The photodegradation mechanism of fenvalerate in water has been investigated by density functional theory（DFT）.The geometries of reactants,transition states,intermediates and products are optimized at the B3LYP/6-31...The photodegradation mechanism of fenvalerate in water has been investigated by density functional theory（DFT）.The geometries of reactants,transition states,intermediates and products are optimized at the B3LYP/6-31G＊ level.The calculated results indicate that the reaction process mainly includes the nucleophilic attack and the substitution reaction by hydroxyl radical to the carbonyl group.By vibrational frequency analysis and intrinsic reaction coordinate（IRC） method,the transition state and its reaction pathway are confirmed.Moreover,the changes of natural population analysis（NPA）,calculated using the Natural bond orbital（NBO） method,are analyzed along with the degradation reaction which can explain the variation of chemical bonds.Additionally,the solvent effect is also investigated and the results show that the reaction preferably takes place in water.展开更多
Three novel chiral selectors 4a-c were synthesized from （S）-amino acids and （R）-1-phenyl-2-（4-methylphenyl）ethylamine. 4a-c were connected to 3-aminopropylsilanized silica gel to be used as the chiral stationary...Three novel chiral selectors 4a-c were synthesized from （S）-amino acids and （R）-1-phenyl-2-（4-methylphenyl）ethylamine. 4a-c were connected to 3-aminopropylsilanized silica gel to be used as the chiral stationary phase for HPLC. Five amino acid derivatives and two pyrethroid insecticides were fairly resolved on these three new chiral stationary phases under normal phase condition.展开更多
Objective To study the metabolism of 14^C-deltamethrin in rats. Methods Rats were dosed orally and i.p. with a single dose of 14^C-deltamethrin （0.64 mg/Kg） body weight. The required dose was applied daily for 3 day...Objective To study the metabolism of 14^C-deltamethrin in rats. Methods Rats were dosed orally and i.p. with a single dose of 14^C-deltamethrin （0.64 mg/Kg） body weight. The required dose was applied daily for 3 days. At the end of the experiment, selected organs, such as liver, kidney, fat, intestine, and blood were excised for radioassay of 14^C-content. Results Deltamethrin was almost eliminated from the body within 1-3 days. The main portion of 14^C-residues was extracted from urine （38%, 32%） and feces （20%, 24%） with a little amount remained in various organs. Conclusion The elimination and distribution of 14^C-radioactivity in rats treated orally and intraperitoneally signify that deltamethrin is bioavallable in urine and feces.展开更多
基金supported by the National Natural Science Foundation of China (Nos.40976041 and 20775074)
文摘The photodegradation mechanism of fenvalerate in water has been investigated by density functional theory（DFT）.The geometries of reactants,transition states,intermediates and products are optimized at the B3LYP/6-31G＊ level.The calculated results indicate that the reaction process mainly includes the nucleophilic attack and the substitution reaction by hydroxyl radical to the carbonyl group.By vibrational frequency analysis and intrinsic reaction coordinate（IRC） method,the transition state and its reaction pathway are confirmed.Moreover,the changes of natural population analysis（NPA）,calculated using the Natural bond orbital（NBO） method,are analyzed along with the degradation reaction which can explain the variation of chemical bonds.Additionally,the solvent effect is also investigated and the results show that the reaction preferably takes place in water.
基金the National Natural Science Foundation of China （No. 20472111） is gratefully acknowledged.
文摘Three novel chiral selectors 4a-c were synthesized from （S）-amino acids and （R）-1-phenyl-2-（4-methylphenyl）ethylamine. 4a-c were connected to 3-aminopropylsilanized silica gel to be used as the chiral stationary phase for HPLC. Five amino acid derivatives and two pyrethroid insecticides were fairly resolved on these three new chiral stationary phases under normal phase condition.
文摘Objective To study the metabolism of 14^C-deltamethrin in rats. Methods Rats were dosed orally and i.p. with a single dose of 14^C-deltamethrin （0.64 mg/Kg） body weight. The required dose was applied daily for 3 days. At the end of the experiment, selected organs, such as liver, kidney, fat, intestine, and blood were excised for radioassay of 14^C-content. Results Deltamethrin was almost eliminated from the body within 1-3 days. The main portion of 14^C-residues was extracted from urine （38%, 32%） and feces （20%, 24%） with a little amount remained in various organs. Conclusion The elimination and distribution of 14^C-radioactivity in rats treated orally and intraperitoneally signify that deltamethrin is bioavallable in urine and feces.
