Sources and fate of atmospheric organic nitrogen

大气有机氮的来源和去向

• 批准号: 418722-2012
• 负责人: Young, Cora
• 金额: $ 2.55万
• 依托单位: Memorial University of Newfoundland
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2017
• 资助国家: 加拿大
• 起止时间: 2017-01-01 至 2018-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=632891
• 关键词: Sources; fate; atmospheric; organic; nitrogen

Organic compounds can be released to the atmosphere through human activities or biological processes. These chemicals can be present in the gas or particle phase and can have important effects on the atmospheric and terrestrial environment, including climate and human health. In particular, organic compounds containing nitrogen can contribute to particle formation and act as a nitrogen input to nutrient-depleted areas. The role of organic nitrogen compounds in atmospheric processes is an emerging area of study and is poorly described. We will examine the sources and fate of organic nitrogen compounds through a combination of laboratory experiments and environmental sample analysis.A major source of nitrogenous organic compounds to the atmosphere is the ocean. Through wave action, chemicals present in the ocean can be lofted into the gas or particle phase. One area of study will be to conduct a full and analytically rigorous characterization of the different organic nitrogen species present in particles found in marine environments. We will also examine the role of ocean-atmosphere exchange as an atmospheric source of organic nitrogen compounds by simultaneously measuring ocean water, the sea-surface microlayer and marine particles. Through this research, we will be able to better understand how the ocean contributes to the overall atmospheric burden of organic compounds. Amines are one of the most commonly detected classes of atmospheric organic nitrogen compounds. These have been shown to contribute to new particle formation, though their gas-phase fate remains poorly characterized. We will investigate the gas-phase atmospheric fate of amines using smog chamber experiments. In particular, we will examine the likelihood for one particular reaction, N-dealkylation, and determine the mechanism by which it occurs in the gas phase.This research addresses critical areas of uncertainty in the field of atmospheric chemistry. Results of this work will improve knowledge of particle nucleation, composition, and radiative effects, which are essential to increasing our understanding of the impact of atmospheric composition on climate and health.

有机化合物可以通过人类活动或生物过程释放到大气中。这些化学物质可以气体或颗粒形式存在，对大气和陆地环境，包括气候和人类健康产生重要影响。特别是，含氮的有机化合物可以促进颗粒的形成，并作为营养枯竭地区的氮输入。有机氮化合物在大气过程中的作用是一个新兴的研究领域，描述很少。我们将通过实验室实验和环境样本分析相结合来研究有机氮化合物的来源和命运。大气中含氮有机化合物的主要来源是海洋。通过波浪作用，存在于海洋中的化学物质可以被抛入气相或颗粒相。研究的一个领域将是对海洋环境中发现的颗粒中存在的不同有机氮种类进行全面和严格的分析表征。我们还将通过同时测量海水、海面微层和海洋颗粒来研究海洋-大气交换作为有机氮化合物的大气来源的作用。通过这项研究，我们将能够更好地了解海洋如何对大气中有机化合物的总体负担做出贡献。胺是大气中最常检测到的有机氮化合物之一。这些已被证明有助于新粒子的形成，尽管它们的气相命运仍然不清楚。我们将利用烟雾室实验来研究胺的气相大气归宿。特别是，我们将检查一个特定反应的可能性，n -脱烷基，并确定其在气相中发生的机制。这项研究解决了大气化学领域中不确定的关键领域。这项工作的结果将提高对粒子成核、组成和辐射效应的认识，这对于增加我们对大气组成对气候和健康的影响的理解至关重要。