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1. The Sedimentary Origin of Black and White Banded Cherts of the Buck Reef, Barberton, South Africa

Author: Morgane Ledevin, Nicholas Arndt, Catherine Chauvel, Etienne Jaillard, and Alexandre Simionovici
Subjects: chert, archean, buck reef, sediment, geochemistry, climate, Geology, QE1-996.5
Abstract: The Buck Reef is a 250−400 m thick sequence of banded black and white (B&W) cherts deposited ca. 3416 Ma ago in a shallow basin. We provide field, petrological and geochemical constraints on the chert-forming process and the origin of the banding. White layers consist of nearly pure microquartz, while black layers are mixed with detrital carbonaceous matter, quartz grains and carbonaceous microlaminae, interpreted as remnants of microbial mats. The circulation of Si-rich fluid is recorded by abundant chert veins and pervasive silicification. However, the high purity of the white layers, their lack of internal structures and extremely low Al, Ti and high-field-strength elements preclude an origin by silicification of sedimentary or volcanic precursors. Moreover, their reworking at the surface into slab conglomerates, and sediment-like contacts with black layers rule out a diagenetic origin. We propose a new model whereby the white layers were periodically deposited as precipitates of pure silica; and the micro-layering within the black layers formed by annual temperature fluctuations, favouring microbial activity in summer and inorganic silica precipitation in winter. Outcrop-scale alternation of B&W layers was associated with major, thousand-year-long climate events: white cherts represent massive silica precipitation resulting from changes in ocean circulation and temperature during cold intervals.
Published: 2019
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2. Fossil Bioapatites with Extremely High Concentrations of Rare Earth Elements and Yttrium from Deep-Sea Pelagic Sediments

Author: Alain Manceau, Sophie A. L. Paul, Alexandre Simionovici, Valérie Magnin, Mélanie Balvay, Nathaniel Findling, Mauro Rovezzi, Samuel Muller, Dieter Garbe-Schönberg, Andrea Koschinsky, Centre National de la Recherche Scientifique (CNRS), Institut des Sciences de la Terre (ISTerre), Institut national des sciences de l'Univers (INSU - CNRS)-Institut de recherche pour le développement [IRD] : UR219-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Gustave Eiffel-Université Grenoble Alpes (UGA), Observatoire des Sciences de l'Univers de Grenoble (OSUG ), and Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Grenoble Alpes (UGA)-Météo-France
Subjects: Atmospheric Science, Space and Planetary Science, Geochemistry and Petrology, [SDU.ENVI]Sciences of the Universe [physics]/Continental interfaces, environment
Abstract: Detailed geochemical and mineralogical insights into some of the richest rare earth elements and yttrium (REY)-containing bioapatites from ocean-floor sediments have been provided by combining laser ablation inductively coupled plasma diffraction analysis, and Ce L3-edge high energy-resolution X-ray absorption near edge structure (HR-XANES) spectroscopy. Bioapatites at 1.94 and 4.70 m below the seafloor (mbsf) of the Clarion-Clipperton Zone (CCZ) of the Pacific Ocean have 26,600 (RSD = 15.7%, n = 20) and 30,300 (RSD = 14.6%, n = 10) mg/kg (mg/kg) total REY, respectively, and bioapatites at 2.28 and 6.95 mbsf of the Peru Basin have 15,500 (RSD = 15.6%, n = 20) and 15,700 (RSD = 17.8%, n = 29) mg/kg total REY, respectively. All bioapatite specimens have a variety of isomorphic substitutions in all atomic positions of the crystallographic structure. The average crystallochemical formula of bioapatites at 6.95 mbsf of the Peru Basin is [(PO4)2.71(SiO4)0.04(CO3,SO4)0.25][Ca4.57Na0.29Y0.04][F0.87Cl0.21]. All other substituents are below 0.04 atoms per formula unit. HR-XANES provides the first direct evidence for trivalent Ce in sediment apatites. The strong negative geochemical anomaly of Ce in fossil bioapatites is well explained by the occurrence of four valent Ce-MnO2 and CeO2 within the sediment and in seafloor ferromanganese nodules.
Published: 2022
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3. Crystal Chemistry of Thallium in Marine Ferromanganese Deposits

Author: Alain Manceau, Alexandre Simionovici, Nathaniel Findling, Pieter Glatzel, Blanka Detlefs, Anna V. Wegorzewski, Kira Mizell, James R. Hein, Andrea Koschinsky, Institut des Sciences de la Terre (ISTerre), Institut national des sciences de l'Univers (INSU - CNRS)-Institut de recherche pour le développement [IRD] : UR219-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Gustave Eiffel-Université Grenoble Alpes (UGA), European Synchroton Radiation Facility [Grenoble] (ESRF), Bundesanstalt für Geowissenschaften und Rohstoffe (BGR), United States Geological Survey (USGS), and Universität Bremen
Subjects: birnessite, Atmospheric Science, EXAFS, Space and Planetary Science, Geochemistry and Petrology, todorokite, [SDU.STU.GC]Sciences of the Universe [physics]/Earth Sciences/Geochemistry, vernadite, Raman spectroscopy, XANES, X-ray diffraction, [SDU.STU.MI]Sciences of the Universe [physics]/Earth Sciences/Mineralogy
Abstract: International audience; Our understanding of the up to seven orders of magnitude partitioning of thallium (Tl) between seawater and ferromanganese (FeMn) deposits rests upon two foundations: (1) being able to quantify the Tl(I)/Tl(III) ratio that reflects the extent of the oxidative scavenging of Tl by vernadite (δ-MnO2), the principle manganate mineral in oxic and suboxic environments, and (2) being able to determine the sorption sites and bonding environments of the Tl(I) and Tl(III) complexes on vernadite. We investigated these foundations by determining the oxidation state and chemical form of Tl in FeMn crusts and nodules from the global oceans at a Tl concentration ranging from several hundreds ppm (mg/kg) down to the low ppm level. Seventeen hydrogenetic crusts and eleven nodules from the Pacific, Atlantic, and Indian oceans and Baltic Sea were characterized by chemical analysis, X-ray diffraction, Raman spectroscopy, Mn K-edge X-ray absorption near-edge structure (XANES) spectroscopy, and Tl L3-edge high energy-resolution XANES (HR-XANES) and extended X-ray absorption fine structure (EXAFS) spectroscopy. The Tl concentration increases linearly from 1.5 to 319 ppm with the Mn/Fe ratio in Fe-vernadite from hydrogenetic crusts, whereas the percentage of Tl(III) to total Tl varies between 62% and 100% independent of both the Mn/Fe and Mn(III)/Mn(IV) 2 ratios. The data, complemented by molecular modeling of the Tl(III) coordination and by XANES calculations, suggest that the enrichment of Tl in Fe-vernadite is driven by (1) the oxidative uptake of octahedrally coordinated Tl(III) above the vacant Mn(IV) sites and on the layer edges of the vernadite layers, and (2) the sorption of Tl(I) on the crystallographic site of Ba at the surface of the vernadite layers, which is analog to the surface site of K. Thus, Tl has a high affinity for vernadite regardless of its oxidation state, and the lack of correlation between Tl(III) and the Mn/Fe ratio in FeMn crusts is explained by the affinity of Tl(I) for the Ba site. The Tl concentration varies between 2 and 112 ppm in surface and buried nodules independent of the Mn/Fe ratio, and the percentage of Tl(III) varies between 0% and 100%. Nodules subjected to sediment diagenesis with replacement of layered vernadite by tunneled todorokite are depleted in Tl and have more reduced thallium. Knowledge of the complex interplay of mineralogy, surface chemical processes, and crystallographic siting are required to understand the variability of Tl concentrations, redox state, and acquisition processes by marine FeMn deposits.
Published: 2022
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4. Origin of manganese in nannofossil calcite based on synchrotron nanoXRF and Xanes

Author: Isabelle Daniel, Alexandre Simionovici, Karl-Heinz Baumann, Fabienne Giraud, Marie-Pierre Aubry, Baptiste Suchéras-Marx, Camille Rivard, Luc Beaufort, Rémi Tucoulou, Centre européen de recherche et d'enseignement des géosciences de l'environnement (CEREGE), Institut de Recherche pour le Développement (IRD)-Aix Marseille Université (AMU)-Collège de France (CdF (institution))-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Institut des Sciences de la Terre (ISTerre), Institut national des sciences de l'Univers (INSU - CNRS)-Institut de recherche pour le développement [IRD] : UR219-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Gustave Eiffel-Université Grenoble Alpes (UGA), Laboratoire de Géologie de Lyon - Terre, Planètes, Environnement (LGL-TPE), École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut national des sciences de l'Univers (INSU - CNRS)-Université Jean Monnet - Saint-Étienne (UJM)-Centre National de la Recherche Scientifique (CNRS), Synchrotron SOLEIL (SSOLEIL), Centre National de la Recherche Scientifique (CNRS), European Synchrotron Radiation Facility (ESRF), Rutgers University System (Rutgers), Fachbereich Geowissenschaften [Bremen], Universität Bremen, Institut national des sciences de l'Univers (INSU - CNRS)-Institut de recherche pour le développement [IRD] : UR219-Université Grenoble Alpes (UGA)-Université Gustave Eiffel-Centre National de la Recherche Scientifique (CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry]), Laboratoire de Géologie de Lyon - Terre, Planètes, Environnement [Lyon] (LGL-TPE), École normale supérieure - Lyon (ENS Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Claude Bernard Lyon 1 (UCBL), and Université de Lyon-Université de Lyon-École normale supérieure - Lyon (ENS Lyon)
Subjects: Calcite, 010504 meteorology & atmospheric sciences, biology, Paleontology, chemistry.chemical_element, Mineralogy, Manganese, 010502 geochemistry & geophysics, Oceanography, biology.organism_classification, 01 natural sciences, Deep sea, Incertae sedis, XANES, Diagenesis, Foraminifera, chemistry.chemical_compound, chemistry, 13. Climate action, [SDU.STU.GC]Sciences of the Universe [physics]/Earth Sciences/Geochemistry, 14. Life underwater, [SDU.STU.PG]Sciences of the Universe [physics]/Earth Sciences/Paleontology, Calcareous, Geology, 0105 earth and related environmental sciences
Abstract: Calcareous nannofossils are micrometric calcite platelets secreted by the photosynthetic algae named coccolithophores and incertae sedis. Calcareous nannoplankton inhabit the photic zone from coast to open-ocean and have left an abundant fossil record since the Triassic. Therefore, they constitute an interesting material for geochemical studies although they have been overlooked in comparison to foraminifera. We have analyzed manganese distribution and valence in six calcareous nannofossil species representing different ages (Recent to Jurassic) and geological settings (land sections and deep ocean core-tops) and with different structures to assess the potential of Mn as a paleobiological or paleoenvironmental proxy. Nano x -Ray Fluorescence ( xrf ) maps were established at the esrf id 22 ni and id 21 beamlines and Mn k -edge x -Ray Absorption Near Edge Structure ( xanes ) at id 21. Mn is more abundant in nannofossils from pre-Quaternary rock samples than from core-top samples. In nannofossil rock samples, Mn nano xrf maps show distributions correlated with primary crystalline organization whereas in nannofossil core-top samples, Mn is either absent or does not follow the crystal organization. X anes analyses show that Mn is in the form of MnCO3. All these observations argue for Mn incorporation within calcareous nannofossils controlled by diagenesis through overgrowth of secondary calcite (Ca, Mn)CO3. Crusts grew along the original crystal growth directions. The incorporation of Mn in some core-top samples highlights potential early diagenesis input when the detached platelet lies on the seafloor or is still in the water column. Mn should therefore be considered a critical tool to identify diagenetic overgrowth rather than primary environmental conditions.
Published: 2021
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5. 20 years of Quarantine Extraterrestrial Sample Analyses methodology

Author: Pierre Beck, Lara Maldanis, Michel Viso, Remi Tucoulou Tachoueres, Kateryna Kiryukhina, Francois Fihman, Tom Schoonjans, Laurence Lemelle, and Alexandre Simionovici
Subjects: law, Extraterrestrial life, Environmental health, Quarantine, Environmental science, Sample (statistics), law.invention
Published: 2021
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6. Oldest methanogens from subseafloor hydrothermal environment, South Africa

Author: Emilie Thomassot, Murielle Salomé, Assimo Maris, Michael J. Russell, Elena Bailo, Alain Manceau, Alexandre Simionovici, Sherry L. Cady, Roberto Canteri, Remi Tucoulou Tachoueres, Barbara Cavalazzi, Emanuele Enrico, Nordine Bouden, Axel Hofmann, and Laurence Lemelle
Subjects: Earth science, Hydrothermal circulation, Geology
Published: 2021
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7. From petrography to nanoscale: new approach for 3D investigations of fossilized microorganisms from Mars analogue deposits

Author: Alexandre Simionovici, Lara Maldanis, Mirko Holler, Laurence Lemelle, David Fernandez-Remolar, and Manuel Guizar-Sicairos
Subjects: Petrography, Mars Exploration Program, Geology, Astrobiology
Published: 2021
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8. Evidence of high Sr/Ca in a Middle Jurassic murolith coccolith species

Author: Isabelle Daniel, Alexandre Simionovici, Rémi Tucoulou, Fabienne Giraud, Baptiste Suchéras-Marx, Centre européen de recherche et d'enseignement des géosciences de l'environnement (CEREGE), Institut de Recherche pour le Développement (IRD)-Aix Marseille Université (AMU)-Collège de France (CdF (institution))-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Institut des Sciences de la Terre (ISTerre), Institut national des sciences de l'Univers (INSU - CNRS)-Institut de recherche pour le développement [IRD] : UR219-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Gustave Eiffel-Université Grenoble Alpes (UGA), Institut Universitaire de France (IUF), Ministère de l'Education nationale, de l’Enseignement supérieur et de la Recherche (M.E.N.E.S.R.), European Synchrotron Radiation Facility (ESRF), Laboratoire de Géologie de Lyon - Terre, Planètes, Environnement (LGL-TPE), École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut national des sciences de l'Univers (INSU - CNRS)-Université Jean Monnet - Saint-Étienne (UJM)-Centre National de la Recherche Scientifique (CNRS), European Synchroton Radiation Facility [Grenoble] (ESRF), Institut national des sciences de l'Univers (INSU - CNRS)-Institut de recherche pour le développement [IRD] : UR219-Université Grenoble Alpes (UGA)-Université Gustave Eiffel-Centre National de la Recherche Scientifique (CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry]), Laboratoire de Géologie de Lyon - Terre, Planètes, Environnement [Lyon] (LGL-TPE), École normale supérieure - Lyon (ENS Lyon)-Université Claude Bernard Lyon 1 (UCBL), and Université de Lyon-Université de Lyon-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Calcite, Elemental composition, Coccoliths, 010504 meteorology & atmospheric sciences, Chemistry, XRF, Geochemistry, Pelagic zone, 010502 geochemistry & geophysics, 01 natural sciences, Diagenesis, Coccolith, chemistry.chemical_compound, Sr/Ca, Muroliths, Ultrastructure, [SDU.STU.GC]Sciences of the Universe [physics]/Earth Sciences/Geochemistry, Calcareous nannofossils, Scyphosphaera apsteinii, Seawater, Photic zone, ESRF, 14. Life underwater, [SDU.STU.PG]Sciences of the Universe [physics]/Earth Sciences/Paleontology, 0105 earth and related environmental sciences
Abstract: Paleoceanographical reconstructions are often based on microfossil geochemical analyses. Coccoliths are the most ancient, abundant and continuous record of pelagic photic zone calcite producer organisms. Hence, they could be valuable substrates for geochemically based paleoenvironmental reconstructions but only Sr/Ca is exploited even if it remains poorly understood. For example, some murolith coccoliths species have very high Sr/Ca compared to the common 1-4 mmol/mol recorded in placolith coccoliths. In this study, we analyzed the elemental composition of the Middle Jurassic murolith Crepidolithus crassus by synchrotron-based nanoXRF (X-ray Fluorescence Spectroscopy) mapping focusing on Sr/Ca and compared the record to two placolith species, namely Watznaueria contracta and Discorhabdus striatus. In C. crassus, Sr/Ca is more than ten times higher than in both placoliths and seems higher in the proximal cycle. By comparison with the placoliths analyzed in the same analytical set-up and from the same sample, we exclude the impact of the diagenesis and seawater Sr/Ca to explain the high Sr/Ca in C. crassus. Based on comparisons to Pontosphaera discopora and Scyphosphaera apsteinii which also have high Sr/Ca, it seems more likely that high Sr/Ca in C. crassus is either due to the vertical elongation of the R-units of the proximal cycle or related to the action of the special polysaccharide controlling the growth of those vertically elongated R-units that may have affinities to Sr2+ . In order to apply the Sr/Ca proxy to muroliths, further investigations are needed on cultured coccoliths.
Published: 2020
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9. The Mode of Incorporation of As(-I) and Se(-I) in Natural Pyrite Revisited

