在费尔班克斯冬季的氧甲硫和硫 (IV) 在ALPACA研究期间
Kayane Dingilian1, Elliana Hebert1, Michael Battaglia1
1School of Earth and Atmospheric Sciences, Georgia Institute of Technology, Atlanta, Georgia 30332, United States.
ACS ES&T air
|July 18, 2024
概括
水氧甲硫酸盐 (HMS),一种甲-二氧化硫添加物,在寒冷的阿拉斯加气溶中含有很大一部分S (IV). 这项研究揭示了独特的寒冷天气水性化学物质影响气溶成分.
科学领域:
- 大气化学 大气化学
- 环境科学 环境科学
- 气溶科学 气溶科学
背景情况:
- 在阿拉斯加费尔班克斯极度寒冷期间,在微型气溶中发现高度的氧甲硫酸盐 (HMS).
- HMS是甲和二氧化硫的添加物,在液态水中形成,代表一个关键的S(IV) 物种.
- 以前的研究可能高估了HMS,因为它没有与其他S(IV) 化合物区分开来.
研究的目的:
- 在阿拉斯加分层污染和化学分析 (ALPACA) 研究期间调查气溶中的HMS度和S(IV) 种类.
- 开发和应用一种分离HMS的方法,以准确量化其对S的贡献.
主要方法:
- 开发一种使用过氧化的新型分析方法,专门隔离和量化HMS.
- 在Fairbanks的ALPACA密集研究中收集的总悬浮颗粒和PM2.5样本的分析.
- 描述S(IV) 种类,硫酸盐,温度和颗粒水含量,以了解形成途径.
主要成果:
- 在总悬浮颗粒中,HMS约占总S(IV) 的50%,在PM2.5.5中占70%.
- 未确定的S(IV) 种与HMS有很强的相关性,随着温度的降低而增加,并且对粒子水的依赖性很弱.
- 类似的HMS和未识别的S (IV) 的颗粒大小分布表明一种常见的水性形成过程.
结论:
- 有机S(IV) 物种,包括HMS和潜在的其他化物-S(IV) 添加物,在寒冷,污染的环境中独特的水化学中起着至关重要的作用.
- 在极度寒冷的条件下,超冷的液体颗粒促进了不同的化学途径,影响了气溶的组成.
- 需要进一步的化学表征来识别剩余的S(IV) 物种,并充分了解它们的形成和稳定性.
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