comprehensive properties of strength and plasticity.Compared with the alloy treated with T8 peak aging,that with double aging has improved elongation even without its strength reduced.The main precipitated strengthening phase of the alloy is T1 phase.After double aging,fine and dispersive T1 phase precipitates in the grain interior,distributed uniformly in the alloy to improve its corrosion resistance.

The ITO powders were prepared by chemical precipitation and then used to prepare the ITO target material by spraying drying-cold isostatic pressing-sintering.The surface morphology and pore distribution of powder,bisque body and sintered ITO target material were examined by SEM.The influences of different powder particle size distribution on pressing and sintering of the target material were discussed.The results indicate that the ITO target material with a relative density over 97% can be obtained by spraying drying-cold isostatic pressing-sintering.Spraying drying can effectively enhance the fluidity and pressing performance of powder,and the bisque body mainly composed of small particles shows a higher sintering density.

The red phosphor of Y2O3∶Eu3＋was synthesized by microwave heating.The effects of such fluxing agents as carbonate,fluoride and boric acid on the synthesis process and the luminescence performance of Y2O3∶Eu3＋ were studied.Spectrometer and laser particle sizer were used to analyze the photoelectric parameters and particle sizes of the prepared phosphor.The results show that the addition of different fluxing agents cannot change the position of the main emission peak（610 nm）,but remarkably change the luminescence performance and particle sizes of the phosphor sample.The sample employing carbonate as its single fluxing agent is of higher relative brightness than that employing fluoride.And the samples applying compound fluxing agents have more excellent performance than those applying single fluxing agents,including relative brightness and particle size.

The activation level and impurity control index were calculated and analyzed initially based on irradiation dose rate.And the aim is to provide basic data for out-pile tritium release experiment from lithium-lead alloy and for the establishment of the personnel safety operation rule and regulation to ensure the absolute safety of irradiation experiments and tritium release experiments.The results show that the dose rate of Li-Pb alloy is reduced up to the dose rate level requirement of radiochemical laboratory operation,and the impurity control level is low under 15-hours irradiation at the neutron dose rate of 1013N/（cm2·s） and 10-months cooling and storage.However,the general chemical laboratory operation requirement cannot be met even by 100-months storage.

The latest development of cemented carbide tool material is introduced.The development trends of nano-composite strengthening and laser surface strengthening are summarized.The discussion is made about the key problems of nano-grain growth inhibition and structure densification in the strengthening technologies.

The nano-cemented carbide samples of 92WC-8Co were prepared by spark plasma sintering.The influences of sintering pressure on the grain size,structure,density and hardness of 92WC-8Co alloy were studied.