The gas phase atmospheric photolysis and reactions of key alkyl nitrates and their role in NOy partitioning.

硝酸烷基酯在控制整个对流层的二次有机气溶胶、臭氧、NOx、NOy和HOx的预算方面发挥着至关重要的作用，这些家庭在决定大气组成、地球辐射平衡和未来气候变化方面的重要性怎么强调都不过分。最近的一些区域和全球模型研究表明，缺少重要的动力学参数和光解参数，特别是生物挥发性有机化合物氧化形成的硝酸烷基酯的参数，使大气化学模型无法很好地描述氧化剂化学，从而无法确定关键温室气体和地表污染物的寿命。这些动力学和光解参数包括它们通过光解的损失率、通过与OH和O3反应的损失率以及NOx是否在与OH和O3反应时释放。在这项研究中，湍流化学电离质谱与气相色谱-电子捕获检测器（GC-ECD）结合用于检测硝酸烷基酯，将用于表征关键硝酸烷基酯与OH的反应动力学，而相对速率技术与GC-ECD和GC-ECD联用，MS将被用来验证不饱和有机硝酸盐与O3的反应动力学和最先进的闪光光解腔环系统的状态将被用来测量有机硝酸盐的光解和量子产率。这些数据将被纳入描述对流层的模型，并与现有的测量数据进行比较。拟议的工作对于了解生物挥发性有机化合物对大气污染和气候变化的影响至关重要。

Alkyl nitrates play a crucial role in controlling the budgets of secondary organic aerosols, ozone, NOx, NOy and HOx throughout the troposphere and the importance of these families in determining atmospheric composition, the earth's radiative balance and any future change in climate can not be overemphasised. A number of recent regional and global model studies have demonstrated that vital kinetic and photolytic parameters, especially for the alkyl nitrates formed from the oxidation of biogenic volatile organic compounds, are missing, preventing atmospheric chemical models from describing oxidant chemistry well and hence determining lifetimes of key greenhouse gases and surface pollutants. These kinetic and photolytic parameters include their loss rate via photolysis, loss rate via reaction with OH and O3 and whether NOx is released on reaction with OH and O3. In this study a combination of Turbulent-Flow Chemical Ionisation Mass Spectrometry coupled with a Gas chromatography- electron capture detector (GC-ECD) for the detection of alkyl nitrates will be used to characterise the kinetics of reaction with OH of key alkyl nitrates, whilst a relative rate technique coupled with GC-ECD and GC-MS will be used to characterise the kinetics of reaction of unsaturated organic nitrates with O3 and a state of the art flash photolysis cavity ring system will be used to measure the photolysis and quantum yield of organic nitrates. Such data will be incorporated into models describing the troposphere and compared with available measurements. The proposed work will be crucial to the understanding of the effects of biogenic volatile organic compounds on atmospheric pollution and climate change.