Author: Stephan N. Steinmann, Magdalena Murdzek, Dogan Paktunc, Valentina Batanova, Alain Manceau, Olivier Mathon, Pieter Glatzel, Margarita Merkulova, Alexandre Simionovici, Institut des Sciences de la Terre (ISTerre), Institut national des sciences de l'Univers (INSU - CNRS)-Institut de recherche pour le développement [IRD] : UR219-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Gustave Eiffel-Université Grenoble Alpes (UGA), European Synchrotron Radiation Facility (ESRF), Laboratoire de Chimie - UMR5182 (LC), École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), CanMet, Environment and Climate Change Canada, Laboratoire de Géophysique Interne et Tectonophysique (LGIT), Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Laboratoire Central des Ponts et Chaussées (LCPC)-Institut des Sciences de la Terre (ISTerre), Université Grenoble Alpes (UGA)-Centre National de la Recherche Scientifique (CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-PRES Université de Grenoble-Institut de recherche pour le développement [IRD] : UR219-Institut national des sciences de l'Univers (INSU - CNRS)-Institut Français des Sciences et Technologies des Transports, de l'Aménagement et des Réseaux (IFSTTAR)-Université Joseph Fourier - Grenoble 1 (UJF)-Centre National de la Recherche Scientifique (CNRS)-PRES Université de Grenoble-Institut de recherche pour le développement [IRD] : UR219-Institut Français des Sciences et Technologies des Transports, de l'Aménagement et des Réseaux (IFSTTAR), Université Grenoble Alpes (UGA)-Centre National de la Recherche Scientifique (CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-PRES Université de Grenoble-Institut de recherche pour le développement [IRD] : UR219-Institut national des sciences de l'Univers (INSU - CNRS)-Institut Français des Sciences et Technologies des Transports, de l'Aménagement et des Réseaux (IFSTTAR)-Université Joseph Fourier - Grenoble 1 (UJF), Laboratoire de Géodynamique des Chaines Alpines (LGCA), Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Institut des Sciences de la Terre (ISTerre), École normale supérieure - Lyon (ENS Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-École normale supérieure - Lyon (ENS Lyon)-Institut de Chimie du CNRS (INC), Institut national des sciences de l'Univers (INSU - CNRS)-Institut de recherche pour le développement [IRD] : UR219-Université Grenoble Alpes [2020-....] (UGA [2020-....])-Université Gustave Eiffel (UNIV GUSTAVE EIFFEL)-Centre National de la Recherche Scientifique (CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry]), Natural Resources Canada (NRCan), Institut des Sciences de la Terre [2020-….] (ISTerre [2020-….]), and Institut national des sciences de l'Univers (INSU - CNRS)-Institut de recherche pour le développement [IRD] : UR219-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Gustave Eiffel (UNIV GUSTAVE EIFFEL)-Université Grenoble Alpes [2020-....] (UGA [2020-....])
Subjects: inorganic chemicals, Atmospheric Science, chemistry.chemical_element, 010501 environmental sciences, engineering.material, 010502 geochemistry & geophysics, 01 natural sciences, DFT, Natural (archaeology), Hydrothermal circulation, Crystal14, Geochemistry and Petrology, [CHIM]Chemical Sciences, Coal, selenium, [SDU.ENVI]Sciences of the Universe [physics]/Continental interfaces, environment, Arsenic, 0105 earth and related environmental sciences, Chemistry, business.industry, ab initio, arsenic, [CHIM.CATA]Chemical Sciences/Catalysis, XANES, [CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistry, EXAFS, 13. Climate action, Space and Planetary Science, Environmental chemistry, engineering, Sedimentary rock, Pyrite, business, Selenium
Abstract: International audience; Pyrite (FeS2) from coal, sedimentary rocks, and hydrothermal ore deposits generally contains hazardous selenium (Se) and arsenic (As) that are released in natural waters through oxidative dissolution of the host. Knowing how As and Se are structurally incorporated into pyrite has important implication in controlling or preventing their release because trace metal(loid) substitution accelerates the dissolution of pyrite. Previous extended X-ray absorption fine structure (EXAFS) studies have reported that nominally monovalent arsenic clusters at the sulfur site forming As-As pairs at 3.2 Å, whereas monovalent Se does not form Se-Se pairs at this distance for unknown reason. Here, we revisit this question using As and Se K-edge X-ray absorption near-edge structure (XANES) and EXAFS spectroscopy complemented with atomistic calculations. We find that neither As nor Se atoms can be differentiated from S atom at 3.2-3.3 Å, the cluster and dilute model-fits to As-and Se-EXAFS data yielding equivalent least-squares solutions. Thermodynamic calculations of Fe48As3S93 (3.8 wt.% As) and Fe48Se3S93 (4.0 wt.% Se) structures show that the formation of As-As pairs is energetically favorable and the formation of Se-Se pairs unfavorable. Thus, the equilibrium distribution of As and Se predicted by calculation agrees with published EXAFS data. However, this agreement is incidental because EXAFS fits are ambiguous, the same EXAFS spectra being fit indifferently with a cluster and 2 a dilute model. Regarding Se, the dilute model-fit is probably correct since Se-Se pairs are precluded thermodynamically. The situation is less clear for As. The lowest energy atomic arrangement of As in Fe48S93As3 is similar to the local structure of As in arsenopyrite (FeAsS), thus supporting the cluster model. However, the energy gain to total energy provided by the formation of As clusters decreases with decreasing As concentration, making them thermodynamically less favorable below 1.0 wt.%. Determining the actual distribution pattern of As in pyrite is challenging.
Published: 2020
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10. Nano-imaging trace elements at organelle levels in substantia nigra overexpressing α-synuclein to model Parkinson's disease

Author: Graham Knott, Philippe Colin, Peter Cloetens, Alexandre Simionovici, Bernard L. Schneider, Laurence Lemelle, Sylvain Bohic, Laboratoire de Sciences de la Terre (LST), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-École normale supérieure - Lyon (ENS Lyon), Institut des Sciences de la Terre (ISTerre), Institut national des sciences de l'Univers (INSU - CNRS)-Institut de recherche pour le développement [IRD] : UR219-Université Grenoble Alpes (UGA)-Université Gustave Eiffel-Centre National de la Recherche Scientifique (CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry]), Ecole Polytechnique Fédérale de Lausanne (EPFL), European Synchrotron Radiation Facility (ESRF), Brain and Mind Institute [Lausanne, Switzerland], École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), and Institut national des sciences de l'Univers (INSU - CNRS)-Institut de recherche pour le développement [IRD] : UR219-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Gustave Eiffel-Université Grenoble Alpes (UGA)
Subjects: 0301 basic medicine, Nucleolus, [SDV.IB.IMA]Life Sciences [q-bio]/Bioengineering/Imaging, Iron, Medicine (miscellaneous), Substantia nigra, [SDV.BC.BC]Life Sciences [q-bio]/Cellular Biology/Subcellular Processes [q-bio.SC], General Biochemistry, Genetics and Molecular Biology, Article, Lipofuscin, Rats, Sprague-Dawley, 03 medical and health sciences, 0302 clinical medicine, Microscopy, Electron, Transmission, Organelle, Image Processing, Computer-Assisted, Animals, lcsh:QH301-705.5, Cellular compartment, Organelles, Chemistry, Endoplasmic reticulum, Dopaminergic Neurons, Spectrometry, X-Ray Emission, Parkinson Disease, Nuclear matrix, Cellular neuroscience, 3. Good health, Rats, Trace Elements, Substantia Nigra, 030104 developmental biology, lcsh:Biology (General), Cytoplasm, Biophysics, alpha-Synuclein, [SDV.NEU]Life Sciences [q-bio]/Neurons and Cognition [q-bio.NC], Female, General Agricultural and Biological Sciences, [SPI.SIGNAL]Engineering Sciences [physics]/Signal and Image processing, 030217 neurology & neurosurgery, Synchrotrons
Abstract: Sub-cellular trace element quantifications of nano-heterogeneities in brain tissues offer unprecedented ways to explore at elemental level the interplay between cellular compartments in neurodegenerative pathologies. We designed a quasi-correlative method for analytical nanoimaging of the substantia nigra, based on transmission electron microscopy and synchrotron X-ray fluorescence. It combines ultrastructural identifications of cellular compartments and trace element nanoimaging near detection limits, for increased signal-to-noise ratios. Elemental composition of different organelles is compared to cytoplasmic and nuclear compartments in dopaminergic neurons of rat substantia nigra. They exhibit 150–460 ppm of Fe, with P/Zn/Fe-rich nucleoli in a P/S-depleted nuclear matrix and Ca-rich rough endoplasmic reticula. Cytoplasm analysis displays sub-micron Fe/S-rich granules, including lipofuscin. Following AAV-mediated overexpression of α-synuclein protein associated with Parkinson’s disease, these granules shift towards higher Fe concentrations. This effect advocates for metal (Fe) dyshomeostasis in discrete cytoplasmic regions, illustrating the use of this method to explore neuronal dysfunction in brain diseases., Lemelle et al. describe the use of TEM and synchrotron X-ray fluorescence for quasi-correlative nanoimaging and sub-cellular trace element quantification of rat brain tissue. They further observe elemental (iron and sulfur) dyshomeostasis in cytoplasmic granules when overexpressing α-synuclein protein associated with Parkinson’s disease, demonstrating the usefulness of this method to further explore dysfunctions at organelle levels in brain diseases.
Published: 2019
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11. High‐resolution wavelength‐dispersive spectroscopy of K‐shell transitions in hydrogen‐like gold

Author: Csilla I. Szabo, Wanqiu Chen, N. Petridis, S. Hagmann, R. Heß, K. S. Schulze, G. Weber, C. Dimopoulou, U. Spillmann, F. Nolden, Michael Lestinsky, S. Trotsenko, O. Wehrhan, D. Liesen, Ingo Uschmann, N. Winters, Renate Märtin, M. Schwemlein, T. Kämpfer, Alexandre Simionovici, K.-H. Blumenhagen, P. M. Hillenbrand, E. Ziegler, T. Gassner, Martino Trassinelli, C. Brandau, Dariusz Banaś, M. Steck, A. Gumberidze, Paul Indelicato, R. Loetzsch, M. S. Sanjari, Yu. A. Litvinov, Nicolas Winckler, F. Bosch, H. F. Beyer, Th. Stöhlker, Eckhart Förster, Danyal Winters, Robert E. Grisenti, B. Manil, Paweł P. Jagodziński, Helmholtz zentrum für Schwerionenforschung GmbH (GSI), Institut des Nanosciences de Paris (INSP), Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS), Agrégats et surfaces sous excitations intenses (INSP-E10), Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Ottawa Research & Development Centre, Science & Technology Branch, Agriculture and Agri-Food [Ottawa] (AAFC), Laboratoire Kastler Brossel (LKB (Jussieu)), Université Pierre et Marie Curie - Paris 6 (UPMC)-Fédération de recherche du Département de physique de l'Ecole Normale Supérieure - ENS Paris (FRDPENS), Centre National de la Recherche Scientifique (CNRS)-École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS), Institute of Physics [Kielce], Jan Kochanowski University, Laboratoire de Physique des Lasers (LPL), Université Paris 13 (UP13)-Centre National de la Recherche Scientifique (CNRS), Institut für Kernphysik, Goethe-Universität Frankfurt am Main, Laboratoire de Sciences de la Terre (LST), École normale supérieure - Lyon (ENS Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Université Paris 06, X-ray Optics Croup Institute of Optics and Quantum Electronics, Friedrich-Schiller-Universität = Friedrich Schiller University Jena [Jena, Germany], Agriculture and Agri-Food (AAFC), Fédération de recherche du Département de physique de l'Ecole Normale Supérieure - ENS Paris (FRDPENS), École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS), and École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL)
Subjects: Materials science, Hydrogen, [PHYS.PHYS.PHYS-ATOM-PH]Physics [physics]/Physics [physics]/Atomic Physics [physics.atom-ph], Analytical chemistry, Electron shell, chemistry.chemical_element, High resolution, 01 natural sciences, 010305 fluids & plasmas, Wavelength-dispersive X-ray spectroscopy, chemistry, 0103 physical sciences, 010306 general physics, Spectroscopy, ComputingMilieux_MISCELLANEOUS
Abstract: International audience
Published: 2019
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12. X‐Rays Analysis for Space Sciences: X‐Ray Fluorescence Spectroscopy

Author: Alexandre Simionovici, Laurence Lemelle, Institut des Sciences de la Terre (ISTerre), Institut Français des Sciences et Technologies des Transports, de l'Aménagement et des Réseaux (IFSTTAR)-Institut national des sciences de l'Univers (INSU - CNRS)-Institut de recherche pour le développement [IRD] : UR219-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), Laboratoire de Géologie de Lyon - Terre, Planètes, Environnement [Lyon] (LGL-TPE), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-École normale supérieure - Lyon (ENS Lyon), Laboratoire de Géologie de Lyon - Terre, Planètes, Environnement (LGL-TPE), École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), and Université de Lyon-Université de Lyon-Institut national des sciences de l'Univers (INSU - CNRS)-Université Jean Monnet - Saint-Étienne (UJM)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Materials science, biology, Presolar grains, Analytical chemistry, chemistry.chemical_element, Venus, Mars Exploration Program, 010502 geochemistry & geophysics, biology.organism_classification, 01 natural sciences, X-Ray Fluorescence Spectroscopy, Mercury (element), Meteorite, chemistry, [CHIM.ANAL]Chemical Sciences/Analytical chemistry, In situ analysis, 0103 physical sciences, Space Science, 010303 astronomy & astrophysics, 0105 earth and related environmental sciences
Abstract: International audience; X-ray analysis was introduced at the beginning of the twentieth century, right after the discovery of X-rays. It represents a specific group of methods of investigation of samples that share the same probe, the X-rays, and produces nondestructive, highly varied results of the intrinsic properties of specimens. X-ray fluorescence (XRF) is the main method of X-ray analysis and, as such, constitutes the subject of this article, where it is applied to the priceless astromaterials, better known as extraterrestrial samples. These comprise recorded falls (meteorites), samples collected in space, and sample return mission (SRM) specimens brought back to Earth by space missions, or simply by in situ measurements on Solar System bodies, or from remote orbital or flyby analyses thereof.
Published: 2018
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13. Origin of EL3 chondrites: Evidence for variable C/O ratios during their course of formation-A state of the art scrutiny

