Center for Atmospheric Particle Studies, Carnegie Mellon University, Pittsburgh, PA 15217, USA.
Proc Natl Acad Sci U S A. 2012 Aug 21;109(34):13503-8. doi: 10.1073/pnas.1115186109. Epub 2012 Aug 6.
The Multiple Chamber Aerosol Chemical Aging Study (MUCHACHAS) tested the hypothesis that hydroxyl radical (OH) aging significantly increases the concentration of first-generation biogenic secondary organic aerosol (SOA). OH is the dominant atmospheric oxidant, and MUCHACHAS employed environmental chambers of very different designs, using multiple OH sources to explore a range of chemical conditions and potential sources of systematic error. We isolated the effect of OH aging, confirming our hypothesis while observing corresponding changes in SOA properties. The mass increases are consistent with an existing gap between global SOA sources and those predicted in models, and can be described by a mechanism suitable for implementation in those models.
多腔气溶胶化学老化研究（MUCHACHAS）检验了这样一个假设，即羟基自由基（OH）老化会显著增加第一代生物成因二次有机气溶胶（SOA）的浓度。OH 是大气中的主要氧化剂，MUCHACHAS 采用了非常不同设计的环境室，使用多种 OH 源来探索一系列化学条件和潜在的系统误差来源。我们隔离了 OH 老化的影响，证实了我们的假设，同时观察到 SOA 性质的相应变化。质量的增加与全球 SOA 源与模型预测之间存在的差距一致，并且可以用一种适合于在这些模型中实施的机制来描述。
