Collaborative Research: Impact of Aerosol Viscosity, Phase Separation, and Internal Structure on Isoprene-Derived SOA (Secondary Organic Aerosol) Formation

该项目致力于将描述大气中小有机颗粒的形成速度、浓度和空间分布的测量结果与模型之间的差距降至最低。将在北卡罗来纳大学的环境室设施中进行实验室研究，以测量气溶胶和气相产品的关键物理化学性质。这些结果将被用于改进二次有机气溶胶(SOA)的形成模型，以更好地为有关空气质量、人类健康和气候的决策提供信息。二次有机气溶胶将检验较高粘度和相分离将抑制异戊二烯环氧二醇(IEPOX)反应性吸收的假设。检验这一假设的实验计划的四个目标包括：(1)确定IEPOX的反应性吸收作为颗粒粘度的函数；(2)确定IEPOX在具有复杂形态的颗粒上的反应性吸收；(3)鉴定不同粘度和形态的IEPOX衍生的SOA组分的分子组成和物理化学性质；以及(4)表征IEPOX的反应性吸收化学反应产生的挥发性产品。

The project strives to minimize the gap between measurements and models that characterize the formation rates, concentrations, and spatial distributions of small organic particles in the atmosphere. Laboratory studies will be conducted in the UNC Environmental Chamber Facility to measure key physicochemical properties of aerosol and gas phase products. The results will be applied to improve models of secondary organic aerosol (SOA) formation to better inform policy decisions about air quality, human health, and climate.The PIs will test the hypothesis that higher viscosity and phase-separation will suppress the reactive uptake of isoprene epoxydiols (IEPOX). The four objectives of the experimental plan to test this hypothesis include the (1) determination of the reactive uptake of IEPOX as a function of particle viscosity; (2) determination of the reactive uptake of IEPOX on particles with complex morphologies; (3) identification of the molecular composition and physicochemical properties of the IEPOX-derived SOA constituents for different viscosities and morphologies; and (4) characterization of volatile products resulting from reactive uptake chemistry of IEPOX.