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Using Gas Chromatography and Fourier Transform Infrared Spectroscopy (FT-IR), the content of metal impurity element and gas-liquid inclusions in natural crystal and ordinary silica mine of different mining area had been studied. The characteristics of silica mine which was suitable for microwave-acid etching process to remove gas fluid inclusion in quartz sand had been discussed.Our results showed that the silica mine which had low content of impurity, less content of gas-fluid inclusion and high water filling degree was suitable for the microwave-acid etching process to remove gas-liquid inclusion in quartz sand; the content of metal element impurities in quartz sand from Madagascar was nearly close to the primary natural crystal, had less content of gas-fluid inclusion and high water filling degree, and was suitable for the microwave-acid etching process to remove.

This article studies on flotation of quartz using magnesium ion as activator in the system of dodecyl sulphate，studies of magnesium ion on ZETA potential of the quartz surface and the flotation recoveries of the quartz through flotation experiment, ZETA potential measurement and infrared spectroscopy and solution chemistry of magnesium calculation. The results show that ZETA potential of the quartz surface showed negative charge when the pH＞2，is not conducive to the adsorption of the anionic collector dodecyl sulphate. When adding magnesium ion, ZETA potential began to rise sharply, and the recovery rate of the quartz began to increase sharply at pH = 8. ZETA potential of quartz surface show positive charge, and the recovery rate of the quartz is corresponding to the maximum within pH=10-12. Combined with the solution hydrolysis of magnesium ion, it can be determined, Mg(OH)+ is the main active ingredient that activate flotation of quartz in the system of anionic collector dodecyl sulphate, and when magnesium hydroxide reaches a certain concentration, flotation of quartz began to be inhibited.

The impurities and gas-liquid inclusions in quartz sand, which are from our country and UNIMIN Corporation respectively, were analyzed by Inductive Coupling Plasma Emission Spectrograph（ICP-AES）and Fourier Transform Infrared Spectroscopy (FT-IR). The results showed that the biggest difference between them was the content of gas-liquid inclusions. Thus, in order to improve the quality of our country high purity quartz sand, development of new technology to remove gas-liquid inclusions has been imperative. Method for removal of gas-liquid inclusions, using microwave radiation, was studied in this project. Meanwhile, the change of microscopic morphology of gas-liquid inclusion was observed by polarizing microscope. And the change of water content in gas-liquid inclusion was investigated by Fourier Transform Infrared Spectroscopy. Our results showed that micro-crack could be produced on the surface of gas-liquid inclusion under microwave treatment. The results also showed that new water molecules and liquid inclusions could be generated in the process. Furthermore, these liquid inclusions could be removed and H2O could be reduced by HF acid leaching.

This article studied on calcium ions affecting mechanism to collecting quartz in the system of dodecyl sulphate. Studied calcium ions on Zeta potential of quartz surface and flotation behavior through flotation experiment, Zeta potential measurement, infrared spectroscopy and solution chemistry of calcium calculation. The results show that the ability of collecting quartz by anionic collector dodecyl sulphate is weak within pH range of 4-14, and basically can be seen cannot collect quartz. When adding calcium ions, the capacity of collecting quartz increases significantly. By Zeta potential of quartz surface, when pH>2, Zeta potential of the quartz surface shows negative charge, is not conducive to the adsorption of the anionic collector dodecyl sulphate. When adding calcium ions, Zeta potential increases significantly, and at pH = 10, Zeta potential begin to rise sharply, at this point, the concentration of Ca(OH)+ in the solution composition of calcium is also started to increase, and the recovery rate of the quartz begin to increase sharply. The concentration of Ca(OH)+ is the maximum within pH=11.5-13.5, and Zeta potential of quartz surface shows positive charge, and the recovery rate of the quartz is corresponding to the maximum. So can be determined, Ca(OH)+ is the main reason of affecting Zeta potential of the quartz surface, and Ca(OH)+ is the main active ingredient that activate flotation of quartz in the system of anionic collector dodecyl sulphate.

Fe-Mo/Si3N4 cermet powers are prepared by heterogeneous precipitation-thermal reduction process and sintered on normal pressure with Y2O3-MgO additives.The effect of sintering temperature on the phase composition, microstructure and mechanical properties are discussed. Result of study indicates: the rise of sintering temperature is beneficial to retention the metal phase and the generation of β-Si3N4 whisker. At the temperature of 1650℃, Y-Mg-Si-O-N glass phase is generated, At the temperature of 1700℃, whiskers-like β-Si3N4, good wettability phases on Si3N4 surface, and high toughness Fe phase appeared in Fe-Mo/Si3N4 cermets. It can effectively better the microstructures of Fe-Mo/Si3N4 cermets, and contribute to improve the material mechanical perperties. When the temperature rise to 1750℃, the maximum particle MoSi2 can destroy the microscopic structure, and decreases the density and mechanical properties of ceramics fast. The optimum sintering temperature is therefore about 1700℃.

Based on epoxy resin, Aradur9506 as curing agent and Flake silver powders, isotropic conductive adhesives(ICA) were prepared, The effects of the functional groups of epoxy resin and the addition of curing agent in isothermal cure on the resistivity of the ECA were investigated by FT-IR method, scanning electron microscopy（SEM）and other means. The results indicated that tensile shear strength declined with the increased in the number of epoxy functional groups and raised with the addition of curing agent, and the tensile shear strength was inverse relationship with the curing shrinkage