Papers by Author: Gang Xu

Abstract: Hydrargyrum(Hg) and arsenic(As) in tap water of Chongqing University Town were detected by the X-atomic fluorescence spectrometry, and the United States Environmental Protection Agency (USEPA)-supported Health Risk Assessment Model was used for evaluating the potential health risk to surrounding residents caused by Hg and As in tap water. The results showed that the average concentration of Hg and As in tap water of this region were 0.6323μg/L and 20.1237μg/L respectively, wherein the Hg content was lower than the national Standards for Drinking Quality (GB5749-2006), but the As content exceeded its stipulated level, the annual personal risk level of health hazard caused by Hg and As by the way of drinking water were 2.840×10^-8•a^-l and 1.350×10^-4•a^-l, wherein Hg would not cause apparent harm to exposure population, while As was higher than the maximum acceptable risk level by the way of drinking water（5×10^-5•a^-l）recommended by the International Committee on Radiological Protection (ICRP).

Abstract: A new highly selective poly vinyl chloride (PVC) membrane thiocyanate (SCN–) electrode of copper (II) complex with ethylene-diamine-bis-(salicylaldehyde) [Cu (II)-SALEN] base with neutral carrier was studied, it displays a preferential potentiometric response to SCN– . The electrode exhibited near Nernst potential response to SCN– with a concentration range of 1.0×10-1～1.0×10-7 mol/L, a slope of －46 mV/p SCN– and a detection limit of 3.5×10-8 mol/L in pH5.5 of phosphate buffer solution at 25°C. PVC membrane electrode based on Cu (II)-SALEN had good selectivity to SCN– and some common anions had little interference with it. This electrode was applied to the determination of SCN– in waste water and the result obtained were in good agreement with those of high performance liquid chromatography (HPLC) method.