In this paper,the hydrolysis of silicon nitride in pure water and 005mol·L-1 H2SO4 solution under the condition of ultrasonic irradiation was studied,and the influences of ultrasonic power and reactio...In this paper,the hydrolysis of silicon nitride in pure water and 005mol·L-1 H2SO4 solution under the condition of ultrasonic irradiation was studied,and the influences of ultrasonic power and reaction time on the hydrolysis of silicon nitride were investigated.In addition,we also compared the hydrolytic result of ultrasound with that of powerful agitation.The experimental results show that the hydrolytic ratio of silicon nitride is increasing with the rising of ultrasonic power and the lengthening of reaction time.The hydrolytic velocity in 005mol·L-1 H2SO4 solution is a little faster than that in pure water.And in lowpower ultrasound(100W～150W),the hydrolytic velocity is approximately equal to that in powerful agitation.However,the hydrolytic velocity is accelerated rapidly with the increasing of ultrasonic power.展开更多
Factors on degradation of chlorothalonil(CLT) in water by high frequency ultrasonic irradiation were investigated.The effects of initial concentration of chlorothalonil,dosages of tertiary butyl alcohol,humic acid and...Factors on degradation of chlorothalonil(CLT) in water by high frequency ultrasonic irradiation were investigated.The effects of initial concentration of chlorothalonil,dosages of tertiary butyl alcohol,humic acid and initial pH value on degradation of chlorothalonil,as well as the reaction mechanism were studied.The results reveal that chlorothalonil could be effectively degradated by ultrasonic irradiation.The reaction constant value kapp decreased from 0.014 1 to 0.010 2 min-1 with the initial concentration increasing from 50 to 400 μg/L during 180 min irradiation.Tertiary butyl alcohol had negative effect on chlorothalonil degradation,while lower concentration of humic acid promoted the sonolysis,and kapp declined with the further concentration increasing.The kapp varied little when the pH value ranged from 3.10 to 10.28.It may be concluded that mechanical and pyrolysis process played main roles on the degradation of chlorothalonil in ultrasonic irradiation rather than ·OH attack.The electrical energy per order(EEo) values for sonolysis degradation of CLT were also calculated to evaluate the cost of the process.展开更多
文摘In this paper,the hydrolysis of silicon nitride in pure water and 005mol·L-1 H2SO4 solution under the condition of ultrasonic irradiation was studied,and the influences of ultrasonic power and reaction time on the hydrolysis of silicon nitride were investigated.In addition,we also compared the hydrolytic result of ultrasound with that of powerful agitation.The experimental results show that the hydrolytic ratio of silicon nitride is increasing with the rising of ultrasonic power and the lengthening of reaction time.The hydrolytic velocity in 005mol·L-1 H2SO4 solution is a little faster than that in pure water.And in lowpower ultrasound(100W～150W),the hydrolytic velocity is approximately equal to that in powerful agitation.However,the hydrolytic velocity is accelerated rapidly with the increasing of ultrasonic power.
基金Project(2008ZX07421-002) supported by the National Major Project of Science & Technology Ministry of ChinaProject(2008AA06A412) supported by the National High Technology Research and Development Program of ChinaProject(20009-K7-4) supported by the Research and Development of Ministry of Housing and Urban-Rural Development of China
文摘Factors on degradation of chlorothalonil(CLT) in water by high frequency ultrasonic irradiation were investigated.The effects of initial concentration of chlorothalonil,dosages of tertiary butyl alcohol,humic acid and initial pH value on degradation of chlorothalonil,as well as the reaction mechanism were studied.The results reveal that chlorothalonil could be effectively degradated by ultrasonic irradiation.The reaction constant value kapp decreased from 0.014 1 to 0.010 2 min-1 with the initial concentration increasing from 50 to 400 μg/L during 180 min irradiation.Tertiary butyl alcohol had negative effect on chlorothalonil degradation,while lower concentration of humic acid promoted the sonolysis,and kapp declined with the further concentration increasing.The kapp varied little when the pH value ranged from 3.10 to 10.28.It may be concluded that mechanical and pyrolysis process played main roles on the degradation of chlorothalonil in ultrasonic irradiation rather than ·OH attack.The electrical energy per order(EEo) values for sonolysis degradation of CLT were also calculated to evaluate the cost of the process.
