12C/13C kinetic isotope effects of the gas-phase reactions of isoprene, methacrolein, and methyl vinyl ketone with OH radicals
| dc.contributor.author | Iannone, Richard | |
| dc.contributor.author | Koppmann, Ralf | |
| dc.contributor.author | Rudolph, Jochen | |
| dc.date.accessioned | 2010-01-22T16:19:41Z | |
| dc.date.available | 2010-01-22T16:19:41Z | |
| dc.date.issued | 09-Mar | |
| dc.description.abstract | The stable-carbon kinetic isotope effects (KIEs) for the gas-phase reactions of isoprene, methacrolein (MACR), and methyl vinyl ketone (MVK) with OH radicals were studied in a 25 L reaction chamber at (298 ± 2) K and ambient pressure. The time dependence of both the stable-carbon isotope ratios and the concentrations was determined using a gas chromatography combustion isotope ratio mass spectrometry (GCC-IRMS) system. The volatile organic compounds (VOCs) used in the KIE experiments had natural-abundance isotopic composition thus KIE data obtained from these experiments can be directly applied to atmospheric studies of isoprene chemistry. All 13C/12C KIE values are reported as ε values, where ε = (KIE – 1) × 1000‰, and KIE = k12/k13. The following average stable-carbon KIEs were obtained: (6.56±0.12)‰ (isoprene), (6.47±0.27)‰ (MACR), and (7.58±0.47)‰ (MVK). The measured KIEs all agree within uncertainty to an inverse molecular mass (MM) dependence of OHε(‰) = (487±18)MM–1,which was derived from two previous studies [J. Geophys. Res. 2000, 105, 29329–29346; J. Phys. Chem. A 2004, 108, 11537–11544]. Upon adding the isoprene, MACR, and MVK OHε values from this study, the inverse MM dependence changes only marginally to OHε(‰) = (485±14)MM–1. The addition of these isoprene OHε values to a recently measured set of O3ε values in an analogous study [Atmos. Environ. 2008, 42, 8728–8737] allows for estimates of the average change in the 12C/13C ratio due to processing in the troposphere. | en |
| dc.identifier.citation | Atmospheric Environment; 43, 3103-3110 | en |
| dc.identifier.uri | http://hdl.handle.net/10315/2916 | |
| dc.publisher | Elsevier | en |
| dc.rights.article | http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6VH3-4VTKKX4-4&_user=866177&_rdoc=1&_fmt=&_orig=search&_sort=d&_docanchor=&view=c&_searchStrId=1172730213&_rerunOrigin=google&_acct=C000045519&_version=1&_urlVersion=0&_userid=866177&md5=013255af887e744cbc14ef9d35e9ba4e | en |
| dc.rights.journal | http://www.elsevier.com/wps/find/journaldescription.cws_home/246/description#description | en |
| dc.rights.publisher | http://www.elsevier.com/wps/find/journal_browse.cws_home | en |
| dc.subject | GC-IRMS | en |
| dc.subject | Methyl Vinyl Ketone | en |
| dc.subject | Methacrolein | en |
| dc.subject | Isoprene | en |
| dc.subject | Kinetic isotope effect | en |
| dc.title | 12C/13C kinetic isotope effects of the gas-phase reactions of isoprene, methacrolein, and methyl vinyl ketone with OH radicals | en |
| dc.type | Article | en |