(北京有色金属研究总院, 北京 100088)
摘 要: 从X射线衍射强度的指数方程出发,考虑到1%的允许误差,经数学处理建立了微量薄膜样品的质量与衍射强度间的线性方程y=a+bIn; a, b值用被测物相纯样的外标曲线确定,线性方程的相关系数r=0.995, 从而建立了微量薄膜样品的物相定量分析直接对比法。同时,建立了微量样品和有限厚样品间临界值的实验方法及有限厚样品衍射强度的吸收校正方法。所建立的方法用于矿山呼吸性粉尘中α-SiO2的定量测定, 检出下限达0.01 mg。
关键字: 微量样品 物相定量分析 吸收校正 粉尘
(Beijing General Research Institute for Nonferrous Metals, Beijing 100088, P. R. China)
Abstract:The liner expressing equation correlating sample mass and the diffraction intensity, y=a+b In, was deduced mathematic ally from exponent equation of the X-ray diffraction intensity, with correlation coefficient r=0.995 and with one hundredth allowable error of quantitative phase analysis being taken into account. The values a and b are determined by an established calibration curve of measured phase. The direct contract method of quantitative phase analysis for trace-mass samples was established. The test method determining the critical values between the trace-mass samples and limited thickness samples and the absorption revision method of limited thickness samples were established. These methods have been used in determining the content of free silica of respirable dust and the evaluated limit can be downed to 0.01 mg.
Key words: trace-mass samples phase analysis absorption revision dust