Comparison of fundamental parameters programs for quantitative X‐ray fluoréscence spectrometry

Abstract

Five readily available fundamental parameters x-ray spectrometry programs were compared for their performance in a more or less routine laboratory environment. The programs were used to determine a variety of elements in cement, geological samples, low-alloy steels, nickel alloys and plant material. All data were acquired using energydispersive x-ray spectrometry. Criteria used in the comparison include accuracy, versatility and ease of use. Performance is given in statistical summaries. LNTRODUCTIONAlthough quantitative x-ray spectrometry is a well established method, improved techniques for accurate analyses are still being sought. Measured x-ray intensities from a given element in a sample are frequently not linearly related to composition because of the influence of other elements in the matrix. It is necessary to correct analyte intensities for both absorption and enhancement by these concomitant elements. Matrix effects have traditionally been handled by multiple regression methods to obtain correction coefficients.'-' These correction coefficients are called alpha or influence coefficients and are often obtained from multiple regression of intensities against concentration of analyte and matrix elements in a suite of standards in which analyte concentrations bracket the range of interest. Because this approach is pragmatic, the resulting coefficients are frequently called empirical coefficients. Two common algorithms employed are known as the intensity correction model4 and the concentration correction model.' The concentration correction model uses the concentration of the analyte and matrix elements in the standards as the basis for the regression. If concentrations of non-analyte matrix elements are not known in the standards, the measured intensity of the matrix ele-

Energy-Dispersive X-ray Fluorescence Methods for Environmental Characterization of Soils

“…The algorithm calculates X-ray tube emission, absorption by sample, sample excitation, and self-absorption from theory, but empirically calibrates iteratively using standards (9,(11)(12)(13)(14). The algorithm calculates X-ray tube emission, absorption by sample, sample excitation, and self-absorption from theory, but empirically calibrates iteratively using standards (9,(11)(12)(13)(14).…”

X-Ray Fluorescence Spectrometry

“…(9), (10), and 12) and fundamental parameters for each element (attenuation coefficients, fluorescence yield, branching ratios) Several computer programs using the fundamental-parameter method have been described. Six packages are compared in [43].…”

Emprego da fluorescência de raios X por dispersão de energia para o mapeamento de troncos de árvores em Campinas, São Paulo

“…As concentrações elementares foram calculadas através do método de parâmetros fundamentais, um método absoluto bem estabelecido. 39 Finalmente, os mapas elementares foram construídos com as concentrações (micrograma/ grama) variando de acordo com a posição de amostragem (mm).…”