Yangxi Chu

Abstract Click to copy section linkSection link copied! The ammonia-amine exchange reaction serves as a key driver of atmospheric aerosol aging, yet its modulation by secondary organic aerosols (SOA), particularly those containing organic acids, remains poorly understood. We investigated the uptake of dimethylamine (DMA) by internally mixed ammonium sulfate and glyoxylic acid (GA) particles under varying relative humidity (RH) and mixing ratios.

CO2 capture plants are a significant source of emission of monoethanolamine (MEA) in the atmosphere. As a potential MEA sink, the heterogeneous uptake of MEA by sulfuric acid (SA) particles can form particulate MEA sulfate (MEAS), changing the hygroscopicity of the particles. We determined the hygroscopicities of MEA salts, including MEAS, at different MEA:sulfate molar ratios over a wide range of relative humidity (RH) using an electrodynamic balance (EDB) and a water activity meter.

Atmospheric particles can be viscous. The limitation in diffusion impedes the mass transfer of oxidants from the gas phase to the particle phase and hinders multiphase oxidation processes. On the other hand, nitrate photolysis has been found to be effective in producing oxidants such as OH radicals within the particles. Whether nitrate photolysis can effectively proceed in viscous particles and how it may affect the physicochemical properties of the particle have not been much explored.