The alkaline hydrolysis of 4-Nitrophenyl acetate was studied at 30℃±0.1℃ in the micellar solutions of three surfactants(Brij35,CTAB and SDS).Based on the psedrophase model of micellar catalysis of Menger and Po...The alkaline hydrolysis of 4-Nitrophenyl acetate was studied at 30℃±0.1℃ in the micellar solutions of three surfactants(Brij35,CTAB and SDS).Based on the psedrophase model of micellar catalysis of Menger and Portnoy,the kinetic equations of micellar catalysis were derived.The results indicated that CTAB micellar system effectively catalyzed the hydrolysis of carboxylic ester,compared with Brij35 and SDS micallar systems under the same reaction conditions.Kψ and km of PNPA hydrolysis increase with the rising in the concentration of NaOH reaction system.Furthermore,the chemical kinetic parameters k1m and k2m in the micellar psedrophase and association constant reactant with micellar KS were calculated with the kinetic equations of micellar catalysis.展开更多
A study was made of magnetic field effects (MFEs) on the photoreduction reaction of 2-methyl-1,4-naphthoqui- none (MNQ) in Brij 35 micellar solution containing 4-lauroylamino-TEMPO (2,2,6,6-tetramethylpiperidine-1-oxy...A study was made of magnetic field effects (MFEs) on the photoreduction reaction of 2-methyl-1,4-naphthoqui- none (MNQ) in Brij 35 micellar solution containing 4-lauroylamino-TEMPO (2,2,6,6-tetramethylpiperidine-1-oxyl) radical (L-R) under magnetic fields below 1.75 T by a nanosecond laser flash photolysis technique. The triplet MNQ mainly underwent the hydrogen abstraction from Brij 35 molecule to give a radical pair. The escaped radical yield increased with magnetic fields from 0 to 0.62 T and then saturated from 0.62 to 1.75 T. MFEs for both sys-tems can be explained by the relaxation mechanism. However, it was supposed that additional radical, L-R affected the MFEs mainly through enhancing the spin-spin interactions of radical pairs. The effect of the micelle size on MFEs of the studying system was also discussed.展开更多
文摘The alkaline hydrolysis of 4-Nitrophenyl acetate was studied at 30℃±0.1℃ in the micellar solutions of three surfactants(Brij35,CTAB and SDS).Based on the psedrophase model of micellar catalysis of Menger and Portnoy,the kinetic equations of micellar catalysis were derived.The results indicated that CTAB micellar system effectively catalyzed the hydrolysis of carboxylic ester,compared with Brij35 and SDS micallar systems under the same reaction conditions.Kψ and km of PNPA hydrolysis increase with the rising in the concentration of NaOH reaction system.Furthermore,the chemical kinetic parameters k1m and k2m in the micellar psedrophase and association constant reactant with micellar KS were calculated with the kinetic equations of micellar catalysis.
基金Project supported by the Scientific Research Foundation for the Returned Overseas Chinese Scholars State Education Ministry+1 种基金 and the Scientific Research Foundation for the Returned Overseas University of Science and Technology of China (No. 2047308
文摘A study was made of magnetic field effects (MFEs) on the photoreduction reaction of 2-methyl-1,4-naphthoqui- none (MNQ) in Brij 35 micellar solution containing 4-lauroylamino-TEMPO (2,2,6,6-tetramethylpiperidine-1-oxyl) radical (L-R) under magnetic fields below 1.75 T by a nanosecond laser flash photolysis technique. The triplet MNQ mainly underwent the hydrogen abstraction from Brij 35 molecule to give a radical pair. The escaped radical yield increased with magnetic fields from 0 to 0.62 T and then saturated from 0.62 to 1.75 T. MFEs for both sys-tems can be explained by the relaxation mechanism. However, it was supposed that additional radical, L-R affected the MFEs mainly through enhancing the spin-spin interactions of radical pairs. The effect of the micelle size on MFEs of the studying system was also discussed.
