AGS-PRF: Atmospheric Lifecycle of Organic Carbon Through Multiple Generations of Aging

这是一个博士后研究奖学金，目的是描述大气中气态和颗粒态碳的化学性质。实验室实验将在环境舱中进行，以观察二次有机气溶胶的形成和有机化合物在几天内的老化。这些结果将有助于更好地理解大气碳循环，这对于制定减轻有机碳对空气质量和气候影响的政策至关重要。实验将在麻省理工学院的一个反应室中进行，使用全气相有机物(TGO)仪器、Aerodyne气溶胶质谱仪(AMS)、化学电离质谱仪(CIMS)和其他仪器来提供特定类别化合物及其氧化产物的详细组成数据。通过利用稳定亚硝酸的光解生成羟基自由基使前体在大气中氧化，将在反应室中模拟长达三天的大气老化。将开发几种简化的参数化学表示法来描述有机气溶胶的化学性质和化学转化，并模拟其在大气中的氧化途径。这些实验将有助于限制大气中总碳的收支。

This is a Postdoctoral Research Fellowship with the objective of characterizing the chemical properties of gas- and particle-phase carbon in the atmosphere. Laboratory experiments will be conducted in an environmental chamber to observe the formation of secondary organic aerosol and the aging of organic compounds over several days. The results will lead to a better understanding of the atmospheric carbon cycle essential for developing policies that mitigate the effects of organic carbon on air quality and climate.The experiments will take place in a reaction chamber at MIT using a Total Gas-phase Organics (TGO) instrument, an Aerodyne Aerosol Mass Spectrometer (AMS), a Chemical Ionization Mass Spectrometer (CIMS), and other instrumentation to provide detailed compositional data about specific classes of compounds and their oxidation products. Up to three days of atmospheric aging will be simulated in the reaction chamber through the atmospheric oxidation of precursors using the photolytic formation of hydroxyl radical from a steady stream of nitrous acid. Several reduced parameter chemical representations will be developed to describe the chemical properties and chemical transformations of organic aerosol and to model its oxidation pathways in the atmosphere. The experiments will help to constrain the budget of total carbon in the atmosphere.