Search results for "X-Ray Fluorescence"
showing 10 items of 53 documents
Analysis of archaeological pottery by X-ray fluorescence spectrometry applying the limit dilution method
1994
A method for correcting the intensity of x-ray fluorescence (limit dilution method) is proposed for the analysis of samples with a complex matrix such as ceramic materials of archaeological interest. This method corrects the interelement effects, resolving the wide deviations which occur in the quantitative results obtained by x-ray fluorescence without correction. The contents of sodium, magnesium, aluminium, silicon, potassium, calcium, titanium and iron in sixteen archaeological ceramic samples of different origins and from different locations were determined. The results obtained are comparable to the values obtained by chemical analysis. A statistical study of the data was carried out …
The silver collection of San Gennaro treasure (Neaples): A multivariate statistic approach applied to X-ray fluorescence data
2021
Abstract In this work we report an X-ray fluorescence spectroscopy (XRF) study combined with a multivariate approach allowing to detect compositional differences and similarities among the alloys used in realization of silver collection of San Gennaro items collection. The San Gennaro treasure in Naples (Italy) represents, in fact, one of the most important silver collections in the world. The classification of the collection items is very complex, not only for the large number of objects, but also in consideration that between 1600 and 1700, in Naples, more than 350 laboratories were active, most of them specialized in specific art of work. As a consequence, a given collection object could…
Green direct determination of mineral elements in artichokes by infrared spectroscopy and X-ray fluorescence.
2015
Near infrared (NIR) and X-ray fluorescence (XRF) spectroscopy were investigated to predict the concentration of calcium, potassium, iron, magnesium, manganese and zinc in artichoke samples. Sixty artichokes were purchased from different Spanish areas (Benicarlo, Valencia and Murcia). NIR and XRF spectra, combined with partial least squares (PLS) data treatment, were used to develop chemometric models for the prediction of mineral concentration. To obtain reference data, samples were mineralised and analysed by inductively coupled plasma optical emission spectrometry (ICP-OES). Coefficients of determination obtained for the regression between predicted values and reference ones for calcium, …
Quantitative analysis of chromite ores using glass discs in moderate dilutions of lithium tetraborate by x-ray fluorescence spectrometry
2006
A method for the quantitative analysis of chromite ores by x-ray fluorescence spectrometry using beads is proposed. The work concerned the serious problems caused by the refractory nature of these materials which prevents the use of glass discs in x-ray fluorescence. An in-depth study was done to optimise the variables which influence the glass disc formation process. Sufficiently homogeneous glass discs were obtained under the following experimental conditions: lithium tetraborate as flux with moderate sample dilution (1:40), with the addition of one or two drops of LiBr solution(250 g l−1), at a temperature of 1200 °C for 30 min. The qualitative and semiquantitative results for the chromi…
Partial least squares modelization of energy dispersive X-ray fluorescence.
2019
As a proof of concept, a green methodology has been developed for the energy dispersive X-ray fluorescence (ED-XRF) determination of calcium, potassium, iron, magnesium, aluminum, chromium, strontium, phosphorus and nickel in the peel of untreated kaki fruit (Diospyros kaki. L) samples. ED-XRF spectra of fifty-six kakis purchased in the local area of LLombay (Valencia) were obtained directly from samples without any previous treatment and without sample damage just after cleaning the fruit with distilled water. Inductively Couple Plasma Optical Emission Spectrometry (ICP-OES) was used as a reference method to determine the mineral elements after microwave assisted acid digestion. XRF spectr…
La pittura vascolare attica a fondo bianco: la prospettiva archeologica, l'apporto dell'indagine scientifica
2017
Il presente contributo intende offrire nuovi spunti di ricerca sui vasi attici a fondo bianco e sulla relativa tecnica pittorica. In particolare, è stato selezionato come caso di studio il cratere del Pittore della Phiale (450-440 a.C.) con il mito di Perseo e Andromeda, esposto nel Museo Archeologico di Agrigento. La prima parte del lavoro si concentra sugli aspetti archeologici e storico-artistici, cercando di ricostruire il ruolo di questa tecnica nella produzione figurativa dell’artigiano e il rapporto tra il cratere di Agrigento e gli altri prodotti del Pittore della Phiale. Inoltre, viene considerata la connessione tra tecnica e con- testo di utilizzo e acquirenti o “committenti”, la…
Reconsidering the accuracy of X-ray fluorescence and ion beam based methods when used to measure the thickness of ancient gildings
2017
Since at least 5000 years ago, gilding techniques have been used for decoration purposes or to make artefacts appear as made of solid gold. Investigation of ancient gildings inevitably requires measuring their thickness, which is usually done either through the observation of cross-sections or by methods such as Rutherford backscattering spectroscopy, particle-induced X-ray emission and X-ray fluorescence. Whereas the former method requires sampling, the latter ones are non-invasive and therefore preferable. These non-invasive methods, however, measure the number of atoms per unit area, which can be converted into thickness only if the density is known. So far this has not been considered a…
Comparison of total-reflection X-ray fluorescence, static and portable energy dispersive X-ray fluorescence spectrometers for art and archeometry stu…
2004
Abstract In this paper, a Total-reflection X-ray Fluorescence (TXRF), a static and a portable Energy Dispersive X-ray Fluorescence (EDXRF) spectrometers are described. Both the equipments and the techniques employed in the field of the art and archeometry are compared. Some applications in this area are presented as well. The aim of the work is to know which spectrometer is the best suited depending on the work of art and the problem treated. The conclusion reached from the experience is that the portable EDXRF spectrometer is advisable to make “in situ” and online analysis in a multidisciplinary environment, the static EDXRF equipment is good to perform analysis on paper and metal pieces a…
Chemical fingerprint of outdoor PM2.5 in Malta
2015
Intro: RESPIRA (EU Funded - Italia-Malta 07-13) indicated that living in Malta is a risk factor for asthma. Aim: To determine the chemical profile of PM2.5 in Malta, and compare with reference values. Methods: Using FAI pumps at 10l/min/48hr, samples were collected on Teflon and Quartz filters from 6 schools and 46 homes in Malta. Total ICP-MS measurement (Residual+extracted), X ray Fluorescence, and thermo-optical methods(TO) were used for analysis by CNR in Rome. Aeroqual IQM60 counters were used for total PM2.5 mass. All data in ng/m3, Mean, (1st to 3rd quartile) of all 48 hour measurements.
DETERMINATION OF TWELVE TRACE ELEMENTS IN TWENTY-SEVEN AND TEN MAJOR ELEMENTS IN TWENTY-THREE GEOCHEMICAL REFERENCE SAMPLES BY X-RAY FLUORESCENCE SPE…
1992
This study reports the results of twelve trace elements in twenty-seven International geochemical reference samples (IGRS) (15 from Japan, 7 from South Africa, 4 from France and 1 from U.S.A.). Similarly, ten major elements were also determined in twenty-three GRS (15 from Japan, 5 from South Africa, 2 from France and 1 from U.S.A.). Whenever possible, the results are compared with literature values for these GRS.