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Yields of beta-hydroxynitrates, dihydroxynitrates, and trihydroxynitrates formed from OH radical-initiated reactions of 2-methyl-1-alkenes.

ABSTRACT: Yields of beta-hydroxynitrates, dihydroxynitrates, and trihydroxynitrates, in particles formed from OH radical-initiated reactions of C(9)-C(15) 2-methyl-1-alkenes in the presence of NO(x) were measured by using a thermal desorption particle beam mass spectrometer coupled to a high-performance liquid chromatograph with a UV-visible (UV-vis) detector. Yields of beta-hydroxynitrates and dihydroxynitrates increased with carbon number primarily due to enhanced gas-to-particle partitioning before reaching plateaus at approximately C(14)-C(15), where the compounds were essentially entirely in the particle phase. Plateau yields of beta-hydroxynitrates, dihydroxynitrates, and trihydroxynitrates were 0.183 +/- 0.005, 0.045 +/- 0.005, and 0.034 +/- 0.005, and, after normalization for OH radical addition to the C = C double bond, were 0.225 +/- 0.007, 0.055 +/- 0.006, and 0.042 +/- 0.006. The fractions of 1-hydroxy and 2-hydroxy beta-hydroxynitrate isomers were 0.90/0.10. Yields measured here and in our previous study of reactions of linear internal alkenes and linear 1-alkenes indicate that, for these alkene classes, the relative branching ratios for forming tertiary, secondary, and primary beta-hydroxyalkyl radicals by OH radical addition to the C=C double bond are 4.3/1.9/1.0, and the branching ratios for forming beta-hydroxynitrates from reactions of tertiary, secondary, and primary beta-hydroxyperoxy radicals with NO are 0.25, 0.15, and 0.12. The effects of H(2)O vapor and NH(3) on yields were also explored.

SUBMITTER: Matsunaga A

PROVIDER: S-EPMC2872378 | biostudies-literature | 2010 Apr

REPOSITORIES: biostudies-literature

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Yields of beta-hydroxynitrates, dihydroxynitrates, and trihydroxynitrates formed from OH radical-initiated reactions of 2-methyl-1-alkenes.

Matsunaga Aiko A Ziemann Paul J PJ

Proceedings of the National Academy of Sciences of the United States of America 20091231 15

Yields of beta-hydroxynitrates, dihydroxynitrates, and trihydroxynitrates, in particles formed from OH radical-initiated reactions of C(9)-C(15) 2-methyl-1-alkenes in the presence of NO(x) were measured by using a thermal desorption particle beam mass spectrometer coupled to a high-performance liquid chromatograph with a UV-visible (UV-vis) detector. Yields of beta-hydroxynitrates and dihydroxynitrates increased with carbon number primarily due to enhanced gas-to-particle partitioning before rea ...[more]

PMID: 20080570

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Dataset Information

Yields of beta-hydroxynitrates, dihydroxynitrates, and trihydroxynitrates formed from OH radical-initiated reactions of 2-methyl-1-alkenes.

Publications

Yields of beta-hydroxynitrates, dihydroxynitrates, and trihydroxynitrates formed from OH radical-initiated reactions of 2-methyl-1-alkenes.

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