Author: Masaaki Miyahara, Eiji Ohtani, A. El Goresy, Alexandre Simionovici, Yangting Lin, L. Feng, Abdelmouhcine Gannoun, Maud Boyet, Mario Trieloff, Ph. Gillet, Laurence Lemelle, Bavarian Research Institute of Experimental Geochemistry and Geophysics (Bayerisches Geoinstitut), Universität Bayreuth, Key Laboratory of Earth and Planetary Physics, Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing, 100029, China., Department of Earth and Planetary Systems Science, Graduate School of Science, Hiroshima University, Laboratoire Magmas et Volcans (LMV), Institut national des sciences de l'Univers (INSU - CNRS)-Université Jean Monnet - Saint-Étienne (UJM)-Institut de Recherche pour le Développement et la société-Université Clermont Auvergne [2017-2020] (UCA [2017-2020])-Centre National de la Recherche Scientifique (CNRS)-Observatoire de Physique du Globe de Clermont-Ferrand (OPGC), Institut national des sciences de l'Univers (INSU - CNRS)-Université Clermont Auvergne [2017-2020] (UCA [2017-2020])-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Clermont Auvergne [2017-2020] (UCA [2017-2020])-Centre National de la Recherche Scientifique (CNRS), Department of Earth Sciences, Graduate School of Science, Tohoku University, Ecole Polytechnique Fédérale de Lausanne (EPFL), Universität Heidelberg [Heidelberg] = Heidelberg University, Institut des Sciences de la Terre (ISTerre), Institut Français des Sciences et Technologies des Transports, de l'Aménagement et des Réseaux (IFSTTAR)-Institut national des sciences de l'Univers (INSU - CNRS)-Institut de recherche pour le développement [IRD] : UR219-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), Laboratoire de Géologie de Lyon - Terre, Planètes, Environnement (LGL-TPE), École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut national des sciences de l'Univers (INSU - CNRS)-Université Jean Monnet - Saint-Étienne (UJM)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Catalyse et Synthèse Organique (LCSO), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon, Institut national des sciences de l'Univers (INSU - CNRS)-Université Jean Monnet [Saint-Étienne] (UJM)-Université Blaise Pascal - Clermont-Ferrand 2 (UBP)-Observatoire de Physique du Globe de Clermont-Ferrand (OPGC), Université Blaise Pascal - Clermont-Ferrand 2 (UBP)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), Conseil Elevage, Universität Heidelberg [Heidelberg], Laboratoire de Sciences de la Terre (LST), École normale supérieure - Lyon (ENS Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Géomatériaux et Environnement (LGE), Université Paris-Est Marne-la-Vallée (UPEM), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Blaise Pascal - Clermont-Ferrand 2 (UBP)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), Bavarian Research Institute of Experimental Geochemistry and Geophysics ( Bayerisches Geoinstitut ), Universität Bayreuth-University of Bayreuth, Laboratoire de Catalyse et Synthèse Organique ( LCSO ), Université Claude Bernard Lyon 1 ( UCBL ), Laboratoire Magmas et Volcans ( LMV ), Université Blaise Pascal - Clermont-Ferrand 2 ( UBP ) -Institut national des sciences de l'Univers ( INSU - CNRS ) -Université Jean Monnet [Saint-Étienne] ( UJM ) -Centre National de la Recherche Scientifique ( CNRS ), Laboratoire de Sciences de la Terre ( LST ), École normale supérieure - Lyon ( ENS Lyon ) -Université Claude Bernard Lyon 1 ( UCBL ), Université de Lyon-Université de Lyon-Institut national des sciences de l'Univers ( INSU - CNRS ) -Centre National de la Recherche Scientifique ( CNRS ), Laboratoire Géomatériaux et Environnement ( LGE ), Université Paris-Est Marne-la-Vallée ( UPEM ), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Claude Bernard Lyon 1 (UCBL), and Université de Lyon-Université de Lyon-École normale supérieure - Lyon (ENS Lyon)
Subjects: chemistry.chemical_classification, Mineral, 010504 meteorology & atmospheric sciences, Sulfide, Geochemistry, Mineralogy, Chondrule, engineering.material, [ SDU.STU.GC ] Sciences of the Universe [physics]/Earth Sciences/Geochemistry, 010502 geochemistry & geophysics, 01 natural sciences, Geophysics, chemistry, Meteorite, 13. Climate action, Space and Planetary Science, Chondrite, [SDU.STU.GC]Sciences of the Universe [physics]/Earth Sciences/Geochemistry, Oldhamite, Enstatite, engineering, Lithophile, Geology, ComputingMilieux_MISCELLANEOUS, 0105 earth and related environmental sciences
Abstract: International audience; Mineral inventories of enstatite chondrites; (EH and EL) are strictly dictated by combined parameters mainly very low dual oxygen (fO2) and sulfur (fS2) fugacities. They are best preserved in the Almahata Sitta MS-17, MS-177 fragments, and the ALHA 77295 and MAC 88136 Antarctic meteorites. These conditions induce a stark change of the geochemical behavior of nominally lithophile elements to chalcophile or even siderophile and changes in the elemental partitioning thus leading to formation of unusual mineral assemblages with high abundance of exotic sulfide species and enrichment in the metallic alloys, for example, silicides and phosphides. Origin and mode of formation of these exotic chondrites, and their parental source regions could be best scrutinized by multitask research experiments of the most primitive members covering mineralogical, petrological, cosmochemical, and indispensably short-lived isotopic chronology. The magnitude of temperature and pressure prevailed during their formation in their source regions could eventually be reasonably estimated: pre- and postaccretionary could eventually be deduced. The dual low fugacities are regulated by the carbon to oxygen ratios estimated to be >0.83 and
Published: 2017
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14. Stardust Interstellar Preliminary Examination V: XRF analyses of interstellar dust candidates at ESRF ID13

Author: P. Fougeray, Anna L. Butterworth, Mark C. Price, Rhonda M. Stroud, Wei Ja Ong, Eberhard Grün, Anton T. Kearsley, D. Frank, Bart Vekemans, Hitesh Changela, Ron K. Bastien, George J. Flynn, Thomas Stephan, Tolek Tyliszczak, Vicente A. Solé, Ralf Srama, Joshua Von Korff, Peter Hoppe, Laszlo Vincze, R. Lettieri, Andrew M. Davis, Zack Gainsforth, Frank Postberg, Akira Tsuchiyama, Hugues Leroux, Ashley J. King, Sylvia Schmitz, Julien Stodolna, Saša Bajt, Carlton Allen, Steven Sutton, Brit Hvide, Janet Borg, Joachim Huth, Hans A. Bechtel, Geert Silversmit, Larry R. Nittler, Ryan Doll, Peter Tsou, Donald E. Brownlee, Michael E. Zolensky, William Marchant, Tom Schoonjans, Frank E. Brenker, Frank J. Stadermann, Laurence Lemelle, Daniel Zevin, Juan-Angel Sans Tresseras, Naomi Wordsworth, Ariel Leonard, Philipp R. Heck, Nabil Bassim, Scott A. Sandford, Veerle Sterken, Jon K. Hillier, John Bridges, Mark J. Burchell, Bruce Hudson, Ryan C. Ogliore, Jan Leitner, Mario Trieloff, Asna Ansari, David Anderson, Barry Lai, Manfred Burghammer, Andrew J. Westphal, Alexandre Simionovici, Peter Cloetens, Christine Floss, Laboratoire de Géologie de Lyon - Terre, Planètes, Environnement [Lyon] (LGL-TPE), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-École normale supérieure - Lyon (ENS Lyon), Laboratoire de Géologie de Lyon - Terre, Planètes, Environnement (LGL-TPE), École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), and Université de Lyon-Université de Lyon-Institut national des sciences de l'Univers (INSU - CNRS)-Université Jean Monnet - Saint-Étienne (UJM)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Physics, Astronomy, Extraterrestrial materials, X-ray fluorescence, Astrophysics, 010502 geochemistry & geophysics, 01 natural sciences, Synchrotron, law.invention, Interstellar medium, Geophysics, Interplanetary dust cloud, [SDU]Sciences of the Universe [physics], 13. Climate action, Space and Planetary Science, law, 0103 physical sciences, Particle, Ejecta, 010303 astronomy & astrophysics, 0105 earth and related environmental sciences, Cosmic dust
Abstract: Here, we report analyses by synchrotron X-ray fluorescence microscopy of the elemental composition of eight candidate impact features extracted from the Stardust Interstellar Dust Collector (SIDC). Six of the features were unambiguous tracks, and two were crater-like features. Five of the tracks are so-called “midnight” tracks—that is, they had trajectories consistent with an origin either in the interstellar dust stream or as secondaries from impacts on the Sample Return Capsule (SRC). In a companion paper reporting synchrotron X-ray diffraction analyses of ISPE candidates, we show that two of these particles contain natural crystalline materials: the terminal particle of track 30 contains olivine and spinel, and the terminal particle of track 34 contains olivine. Here, we show that the terminal particle of track 30, Orion, shows elemental abundances, normalized to Fe, that are close to CI values, and a complex, fine-grained structure. The terminal particle of track 34, Hylabrook, shows abundances that deviate strongly from CI, but shows little fine structure and is nearly homogenous. The terminal particles of other midnight tracks, 29 and 37, had heavy element abundances below detection threshold. A third, track 28, showed a composition inconsistent with an extraterrestrial origin, but also inconsistent with known spacecraft materials. A sixth track, with a trajectory consistent with secondary ejecta from an impact on one of the spacecraft solar panels, contains abundant Ce and Zn. This is consistent with the known composition of the glass covering the solar panel. Neither crater-like feature is likely to be associated with extraterrestrial materials. We also analyzed blank aerogel samples to characterize background and variability between aerogel tiles. We found significant differences in contamination levels and compositions, emphasizing the need for local background subtraction for accurate quantification.
Published: 2014
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15. Final reports of the Stardust Interstellar Preliminary Examination

Author: Rhonda M. Stroud, George J. Flynn, Hitesh Changela, Thomas Stephan, Zack Gainsforth, Anna L. Butterworth, Ron K. Bastien, Peter Cloetens, Vicente A. Solé, Janet Borg, Tolek Tyliszczak, Peter Hoppe, Hans A. Bechtel, Laszlo Vincze, Nabil Bassim, Larry R. Nittler, Julien Stodolna, Naomi Wordsworth, Ryan Doll, Peter Tsou, Mario Trieloff, Steven Sutton, Joshua Von Korff, Christine Floss, Michael E. Zolensky, Sylvia Schmitz, Brit Hvide, Akira Tsuchiyama, Carlton Allen, Frank Postberg, Jan Leitner, Anton T. Kearsley, D. Frank, David Anderson, John Bridges, Barry Lai, Tom Schoonjans, Ashley J. King, Laurence Lemelle, Manfred Burghammer, Eberhard Grün, Saša Bajt, Andrew J. Westphal, Veerle Sterken, Bart Vekemans, Joachim Huth, Philipp R. Heck, Geert Silversmit, Ralf Srama, Mark C. Price, Ariel Leonard, Alexandre Simionovici, Mark J. Burchell, R. Lettieri, Asna Ansari, Wei Ja Ong, Frank E. Brenker, Frank J. Stadermann, William Marchant, Juan-Angel Sans Tresseras, Andrew M. Davis, Donald E. Brownlee, Scott A. Sandford, Hugues Leroux, Daniel Zevin, Jon K. Hillier, Bruce Hudson, Ryan C. Ogliore, Laboratoire de Géologie de Lyon - Terre, Planètes, Environnement [Lyon] (LGL-TPE), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-École normale supérieure - Lyon (ENS Lyon), Laboratoire de Géologie de Lyon - Terre, Planètes, Environnement (LGL-TPE), École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), and Université de Lyon-Université de Lyon-Institut national des sciences de l'Univers (INSU - CNRS)-Université Jean Monnet - Saint-Étienne (UJM)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Physics, Mass distribution, Astronomy, Extraterrestrial materials, 010502 geochemistry & geophysics, 01 natural sciences, Astrobiology, Geophysics, Meteorite, Impact crater, [SDU]Sciences of the Universe [physics], 13. Climate action, Space and Planetary Science, Extraterrestrial life, 0103 physical sciences, Sample collection, Interplanetary spaceflight, 010303 astronomy & astrophysics, 0105 earth and related environmental sciences, Cosmic dust
Abstract: With the discovery of bona fide extraterrestrial materials in the Stardust Interstellar Dust Collector, NASA now has a fundamentally new returned sample collection, after the Apollo, Antarctic meteorite, Cosmic Dust, Genesis, Stardust Cometary, Hayabusa, and Exposed Space Hardware samples. Here, and in companion papers in this volume, we present the results from the Preliminary Examination of this collection, the Stardust Interstellar Preliminary Examination (ISPE). We found extraterrestrial materials in two tracks in aerogel whose trajectories and morphology are consistent with an origin in the interstellar dust stream, and in residues in four impacts in the aluminum foil collectors. While the preponderance of evidence, described in detail in companion papers in this volume, points toward an interstellar origin for some of these particles, alternative origins have not yet been eliminated, and definitive tests through isotopic analyses were not allowed under the terms of the ISPE. In this summary, we answer the central questions of the ISPE: How many tracks in the collector are consistent in their morphology and trajectory with interstellar particles? How many of these potential tracks are consistent with real interstellar particles, based on chemical analysis? Conversely, what fraction of candidates are consistent with either a secondary or interplanetary origin? What is the mass distribution of these particles, and what is their state? Are they particulate or diffuse? Is there any crystalline material? How many detectable impact craters (> 100 nm) are there in the foils, and what is their size distribution? How many of these craters have analyzable residue that is consistent with extraterrestrial material? And finally, can craters from secondaries be recognized through crater morphology (e.g., ellipticity)?
Published: 2014
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16. Stardust Interstellar Preliminary Examination XI: Identification and elemental analysis of impact craters on Al foils from the Stardust Interstellar Dust Collector

Author: Brit Hvide, Veerle Sterken, Akira Tsuchiyama, Larry R. Nittler, Carlton Allen, Mark C. Price, Zack Gainsforth, Mark J. Burchell, Laurence Lemelle, Kate Schreiber, Jan Leitner, Philipp R. Heck, Nabil Bassim, Asna Ansari, Michael E. Zolensky, Rhonda M. Stroud, Paul G. Kotula, Andrew M. Davis, Scott A. Sandford, Anna L. Butterworth, Thomas Stephan, Frank Postberg, Mario Trieloff, Eberhard Grün, Christine Floss, Vicente A. Solé, Hugues Leroux, Ryan Doll, Barry Lai, Donald E. Brownlee, Janet Borg, Joshua Von Korff, Hitesh Changela, Peter Tsou, Saša Bajt, Andrew J. Westphal, John Bridges, Anton T. Kearsley, Bart Vekemans, Ralf Srama, D. Frank, Sylvia Schmitz, R. Bastien, Alexandre Simionovici, R. Lettieri, Hans A. Bechtel, Laszlo Vincze, Frank E. Brenker, Tom Schoonjans, David Anderson, Joachim Huth, Steven Sutton, Peter Hoppe, Wei Jia Ong, Ashley J. King, Manfred Burghammer, Julien Stodolna, Ariel Leonard, George J. Flynn, Peter Cloetens, Geert Silversmit, William Marchant, Juan-Angel Sans Tresseras, Tolek Tyliszczak, Daniel Zevin, Ryan C. Ogliore, Jon K. Hillier, Naval Research Laboratory (NRL), NASA Johnson Space Center (JSC), NASA, Field Museum of Natural History [Chicago, USA], University of California [Berkeley] (UC Berkeley), University of California (UC), Deutsches Elektronen-Synchrotron [Hamburg] (DESY), Goethe-University Frankfurt am Main, Lawrence Berkeley National Laboratory [Berkeley] (LBNL), Goethe-Universität Frankfurt am Main, University of Leicester, University of Mary Washington, University of Kent [Canterbury], European Synchrotron Radiation Facility (ESRF), The George Washington University (GW), University of Illinois [Chicago] (UIC), University of Illinois System, Washington University in Saint Louis (WUSTL), State University of New York at Plattsburgh (SUNY Plattsburgh), State University of New York (SUNY), Max-Planck-Institut für Kernphysik (MPIK), Max-Planck-Gesellschaft, University of Heidelberg, Medical Faculty, Max-Planck-Institut für Chemie (MPIC), The Natural History Museum [London] (NHM), Sandia National Laboratory, Argonne National Laboratory [Lemont] (ANL), Laboratoire de Géologie de Lyon - Terre, Planètes, Environnement (LGL-TPE), École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut national des sciences de l'Univers (INSU - CNRS)-Université Jean Monnet - Saint-Étienne (UJM)-Centre National de la Recherche Scientifique (CNRS), Unité Matériaux et Transformations - UMR 8207 (UMET), Institut National de la Recherche Agronomique (INRA)-Ecole Nationale Supérieure de Chimie de Lille (ENSCL)-Institut de Chimie du CNRS (INC)-Université de Lille-Centre National de la Recherche Scientifique (CNRS), Carnegie Institution for Science, University of Hawai‘i [Mānoa] (UHM), NASA Ames Research Center (ARC), Universiteit Gent = Ghent University (UGENT), Observatoire des Sciences de l'Univers de Grenoble (OSUG ), Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), Institut für Biochemie, Biotechnologie und Bioinformatik [TU, Braunschweig], Technische Universität Braunschweig = Technical University of Braunschweig [Braunschweig], University of Stuttgart, Jet Propulsion Laboratory (JPL), NASA-California Institute of Technology (CALTECH), Osaka University [Osaka], National Aeronautics & Space Administration (NASA)NNH11AQ61INNX09AC36G, Laboratoire de Géologie de Lyon - Terre, Planètes, Environnement [Lyon] (LGL-TPE), École normale supérieure - Lyon (ENS Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), and Institut de Chimie du CNRS (INC)-Institut National de la Recherche Agronomique (INRA)-Centre National de la Recherche Scientifique (CNRS)-Université de Lille-Ecole Nationale Supérieure de Chimie de Lille (ENSCL)
Subjects: Scanning electron microscope, FEATURES, COMET 81P/WILD 2, 010502 geochemistry & geophysics, 01 natural sciences, Astrobiology, Interplanetary dust cloud, Impact crater, 0103 physical sciences, Scanning transmission electron microscopy, ISOTOPIC COMPOSITIONS, 010303 astronomy & astrophysics, MISSION, 0105 earth and related environmental sciences, Cosmic dust, Auger electron spectroscopy, TRANSMISSION ELECTRON-MICROSCOPY, ALUMINUM FOILS, AEROGEL, Geophysics, [SDU]Sciences of the Universe [physics], 13. Climate action, Space and Planetary Science, Elemental analysis, RESIDUES, Hypervelocity, MORPHOLOGY, MATTER
Abstract: International audience; The Stardust Interstellar Preliminary Examination team analyzed thirteen Al foils from the NASA Stardust interstellar collector tray in order to locate candidate interstellar dust (ISD) grain impacts. Scanning electron microscope (SEM) images reveal that the foils possess abundant impact crater and crater-like features. Elemental analyses of the crater features, with Auger electron spectroscopy, SEM-based energy dispersive X-ray (EDX) spectroscopy, and scanning transmission electron microscope-based EDX spectroscopy, demonstrate that the majority are either the result of impacting debris fragments from the spacecraft solar panels, or intrinsic defects in the foil. The elemental analyses also reveal that four craters contain residues of a definite extraterrestrial origin, either as interplanetary dust particles or ISD particles. These four craters are designated level 2 interstellar candidates, based on the crater shapes indicative of hypervelocity impacts and the residue compositions inconsistent with spacecraft debris.
Published: 2013
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17. Analytical requirements for quantitative X-ray fluorescence nano-imaging of metal traces in solid samples

