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35 results on '"François Gensdarmes"'

1. Post-corona unipolar chargers with tuneable aerosol size-charge relations: Parameters affecting ion dispersion and particle trajectories for charger designs

Author

François Gensdarmes, A. Bouarouri, Jean-Pascal Borra, N. Jidenko, D. Boulaud, D. Maro, Laboratoire de physique des gaz et des plasmas (LPGP), Université Paris-Sud - Paris 11 (UP11)-Centre National de la Recherche Scientifique (CNRS), PSN-RES/SCA/LPMA, and Institut de Radioprotection et de Sûreté Nucléaire (IRSN)

Subjects
Materials science, 010504 meteorology & atmospheric sciences, aerosol, FOS: Physical sciences, 02 engineering and technology, Applied Physics (physics.app-ph), 01 natural sciences, complex mixtures, Ion, Corona (optical phenomenon), [PHYS.PHYS.PHYS-PLASM-PH]Physics [physics]/Physics [physics]/Plasma Physics [physics.plasm-ph], Physics::Plasma Physics, Dispersion (optics), diffusion charging, Environmental Chemistry, General Materials Science, [SPI.GPROC]Engineering Sciences [physics]/Chemical and Process Engineering, Diffusion (business), Physics::Atmospheric and Oceanic Physics, 0105 earth and related environmental sciences, size-charge relation, [SPI.PLASMA]Engineering Sciences [physics]/Plasmas, Charge (physics), Physics - Applied Physics, 021001 nanoscience & nanotechnology, Pollution, Physics - Plasma Physics, Aerosol, Plasma Physics (physics.plasm-ph), differential mobility analysis, Particle, Atomic physics, 0210 nano-technology, corona discharge
Abstract

This article focuses on the mean charge per particle of monodisperse submicron aerosols charged by the diffusion of unipolar ions in post-corona discharge. It aims to confirm and discuss the limits of considering a single value of Ni·t to describe aerosol charging and then to present methods to control the size-charge relation. Three aerosol chargers with different mixings of ion and aerosol flows are investigated. Despite comparable ion sources with discharge currents of a few tens of µA, the size-charge relations differ from one charger to another due to different ion-aerosol mixing conditions and subsequent differences in ion density along the particles’ trajectories. Discrepancies are even more noticeable as the particle size increases. Discharge current, velocities of ion and aerosol flows and the electric field control post-discharge ion density at each point of the charging zone. The control of particle trajectory in expanding unipolar ion clouds leads to tuneable size-charge relations. Aerosol inertia and charging dynamics both depend on particle size, affect the Ni·t experienced by the particle and thus the final charge of the particle. Operating conditions to reach a constant mean charge for particles larger than 200 nm are reported. Conclusions provide a basis to design aerosol chargers devoted to electric mobility selection for aerosol deposition, separation or electrical measurements, especially to overcome the limits of mobility-to-size data inversion due to the multiple charge ambiguity inherent to diffusion chargers. Copyright © 2020 American Association for Aerosol Research

Published
2020
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2. Evidence of inter-particles collision effect in airflow resuspension of poly-dispersed tungsten particles in monolayer deposits

Author

Jean-Christophe Sabroux, Ana Maria Vidales, Samuel Peillon, Anthony Rondeau, Rodolfo Omar Uñac, François Gensdarmes, Jesica Gisele Benito, Choplansky, PSN-RES/SCA/LPMA, Institut de Radioprotection et de Sûreté Nucléaire (IRSN), Universidad Nacional de San Luis [San Luis] (UNSL), and INFAP

Subjects
Fluid Flow and Transfer Processes, [PHYS]Physics [physics], Atmospheric Science, Environmental Engineering, Materials science, 010504 meteorology & atmospheric sciences, Mechanical Engineering, Airflow, chemistry.chemical_element, 010501 environmental sciences, Tungsten, 01 natural sciences, Pollution, Molecular physics, Bin, chemistry, Monolayer, Particle, Particle size, Shear velocity, 0105 earth and related environmental sciences, Wind tunnel
Abstract

