ディメリックα-ピネンの酸化産物の分子キラリティと雲活性化ポテンシャル
Aleia Bellcross1, Ariana Gray Bé1, Franz M Geiger1
1Department of Chemistry, Northwestern University, Evanston, Illinois 60208, United States.
Journal of the American Chemical Society
|October 4, 2021
まとめ
α-ピネンジメのキラリティは,その表面活動に影響を与え,雲の形成に影響を与えます. この研究は,分子構造と大気中のエアロゾールの 雲の活性化の可能性を関連付けています
科学分野:
- 大気化学
- 有機化学
- エアロゾール科学
背景:
- 二次有機エロゾール (SOA) は,大気中の揮発性有機化合物の酸化によって形成される.
- 表面活動などのSOAの物理的,化学的性質は,気候と空気の質に影響します.
- SOAの表面活動を制御する要因を理解することは,正確な気候モデリングに不可欠です.
研究 の 目的:
- α-ピネン由来ジメールの表面活性を調べる
- 立体化学と機能群がダイマー表面活動に及ぼす影響を決定する.
- 分子特性と雲の滴の形成の可能性との関係を確立する.
主な方法:
- α-ピネン系ディメアを合成した.
- 合成されたダイマーの表面活性が測定された.
- オクタノール-水 (Kow) とオクタノール-アンモニアウム硫酸 (Kas) の分割係数
- 表面活動測定と相関する分割係数
主要な成果:
- 表面活性はディマーごとに変化し,約10%の差異がダイアステロエーマー間で観察されました.
- 表面活動と相関する水性の増加
- 分割係数は,表面活動測定値とよく一致しています.
- 背骨のステレオ化学が表面活動に 重要な影響を及ぼすことが示された.
結論:
- 分子キラリティはα-ピネン二重体の表面活性に重要な役割を果たします.
- 分子キラリティと二次有機エアロゾールの雲活性化の可能性の間には直接的なリンクが存在する.
- 生物圏と大気圏のフィードバックや,粘度や相分離などのエアロゾール粒子の特性への潜在的な影響を示唆しています.
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