Measurements of alkyl and multifunctional organic nitrates at a rural site in Ontario

Abstract

Abstract. Measurements of alkyl and multifunctional organic nitrates were conducted at a rural site in Ontario during periods with varying levels of photochemical activity. On August 6 and August 21-23, 1992, a total of 17 organic nitrates (12 C3-C6 alkyl nitrates, 4 C2-C4 hydroxynitrates and 1,2-dinitrooxybutane) were quantitatively determined in atmospheric samples. The sum of the organic nitrate concentrations was found to be correlated with ozone and ranged from 12 to 140 parts per trillion (volume). The total concentration of organic nitrates measured contributed from 0.5 to 3.0% to the total odd nitrogen species. On average, the alkyl nitrates represented 82%, the hydroxynitrates 16%, and the dinitrate 2% of the total measured organic nitrates. Unidentified organic nitrate peaks determined from an organic nitrate selective detector were found to contribme an additional 0.25% to the total odd nitrogen budget. The distribution of alkyl and hydroxy nitrates measured was found to be reasonably consistent with computed relative production rates, for photochemically active air masses. Although the inclusion of the multifunctional organic nitrates does not significantly change the measured contribution of these species to NO.,, it is shown that the isoprene nitrates may ß , x y contribute as much as the combined contribution of all the measured organic nitrates.

Levels and pattern of volatile organic nitrates and halocarbons in the air at Neumayer Station (70°S), Antarctic

“…The reaction of alkenes with either Å OH during daytime or with NO Å 3 during nighttime in the presence of NO x leads to the formation of multifunctional organic nitrates like hydroxy alkyl nitrates or alkyl dinitrates (O'Brien et al, 1995;O'Brien et al, 1997;Kastler and Ballschmiter, 1998;Kastler and Ballschmiter, 1999). Moreover, organic nitrates formed by the reaction of isoprene have recently been reported (Werner et al, 1999).…”

“…O'Brien reported 1995 for the first time the occurrence of four alkyl hydroxy nitrates and one alkyl dinitrate (O'Brien et al, 1995;O'Brien et al, 1997). Recently additional hydroxy alkyl nitrates and 30 alkyl dinitrates were identified in urban air (Kastler and Ballschmiter, 1998;Kastler and Ballschmiter, 1999;Fischer et al, 2000).…”

Increased Thermostability of Thylakoid Membranes in Isoprene-Emitting Leaves Probed with Three Biophysical Techniques

“…Owing to the high reactivity and fast oxidation by hydroxyl radicals in the atmosphere, isoprene can increase the formation of atmospheric ozone (Monson and Holland, 2001;Kleindienst et al, 2007), organic nitrates (O'Brien et al, 1995), and peroxyacylnitrates (Sun and Huang, 1995). Isoprene is also a significant factor in secondary aerosol formation, with direct and indirect effects on the global radiation balance of the atmosphere (Claeys et al, 2004;Matsunaga et al, 2005;Kroll et al, 2006;Ervens et al, 2008;Paulot et al, 2009).…”

Preparing to Measure the Effects of the NOxSIP Call— Methods for Ambient Air Monitoring of NO, NO2, NOy, and Individual NOzSpecies

“…65 Hao et al 66 describe the use of post-column thermal decomposition for a variety of nitrates to NO 2 followed by luminol chemiluminescence-based detection. O'Brien et al 67 describe measurements of 17 alkyl nitrates and multifunctional organic nitrates by GC followed by an in-series combination of ECD and pyrolysis/luminol chemiluminescence detection.…”