Papers by Author: Ling Yan Ren

Abstract: A new highly selective poly vinyl chloride(PVC) membrane iodide electrode which has neutral carrier of cobalt(Ⅱ) complex with symmetrical binuclear schiff base has been studied. Based on the fact we knew that ethylenediamine could react to acetylacetone and salicylaldehyde. The electrode exhibited near -Nernst response to iodide with a slope of ―54.4 mV/dec over a wide concentration range (1.58×10^-7~1.0×10^-1 mol/L) with a detection limit of 6.3×10^-8 mol/L in phosphorate bufer solution with pH=2.4 at 26°C. After applied to the determination of iodide in pharmaceuticals and salts, the electrode could get satisfied results

Abstract: The paper adopted Coagulation-Fenton Oxidation Method on treating the wastewater of 6-nitro-1,2 diazonium oxygroup naphthalene-4-sulfoacid production process (i.e. 6-nitry wastewater), introduced the treatment effect of the combined technology used on 6-nitry wastewater, and studied the factors influencing the treatment effect, to determine the reasonable parameters of the technology on treating 6-nitry wastewater. The results showed that Using polyaluminium chloride (mass fraction 2%) as flocculant for treating 6-nitry wastewater, the COD removal rate reached up to 48.7%; Making Fenton reagent oxidation treatment on coagulation yielding water, under the best conditions for solution acidity controlled at pH3 or so, in the 100 mL wastewater, 30% hydrogen peroxide was 5.0 mL, 0.5 mol/L ferrous sulfate solution was 4.0 mL, reaction time was 60 min, the COD removal rate could reach 98% or more.

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.