Rapid production of highly oxidized molecules in isoprene aerosol via peroxy and alkoxy radical isomerization pathways in low and high NO_x environments: Combined laboratory, computational and field studies.

ABSTRACT: Recently, we identified seven novel hydroxy-carboxylic acids resulting from gas-phase reactions of isoprene in the presence of nitrogen oxides (NO_x), ozone (O₃), and/or hydroxyl radicals (OH). In the present study, we provide evidence that hydroxy-carboxylic acids, namely methyltartaric acids (MTA) are: (1) reliable isoprene tracers, (2) likely produced via rapid peroxy radical hydrogen atom (H) shift reactions (autoxidation mechanism) and analogous alkoxy radical H shifts in low and high NO_x environments respectively and (3) representative of aged ambient aerosol in the low NO_x regime. Firstly, MTA are reliable tracers of isoprene aerosol because they have been identified in numerous chamber experiments involving isoprene conducted under a wide

SUBMITTER: Jaoui M 

PROVIDER: S-EPMC8363757 | biostudies-literature | 2021 Jun

REPOSITORIES: biostudies-literature