Poly-dispersed particle resuspension by turbulent airflow was experimentally studied in a wind tunnel called BISE. The set-up was carefully validated to produce reference airflows with three absolute pressures and friction velocities values. Monolayer deposits of poly-dispersed tungsten particles on tungsten surfaces were used for the experiments. The fraction of detached particles by size bin from 1 μm to 50 μm was quantified to analyze the effects of friction velocity, absolute pressure and particles concentration on surface. Comparison of the results with Rock'n Roll and Monte-Carlo resuspension modeling revealed discrepancies for particles behavior with diameter below 4.5 μm. These discrepancies could not be understood by assessment of particle-surface adhesion force distribution carried out with Atomic Force Microscopy analysis. For particle surface concentrations ranging from 35 to 100 mm−2, a collision effect was identified due to the concentration and poly-dispersion of particles deposited on the surface. Indeed, when analyzing the experimental data, a good linear correlation is obtained between the fraction of the small particles detached and a collision parameter, demonstrating that collisions could be responsible for the unexpectedly high resuspended fraction observed for particle size below 4.5 μm in diameter. The experimental data and the analysis presented in the paper show that particle surface concentration and collision effects are clearly relevant and should be considered in the above-mentioned resuspension models, especially for poly-dispersed particles assessment.

Published
2020
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3. Adhesion of tungsten particles on rough tungsten surfaces using Atomic Force Microscopy

Author

Samuel Peillon, Cristian Stancu, Michaël Redolfi, A. Autricque, Christian Grisolia, Olivier Pluchery, François Gensdarmes, Institut de Radioprotection et de Sûreté Nucléaire (IRSN), Institut de Recherche sur la Fusion par confinement Magnétique (IRFM), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Laboratoire des Sciences des Procédés et des Matériaux (LSPM), Université Paris 13 (UP13)-Institut Galilée-Université Sorbonne Paris Cité (USPC)-Centre National de la Recherche Scientifique (CNRS), National Institute for Lasers, Plasma, and Radiation Physics [Magurele-Ilfov] (INFLPR), Institut des Nanosciences de Paris (INSP), and Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Atmospheric Science, Environmental Engineering, Materials science, 010504 meteorology & atmospheric sciences, Hamaker constant, chemistry.chemical_element, Surface finish, 010501 environmental sciences, Tungsten, 01 natural sciences, Micrometre, symbols.namesake, Composite material, 0105 earth and related environmental sciences, Fluid Flow and Transfer Processes, [PHYS.PHYS.PHYS-ATOM-PH]Physics [physics]/Physics [physics]/Atomic Physics [physics.atom-ph], Mechanical Engineering, Adhesion, Pollution, Roughness, Atomic Force Microscopy, Colloidal probe technique, chemistry, symbols, Particle size, van der Waals force
Abstract

International audience; Adhesion forces between tungsten spherical microparticles and tungsten substrates with different roughnesses have been measured using the Atomic Force Microscopy (AFM) colloidal probe technique. Mean roughnesses of the tungsten substrates were measured by AFM and were ranked in three categories i.e. nanoscale, sub-microscale and microscale roughnesses. Experimental Hamaker constant of 37 ± 3.5 × 10 −20 J has been obtained using a spherical tungsten particle of 10.5 µm in radius and a tungsten substrate with nanoscale root-mean-square roughness of rms = 11.5 nm. It was shown that larger roughness of the order rms = 712 nm induces a two order of magnitude decrease on the adhesion of tungsten microparticles compared to a smooth tungsten surface with nanoscale roughness. Comparison with the van der Waals-based adhesion force model of Rabinovich which integrates the roughness of surfaces showed good agreement with experimental pull-off forces even when roughness of the substrate is close to the micrometer range. In such case, measurements have shown that dependency of adhesion force with particle size (in the micrometer range) has a secondary influence compared to the roughness of surfaces.

