A dye-sensitized visible light photocatalyst-Bi24 O31 Cl10

The p-block semiconductors are regarded as a new family of visible-light photocatalysts because of their dispersive and anisotropic band structures as well as high chemical stability. The bismuth oxide halides belong to this family and have band structures and dispersion relations that can be engineered by modulating the stoichiometry of the halogen elements. Herein, we have developed a new visible-light photocatalyst Bi 24 O 31 Cl 10 by band engineering, which shows high dye-sensitized photocatalytic activity. Density functional theory calculations reveal that the p-block elements determine the nature of the dispersive electronic structures and narrow band gap in Bi 24 O 31 Cl 10. Bi 24 O 31 Cl 10 exhibits excellent visible-light photocatalytic activity towards the degradation of Rhodamine B, which is promoted by dye sensitization due to compatible energy levels and high electronic mobility. In addition, Bi 24 O 31 Cl 10 is also a suitable photoanode material for dye-sensitized solar cells and shows power conversion efficiency of 1.5%.

地球化学场的多重分形分析与分解

Geochemical and Geophysical anomaly play an important role in mineral exploration，their spatial structure character include singularity and self－similar。The singularity of an anomaly reflects the enrichment characters of the geochemical element ,The anomaly separation by multifractal model is useful in mineral anomaly assessment。In recent years, The continuous multifractal mode of the geochemical fields was studied ,it can be separated into the simple continuous multifractal mode and the high concentration multifractal mode, and the C－A、C－D、 S－A、MSDV、W－A method to decompose the anomaly were presented。Those are succeeded in interpretation of Geochemical and Geophysical anomaly。 This study makes a summarization to these method， we present a multifractal method based on wavelet transform to analyze the multifractal fields 。The singularity and spectrum are calculated through tracing the wavelet maximum modulus in different measure，and then the fields can be decomposed by the characters of the singularity。 It is demonstrated to be useful in interpretation of Au anomaly in Gekou－Shicheng region Rushang Shandong Province 。 Based on the multifractal theory , Using the concentration—area（C—A）method ,We study two geochemical fields in Chifeng area , Inner Mongolia。The results show that the geochemical fields have three different multifractal modes。Based on these ,we discuss the enrichment mode of the geochemical elements and their distributions in space and get the anomaly lower limit ,then the geochemical backgrounds、regional anomalies and local anomalies are distinguished

Chemistry and fluid inclusions of the sheeted dike comples of ODP Holes 137-504B and 140-504B

Fluid inclusions in variably altered diabase recovered from Ocean Drilling Program Legs 137 and 140 at Hole 504B, Costa Rica Rift, exhibit fluid salinities up to 3.7 times that of seawater values (11.7 wt% NaCl equivalent) and exhibit uncorrected homogenization temperatures of 125°C to 202°C. The liquid-dominated inclusions commonly are entrapped in zones of secondary plagioclase and may be primary in origin. Fluid salinities are similar to compositions of fluids venting on the seafloor (0.4-7.0 wt% NaCl) and overlap with those measured in metabasalt samples recovered from near the Kane Fracture Zone on the Mid-Atlantic Ridge and from the Troodos ophiolite, Cyprus. The salinity variations may reflect hydration reactions involving formation of secondary mineral assemblages under rock-dominated conditions, which modify the ionic strength of hydrothermal fluids by consuming or liberating water and chloride ion. Rare CO2-CH4-bearing inclusions, subjacent to zones where talc after olivine becomes an important secondary mineral phase (1700 mbsf), may have formed due to local interaction of seawater and olivine at low water to rock ratios. Corrected average fluid inclusion homogenization temperatures exhibit a gradient from 159°C at a depth of 1370 mbsf to 183°C at a depth of 1992 mbsf and are in apparent equilibrium with the present conductive downhole temperatures. These data indicate that fluid inclusions may be used to estimate downhole temperatures if logging data are unavailable. The compositional and thermal evolution of the diabase-hosted fluids may reflect late-stage, off-axis circulation and conductive heating of compositionally modified seawater in the sheeted dike complex at Hole 504B.