When impervious surfaces are exposed to the atmosphere, surface films forms through the deposition, partioning and subsequent processing of atmospheric constituents. There is evidence suggesting that these films, referred to as grime, play a role in mediating organic contaminants in the atmosphere and more recently we have shown that they provide a photo-reactive environment for the formation NOx from HNO3 and possibly organic nitrogen species within the film.  These reactive processes are enhanced in the presence of water vapour.  We will present the results of quartz crystal microbalance measurements of the water uptake onto field-collected urban grime as well as an examination of film properties that may mediate this uptake. Using ATR spectroscopy, we probe the overall chemical and optic features of the grime samples; ion composition is measured using ion chromatography. We will report on how these evolve over multiple week sampling periods and different atmospheric and weather conditions.

Physical characterization of real urban grime

248th National Meeting (2014)

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.