摘要：Aerosol mixing state is one of the most important factors determining the impacts of aerosol particles on aerosol-cloud-climate interactions and human health. The size, composition, and morphology of about 32,000 single particles are analyzed using transmission electron microscopy (TEM) to evaluate per-particle mixing state. Based on the TEM analysis, we quantify aerosol mixing state and examine the impacts of per-particle mixing state on cloud condensation nuclei (CCN) properties and particle deposition efficiency along the human respiratory tract. Assuming homogeneous chemical composition across the aerosol population, a common practice in many global and regional models to various extents, we show that such simplification of mixing state representation could potentially lead to remarkable errors, a maximum of about 90% and 35%, in CCN concentrations and deposition efficiency calculations respectively. Our results from ambient per-particle observations highlight the importance of considering aerosol mixing state in both air quality models and climate models.
