X ray photoemission spectra measurements were carried out to elucidate the valence band picture and bonding characters of the two dimensional semiconductor red bronze K,0.33MoO3. The valence band spectrum is similar ...X ray photoemission spectra measurements were carried out to elucidate the valence band picture and bonding characters of the two dimensional semiconductor red bronze K,0.33MoO3. The valence band spectrum is similar to that of measurement of UPS, and in agreement with the molecular orbital model presented by Travaglini.Asymmetric and b,roadening line shape of O-ls means the presence of several inequivalent bonds of oxygen. Mo-3d core-level spectrum reveals that there are two kinds of valence states of molybdenum (Mo+5,Mo+6 ), and that its average valence state is + 5. 42.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X ray photoemission spectra measurements were carried out to elucidate the valence band picture and bonding characters of the two dimensional semiconductor red bronze K,0.33MoO3. The valence band spectrum is similar to that of measurement of UPS, and in agreement with the molecular orbital model presented by Travaglini.Asymmetric and b,roadening line shape of O-ls means the presence of several inequivalent bonds of oxygen. Mo-3d core-level spectrum reveals that there are two kinds of valence states of molybdenum (Mo+5,Mo+6 ), and that its average valence state is + 5. 42.
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%.
