Abstract：
Mixing states of aerosol particles are crucial for understanding the role of aerosols in influencing air quality and climate. However, a fundamental understanding of the complex mixing states is still lacking because most traditional analysis techniques only reveal bulk chemical and physical properties with limited surface and 3-D information. In this research, 3-D molecular imaging enabled by ToF-SIMS was used to elucidate the mixing states of PM2.5 samples obtained from a typical Beijing winter haze event. In light pollution cases, a thin organic layer covers separated inorganic particles; while in serious pollution cases, ion exchange and an organic-inorganic mixing surface on large-area particles were observed. The new results provide key 3-D molecular information of mixing states, which is highly potential for reducing uncertainty and bias in representing aerosol-cloud interactions in current Earth System Models and improving the understanding of aerosols on air quality and human health.
摘要：
气溶胶颗粒的混合状态对于理解气溶胶在影响空气质量和气候方面的作用至关重要。然而,对复杂混合状态的基本理解仍然缺乏，因为大多数传统的分析技术仅揭示具有有限表面和3-D信息的整体化学和物理性质。在这项研究中,通过ToF-SIMS实现的3-D分子成像用于阐明从典型的北京冬季霾事件中获得的PM2.5样品的混合状态。在光污染的情况下，一层薄的有机层覆盖分离的无机颗粒；而在严重污染的情况下，在大面积颗粒上观察到离子交换和有机-无机混合表面。新结果提供了混合态的关键3-D分子信息，这对于减少当前地球系统模型中气溶胶-云相互作用的不确定性和偏见以及提高对气溶胶对空气质量和人类健康的理解具有很大的潜力。
