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Bi-based oxyhalide Bi4TaO8X (X=Cl, Br, I) photocatalysts have been prepared by the combined method of liquid phase and solid state reactions and characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and Ultraviolet-visible diffuse reflectance spectroscopy (UV-vis DRS). Using the azo dye wastewater simulated by aqueous methyl orange (MO) solutions, photocatalytic activity of these catalysts was studied under ultraviolet light, visual light, and solar irradiation. All of the samples had high photocatalytic activity. After 2 h of ultraviolet radiation, the degradation efficiency of methyl orange by Bi4TaO8X (X=Cl, Br, I) was as high as 100%. Under visible-light and solar irradiation, the photocatalytic activity decreased in the order Bi4TaO8I>Bi4TaO8Br>Bi4TaO8Cl. More than 90% degradation efficiency was observed for Bi4TaO8I after 12 h of solar irradiation. Furthermore, the photocatalytic degradation kinetics of methyl orange have been investigated under different types of light irradiation. [ABSTRACT FROM AUTHOR]

Abstract: In this work, a novel Bi-based oxyhalide Bi4TaO8I was prepared and characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and UV–vis diffuse reflectance spectroscopy. Photocatalytic activity of this material was evaluated by using methyl orange (MO) as a representative azo dye. It was found that Bi4TaO8I had a visible light absorption, and the band-gap energy was estimated to be 2.43eV. This material exhibited good photocatalytic activity under both ultraviolet and visible light irradiation. The effects of initial MO concentration, aqueous pH, catalyst dosage and irradiation time on the photocatalytic activity were studied systematically. The photocatalytic degradation of MO by Bi4TaO8I under visible-light irradiation was found to follow the pseudo first-order reaction at the low initial concentrations of MO. Reuse of the catalyst was also examined, and the degradation efficiency of MO was still as high as 60% after 3cycles of 28h visible-light irradiation. Furthermore, it was found that the degradation of MO was also effective under solar irradiation. Five main degradation products were observed by HPLC/MS and their chemical structures were suggested. In order to exclude the photosensitization effect, the photocatalytic degradation efficiency of pentachlorophenol (PCP) by Bi4TaO8I was also determined under visible light irradiation. It is expected that Bi4TaO8I would have potential application in the degradation of azo dye wastewaters under solar irradiation. [Copyright &y& Elsevier]

Objective: To observe the protective effect of Panax notoginseng saponins (PNS) against pathological lesion of cholinergic neuron in rat model with Alzheimer' s disease (AD)., Methods: The AD rat model was established by intra-peritoneal injection of D-galactose combined with excitatory neurotoxin ibotenic acid (IBA) injection into bilateral nbM. The activity and content of choline acetyltransferase (ChAT), the cell morphology and number of cholinergic neuron in brain were determined by immunohistochemistry analysis., Results: PNS could reduce the pathological lesion of cholinergic neuron, including the level of ChAT and number of cholinergic neuron, as compared with those of model group's rats., Conclusion: PNS plays a protective role in pathological lesion of cholinergic neuron in AD rat model.