New Insights into the Formation and Evolution of Air Pollutants Via Atmospheric Multiphase Chemistry

通过大气多相化学对空气污染物的形成和演化的新见解

• 批准号: RGPIN-2018-03814
• 负责人: Zhao, Ran
• 金额: $ 2.11万
• 依托单位: University of Alberta
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2019
• 资助国家: 加拿大
• 起止时间: 2019-01-01 至 2020-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=683191
• 关键词: New; Insights; into; Formation; Evolution

Atmospheric aerosol refers to suspended particles with diameters 1/10 to 1/1000 that of an average human hair. Although small in size, aerosol exerts a huge impact on two of the arguably most emergent environmental issues of the 21st century: air pollution and climate change. Carrying harmful chemicals with it, aerosol can penetrate deep into the respiratory tract, affecting human health. In 2012, 7 million deaths worldwide were associated with ambient and indoor aerosol. Additionally, suspended aerosol can offset the warming effect of greenhouse gases by reflecting sunlight, which gives rise to a cooling effect on the planet. ******Understanding the chemistry of aerosol is currently a major scientific challenge. The toxicity and the magnitude of the aerosol cooling effect remain highly uncertain. One of the least understood aspects of aerosol is also a major fraction of it, referred to as Secondary Organic Aerosol (SOA), that contains hundreds of unidentified organic compounds produced through complex atmospheric chemistry. The research program proposed here aims to unravel the complex chemistry that leads to the formation and continuous evolution of SOA in the atmosphere. The outcome of the proposed research will guide the efforts of atmospheric chemists, environmental toxicologists and epidemiologists, as well as climatologists to better evaluate the environmental impact of aerosol. Such evaluations provide essential guidelines for policies, and ultimately, for a sustainable future. ******The proposed research program has two research directions. In the first direction, we will analyze the complex, unresolved fraction of SOA that is currently a major obstacle in understanding the SOA chemistry. We will develop innovative analytical methods for a direct measurement that avoids excess sample preparation and treatment, since delicate and reactive compounds can be lost during such processes. Employing both newly-developed and well-established analytical techniques, we will investigate the unidentified chemical species and undiscovered chemical reactions taking place in SOA. ******In the second direction, we will target an urgent environmental problem: air pollution from solid fuel burning. Solid fuel, including coal, firewood, agriculture residue and animal dung cake, is used by 3 billion people worldwide for cooking. Air pollution from solid fuel burning is the third most important health risk factor on the global scale. We will analyze the poorly understood chemical composition of aerosol arising from solid fuel burning. We will further study the atmospheric chemistry of emissions from solid fuel burning, which can give rise to toxic chemical pollutants and affect the air quality at a local to regional scale.

大气气溶胶是指直径为1/10至1/1000的悬浮颗粒。虽然规模很小，但气溶胶对21世纪的两个最新兴的环境问题产生了巨大影响：空气污染和气候变化。携带有害化学物质，气溶胶可以深入呼吸道，影响人类健康。 2012年，全球700万人死亡与环境和室内气溶胶有关。此外，悬浮的气溶胶可以通过反射阳光来抵消温室气体的变暖作用，从而产生对地球的冷却作用。 *****了解气溶胶的化学反应目前是一个主要的科学挑战。气溶胶冷却效果的毒性和大小仍然高度不确定。气溶胶最了解的方面之一也是其中的一小部分，称为二级有机气溶胶（SOA），其中包含数百种通过复杂的大气化学产生的未鉴定有机化合物。此处提出的研究计划旨在揭示导致SOA在大气中形成和连续发展的复杂化学反应。拟议研究的结果将指导大气化学家，环境毒理学家和流行病学家以及气候学家的努力，以更好地评估气溶胶的环境影响。这样的评估为政策提供了必要的准则，最终为可持续的未来提供了必要的指南。 *****拟议的研究计划有两个研究方向。在第一个方向上，我们将分析SOA的复杂，未解决的部分，这是当前了解SOA化学的主要障碍。我们将开发创新的分析方法，用于直接测量，以避免样品制备和处理过多，因为在此类过程中可能会丢失精致和反应性的化合物。采用新开发和建立良好的分析技术，我们将研究SOA中未鉴定的化学物种和未发现的化学反应。 ******在第二个方向上，我们将针对紧急的环境问题：燃油燃料的空气污染。全球30亿人使用固体燃料，包括煤炭，柴火，农业残留物和动物粪便蛋糕。固体燃料燃烧的空气污染是全球规模上第三大重要的健康风险因素。我们将分析固体燃料燃烧引起的气溶胶的知识不理的化学成分。我们将进一步研究固体燃料燃烧中排放的大气化学反应，这会导致有毒化学污染物，并在当地至区域尺度上影响空气质量。