Search results for "X-Ray Fluorescence"
showing 10 items of 53 documents
Multi-elemental determination of heavy elements in plastics using X-ray fluorescence after destruction of the polymer by molten sodium hydroxide
1992
In this paper a method is proposed for the multielemental analysis of Sb(III), Ba, Cd, Cr(III), Hg, Pb and As(III) in plastics, using X-ray fluorescence after alkaline decomposition and preconcentration by (co)precipitation. The organic matrix is destroyed by decomposition with sodium hydroxide melted in a silver crucible by the open system technique, using sodium nitrate as auxiliary oxidant. The variables which influence preconcentration are optimized: digestion time, pH, salinity, carrier and sodium diethyldithiocarbamate (DDTC) and sodium rhodizonate (R) as precipitants. The calibration curves were linear up to 200 μg of the element present, except for lead (150 μg) antimony(III) (100 μ…
Conservation Work on an Ancient Sicilian Processional Banner: Preliminary Analyses and in Situ Restoration
2013
Abstract Before carrying out the conservation work on the gilded wooden frame of the processional banner coming from Tusa, Sicily, some preliminary diagnostic analyses were conducted in order to identify materials that made up the wooden frame. After a micro-sampling phase, a thin section of the wooden support allowed to identify the timber as linden wood (basswood). The X-Ray Fluorescence analysis confirmed the presence of a thin layer of primer made of plaster and animal glue covered with a red bolus primer, used for the gilding process. The restoration was carried out during the opening hours of the museum, allowing visitors to be informed on the restoration phases.
Double Laser LIBS and micro-XRF spectroscopy applied to characterize materials coming from the Greek-Roman theater of Taormina
2009
The laser-induced breakdown spectroscopy (LIBS) is an applied physical technique that has shown, in recent years, its great potential for rapid qualitative analysis of materials. The possibility to implement a portable instrument that perform LIBS analysis makes this technique particularly useful for in situ analysis in the field of cultural heritages. The aim of this work is to compare the results, obtained by LIBS measurements with X-Ray Fluorescence (XRF) ones, on calcareous and refractory materials coming from the Greek-Roman theater of Taormina. Calibration curves for LIBS and XRF were obtained by measuring certified reference materials and using them as standards. LIBS measurements we…
Direct determination of minerals in human diets by infrared spectroscopy and X-ray fluorescence
2014
The use of near and mid infrared spectroscopy and X-ray fluorescence (XRF) to determine the concentration of mineral elements in Spanish human diets was investigated. Thirty-five commercial baby foods, 6 children fast food menus and 13 university canteen menu samples were analysed by infrared and XRF spectroscopy and spectra evaluated by using reference data obtained by inductively coupled plasma optical emission spectroscopy (ICP-OES). Models for calcium, potassium, iron, magnesium, sodium and zinc determination were built and validated. Spectra were pre-treated by using different pre-processing algorithms (multiplicative scatter correction, standard normal variation, first derivate, ortho…
Klimt artwork: red-pigment material investigation by backscattering Fe-57 Mössbauer spectroscopy, SEM and p-XRF
2017
Material tests were performed on a rediscovered Klimt-artwork "Trompetender Putto". We performed studies on the red colored spots, mainly taken from non-restored parts. MIMOS II Fe-57 Mossbauer spectroscopy (novelty in art-pigment analysis) mainly reveals haematite and crystallized goethite in red colors. Electron microscopy can identify various layers of the original and overpainting of an artwork. The number of layers fluctuates between three and four chemically painted areas. The portable X-ray fluorescence analysis enables to reduce the pigment list to containing mercury (cinnabar), lead, zinc, iron and titanium. Infrared-light-irradiation visualizes the different age of the pigments.
Study and dating of medieval ceramic tiles by analysis of enamels with atomic absorption spectroscopy, X-ray fluorescence and electron probe microana…
2002
Abstract This paper reports an analytical study of enamel on fragments of medieval tiles using atomic spectroscopy techniques — AAS, XRF and SEM/EDX. The samples came from a hermitage in the region of Valencia (Spain) and have different motifs, mainly floral ones in a wide variety of colors. A study of the soluble salts in the biscuits and mortar was carried out using AAS to determine their present capacity to produce efflorescence and the type of efflorescence. XRF was used to identify the oxides responsible for the different colors and the pigments used over large areas of the tiles (white and green). SEM/EDX was used to characterize the white and green and smaller areas of other colors. …
Evaluation of the interelemental effect in X-ray fluorescence analysis by the total addition method
1992
An algorithm for quantifying interelemental effects in X-ray fluorescence techniques is developed. By applying an addition process, the ratio between the mass absorption coefficients of the analyte and the unknown sample (μi*/μs*) is calculated to correct the fluorescence intensity of the element to be determined and linearize the I-c calibration plot. This coefficient can be calculated graphically and numerically. The method is applied to the determination of tin in lead alloys with good results over wide concentration ranges.
A radiometric and petrographic interpretation of discrepancies on uranium content in samples collected at Alte Madonie Mounts region (Sicily, Italy)
2013
Abstract The main goal of this work is to evaluate a correlation between anomalous Uranium (U) content and petrographic features of some soil and rock samples collected at Alte Madonie Mounts region (North-central Sicily, Italy). A total of 41 samples of selected soils and rocks were collected, powdered, dried and sealed in “Marinelli” beakers for 20 days before the measurement to ensure that radioactive equilibrium between 226 Ra and 214 Bi was reached. Gamma-ray spectrometric analysis was used to quantify radioactivity concentrations. Mineralogical and chemical features of the samples were determined by X-ray Fluorescence (XRF), X-ray Diffractometry (XRD), Attenuated Total Reflection-Four…
Interface Solid-State Reactions in La0.8Sr0.2MnO3/Ce0.8Sm0.2O2 and La0.8Sr0.2MnO3/BaCe0.9Y0.1O3 Disclosed by X-ray Microspectroscopy
2019
The stability of the electrode/electrolyte interface is a critical issue in solid-oxide cells working at high temperatures, affecting their durability. In this paper, we investigate the solid-state chemical mechanisms that occur at the interface between two electrolytes (Ce0.8Sm0.2O2, SDC, and BaCe0.9Y0.1O3, BCY) and a cathode material (La0.8Sr0.2MnO3, LSM) after prolonged thermal treatments. Following our previous work on the subject, we used X-ray microspectroscopy, a technique that probes the interface with submicrometric resolution combining microanalytical information with the chemical and structural information coming from space-resolved X-ray absorption spectroscopy. In LSM/BCY, the …
Double pulse laser induced breakdown spectroscopy applied to natural and artificial materials from cultural heritages
2009
Abstract The laser-induced breakdown spectroscopy (LIBS) is an applied physical technique that has shown in recent years its great potential for rapid qualitative analysis of materials. Thanks to the possibility to implement a portable instrument that perform LIBS analysis, this technique is revealed to be particularly useful for in situ analysis in the field of cultural heritages. The purpose of this work is to evaluate the potentiality of LIBS technique in the field of cultural heritages, with respect to the chemical characterization of complex matrix as calcareous and refractory materials for further quantitative analyses on cultural heritages. X-Ray Fluorescence (XRF) analyses were used…