A5031216229- Geology and Paleoclimatology Research
- Geological and Geochemical Analysis
- Isotope Analysis in Ecology
- Marine and coastal ecosystems
- Maritime and Coastal Archaeology
- Nuclear materials and radiation effects
- Glass properties and applications
- Advanced Condensed Matter Physics
- Mineralogy and Gemology Studies
- Ancient and Medieval Archaeology Studies
- Multiferroics and related materials
- Luminescence Properties of Advanced Materials
- Archaeology and ancient environmental studies
- Marine and environmental studies
- Geochemistry and Geologic Mapping
- Magnetic and transport properties of perovskites and related materials
- earthquake and tectonic studies
- Paleontology and Stratigraphy of Fossils
- Geological and Geophysical Studies Worldwide
- Gold and Silver Nanoparticles Synthesis and Applications
- Marine Bivalve and Aquaculture Studies
- Geological and Geophysical Studies
- Planetary Science and Exploration
- Lichen and fungal ecology
- Copper-based nanomaterials and applications
Laboratoire de Planétologie et Géosciences
2015-2024
Centre National de la Recherche Scientifique
2009-2023
Le Mans Université
2023
Nantes Université
2009-2023
Université Nantes Angers Le Mans
2023
Université d'Angers
2018-2022
Observatoire des Sciences de l'Univers Nantes Atlantique
2015
Observatoire des sciences de l'Univers Paris-Saclay
2015
Institut des Matériaux Jean Rouxel
2009-2012
The substitution of lithium for copper in Cu2ZnSnS4 (CZTS) has been experimentally and theoretically investigated. Formally, the (Cu1–xLix)ZnSnS4 system exhibits two well-defined solid solutions. Indeed, single crystal structural analyses demonstrate that low (x < 0.4) high > 0.6) lithium-content compounds adopt kesterite structure wurtz-kesterite structure, respectively. For x between 0.4 0.6, aforementioned types coexist. Moreover, 119Sn NMR carried out on a (Cu0.7Li0.3)2ZnSnS4 sample...
Abstract. The adaptation of some benthic foraminiferal species to low-oxygen conditions provides the prospect using chemical composition their tests as proxies for bottom water oxygenation. Manganese may be particularly suitable such a geochemical proxy because this redox element is soluble in reduced form (Mn2+) and hence can incorporated into under conditions. Therefore, intra- inter-test differences Mn∕Ca ratios hold important information about short-term variability pore Mn2+...
Ceramic samples of MnW1–xMoxO4 (x ≤ 0.3) solid solution were prepared by a solid-state route with the goal increasing magnitude spin-exchange couplings among Mn2+ ions in spin spiral multiferroic MnWO4. Samples characterized X-ray diffraction, optical spectroscopy, magnetization, and dielectric permittivity measurements. It was observed that Néel temperature TN, ordering TM2, ferroelectric phase-transition TFE2 MnWO4 increased upon nonmagnetic substitution Mo6+ for W6+. Like pure MnWO4,...
The effects of substituting nonmagnetic Mg2+ and Zn2+ ions for the Mn2+ (S = 5/2) on structural, magnetic dielectric properties multiferroic frustrated antiferromagnet MnWO4 were investigated. Polycrystalline samples Mn1-xMgxWO4 Mn1-xZnxWO4 (0<x<0.3) solid solutions prepared by a solid-state route characterized via X-ray neutron diffraction, magnetization, permittivity measurements. Mg Zn substitutions give rise to very similar effects. Neel temperature TN, AF3-to-AF2 phase transition T2,...
Abstract Geological mapping in the Ogaden region of SE Ethiopia, integrated with aeromagnetic data, has revealed a large dyke swarm extending SSE more than 600 km from southern Afar margin across Somali Plate to Ethiopia–Somalia border. 40 Ar/ 39 Ar age dating shows that emplacement occurred at 24–27 Ma, contemporaneous early rifting and dyking Red Sea. Slab-pull forces generated Zagros subduction zone strained lithosphere Afro-Arabian plate, began extend south Sea c. 27 Afar, fed by...
Abstract In this work, we studied the hydrothermal agates from Neogene–Quaternary volcanic district of Allumiere-Tolfa, north-west Rome (Latium, Italy) using a combination micro-textural, spectroscopic, and geochemical data. The examined sample consists (1) an outer cristobalite layer deposited during early stages growth, (2) sequence chalcedonic bands (including i.e., length-fast, zebraic, minor length-slow chalcedony) with variable moganite content (up to ca. 48 wt%), (3) inner terminated...
Incorporation of iodine into high-pressure vitrified glasses is a strong function alkali content. The vitrification under conditions could represent potential solution for the immobilization 129 I radioisotopes.
Two recommendations are suggested for immobilizing 129 I radioisotopes in high-pressure glasses: the use of an oxidized iodine form (I 5+ ) instead reduced − and a sodium rich composition calcium one.
Abstract Martian basalts are different from Earth by their iron‐rich abundance with 18 wt% FeO tot in average for Mars upper crust. The H 2 O dissolution mechanism this atypical melt composition is not well understood. We have synthesized O‐bearing martian basaltic glass analogs (10 < 16 wt%) under high pressures (0.5–1.5 GPa) and temperatures (>1500°C) conditions. used Raman Fourier transform infrared spectroscopies to investigate the effect of as content on molecular structure...
Abstract. The adaptation of some benthic foraminiferal species to low oxygen conditions provides the prospect using chemical composition their tests as proxies for bottom water oxygenation. Manganese may be particularly suitable such a geochemical proxy, because this redox element is soluble in reduced form (Mn2+), and hence can incorporated into under conditions. Therefore, intra- inter-test differences Mn / Ca ratios hold important information about short term variability pore Mn2+...
This study presents new geochemical data on dolerites from the Plussulien and Beulin Neolithic quarries in Massif Armoricain (France) for dolerite samples their surrounding local regions. Using major trace element obtained these rocks, two regional occurrences appear to be clearly distinct. Consequently, a set of chemical criteria is proposed identify axes produced uniquely at quarry discriminate between region Beulin, but outside quarries, those Plussulien. These results could also used,...