气溶来源分配的不确定性与输入化学成分的选择有关
F Amato1, B L van Drooge1, J L Jaffrezo2
1Institute of Environmental Assessment and Water Research (IDAEA), Spanish National Research Council (CSIC), 08034 Barcelona, Spain.
Environment international
|January 19, 2024
概括
选择关键的化学标记剂对于使用正矩阵因子化 (PMF) 准确分配气溶源至关重要. 这项研究提供了建议,以减少PMF结果对常见城市污染源的不确定性.
科学领域:
- 环境化学环境化学
- 大气科学 大气科学
- 化学规格 化学规格 化学规格 化学规格
背景情况:
- 积极矩阵因子化 (PMF) 被广泛用于气溶源分配 (SA).
- 在PMF中选择输入化学成分的标准化程序缺乏.
- 不完整的化学表征可以显著影响SA结果和来源贡献估计.
研究的目的:
- 量化评估缺少特定源标记物的对PMF SA输出的影响.
- 为PMF分析中选择关键化学成分提供建议.
- 减少不确定性并改善城市常见PM来源的代表性.
主要方法:
- 对不同欧洲数据集 (地中海,大陆,阿尔卑斯山) 进行了三次敏感性分析.
- 包括扩展的有机标记剂套件,以覆盖不同的城市条件和PM分数.
- 评估了特定分析物对来源识别和贡献估计的影响.
主要成果:
- 车辆排气源的识别不那么敏感,但贡献率高达44%.
- 特定的无机元素对于非废气交通排放是必要的;非极地有机物对于分离废气和非废气因素至关重要.
- 和PAH对确定生物质燃烧至关重要;微量元素确定了航运和工业来源;主要/微量元素确定了矿物/土壤来源.
- 二次有机气溶 (SOA) 因素和真菌子/植物碎片需要特定的分子标记物.
结论:
- 化学成分的选择显著影响PMF SA的结果.
- 特定的标记物对于准确识别和量化各种颗粒物来源至关重要,包括生物质燃烧,交通,工业和生物源.
- 提供了建议,以提高基于PMF的来源分配研究的可靠性.
相关概念视频
Atomic Absorption Spectroscopy: Atomization Methods
514
Atomic Absorption Spectroscopy (AAS) atomizes samples through flame atomization or electrothermal atomization. Flame atomization typically involves a nebulizer and spray chamber assembly to combine the sample with a fuel–oxidant mixture, creating a fine aerosol mist that enters a burner. Typically, the fuel and oxidant are combined in an approximately stoichiometric ratio. However, for atoms that are easily oxidized, a fuel-rich mixture may be more advantageous. Only about 5% of the...
514
Propagation of Uncertainty from Systematic Error
521
The atomic mass of an element varies due to the relative ratio of its isotopes. A sample's relative proportion of oxygen isotopes influences its average atomic mass. For instance, if we were to measure the atomic mass of oxygen from a sample, the mass would be a weighted average of the isotopic masses of oxygen in that sample. Since a single sample is not likely to perfectly reflect the true atomic mass of oxygen for all the molecules of oxygen on Earth, the mass we obtain from this...
521
Atomic Absorption Spectroscopy: Interference
768
Interference leads to systematic error in atomic absorption (AA) measurements by enhancing or diminishing the analytical signal or the background. These interferences can be grouped into three main categories: spectral interference, chemical interference, and physical interference.
Spectral interference occurs when signals from other elements or molecules overlap with the analyte signal, falsely elevating or masking the analyte's absorbance. This interference can be corrected using Zeeman,...
Spectral interference occurs when signals from other elements or molecules overlap with the analyte signal, falsely elevating or masking the analyte's absorbance. This interference can be corrected using Zeeman,...
768
Atomic Emission Spectroscopy: Interference
192
In atomic emission spectroscopy (AES), high-temperature atomizers excite a broad range of elements and molecules that generate complex emissions from sources such as oxides, hydroxides, and flame combustion products in the flame or plasma. Several strategies can be employed to minimize spectral interferences caused by overlapping emission lines or bands. These include increasing instrument resolution, choosing alternative emission lines, optimally placing the detector in low-background regions,...
192
Sampling Plans
186
Sampling is a crucial step in analytical chemistry, allowing researchers to collect representative data from a large population. Common sampling methods include random, judgmental, systematic, stratified, and cluster sampling.
Random sampling is a method where each member of the population has an equal chance of being selected for the sample. It involves selecting individuals randomly, often using random number generators or lottery-type methods. For example, when analyzing the properties of a...
Random sampling is a method where each member of the population has an equal chance of being selected for the sample. It involves selecting individuals randomly, often using random number generators or lottery-type methods. For example, when analyzing the properties of a...
186
Atomic Emission Spectroscopy: Lab
163
AES is a powerful analytical technique, especially effective when used with plasma sources, producing abundant spectra in characteristic emission lines. The Inductively Coupled Plasma (ICP), in particular, yields superior quantitative analytical data due to its high stability, low noise, low background, and minimal interferences under optimal experimental conditions. However, newer air-operated microwave sources are emerging as promising alternatives that could be more cost-effective than...
163


