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A novel technology (co-sputtering oblique angle deposition) was used for fabricating W-doped Bi 2 O 3 films. After further annealing at 500 °C, the surface morphologies and microstructures of the films were characterized by scanning electron microscopy and X-ray diffraction. With increase in the sputtering current of W target in co-sputtering process, the surface morphology of W-doped Bi 2 O 3 films changed significantly. The mechanism of morphology evolution was systematically studied. The optical properties of W-doped Bi 2 O 3 films such as band gap and photocatalytic performance were also investigated. The results indicate that this co-sputtering oblique angle deposition technology is a promising new method for investigating the nanostructures photocatalytic and other performance of doped materials. [ABSTRACT FROM AUTHOR]

The Shuangwang gold deposit (with a gold resource of approximately 70 t Au), hosted in a NW-trending breccia belt, is located in the Fenxian-Taibai fore-arc basin in the West Qinling Orogen of central China. Four stages of ore paragenesis are identified, demonstrating mineral assemblages of ankerite–quartz–albite, quartz–albite–pyrite–ankerite, pyrite–calcite–quartz, and fluorite–dickite–gypsum, respectively. Fluid inclusions hosted in stages I, II, and III hydrothermal minerals yield homogeneous temperatures of 300–463 °C, 220–340 °C and 100–279 °C, with salinities lower than 22.7 wt% NaCl equiv. Trapping pressures estimated from CO 2 –H 2 O fluid inclusions show a gradual decrease from 100–170 MPa (KT8 ore body) to 17–55 MPa (KT2 ore body), corresponding to mineralization depths from 3.8–6.4 km (KT8) to 0.6–2.1 km (KT2). Hydrogen and oxygen isotopic data suggest that the ore-forming fluids evolved from metamorphic water to magmatic water, and lately meteoric water. Sulfur and carbon isotope compositions show that these fluids might have originated from interaction with the host rocks with minor additional magmatic source. Based on geochemical investigations, with combination of regional and ore deposit geology, a possible genetic model with a three-step ore-forming process is proposed. The Devonian Xinghongpu sedimentary rocks are characterized by a relatively high gold content, which might provide the initial gold source. Linear folds and faults formed during Triassic orogenic processes provided the subsequent pathways for ore-forming fluids and suitable space for gold mineralization. Postorogenic magmatic activity induced voluminous hydrothermal fluids that mixed with the basinal fluids and may have started the ore formation process. Over pressure led to hydrofracturing and the subsequent pressure drop promoted fluid boiling, which in turn resulted in abundant gold deposition. Induced by postorogenic magmatic hydrothermal activity, the Shuangwang gold deposit is considered a special type of orogenic gold deposit formed in a compression–extension transition. [ABSTRACT FROM AUTHOR]