A simple and sensitive spectrophotometric method was described for the determination of cerium（IV） based on its catalytic effect on the oxidation of naphthol green B by potassium periodate in the medium of sulfuric ...A simple and sensitive spectrophotometric method was described for the determination of cerium（IV） based on its catalytic effect on the oxidation of naphthol green B by potassium periodate in the medium of sulfuric acid. The influences of acidity, concentration of reactants, reaction time, reaction temperature, and foreign ions were discussed, and the optimum reaction conditions were established. The reaction was monitored spectrophotometrieally by measuring the decrease in absorbance of naphthol green B at 710 nm after a fixed time （8 min）. The proposed method allowed the determination of cerium（IV） in the range of 0.08-2.4 μg·mL^-1 with good precision and accuracy, and the detection limit was 0.012 μg·mL^-1. The method was applied successfully for the determination of trace cerium in hair samples without previous separation. Recovery experiments were also performed, and the recovery was between 95.7%-111.0%.展开更多
This paper was focused on the determination of trace vanadium(V)by catalytic kinetic spectrophotometric method.In this method,the vanadium(V)can catalyze the fading reaction that potassium periodate acted on malachite...This paper was focused on the determination of trace vanadium(V)by catalytic kinetic spectrophotometric method.In this method,the vanadium(V)can catalyze the fading reaction that potassium periodate acted on malachite green.Best experimental conditions were studied and a new method of catalytic kinetic spectrophotometric determination of vanadium(V)was established.Under selected experimental conditions,the absorbency difference △A remained good linear relationship with quality concentration ρ of vanadium(V)in the range of 0.1–1.5 ug/25 mL and the detection limit was 7.87×10-10 g/mL.Dynamic parameters were determined and showed that the reaction was pseudo first-order kinetics equation.Apparent ratio constant of the reaction was 7.39×10-4 /s and apparent active energy was 63.60 kJ/mol.RSD of 12 times determination of 1 μg V(Ⅴ)/25 mL standard solution was 1.25%.In the determination of trace Vanadium(V)in sinter I and sinter III,the recovery ratio was between 97.6–107.6%.The experiment result was satisfactory.展开更多
基金supported by the Natural Sci-ence Foundation of Shandong Province, China (No. Y2008B26)
文摘A simple and sensitive spectrophotometric method was described for the determination of cerium（IV） based on its catalytic effect on the oxidation of naphthol green B by potassium periodate in the medium of sulfuric acid. The influences of acidity, concentration of reactants, reaction time, reaction temperature, and foreign ions were discussed, and the optimum reaction conditions were established. The reaction was monitored spectrophotometrieally by measuring the decrease in absorbance of naphthol green B at 710 nm after a fixed time （8 min）. The proposed method allowed the determination of cerium（IV） in the range of 0.08-2.4 μg·mL^-1 with good precision and accuracy, and the detection limit was 0.012 μg·mL^-1. The method was applied successfully for the determination of trace cerium in hair samples without previous separation. Recovery experiments were also performed, and the recovery was between 95.7%-111.0%.
文摘This paper was focused on the determination of trace vanadium(V)by catalytic kinetic spectrophotometric method.In this method,the vanadium(V)can catalyze the fading reaction that potassium periodate acted on malachite green.Best experimental conditions were studied and a new method of catalytic kinetic spectrophotometric determination of vanadium(V)was established.Under selected experimental conditions,the absorbency difference △A remained good linear relationship with quality concentration ρ of vanadium(V)in the range of 0.1–1.5 ug/25 mL and the detection limit was 7.87×10-10 g/mL.Dynamic parameters were determined and showed that the reaction was pseudo first-order kinetics equation.Apparent ratio constant of the reaction was 7.39×10-4 /s and apparent active energy was 63.60 kJ/mol.RSD of 12 times determination of 1 μg V(Ⅴ)/25 mL standard solution was 1.25%.In the determination of trace Vanadium(V)in sinter I and sinter III,the recovery ratio was between 97.6–107.6%.The experiment result was satisfactory.
