6533b824fe1ef96bd1280157

RESEARCH PRODUCT

Quantitative electron probe microanalysis of metallic oxide mixtures applying an empirical calibration technique

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Abstract An analytical procedure is proposed for the independent quantitative chemical analysis of each element in the presence of other elements in the matrix of a sample by Energy Dispersive Electron Probe Microanalysis. For this purpose, an empirical calibration technique (which we shall call here the JABO method), which studies the variation of the X-ray intensities in terms of the analyte concentration in a chemical system with a complex matrix, is established. The methodology consists of the modification of the unknown sample by addition of a diluent, an internal standard and the analyte itself (dilution-addition method). A mathematical model is proposed to calculate the K parameters for the analyte ( K i ) and standard ( K p ) in each sample. A series of glass discs for each analyte are prepared which make it possible to obtain experimental values of characteristic X-ray lines. Some new K parameters are defined as K i and K p quotients, which remain constant in a wide concentration range. This allows us to use them for the calculation of the component concentrations of the unknown sample, as reproducing mathematical expressions between X-ray intensity and analyte concentration are obtained. An algorithm is proposed to calculate the component concentration in a sample with a complex matrix where components exist with a strong interelemental interaction effect. The method has been applied satisfactorily to the determination of titanium (accuracy 3%) and zinc (accuracy 0.5%) in the presence of a large proportion of zirconium which acts as interferent.