Comparison of Two Sample Preparation Methods for X‐Ray Fluorescence Spectrometry in the Determination of Ni and Cr |
| |
| Authors: | Surendra P Verma Rosalinda González‐Ramírez Rodolfo Rodríguez‐Ríos |
| |
| Institution: | 1. Departamento de Sistemas Energéticos, Centro de Investigación en Energía, Universidad Nacional Autónoma de México, Priv. Xochicalco s/no., Col Centro, Apartado Postal 34, Temixco 62580, Mexico;2. Posgrado en Ingeniería, Centro de Investigación en Energía, Universidad Nacional Autónoma de México, Priv. Xochicalco s/no., Col Centro, Apartado Postal 34, Temixco 62580, Mexico |
| |
| Abstract: | Pressed powder pellets and fused beads or glass disks are routinely used in X‐ray fluorescence spectrometry for the determination of major and trace elements, respectively, in geological materials. In order to evaluate the performance of these two sample preparation methods, we determined Ni and Cr concentrations of fourteen RMs from Japan, France and South Africa, and eighty‐five igneous and three sedimentary rock samples from Mexico in both powder pellets and glass beads. We also computed new values of statistical parameters for RMs from an outlier‐based multiple‐test method and compared them with the literature mean and confidence limit values. The results showed that the multiple‐test method provided more reliable central tendency and dispersion parameters for RMs than those obtained previously from the two or three standard deviation method, or from robust methods. The powder pellet and fused bead sample preparation methods provided consistent results for Ni and Cr at concentration levels > 50 μg g?1 in this application; for lower concentration levels, however, these methods showed somewhat greater differences. For quantitative comparisons, both ordinary and weighted least‐squares linear regression models were used to show that the two sample preparation methods provided generally unbiased results. |
| |
| Keywords: | reference material robust methods outlier‐based methods X‐ray fluorescence spectrometry weighted least‐squares linear regression ordinary least‐squares linear regression Maté riaux de ré fé rence mé thodes robustes mé thodes des valeurs aberrantes spectromé trie de fluorescence de rayons X ré gression liné aire par mé thode des moindres carré s pondé ré s ré gression liné aire par mé thode des moindres carré s ordinaires |
|
|
