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In this study, we successfully prepared pure, mono-doped, and Ag, Mg co-doped TiO2 nanoparticles using the sol–gel method, with titanium tetraisopropoxide as the Ti source. The prepared samples were characterized by X-ray powder diffraction (XRD), specific surface area and porosity (BET and BJH) measurement, scanning electron microscopy, transmission electron microscopy, X-ray photoelectron spectroscopy, photoluminescence, and energy dispersive X-ray spectroscopy techniques. The XRD data showed that the prepared nanoparticles had the same crystals structures as the pure TiO2. Also, DRS results indicated that the band gap of co-doped photocatalyst was smaller than that of the monometallic and undoped TiO2 and that there was a shift in the absorption band towards the visible light region. Furthermore, the photocatalytic activity of the prepared catalysts was evaluated by the degradation of C.I. Acid Red 27 in aqueous solution under visible light irradiation. The results showed that Ag (0.08 mol%), Mg (0.2 mol%) co-doped TiO2 had the highest photoactivity among all samples under visible light. It was concluded that co-doping of the Ag and Mg can significantly improve the photocatalytic activity of the prepared photocatalysts, due to the efficient inhibition of the recombination of photogenerated electron–hole pairs. The optimum calcination temperature and time were 450 °C and 3 h, respectively.  相似文献   

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Five solvates, [CdBr2(DMF)] n , [CdBr2(DMA)] n , [CdI2(DMF)] n , [Cd(DMF)6][Cd2I6], and {[Cd(DMA)6][Cd5I12] n } m , were isolated from the ternary systems CdX2–L–H2O (X = Br, I; L = N,N-dimethylacetamide, N,N-dimethylformamide) and characterized by the X-ray single crystal analysis. The structures of the first three solvates is similar to each other in structures and represent a one-dimensional polymer chain, the fourth solvate has the discrete structure containing [Cd(DMF)6]2+ and [Cd2I6]2– ions, and the fifth solvate contains discrete [Cd(DMA)6]2+ cations and the polymer anionic fragment [Cd5I12] n 2n.  相似文献   

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A simple and effective general method of synthesis of α- and β-diphenylphosphorylated secondary alkanols by the reduction of the corresponding phosphorylalkanones with NaBH4 was developed. The extraction properties of the resulting phosphorylalkanols Ph2P(O)(CR2)nCH2CH(OH)Me (n = 0, 1; R = H, Me) were studied in the recovery of f-elements (LaIII, NdIII, HoIII, YbIII, UVI, ThIV) from nitric acid solutions into chloroform and compared with those of both related phosphorylketones and known extractants (n-BuO)3PO, (n-C8H17)3PO, and Ph2P(O)CH2C(O)N(n-Bu)2.  相似文献   

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对Nonlinear Polymer Rheology:Macroscopic Phenomenology and Molecular Foundation(高分子非线性流变学:宏观唯象学及其分子基础)流变学专著进行了全面深入的分析与评价.著者通过深入浅出的语言、生动形象的图解、严密深邃的辩证逻辑和极为简洁的数学表述,对高分子非线性流变学中的基本概念和模型(例如:屈服、有限内聚力和解缠结等),以及高分子非线性流变学中的典型现象(例如:应力过冲、非静态松弛、剪切带和应变硬化等),进行了系统地分析与探索.在我国推介此书,对年轻学者快速了解该领域的前沿工作有重要的指导作用,即使对从事本领域研究的学者,在启发创新思维和提高品判能力方面仍有相当的帮助.  相似文献   

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