在X射线光分析中评估衰减效应 矿物灰尘中光元素的分析
Xuan Liu1, Jay R Turner1, Dhruv Mitroo2,3
1Department of Energy, Environmental & Chemical Engineering, Washington University in St. Louis, St. Louis, Missouri 63130, United States.
概括
由于光元素衰减,X射线光 (XRF) 分析往往低估了矿物灰尘质量. 这项研究量化了这些影响,并提供了校正方程式,提高了颗粒物分析的准确性.
科学领域:
- 大气科学 大气科学
- 环境化学环境化学
- 分析化学 分析化学
背景情况:
- 准确的元素分析对于理解矿物尘埃的特性和大气影响至关重要.
- X射线光 (XRF) 测量可能会受到X射线衰减的影响,特别是对于光元素.
- 这种减弱往往导致低估了尘埃质量和不准确的成分在颗粒物 (PM) 分析.
研究的目的:
- 在矿物尘埃样本中实验量化和的X射线衰减.
- 开发和验证用于纠正基于XRF的减弱效应的经验方程.
- 评估这些校正对环境PM中的尘埃度估计的影响.
主要方法:
- 在特过器上空气化和收集二氧化,,亚利桑那州试尘 (ATD).
- 对已知成分的样本进行X射线光 (XRF) 和重力测量测量的比较.
- 基于质量负荷,粒子大小和元素组成的经验校正方程的开发.
主要成果:
- 随着样品质量加载和颗粒大小,X射线衰减增加.
- 与纯相比,在ATD中观察到较高的衰减,表明与其他地元素的协同作用.
- 现有的理论模型低估了测量的衰减;为Si和Al开发了经验方程.
- 将校正方程式应用于环境尘埃占主导地位的颗粒样本,使得尘埃度增加了21% (PM2.5) 和29% (PM10).
结论:
- 在矿物尘分析中,X射线衰减是影响轻元素量化的重要因素.
- 开发的经验方程为纠正XRF数据提供了更准确的方法.
- 实施这些校正对于从元素分析中可靠地确定尘埃质量和成分至关重要.
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