化学放大法测量大气过氧自由基的技术进展

Advances in Chemical Amplification Measurement of Peroxy Radicals

大气过氧自由基(RO_2)是大气化学过程中的关键中间体自由基,在对流层光化学反应中占有重要地位,因此,对相关测量技术的研究具有极其重要的意义。化学放大法是RO_2测量中最常用的方法之一,是一种间接测量方法,通过在反应系统中加入过量的CO、NO气体,将低浓度、不易测量的过氧自由基通过链式反应转化为高浓度、易测量的NO_2进行测量,NO_2测量的准确性对化学放大法很重要。对化学放大法进行了总结,并着重分析了其中用于NO_2测量的方法,分析了现有方法的优点与不足,并对未来的发展作了展望。

Atmospheric peroxy radicals （RO2） are key intermediate radicals in the atmosphere, which occupy an important position in the tropospheric photochemical reaction processes. However, they are difficult to be measured because of their low concentration and high reactivity in the atmosphere. Chemical amplification, an indirect measurement technique, is one of the most commonly used methods of RO2 measurements. RO2 radicals are converted and ~mplified into high concentrations of stable NO2 via chain reactions by adding excess amount of CO and NO gas. Then the measurement of RO2 radicals could be achieved by measuringNO2 through different methods that are well developed. Chemical amplification is summarized, and differ- ent measurement methods of NO2 with their advantages and disadvantages are emphatically compared and analyzed. Finally, the directions for future research are prospected.