A quantification of inorganic mass partitioning to particle between low/high humidity and with/without seed particle and VOCs.

다국어 초록 (Multilingual Abstract)

Ammonia (NH3) and nitrogen oxide (NOx) in the atmosphere have critical impacts on the nitrogen cycle, ecosystem, and secondary organic aerosol formation. NH3 and NOx uptake occurs into aerosol liquid water (ALW), which is formed in inorganic-rich hygroscopic particles at a high relative humidity (RH), and this is an important process in East Asia. Therefore, the NH3 participation in NOx photochemistry of secondary aerosol formation, focusing on quantifying inorganic compounds, needs to be explored.
In this study, we conduct photochemical reactions of particles in a smog chamber (6 m3) to monitor NH3 and NOx partitioning from the gas phase to wet aerosols, varying four different factors: relative humidity (RH), present of seed particle, present of volatile organic compound and effects of NOx concentration. Experiments are conducted separately to study the impact of those factor Atomizing solution of (NH4)2SO4 is introduced to the smog chamber as seed particles with polluted or clean relevant conditions while toluene is an organic precursor used for photochemistry. NH3 and NOx concentration is monitored online continuously for 3 hours while collected samples during the reaction time are weighted and then analyzed by Ion chromatography (IC) to determine cations (NH4+) and anions (SO42-, NO3-). As a result, a significant partitioning of semi-volatile inorganic from the gas phase to particles under high humidity with a present of seed particle. While organic did not show evidence of its effects on ammonium and nitrate formation, a lower concentration of gaseous caused a time delay on the formation of the inorganic compound in the particle phase.