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TiO2/tourmaline composite photocatalyst was prepared by sol-gel method using tetrabutyl orthotitanate (Ti (OC4H9)4) as a precursor. As a comparison, pure TiO2 was prepared at the same experimental conditons without the addition of tourmaline. The obtained composite photocatalyst was characterized by X-Ray diffraction (XRD) and scanning electron microscope (SEM) and its photocatalytic activity was also investigated through the photodiscoloration of methyl orange (MO) under UV irradiation. The XRD results indicated that, in the composite photocatalyst, TiO2 existed in the form of anatase and rutile, with the sintering temperature and tourmaline content increasing, the anatase phase trended to the transformation to rutile phase. The SEM results revealed that the nanosized particles of TiO2 were well dispersed and immobilized on the surface of tourmaline, especially for the sample with 2% tourmaline content. Compared with pure TiO2, the composite photocatalyst exhibited a higher photocatalytic activity. When the pure TiO2 was used as the photocatalyst, the MO discoloration ratio only reached 55%. However, the MO discoloration ratio could approach 100% in presence of TiO2/tourmaline composit photocatalyst under the same conditions. The effects of tourmaline content and sintering temperature on the photocatalytic activity of the composite were studied in this work and the results suggested that the sample with 2% tourmaline content and sintered at the temperature of 550oC exhibited the best photocatalytic activity. Finally, the possible mechanism for the photodiscoloration of MO was put forward.

Flow units are divided into E,G and P types for the Lower S2 reservoir of Wen-X fault block in the Wenliu Oilfield, which are identificated based on six parameters including porosity, permeability, sandstone thickness, effective thickness, formation conductivity and flow index. A 3-D model for the flow units is established by sequential gaussian stochastic simulation approach. It is believed that type- E flow units are well exploited, with the distribution of the remaining oils related to fault as a barrier；type-G flow units are less exploited, with enrichment of remaining oil, due to the influence of interlayer or lateral heterogeneity；and type-P flow units are difficult to be exploited because of the poor percolation and a lower reserves abundance

The decoloration of methyl orange (MO) dyeing wastewater by mineral-catalyzed Fenton-like system of schorl and H2O2 was conducted in this study. The experimental results showed that schorl could efficiently make MO decolor in the presence of H2O2. Through a number of batch decoloration experiments under various conditions, it was found that the MO decoloration ratios increased by increasing the reaction temperature and the optimum addition of schorl and H2O2 was 1g and 1mL, respectively. At pH=2, a maximum of MO decoloration ratio could reach 99%. About 99.61% of MO decoloration ratio could be achieved in presence of schorl and H2O2, which was much higher than that in presence of schorl or H2O2 only, with MO decoloration ratio of 60.88% and 52.8, respectively, which suggested the schorl-catalyzed Fenton-like reaction governed the MO decoloration process. Otherwise, the MO decoloration ratio could be enhanced under the condition of agitation or UV-irradiation. The decoloration mechanism analysis revealed that the MO decoloration process was governed by a mineral-catalyzed Fenton-like reaction. Fe2+/Fe3+dissolved from the surface of schorl catalyzed the decomposition of H2O2 to produce OH radical, which then oxidized the MO.