Criegeeの中間物質CH3CHOOOのコンフォーマル依存反応性の直接測定
Craig A Taatjes1, Oliver Welz, Arkke J Eskola
1Combustion Research Facility, Sandia National Laboratories, Livermore, CA 94551-0969, USA. cataatj@sandia.gov
Science (New York, N.Y.)
|April 13, 2013
まとめ
研究者は,より大きなCriegee中間物質であるメチル水酸化物 (CH3CHOO) の運動学を研究した. シンコンファーマーとアンチコンファーマーには異なる反応性が認められ,アンチCH3CHOOは水と二酸化硫黄に対してより反応性がある.
科学分野:
- 大気化学 大気化学
- 化学動力学 化学動力学
- 環境科学 環境科学
背景:
- クリーギーの中間物質 (カルボニル酸化物) は,熱帯圏の酸化において極めて重要です.
- 直接的な運動測定は,主に最も単純な形,CH2OO.に限られている.
研究 の 目的:
- 次の大きなCriegee中間物質であるメチル水酸化物 (CH3CHOO) の生成と反応動態を報告する.
- CH3CHOOのシンコンファーマーとアンチコンファーマーの異なる運動行動を調査する.
主な方法:
- CH3CHOOコンフォーマーの直接生産と特徴付け.
- SO2,NO2,H2Oとの反応速度の定数の測定.
主要な成果:
- シンとアンチCH3CHOOの両方がSO2とNO2と素早く反応する.
- Anti-CH3CHOOは,syn-CH3CHOOと比較して,水とSO2に対する反応性が著しく高い.
- 1.0 × 10^-14 ± 0.4 × 10^-14 cm^3 s^-1 の速度定数で,水と抗CH3CHOOの反応が測定されました.
結論:
- コンフォマー特異の反応性は,クリージー中間物質の大気運命を左右する.
- 水との反応は潜在的に支配的な除去経路であり,大気中の濃度に影響を与える.
- CH3CHOOの運動データは,大気中の酸化プロセスに関する重要な洞察を提供します.
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