Author: Alexandre Simionovici, Rémi Tucoulou, Tom Schoonjans, Axel Hofmann, Laurence Lemelle, Murielle Salomé, Barbara Cavalazzi, Emanuele Enrico, Laboratoire de Géologie de Lyon - Terre, Planètes, Environnement (LGL-TPE), École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut national des sciences de l'Univers (INSU - CNRS)-Université Jean Monnet - Saint-Étienne (UJM)-Centre National de la Recherche Scientifique (CNRS), Lemelle, L., Simionovici, A., Schoonjans, T., Tucoulou, R., Enrico, E., Salomé, M., Hofmann, A., Cavalazzi, B., Laboratoire de Géologie de Lyon - Terre, Planètes, Environnement [Lyon] (LGL-TPE), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Claude Bernard Lyon 1 (UCBL), and Université de Lyon-Université de Lyon-École normale supérieure - Lyon (ENS Lyon)
Subjects: Hard X-ray nanoprobe, Materials science, Monte Carlo method, Analytical chemistry, X-ray fluorescence, Nano-imaging, Nanotechnology, 02 engineering and technology, 01 natural sciences, Analytical Chemistry, Micrometre, FIB, Nano, metal traces, nano-imaging, Synchrotron XRF, hard X-ray Nanoprobe, FIB, X-ray Monte Carlo modeling, Archaean fossils, Barberton, Sample preparation, Spectroscopy, Barberton, Detection limit, X-ray Monte Carlo modeling, 010401 analytical chemistry, 021001 nanoscience & nanotechnology, Metal traces, Synchrotron XRF, Third generation, 0104 chemical sciences, [SDU]Sciences of the Universe [physics], Archaean fossils, Trace analysis, 0210 nano-technology
Abstract: Quantitative nano-imaging of metal traces in a solid is a recent capability arising from the construction of hard X-ray nanoprobes dedicated to X-ray Fluorescence (XRF) imaging on upgraded third generation synchrotrons. Micrometer sample preparation valid for trace analysis is a fundamental part of the required developments to capitalize on the reduced Minimum Detection Limits. Practical guidelines lead us to propose a customized use of Focused Ion Beams (FIB) backed by state of the art Monte Carlo XRF modeling to initiate preparations of new samples and certified standards. The usefulness of these developments is illustrated by the first detection of Ni traces (4.57E+07 ± 3.2E+06 (7.1%) at μm −3 ) in a 3.35 Ga old microstructure of putative microbial origin from Barberton (South Africa). A list of feasibility checks provides a way of getting below 5 ppm MDLs for acquisition-times of 10 s with an analytical precision better than 10%.
Published: 2017
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18. X-Ray-induced Deuterium Enrichment of N-rich Organics in Protoplanetary Disks: An Experimental Investigation Using Synchrotron Light

Author: Mathieu Roskosz, Christophe Sandt, J. L. Lemaire, Alexandre Simionovici, Nicolas Jaouen, Lisseth Gavilan, Laurent Remusat, Nathalie Carrasco, Cornelia Jäger, Thomas Henning, Horia Popescu, Denis Mangin, PLANETO - LATMOS, Laboratoire Atmosphères, Milieux, Observations Spatiales (LATMOS), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Institut de minéralogie, de physique des matériaux et de cosmochimie (IMPMC), Muséum national d'Histoire naturelle (MNHN)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut de recherche pour le développement [IRD] : UR206-Centre National de la Recherche Scientifique (CNRS), Synchrotron SOLEIL (SSOLEIL), Centre National de la Recherche Scientifique (CNRS), Laboratory Astrophysics and Cluster Physics Group, Max-Planck-Institut für Astronomie (MPIA), Max-Planck-Gesellschaft-Max-Planck-Gesellschaft-Friedrich-Schiller-Universität = Friedrich Schiller University Jena [Jena, Germany], Max-Planck-Gesellschaft, Institut des Sciences de la Terre (ISTerre), Institut Français des Sciences et Technologies des Transports, de l'Aménagement et des Réseaux (IFSTTAR)-Institut national des sciences de l'Univers (INSU - CNRS)-Institut de recherche pour le développement [IRD] : UR219-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), Institut des Sciences Moléculaires d'Orsay (ISMO), Université Paris-Sud - Paris 11 (UP11)-Centre National de la Recherche Scientifique (CNRS), Institut Jean Lamour (IJL), Institut de Chimie du CNRS (INC)-Université de Lorraine (UL)-Centre National de la Recherche Scientifique (CNRS), Institut Universitaire de France (IUF), Ministère de l'Education nationale, de l’Enseignement supérieur et de la Recherche (M.E.N.E.S.R.), European Project: 636829,H2020,ERC-2014-STG,PRIMCHEM(2015), Centre National de la Recherche Scientifique (CNRS)-Université Paris-Sud - Paris 11 (UP11), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut de recherche pour le développement [IRD] : UR206-Muséum national d'Histoire naturelle (MNHN)-Centre National de la Recherche Scientifique (CNRS), and Université de Lorraine (UL)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)
Subjects: 010504 meteorology & atmospheric sciences, Infrared, Astrophysics::High Energy Astrophysical Phenomena, Analytical chemistry, [SDU.ASTR.EP]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], Infrared spectroscopy, FOS: Physical sciences, 01 natural sciences, law.invention, law, 0103 physical sciences, X-rays, Irradiation, 010303 astronomy & astrophysics, Instrumentation and Methods for Astrophysics (astro-ph.IM), 0105 earth and related environmental sciences, Physics, High Energy Astrophysical Phenomena (astro-ph.HE), extinction, [SDU.ASTR.SR]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Solar and Stellar Astrophysics [astro-ph.SR], protoplanetary disks, Astronomy and Astrophysics, Tholin, Synchrotron, Secondary ion mass spectrometry, Interstellar medium, Deuterium, 13. Climate action, Space and Planetary Science, Astrophysics::Earth and Planetary Astrophysics, dust, Astrophysics - Instrumentation and Methods for Astrophysics, Astrophysics - High Energy Astrophysical Phenomena
Abstract: The deuterium enrichment of organics in the interstellar medium, protoplanetary disks and meteorites has been proposed to be the result of ionizing radiation. The goal of this study is to quantify the effects of soft X-rays (0.1 - 2 keV), a component of stellar radiation fields illuminating protoplanetary disks, on the refractory organics present in the disks. We prepared tholins, nitrogen-rich complex organics, via plasma deposition and used synchrotron radiation to simulate X-ray fluences in protoplanetary disks. Controlled irradiation experiments at 0.5 and 1.3 keV were performed at the SEXTANTS beam line of the SOLEIL synchrotron, and were followed by ex-situ infrared, Raman and isotopic diagnostics. Infrared spectroscopy revealed the loss of singly-bonded groups (N-H, C-H and R-N$\equiv$C) and the formation of sp$^3$ carbon defects. Raman analysis revealed the introduction of defects and structural amorphization. Finally, tholins were measured via secondary ion mass spectrometry (SIMS), revealing that significant D-enrichment is induced by X-ray irradiation. Our results are compared to previous experimental studies involving the thermal degradation and electron irradiation of organics. The penetration depth of soft X-rays in $\mu$m-sized tholins leads to volume rather than surface modifications: lower energy X-rays (0.5 keV) induce a larger D-enrichment than 1.3 keV X-rays, reaching a plateau for doses larger than 5 $\times$ 10$^{27}$ eV cm$^{-3}$. Our work provides experimental evidence of a new non-thermal pathway to deuterium fractionation of organic matter., Comment: 14 pages, 23 figures. Accepted for publication in ApJ
Published: 2017
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19. Goldschmidt Abstracts 2009 – W

Author: Frédéric Foucher, Sue Wirick, Sandrine Villette, P. Dumas, Frances Westall, Frédéric Jamme, A. Jauss, Gordon Southam, Laurence Lemelle, François Robert, Jan Toporski, L. Laclean, Alexandre Simionovici, Yves Marrocchi, Murielle Salomé, B. Cavalazzi, S. Mostafaoui, and Anders Meibom
Subjects: Elemental composition, Geochemistry and Petrology, Chemistry, Environmental chemistry, In situ analysis, Microbial mat
Published: 2009
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20. Goldschmidt Abstracts 2009 – O

Author: Pierre Beck, Bernard Schmitt, Eric Quirico, V. De Andrade, François-Régis Orthous-Daunay, Sylvie Derenne, Alexandre Simionovici, and Laurence Lemelle
Subjects: chemistry.chemical_classification, 010506 paleontology, Mineralogy, 010502 geochemistry & geophysics, 01 natural sciences, Hydrothermal circulation, Astrobiology, chemistry, 13. Climate action, Geochemistry and Petrology, Chondrite, Organic matter, Geology, 0105 earth and related environmental sciences
Abstract: CI1, CM2, CR2 and ungrouped C2 carbonaceous chondrites contain a few percent of insoluble organic matter (IOM) which could provide clues on the organic chemistry of nebular and/or protostellar environments. These chondrites also have experienced complex hydrothermal processes on parent bodies [1-3]. A major issue is the understanding of IOM compositional and structural changes due to hydrothermalism. Chemical variability has been reported among various IOMs, and so far interpreted as the consequence of oxidation processes [4; 5]. The primordial diversity of organic precursors could be also involved.
Published: 2009
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21. In situ imaging of organic sulfur in 700–800 My-old Neoproterozoic microfossils using X-ray spectromicroscopy at the S K-edge

Author: Philippe Labrot, Murielle Salomé, Alexandre Simionovici, Laurence Lemelle, Michel Viso, and Frances Westall
Subjects: In situ, 010504 meteorology & atmospheric sciences, Proterozoic, chemistry.chemical_element, Mineralogy, X-ray fluorescence, 010502 geochemistry & geophysics, 01 natural sciences, Sulfur, XANES, Biogeology, Precambrian, chemistry.chemical_compound, chemistry, Geochemistry and Petrology, Kerogen, Geology, 0105 earth and related environmental sciences
Abstract: The study of very ancient microfossils has recently raised contentious issues regarding interpretation of the biogenicity of the structures. In situ investigation of certain elements such as sulfur within potential microfossils is a powerful complement to other methods of investigation that can provide valuable information on biogenicity. We present here a first such study on Precambrian microfossils from the 700–800-My-old Neoproterozoic Draken Formation, Svalbard, using scanning X-ray microscopy (SXM) in the fluorescence mode and X-ray absorption near edge spectroscopy (XANES) at the sulfur K-edge. SXM allowed mapping of up to 300 ppm of probably endogenous sulfur within the kerogenous walls of Myxococcoides chlorelloidea microfossils. XANES showed that the sulfur is most likely contained in heterocyclic organic compounds, such as thiophene(s).
Published: 2008
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22. Picking nannofossils: How and why

Author: Baptiste Suchéras-Marx, Fabienne Giraud, Alex Léna, Alexandre Simionovici, Centre européen de recherche et d'enseignement des géosciences de l'environnement (CEREGE), Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Collège de France (CdF (institution))-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut National de la Recherche Agronomique (INRA), Institut des Sciences de la Terre (ISTerre), Institut Français des Sciences et Technologies des Transports, de l'Aménagement et des Réseaux (IFSTTAR)-Institut national des sciences de l'Univers (INSU - CNRS)-Institut de recherche pour le développement [IRD] : UR219-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), Sciences et Société, Historicité, Éducation et Pratiques (EA S2HEP), École normale supérieure - Lyon (ENS Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon, Institut de Recherche pour le Développement (IRD)-Institut National de la Recherche Agronomique (INRA)-Aix Marseille Université (AMU)-Collège de France (CdF (institution))-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Collège de France (CdF)-Institut national des sciences de l'Univers (INSU - CNRS)-Aix Marseille Université (AMU)-Institut National de la Recherche Agronomique (INRA), Université Grenoble Alpes (UGA)-Centre National de la Recherche Scientifique (CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-PRES Université de Grenoble-Institut de recherche pour le développement [IRD] : UR219-Institut national des sciences de l'Univers (INSU - CNRS)-Institut Français des Sciences et Technologies des Transports, de l'Aménagement et des Réseaux (IFSTTAR)-Université Joseph Fourier - Grenoble 1 (UJF), Institut de Recherche pour le Développement (IRD)-Aix Marseille Université (AMU)-Collège de France (CdF (institution))-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Institut national des sciences de l'Univers (INSU - CNRS)-Institut de recherche pour le développement [IRD] : UR219-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Gustave Eiffel-Université Grenoble Alpes (UGA), Laboratoire de Géologie de Lyon - Terre, Planètes, Environnement (LGL-TPE), and Université de Lyon-Université de Lyon-Institut national des sciences de l'Univers (INSU - CNRS)-Université Jean Monnet - Saint-Étienne (UJM)-Centre National de la Recherche Scientifique (CNRS)
Subjects: 010506 paleontology, 0303 health sciences, 010504 meteorology & atmospheric sciences, biology, Paleontology, 010502 geochemistry & geophysics, biology.organism_classification, 01 natural sciences, Associate editor, Foraminifera, 03 medical and health sciences, Protocol design, [SDU]Sciences of the Universe [physics], Early phase, [SDU.STU.PG]Sciences of the Universe [physics]/Earth Sciences/Paleontology, Geology, ComputingMilieux_MISCELLANEOUS, 030304 developmental biology, 0105 earth and related environmental sciences
Abstract: Calcareous nannofossils are a group of micrometric fossils abundantly found in marine sediments. This group is mainly composed of coccoliths, platelets produced by the unicellular algae coccolithophores, and nannoliths whose biological affinity remains unknown. Calcareous nannofossils have a continuous record for the past 215 myr (Bown 1998) and can be found in almost every marine environment from coast to open oceans and from the Equator to the poles in surface waters (Winter et al. 1994). These microfossils are also made of low-Mg calcite (Siesser 1977; Stoll et al. 2001) which is resistant to dissolution and a common matrix for geochemical analyses in palaeoceanography. Hence, calcareous nannofossils could be one of the best fossils for palaeoceanographical studies for the last 215 myr. Their use in geochemistry is, however, less common than planktic foraminifera due to their small sizes, masses (10–1000 pg) and complex vital effects. Despite the fact that nannofossils are very small (2–20 µm), the development of high-resolution analytical devices opens up the opportunity to analyse single nannofossils or even parts of them. This is a growing field of nannofossil research. We thank the ESRF scientific committee for selecting and funding the EC-811 experiment which needed a new protocol of nannofossil separation from the matrix. We are particularly grateful to Isabelle Daniel for scientific support, Christophe Chamot at PLATIM (ENS Lyon) for methodological help and to Polymicro Technologies™ who supplied us with free capillaries during the early phase of the protocol design. We finally thank the associate editor Emanuela Mattioli and reviewers Silvia Gardin and Tom Dunkley Jones for their constructive comments on the manuscript.
Published: 2016
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23. Chemical Forms of Mercury in Human Hair Reveal Sources of Exposure

