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to moles of oleic acid. Comparisons of literature results are best
understood when these influencing factors are considered.
4. The IR spectra show the formation of -ONO2, -O2NO2,
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exposed to nitrate radical. High molecular weight products are
also observed in the LC-MS measurements.
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result of increased hygroscopicity corroborates the reports by
Asad et al.18 and Broekhuizen et al.19 The increased hygroscopic
response of oxidized oleic acid particles suggests that aged
organic aerosol particles in the atmosphere may have a
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scattering and radiative forcing. Moreover, changes in hygro-
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in atmospheric aerosol particles can be estimated. Ozone
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Acknowledgment. We are grateful for support received from
the NSF Atmospheric Chemistry Program (ATM 0215357) and
the New York Community Trust Merck Fund. Valuable discus-
sion with Richard Schalek is appreciated.
References and Notes
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