Environmental Photochemistry at the Air-Ice Interface

加州大学戴维斯分校的Cort Anastasio教授和Davide Donadio教授受到化学系环境化学科学项目的资助，研究发生在冰雪表面的化学反应。雪含有多种化学污染物，其中一些是有毒的。人们最初认为，沉积在雪中的污染物会被保存下来，但最近的研究表明，这些化学物质可以被阳光降解。这些光化学反应可以去除雪中的有毒污染物。然而，它们也会产生有毒物质，其中一些会释放到空气中。不幸的是，对这些过程的理解是有限的，部分原因是研究很少。但现有的研究也存在一个差异：一些研究报告称，阳光在雪中的反应比在水中更快，而另一些研究则没有发现差异。在这个项目中，对条件（如雪、冰）如何影响光化学的理解正在研究中。同时，对加快雪光化学反应的机制的理解也在考虑之中。这些目标正在通过实验室实验和雪上化学污染物的建模相结合来实现。这个项目包括向公众宣传，强调化学对日常生活的影响。它还包括K-12学校的活动，以及本科生和研究生的培训。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

Professors Cort Anastasio and Davide Donadio of the University of California at Davis are funded by the Environmental Chemical Sciences Program in the Division of Chemistry to study chemical reactions that take place on the surfaces of ice and snow. Snow contains a variety of chemical contaminants, some of which are toxic. It was originally thought that contaminants in deposited snow are preserved, bit recent work shows that these chemicals can be degraded by sunlight. These photochemical reactions can remove toxic contaminants from the snow. However, they can also make toxic products, some of which are released to the air. Unfortunately, understanding of these processes is limited, in part because there are few studies. But there is also a discrepancy in the existing studies: some report that sunlight reactions are faster in snow than in water, while other studies find no difference.In this project, an understanding about how conditions (e.g., snow, ice) impact photochemistry are being investigated. As well, an understanding about the mechanisms responsible for making snow photochemistry faster are being considered. These goals are being pursued with a combination of laboratory experiments and modeling of chemical contaminants on snow. This project includes outreach to the public, highlighting the impact of chemistry on everyday life. It also includes activities at K-12 schools, and the training of undergraduate and graduate students.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.