Published
2019
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4. Evaluation of the nose-to-brain transport of different physico-chemical forms of uranium after exposure via inhalation of a UO4 aerosol in the rat

Author

Chrystelle Ibanez, Philippe Lestaevel, Audrey Roynette, Christelle Elie, Teni Ebrahimian, Bernadette Dhieux-Lestaevel, Karine Tack, Christine Tessier, François Gensdarmes, David Suhard, PRP-HOM/SRBE/LRTOX, Institut de Radioprotection et de Sûreté Nucléaire (IRSN), Laboratoire de Physique et de Métrologie des Aérosols (DSU/SERAC/LPMA), and Institut de Radioprotection et de SÛreté Nucléaire, IRSN

Subjects
Pollutant, Inhalation, Health, Toxicology and Mutagenesis, [SDV]Life Sciences [q-bio], Public Health, Environmental and Occupational Health, chemistry.chemical_element, 010501 environmental sciences, Uranium, Nose to brain, Particulates, 01 natural sciences, complex mixtures, Aerosol, 03 medical and health sciences, 0302 clinical medicine, chemistry, Air pollutants, 13. Climate action, Environmental chemistry, 030212 general & internal medicine, 0105 earth and related environmental sciences
Abstract

International audience; Background: Health risk issues are raised concerning inhalation of particulate pollutants that are thought to have potential hazardous effects in the central nervous system. The brain is presented as a direct target of particulate matter exposure because of the “nose-to-brain” pathway involvement. The main cause of contamination in nuclear occupational activities is related to exposure to aerosols containing radionuclides, in particular uranium dust. It has been previously demonstrated that instilled solubilized uranium in the rat nasal cavity is conveyed to the brain via the olfactory nerve. Objective: The aim of this study was to analyze the anatomical localization of uranium compounds in the olfactory system after in vivo exposure to a polydisperse aerosol of uranium tetraoxide (UO4) particles.Methods: The olfactory neuroepithelium and selected brain structuresolfactory bulbs, frontal cortex, hippocampus, cerebellum and brainstemwere microdissected four hours after aerosol inhalation via a nose-only system in adult rats. Tissues were subjected to complementary analytical techniques.Results: Uranium concentrations measured by ICP-MS were significantly higher in all brain structures from exposed animals compared to their respective controls. We observed that cerebral uranium concentrations followed an antero-posterior gradient with typical accumulation in the olfactory bulbs, characteristic of a direct olfactory transfer of inhaled compounds. Secondary Ion Mass Spectrometry microscopy and Transmission Electron Microscopy coupled to Energy Dispersive X-Ray spectroscopy were used in order to track elemental uranium in situ in the olfactory epithelium. Elemental uranium was detected in precise anatomical regions: olfactory neuron dendrites, paracellular junctions of neuroepithelial cells, olfactory nerve tracts (around axons and endoneural spaces).Conclusion: These neuroanatomical observations in a rat model are consistent with the transport of elemental uranium in different physico-chemical forms (solubilized, nanoparticles) along olfactory nerve bundles after inhalation of UO4 microparticles. This work contributes to knowledge of the mechanistic actions of particulate pollutants on the brain.

Published
2019
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5. Design of model tokamak particles for future toxicity studies: Morphology and physical characterization

