模态α-烯氧化产物的分子性和云激活潜力
Aleia Bellcross1, Ariana Gray Bé1, Franz M Geiger1
1Department of Chemistry, Northwestern University, Evanston, Illinois 60208, United States.
Journal of the American Chemical Society
|October 4, 2021
概括
α-皮宁二次体中的性会影响它们的表面活动,影响云的形成. 这项研究将分子结构与大气气溶的云激活潜力联系起来.
科学领域:
- 大气化学
- 有机化学
- 气溶科学
背景情况:
- 二次有机气溶 (SOA) 由大气中挥发性有机化合物的氧化形成.
- SOA的物理和化学特性,如表面活性,影响气候和空气质量.
- 了解控制SOA表面活动的因素对于准确的气候建模至关重要.
研究的目的:
- 为了研究α-pinene衍生的二极体的表面活性.
- 确定立体化学和功能群对二元体表面活动的影响.
- 建立分子特性与云滴形成潜力之间的关系.
主要方法:
- 合成了十个大气相关的α-pinene衍生二元体.
- 测量合成二元体的表面活性.
- 确定了八醇-水 (Kow) 和八醇-硫酸盐 (Kas) 分割系数.
- 与表面活动测量相关的分区系数.
主要成果:
- 表面活性在二聚体之间有所不同,在二聚体之间观察到大约10%的差异.
- 增加的疏水性与更高的表面活性相关.
- 分割系数与表面活动测量一致.
- 证明骨干立体化学显著影响表面活动.
结论:
- 分子性在α-皮宁二次体的表面活性中起着关键作用.
- 分子性和二次有机气溶的云激活潜力之间存在直接联系.
- 结果表明对生物圈和大气层的反以及气溶颗粒的特性,如粘度和相位分离的潜在影响.
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