CAJ | 학술논문

利用自制的烟雾箱系统研究了臭氧与二乙胺和三乙胺的气相反应动力学.实验过程中保证二乙胺和三乙胺浓度远远大于臭氧浓度,使得实验在准一级条件下进行.加入环己烷以消除实验过程中可能产生的OH自由基对反应的影响.在(298±1)K和1.01×105 Pa条件下,测得臭氧与二乙胺和三乙胺反应的绝对速率常数值分别为(1.33±0.15)×10-17和(8.20±1.01)×10-17cm3·molecule-1·s-1.与文献中已有的其它胺类的臭氧反应数据比较后发现,臭氧与胺的反应可以用亲电反应机制来解释.另外,通过对比发现,臭氧与三取代的烷基胺类的反应速率要远远大于其与二取代的烷基胺类的反应速率.这在一定程度上可有助于解释外场观测到的气溶胶相中二烷基胺盐较多的事实.利用测得的速率常数和大气中臭氧浓度,还估算了二乙胺和三乙胺与臭氧反应的大气寿命.结果显示,与臭氧的反应是二乙胺和三乙胺在大气中的一种重要的消除途径,尤其是在污染严重地区.
이용자제적연무상계통연구료취양여이을알화삼을알적기상반응동역학.실험과정중보증이을알화삼을알농도원원대우취양농도,사득실험재준일급조건하진행.가입배기완이소제실험과정중가능산생적OH자유기대반응적영향.재(298±1)K화1.01×105 Pa조건하,측득취양여이을알화삼을알반응적절대속솔상수치분별위(1.33±0.15)×10-17화(8.20±1.01)×10-17cm3·molecule-1·s-1.여문헌중이유적기타알류적취양반응수거비교후발현,취양여알적반응가이용친전반응궤제래해석.령외,통과대비발현,취양여삼취대적완기알류적반응속솔요원원대우기여이취대적완기알류적반응속솔.저재일정정도상가유조우해석외장관측도적기용효상중이완기알염교다적사실.이용측득적속솔상수화대기중취양농도,환고산료이을알화삼을알여취양반응적대기수명.결과현시,여취양적반응시이을알화삼을알재대기중적일충중요적소제도경,우기시재오염엄중지구.
Kinetics of the reactions of ozone with diethylamine (DEA) and triethylamine (TEA) were investigated in a self-made Teflon chamber. Experiments were conducted under pseudo-first-order decay conditions using excess DEA and TEA. Cyclohexane was added to the reactor to quench OH radicals. At (298±1) K and 1.01×105 Pa, the measured absolute rate constants were (1.33±0.15)×10-17 cm3· molecule-1·s-1 for DEA and (8.20±1.01 )×10-17 cm3·molecule-1·s-1 for TEA. Comparing our results with data for the reactions of analogous amines with ozone, we propose that the amines react with ozone probably through an electrophilic reaction mechanism. In addition, the reactions of trialkylamines with ozone are all much faster than those of dialkylamines with ozone, which may explain the intriguing finding in several field studies where higher concentrations of dialkylammonium were detected in aerosol samples. The atmospheric lifetimes of DEA and TEA were also estimated based on the measured rate constants and the ambient tropospheric concentration of ozone, which indicates that the reaction with ozone is an important loss pathway for these amines in the atmosphere, especially in polluted areas.