Author

Sarah Dine, I. Georges, F. Jambon, J. Chêne, Christian Grisolia, S. Garcia-Argote, Bernard Rousseau, Jérôme Rose, T. Acsente, Chiara Uboldi, G. Dine, M. Sanles Sobrido, Grégory Pieters, Véronique Malard, François Gensdarmes, Etienne Hodille, E. Bernard, Thierry Orsière, P. Beaunier, Dominique Vrel, Nathalie Herlin-Boime, Samuel Peillon, F. Miserque, Ph. Delaporte, Gheorghe Dinescu, Service de Chimie Bio-Organique et de Marquage (SCBM), Médicaments et Technologies pour la Santé (MTS), Université Paris-Saclay-Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Paris-Saclay-Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), 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), Laboratoire Edifices Nanométriques (LEDNA), 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-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), Laboratoire de Réactivité des Surfaces et des Interfaces (LRSI), Département de Physico-Chimie (DPC), CEA-Direction des Energies (ex-Direction de l'Energie Nucléaire) (CEA-DES (ex-DEN)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-CEA-Direction des Energies (ex-Direction de l'Energie Nucléaire) (CEA-DES (ex-DEN)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Laboratoire de Réactivité de Surface (LRS), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Ingénierie des Matériaux et des Hautes Pressions (LIMHP), Université Paris 13 (UP13)-Institut Galilée-Centre National de la Recherche Scientifique (CNRS), Laboratoire des Sciences des Procédés et des Matériaux (LSPM), Université Paris 13 (UP13)-Institut Galilée-Université Sorbonne Paris Cité (USPC)-Centre National de la Recherche Scientifique (CNRS), Institut de Recherche sur la Fusion par confinement Magnétique (IRFM), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Institut de Radioprotection et de Sûreté Nucléaire (IRSN), National Institute for Lasers, Plasma, and Radiation Physics - INFLPR (ROMANIA), Institut méditerranéen de biodiversité et d'écologie marine et continentale (IMBE), Avignon Université (AU)-Aix Marseille Université (AMU)-Institut de recherche pour le développement [IRD] : UMR237-Centre National de la Recherche Scientifique (CNRS), Institut de Biosciences et Biotechnologies d'Aix-Marseille (ex-IBEB) (BIAM), Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS)-Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Ecole Centrale Paris, Laboratoire Lasers, Plasmas et Procédés photoniques (LP3), Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS), A*MIDEX project - 'Investissements d'Avenir' French Government programFrench National Research Agency (ANR) [ANR-11-IDEX-0001-02], Toxicology Program of the French Alternative Energies and Atomic Energy Commission (CEA) through the TWEET project, CNRSCentre National de la Recherche Scientifique (CNRS), CEAFrench Atomic Energy Commission, Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Direction de Recherche Fondamentale (CEA) (DRF (CEA)), 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), 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 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), CEA-Direction de l'Energie Nucléaire (CEA-DEN), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-CEA-Direction de l'Energie Nucléaire (CEA-DEN), Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS)-Université Sorbonne Paris Cité (USPC)-Institut Galilée-Université Paris 13 (UP13), Laboratoire Analyse et Modélisation pour la Biologie et l'Environnement (LAMBE - UMR 8587), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Cergy Pontoise (UCP), Université Paris-Seine-Université Paris-Seine-Université d'Évry-Val-d'Essonne (UEVE)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS)-Institut de recherche pour le développement [IRD] : UMR237-Aix Marseille Université (AMU)-Avignon Université (AU), Centre National de la Recherche Scientifique (CNRS)-Aix Marseille Université (AMU), 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), 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), Centre National de la Recherche Scientifique (CNRS)-Institut Galilée-Université Paris 13 (UP13), Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC), Centre National de la Recherche Scientifique (CNRS)-Université Paris-Saclay-Université d'Évry-Val-d'Essonne (UEVE)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Cergy Pontoise (UCP), Université Paris-Seine-Université Paris-Seine, Centre National de la Recherche Scientifique (CNRS)-Institut Rayonnement Matière de Saclay (IRAMIS), and 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

Subjects
Dusty plasma, Tokamak, Materials science, tungsten, Nuclear engineering, chemistry.chemical_element, Tungsten, fusion technology, 01 natural sciences, size, 010305 fluids & plasmas, law.invention, [SPI.MAT]Engineering Sciences [physics]/Materials, law, Sputtering, 0103 physical sciences, Nuclear fusion, General Materials Science, 010306 general physics, Civil and Structural Engineering, Mechanical Engineering, tungsten nano-particles, Fusion power, Characterization (materials science), Nuclear Energy and Engineering, chemistry, dust, oxide, Beryllium
Abstract

International audience; During ITER operation, it is expected that the large panel of plasma-wall interactions triggers the production of dust particles from the tungsten and beryllium first wall. These particles can be loaded with tritium (T) used as a fuel for the fusion reaction; T inventory is of prime importance for the safety assessment, particularly when considering dispersible matters that could be released in case of a Loss Of Vacuum Accident (LOVA),. The impact of accidental inhalation of such particles has therefore to be evaluated. Yet, particles properties in terms of tritium inventory and general behaviour are strongly dependent on their physical and chemical characteristics, and large uncertainties remain on those parameters; It is therefore important to obtain and characterize relevant W dust samples for toxicity studies before ITER operation starts. We produced model tungsten (W) Nano-Particles (NPs) by two different methods with characteristics closer to the plasma-wall interaction processes than grinding (usually used to produce commercial NPs): (i) magnetron plasma sputtering followed by gas condensation as well as (ii) laser ablation. The two types of tungsten NPs obtained exhibit very different properties investigated by a large characterization techniques panel; but both sets show similarities with samples collected in tokamak or observed in dusty plasmas setups, therefore could potentially be expected in ITER. Producing samples with strong differences is an asset to lead a first global study, highlighting which parameters are key, whether it affects the tritium inventory or the toxicity for lung cells during in vitro studies. In a second phase, it will help precise the impact of ITER particles when their definition will clarify. The aim of this paper is therefore to study and describe the characteristics of different types of W dusts, this knowledge being mandatory for the next steps of the project dealing with tritium inventory in the described W dusts and their suspension in various liquid media for cell exposure for toxicity studies.

