Search results for "LIBS"

Integrated analytical methodologies for the study of corrosion processes in archaeological bronzes

2011

Abstract The investigations on structure and micro-chemical composition of archaeological metal alloys are needed in archaeometry. The aim of this study is devoted both to acquire information about their provenance and production technology, and to improve our understanding about the corrosion processes. In this paper we present the study of the corrosion phenomena of bronze samples, laboratory-made according to binary, ternary and quaternary alloys typical of Roman archaeometallurgical production through an integrated methodology based on the use of non or micro invasive physical techniques. Among the analysed samples, two were artificially aged through burial in the archaeological site of…

XRF and LIBS integrated analysis to identify the chemical composition and the conservation state of photographic and paper materials

2015

Time-gated Raman and laser-induced breakdown spectroscopy in mapping of eudialyte and catapleiite

2020

Raman analysis of rock samples containing rare earth elements (REEs) is challenging due to the strong fluorescence, which may mask the weaker Raman signal. In this research, time‐gated (TG) Raman has been applied to the construction of the mineral distribution map from REE‐bearing rock. With TG Raman, material is excited with a short subnanosecond laser pulse, and the Raman signal is collected within a picosecond‐scale time window prior to the formation of a strong fluorescent signal by means of single‐photon avalanche diode array. This allows signal readout with a significantly reduced fluorescence background. TG Raman maps are used to reveal the location of valuable minerals and are compa…

Development of direct elemental analysis for process control of nuclear materials manufacturing

2019

In order to optimize the quality control processes of uranium and plutonium metals from nuclear industry production lines, laser-induced breakdown spectroscopy (LIBS) appears as an efficient technique: it enables multi-element, fast and remote chemical analysis that require no sample preparation. Thus, the purpose of our work is to develop this technique towards the quantification of metal impurities in nuclear materials, with an analytical development achieved from surrogate materials. It follows another PhD thesis where a particular spectral band, Vacuum UltraViolet, has been chosen for its performance regarding the detection of several light elements in such materials. However, after per…

Testing a portable laser-induced breakdown spectroscopy system on geological samples.

2012

9 pages; International audience; This paper illustrates the potentialities of a home-made portable LIBS (laser-induced breakdown spectroscopy) instrument in Earth sciences, more particularly in geochemically recognizing (i) tephra layers in lacustrine sediments and (ii) fossilization processes in ammonites. Abundances for selected lines of Al, Ca, Fe, Ti, Ba and Na were determined in lacustrine chalk sediments of the Jura, where the Laacher See Tephra (LST) layer is recorded. A statistical treatment of elemental maps produced from the section of a sedimentary column containing the LST event allows instrumental conditions to be optimized. Accumulating spectra from close shot positions gives …

NDT for the detection and characterization of superficial treatments on stone material from archaeological sites of Merida (Spain)

2014

Studio integrato per la caratterizzazione dei laterizi

2008

Development of LIBS for online analysis of solid nuclear materials

2015

With the objective to implement a fast, online analysis technique for control of solid metal nuclear materials, laser-induced breakdown spectroscopy (LIBS) technique is developed for quantitative analysis in uranium and plutonium. Since these matrices have a very dense emission spectrum in the UV-Visible range, the Vacuum Ultra-Violet (VUV) spectral range, less rich in lines, is explored. The aim of this thesis is to perform the analytical development of VUV-LIBS for quantitative analysis between 500 and 5000 ppm with an uncertainty of 3%. For that purpose, four steps were defined. First, for practical and safety reasons, it is generally better to perform experiments on surrogate materials.…

LIBS analysis for a stratigraphic study on Cultural Heritage material

2015

Analisi integrata tramite XRF e LIBS per lo studio dei materiali pittorici

2011

Lo studio dei materiali pittorici è uno degli obiettivi primari per la caratterizzazione storico- artistica delle opere d’arte poiché fornisce informazioni utili circa i materiali originali e di degrado, la tecnica di esecuzione ed eventuali interventi di restauro pregressi. Tuttavia, la complessità delle indagini archeometriche è legata alla necessità di garantire la salvaguardia del bene culturale che rende essenziale l’uso di tecniche di indagini non o micro invasive. Tra le metodologie d’indagine integrata, l’uso della fluorescenza a raggi X (XRF) e della spettroscopia mediante ablazione laser (LIBS) risponde a tale esigenza e risulta particolarmente utile per la complementarietà delle …