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A series of visible-light-driven mesoporous structured MnO(2)/TiO(2) nanocrystal photocatalysts have been synthesized through a modified sol-gel method, and the N(2) adsorption-desorption isotherm confirms that the mesoporous materials possess large pore size (up to 9.2 nm) and a narrow pore size distribution. X-ray powder diffraction (XRD) analyses and complementary x-ray photoelectron spectroscopy (XPS) measurements reveal that the doping of the transition metal Mn inhibits the growth of TiO(2) anatase nanocrystals and the Mn species are highly dispersed on the surface of TiO(2). The ultraviolet (UV)-vis spectrum demonstrates the excellent adsorption properties of MnO(2)/TiO(2) over the whole region of visible light, which enables this novel photocatalysis material to possess remarkable activity in the photocatalytic degradation of methylene blue under visible light radiation. Moreover, a 'coating mechanism' based on the nucleation of titania nanocrystals along with the interaction between the dopant precursors and titania clusters has been suggested.

This study investigated the distribution and identification of chlorides in distillates from YS crude oil on the basis of true boiling point (TBP) distillation technology. YS crude oil was categorized into low-acid light crude oil with total chlorine content of 10.019 mg/l, in which the inorganic chlorine and organochlorine contents were determined as 5.870 and 4.419 mg/l, respectively. A total of 21 distillates and one residual oil (>500 °C) were obtained by TBP distillation. The organochlorine compounds were observed as predominant one among all distillates instead of inorganic chlorine compounds. The organochlorine content of 141.1 mg/l within the boiling range of 39.2 °C (initial boiling point, IBP) to 60 °C was the maximum when compared with that in other distillates. However, the organochlorine content in distillates gradually decreased with increasing boiling range from IBP to 260 °C. Meanwhile, low-boiling chlorides, such as carbon tetrachloride and trichloroethylene, were identified from the distillates (<300 °C) via gas chromatography with electron capture detector (ECD). Accordingly, these low-boiling chlorides coexisted in almost all distillates (<300 °C). By contrast, high boiling components with electronegativity were observed only in the boiling range of 220 °C to 300 °C, and these species increased with the increasing boiling range of distillates.

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