Published
2019
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6. Current investigations on tritiated dust and their impact on tokamak safety

Author

T. Acsente, S. Garcia-Argote, C. Decanis, Sophie Feuillastre, I. George, Thierry Orsière, Véronique Malard, Bernard Rousseau, Gheorghe Dinescu, M. Sanles Sobrido, A. Autricque, Jérôme Rose, O. Carvalho, D. Lambertin, E. Bernard, François Gensdarmes, Christian Grisolia, Chiara Uboldi, Laurence Lebaron-Jacobs, Grégory Pieters, Gregoire Dougniaux, Dominique Vrel, Samuel Peillon, K. Liger, Institut de Recherche sur la Fusion par confinement Magnétique (IRFM), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Institut de Radioprotection et de Sûreté Nucléaire (IRSN), Institut Pluridisciplinaire Hubert Curien (IPHC), Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Service de Chimie Bio-Organique et de Marquage (SCBM), Médicaments et Technologies pour la Santé (MTS), Université Paris-Saclay-Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Paris-Saclay-Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Institut de Chimie et Biochimie Moléculaires et Supramoléculaires (ICBMS), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-École Supérieure de Chimie Physique Électronique de Lyon (CPE)-Institut National des Sciences Appliquées de Lyon (INSA Lyon), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Institut de Biosciences et Biotechnologies d'Aix-Marseille (ex-IBEB) (BIAM), Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS)-Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Institut méditerranéen de biodiversité et d'écologie marine et continentale (IMBE), Avignon Université (AU)-Aix Marseille Université (AMU)-Institut de recherche pour le développement [IRD] : UMR237-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), Laboratoire d'Etudes du Comportement à Long Terme des matériaux de conditionnement (LCLT), Département de recherche sur les Procédés et Matériaux pour les Environnements complexes (DPME), CEA-Direction des Energies (ex-Direction de l'Energie Nucléaire) (CEA-DES (ex-DEN)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-CEA-Direction des Energies (ex-Direction de l'Energie Nucléaire) (CEA-DES (ex-DEN)), Laboratoire d'Ingénierie des Matériaux et des Hautes Pressions (LIMHP), Université Paris 13 (UP13)-Institut Galilée-Centre National de la Recherche Scientifique (CNRS), CEA Cadarache, Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS), Université de Lyon-Université de Lyon-Institut National des Sciences Appliquées de Lyon (INSA Lyon), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Institut de Chimie du CNRS (INC)-École Supérieure Chimie Physique Électronique de Lyon-Centre National de la Recherche Scientifique (CNRS), Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS), 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), Département de recherche sur les technologies pour l'enrichissement, le démantèlement et les déchets (DE2D), Centre National de la Recherche Scientifique (CNRS)-Institut Galilée-Université Paris 13 (UP13), Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-École Supérieure Chimie Physique Électronique de Lyon-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS)-Institut de recherche pour le développement [IRD] : UMR237-Aix Marseille Université (AMU)-Avignon Université (AU), and 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)

Subjects
Nuclear and High Energy Physics, Materials science, Thermonuclear fusion, Tokamak, tritiated dust, Nuclear engineering, chemistry.chemical_element, Dielectric, Tungsten, 01 natural sciences, Electric charge, 010305 fluids & plasmas, law.invention, law, Specific surface area, 0103 physical sciences, 010306 general physics, ComputingMilieux_MISCELLANEOUS, [PHYS]Physics [physics], adhesion of tritiated dust, tokamak operation and safety, Condensed Matter Physics, chemistry, 13. Climate action, Particle, Tritium
Abstract

