Evidence for high molecular weight nitrogen-containing organic salts in urban aerosols.
Published
Journal Article
High molecular weight (M(w)) species were observed at substantial intensities in the positive-ion mass spectra in urban Shanghai aerosols collected from a single-particle time-of-flight mass spectrometer (in the m/z range 250-500) during three separate periods over 2007-2009. These species correlate well with the CN(-) mass signal, suggesting that C-N bonds are prevalent and that the observed high-M(w) species are potentially nitrogen-containing organic salts. Anti-correlation with the ambient O(3) concentration suggests that photochemical oxidants are not involved directly in the formation of these species. The Mannich reaction, among amines (or ammonia), formaldehyde, and carbonyls with an adjacent, acidic proton, is proposed as a plausible pathway leading to these organic salts. Although the high-M(w) species observed in the single-particle mass spectra appear to be nitrogen-containing organics, further chemical confirmation is desired to verify if the proposed Mannich reaction can explain the formation of these high-M(w) species in regions where ammonia, amines, and carbonyls are prevalent.
Full Text
Duke Authors
Cited Authors
- Wang, X; Gao, S; Yang, X; Chen, H; Chen, J; Zhuang, G; Surratt, JD; Chan, MN; Seinfeld, JH
Published Date
- June 2010
Published In
Volume / Issue
- 44 / 12
Start / End Page
- 4441 - 4446
PubMed ID
- 20476743
Pubmed Central ID
- 20476743
Electronic International Standard Serial Number (EISSN)
- 1520-5851
International Standard Serial Number (ISSN)
- 0013-936X
Digital Object Identifier (DOI)
- 10.1021/es1001117
Language
- eng