在污染的大气中从酸盐光解量化HONO生产量化
Yifan Jiang1, Men Xia1,2,3, Likun Xue4
1Department of Civil and Environmental Engineering, The Hong Kong Polytechnic University, Hong Kong 999077, China.
Environmental science & technology
|August 1, 2024
概括
研究人员纠正了颗粒酸盐光解测量中的"影子效应",揭示了更高的酸 (HONO) 生产率. 这项研究完善了对大气HONO来源的理解,这对于空气质量建模至关重要.
科学领域:
- 大气化学 大气化学
- 环境科学 环境科学
- 摄影化学的使用.
背景情况:
- 微粒酸盐 (pNO3-) 光解是热带层中酸 (HONO) 的潜在来源.
- 之前对光解速率常数 (jpNO3-) 的测量是不确定的,原因是"影子效应",即气溶层内的光灭绝会扭曲结果.
研究的目的:
- 开发和应用一种用于纠正pNO3-光解速率测量的阴影效应的新方法.
- 准确量化jpNO3-及其对冬季雾期间北中国平原HONO产量的影响.
主要方法:
- 采用了一种新技术,使用具有相同化学成分的气溶过器,但使用不同的气溶负载来纠正阴影效应.
- 经校正的jpNO3-被量化为在中国北方平原上的酸盐颗粒.
主要成果:
- 阴影效应校正显著增加了5°C的正常化平均jpNO3-从5.89 × 10^-6 s^-1增加到1.72 × 10^-5 s^-1.
- 修正后的jpNO3-随着PM2.5的pH和酸盐分数的增加而下降,与酸盐度没有相关性.
- 为大气模型开发了一个jpNO3-的参数化.
结论:
- 该研究提供了一种更准确的方法来确定pNO3-光解速率,这对于了解大气中的HONO生产至关重要.
- 这些发现对于改善空气质量模型至关重要,特别是在像北中国平原这样的地区,经历了重大的雾事件.
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