International audience; During International Thermonuclear Experimental Reactor operation, due to plasma-wall interaction, particles/dust will be created in sizes ranging from nanometers to tens of microns. The dust properties, especially their ability to be covered by a thin oxide electrostatic insulating layer, and surface topology deeply affect their tritium inventory. Consequently, physico-chemical properties specific to tritiated tungsten particles and consequence on particle behavior in the facility and environment must be carefully assessed. For size-relevant tungsten particles, the measured tritium inventory is similar to 10 GBq g(-1). However, it varies with the particle specific surface area. Due to tritium beta decay and the oxide-insulating layer, dust exhibits a positive electrostatic self-charging. For a 5 mu m particle in diameter with a 10 GBq g(-1) tritium inventory, self-charging rate could lead to 5.5 10(4) elementary electric charges per day. These electrostatic properties could change the adhesion of dust on walls. In the case of a single particle, the adhesion will be reinforced due to image and dielectric forces. However, if the tritiated particle is part of an aggregate, the adhesion remains unknown. Due to the limited free path of the beta emission in material, the tritium inventory carried by airborne particles cannot be measured in real time by conventional continuous radioactive aerosols monitors, and a new measurement strategy is needed for atmospheric surveillance in the workplace and of facility exhaust. Toxicity studies dealing with exposure to untritiated/tritiated tungsten particles of 100 nm have been undertaken. It was shown that these particles are rapidly dissolved in biologic media. Finally, after collection, dust must be confined to avoid its spreading into the environment. Different technical solutions are presented in this paper.

Published
2019
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7. Assessment of exposure to airborne carbon nanotubes by laser-induced breakdown spectroscopy analysis of filter samples

Author

Jean-Baptiste Sirven, S. Pontreau, Audrey Roynette, François Gensdarmes, S. Motellier, François-Xavier Ouf, Michel Tabarant, P. Dewalle, C. Quéré, Simon Clavaguera, V. Fauvet, A. Guiot, L. Golanski, M. Amdaoud, CEA-Direction des Energies (ex-Direction de l'Energie Nucléaire) (CEA-DES (ex-DEN)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), IVEA Solution, Centre Scientifique d'Orsay, Département des Technologies des NanoMatériaux (DTNM), Laboratoire d'Innovation pour les Technologies des Energies Nouvelles et les nanomatériaux (LITEN), Institut National de L'Energie Solaire (INES), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Institut National de L'Energie Solaire (INES), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-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 Physique et de Métrologie des Aérosols (DSU/SERAC/LPMA), Institut de Radioprotection et de Sûreté Nucléaire (IRSN), Service d'études analytiques et de réactivité des surfaces (SEARS), Département de Physico-Chimie (DPC), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-CEA-Direction des Energies (ex-Direction de l'Energie Nucléaire) (CEA-DES (ex-DEN)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Laboratoire de physique et de métrologie des aérosols (IRSN/PSN-RES/SCA/LPMA), Service du Confinement et de l'Aérodispersion des polluants (IRSN/PSN-RES/SCA), Institut de Radioprotection et de Sûreté Nucléaire (IRSN)-Institut de Radioprotection et de Sûreté Nucléaire (IRSN), and This work was part of the GENESIS project (Global Evaluation of Nanocomposites for Emerging Safe Industrial Solutions) supported by OSEO (France)

Subjects
Materials science, exposure assessment, [PHYS.NUCL]Physics [physics]/Nuclear Theory [nucl-th], Orders of magnitude (temperature), chemistry.chemical_element, Nanoparticle, Nanotechnology, 02 engineering and technology, Carbon nanotube, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 01 natural sciences, Analytical Chemistry, law.invention, law, Laser-induced breakdown spectroscopy, Spectroscopy, Exposure assessment, Detection limit, LIBS, carbon nanotubes, 010401 analytical chemistry, filters, 021001 nanoscience & nanotechnology, 0104 chemical sciences, workplace, chemistry, 13. Climate action, Filter (video), 0210 nano-technology, Carbon
Abstract

