优化双室系统,用于直接测量臭氧生产速度
Yaru Wang1, Yi Chen2, Suzhen Chi1
1State Key Joint Laboratory for Environmental Simulation and Pollution Control, Center for Environment and Health, and College of Environmental Sciences and Engineering, Peking University, Beijing, 100871, China.
Environmental pollution (Barking, Essex : 1987)
|March 27, 2024
概括
使用双室系统直接测量臭氧生产率 (OPR) 为了解空气污染提供了一种新的方法. 这种优化的方法对城市环境具有足够的敏感性,有助于污染控制和光化学研究.
科学领域:
- 大气化学 大气化学
- 环境科学 环境科学
- 分析化学 分析化学
背景情况:
- 高臭氧生产率 (OPR) 有助于O3污染和对健康的负面影响.
- 现有的OPR观测和建模方法显示出差异,表明对臭氧光化学的理解不完全.
- 使用双室系统直接测量OPR (Mea-OPR) 是一种新的方法.
研究的目的:
- 优化用于直接OPR测量的双室系统 (Mea-OPR) 的设计.
- 在测量系统中量化和纠正光增强臭氧吸收.
- 评估系统在城市环境中的敏感性和适用性.
主要方法:
- 将室内表面积与体积比 (S/V) 缩小至9.8 m-1.1.
- 将O3的黑暗吸收系数降低到9.9 × 10−9.9.
- 进行了对照实验,以识别和量化光增强的O3吸收.
主要成果:
- 优化的Mea-OPR设计实现了面积与体积比为9.8 m-1的表面积和9.9 × 10−9.9的暗吸收系数.
- 确定并量化了显著的光增强臭氧吸收,需要对Mea-OPR进行修正.
- 具有±38%的测量不确定性和3.2 ppbv h-1 (3SD) 的检测极限,表明高灵敏度.
- 在2022年冬季奥运会期间,在北京城市测量了7.3 (±3.3,1SD) ppbv h-1的中午OPR.
结论:
- 优化的Mea-OPR系统对于城市和郊区的OPR测量具有足够的灵敏度.
- 开发的方法为评估污染控制政策提供了关键的观察数据.
- 这种直接测量技术将促进对臭氧光化学和空气污染的理解.
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