Direct kinetics study of the product-forming channels of the reaction of isoprene-derived hydroxyperoxy radicals with NO

A direct kinetics study of the product-forming channels of the reaction of isoprene-derived hydroxyalkylperoxy radicals with NO has been performed at 100 Torr pressure and 298 K using the turbulent How technique with high-pressure chemical ionization mass spectrometry for the detection of reactants and products, For comparative purposes, a similar study was also performed for the reaction of 1- and 2-butene-derived hydroxyalkylperoxy radicals with NO. The measured hydroxyalkylnitrate product channel branching ratios were determined to be 0.061, 0.068, and 0.070 for the 1-butene, 2-butene, and isoprene systems, respectively. The results are compared to previous measurements of the hydroxyalkylnitrate-branching ratios for these systems, and the atmospheric significance of the results is discussed. (C) 2007 Wiley Periodicals, Inc. Int J Chem Kinet 39: 353-361, 2007.