概括
基 (HO) 和一氧化碳 (CO) 之间的反应非常缓慢,速度常数小于10~20cm3/分子/秒. 这一发现表明HO(2) 反应在地球大气中并没有显著地将CO转化为CO(2).
科学领域:
- 大气化学 大气化学
- 摄影化学的使用.
- 化学动力学 化学动力学
背景情况:
- 一氧化碳 (CO) 是一个重要的大气污染物.
- 了解CO氧化途径对于大气建模至关重要.
- 氧基 (HO(2) 是大气氧化循环中的一个关键物种.
研究的目的:
- 为了确定反应 HO(2) + CO --> CO(2) + OH 的速率常数.
- 评估这种反应作为热层和平流层中二氧化碳的沉降池的重要性.
主要方法:
- 低强度光解CO,H(2) O,Ar和O(2) ((18,18) 的混合物.
- 测量CO2和CO2的光化学生产速率.
- 在300K时确定速率常数.
主要成果:
- 确定HO(2) + CO的速率常数为<= 10(-20) cm(3) /分子/秒在300 K时.
- 这种反应速度明显低于以前对大气条件的假设.
结论:
- 热化HO ((2) 与CO的反应对于CO转化为CO ((2) 在热层中是微不足道的.
- 这种反应途径在平流层中作为沉降机制也无关紧要.
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