ZAFG 球形粒子定量表征方法:推导出几何校正的通用方程
Seyed Mahmoud Bayazid1, Nicolas Brodusch1, Nicolas Dumaresq1
1Department of Mining and Materials Engineering (Wong Building), McGill University, 3610 Rue University, Montreal, Quebec, H3A 0C5, Canada.
概括
一个新的通用方程准确计算了用于量化球形粒子的几何校正因数 (G). 这一因素取决于粒子大小和X射线范围,简化了小样本的X射线微分析.
科学领域:
- 材料科学 材料科学 材料科学
- 分析化学 分析化学
- 物理 物理学 物理
背景情况:
- 在电子探针微分析 (EPMA) 中精确量化小粒子是具有挑战性的.
- 传统的ZAF方法需要对原子数,吸收和光效应进行校正.
- 为了准确分析球形粒子,需要几何校正因数 (G).
研究的目的:
- 为X射线微分析中的几何校正因子 (G) 开发一个通用方程.
- 用NIST-K411玻璃微球验证拟议的G因子模型.
- 为了研究G因子对粒子大小和X射线发射范围的依赖性.
主要方法:
- 为几何校正因子 (G) 开发一个理论模型.
- 在碳基板上对NIST-K411玻璃微球进行实验量化.
- 模型预测与实验数据的比较.
主要成果:
- 几何校正因子 (G) 最好用粒子直径 (D) 和X射线范围 (Xe) 的函数来建模.
- 在预测的G因子和实验结果之间观察到出色的一致性.
- 当 Xe > D 时,G 因子在指数级下降,这与光束能量和组成无关.
- 当 D*Xe > 1 时,粒子将表现为 G = 1 的批量样本.
结论:
- 为几何校正因子 (G) 提出的通用方程为球形粒子提供了准确的量化.
- G因子主要取决于粒子直径和X射线范围 (D*Xe) 的乘积.
- 这种模型简化了EPMA中小颗粒的分析,减少了对成分和光束能量的依赖.
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