Sunlight Driven Chemistry in Aqueous Environments

在这个由美国国家科学基金会化学部环境化学科学项目资助的项目中，科罗拉多大学博尔德分校的Veronica Vaida教授研究了有机分子的阳光化学。该研究计划解决以下问题：水环境中阳光引发的化学在改变大气中的有机分子方面起什么作用？光化学反应如何影响海面分子和大气气溶胶粒子？以阳光为能量源，以水界面为反应介质的粒子形成的非生物机制是什么？实验室数据在多大程度上可以用来模拟现实的环境化学？通过回答这些问题，学生和博士后在大气化学方面获得了广泛的专业知识和技能。学生们由一个具有互补知识基础和技能的国际跨学科团队指导。研究者和跨学科国际合作者之间的科学交流大大拓宽了所有参与该项目的人的教育经验。这项工作导出了发生在不同相的大气光化学的分子水平机制和定量模型，包括气相和水相以及水的表面。这些光化学反应在大气气溶胶的形成和化学演化中发挥重要作用，对人类健康和气候变化具有潜在的重要影响。本研究考察了阳光引发、水介导的有机分子化学反应性的基本科学方面。通过实验室和理论研究的结合，研究的结果是提高了对发生在团簇和气溶胶表面的光化学反应的机制、动力学和速率的理解，这些反应在大气中具有重要意义。

In this project funded by the Environmental Chemical Sciences Program in the Chemistry Division at the National Science Foundation, Professor Veronica Vaida at the University of Colorado-Boulder studies the sunlight-initiated chemistry of organic molecules. The research program addresses the following questions: What role does sunlight-initiated chemistry in aqueous environments play in altering organic molecules in the atmosphere? How do photochemical reactions affect the molecules in the sea surface and atmospheric aerosol particles? What are the non-biological mechanisms for particle formation, which use sunlight as the energy source and aqueous interfaces as reaction media? To what extent can laboratory data be used to model realistic environmental chemistry? By answering these questions, students and postdoctoral fellows gain broad expertise and skills in atmospheric chemistry. The students are guided by an international and interdisciplinary team of colleagues with complementary knowledge base and skill sets. The scientific exchange between investigators and interdisciplinary international collaborators significantly broadens the educational experience of all those involved in this project.This work derives molecular-level mechanisms and quantitative models for atmospheric photochemistry that occur in different phases, including gaseous and aqueous phases and at the surface of water. These photochemical reactions play an important role in the formation and chemical evolution of atmospheric aerosols with potentially important consequences to human health and climate change. This investigation examines the basic scientific aspects of sunlight-initiated, water-mediated, chemical reactivity of organic molecules. Using a combination of laboratory and theoretical studies, the outcome of the research is an improved understanding of the mechanisms, dynamics, and rates of photochemical reactions occurring in clusters and on aerosol surfaces that are of importance in the atmosphere.