Table 8. Comparison of Gas-Phase Oxidation Product Yields From Sesquiterpenes, Isoprene, and Oxygenated Terpenes, on a Percent Mole (ppb/ppb) Basis, Observed in This Study With Results From Other Terpene Photooxidation Experiments Terpene Product Product Yield, % This Work Product Yield, % Other Studies Reference alpha-humulene m/z 219 3 +/- 0.5 9.5a [Jaoui and Kamens, 2003a] linalool acetone 25 51 [Shu et al., 1997] m/z 127 8.1 +/- 2 6.8b [Shu et al., 1997] m/z 129, 111, 93 75 +/- 10 46c [Shu et al., 1997] isoprene formaldehyde 160d 63 +/- 10 57 +/- 6 [Tuazon and Atkinson, 1990] [Miyoshi et al., 1994] MVK + MACR 60 - 87 +/- 11 61 55 +/- 6 54 54 [Paulson et al., 1992] [Zhao et al., 2004] [Tuazon and Atkinson, 1990] [Miyoshi et al., 1994] 3-methylfuran 3.6 +/- 0.4 4.4 +/- 0.6 4 +/- 2 < 2 [Atkinson et al., 1989] [Paulson et al., 1992] [Sprengnether et al., 2002] m/z 85 1.5 +/- 0.3 8.4 +/- 2.4e [Zhao et al., 2004] m/z 87 1.3 +/- 0.3 3.3 +/- 1.6f [Zhao et al., 2004] m/z 101 0.5 +/- 0.1 ~ 15%g 19.3 +/- 6.1h [Baker et al., 2005] [Zhao et al., 2004] aSum of yields of 3-seco-alpha-humulone aldehyde and 7-seco-alpha-humulone aldehyde, and alpha-humulal aldehyde, all with MW = 236. We did not observe m/z 237, but did observe m/z 219, its dehydrated fragment. bYield of 6-methyl-5-hepten-2-one (C8H14O = 126 amu). cYield of 4-hydroxy-2-methyl-5-hexen-1-al and its cyclized isomer (C7H12O2 = 128 amu). dLikely overestimated due to calibration issue. eYield of m/z 85 measured by PTR-MS and attributed to a C5 carbonyl (C5H8O = 84 amu). fYield of m/z 87 measured by PTR-MS and attributed to a C4 hydroxycarbonyl (C4H6O2 = 86 amu). gEstimated yield of two C5 hydroxycarbonyls. hYield of m/z 101 measured by PTR-MS and attributed to a C5 hydroxycarbonyl (C5H8O2 = 100 amu).