A novel thermal-assisted ultra-violet(UV) photocatalysis digestion method for the determination of total phosphorus(TP) in water samples was introduced in this work. The photocatalytic experiments for TP digestion wer...A novel thermal-assisted ultra-violet(UV) photocatalysis digestion method for the determination of total phosphorus(TP) in water samples was introduced in this work. The photocatalytic experiments for TP digestion were conducted using a 365 nm wavelength UV light and Ti O2 particles as the photocatalyst. Sodium tripolyphosphate and sodium glycerophosphate were used as the typical components of TP and the digested samples were then determined by spectrophotometry after phosphomolybdenum blue reaction. The effects of operational parameters such as reaction time and temperature were studied for the digestion of TP and the kinetic analysis of two typical components was performed in this paper. The pseudo-first-order rate constants k of two phosphorus compounds at different temperatures were obtained and the Arrhenius equation was employed to explain the effect of temperature on rate constant k. Compared with the conventional thermal digestion method for TP detection, it was found that the temperature was decreased from 120 °C to 60 °C with same conversion rate and time in this thermal-assisted UV digestion method, which enabled the digestion process work at normal pressure. Compared with the individual ultra-violet(UV) photocatalysis process, the digestion time was also decreased from several hours to half an hour using the thermal-assisted UV digestion method. This method will not lead to secondary pollution since no oxidant was needed in the thermal-assisted UV photocatalysis digestion process, which made it more compatible with electrochemical detection of TP.展开更多
An efficient and practical method is developed for the trifluoromethylation of enamides using Umemoto's reagent as the trifluoromethylating reagent. These reactions proceeded under visible light irradiation withou...An efficient and practical method is developed for the trifluoromethylation of enamides using Umemoto's reagent as the trifluoromethylating reagent. These reactions proceeded under visible light irradiation without any photocatalyst at room temperature in good chemical yields.展开更多
基金Supported by the National Natural Science Foundation(61372053)the National High Technology Research and Development Program(2012AA040506)
文摘A novel thermal-assisted ultra-violet(UV) photocatalysis digestion method for the determination of total phosphorus(TP) in water samples was introduced in this work. The photocatalytic experiments for TP digestion were conducted using a 365 nm wavelength UV light and Ti O2 particles as the photocatalyst. Sodium tripolyphosphate and sodium glycerophosphate were used as the typical components of TP and the digested samples were then determined by spectrophotometry after phosphomolybdenum blue reaction. The effects of operational parameters such as reaction time and temperature were studied for the digestion of TP and the kinetic analysis of two typical components was performed in this paper. The pseudo-first-order rate constants k of two phosphorus compounds at different temperatures were obtained and the Arrhenius equation was employed to explain the effect of temperature on rate constant k. Compared with the conventional thermal digestion method for TP detection, it was found that the temperature was decreased from 120 °C to 60 °C with same conversion rate and time in this thermal-assisted UV digestion method, which enabled the digestion process work at normal pressure. Compared with the individual ultra-violet(UV) photocatalysis process, the digestion time was also decreased from several hours to half an hour using the thermal-assisted UV digestion method. This method will not lead to secondary pollution since no oxidant was needed in the thermal-assisted UV photocatalysis digestion process, which made it more compatible with electrochemical detection of TP.
基金supported by the National Natural Science Foundation of China(2147208481421091)+2 种基金the Qing Lan Project of Jiangsu Province and State Key Laboratory of Bioorganic & Natural Products ChemistryShanghai Institute of Organic ChemistryChinese Academy of Sciences
文摘An efficient and practical method is developed for the trifluoromethylation of enamides using Umemoto's reagent as the trifluoromethylating reagent. These reactions proceeded under visible light irradiation without any photocatalyst at room temperature in good chemical yields.
