Electrochemistry reveals archaeological materials

The characterization of materials constituting cultural artefacts is a challenging step in their conservation, due to the object’s uniqueness and the reduced number of conservation institutes able to supply non-destructive analysis. We propose an alternative analytical tool, which combines accessibility (low cost and portable) and high sensitivity, based on electrochemical linear sweep voltammetry (LSV) with paraffin impregnated graphite electrode (PIGE). To investigate the composition of “white alloys” that certainly have been used as decoration on copper-based Roman fibulae, sampling was done very locally by gently rubbing the selected areas with the PIGE. LSV results evidence the presence of silver, lead, and tin, supporting the argument provided by typological analysis that these metals were used for decoration

Laser-Accelerated proton beams as diagnostics for cultural heritage

This paper introduces the first use of laser-generated proton beams as diagnostic for materials of interest in the domain of Cultural Heritage. Using laser-accelerated protons, as generated by interaction of a high-power short-pulse laser with a solid target, we can produce proton-induced X-ray emission spectroscopies (PIXE). By correctly tuning the proton flux on the sample, we are able to perform the PIXE in a single shot without provoking more damage to the sample than conventional methodologies. We verify this by experimentally irradiating materials of interest in the Cultural Heritage with laser-accelerated protons and measuring the PIXE emission. The morphological and chemical analysis of the sample before and after irradiation are compared in order to assess the damage provoked to the artifact. Montecarlo simulations confirm that the temperature in the sample stays safely below the melting point. Compared to conventional diagnostic methodologies, laser-driven PIXE has the advantage of being potentially quicker and more efficien

Nuclear Physics for Cultural Heritage

Nuclear physics applications in medicine and energy are well known and widely reported. Less well known are the many important nuclear and related techniques used for the study, characterization, assessment and preservation of cultural heritage. There has been enormous progress in this field in recent years and the current review aims to provide the public with a popular and accessible account of this work. The Nuclear Physics Division of the EPS represents scientists from all branches of nuclear physics across Europe. One of its aims is the dissemination of knowledge about nuclear physics and its applications. This review is led by Division board member Anna Macková, Head of the Tandetron Laboratory at the Nuclear Physics Institute of the Czech Academy of Sciences, and the review committee includes four other members of the nuclear physics board interested in this area: Faiçal Azaiez, Johan Nyberg, Eli Piasetzky and Douglas MacGregor. To create a truly authoritative account, the Scientific Editors have invited contributions from leading experts across Europe, and this publication is the combined result of their work. The review is extensively illustrated with important discoveries and examples from archaeology, pre-history, history, geography, culture, religion and curation, which underline the breadth and importance of this field. The large number of groups and laboratories working in the study and preservation of cultural heritage across Europe indicate the enormous effort and importance attached by society to this activity

Development of Quantitative Methods to Study PFAS Using Proton Induced Gamma-Ray Emission

Per- and polyfluoroalkyl substances (PFAS) are man-made chemicals that have become a major environmental concern. They can be found in a broad range of everyday products and pose a significant risk to the public due to their adverse health effects. They are persistent, bioaccumulate and do not break down in the environment. This project specifically aims to determine the concentration of Fluorine, a key identifier of PFAS, in environmental samples. To do this, we employ proton induced gamma-ray emission (PIGE) to screen for Fluorine within our samples. PIGE is performed at the Union College Ion Beam Analysis Laboratory using a 1.1-MV tandem Pelletron accelerator. Samples are bombarded in an ex-vacuo setup with an incident energy of 1.8 MeV and emitted gamma-rays are detected with a high-purity Ge detector. This research defines two quantitative methods for PIGE analysis. The first uses standards of known concentrations to compare to collected samples. The second uses a developed python application to directly compute concentration values based on nuclear theory. We present preliminary results on the accuracy of both methods

Savanyú vulkáni üvegek ásványtan-geokémiai vizsgálata, petrológiai és vulkanológiai kiértékelése = Mineralogical and geochemical study of acid volcanic glasses, and its interpretation from petrological and volcanological point of view

