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水性酸盐的主要光动力学:过氧酸盐的形成
Dorte Madsen1, Jane Larsen, Svend Knak Jensen
1Department of Chemistry, University of Aarhus, Langelandsgade 140, DK-8000, Aarhus, Denmark.
Journal of the American Chemical Society
|December 11, 2003
概括
在200nm的水性酸盐离子 (NO3-) 的光化学反应主要产生cis-peroxynitrite. 一些兴奋的酸盐离子回到基本状态,而很小的一小部分分裂成NO和O2.
科学领域:
- 摄影化学的使用.
- 化学动力学 化学动力学
- 频谱学是一种光谱学.
背景情况:
- 水性酸盐离子 (NO3-) 是各种环境和生物系统中的重要组成部分.
- 了解它的光化学行为对于评估它的命运和影响至关重要.
研究的目的:
- 为了研究水性酸盐离子在200nm的紫外线照射后的主要光化学反应.
- 描述酸盐光解所涉及的过渡物种和反应途径.
主要方法:
- 采用5秒短暂吸收光谱,探测194-388nm范围内的反应.
- 高时间分辨率的测量允许对短寿命的光产品进行表征.
主要成果:
- 主要的光产品是过氧酸盐 (48%) 的cis-异构体.
- 激发的酸盐离子中有很大一部分 (44%) 在2 psi内放松到基本状态.
- 一个较小的途径 (8%) 涉及分离成NO和O2或相关物种.
结论:
- 在200nm的水性酸盐的初级光解中,主导作用是cis-peroxynitrite的形成.
- 缺少NO2和NO2表明,在以前的研究中,它们的形成是通过次要的,更长时间的反应发生的.
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