Author: Jean-Paul Bourdineaud, Maria Gonzalez-Rey, Mauro Rovezzi, Pieter Glatzel, Kathryn L. Nagy, Mironel Enescu, Martine Lanson, Alexandre Simionovici, Alain Manceau, Rémi Tucoulou, manceau, alain, Institut des Sciences de la Terre (ISTerre), Institut Français des Sciences et Technologies des Transports, de l'Aménagement et des Réseaux (IFSTTAR)-Institut national des sciences de l'Univers (INSU - CNRS)-Institut de recherche pour le développement [IRD] : UR219-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), Laboratoire Chrono-environnement (UMR 6249) (LCE), Centre National de la Recherche Scientifique (CNRS)-Université de Franche-Comté (UFC), Université Bourgogne Franche-Comté [COMUE] (UBFC)-Université Bourgogne Franche-Comté [COMUE] (UBFC), Environnements et Paléoenvironnements OCéaniques (EPOC), Observatoire aquitain des sciences de l'univers (OASU), Université Sciences et Technologies - Bordeaux 1 (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Sciences et Technologies - Bordeaux 1 (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-École pratique des hautes études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS), European Synchrotron Radiation Facility (ESRF), Institut Européen de Chimie et Biologie (IECB), Université de Bordeaux (UB)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS), Minéralogie et environnements, Institut des Sciences de la Terre ( ISTerre ), Université Grenoble Alpes ( UGA ) -Centre National de la Recherche Scientifique ( CNRS ) -Université Savoie Mont Blanc ( USMB [Université de Savoie] [Université de Chambéry] ) -PRES Université de Grenoble-Institut de recherche pour le développement [IRD] : UR219-Institut national des sciences de l'Univers ( INSU - CNRS ) -Institut Français des Sciences et Technologies des Transports, de l'Aménagement et des Réseaux ( IFSTTAR ) -Université Joseph Fourier - Grenoble 1 ( UJF ) -Université Grenoble Alpes ( UGA ) -Centre National de la Recherche Scientifique ( CNRS ) -Université Savoie Mont Blanc ( USMB [Université de Savoie] [Université de Chambéry] ) -PRES Université de Grenoble-Institut de recherche pour le développement [IRD] : UR219-Institut national des sciences de l'Univers ( INSU - CNRS ) -Institut Français des Sciences et Technologies des Transports, de l'Aménagement et des Réseaux ( IFSTTAR ) -Université Joseph Fourier - Grenoble 1 ( UJF ), Laboratoire Chrono-environnement ( LCE ), Université Bourgogne Franche-Comté ( UBFC ) -Centre National de la Recherche Scientifique ( CNRS ) -Université de Franche-Comté ( UFC ), Université Grenoble Alpes ( UGA ) -Centre National de la Recherche Scientifique ( CNRS ) -Université Savoie Mont Blanc ( USMB [Université de Savoie] [Université de Chambéry] ) -PRES Université de Grenoble-Institut de recherche pour le développement [IRD] : UR219-Institut national des sciences de l'Univers ( INSU - CNRS ) -Institut Français des Sciences et Technologies des Transports, de l'Aménagement et des Réseaux ( IFSTTAR ) -Université Joseph Fourier - Grenoble 1 ( UJF ), ESRF-GILDA, European Synchrotron Radiation Facility ( ESRF ), Department of Earth and Environmental Sciences [Chicago] ( EAES ), University of Illinois at Chicago ( UIC ), Environnements et Paléoenvironnements OCéaniques ( EPOC ), Observatoire aquitain des sciences de l'univers ( OASU ), Université Sciences et Technologies - Bordeaux 1-Institut national des sciences de l'Univers ( INSU - CNRS ) -Centre National de la Recherche Scientifique ( CNRS ) -Université Sciences et Technologies - Bordeaux 1-Institut national des sciences de l'Univers ( INSU - CNRS ) -Centre National de la Recherche Scientifique ( CNRS ) -École pratique des hautes études ( EPHE ) -Centre National de la Recherche Scientifique ( CNRS ), Laboratoire Chrono-environnement - CNRS - UBFC (UMR 6249) (LCE), Université de Franche-Comté (UFC), Université Bourgogne Franche-Comté [COMUE] (UBFC)-Université Bourgogne Franche-Comté [COMUE] (UBFC)-Centre National de la Recherche Scientifique (CNRS), Université Sciences et Technologies - Bordeaux 1-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Sciences et Technologies - Bordeaux 1-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-École pratique des hautes études (EPHE), Université Sciences et Technologies - Bordeaux 1 (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Sciences et Technologies - Bordeaux 1 (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-École Pratique des Hautes Études (EPHE), Institut Français des Sciences et Technologies des Transports, de l'Aménagement et des Réseaux (IFSTTAR)-Institut national des sciences de l'Univers (INSU - CNRS)-Institut de recherche pour le développement [IRD] : UR219-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut Français des Sciences et Technologies des Transports, de l'Aménagement et des Réseaux (IFSTTAR)-Institut national des sciences de l'Univers (INSU - CNRS)-Institut de recherche pour le développement [IRD] : UR219-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), Laboratoire Chrono-environnement - CNRS - UFC (UMR 6249) (LCE), Department of Earth and Environmental Sciences [Chicago] (EAES), University of Illinois [Chicago] (UIC), and University of Illinois System-University of Illinois System
Subjects: spectroscopy, Absorption spectroscopy, chemistry.chemical_element, Atmospheric mercury, Food Contamination, 02 engineering and technology, 010501 environmental sciences, 01 natural sciences, chemistry.chemical_compound, Ethylmercury, [CHIM] Chemical Sciences, Environmental Chemistry, Animals, Humans, [CHIM]Chemical Sciences, Methylmercury, 0105 earth and related environmental sciences, Fishes, hair, General Chemistry, Mercury, Contamination, Methylmercury Compounds, 021001 nanoscience & nanotechnology, Dental amalgams, Inorganic mercury, XANES, Mercury (element), [CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistry, [CHIM.THEO] Chemical Sciences/Theoretical and/or physical chemistry, chemistry, Seafood, speciation, Environmental chemistry, [ CHIM.THEO ] Chemical Sciences/Theoretical and/or physical chemistry, 0210 nano-technology, Environmental Monitoring
Abstract: International audience; Humans are contaminated by mercury in different forms from different sources. In practice, contamination by methylmercury from fish consumption is assessed by measuring hair mercury concentration, whereas exposure to elemental and inorganic mercury from other sources is tested by analysis of blood or urine. Here, we show that diverse sources of hair mercury at concentrations as low as 0.5 ppm can be individually identified by specific coordination to C, N, and S ligands with high energy-resolution X-ray absorption spectroscopy. Methylmercury from seafood, ethylmercury used as a bactericide, inorganic mercury from dental amalgams, and exogenously derived atmospheric mercury bind in distinctive intermolecular configurations to hair proteins, as supported by molecular modeling. A mercury spike located by X-ray nanofluorescence on one hair strand could even be dated to removal of a single dental amalgam. Chemical forms of other known or putative toxic metals in human tissues could be identified by this approach with potential broader applications to forensic, energy, and materials science.
Published: 2016
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24. Hard X-ray irradiation of cosmic silicate analogs: structural evolution and astrophysical implications

Author: T Sabri, Damien Salomon, E. Foy, Cornelia Jäger, Lisseth Gavilan, Jean-Louis Lemaire, Alexandre Simionovici, Th. Henning, S. Yagoubi, Gema Martínez-Criado, Institut d'astrophysique spatiale (IAS), Université Paris-Sud - Paris 11 (UP11)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Max-Planck-Institut für Astronomie (MPIA), Max-Planck-Gesellschaft, Institut des Sciences de la Terre (ISTerre), Institut Français des Sciences et Technologies des Transports, de l'Aménagement et des Réseaux (IFSTTAR)-Institut national des sciences de l'Univers (INSU - CNRS)-Institut de recherche pour le développement [IRD] : UR219-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), Institut des Sciences Moléculaires d'Orsay (ISMO), Centre National de la Recherche Scientifique (CNRS)-Université Paris-Sud - Paris 11 (UP11), Laboratoire Archéomatériaux et Prévision de l'Altération (LAPA - UMR 3685), Nanosciences et Innovation pour les Matériaux, la Biomédecine et l'Energie (ex SIS2M) (NIMBE UMR 3685), Institut Rayonnement Matière de Saclay (IRAMIS), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Institut Rayonnement Matière de Saclay (IRAMIS), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC), IRAMAT - Laboratoire Métallurgies et Cultures (IRAMAT - LMC), Institut de Recherches sur les Archéomatériaux (IRAMAT), Université de Technologie de Belfort-Montbeliard (UTBM)-Université d'Orléans (UO)-Université Bordeaux Montaigne-Centre National de la Recherche Scientifique (CNRS)-Université de Technologie de Belfort-Montbeliard (UTBM)-Université d'Orléans (UO)-Université Bordeaux Montaigne-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Etudes des Eléments Légers (LEEL - UMR 3685), European Synchrotron Radiation Facility (ESRF), Université Paris-Sud - Paris 11 (UP11)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Centre National d’Études Spatiales [Paris] (CNES), Université Paris-Sud - Paris 11 (UP11)-Centre National de la Recherche Scientifique (CNRS), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut Rayonnement Matière de Saclay (IRAMIS), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), and Université de Technologie de Belfort-Montbeliard (UTBM)-Université d'Orléans (UO)-Université Bordeaux Montaigne (UBM)-Centre National de la Recherche Scientifique (CNRS)-Université de Technologie de Belfort-Montbeliard (UTBM)-Université d'Orléans (UO)-Université Bordeaux Montaigne (UBM)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Astrochemistry, 010504 meteorology & atmospheric sciences, Evolution, Astrophysics::High Energy Astrophysical Phenomena, Interstellar cloud, Analytical chemistry, FOS: Physical sciences, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, 01 natural sciences, chemistry.chemical_compound, ISM: evolution, analytical [Methods], 0103 physical sciences, Irradiation, Methods: analytical, High-resolution transmission electron microscopy, Instrumentation and Methods for Astrophysics (astro-ph.IM), 010303 astronomy & astrophysics, Astrophysics::Galaxy Astrophysics, Dust, extinction, 0105 earth and related environmental sciences, Cosmic dust, Earth and Planetary Astrophysics (astro-ph.EP), Physics, extinction, Astronomy and Astrophysics, [CHIM.MATE]Chemical Sciences/Material chemistry, Silicate, Methods: laboratory: solid state, Amorphous solid, ISM: dust, chemistry, laboratory: solid state [Methods], Space and Planetary Science, Crystallite, Astrophysics::Earth and Planetary Astrophysics, Astrophysics - Instrumentation and Methods for Astrophysics, Astrophysics - Earth and Planetary Astrophysics
Abstract: [Context] Protoplanetary disks, interstellar clouds, and active galactic nuclei contain X-ray-dominated regions. X-rays interact with the dust and gas present in such environments. While a few laboratory X-ray irradiation experiments have been performed on ices, X-ray irradiation experiments on bare cosmic dust analogs have been scarce up to now., [Aims] Our goal is to study the effects of hard X-rays on cosmic dust analogs via in situ X-ray diffraction. By using a hard X-ray synchrotron nanobeam, we seek to simulate cumulative X-ray exposure on dust grains during their lifetime in these astrophysical environments and provide an upper limit on the effect of hard X-rays on dust grain structure., [Methods] We prepared enstatite (MgSiO3) nanograins, which are analogs to cosmic silicates, via the melting-quenching technique. These amorphous grains were then annealed to obtain polycrystalline grains. These were characterized via scanning electron microscopy (SEM) and high-resolution transmission electron microscopy (HRTEM) before irradiation. Powder samples were prepared in X-ray transparent substrates and were irradiated with hard X-rays nanobeams (29.4 keV) provided by beamline ID16B of the European Synchrotron Radiation Facility (Grenoble). X-ray diffraction images were recorded in transmission mode, and the ensuing diffractograms were analyzed as a function of the total X-ray exposure time., [Results] We detected the amorphization of polycrystalline silicates embedded in an organic matrix after an accumulated X-ray exposure of 6.4 × 1027 eV cm-2. Pure crystalline silicate grains (without resin) do not exhibit amorphization. None of the amorphous silicate samples (pure and embedded in resin) underwent crystallization. We analyze the evolution of the polycrystalline sample embedded in an organic matrix as a function of X-ray exposure., [Conclusions] Loss of diffraction peak intensity, peak broadening, and the disappearance of discrete spots and arcs reveal the amorphization of the resin embedded (originally polycrystalline) silicate sample. We explore the astrophysical implications of this laboratory result as an upper limit to the effect of X-rays on the structure of cosmic silicates.
Published: 2016
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25. Perspectives on heterococcolith geochemical proxies based on high-resolution X-ray fluorescence mapping

