Atmospheric aerosol, particulate matter suspended in the air we breathe, exerts a strong impact on our health and the environment. Controlling the amount of particulate matter in air is difficult, as there are many ways particles can form by both natural and anthropogenic processes. We gain insight into the sources of particulate matter through chemical composition measurements. A substantial portion of atmospheric aerosol is organic, and this organic matter is exceedingly complex on a molecular scale, encompassing hundreds to thousands of individual compounds that distribute between the gas and particle phases. Because of this complexity, no single analytical technique is sufficient. However, mass spectrometry plays a crucial role owing to its combination of high sensitivity and molecular specificity. This review surveys the various ways mass spectrometry is used to characterize atmospheric organic aerosol at a molecular level, tracing these methods from inception to current practice, with emphasis on current and emerging areas of research. Both offline and online approaches are covered, and molecular measurements with them are discussed in the context of identifying sources and elucidating the underlying chemical mechanisms of particle formation. There is an ongoing need to improve existing techniques and develop new ones if we are to further advance our knowledge of how to mitigate the unwanted health and environmental impacts of particles.

中文翻译：

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质谱分析大气有机气溶胶的分子特性。

大气中的气溶胶是悬浮在我们呼吸的空气中的颗粒物，对我们的健康和环境产生了重大影响。控制空气中颗粒物的数量非常困难，因为自然和人为过程均可通过多种方式形成颗粒。通过化学成分测量，我们可以深入了解颗粒物的来源。大气气溶胶的很大一部分是有机物，这种有机物在分子规模上极其复杂，涵盖了成百上千个分布在气相和颗粒相之间的单个化合物。由于这种复杂性，没有任何一种分析技术是足够的。但是，质谱由于其高灵敏度和分子特异性的结合而起着至关重要的作用。这篇综述调查了使用质谱法在分子水平上表征大气有机气溶胶的各种方法，并追踪了从开始到当前实践的这些方法，重点是当前和新兴的研究领域。涵盖了离线方法和在线方法，并在识别来源和阐明颗粒形成的潜在化学机理的背景下讨论了使用它们的分子测量。如果我们要进一步提高我们如何减轻颗粒的有害健康和环境影响的知识，则需要不断改进现有技术并开发新技术。涵盖了离线方法和在线方法，并在识别来源和阐明颗粒形成的潜在化学机理的背景下讨论了使用它们的分子测量。如果我们要进一步提高我们如何减轻颗粒的有害健康和环境影响的知识，则需要不断改进现有技术并开发新技术。涵盖了离线方法和在线方法，并在识别来源和阐明颗粒形成的潜在化学机理的背景下讨论了使用它们的分子测量。如果我们要进一步提高我们如何减轻颗粒的有害健康和环境影响的知识，则需要不断改进现有技术并开发新技术。