This paper concerns about the macrosopic kinetics of absorption of sulfur dioxide from dilute gases by sodium sulfide aqueous solution.It has been shown that there are three stages in the process in accordance to the ...This paper concerns about the macrosopic kinetics of absorption of sulfur dioxide from dilute gases by sodium sulfide aqueous solution.It has been shown that there are three stages in the process in accordance to the profile of pH value change.Sulfur dioxide has been fully absorbed in stage I and stage II;stage III is continuously capable of absorption of sulfur dioxide,but the stage is signed by sulfur dioxide detected in the exit gas flows.In addition,the gas film mass transfer controlling ste Pis observed for the absorption of sulfur dioxide in stage I and stage II.The temperature of sodium sulfide aqueous solution negatively influences the overall rate of absorption of sulfur dioxide and the concerntration of sodium sulfide aqueous solution does not influence the overall rate.展开更多
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
Three novel cobalt(Ⅱ) complexes of the benzoaza-15-crown-5 Schiff base were synthesized and characterized.For comparison,the catalytic activity of the complexes were also investigated.The mechanism of the phenol cata...Three novel cobalt(Ⅱ) complexes of the benzoaza-15-crown-5 Schiff base were synthesized and characterized.For comparison,the catalytic activity of the complexes were also investigated.The mechanism of the phenol catalytic oxidation were studied.The acid effect of reaction system,structural effect of the complexes,and effect of temperature on the rate of the phenol catalytic oxidation by the mimetic peroxidase were discussed.The results show:the schiff base cobalt(Ⅱ) complexes as peroxidase mimics exhibit good catalytic activity and similar catalytic character to natural enzyme.展开更多
The title complexes Ni(HDPC)2·3H2O and Cu(DPC)(H2DPC)·2H2O have been synthesized in aqueous solution by the reaction of pyridine-2,6-dicarboxylic(H2DPC) with NiCl2·6H2O and CuCl2·3H2O,respectively....The title complexes Ni(HDPC)2·3H2O and Cu(DPC)(H2DPC)·2H2O have been synthesized in aqueous solution by the reaction of pyridine-2,6-dicarboxylic(H2DPC) with NiCl2·6H2O and CuCl2·3H2O,respectively.The enthalpy change of formation of the reaction on the title complexes in liquid-phase have been determined by a microcalorimeter,respectively. Thermodynamic parameters(the activation enthalpy,the activation entropy and the activation free energy),rate constant and kinetics parameters(the apparent activation energy,the pre-exponential constant and the reaction order) of the title reaction have been calculated.The formation of the two complexes were all exothermic reactions in the range of experimental temperature.The higher reaction velocity was obtained at higher temperature.展开更多
文摘This paper concerns about the macrosopic kinetics of absorption of sulfur dioxide from dilute gases by sodium sulfide aqueous solution.It has been shown that there are three stages in the process in accordance to the profile of pH value change.Sulfur dioxide has been fully absorbed in stage I and stage II;stage III is continuously capable of absorption of sulfur dioxide,but the stage is signed by sulfur dioxide detected in the exit gas flows.In addition,the gas film mass transfer controlling ste Pis observed for the absorption of sulfur dioxide in stage I and stage II.The temperature of sodium sulfide aqueous solution negatively influences the overall rate of absorption of sulfur dioxide and the concerntration of sodium sulfide aqueous solution does not influence the overall rate.
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.
文摘Three novel cobalt(Ⅱ) complexes of the benzoaza-15-crown-5 Schiff base were synthesized and characterized.For comparison,the catalytic activity of the complexes were also investigated.The mechanism of the phenol catalytic oxidation were studied.The acid effect of reaction system,structural effect of the complexes,and effect of temperature on the rate of the phenol catalytic oxidation by the mimetic peroxidase were discussed.The results show:the schiff base cobalt(Ⅱ) complexes as peroxidase mimics exhibit good catalytic activity and similar catalytic character to natural enzyme.
文摘The title complexes Ni(HDPC)2·3H2O and Cu(DPC)(H2DPC)·2H2O have been synthesized in aqueous solution by the reaction of pyridine-2,6-dicarboxylic(H2DPC) with NiCl2·6H2O and CuCl2·3H2O,respectively.The enthalpy change of formation of the reaction on the title complexes in liquid-phase have been determined by a microcalorimeter,respectively. Thermodynamic parameters(the activation enthalpy,the activation entropy and the activation free energy),rate constant and kinetics parameters(the apparent activation energy,the pre-exponential constant and the reaction order) of the title reaction have been calculated.The formation of the two complexes were all exothermic reactions in the range of experimental temperature.The higher reaction velocity was obtained at higher temperature.
