A new method of empirical calibration has been developed using matrix Ion species ratios to calibrate elemental sensitivity factors from external standards. A series of sensitivity factors Is generated as a function of sample chamber oxygen pressure using an oxygen leak system. The method Is applied to the analysis of three different metal matrices: steels, aluminum alloys, and copper alloys. The accuracy achieved with the method Is on the order of 10% relative error.
technique for quantitative analysis for trace amounts of arsenic. Comparison of detection limits (Table III) demonstrates that the ESCA-volatilization technique is quite competitive with other trace analytical methods. Likewise, our analytical method shows both good accuracy and precision.Further, volatilization can be performed in the field making remote sampling facile. The possibility of doing quantitative simultaneous multielement analysis at trace levels also has been demonstrated.
ACKNOWLEDGMENTThe authors express their gratitude to F. W. Plankey and E. M. Heithmar for loan of the atomic absorption standards and for some helpful discussions; also to S. Erickson for her assistance.
LITERATURE CITED(1) T. A. Carlson, "Photoelectron and Auger Spectroscopy", Plenum Press.
A computerized vidicon flame spectrometer is described along with Its application to a simultaneous determination of four serum electrolytes. Data acquisition, transfer, storage, and manipulation have been greatly improved by the computer addition. Operator input has been minimized while the programming has incorporated such features as automatic least-squares polynomial curve fitting, "spectral stripplng", background corrected peak signal measurements, and internal standard corrections.
Experimental N KVV Auger line shapes from sodium nitrate, produced by both x-ray (XEA) and electron (EEA) excitation, are compared to theoretically derived line shapes based on populations derived from a GTO-LCAO-Xα model. The one-electron orbital energies and valence line widths are determined from x-ray emission and photoelectron data; the Auger matrix elements are determined from experimental gas phase atomic Auger data. The theoretical Auger energies include hole–hole repulsion and relaxation. Theoretical lines shapes using the local and the Mulliken Xα populations are generated, and a set of empirical populations are also determined. This work emphasizes the importance of shake-off arising from creation of the initial core hole and its effect on the Auger line shape. A theoretical shake/Auger satellite line shape is generated and found to contribute up to 35% of the total intensity. The XEA and EEA line shapes (after correction for the sample and spectrometer transmission response) each show five features, but some differences are noted. These are attributed primarily to beam damage and charging effects on the EEA line shape. The theoretical line shapes reproduce the five principal features of the experimental spectra; specific features in the line shape are shown to reflect the relative size of the Auger matrix elements, the symmetry of the NO−3 ion, and satellite contributions. Arguments for the validity of a one-electron orbital model to describe the Auger line shape are presented.
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