Változatos lemeztektonikai környezetben képződött obszidián minták fő- és nyomelemtartalmának összehasonlító vizsgálata során megállapítottuk, hogy az eredetileg gránitokra kidolgozott diszkriminációs diagramok alkalmazhatók a savanyú kiömlési kőzetek esetében is. Megállapítottuk, hogy az óceáni sziget bazaltok (OIB) és a szigetív mészalkáli bazaltok (IAB) chondritra normált spiderdiagramjainak néhány alapvető jellegzetessége (pl. a relatív Nb-Ta minimum, ill. relatív Nb-Ta maximum) az obszidiánminták spiderdiagramjának patternjénél is felismerhető. Vizsgáltuk a mikro-PIXE elemzések megbízhatóságát és felhasználhatóságát, s bemutattuk, hogy az ezzel a módszerrel készített piroxénelemzési eredmények alkalmasak geotermometriai számítások elvégzésére. Savanyú vulkáni üvegek mállási folyamatát riolittuffa mintákon vizsgáltuk. A minták ásványos és főelem-összetételének valamint termoanalitikai paramétereinek (TG) összehasonlítása alapján megállapítottuk, hogy a mállási fok jellemzésére egyes TG paraméterek a nemzetközi gyakorlatban elterjedt indexhez (CIA) hasonló megbízhatósággal rendelkezik. Részt vettünk egy olyan berendezés kifejlesztésében, ami magas hőmérsékleten direkt mintavételt tesz lehetővé tömegspektrometriai vizsgálatokhoz. E berendezést vulkáni üvegek termális bomlási folyamatainak tanulmányozásánál is hasznosítani lehet. | Major and trace element spectra of obsidian samples from various tectonic settings were performed by LA-ICP-MSand PIGE techniques. The results suggest that discrimination diagrams for granites may be used for acidic volcanic rocks, too. We found that some characterisctic patterns of chondrite normalised spider diagram of OIB and IAB (such as relative Nb-Ta minimum and relative Nb-Ta maximum, respectively) can be observed in the case of obsidians, too. We demonstrate that analytical data yielded by micro-PIXE measurements can be applied even for geothermometric estimations. Weathering process of acidic volcanic glasses was studied on rhyolite tuff samples. Comparing mineralogical and major element composition as well as some thermoanalytical parameters of the samples it can be stated on the basis of some TG parameters weathering degree of rhyolite tuffs can be determined with a reliability that similar to that of the internationally accepted CIA index. We participated in construction of high temperature direct probe coupled to a quadrupole MS. This device can be also used for monitoring thermal decomposition of volcanic glasses

Une plateforme pour l'analyse de matériaux par faisceaux d'ions à ARRONAX : Etude de l'effet d'humidité sur les échantillons

International audienceQuantification of soil pollution with method based on X-ray detection like X-Ray Fluorescence(XRF) suffers of multiple bias (moisture, surface state) especially when it's used for insituanalysis using portable-XRF. In order to study the effect of moisture on the results of ananalysis performed using X-Ray, we have performed studies using high energy PIXE/PIGE atthe ARRONAX. Samples were made of sand of different type. High energy PIXE/PIGE allowsus to avoid bias from surface state and to focus on moisture effect. It also allows to assessthe chemical composition of the sample. Results show a different behavior for each elementpresent in volcanic sand.</p

Li distribution characterization in Li-ion batteries positive electrodes containing LixNi0.8Co0.15Al0.05O2 secondary particles

The elemental distribution of as-received (non-charged) and charged Li-ion battery positive electrodes containing LixNi0.8Co0.15Al0.05O2 (0.75 ? x ? 1.0) microparticles as active material is characterized by combining μ-PIXE and μ-PIGE techniques. PIGE measurements evidence that the Li distribution is inhomogeneous (existence of Li-rich and Li-depleted regions) in as-received electrodes corresponding with the distribution of secondary particles but it is homogeneous within the studied individual secondary micro-particles. The dependence of the Li distribution on electrode thickness and on charging conditions is characterized by measuring the Li distribution maps in specifically fabricated cross-sectional samples. These data show that decreasing the electrode thickness down to 35 μm and charging the batteries at slow rate give rise to more homogeneous Li depth profiles

Industrial Applications of Laser Neutron Source

The industrial applications of the intense neutron source have been widely explored because of the unique features of the neutron-matter interaction. Usually, intense neutron sources are assembled with fission reactors or high energy ion accelerators. The big size and high cost of these systems are the bottle neck to promote the industrial applications of intense neutrons. In this paper, we propose the compact laser driven neutron source for the industrial application. As the first step of our project for the versatile applications of laser driven neutron source, Li-neutron and/or Li-proton interactions have been investigated for the application to the development of Li battery