Author: Alexandre Simionovici, Fabienne Giraud, Isabelle Daniel, Rémi Tucoulou, Baptiste Suchéras-Marx, Laboratoire de Géologie de Lyon - Terre, Planètes, Environnement (LGL-TPE), École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut national des sciences de l'Univers (INSU - CNRS)-Université Jean Monnet - Saint-Étienne (UJM)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Magmas et Volcans (LMV), Institut national des sciences de l'Univers (INSU - CNRS)-Université Jean Monnet - Saint-Étienne (UJM)-Institut de Recherche pour le Développement et la société-Université Clermont Auvergne [2017-2020] (UCA [2017-2020])-Centre National de la Recherche Scientifique (CNRS)-Observatoire de Physique du Globe de Clermont-Ferrand (OPGC), Institut national des sciences de l'Univers (INSU - CNRS)-Université Clermont Auvergne [2017-2020] (UCA [2017-2020])-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Clermont Auvergne [2017-2020] (UCA [2017-2020])-Centre National de la Recherche Scientifique (CNRS), Centre européen de recherche et d'enseignement des géosciences de l'environnement (CEREGE), Institut de Recherche pour le Développement (IRD)-Institut National de la Recherche Agronomique (INRA)-Aix Marseille Université (AMU)-Collège de France (CdF (institution))-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Institut des Sciences de la Terre (ISTerre), Institut Français des Sciences et Technologies des Transports, de l'Aménagement et des Réseaux (IFSTTAR)-Institut national des sciences de l'Univers (INSU - CNRS)-Institut de recherche pour le développement [IRD] : UR219-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), European Synchrotron Radiation Facility (ESRF), Laboratoire de Géologie de Lyon - Terre, Planètes, Environnement [Lyon] (LGL-TPE), École normale supérieure - Lyon (ENS Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Institut national des sciences de l'Univers (INSU - CNRS)-Université Jean Monnet [Saint-Étienne] (UJM)-Institut de Recherche pour le Développement et la société-Université Clermont Auvergne (UCA)-Centre National de la Recherche Scientifique (CNRS)-Observatoire de Physique du Globe de Clermont-Ferrand (OPGC), Institut national des sciences de l'Univers (INSU - CNRS)-Université Clermont Auvergne (UCA)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Collège de France (CdF)-Institut national des sciences de l'Univers (INSU - CNRS)-Aix Marseille Université (AMU)-Institut National de la Recherche Agronomique (INRA), Université Grenoble Alpes (UGA)-Centre National de la Recherche Scientifique (CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-PRES Université de Grenoble-Institut de recherche pour le développement [IRD] : UR219-Institut national des sciences de l'Univers (INSU - CNRS)-Institut Français des Sciences et Technologies des Transports, de l'Aménagement et des Réseaux (IFSTTAR)-Université Joseph Fourier - Grenoble 1 (UJF), Institut national des sciences de l'Univers (INSU - CNRS)-Université Jean Monnet [Saint-Étienne] (UJM)-Institut de Recherche pour le Développement et la société-Université Clermont Auvergne [2017-2020] (UCA [2017-2020])-Centre National de la Recherche Scientifique (CNRS)-Observatoire de Physique du Globe de Clermont-Ferrand (OPGC), Centre National de la Recherche Scientifique (CNRS)-Université Clermont Auvergne [2017-2020] (UCA [2017-2020])-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Clermont Auvergne [2017-2020] (UCA [2017-2020])-Institut national des sciences de l'Univers (INSU - CNRS), and Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Collège de France (CdF (institution))-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut National de la Recherche Agronomique (INRA)
Subjects: 010504 meteorology & atmospheric sciences, Mineralogy, X-ray fluorescence, Synchrotron radiation, 010502 geochemistry & geophysics, 01 natural sciences, Homogeneous distribution, Calcium Carbonate, chemistry.chemical_compound, [SDU.STU.GC]Sciences of the Universe [physics]/Earth Sciences/Geochemistry, Ecology, Evolution, Behavior and Systematics, 0105 earth and related environmental sciences, General Environmental Science, Calcite, Portugal, Fossils, Haptophyta, Spectrometry, X-Ray Emission, Elements, Fluorescence, Diagenesis, Calcium carbonate, chemistry, General Earth and Planetary Sciences, Seawater, [SDU.STU.PG]Sciences of the Universe [physics]/Earth Sciences/Paleontology
Abstract: International audience; Heterococcoliths are micron-scale calcite platelets produced by coccolithophores. They have been the most abundant and continuous fossil record over the last 215 million years (Myr), offering great potential for geochemical studies, although the heterococcolith fossil record remains underutilised in this domain. We have mapped heterococcoliths' composition using X-ray fluorescence (XRF) with a 100-nm resolution beam to decipher element distributions in heterococcoliths and to investigate the potential development of geochemical proxies for palaeoceanography. The study presents two Middle Jurassic Watznaueria britannica heterococcoliths from Cabo Mondego, Portugal. XRF analysis was performed with a 17 keV incident energy beam at the European Synchrotron Radiation Facility ID22NI beamline to study elements from Sr down to S. Ca, Sr and Mn are distributed following the heterococcolith crystalline arrangement. Cl, Br and S display an homogeneous distribution, whereas K, Fe, Cu, Zn and Rb are concentrated at the edges and in the central area of the heterococcoliths. Distributions of K, Fe, Ti, Fe, Cu, Zn, Rb and to a lesser extent V and Cr are highly influenced by clay contamination and peripheral diagenetic overgrowth. Mn is related to diagenetic Mn-rich CaCO3 overgrowth on top of or between heterococcoliths shields. Cl and Br are likely to be present in heterococcoliths inside interstitial nano-domains. We assume that the cytoplasm [Cl−] and [Br−] are mediated and constant during heterococcolithogenesis. Assuming a linear correlation between cytoplasm [Cl−] and sea water [Cl−], heterococcolith Cl may have potential as a salinity proxy. As S is incorporated into heterococcoliths by sulphated polysaccharides, our study suggests a role for such polysaccharides in heterococcolithogenesis for at least 170 Myr. The low Sr/Ca in the W. britannica specimens studied here may either highlight an unusual cellular physiology of Mesozoic coccolithophores or result from low growth rates in oligotrophic environments.
Published: 2016
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26. In situmapping of high-pressure fluids using hydrothermal diamond anvil cells

Author: Bénédicte Ménez, D. Massare, Andrea Somogyi, L. Daudin, Hélène Bureau, M. Bonnin-Mosbah, Alexandre Simionovici, Valérie Malavergne, Hicham Khodja, Jean-Paul Gallien, and Cliff S. J. Shaw
Subjects: Quenching, In situ, Materials science, Aqueous solution, Analytical chemistry, Synchrotron radiation, Mineralogy, Condensed Matter Physics, Diamond anvil cell, Synchrotron, Hydrothermal circulation, Silicate, law.invention, chemistry.chemical_compound, chemistry, law
Abstract: We present new results combining high pressures and temperatures attainable in a diamond anvil cell with in situ synchrotron radiation induced micro-X-ray fluorescence measurements. Hydrothermal diamond anvil cells experiments have been performed by measuring the partitioning of Pb between aqueous fluids (pure water or NaCl-enriched water) and hydrous silicate melts of haplogranite composition using synchrotron X-ray fluorescence. The in situ measurements were performed in the range 0.3–1.2 GPa and 730–850 °C both in the aqueous fluid and in the silicate melts being in equilibrium. Pb is strongly partitioned into high-pressure–temperature hydrous melts when Cl is present in either the hydrous melt or the aqueous fluid. Moreover, our comparisons of in situ results with post-mortem results show that significant changes take place during rapid quenching especially when samples are small (few hundred of microns in diameter). Water exsolution is induced by the quench in the silicate melt showing the high mobil...
Published: 2007
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27. Constraints on the formation environment of two chondrule-like igneous particles from Comet 81P/Wild 2

Author: Gary R. Huss, Tolek Tyliszczak, Julien Stodolna, K. Nagashima, Ryan C. Ogliore, Zack Gainsforth, David J. Joswiak, Andrew J. Westphal, Alexandre Simionovici, Anna L. Butterworth, and Donald E. Brownlee
Subjects: Metamorphic rock, Comet, Chondrule, Liquidus, Astrophysics, Article, Astrobiology, Igneous rock, Geophysics, medicine.anatomical_structure, Interplanetary dust cloud, Meteorite, Space and Planetary Science, medicine, Iris (anatomy), Geology
Abstract: Using chemical and petrologic evidence and modeling, we deduce that two chondrule-like particles named Iris and Callie, from Stardust cometary track C2052,12,74, formed in an environment very similar to that seen for type II chondrules in meteorites. Iris was heated near liquidus, equilibrated, and cooled at ≤ 100 °C/hr and within ≈ 2 log units of the IW buffer with a high partial pressure of Na such as would be present with dust enrichments of ≈ 10(3). There was no detectable metamorphic, nebular or aqueous alteration. In previous work Ogliore et al. (2012) reported that Iris formed late, > 3 Myr after CAIs, assuming (26)Al was homogenously distributed, and was rich in heavy oxygen. Iris may be similar to assemblages found only in interplanetary dust particles and Stardust cometary samples called Kool particles. Callie is chemically and isotopically very similar but not identical to Iris.
Published: 2015

28. Standardless quantification of single fluid inclusions using synchrotron radiation induced X-ray fluorescence

Author: Bénédicte Ménez, Pierre Bleuet, Jean Cauzid, Pascal Philippot, Andrea Somogyi, Alexandre Simionovici, Institut de Physique du Globe de Paris (IPGP), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-IPG PARIS-Université Paris Diderot - Paris 7 (UPD7)-Université de La Réunion (UR)-Centre National de la Recherche Scientifique (CNRS), European Synchrotron Radiation Facility (ESRF), Synchrotron SOLEIL (SSOLEIL), Centre National de la Recherche Scientifique (CNRS), École normale supérieure - Lyon (ENS Lyon), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Université de La Réunion (UR)-Institut de Physique du Globe de Paris (IPG Paris)-Centre National de la Recherche Scientifique (CNRS), École normale supérieure de Lyon (ENS de Lyon), Synchrotron Soleil, DiffAbs beamline, Saint-Aubin, BP 48, 91192 Gif-sur-Yvette Cedex, France (SYNCHROTRON SOLEIL, DIFFABS BEAMLINE, SAINT-AUBIN, BP 48, 91192 GIF-SUR-YVETTE CEDEX, FRANCE), and Synchrotron Soleil, DiffAbs beamline, Saint-Aubin, BP 48, 91192 Gif-sur-Yvette Cedex, France
Subjects: Synchrotron radiation, Chemistry, 010401 analytical chemistry, X-ray fluorescence, Analytical chemistry, Geology, 010502 geochemistry & geophysics, Fluid inclusion, 01 natural sciences, Fluorescence, 0104 chemical sciences, Transition metal, Geochemistry and Petrology, Yield (chemistry), Calibration, Fluid inclusions, Inclusion (mineral), Quantitative analysis, 0105 earth and related environmental sciences
Abstract: International audience; Fluid inclusions are studied using synchrotron radiation induced μ-X-ray fluorescence (μ-SR-XRF). We analyse inclusions from the Brusson gold deposit, Italy. Several two-phase (liquid plus gas) inclusions of a single generation are used to compare a new standardless quantification procedure to previously published internal and external standardisation procedures. The three procedures are based on an infinite homogeneous plane layer and the calculations are performed with a non-iterative fundamental parameter method. Results show a good agreement between the average of the calculated concentrations obtained with the three procedures and the corresponding crush-leach analysis. Cl, K, Ca, Fe, Cu, Zn and As crush-leach concentrations are within error bars of the μ-SR-XRF concentration estimates. Br crush-leach content is above μ-SR-XRF estimates. Ti, Cr, Mn, Ni and Pb were detected with μ-SR-XRF technique only. These elements show different concentrations from one inclusion to another, suggesting heterogeneous trapping of tiny, infra-microscopic solid phases. The good correspondence between the results obtained using the three calibration procedures show that accurate standardless quantitative analysis of individual fluid inclusions is achievable. Statistical error calculation of the three procedures shows that the standardless quantification method yields more accurate results than the internal or external standard procedures. Uncertainties on inclusion depths strongly affect calculated light element concentrations (Cl to Ca), whereas Mn and heavier elements concentration estimates are more sensitive to errors on fluid inclusion thickness. Uncertainties of ± 1 μm or less on fluid inclusion thickness and depth yield statistical errors of not, vert, similar 50% on Cl concentration estimates and lower than 20% on transition metals. This new standardless-μ-SR-XRF based quantification procedure is more precise than the previously established ones and is efficiently applied to multielementary analysis (Cl to Pb) of diluted individual fluid inclusions.
Published: 2006
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29. Synchrotron X-Ray Microfluorescence and Microspectroscopy: Application and Perspectives in Materials Science

Author: Xavier Biquard, Gema Martínez-Criado, Sylvain Bohic, Alexandre Simionovici, Jean Susini, European Synchrotron Radiation Facility (ESRF), Laboratoire de Sciences de la Terre (LST), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-École normale supérieure - Lyon (ENS Lyon), Service de Physique des Matériaux et Microstructures (SP2M - UMR 9002), Institut Nanosciences et Cryogénie (INAC), Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), and Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])
Subjects: [PHYS]Physics [physics], Materials science, business.industry, General Chemical Engineering, 010401 analytical chemistry, Energy Engineering and Power Technology, 02 engineering and technology, 021001 nanoscience & nanotechnology, 01 natural sciences, Synchrotron, 0104 chemical sciences, Characterization (materials science), Insertion device, law.invention, Micrometre, Fuel Technology, Optics, law, Photon beams, X ray microfluorescence, 0210 nano-technology, business, Absorption (electromagnetic radiation), Storage ring
Abstract: International audience; Recent developments in synchrotron storage ring technology, insertion device design and X-ray optics provide polarized photon beams with unprecedented intensity and brilliance on a microscopic area. Various arrangements allow micrometer size hard X-ray beams with enough flux to undertake elemental mapping of trace elements then easily associated with micro-diffraction or micro-extended X-ray absorption fine structure studies on the very same sample region of interest. These analytical possibilities and the sensitivity and accuracy of the achieved analysis can complement or surpass other available instrumental micro-analytical methods. Such microprobes are becoming a very interesting tool for material characterization.
Published: 2005
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30. Size effects on the structure and phase transition behavior of baddeleyite TiO2

Author: Vladimir Dmitriev, Falko Langenhorst, Varghese Swamy, Leonid Dubrovinsky, Alexandre Simionovici, Natalia Dubrovinskaia, H.-P. Weber, and Michael Drakopoulos
Subjects: Phase transition, Anatase, Materials science, Mineralogy, General Chemistry, Crystal structure, Condensed Matter Physics, Nanocrystalline material, Baddeleyite, Nanocrystal, Chemical physics, Materials Chemistry, Crystallite, Science, technology and society
Abstract: High-pressure structural transitions in nanocrystalline systems are of significant interest as models of first-order phase transitions. We demonstrate size-induced lattice expansion and significant atomic rearrangements in the crystal structure of nanocrystalline high-pressure baddeleyite-TiO2. The α-PbO2 structured TiO2 recovered after dozens of pressure cycles in the α-PbO2-baddeleyite pressure field displayed elongate 25–35 nm crystallites, compared to starting 34-nm anatase crystallites, suggesting crystallite coherency across anatase, baddeleyite, and α-PbO2 structures and ‘single structural domain’ behavior of the nanocrystalline system.
Published: 2005
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31. ID22: a multitechnique hard X-ray microprobe beamline at the European Synchrotron Radiation Facility

Author: Gema Martínez-Criado, Alexandre Simionovici, Andrea Somogyi, Sylvain Bohic, Jean Cauzid, Rémi Tucoulou, Pierre Bleuet, and Alejandro Homs
Subjects: Air Pollutants, Optics and Photonics, Nuclear and High Energy Physics, Radiation, Micrometer scale, business.industry, Spectrometry, X-Ray Emission, Synchrotron radiation, Equipment Design, Undulator, X ray instrumentation, Optics, X-Ray Diffraction, Beamline, X ray microprobe, Materials Testing, Hard X-radiation, business, Instrumentation, Synchrotrons, Fluorescence tomography
Abstract: The ID22 beamline is dedicated to hard X-ray microanalysis allowing the combination of fluorescence, spectroscopy, diffraction and tomography techniques in a wide energy range from 6 to 70 keV. The recent installation of an in-vacuum undulator, a new sample stage and the adaptation of various focusing optics has contributed to a great improvement in the capabilities of the beamline, which is now accessed by a wide user community issued from medical, earth and environmental science, archaeology and material science. Many applications requiring low detection limits for localization/speciation of trace elements together with structural analysis have been developed at the beamline on the (sub)micrometer scale. The possibility of combining simultaneously different analytical probes offers the opportunity of a thorough study of a given sample or scientific problem. This paper presents a review of the recent developments of the beamline and a detailed description of its capabilities through examples from different fields of applications.
Published: 2005
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32. X-ray tomography: how to evaluate the reconstruction quality?

