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On the north coast of present-day Peru, between the Andes and the Pacific Ocean, approximately between 100 and 600 ad, the Moche civilization prospered. The Moche were very sophisticated artisans and metal smiths, so that they are considered the finest producers of jewels and artifacts of the region. Their metalworking ability was impressively demonstrated by the excavations of the tomb of the 'Lady of Cao' (dated around third-fourth century ad) discovered by Regulo Franco in 2005. Impressive is the beauty of the artifacts, and also the variety of metallurgical solutions, demonstrated by not only the presence of objects composed of gold and silver alloys but also of gilded copper, gilded silver, and tumbaga, a poor gold Cu-Au alloy subject to depletion gilding. About 100 metal artifacts from the tomb of the Lady of Cao, never before analyzed, were studied by using various portable equipments based on following non-destructive and non-invasive methods: energy-dispersive X-ray fluorescence with completely portable equipments;, transmission of monenergetic X-rays;, radiographic techniques; and, optical microscopy., Gold objects and gold areas of nose decorations are characterized by approximately the same composition, that is, Au = (79.5 ± 2.5) %, Ag = (16 ± 3) %, and Cu = (4.5 ± 1.5) %, while silver objects and silver areas of the same nose decorations show completely erratic results, and a systematic high gold concentration. Many gilded copper and tumbaga artifacts were identified and analyzed. Further, soldering gold-silver was specifically studied by radiographs. Additional measurements are needed, particularly because of the suspect that depletion gilding was systematically employed also in the case of some nose decorations. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The present study utilized the new hard X-ray microspectroscopy beamline facility, X27A, available at NSLS, BNL, USA, for elemental mapping. This facility provided the primary beam in a small spot of the order of ∼10 μm, for focussing. With this spatial resolution and high flux throughput, the synchrotron-based X-ray fluorescent intensities for Mn, Fe, Zn, Cr, Ti and Cu were measured using a liquid-nitrogen-cooled 13-element energy-dispersive high-purity germanium detector. The sample is scanned in a 'step-and-repeat' mode for fast elemental mapping measurements and generated elemental maps at 8, 10 and 12 keV, from a small animal shell (snail). The accumulated trace elements, from these biological samples, in small areas have been identified. Analysis of the small areas will be better suited to establish the physiology of metals in specific structures like small animal shell and the distribution of other elements. [ABSTRACT FROM AUTHOR]

Abstract: On the north coast of present-day Peru flourished approximately between 50 and 700 AD, the Moche civilization. It was an advanced culture and the Moche were sophisticated metalsmiths, so that they are considered as the finest producers of jewels and artefacts of the region. The Moche metalworking ability was impressively demonstrated by the objects discovered by Walter Alva and coworkers in 1987, in the excavations of the “Tumbas Reales de Sipán”. About 50 metal objects from these excavations, now at the namesake Museum, in Lambayeque, north of Peru, were analyzed with a portable equipment using energy-dispersive X-ray fluorescence. This portable equipment is mainly composed of a small size X-ray tube and a thermoelectrically cooled X-ray detector. Standard samples of gold and silver alloys were employed for quantitative analysis. It was determined that the analyzed artefacts from the “Tumbas Reales de Sipán” are mainly composed of gold, silver and copper alloys, of gilded copper and of tumbaga, the last being a poor gold alloy enriched at the surface by depletion gilding, i.e. removing copper from the surface. [Copyright &y& Elsevier]

Abstract: In this study, synchrotron-based micro-beam was utilized for elemental mapping of a small animal shell. A thin X-ray spot of the order of ∼10μm was focused on the sample. With this spatial resolution and high flux throughput, the X-ray fluorescent intensities for Ca, Mn, Fe, Ni, Zn, Cr and Cu were measured using a liquid-nitrogen-cooled 13-element energy-dispersive HpGe detector. The sample is scanned in a ‘step-and-repeat’ mode for fast elemental mapping and generated elemental maps at 8, 10 and 12keV. All images are of 10μm resolution and the measurement time was 1s per point. The accumulation of trace elements was investigated from the soft-tissue in small areas. Analysis of the small areas will be better suited to establish the physiology of metals in specific structures like small animal shell and the distribution of other trace elements. [Copyright &y& Elsevier]

Energy-dispersive X-ray fluorescence (EDXRF) has been used successfully for some time now in non-destructive diagnostic examinations of art works, especially for paintings and bronze works. Furthermore, such examinations may be carried out with portable equipment, allowing studies in situ . EDXRF-analysis of paintings generally provides the following information:–possible presence of elements on the surface (sulphur, chlorine) due to pollution;–identification of the elements, and therefore giving a good indication of the pigments, employed by the artist; and–identification of previous restoration areas, by detecting the presence of “modern” elements, such as titanium, zinc, cadmium, etc. Recently, the famous Chapel of the Scrovegni painted by Giotto in Padua in 1303–1305 was analysed in detail to obtain all the information described above. Another example of application of EDXRF-analysis to paintings was a recent examination of 11 paintings believed to be by De Chirico the outcome of which was compared with that obtained for 15 paintings certainly by De Chirico. Finally, the bronze statue of Bartolomeo Colleoni was analysed, in order to determine its composition and the presence of sulphur and chlorine on the surface. In this case, the analysis was partially destructive, because small areas of a few square millimetres had to be cleaned for analyses, to avoid interference by the patina. [ABSTRACT FROM AUTHOR]

Total L X-ray fluorescence cross sections have been measured in the atomic region 39≤Z≤51 excited by 5.47, 6.47, 7.04, 7.57, 8.14, 8.74 and 9.36 keV photons. Experimental cross sections are compared with the theoretical estimates of Chen et al. based on relativistic Dirac-Hartree–Slater theory. Good agreement is observed between experimental results and theoretical estimates in the studied atomic and energy region. Experimental fluorescence yields have been evaluated using the experimental fluorescence cross sections and theoretical subshell photoionization cross sections. Fluorescence yields are fitted by least squares to fifth-order polynomials in Z of the form ∑[sub T10n] a[sub n] z[sup n] and compared with theoretical and earlier fitted values. The deviation of the average fluorescence yield in the atomic region 46≤Z≤51 with new theoretical estimates of ū[sub L] , calculated using the ECPSSR (Energy loss Coulomb deflection Perturbed Stationary State Relativistic effects) theory of Brandt and Lapicki and the fitted values clearly indicate the weak dependence of the average fluorescence yield on the initial vacancy distribution. [ABSTRACT FROM AUTHOR]

Soil and radish (Raphanus Sp) samples from areas treated with organic compost of recyclable urban garbage were quantitatively analyzed by using tube-excited energy-dispersive X-ray fluorescence analysis. Soils treated with 10, 20 and 30 t/ha of recyclable urban garbage and control soil were analyzed. The layer soils were collected at 0–5, 5–10, 10–20, 20–40, 40–60 cm depth. It was possible simultaneously to determine the elemental concentration of various elements: K, Ca, Ti, Mn, Fe, Cu, Zn, Br, Rb, Sr, Zr and Pb in recyclable urban garbage, soil treated with organic compost of recyclable urban garbage and radish plants cultivated in these soils. The elemental concentration of K, Ca, Ti and Fe were determined at percent level (macro-elements) and the other elements at ppm level (micro-elements). It was also possible to observe a significant increase in the contents of K, Ca, Zn, Rb, Sr, Zr and Pb in the soil treated in comparison with the control soil and it was also verified whether the transport of these elements to radish plants cultivated in these soils occurred. [Copyright &y& Elsevier]