Dingilian Kayane, Hebert Elliana, Battaglia Michael, Campbell James R, Cesler-Maloney Meeta, Simpson William, St Clair Jason M, Dibb Jack, Temime-Roussel Brice, D'Anna Barbara, Moon Allison, Alexander Becky, Yang Yuhan, Nenes Athanasios, Mao Jingqiu, Weber Rodney J
School of Earth and Atmospheric Sciences, Georgia Institute of Technology, Atlanta, Georgia 30332, United States.
Geophysical Institute and Department of Chemistry & Biochemistry, University of Alaska Fairbanks, Fairbanks, Alaska 99775, United States.
ACS EST Air. 2024 May 15;1(7):646-659. doi: 10.1021/acsestair.4c00012. eCollection 2024 Jul 12.
Hydroxymethanesulfonate (HMS) in fine aerosol particles has been reported at significant concentrations along with sulfate under extreme cold conditions (-35 °C) in Fairbanks, Alaska, a high latitude city. HMS, a component of S(IV) and an adduct of formaldehyde and sulfur dioxide, forms in liquid water. Previous studies may have overestimated HMS concentrations by grouping it with other S(IV) species. In this work, we further investigate HMS and the speciation of S(IV) through the Alaskan Layered Pollution and Chemical Analysis (ALPACA) intensive study in Fairbanks. We developed a method utilizing hydrogen peroxide to isolate HMS and found that approximately 50% of S(IV) is HMS for total suspended particulates and 70% for PM. The remaining unidentified S(IV) species are closely linked to HMS during cold polluted periods, showing strong increases in concentration relative to sulfate with decreasing temperature, a weak dependence on particle water, and similar particle size distributions, suggesting a common aqueous formation process. A portion of the unidentified S(IV) may originate from additional aldehyde-S(IV) adducts that are unstable in the water-based chemical analysis process, but further chemical characterization is needed. These results show the importance of organic S(IV) species in extreme cold environments that promote unique aqueous chemistry in supercooled liquid particles.
在阿拉斯加高纬度城市费尔班克斯极端寒冷的条件下（-35°C），细气溶胶颗粒中的羟甲基磺酸盐（HMS）已被报道与硫酸盐一起存在显著浓度。HMS是S（IV）的一种成分，是甲醛和二氧化硫的加合物，在液态水中形成。以往的研究可能通过将HMS与其他S（IV）物种归为一类而高估了其浓度。在这项工作中，我们通过在费尔班克斯进行的阿拉斯加分层污染与化学分析（ALPACA）深入研究，进一步调查了HMS和S（IV）的形态。我们开发了一种利用过氧化氢分离HMS的方法，发现对于总悬浮颗粒物，约50%的S（IV）是HMS，对于细颗粒物（PM）则为70%。其余未鉴定的S（IV）物种在寒冷污染时期与HMS密切相关，随着温度降低，其浓度相对于硫酸盐有显著增加，对颗粒水的依赖性较弱，且粒径分布相似，这表明存在共同的水相形成过程。一部分未鉴定的S（IV）可能源自水基化学分析过程中不稳定的额外醛 - S（IV）加合物，但还需要进一步的化学表征。这些结果表明了有机S（IV）物种在极端寒冷环境中的重要性，这种环境促进了过冷液态颗粒中独特的水相化学。
