A new highly selective thiocyanate PVC membrane electrode based on bisbebzoin-semitriethylenetetraamine binuclear cobalt(Ⅱ) metallic complex [Co(Ⅱ) 2-BBSTA] as neutral carrier is reported, which displays an anti-Hof...A new highly selective thiocyanate PVC membrane electrode based on bisbebzoin-semitriethylenetetraamine binuclear cobalt(Ⅱ) metallic complex [Co(Ⅱ) 2-BBSTA] as neutral carrier is reported, which displays an anti-Hofmeister selectivity sequence. The electrode exhibits Nernstian potential linear range to thiocyanate from 1.0×10 -1 to 1.0×10 -6 mol/L with a detection limit 8.0×10 -7 mol/L and a slope of -52.0 mV/dec in phosphorate buffer solution of pH=5.0 at 25 ℃. The response mechanism is discussed in view of the a.c. impedance technique and the UV spectroscopy technique. The electrode based on binuclear cobalt(Ⅱ) compound was used to determine the thiocyanate content in waste water with satisfactory results.展开更多
In a thin HCl medium,RRS intensities of an alone CS or acidic triphenylmethane dye (TPMD) are very week. However,when TPMD reacts with a CS to form an ion-associate,the RRS intensity is enhanced greatly and a new RRS ...In a thin HCl medium,RRS intensities of an alone CS or acidic triphenylmethane dye (TPMD) are very week. However,when TPMD reacts with a CS to form an ion-associate,the RRS intensity is enhanced greatly and a new RRS spectrum appears. The spectral characteristics of the RRS for the ion-associates and the optimum conditions for the reactions are investigated. The intensity of RRS is directly proportional to the mass concentration of CS in the range of 0—3.5 or 0—5.0 μg/mL. The method has a high sensitivity for the determination of CS,their detection limits are between 3.1 and 9.8 ng/mL depending on the different CS. In this case,most metal and non-metal ions do not interfere,so that the method has a good selectivity. Therefore,a sensitive,selective,simple and rapid method for the determination of CS by RRS is developed. [WT5HZ]展开更多
文摘A new highly selective thiocyanate PVC membrane electrode based on bisbebzoin-semitriethylenetetraamine binuclear cobalt(Ⅱ) metallic complex [Co(Ⅱ) 2-BBSTA] as neutral carrier is reported, which displays an anti-Hofmeister selectivity sequence. The electrode exhibits Nernstian potential linear range to thiocyanate from 1.0×10 -1 to 1.0×10 -6 mol/L with a detection limit 8.0×10 -7 mol/L and a slope of -52.0 mV/dec in phosphorate buffer solution of pH=5.0 at 25 ℃. The response mechanism is discussed in view of the a.c. impedance technique and the UV spectroscopy technique. The electrode based on binuclear cobalt(Ⅱ) compound was used to determine the thiocyanate content in waste water with satisfactory results.
文摘In a thin HCl medium,RRS intensities of an alone CS or acidic triphenylmethane dye (TPMD) are very week. However,when TPMD reacts with a CS to form an ion-associate,the RRS intensity is enhanced greatly and a new RRS spectrum appears. The spectral characteristics of the RRS for the ion-associates and the optimum conditions for the reactions are investigated. The intensity of RRS is directly proportional to the mass concentration of CS in the range of 0—3.5 or 0—5.0 μg/mL. The method has a high sensitivity for the determination of CS,their detection limits are between 3.1 and 9.8 ng/mL depending on the different CS. In this case,most metal and non-metal ions do not interfere,so that the method has a good selectivity. Therefore,a sensitive,selective,simple and rapid method for the determination of CS by RRS is developed. [WT5HZ]