The GdF3:Eu3+and NaGdF4:Eu3+powders were synthesized by hydrothermal method as raw material of Gd2O3, Eu2O3, NaF, NH4HF2, EDTA and polyethylene glycol. The powders were characterized by means of X-ray powder diffraction, SEM microscopy and Molecular fluorescence photometer. It was discussed that the pH value of aqueous solution had affection on the phase composition of synthesized powders. The complex fluorides GdF3and NaGdF4were synthesized in aqueous solution at the pH values between 3 and 6. The synthesized powders were single hexagonal phase of NaGdF4 crystal at pH=8. It was also found that different fluorescence properties were exhibited by Eu3+doping powders synthesized at different pH values of aqueous solution. The synthesized powders of GdF3and NaGdF4were excellent fluorescence materials.

As the raw materials of Na2WO4•2H2O and ZnSO4•7H2O, ZnWO4 micron spheres and nanorods were synthesized with CH3COOH as the complexing agent by a hydrothermal method at 180 °C for 24h. We analyzed the effect of different pH values in reaction solutions on phase compositions, morphologies and luminescent properties of the ZnWO4 powders. The as-synthesized products were characterized by XRD and SEM. The down-conversion spectrum was measured with spectrophotometer under the excitation wavelength of 291nm. The results indicated that there was a wide emission peaks at 400~550nm. The luminescent intensities of ZnWO4 nanorods synthesized at pH value of 9, 10 and 11 were much stronger than that of ZnWO4 micron spheres synthesized between the pH values of 4 to 8.

The nano-inorganic polymer coagulant, poly-ferric-aluminum-silicate-sulfate (PFASS) modified by quick lime were prepared from oil shale ash, which were evaluated by treating sewage. The following results are discovered: The samples contain (CaO)xSiO2•zH2O, Fe2(SO4)2(OH)•5(H2O), NaAl(SO4)2•(H2O)6 and other crystal; PFASS are complicated compounds by iron, aluminum, silicon and other ions rather than simple mixtures of raw materials. The optimal coagulant dosage is about 80-100 mg/L for the turbidity removal, and the range of the suitable dose is wider for COD removal, the optimal dose of quick lime is 2.5 g for turbidity removal and 3 g for COD removal.