Various experimental conditions were described for the vanadium determinationby graphite furnace atomic absorption spectroscopy (GFAAS). The experiments showed that whenatomization took place under the conditions wher...Various experimental conditions were described for the vanadium determinationby graphite furnace atomic absorption spectroscopy (GFAAS). The experiments showed that whenatomization took place under the conditions where the combination of a pyrolytic coating graphitetube and fast raising temperature were used and the temperature was stable, the signal peak shapescould be improved, the sensitivity was enhanced, and the memory effect was removed. The vanadium infood and traditional Chinese medicinal herbs can be accurately determined using the standard curvemethod.展开更多
The mechanism of the atomization of boron and the enhancement of sensitivity by matrix modifier Sr(NO_3)_2 in graphite furnace AAS were discussed.X-ray diffraction and thermodynamic calculation were applied to study t...The mechanism of the atomization of boron and the enhancement of sensitivity by matrix modifier Sr(NO_3)_2 in graphite furnace AAS were discussed.X-ray diffraction and thermodynamic calculation were applied to study the mechanism of boron atomization with and without matrix mo- difier Sr(NO_3)_2.The formation of boron atom is due to the sublimation of solid boron which derived from the reduction of B_2O_3 by carbon.The enhancement of boron signal in the presence of Sr(NO_3)_2 is due to the formation of SrB_6 before atomization,which decreased the volatization losses of B_2O_3 and retarded the formation of B_4C.展开更多
The adsorption properties of nanometer-size TiO2 for V（Ⅴ ） were studied. The adsorption rate could reach above 99~ when the pH values were at the range of 4 10. The adsorption balance time was 10 min , the saturati...The adsorption properties of nanometer-size TiO2 for V（Ⅴ ） were studied. The adsorption rate could reach above 99~ when the pH values were at the range of 4 10. The adsorption balance time was 10 min , the saturation capacity of adsorption of nanometer-size TiO2 to V（Ⅴ） was 6.43 mg per gram. Using 2 mL 1.5 mol · L^-1 NaOH as elution, we found the elution rate could reach 95%. A novel method of extreme-trace V（Ⅴ ） preconeentration with nanometer-size titanium dioxide and determination by graphite furnace atomic absorption spectroscopy （GFAAS） was advanced. The detection limit（3σ）of the method was 0.61μg ·L^-1 , and the relative standard deviation was 8.1% （n=6） of 2.5μg ·L-^1 V（Ⅴ）. Environmental samples experiments were also conducted to test the feasibility of the method, and it came out that the recovery rates were between 91.2% and 102.0%.展开更多
文摘Various experimental conditions were described for the vanadium determinationby graphite furnace atomic absorption spectroscopy (GFAAS). The experiments showed that whenatomization took place under the conditions where the combination of a pyrolytic coating graphitetube and fast raising temperature were used and the temperature was stable, the signal peak shapescould be improved, the sensitivity was enhanced, and the memory effect was removed. The vanadium infood and traditional Chinese medicinal herbs can be accurately determined using the standard curvemethod.
文摘The mechanism of the atomization of boron and the enhancement of sensitivity by matrix modifier Sr(NO_3)_2 in graphite furnace AAS were discussed.X-ray diffraction and thermodynamic calculation were applied to study the mechanism of boron atomization with and without matrix mo- difier Sr(NO_3)_2.The formation of boron atom is due to the sublimation of solid boron which derived from the reduction of B_2O_3 by carbon.The enhancement of boron signal in the presence of Sr(NO_3)_2 is due to the formation of SrB_6 before atomization,which decreased the volatization losses of B_2O_3 and retarded the formation of B_4C.
文摘The adsorption properties of nanometer-size TiO2 for V（Ⅴ ） were studied. The adsorption rate could reach above 99~ when the pH values were at the range of 4 10. The adsorption balance time was 10 min , the saturation capacity of adsorption of nanometer-size TiO2 to V（Ⅴ） was 6.43 mg per gram. Using 2 mL 1.5 mol · L^-1 NaOH as elution, we found the elution rate could reach 95%. A novel method of extreme-trace V（Ⅴ ） preconeentration with nanometer-size titanium dioxide and determination by graphite furnace atomic absorption spectroscopy （GFAAS） was advanced. The detection limit（3σ）of the method was 0.61μg ·L^-1 , and the relative standard deviation was 8.1% （n=6） of 2.5μg ·L-^1 V（Ⅴ）. Environmental samples experiments were also conducted to test the feasibility of the method, and it came out that the recovery rates were between 91.2% and 102.0%.
