Nighttime atmospheric oxidation for real organic films on atmospheric aerosol using real samples from the atmosphere

Oxidation of the organic films on atmospheric aerosol for climate change studies has previously concentrated on daytime oxidants (OH and O3). The behavior of real organic films extracted from the atmosphere at air-water interface of aerosol and cloud droplets with the night-time oxidant (NO3 radical) has not been studied. Our proposed experiment will characterise (film thickness) and study the reactivity of the film (kinetics) to atmospheric oxidation (NO3 radical) of surface-active films extracted from these samples. These precious samples are collected and need to be studied by a high flux Neutron reflectometer. If the oxidation kinetics demonstrate a film lifetime (with respect to oxidation by night-time NO3 radical) of less than 4 days the reaction must be included in atmospheric process modelling. The work supports a NERC grant between ISIS/RHUL and a new joint funded ISIS/RHUL PhD studentship.