International audience; Exposure assessment is a key step in the evaluation of the risk induced by the handling of engineered nanomaterials. It is a very complex task, because several properties of nanoparticles are assumed to have an effect on their hazards. For exposure monitoring at the workplace, real-time onsite measurements are commonly implemented to measure the particles size and number density, whereas the sampled material is subsequently analysed by electron microscopy. A complementary approach would consist in doing onsite chemical analysis of the filter samples, in order to routinely monitor a potential chronic exposure. Laser-induced breakdown spectroscopy (LIBS) has distinctive advantages for this purpose. Therefore, this work aims at evaluating the performances of LIBS to assess the exposure to airborne carbon nanotubes (CNTs) at the workplace. As carbon is a ubiquitous element in the environment, our strategy was to target metal impurities in CNTs, aluminum and iron in our case. Then, we proceeded in three steps. First, we optimized the choice of the filter type to get the lowest detection limit for both elements. Secondly, this filter was used to quantitatively measure deposited CNTs. Eventually, we conducted an onsite measurement campaign in an industrial CNT production plant to evaluate the exposure in a real situation. We demonstrated that we could reach a detection limit for CNTs compliant with the current NIOSH recommendation of 1 μg m$^{−3}$, and that the detected CNTs during the onsite campaign in areas accessible to workers were at an extremely low concentration, several orders of magnitude lower than this recommendation.

Published
2017
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8. LOAC: a small aerosol optical counter/sizer for ground-based and balloon measurements of the size distribution and nature of atmospheric particles – Part 2: First results from balloon and unmanned aerial vehicle flights

Author

Rony Akiki, Nicolas Verdier, Jean-Charles Dupont, C. Camy-Peyret, Pavla Dagsson-Waldhauserova, Jean Sciare, Haraldur Ólafsson, Eric Hamonou, Tjarda Roberts, Gwenaël Berthet, François Gensdarmes, Damien Vignelles, Vincent Duverger, Matthew Salter, Matthieu Gobbi, Thierry Tonnelier, Martin Piringer, Jean-Baptiste Renard, Matthieu Jeannot, Paul Zieger, Daniel Daugeron, Thierry Elias, Patrick Charpentier, Thibaut Lurton, Thierry Décamps, Jérôme Giacomoni, Benoit Couté, Jérémy Surcin, Samuel Mesmin, Marc Mallet, Vincent Crenn, François Dulac, Christophe Mazel, Fabrice Jégou, Laboratoire de Physique et Chimie de l'Environnement et de l'Espace (LPC2E), Observatoire des Sciences de l'Univers en région Centre (OSUC), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Centre National d’Études Spatiales [Paris] (CNES), Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] (LSCE), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Chimie Atmosphérique Expérimentale (CAE), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Environnement SA, Centre National d'Études Spatiales [Toulouse] (CNES), Laboratoire d'aérologie (LAERO), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), Service du Confinement et de l'Aérodispersion des polluants (IRSN/PSN-RES/SCA), Institut de Radioprotection et de Sûreté Nucléaire (IRSN), MeteoModem, Ury, MeteoModem, Laboratoire de Météorologie Dynamique (UMR 8539) (LMD), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-École polytechnique (X)-École des Ponts ParisTech (ENPC)-Centre National de la Recherche Scientifique (CNRS)-Département des Géosciences - ENS Paris, École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL), HYGEOS (SARL), Stockholm University, Groupe Aerophile, University of Iceland [Reykjavik], Institut Pierre-Simon-Laplace (IPSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-École polytechnique (X)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), Fly-n-Sense, Mérignac, Fly-n-Sense, Zentralanstalt für Meteorologie und Geodynamik (ZAMG), ANR-10-LABX-0100,VOLTAIRE,Geofluids and Volatil elements – Earth, Atmosphere, Interfaces – Resources and Environment(2010), Laboratoire d'aérologie (LA), Centre National de la Recherche Scientifique (CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Université Fédérale Toulouse Midi-Pyrénées-Centre National d'Études Spatiales [Toulouse] (CNES)-Météo France-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Université Fédérale Toulouse Midi-Pyrénées-Centre National d'Études Spatiales [Toulouse] (CNES)-Météo France-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées, IRSN, PSN-RES, SCA, École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-École normale supérieure - Paris (ENS Paris), Université d’Auvergne/LPC2E, ANR-10-LABX-100-01/10-LABX-0100,VOLTAIRE,Geofluids and Volatil elements – Earth, Atmosphere, Interfaces – Resources and Environment(2010), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Département des Géosciences - ENS Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-École des Ponts ParisTech (ENPC)-École polytechnique (X)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC), and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National d'Études Spatiales [Toulouse] (CNES)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-École polytechnique (X)

