Showing papers by "Janet Arey published in 2010"
TL;DR: For toluene, o-, m-, and p-xylene, and 1,3,5-trimethylbenzene, the yields showed a dependence on NO2, decreasing with increasing NO2 concentration and with no evidence for formation of glyoxal or methylglyoxal from the reactions of the OH-aromatic adducts with NO2.
Abstract: Aromatic hydrocarbons comprise ∼20% of non-methane volatile organic compounds in urban areas and are transformed mainly by atmospheric chemical reactions with OH radicals during daytime. In this work we have measured the formation yields of glyoxal and methylglyoxal from the OH radical-initiated reactions of toluene, xylenes, and trimethylbenzenes over the NO2 concentration range (0.2−10.3) × 1013 molecules cm−3. For toluene, o-, m-, and p-xylene, and 1,3,5-trimethylbenzene, the yields showed a dependence on NO2, decreasing with increasing NO2 concentration and with no evidence for formation of glyoxal or methylglyoxal from the reactions of the OH-aromatic adducts with NO2. In contrast, for 1,2,3- and 1,2,4-trimethylbenzene the glyoxal and methylglyoxal formation yields were independent of the NO2 concentration within the experimental uncertainties. Extrapolations of our results to NO2 concentrations representative of the ambient atmosphere results in the following glyoxal and methylglyoxal yields, respec...
74 citations
TL;DR: The isomer distributions and yields of the nitroarenes formed from the gas-phase reactions of naphthalene and alkylnaphthalenes with NO3 radicals are reported, and the ratios of 2-methyl-4-nitronaphthalENE/1- methyl-5-nitronicle and 2-7DM4NN/1,7DM5NN are proposed to be sensitive markers of nitroAREne formation from NO3 versus OH radical chemistry.
Abstract: Nitrated polycyclic aromatic hydrocarbons (nitro-PAHs) are potential human carcinogens and it has been postulated that their abundance profiles in ambient air in polluted urban areas are influenced...
20 citations
TL;DR: Noda et al. as discussed by the authors investigated the formation of cresols from the reactions of OH radicals with m-xylene and p-cymene, and obtained upper limits of < 1% for formation of each cresol isomer from OH + m-oxylene and < 2% for the formation from OH+p-cymmene.
17 citations
TL;DR: The 4-hydroxyhexanal yield increased with increasing NO concentration, and the hydroxynitrate formed from reaction of the hydroxyalkylperoxy radicals with NO is attributed to a minor pathway of the RC(*)HOH + O(2) reaction in the presence of NO.
Abstract: Products of the gas-phase reactions of OH radicals with 1-octene and 7-tetradecene have been investigated at 296 +/- 2 K and atmospheric pressure of air, using gas chromatography, direct air sampling atmospheric pressure ionization tandem mass spectrometry, and in situ Fourier transform infrared spectroscopy We observe the hydroxynitrate(s) formed from reaction of the hydroxyalkylperoxy radicals with NO; heptanal and 4-hydroxyhexanal from decomposition of the 1,2-hydroxyoctoxy and 7-hydroxy-8-tetradecoxy radicals; and dihydroxynitrates and dihydroxycarbonyls formed after isomerization of the intermediate 1,2-hydroxyalkoxy radicals Formic acid formation was also observed from the 1-octene reaction, in approximately 3% yield In the presence of approximately 15 x 10(14) molecules cm(-3) of NO, the respective molar formation yields of heptanal and 4-hydroxyhexanal were 28 +/- 3% and 4% from 1-octene, and 86 +/- 11% and 6% from 7-tetradecene The 4-hydroxyhexanal yield increased with increasing NO concentration, and we attribute 4-hydroxyhexanal + HC(O)OH formation to a minor pathway of the RC(*)HOH + O(2) reaction in the presence of NO The reaction pathways occurring are discussed
16 citations
TL;DR: Using a relative rate method, rate constants have been measured for the reactions of OH radicals with 4,4-dimethyl-1-pentene and its major reaction product, 3,3-dimethybutanal and are expected to be very close to the fraction of the overall reaction proceeding by H-atom abstraction.
Abstract: Using a relative rate method, rate constants have been measured for the reactions of OH radicals with 4,4-dimethyl-1-pentene [(CH3)3CCH2CH═CH2] and its major reaction product, 3,3-dimethylbutanal [...
7 citations
TL;DR: Glycolaldehyde, malonaldehyde, and 1,4-butanedial are expected products of the reaction of OH radicals with 4-hydroxybutanal, and glycolaldehyde and mal onaldehyde are expected Products of the Reaction of OH radical with 3-hydropropanal.
Abstract: Rate constants for the gas-phase reactions of the OH radical with 1,4-butanediol,4-hydroxybutanal, and 3-hydroxypropanalwere measured at 298 +/- 2 K and atmospheric pressure using a relative rate technique and with 4-hydroxybutanal and 3-hydroxypropanal being formed in situ from the OH + 1,4-butanediol reaction, and were (in units of 10(-11) cm(3) molecule(-1) s(-1)) 3.67 +/- 0.31, 3.0(-1.0)(+1.5), and 3.5(-1.0)(+1.3), respectively, with the latter being a lower limit because of the possibility of second-generation formation of 3-hydroxypropanal from OH + 4-hydroxybutanal. The measured formation yields of 4-hydroxybutanal and 3-hydroxypropanal from the OH + 1,4-butanediol reaction in the presence of NO were 58 +/- 19% and 55 +/- 12%, respectively. In addition to the formation of 4-hydroxybutanal and 3-hydroxypropanal, gas chromatography-mass spectrometric analyses of reacted OH + 1,4-butanediol reactionsshowedformation of glycolaldehyde [HOCH(2)CHO], malonaldehyde [HC(O)CH2CHO], and 1,4-butanedial [HC(O)CH(2)CH(2)CHO]. Glycolaldehyde, malonaldehyde, and 1,4-butanedial are expected products of the reaction of OH radicals with 4-hydroxybutanal, and glycolaldehyde and malonaldehyde are expected products of the reaction of OH radicals with 3-hydroxypropanal. Reaction mechanisms are presented and discussed.
5 citations
Journal Article•
3 citations