Search results for " EDX"

Obsidian in the Upper Palaeolithic of Iberia

2021

Submitted by André Pereira (andrepereira@letras.ulisboa.pt) on 2021-07-28T13:04:08Z No. of bitstreams: 1 obsidian-in-the-upper-palaeolithic-of-iberia.pdf: 35662679 bytes, checksum: 4c261781e3211c52c02d47cc36e26d98 (MD5) Approved for entry into archive by Manuel Botelheiro Moreno (manuelmoreno@campus.ul.pt) on 2021-07-28T16:31:42Z (GMT) No. of bitstreams: 1 obsidian-in-the-upper-palaeolithic-of-iberia.pdf: 35662679 bytes, checksum: 4c261781e3211c52c02d47cc36e26d98 (MD5) Made available in DSpace on 2021-07-28T16:32:40Z (GMT). No. of bitstreams: 1 obsidian-in-the-upper-palaeolithic-of-iberia.pdf: 35662679 bytes, checksum: 4c261781e3211c52c02d47cc36e26d98 (MD5) Previous issue date: 2021 info:eu…

Un disco-coraza de hierro de la Bastida de les Alcusses (moixent, valencia)

2017

Se presenta un disco-coraza de hierro procedente del oppidum ibérico de la Bastida de les Alcusses documentado con motivo de la revisión completa de los hallazgos de las excavaciones realizadas entre 1928 y 1931. La pieza es una lámina seudocircular en cuyo perímetro se distribuyen unos pequeños remaches para suspender el disco a las correas de sujeción, realizadas probablemente en cuero. Después de presentar el disco y los resultados de las analíticas EDXRF que permiten identificar los metales utilizados en la producción del disco (hierro) y los remaches (plata y cobre), se analiza su contexto de hallazgo, se encuadra históricamente esta categoría de armamento defensivo. Finalmente, se int…

Comparative Study of PM10 Concentrations and Their Elemental Composition Using Two Different Techniques during Winter–Spring Field Observation …

2022

The aims of this study were to determine the concentrations and elemental composition of PM10 in the village of Kotórz Mały (Poland), to analyse their seasonal variability, to determine the sources of pollutant emissions and to compare the consistency of the results obtained using different methods. Sampling and weather condition measurements were carried out in the winter (January–February) and spring (April) of 2019. Two combinations of different techniques were used to examine PM10 concentrations and their chemical composition: gravimetric method + atomic absorption spectrometry (GM+AAS) and continuous particle monitor + energy dispersive X-ray fluorescence (CPM+EDXRF).…

Portable non invasive analyses for Cultural Heritage

2014

The requirements that the scientific analyses for Cultural Heritage must have are: nondestructive and noninvasive, multielemental, sensitive, reliable and sufficiently rapid, able to carry out measurements in situ on objects of all types, and to deduce information practically on-line. Among the techniques that fulfill these requirements we find: multispectral imaging, portable EDXRF, Raman and UV-VIS-NIR spectrometry. In this paper we are going to show some cases in which it will appear clear the necessity of the correct order with which applying the non invasive techniques and what data of each of them it is necessary to understand in situ to obtain the maximum of the subsequent scientific…

Low-Q peak in X-ray patterns of choline-phenylalanine and homophenylalanine: a combined effect of chain and stacking

2016

Abstract In this contribution we report for the first time the X-ray patterns of choline-phenylalanine and choline-homophenylalanine ionic liquids. The presence of a low Q peak in both systems is another evidence that a long alkyl chain is not always needed to establish a nanodomain segregation in the liquid sufficient to be revealed by the diffraction experiment. These new data are compared with the diffraction patterns and the theoretical calculations of other choline-aminoacid ionic liquids recently reported. A significant role might be played by the stacking interactions between aromatic rings.

Energy dispersive X-ray diffraction potentiality in the field of cultural heritage: simultaneous structural and elemental analysis of various artefac…

2007

The applicability of an Energy Dispersive X-ray Diffractometer to some technical questions in the field of Cultural Heritage is presented. This diffractometer, equipped with a white source, has been utilized for the structural and elemental analysis of some items having different nature. Given its design, the instrument allows to collect data from samples as big as a book or a little more. Samples, without collection of any portion and without any preliminary preparation, have been placed in the instrument and spectra have been collected in a wide energy range that contains X-ray fluorescence and diffraction features. In all cases, data acquired in air and in a non destructive way were reli…

EDXRF analysis of the Pentecost Triptych from the “São Pedro de Miragaia” church (Porto, Portugal)

2013

Abstract EDXRF spectrometry was used to determine the pigment composition of the Pentecost Triptych, a Flemish masterpiece located at the Church of Sao Pedro de Miragaia (Porto, Portugal). The triptych was restored at the beginning of the 20th century and presents a great number of zones with repaints and colour alterations that can be observed on the whole of their surface. The identification of the original pigments and restoration pigments was based on their characteristic colour and the correlation between the detected elements and the named “key elements” of ancient pigments (Ca, Fe, Cu, Hg, Pb,…) and modern pigments (Ti, Ba, Cr, Zn, Co, Cd,…). The analysis of the triptych has been car…

Chitosan-heteropolyacid complex as high performance membranes for low temperature H2-O2 fuel cell

2014

Hybrid organic-inorganic membranes for low temperature H2-O2 fuel cell

2014

Characterization of prehispanic cosmetics found in a burial of the ancient city of Teotihuacan (Mexico)

2012

The present paper reports the chemical data obtained on samples of pigmenting materials contained in 31 miniature vessels found in a burial found in Teopancazco, a multiethnic neighborhood center located in the southeastern sector of the archaeological site of Teotihuacan (Central Mexico) and the analytical protocol established for the complete characterization of these archaeological materials. For this purpose a multi-technique approach based on the combination of several non destructive and micro-destructive instrumental techniques, namely, light microscopy (LM), scanning electron microscopy-X-ray micro-analysis (SEMe EDX), transmission electron microscopy (TEM), voltammetry of micropart…