Author: Marina Chukalina, Bruno Golosio, Alexandre Simionovici, and Harald Funke
Subjects: Algebraic Reconstruction Technique, Tomographic reconstruction, Correlation coefficient, Radon transform, Wavelet transform, Iterative reconstruction, Atomic and Molecular Physics, and Optics, Imaging phantom, Analytical Chemistry, Tomography, Instrumentation, Algorithm, Spectroscopy, Mathematics
Abstract: Different reconstruction techniques are used to reconstruct the distribution of the physical characteristics, describing a sample under investigation, from a set of tomographic projections. We present a technique for the evaluation of the reconstruction quality. The technique is based on the comparison of two images (phantom and reconstructed image) by means of the correlation coefficient and of the mean square error between them. In parallel, the correlation coefficient and mean square error are calculated for the wavelet transforms of the phantom and reconstructed images. The scales for the wavelet transform are chosen in agreement with the major geometric parameters of the phantom. Then the correlation coefficient of the wavelet transform with the chosen scale yields an evaluation of the quality of the phantom parameters reconstruction. The accuracy of the parameters reconstruction is determined by the mean square error for the selected scale. The phantom used for the analysis is a medium with randomly distributed grains. The distribution is characterized by two parameters: grain size and grain density (average number of grains per unit area). The parameters are used as the scales for the wavelet transform calculation. We make a comparison of the Algebraic Reconstruction Technique (ART) and the Filtered Back Projection Algorithm.
Published: 2004
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33. FOCAL: X-ray optics for accurate spectroscopy

Author: F. Nolden, B. Franzke, O. Klepper, D. Banas, Alexandre Simionovici, St. König, Martino Trassinelli, Th. Stöhlker, K. Beckert, A. Orsic-Muthig, O. Wehrhan, Dieter Liesen, M. Steck, A. Gumberidze, D. Protic, X. L. Ma, D. Sierpowski, J. Bojowald, H.-J. Kluge, U. Popp, H. F. Beyer, Paul Indelicato, S. Tachenov, A. Warczak, Eckhart Förster, C. Kozhuharov, F. Bosch, S. Hagmann, Z. Stachura, E. Ziegler, P. Beller, Joanna Hoszowska, U. Spillmann, I. Mohos, and B. Manil
Subjects: Physics, X-ray spectroscopy, Range (particle radiation), business.industry, Astrophysics::High Energy Astrophysical Phenomena, X-ray optics, Radiation, Atomic and Molecular Physics, and Optics, Analytical Chemistry, Ion, Optics, Crystal optics, Crystal spectrometer, Spectroscopy, business, Instrumentation
Abstract: A crystal spectrometer has been constructed in the Focusing Compensated Asymmetric Laue geometry covering the energy range between 30 and 120 keV. We summarize the crystal optics and show the usefulness of the instrument for spectroscopy of stationary and fast moving X-ray sources. Results are reported from several tests employing a 169 Yb gamma-ray source and the Lyman radiation of one-electron Au 78+ ions travelling at a velocity corresponding to β = v / c o ≈0.44.
Published: 2004
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34. A library for X-ray–matter interaction cross sections for X-ray fluorescence applications

Author: Andrea Somogyi, Antonio Brunetti, M. Sanchez del Rio, Bruno Golosio, and Alexandre Simionovici
Subjects: Anomalous scattering, business.industry, Chemistry, Scattering, Interface (computing), Compton scattering, X-ray fluorescence, Photoionization, Fluorescence, Atomic and Molecular Physics, and Optics, Analytical Chemistry, Computational physics, Software, Optics, business, Instrumentation, Spectroscopy
Abstract: Quantitative estimate of elemental composition by spectroscopic and imaging techniques using X-ray fluorescence requires the availability of accurate data of X-ray interaction with matter. Although a wide number of computer codes and data sets are reported in literature, none of them is presented in the form of freely available library functions which can be easily included in software applications for X-ray fluorescence. This work presents a compilation of data sets from different published works and an xraylib interface in the form of callable functions. Although the target applications are on X-ray fluorescence, cross sections of interactions like photoionization, coherent scattering and Compton scattering, as well as form factors and anomalous scattering functions, are also available.
Published: 2004
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35. A new nondestructive X-ray method for the determination of the 3D mineralogy at the micrometer scale

Author: Christophe Rau, Philippe Gillet, Alexandre Simionovici, Robert Truche, Laurence Lemelle, and Marina Chukalina
Subjects: Olivine, Scanning electron microscope, Resolution (electron density), Analytical chemistry, Mineralogy, X-ray fluorescence, engineering.material, Synchrotron, Silicate, law.invention, Micrometre, chemistry.chemical_compound, Geophysics, chemistry, Geochemistry and Petrology, law, Attenuation coefficient, engineering, Geology
Abstract: The combination of synchrotron-based X-ray absorption and fluorescence computed tomographies (CT) is a new method allowing a noninvasive and nondestructive determination of the three-dimensional (3D) mineralogy with micrometer resolution of sub-millimeter silicate grains, possibly stored in a silica holder. These CT were performed with beams of a few tens of keV from a third-generation synchrotron source on one olivine grain of the NWA817 Martian meteorite presenting a reddish alteration phase. The reconstructed sections show a network of fractures and a few micrometer-thick layers formed on one grain. The 3D facet orientation and the X-ray attenuation coefficient indicate that this grain is an Fo44±9 olivine crystal. The fluorescence section reveals rims enriched in Fe (a major element) or depleted in Ca (a minor element). This CT combination shows that the micrometer-thick layer is preferentially formed on the (010) olivine face and has a lower density (3.5 ± 0.4 g/cm3 ) than the olivine, even though it is enriched in Fe. Its complex nano-petrography and the distributions of nanometer-sized voids and fractures in such a micrometer thick layer, first observed by scanning electron microscopy on focused ion-beam cuts, is not shown by CT. The precision presently achieved, although moderate, is sufficient to obtain a 3D semi-quantitative view of the mineralogy consistent with the one previously established by electron probe microanalyses (Sautter et al. 2002).
Published: 2004
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36. X-ray Fluorescence Tomography of Individual Municipal Solid Waste and Biomass Fly Ash Particles

Author: Maria Caterina Camerani, Alexandre Simionovici, Andrea Somogyi, Britt-Marie Steenari, Bruno Golosio, and Itai Panas
Subjects: Microprobe, Municipal solid waste, Chemistry, Analytical chemistry, Spectrometry, X-Ray Emission, Synchrotron radiation, X-ray fluorescence, Microbeam, Coal Ash, Carbon, Analytical Chemistry, Incineration, Adsorption, Fly ash, Calcium, Environmental Pollutants, Particulate Matter, Particle Size, Tomography, X-Ray Computed, Synchrotrons, Cadmium, Environmental Monitoring
Abstract: Information about Cd distribution inside single municipal solid waste and biomass fly ash particles is fundamental since it affects its leachability. The internal 2D distributions of the main and trace elements in such highly inhomogeneous matrixes were successfully determined by means of the combined synchrotron radiation induced micro X-ray fluorescence (micro-SRXRF) and tomography (micro-SRXRFT) techniques. Scanning micro-SRXRF measurements show Cd elemental distribution within single fly ash particles to be inhomogeneous, but no information can be obtained about its internal distribution. During micro-SRXRFT analysis, single fly ash particles are successively measured by a rotational-translational scan in a VH=2 x 5 microm2 microbeam. The 2D internal elemental distribution images, obtained by the modified simultaneous algebraic reconstruction technique algorithm, provide the size and the location of Cd-containing areas together with the location of other measurable elements. Results showed Cd concentration to be higher in the core of the fly ash particles analyzed rather than on the surface of the particles. Moreover, in both ashes, Ca-containing matrixes are found to be the main Cd-bearing phases. A possible mechanism for Cd adsorption on the fly ash particles is proposed based on the obtained results.
Published: 2004
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37. A new natural, super-hard, transparent polymorph of carbon from the Popigai impact crater, Russia

Author: Varghese Swamy, Ahmed El Goresy, Leonid Dubrovinsky, Michael Drakopoulos, Günther Graup, Victor L Masaitis, Alexandre Simionovici, Smail Mostefaoui, and Philippe Gillet
Subjects: Diffraction, Materials science, Popigai, Lonsdaleite, Mineralogy, X-ray fluorescence, Hexagonal Diamond, Transformation, law.invention, natural super hard carbon polymorph, Impact crater, law, Shock Compression, shock-induced phase transition, Graphite, lonsdaleite, Room-Temperature Compression, Raman-Scattering, Global and Planetary Change, Space group, Spectra, Synchrotron, Crystallography, Phase, X-ray crystallography, General Earth and Planetary Sciences, Pressures
Abstract: A natural shockwave event led to the formation of a new crystalline polymorph of carbon in gneisses from the Popigai crater, Russia. The new species occupies the interior of a multiphase assemblage and is entirely enveloped by lonsdaleite and graphite. Polishing hardness of this new phase is greater than that of lonsdaleite. Micro-beam synchrotron X-ray diffraction, imaging and fluorescence studies revealed a pure transparent carbon phase. The diffraction pattern is indexed in terms of a cubic cell (a = 14.697 Angstrom, space group Pm3m.). This species was neither encountered in static or dynamic high-pressure experiment nor predicted by theoretical calculations. (C) 2003 Published by Editions scientifiques et medicales Elsevier SAS on behalf of Academie des sciences.
Published: 2003
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38. Internal elemental microanalysis combining x-ray fluorescence, Compton and transmission tomography

Author: Marina Chukalina, Andrea Somogyi, Antonio Brunetti, Bruno Golosio, Alexandre Simionovici, Laurence Lemelle, European Synchrotron Radiation Facility (ESRF), Laboratoire de Sciences de la Terre (LST), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-École normale supérieure - Lyon (ENS Lyon), École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), and Université de Lyon-Université de Lyon-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)
Subjects: General Physics and Astronomy, X-ray fluorescence, Synchrotron radiation, 02 engineering and technology, tomography, 01 natural sciences, law.invention, martian meteorite, symbols.namesake, Optics, law, synchrotron, Rayleigh scattering, Physics, business.industry, Scattering, 010401 analytical chemistry, Compton scattering, 021001 nanoscience & nanotechnology, Synchrotron, 0104 chemical sciences, X-ray Fluorescence, Beamline, symbols, Tomography, 0210 nano-technology, business, [SDU.STU.MI]Sciences of the Universe [physics]/Earth Sciences/Mineralogy
Abstract: Conventional x-ray transmission tomography provides the spatial distribution of the absorption coefficient inside a sample. Other tomographic techniques, based on the detection of photons coming from fluorescent emission, Compton and Rayleigh scattering, are used for obtaining information on the internal elemental composition of the sample. However, the reconstruction problem for these techniques is generally much more difficult than that of transmission tomography, mainly due to self-absorption effects in the sample. In this article an approach to the reconstruction problem is presented, which integrates the information from the three types of signals. This method provides the quantitative spatial distribution of all elements that emit detectable fluorescent lines (Z15 in usual experimental conditions), even when the absorption effects are strong, and the spatial distribution of the global density of the lighter elements. The use of this technique is demonstrated on the reconstruction of a grain of the martian meteorite NWA817, mainly composed of low Z elements not measured in fluorescence and for which this method provides a unique insight. The measurement was done at the ID22 beamline of the European Synchrotron Radiation Facility.
Published: 2003
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39. X-ray imaging techniques and exobiology

Author: Christoph Rau, Marina Chukalina, Bruno Golosio, Philippe Gillet, Phil M. Oger, Laurence Lemelle, Jean Susini, and Alexandre Simionovici
Subjects: business.industry, General Physics and Astronomy, Mineralogy, Synchrotron radiation, X-ray fluorescence, Silicate, Synchrotron, law.invention, chemistry.chemical_compound, Optics, chemistry, law, Coincident, Extraterrestrial life, Tomography, business, Absorption (electromagnetic radiation)
Abstract: X-ray imaging techniques at the best spatial resolution and using synchrotron facilities are put forth as powerful techniques for the search of small life forms in extraterrestrial rocks under quarantine conditions. Absorption and fluorescence X-ray microtomographies on sub-millimeter silicate assemblages inside a container reveal the mineralogical microenvironments were life should be looked for in priority. Limitations with respect to bacterial detection are due to the difficulties to obtain information about light elements (Z less than or equal to 14), major constituents of biological and silicate samples. The X-ray signature of a "present" bacteria on a silicate surface was defined by X-ray mapping, out of a container, as coincident micrometer and oval zones having strong P and S fluorescence lines (S-fluorescence being slightly lower than P-fluorescence) and an amino-linked sulfur redox speciation. The detection of a single cell along with new procedures to calculate tomographic views will allow considerable improvements of 3D detection of life by X-ray techniques.
Published: 2003
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40. Lifetime Measurement of the Metastable 23P0State in Helium-like197Au

Author: S. Toleikis, Y. Zou, Zbigniew Stachura, Dieter Liesen, H. F. Beyer, R. W. Dunford, Xinwen Ma, Paul Indelicato, C. Kozhuharov, A. Gumberidze, E. Berdermann, M. Czanta, Thomas Stöhlker, Alexandre Simionovici, D. H. Schneider, Richard Marrus, A. Warczak, F. Bosch, and B. Manil
Subjects: Nuclear and High Energy Physics, Materials science, chemistry, Metastability, chemistry.chemical_element, Physical and Theoretical Chemistry, Atomic physics, Condensed Matter Physics, Atomic and Molecular Physics, and Optics, Helium
Published: 2003
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41. Effects of beamline components (undulator, monochromator, focusing device) on the beam intensity at ID18F (ESRF)

Author: Bart Vekemans, Andrea Somogyi, Alexandre Simionovici, Laszlo Vincze, Michael Drakopoulos, and Freddy Adams
Subjects: Physics, Nuclear and High Energy Physics, Microprobe, Physics::Instrumentation and Detectors, business.industry, Detector, Synchrotron radiation, Undulator, law.invention, Optics, Beamline, law, High-energy X-rays, Ionization chamber, business, Instrumentation, Monochromator
Abstract: The ID18F microprobe end-station of the European Synchrotron Radiation Facility (ESRF) is dedicated to precise and reproducible quantitative X-ray fluorescence analysis in the ppm level with ⩽5% accuracy for elements of Z ⩾19 and micron-size spatial resolution. In order to fulfill this requirement the precise monitoring and normalization of the intensity variation of the focused micro-beam is necessary. The various effects influencing the intensity variation, hence the stability of the μ-beam, were investigated by placing different detectors (miniature ionization chamber, photodiodes) into the monochromatic beam. The theoretical statistical error of the measured signal in each detector was estimated on the basis of the absorption and e − –ion-pair production processes and was compared with the measured statistical errors.
Published: 2003
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42. Compression behavior of nanocrystalline anatase TiO2

Author: Varghese Swamy, Michael Drakopoulos, Natalia Dubrovinskaia, H.-P. Weber, Leonid Dubrovinsky, Alexandre Simionovici, and Vladimir Dmitriev
Subjects: Diffraction, Anatase, Bulk modulus, Macrocrystalline, Materials science, Analytical chemistry, General Chemistry, Condensed Matter Physics, Nanocrystalline material, Synchrotron, law.invention, Crystallography, Nanocrystal, law, Materials Chemistry, Crystallite
Abstract: We present a synchrotron X-ray diffraction study of pressure-induced changes in nanocrystalline anatase (with a crystallite size of 30–40 nm) to 35 GPa. The nanoanatase was observed to a pressure above 20 GPa. Direct transformation to the baddeleyite-TiO 2 polymorph was seen at 18 GPa. A fit of the pressure versus volume data to a Birch–Murnaghan equation yielded the following parameters: zero-pressure volume, V 0 =136.15 A 3 , bulk modulus, K T =243(3) GPa, and the pressure derivative of bulk modulus, K ′=4 (fixed). The bulk modulus value obtained for the nanocrystalline anatase is about 35% larger than that of the macrocrystalline counterpart.
Published: 2003
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43. Wavelength-dispersive spectroscopy in the hard x-ray regime of a heavy highly-charged ion: The 1s Lamb shift in hydrogen-like gold

