CAREER: Multi-Generational Aging of Atmospheric Organic Mixtures

这个职业项目的重点是大气有机气溶胶混合物中发生的长期化学变化。大气中的有机分子可能会对气候、空气质量以及人类健康和环境产生重大影响。这项研究的目标之一是开发一种更准确的方法来估计随着气溶胶老化而排放到大气中的碳的比例，这些碳排放到大气中的冷凝相包括气溶胶和表面膜。了解较慢的老化反应的类型和程度是了解和预测碳混合物在大气气溶胶中行为的关键。本研究的中心假设是，当有机混合物老化时，官能团分布发生变化，从而使随后的吸积反应成为可能。这一假设是基于这位研究人员之前的工作，他发现a-蒎烯和食品烹饪有机气溶胶薄膜都显示出低聚的证据，而且陈化时间很长(几天到几周)。这项研究的目的是：(1)调查水蒸气对次生有机气溶胶多代老化的影响，(2)调查城市污垢成分，包括食物烹饪有机气溶胶和环境表面膜的老化过程，以及(3)通过与当地高中合作发展与空气污染相关的学习经验，帮助吸引和留住大气科学专业的学生。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

This CAREER project focuses on long-term chemical changes that take place in mixtures of atmospheric organic aerosol. Organic molecules in the atmosphere can have large impacts on climate, air quality, and on human health and the environment. One of the goals of this research is to develop a more accurate way to estimate the fraction of carbon emitted into the atmosphere that stays in the condensed phase, both in aerosol and in surface films, as the aerosol ages. Knowledge about the types and extents of slower aging reactions is key to understanding and predicting the behaviors of carbon mixtures in the atmospheric aerosols.The central hypothesis of this research is that when organic mixtures are aged, functional group distributions change, enabling subsequent accretion reactions. The hypothesis is based on prior work by this investigator who has found that both a-pinene and food cooking organic aerosol films show evidence of oligomerization with long aging times (days to weeks). The objectives of this research are to: (1) investigate the impact of water vapor on the multi-generational aging of secondary organic aerosol, (2) investigate the aging process for components of urban grime, including food cooking organic aerosol and ambient surface films, and (3) help attract and retain students in the atmospheric sciences by partnering with local high schools to develop learning experiences related to air pollution.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.