Phys.org October 13, 2021
Unsaturated fatty acids contribute to urban cooking emissions and sea spray aerosols. The phase state of organic aerosols is a significant factor in determining aerosol reactivity, water uptake and atmospheric lifetime with wide implications for cloud formation, climate, air quality and human health. Researchers in the UK studied physical and chemical changes in crystalline acid–soap complex in acoustically levitated oleic acid–sodium oleate particles during exposure to humidity and the atmospheric oxidant ozone. It revealed a phase gradient consisting of a disordered liquid crystalline shell and crystalline core. Ozonolysis is significantly slower in the crystalline phase compared with the liquid phase, and a significant portion of unreacted material remains after extensive oxidation. According to the researchers atmospheric lifetimes of surface-active organic species in aerosols are highly phase-dependent, potentially impacting climate, urban air quality and long-range transport of pollutants such as polycyclic aromatic hydrocarbons…read more. Open Access TECHNICAL ARTICLE