Author: P. M. Hillenbrand, E. Ziegler, Nicolas Winckler, N. Winters, U. Spillmann, Renate Märtin, N. Petridis, Martino Trassinelli, Ingo Uschmann, Paweł P. Jagodziński, F. Nolden, Christina Dimopoulou, S. Trotsenko, Dariusz Banaś, M. S. Sanjari, Michael Lestinsky, Yu. A. Litvinov, H.F. Beyer, A. Gumberidze, Csilla I. Szabo, M. Schwemlein, K. S. Schulze, T. Kämpfer, Robert E. Grisenti, R. Heß, Danyal Winters, G. Weber, B. Manil, Paul Indelicato, T. Gassner, Eckhart Förster, Christophor Kozhuharov, R. Loetzsch, Wanqiu Chen, K.-H. Blumenhagen, Thomas Stöhlker, S. Hagmann, Dieter Liesen, O. Wehrhan, C. Brandau, F. Bosch, M. Steck, Alexandre Simionovici, Helmholtz zentrum für Schwerionenforschung GmbH (GSI), Agrégats et surfaces sous excitations intenses (INSP-E10), Institut des Nanosciences de Paris (INSP), Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS), Institute of Physics [Kielce], Jan Kochanowski University, Institut für Optik und Quantenelektronik, Institut fur Optik und Quantenelektronik, Laboratoire Kastler Brossel (LKB (Jussieu)), Fédération de recherche du Département de physique de l'Ecole Normale Supérieure - ENS Paris (FRDPENS), Centre National de la Recherche Scientifique (CNRS)-École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Kielce University of Technology, Laboratoire de Physique des Lasers (LPL), Université Paris 13 (UP13)-Centre National de la Recherche Scientifique (CNRS), Institut des Sciences de la Terre (ISTerre), Institut Français des Sciences et Technologies des Transports, de l'Aménagement et des Réseaux (IFSTTAR)-Institut national des sciences de l'Univers (INSU - CNRS)-Institut de recherche pour le développement [IRD] : UR219-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), European Project: 262010,EC:FP7:INFRA,FP7-INFRASTRUCTURES-2010-1,ENSAR(2010), and École normale supérieure - Paris (ENS-PSL)
Subjects: Hydrogen, 0785Nc, QUANTUM ELECTRODYNAMICS TEST, Atomic Physics (physics.atom-ph), HELIUM-LIKE, URANIUM, General Physics and Astronomy, chemistry.chemical_element, FOS: Physical sciences, X-RAY SPECTROSCOPY, STORAGE RINGS, 01 natural sciences, 010305 fluids & plasmas, Ion, 3130J, Physics - Atomic Physics, PHYSICS, high-Z ions, Wavelength-dispersive X-ray spectroscopy, 3230Rj Keywords: X-ray spectrometer, 1220Fv, COOLER, 0103 physical sciences, ENERGY-DISPERSIVE, numbers: 0785Fv, ddc:530, Crystal optics, micro-strip detector, 010306 general physics, Spectroscopy, Physics, QED, [PHYS.PHYS.PHYS-ATOM-PH]Physics [physics]/Physics [physics]/Atomic Physics [physics.atom-ph], Highly charged ion, storage ring, Lamb shift, chemistry, STRONG COULOMB FIELD, Atomic physics, Storage ring, TRANSITION
Abstract: New journal of physics 20(7), 073033 (2018). doi:10.1088/1367-2630/aad01d, Published by IOP, [London]
Published: 2018
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44. Crystal optics for precision x-ray spectroscopy on highly charged ions-conception and proof

Author: S. Hagmann, M. Schwemlein, C. Brandau, T. Kämpfer, O. Wehrhan, Wanqiu Chen, C. Dimopoulou, T. Gassner, Paul Indelicato, B. Manil, M. Steck, Csilla I. Szabo, U. Spillmann, Martino Trassinelli, Dariusz Banaś, N. Winters, A. Gumberidze, N. Petridis, S. Trotsenko, Ingo Uschmann, Renate Märtin, Th. Stöhlker, Danyal Winters, Yu. A. Litvinov, R. Heß, Kai S. Schulze, F. Bosch, Paweł P. Jagodziński, H. F. Beyer, F. Nolden, E. Ziegler, Nicolas Winckler, Eckhart Förster, Dieter Liesen, C. Kozhuharov, Michael Lestinsky, Robert E. Grisenti, Alexandre Simionovici, P. M. Hillenbrand, R. Loetzsch, G. Weber, M. S. Sanjari, K.-H. Blumenhagen, Institut des Nanosciences de Paris (INSP), Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS), European Community [262010], Helmholtz Alliance [HA216/EMMI], HIC-for-FAIR through HGS-HIRe, and Helmholtz-CAS Joint Research Group [HCJRG-108]
Subjects: Physics, X-ray spectroscopy, Spectrometer, QED, business.industry, chemistry.chemical_element, X-ray optics, Germanium, storage ring, x-ray spectroscopy, Condensed Matter Physics, Atomic and Molecular Physics, and Optics, Crystal, Optics, chemistry, x-ray optics, ddc:530, Crystal optics, [PHYS.COND]Physics [physics]/Condensed Matter [cond-mat], business, Spectroscopy, Nuclear Experiment, heavy ions, Storage ring
Abstract: International audience; The experimental investigation of quantum-electrodydamic contributions to the binding energies of inner shells of highly charged heavy ions requires an accurate spectroscopy in the region of hard x-rays suitable at a limited source strength. For this purpose the focusing compensated asymmetric Laue crystal optics has been developed and a twin-spectrometer assembly has been built and commissioned at the experimental storage ring of the GSI Helmholtzzentrum Darmstadt. We characterize the crystal optics and demonstrate the usefulness of the instrumentation for accurate spectroscopy of both stationary and fast moving x-ray sources. The experimental procedures discussed here may also be applied for other spectroscopic studies where a transition from conventional germanium x-ray detectors to crystal spectrometers seems too demanding because of low source intensity.
Published: 2015
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45. The rheological behaviour of fracture-filling cherts: example of Barite Valley dikes, Barberton Greenstone Belt, South Africa

Author: Nicholas Arndt, Ronan Ledevin, A. Davaille, Morgane Ledevin, Alexandre Simionovici, Ecologie et évolution des populations, Département écologie évolutive [LBBE], Laboratoire de Biométrie et Biologie Evolutive - UMR 5558 (LBBE), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut National de Recherche en Informatique et en Automatique (Inria)-VetAgro Sup - Institut national d'enseignement supérieur et de recherche en alimentation, santé animale, sciences agronomiques et de l'environnement (VAS)-Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut National de Recherche en Informatique et en Automatique (Inria)-VetAgro Sup - Institut national d'enseignement supérieur et de recherche en alimentation, santé animale, sciences agronomiques et de l'environnement (VAS)-Centre National de la Recherche Scientifique (CNRS)-Laboratoire de Biométrie et Biologie Evolutive - UMR 5558 (LBBE), Université de Lyon-Université de Lyon-Institut National de Recherche en Informatique et en Automatique (Inria)-VetAgro Sup - Institut national d'enseignement supérieur et de recherche en alimentation, santé animale, sciences agronomiques et de l'environnement (VAS)-Centre National de la Recherche Scientifique (CNRS), Institut des Sciences de la Terre (ISTerre), Institut national des sciences de l'Univers (INSU - CNRS)-Institut de recherche pour le développement [IRD] : UR219-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Gustave Eiffel-Université Grenoble Alpes (UGA), Fluides, automatique, systèmes thermiques (FAST), and Université Paris-Sud - Paris 11 (UP11)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Thixotropy, Dike, 010504 meteorology & atmospheric sciences, Stratigraphy, Archean, Country rock, [SDV]Life Sciences [q-bio], Geochemistry, Soil Science, Greenstone belt, 010502 geochemistry & geophysics, 01 natural sciences, lcsh:Stratigraphy, Geochemistry and Petrology, lcsh:QE640-699, 0105 earth and related environmental sciences, Earth-Surface Processes, geography, geography.geographical_feature_category, lcsh:QE1-996.5, Paleontology, Geology, Crust, lcsh:Geology, Geophysics, Slurry, Clay minerals
Abstract: In the Barberton Greenstone Belt, South Africa, a 100–250 m thick complex of carbonaceous chert dikes marks the transition from the Mendon Formation to the Mapepe Formation (3260 Ma). The sub-vertical- to vertical position of the fractures, the abundance of highly shattered zones with poorly rotated angular fragments and common jigsaw fit, radial structures, and multiple injection features point to repetitive hydraulic fracturing that released overpressured fluids trapped within the shallow crust. The chemical and isotopic compositions of the chert favour a model whereby seawater-derived fluids circulated at low temperature (< 100–150 °C) within the shallow crust. From the microscopic structure of the chert, the injected material was a slurry of abundant clay-sized, rounded particles of silica, carbonaceous matter and minor clay minerals, all suspended in a siliceous colloidal solution. The dike geometry and characteristics of the slurry concur on that the chert was viscoelastic, and most probably thixotropic at the time of injection: the penetration of black chert into extremely fine fractures is evidence for low viscosity at the time of injection and the suspension of large country rock fragments in the chert matrix provides evidence of high viscosity soon thereafter. We explain the rheology by the particulate and colloidal structure of the slurry, and by the characteristic of silica suspensions to form cohesive 3-D networks through gelation. Our results provide valuable information about the compositions, physical characteristics and rheological properties of the fluids that circulated through Archean volcano-sedimentary sequences, which is an additional step to understand conditions on the floor of Archean oceans, the habitat of early life.
Published: 2015
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46. Liquid metal penetration at grain boundaries: Characterization by synchrotron radiation micro-radiography and micro-fluorescence

Author: D. Bellet, N. Marie, J. Ouillier, K. Wolski, Christoph Rau, J. Teyssier, Alexandre Simionovici, and Wolfgang Ludwig
Subjects: Crystallography, X ray radiography, Chemistry, Time resolved spectra, Analytical chemistry, General Physics and Astronomy, Synchrotron radiation, Grain boundary, Fluorescence
Abstract: La penetration des metaux liquides aux joints de grains de metaux solides en l'absence de contrainte exterieure peut, pour un certain nombre de couples specifiques, conduire a la fragilisation du solide. Nous presentons dans ce papier deux techniques d'imagerie synchrotron qui sont bien adaptees pour observer ce type de phenomene. La micro-radiographie synchrotron a ete utilisee pour caracteriser la cinetique de penetration pour le couple Al/Ga. Nous montrons que la version moderne de radiographie par absorption possede la resolution spatiale et temporelle adequate pour etudier la penetration de films sub-microniques de Ga liquide localises aux joints de grains de bicristaux d'aluminium. La micro-fluorescence synchrotron est quant a elle bien adaptee pour la detection de traces d'elements dans des systemes tres dilues. Au detriment de la resolution spatiale et temporelle, cette technique permet la detection de quantites infimes d'atomes diffusant aux joints de grains de metaux solides.
Published: 2002
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47. Synchrotron radiation as a tool for in situ investigation of extraterrestrial grains in low-density collectors: application to the analyses of the PIE polymid foams targets

Author: Yves Langevin, P Chevallier, Janet Borg, Pierre-Ivan Raynal, Alexandre Simionovici, and Eric Quirico
Subjects: Materials science, Opacity, business.industry, Synchrotron radiation, Astronomy and Astrophysics, Synchrotron, law.invention, Optics, Space and Planetary Science, law, Extraterrestrial life, Particle, business, Chemical composition, Visible spectrum, Space debris
Abstract: The Particle Impact Experiment (PIE) was flown for 11 months outside the MIR station in 1996–97. The grains, both of extraterrestrial and terrestrial origins, captured in the low-density foam collectors, were investigated for using Synchrotron X-ray microfluorescence (SXμF) techniques, developed at LURE (Orsay, France) and ESRF (Grenoble, France). The positions of grains a few microns large are known at better than 10 μm . Chemical identification is arduous; only Z>20 elements are identified and, for the heavy elements, only a rough estimate of their abundances inside the grains can be given. We use the Fe/Ni ratio as the criterion allowing to distinguish between terrestrial orbital debris (OD) and extraterrestrial grains. In the 60 cm 2 of foam analyzed by this technique, we identified two or three probable extraterrestrial grains and confirmed the existence of an OD cloud, rich in Fe–Ni alloys, crossed by the MIR station. SXμF is a powerful, non-destructive, technique of in situ identification of absorbing grains trapped in a material otherwise transparent to X-rays. It is the only analytical procedure for foams, opaque to visible light. For aerogels, exposed in many space missions and used as grain collectors in the STARDUST mission, the grains positions can be known after an optical scanning; SXμF appears as the last step for the high resolution in situ identification (size, shape, chemical composition) of the grain before its eventual extraction by microtunneling techniques.
Published: 2002
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48. Iron oxidation states in silicate glass fragments and glass inclusions with a XANES micro-probe

Author: Philippe Dillmann, J.P. Duraud, Alexandre Simionovici, M. Bonnin-Mosbah, D. Massare, and Nicole Métrich
Subjects: Valence (chemistry), Olivine, Materials science, Resolution (electron density), Analytical chemistry, Mineralogy, Crystal growth, engineering.material, Condensed Matter Physics, XANES, Synchrotron, Spectral line, Electronic, Optical and Magnetic Materials, law.invention, law, Materials Chemistry, Ceramics and Composites, engineering, Absorption (chemistry)
Abstract: The iron oxidation states and its environment in volcanic silicate glasses have been studied by combining micro-X-ray absorption near edge structure (XANES) experiments at the iron K-edge in silicate glass fragments and glass inclusions trapped during the crystal growth. Experiments were performed at the ESRF (ID22 beam-line) – a third generation synchrotron – using a focused beam (2×10 μm 2 ) together with a high brilliance and a good energy resolution. The selected silicate glasses, basaltic in composition, contain between 5.5 and 8 wt% total Fe. In all XANES spectra, pre-peaks exhibit a multi-component structure, which is the convolution of information related to the valence state of iron (2+,3+), the site geometry and transition types. The Fe3+/ΣFe ratio of silicate glass fragments deduced from the XANES spectra is correlated to values determined by chemistry on bulk samples within the range 0.05–0.85. XANES spectra from glass inclusions hosted in natural olivine crystals may be interpreted considering the glass fragments as reference samples.
Published: 2001
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49. Synchrotron X-ray micro-beam studies of ancient Egyptian make-up

Author: Michel Anne, Michel Dubus, Joseph Salomon, Ph. Walter, Pauline Martinetto, Michael Drakopoulos, Eric Dooryhee, and Alexandre Simionovici
Subjects: Nuclear and High Energy Physics, Materials science, Mineral, Trace element, Mineralogy, engineering.material, Microanalysis, XANES, Synchrotron, law.invention, Absorption edge, Impurity, Galena, law, engineering, Instrumentation
Abstract: Vases full of make-up are most often present in the burial furniture of Egyptian tombs dated from the pharaonic period. The powdered cosmetics made of isolated grains are analysed to identify their trace element signature. From this signature we identify the provenance of the mineral ingredients in the make-up and we observe different impurities in products, which have been demonstrated as synthetic substances by previous works. Focused X-ray micro-beam ( 2×5 μm 2 ) is successively tuned at 11 keV, below the LIII absorption edge of Pb, and 31.8 keV for global characterisation of the metal impurities. The fluorescence signal integrated over each single grain is detected against the X-ray micro-diffraction pattern collected in transmission with a bi-dimensional detector. Furthermore, for galena grains rich in Zn, the XANES signal at the K-absorption edge of Zn shows its immediate nearest-neighbour environment.
Published: 2001
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50. Synchrotron-induced X-ray microfluorescence on single cells

Author: Anatoly Snigirev, Dominique Heymann, Christian G. Schroer, Richard Ortega, Sylvain Bohic, and Alexandre Simionovici
Subjects: Nuclear and High Energy Physics, Microprobe, Materials science, Photon, business.industry, X-ray fluorescence, Microanalysis, Collimated light, Synchrotron, law.invention, Biological specimen, Optics, law, business, Instrumentation, Beam (structure)
Abstract: Recent improvements in synchrotron X-ray sources (third generation) and in X-ray focusing elements have been realized. This result in delivering highly collimated quasi-monochromatic X-ray beams with tunable energy and beam focused down to sub-micrometer diameter. Preliminary results in the μ-SXRF of single cells were obtained in the hard X-ray range. “Pink”-beam and compound refractive lenses were used resulting in a 1×10 μm 2 (vertical×horizontal) beam size with a flux ∼5×10 10 photon/s / μm 2 . The experiment confirmed that high energy, high intensity X-rays were well suited for microanalysis of sensitive biological specimens such as freeze-dried cells. Results show that the synchrotron microprobe set-up at ESRF allows high sensitivity in trace element measurements for cells treated with pharmacological doses of an iodine-labeled anticancer drug.
Published: 2001
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