オーガニックエアロゾールの構造のサイズ依存性
Daniel P Veghte1, Muhammad Bilal Altaf, Miriam Arak Freedman
1Department of Chemistry, The Pennsylvania State University , 104 Chemistry Building, University Park, Pennsylvania 16802, United States.
Journal of the American Chemical Society
|October 16, 2013
まとめ
大気化学と気候にとって極めて重要なエアロゾール粒子の相分離は,粒子のサイズに依存しています. より小さな粒子 (<170-270 nm) は分離されず,より大きな粒子は相分離を示します.
科学分野:
- 大気化学 大気化学
- 気候科学 気候科学
- マテリアルサイエンス 材料科学
背景:
- 異質な大気化学と気候の影響は,エアロゾール粒子の組成と構造によって影響を受けます.
- エアロゾール粒子内の化合物の内部配置を理解することは,その環境への影響を予測する鍵です.
研究 の 目的:
- モデル有機エアロゾール粒子の相分離行動を調査する.
- 混合アンモニア硫酸と有機酸エアロゾールの内部構造に対する粒子の大きさの影響を決定する.
主な方法:
- クリオ・トランスミッション電子顕微鏡 (cryo-TEM) を使用して,エアロゾール粒子の内部構造を視覚化しました.
- 試験されたモデルは,硫酸アンモニアと酸またはピメリック酸を混合した有機エアロゾールである.
主要な成果:
- リン酸混合物では170nm,ピメリック酸混合物では270nmより小さい粒子の相分離は観察されなかった.
- より大きなエアロゾール粒子は (>170 nm succinic acid, >270 nm pimelic acid) は相分離され,部分的に包囲された構造を示した.
結論:
- エアロゾール粒子の相分離は,粒子のサイズに大きく依存しています.
- サイズに依存する相分離は,エアロゾールと気候の相互作用と大気化学モデルに重大な影響を及ぼします.
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