Laboratory Chamber Studies on Gas-Phase Photooxidation and Aqueous Chemistry of Phenols and Methoxyphenols in Biomass Burning Organic Aerosol Formation

在乔治亚理工学院化学系环境化学科学项目的支持下，佐治亚理工学院的Nga Lee Ng和Rodney Weber及其学生将研究大气中生物质燃烧排放的有机气溶胶(悬浮在空气中的微小颗粒)的形成。了解这些颗粒物是如何形成的，对于评估它们对气候和人类健康的影响很重要。在火灾期间，植物中的木质组织在高温下分解释放出大量的挥发性有机化合物(VOCs)，包括酚类化合物。该团队将研究这些酚类化合物在与大气相关的条件下如何反应形成有机颗粒，以及这些颗粒吸收光线的能力。该团队还将开发和实施一个关于燃烧生物质烟雾中的颗粒物的教学模块，让大亚特兰大地区的中学生接触到与野火和空气污染有关的新科学概念。苯酚和甲氧基酚是生物质燃烧排放的非甲烷有机化合物的重要组成部分。在现实的环境条件下，这些重要的生物质燃烧排放物的氧化和进一步的化学处理还没有得到系统的研究。通过综合实验室实验，本项目将研究一组酚类化合物在不同反应条件下的气相氧化生成二次有机气溶胶(SOA)及其后续的水相处理。还将对气溶胶的光学性质进行表征。这项研究的结果将为确定释放到环境中的酚类化合物的气相和水相化学参数提供基本数据，并提供有关它们形成的气溶胶的更多信息。这些数据反过来将有助于科学家开发用于解释这种有机气溶胶的大气模型。这一奖项反映了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。

With support from the Environmental Chemical Sciences Program in the Division of Chemistry Nga Lee Ng and Rodney Weber at Georgia Tech and their students will study the formation of organic aerosols (tiny particles suspended in the air) from biomass burning emissions in the atmosphere. Understanding how these particles form is important for evaluating their impact on climate and human health. During fires, the decomposition of woody tissues in plants at high temperatures releases a significant level of volatile organic compounds (VOCs), including phenolic compounds. The team will investigate how these phenolic compounds react under atmospherically relevant conditions to form organic particles, as well as the ability of these particles to absorb light. The team will also develop and implement an instruction module on particles from biomass-burning smoke to expose middle school students in the greater Atlanta area to new scientific concepts related to wildfires and air pollution. Phenols and methoxyphenols are a significant part of non-methane organic compounds emitted from biomass burning. The oxidation and further chemical processing of these important biomass burning emissions has not been systematically studied under realistic ambient conditions. Through comprehensive laboratory chamber experiments, this project will investigate secondary organic aerosol (SOA) formation from gas-phase oxidation of a set of phenolic compounds under different reaction conditions and their subsequent aqueous-phase processing. The optical properties of aerosols will also be characterized. Results from this study will provide fundamental data to parameterize the gas-phase and aqueous-phase chemistries of phenolic compounds released into the environment and provide enhanced information on the aerosols that they form. These data will, in turn, be useful to scientist developing atmospheric models designed to account for such organic aerosols.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.