大気中の水酸化物 (ROOOH) の形成
Torsten Berndt1, Jing Chen2, Eva R Kjærgaard2
1Atmospheric Chemistry Department (ACD), Leibniz Institute for Tropospheric Research (TROPOS), 04318 Leipzig, Germany.
まとめ
大気中の有機水酸化物 (ROOOH) は,有機過酸化物 (RO2) と水酸化物 (OH) から直接形成される. 以前は見過ごされていたこの物質のクラスは,地球全体の形成率と短い大気中の寿命を持っています.
科学分野:
- 大気化学
- 有機化学
- 環境科学
背景:
- 有機三酸化物 (ROOOH) は,有機合成で使用される強力な酸化物質です.
- 以前の推論では,有機ペロキシラジカル (RO2) とヒドロキシラジカル (OH) のガス相反応による大気形成が示唆されていた.
研究 の 目的:
- 大気中の有機三酸化物 (ROOOH) の形成を直接観察する.
- RO2 + OH反応の運動を調査する.
- ROOOHの大気形成率とインパクトを定量化する.
主な方法:
- 大気に関与するROOHの形成の直接観測
- RO2 + OH反応の運動分析
- ROOOHの収穫を予測するために,イソプレンの分解のグローバルモデリング.
主要な成果:
- 直接観測により,RO2 + OH反応からROOOHの形成が確認された.
- 反応速度の係数は衝突限界に近いことが判明した.
- グローバルモデリングは,イソプレンの分解から最大1%のモラー水酸化物産出を予測し,年間約1000万トンに達した.
- ROOOHの大気中の寿命は 数分から数時間です
結論:
- 有機三酸化物 (ROOOH) は,大気中の化合物の新しく特定された重要なクラスである.
- 急速な形成と実質的な収穫は,大気への影響のさらなる検討を必要とします.
- ROOOHは,以前は大気化学モデルで省略された成分を表しています.
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