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تسجيل مستخدم جديدPerformance of hybrid angle-energy dispersive X-ray diffraction and fluorescence portable system for non-invasive surface-mineral identification in Archaeometry
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Low power energy dispersive XRD-XRF portable instruments equipped with multiple angle scanning can take advantage of the shorter acquisition time of EDXRD with respect to ADXRD, and bring closer higher accuracy and resolution of inter-planar distance with those obtained by ADXRD. The data produced by this new hybrid configuration is correlated in the sense that a single XRF or XRD specimen appear in multiple spectra (the later shifted in energy for differing angles). Hence, for fully benefit from the richer data released by this configuration, the analysis should not be confined to the independent processing of the spectra, specialized hybrid data processing should be conceived. We previously reported some advances in the processing of the resulting 3D data (intensity, energy and angle). Here the analytical performance of the first hybrid angle-energy dispersive X-ray diffraction and fluorescence portable system is assessed for non-invasive surface mineral analysis of samples relevant for archaeometrical applications. We evaluate the performance on standard reference material and probe applicability of the methods so developed to identify stones (jadeite and omphacite), and pigments (Prussian blue) in the pictorial layer of modeled paintings. Discussion emphasize the improvement in accuracy of interplanar distance with respect to EDXRD taken at a single fixed angles, evaluate the resolution of AD/EDXRD data, and total acquisition time.
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