SGER: Smog Chamber Investigations into Reactions of Tertiary Amines with NOy

PI和他的同事将在加州大学河滨分校进行一系列烟雾室内实验，以研究小胺与活性氮(NOY)化合物的反应动力学和产物。尽管越来越多的证据表明烷基胺可能是颗粒成分的前体，但对其可能的化学机制进行的实验室研究很少，也没有研究胺与硝酸根(NO3)和五氧化二氮(N2O5)的相互作用。将通过模拟大气中的烷基胺反应的受控实验室研究来研究颗粒形成速度和机理。这些研究将集中于胺与硝酸根和五氧化二氮的反应，以及它们的凝聚相(颗粒)产物。气相胺浓度将使用质子转移反应质谱仪(PTRMS)进行监测，而气溶胶成分将使用高分辨率飞行时间气溶胶质谱仪(TOF-AMS)进行表征。气溶胶的粒度分布也将通过扫描流动颗粒测定仪(SMPS)获得，重量样品将使用质谱仪技术进行离线化学分析。对胺的气溶胶形成反应的研究将提供有关全球氮循环的信息。目前，全球有机氮模型中没有考虑颗粒态胺。这项工作将更加清晰地阐明大气中还原有机氮的去向，有助于了解农业大气污染物的去向。其他更广泛的影响包括支持一名博士生进行雾霾室内研究，这将成为他/她论文的一部分，以及支持本科生研究助理对颗粒物进行数据分析和离线化学分析。

The PI and coworkers will conduct a series of smog chamber experiments at the University of California, Riverside to study the reaction kinetics and products of small amines with reactive nitrogen (NOy) compounds. Despite mounting evidence that alkyl amines may be precursors to particle constituents, few laboratory studies of the possible chemical mechanisms have been conducted, and none have looked at the interactions of amines with the nitrate radical (NO3) and dinitrogen pentoxide (N2O5). Particle formation rates and mechanisms will be investigated with controlled laboratory studies simulating alkyl amine reactions in the atmosphere. The studies will focus on amine reactions with nitrate radical and dinitrogen pentoxide, and their condensed-phase (particulate) products. Gas-phase amine concentrations will be monitored using a proton transfer reaction mass spectrometer (PTRMS) while aerosol composition will be characterized with a high resolution time-of-flight aerosol mass spectrometer (TOF-AMS). Aerosol size distributions will also be obtained from a scanning mobility particle sizer (SMPS), and gravimetric samples will be chemically analyzed off-line using mass spectrometry techniques. Studies of aerosol formation reactions from amines will yield information on the global cycle of nitrogen. Currently, particulate phase amines are not accounted for in global models of organic nitrogen. This work should more clearly elucidate the fate of reduced organic nitrogen in the atmosphere, and will be helpful for understanding the fate of agricultural air pollutants. Other broader impacts include support for one Ph.D. student to perform the smog chamber studies, which will become part of his/her dissertation, and support for undergraduate research assistants to perform data analysis and off-line chemical analysis of particles.