从实验室制备的和野火火炭中单一氧气量子产量产生热性溶解有机物质
Monika Madhiyan1, Kyle J Moor1
1Utah Water Research Laboratory, Department of Civil and Environmental Engineering, Utah State University, Logan, Utah 84322, United States.
Environmental science & technology
|December 29, 2023
概括
野火会释放出氧化溶解有机物 (pyDOM),在水中产生单片氧 (1O2). 大多数pyDOM具有类似的1O2产量,但高温焦炭的产量明显较低.
科学领域:
- 环境化学环境化学
- 摄影化学的使用.
- 有机地化学 有机地化学
背景情况:
- 野火和规定的火灾会释放出可燃性溶解有机物 (pyDOM).
- 通过光化学,PyDOM可以在阳光照明的表面水中产生单点氧 (1O2).
- 对于 pyrogenic DOM 的单一氧量子产量 (ΦΔ) 了解得很少,特别是从真正的野火样本和它们的波长依赖.
研究的目的:
- 为了确定来自野火和实验室准备的火柴的pyDOM的波长依赖的ΦΔ值.
- 为了比较PYDOM与非Pyrogenic DOM (SRNOM) 的ΦΔ值.
- 评估pyDOM对地表水光化学的影响.
主要方法:
- 时间分辨率的1O2光谱学.
- 从野火炭和实验室准备的木炭 (树和松树) 中生成的pyDOM的分析.
- 在各种激发波长下测量 ΦΔ 值.
主要成果:
- 与SRNOM (2.4%) 相比,野火和大多数实验室准备的pyDOM表现出类似的ΦΔ值 (2.12.7%在365nm).
- 从最高燃烧温度中获得的PyDOM显示,在所有激发波长中,ΦΔ值显著较低.
- 从pyDOM中预测的稳定状态1O2度与SRNOM相似.
结论:
- 来自大多数木炭的PYDOM具有与非燃烧性DOM相比的单一氧气生成潜力.
- 高温燃烧显著降低了pyDOM的1O2生产能力.
- 从木炭中添加pyDOM不太可能大幅改变地表水的光化学.
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