Better air quality through chemistry: Real-time monitoring of reactive trace species in key atmospheric reactions impacting air quality

空气质量和气候是由大气中活性痕量物质的化学性质控制的。因此，我们理解、预测和设计改善空气质量和气候的政策的能力取决于我们对活性痕量物种化学的理解。在本项目中，您将学习Criegee中间体的化学，这是臭氧氧化不饱和挥发性有机化合物后在大气中产生的一类重要活性中间体。Criegee中间体在大气中反应迅速，对大气的氧化能力以及硫酸盐气溶胶和二次有机气溶胶的形成具有潜在的影响。然而，在这方面，由于缺乏关于Criegee中间体反应的动力学和产物产率的信息，对Criegee中间体在大气中的作用和影响的详细评估受到阻碍。您将开发在真实的微秒时间尺度上发生的反应过程中在实验室中直接和同时监测反应物和产物的能力-时间，并将其应用于克里奇中间体的关键大气反应的研究。您将联合收割机结合使用时间分辨宽带紫外吸收光谱和时间分辨红外量子级联激光（QCL）光谱在斯通集团开发，以实现这些目标，提供有关动力学和机制的Criegee中间体的大气成分，空气质量和气候的评估有价值的信息。您将有机会发展实验设计，动力学，光谱学，大气建模和数据分析方面的技能。您将开发可应用于各种问题的实验方法，包括大气化学，燃烧化学，天体化学和材料化学。

Air quality and climate are controlled by the chemistry of reactive trace species in the atmosphere. Our ability to understand, predict and design policies to improve air quality and climate, is thus dependent on our understanding of the chemistry of reactive trace species.In this project you will study the chemistry of Criegee intermediates, an important class of reactive intermediates produced in the atmosphere following the oxidation of unsaturated volatile organic compounds by ozone. Criegee intermediates react rapidly in the atmosphere, with potential impacts on the oxidising capacity of the atmosphere and formation of sulfate aerosol and secondary organic aerosol. However, detailed assessments of the role and impacts of Criegee intermediates in the atmosphere are hindered by a lack of information regarding the kinetics and product yields of Criegee intermediate reactions.You will develop capabilities for direct and simultaneous monitoring of reactants and products in the laboratory during the course of reactions taking place on microsecond timescales in real-time and apply this to studies of key atmospheric reactions of Criegee intermediates. You will combine the use of time-resolved broadband UV absorption spectroscopy and time-resolved infrared quantum cascade laser (QCL) spectroscopy developed in the Stone group to achieve these goals, providing valuable information on the kinetics and mechanisms of Criegee intermediates for assessments of atmospheric composition, air quality and climate. You will have opportunities to develop skills in experimental design, kinetics, spectroscopy, atmospheric modelling and data analysis. You will develop experimental methodology that can be applied to a wide range of problems including those in atmospheric chemistry, combustion chemistry, astrochemistry, and materials chemistry.