A5055248625- Geochemistry and Geologic Mapping
- Clay minerals and soil interactions
- Mineral Processing and Grinding
- Concrete and Cement Materials Research
- Geological and Geochemical Analysis
- Hydrocarbon exploration and reservoir analysis
- Soil and Unsaturated Flow
- Heavy metals in environment
- Geophysical and Geoelectrical Methods
- Mineralogy and Gemology Studies
- Geological Modeling and Analysis
- Layered Double Hydroxides Synthesis and Applications
- Iron oxide chemistry and applications
- Magnesium Oxide Properties and Applications
- Building materials and conservation
- Water Quality and Pollution Assessment
- Groundwater and Isotope Geochemistry
- Concrete Properties and Behavior
- Geochemistry and Elemental Analysis
- Mine drainage and remediation techniques
- Groundwater flow and contamination studies
- Grouting, Rheology, and Soil Mechanics
- Electron and X-Ray Spectroscopy Techniques
- Remote-Sensing Image Classification
- Spectroscopy and Chemometric Analyses
Bureau de Recherches Géologiques et Minières
2016-2025
Université d'Orléans
2023
Institut des Matériaux Jean Rouxel
2016
Nantes Université
2016
Centre National de la Recherche Scientifique
2016
Institut Français
2014-2016
Winston-Salem State University
2010
University of Aberdeen
2010
Understanding calcium silicate hydrates (CSHs) is of paramount importance for understanding the behavior cement materials because they control most properties these man-made materials. The atomic scale water content and structure have a major influence on their properties, as analogous with clay minerals, we should assess these. Here, used multiple analytical approach to quantify distribution in CSH samples determine relative proportions sorbed external internal (interlayer) surfaces. Water...
Water in calcium silicate hydrate (C-S-H) is one of the key parameters driving macroscopic behavior cement materials for which water vapor partial pressure has an impact on Young's modulus and volumic properties. Several samples C-S-H with a bulk Ca/Si ratio ranging between 0.6 1.6 were characterized to study their dehydration/hydration under water-controlled conditions using29Si NMR, adsorption volumetry, X-ray diffraction, Fourier-transform near-infrared diffuse reflectance various...
Opalinus Clay is chosen as host rock for the deep geological disposal of nuclear waste in Switzerland and also being considered Germany. The underlying Staffelegg Formation comprises potentially water-bearing layers. To investigate hydrogeological setting these two formations at Swiss Rock Laboratory Mont Terri bore holes have been drilled framework HS-Experiment (Hydrogeological Survey). 58 m long BHS-1 starts Lower Shaly facies Clay, crossects entire formation ends Triassic Klettgau...
Abstract The long‐term behavior of high‐level radioactive waste glass depends on the mineralogical and geochemical interactions between various components multibarrier system, under geological repository conditions. present study focuses SON68 alteration in synthetic cement water at 50°C 70°C. While pH > 10, dissolution rates were lower when contacting than deionized water. This effect stems from high Ca concentration presence Si porewater. initial low reaction progress (3.4 ± 1.0 × 10 −2...
Swelling capacity of smectite was studied over decades regarding its application as barrier in disposal nuclear wastes geological repositories well the induced volume change potential soils according to moisture. In order improve our knowledge swelling smectite, a miniaturized oedometer developed combine pressure measurement with wide angle X-ray scattering (WAXS) characterization real time during hydration smectite. This coupled set up allowed studying saturation under confined condions and...
The redox reaction between natural Fe-containing clay minerals and its sorbates is a fundamental process controlling the cycles of many elements such as carbon, nutrients, redox-sensitive metals, metalloids (e.g., Co, Mn, As, Se), inorganic well organic pollutants in Earth's critical zone. While structure under oxic conditions well-known, less known about their behavior anoxic reducing conditions, thereby impeding full understanding mechanisms clay-driven reduction oxidation (redox)...
Abstract In the present study, chemical composition, mineralogy, and mechanisms of alteration a cementitious grout based on CEM III/C with addition smectite, hydrotalcite, silica fume, are studied using combination physical methods. This material was designed in context geological repository radioactive wastes, twofold aim: first, to fill technical voids left by drilling operations at interface between formation disposal galleries. Second, neutralize potential acidic transient due pyrite...
Mineral identification and quantification are key to the understanding and, hence, capacity predict material properties. The method of choice for mineral is powder X-ray diffraction (XRD), generally using a Rietveld refinement approach. However, successful requires preliminary phases that make up sample. This carried out manually, this task becomes extremely long or virtually impossible in case very large datasets such as those from synchrotron computed tomography. To circumvent issue,...
Co/Fe-based layered double hydroxides (LDHs) are among the most promising materials for electrochemical applications, particularly in development of energy storage devices, such as capacitors. They have also been demonstrated to function conversion catalysts photoelectrochemical applications CO2 into valuable chemicals. Understanding formation mechanisms compounds is therefore prime interest further controlling chemical composition, structure, morphology, and/or reactivity synthesized...
Organotin compounds are used as pesticides and fungicides well additives in plastics. This study identifies the de novo generation of novel volatile organotins municipal waste deposits their release via landfill gas. Besides tetramethyltin (Me4Sn), a strong neurotoxin, 5 previously reported organotins, 13 ethylated, propylated, butylated tetraalkyltin were identified. A concentration 2−4 μg Sn m−3 gas was estimated for two sites Scotland. The atmospheric stability Me4Sn methylated tin...
The mechanisms of selenate (SeO42–) sorption by Friedel's salt (AFm-Cl2), a layered double hydroxide phase found in (altered) cement-based materials, were studied using combination wet chemistry, electron probe, X-ray scattering, and transmission microscopy techniques. Flowing solution containing SeO42– through suspension AFm-Cl2 dedicated chemical reactor led to several crystallographic modifications that quantified geochemical modeling the chemistry data analysis diffraction scattering...