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Jacques Darné 《Journal of Pure and Applied Algebra》2019,223(12):5484-5525
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Haithem Bel Hadjltaief Maria Elena Galvez Mourad Ben Zina Patrick Da Costa 《Arabian Journal of Chemistry》2019,12(7):1454-1462
A TiO2-coated Tunisian clay (TiO2–clay) was synthesized by a typical impregnation method. The physicochemical characterization points to a successful impregnation of titania on the clay surface. The activity of this structured catalyst was studied in the photocatalytic/photochemical oxidation of anionic reactive blue 19 (RB 19). The effect of UVA and solar irradiation (UV-solar) was studied at room temperature. TiO2–clay demonstrated an effective degradation of RB 19 under both types of irradiation. Moreover, in this study, the effects of various oxidants such as hydrogen peroxide (H2O2), potassium peroxodisulfate (K2S2O8) and sodium carbonate (Na2CO3) were thoroughly investigated. H2O2 was a promising oxidant for promoting RB 19 degradation under UVA. The kinetics of discoloration of RB 19 followed a pseudo-first-order rate law. We can remark that 20 min of UV irradiation was enough to achieve 100% discoloration of the aqueous solution. However, under UV–Vis, HPLC and chemical oxygen demand measurements indicated, that a longer reaction time (of around 45 min) was required for achieving the complete dye mineralization. The findings clearly demonstrated the applicability of this TiO2/clay catalyst for the photocatalytic oxidation of RB 19. 相似文献
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J.C. Gâcon A. Gros H. Bill J.P. Wicky 《Journal of Physics and Chemistry of Solids》1981,42(7):587-593
The fluorescence of divalent samarium in KMgF3 and NaMgF3 crystals is investigated. The emission is observed to originate from transitions between the 5DJ, and 7FJ multiplets of the 4?6 configuration. More precisely, the lowest 5DJ level, 5D0, appears to be the most efficient emitting level in the temperature range 4–300K. Contrary to what has been reported elsewhere, the Sm2+ fluorescence in both crystals does not exhibit any broad band emission even at room temperature. The great number of lines in the 5D0→7FJ patterns gives evidence of the multiple-center origin of the fluorescence. 相似文献