吸収された窒素酸塩の光化学
Jennifer Schuttlefield1, Gayan Rubasinghege, Mohamed El-Maazawi
1Department of Chemistry, University of Iowa, Iowa City, Iowa 52246, USA.
Journal of the American Chemical Society
|August 30, 2008
まとめ
ミネラルダストエアロゾルの上の窒素は光分解され,窒素酸化物を生成します. 共同吸収された水と酸素は,製品分布に影響を与え,大気化学に影響を与えます.
科学分野:
- 大気化学 大気化学
- フォトケミストリー フォトケミストリー
- 表面科学とは,地表科学のことである.
背景:
- 窒素酸化物は大気中の粒子と反応し,吸い込まれる窒素酸塩を形成する.
- エアロゾールの表面に吸収された窒素の光化学は十分に理解されていません.
- ミネラルダストと海塩のエアロゾールは,大気中の重要な成分です.
研究 の 目的:
- アルミナ (鉱物粉末の代用物質) に吸収された窒素の光分解を調査する.
- 共同吸収された水と分子酸素が窒素光化学に及ぼす影響を決定する.
- エアロゾール表面の光化学反応における相対湿度の役割を理解する.
主な方法:
- 窒素吸収アルミニウムをブロードバンド光 (λ > 300 nm) で照射する.
- 低 (<1%RH) と高 (45%RH) の相対湿度で実施された実験.
- 質量スペクトロメトリを用いたガス相産物 (NO2,NO,N2O) の分析.
主要な成果:
- 窒素光分解は,あらゆる条件下でNO2,NO,およびN2Oを生成します.
- 共同吸収された水と分子酸素は,製品の分布を変化させます.
- NOは,O2 (乾燥と湿気) が存在しない場合の主な産物です.
- NO2は,O2の存在における主要な産物である.
結論:
- この研究は,固体界面における吸附物質の光化学における水の役割を初めて調査したものです.
- 水,酸素,および相対湿度は,エアロゾール表面の窒素光化学を著しく影響する.
- エアロゾールのこれらの光化学的プロセスは,大気中の化学的バランスを変化させることができます.
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