Surface sensitive studies on the heterogeneous photochemistry of multicomponent aerosols relevant to atmospheric environments

与大气环境相关的多组分气溶胶异质光化学的表面敏感研究

• 批准号: 327088-2011
• 负责人: AlAbadleh, HindA
• 金额: $ 2.55万
• 依托单位: Wilfrid Laurier University
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2015
• 资助国家: 加拿大
• 起止时间: 2015-01-01 至 2016-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=571920
• 关键词: Surface; sensitive; studies; heterogeneous; photochemistry

The lower atmosphere, or troposphere, comprises a large concentration of minute airborne particles known as aerosols. Atmospheric aerosols are emitted from natural sources (e.g. dust, sea salt), and from human activities (e.g. soot). They have complex chemical composition and they impact the global climate by influencing the amount of sunlight reaching the Earth's surface. Computer simulations of the climate give us the capability of quantifying the magnitude of aerosols' contribution to climate change. Yet aerosols' representation in these simulations is still inadequate, mainly because aerosols are complicated in nature and their reactivity and properties change with time. Thus, it is imperative to address scientific questions related to the chemistry of aerosols through experimental studies. The funding requested in this proposal will be used to tackle an important scientific problem, which is the role of solar radiation and metals in transforming organic matter in aerosols. The organic content of aerosols originates from pollution stemming from human activity, natural sources (emissions from trees and animals), and biomass burning. We will work with mimics of multicomponent aerosols composed of photoreactive chemicals and metals, and ubiquitous humic-like substances and amino acids. We will use experimental techniques that allow monitoring reactions on the surfaces of these materials under controlled environments, mimicking atmospheric conditions, so that results may be extrapolated to the "real world" system. Results obtained from these studies will increase our understanding of the role of photochemistry in modifying the chemical and physical properties of atmospheric particulate matter and its impact on gas phase species.

较低的大气或对流层包括大量的微分空气颗粒，称为气溶胶。大气气溶胶是从天然来源（例如灰尘，海盐）和人类活动（例如烟灰）发出的。 它们具有复杂的化学成分，并通过影响到达地球表面的阳光量来影响全球气候。 气候的计算机模拟使我们有能力量化气溶胶对气候变化的贡献的大小。然而，在这些模拟中，气溶胶的表示仍然不足，主要是因为气溶胶本质上是复杂的，其反应性和特性随时间变化。 因此，必须通过实验研究解决与气溶胶的化学有关的科学问题。 本提案中要求的资金将用于解决一个重要的科学问题，这是太阳辐射和金属在变化气溶胶中的作用。 气溶胶的有机含量源自人类活动，天然来源（来自树木和动物的排放）以及燃烧生物量的污染。 我们将使用由光电反应性化学物质和金属以及无处不在的腐殖质样物质和氨基酸组成的多组分气溶胶的模仿。 我们将使用实验技术，允许在受控环境下对这些材料的表面进行监视反应，模仿大气条件，以便将结果推断到“现实世界”系统。 从这些研究中获得的结果将增加我们对光化学在修饰大气颗粒物质的化学和物理特性及其对气相物种的影响的理解。