Subjects
[SDU.OCEAN]Sciences of the Universe [physics]/Ocean, Atmosphere, [PHYS.PHYS.PHYS-AO-PH]Physics [physics]/Physics [physics]/Atmospheric and Oceanic Physics [physics.ao-ph], Atmospheric Science, 010504 meteorology & atmospheric sciences, Meteorology, lcsh:TA715-787, lcsh:Earthwork. Foundations, Mineral dust, Balloon, 01 natural sciences, lcsh:Environmental engineering, Aerosol, Troposphere, Ground level, Depth sounding, 13. Climate action, ChArMEx, 0103 physical sciences, Environmental science, Particle, lcsh:TA170-171, 010303 astronomy & astrophysics, Particle counter, 0105 earth and related environmental sciences, Remote sensing
Abstract

International audience; In the companion (Part I) paper, we have described and evaluated a new versatile optical particle counter/sizer named LOAC (Light Optical Aerosol Counter), based on scattering measurements at angles of 12 and 60 •. That allows for some typology identification of particles (droplets, carbonaceous, salts, and mineral dust) in addition to size-segregated counting in a large diameter range from 0.2 µm up to possibly more than 100 µm depending on sampling conditions (Renard et al., 2016). Its capabilities overpass those of preceding optical particle counters (OPCs) allowing the characterization of all kind of aerosols from submicronic-sized absorbing carbonaceous particles in polluted air to very coarse particles (> 10–20 µm in diameter) in desert dust plumes or fog and clouds. LOAC's light and compact design allows measurements under all kinds of balloons , on-board unmanned aerial vehicles (UAVs) and at Published by Copernicus Publications on behalf of the European Geosciences Union. 3674 J.-B. Renard et al.: LOAC: a counter/sizer for ground-based and balloon measurements – Part 2 ground level. We illustrate here the first LOAC airborne results obtained from a UAV and a variety of scientific balloons. The UAV was deployed in a peri-urban environment near Bordeaux in France. Balloon operations include (i) tethered balloons deployed in urban environments in Vi-enna (Austria) and Paris (France), (ii) pressurized balloons drifting in the lower troposphere over the western Mediter-ranean (during the Chemistry-Aerosol Mediterranean Experiment – ChArMEx campaigns), (iii) meteorological sounding balloons launched in the western Mediterranean region (ChArMEx) and from Aire-sur-l'Adour in southwestern France (VOLTAIRE-LOAC campaign). More focus is put on measurements performed in the Mediterranean during (ChArMEx) and especially during African dust transport events to illustrate the original capability of balloon-borne LOAC to monitor in situ coarse mineral dust particles. In particular, LOAC has detected unexpected large particles in desert sand plumes.

Published
2016
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9. Aerosol release fraction by concrete scarifying operations and its implications on the dismantling of nuclear facilities

Author

François Gensdarmes, Sébastien Ritoux, C. Motzkus, Cécile Bodiot, Mamadou Sow, and Yohan Leblois

Subjects
Environmental Engineering, Suction, 010504 meteorology & atmospheric sciences, Health, Toxicology and Mutagenesis, Nuclear engineering, Fraction (chemistry), 010501 environmental sciences, 01 natural sciences, Pollution, Mineralogical composition, Aerosol, Nuclear facilities, 13. Climate action, Slab, Environmental Chemistry, Environmental science, Aerodynamic diameter, Waste Management and Disposal, 0105 earth and related environmental sciences
Abstract

The sanitation of concrete structures through dismantling of nuclear buildings is complicated by the radiological threat associated with the airborne release of fine dust. This is the reason why the aerosol release fraction (ARF) associated with mechanical removal of concrete structure containing radioactivity needs to be accurately evaluated to implement efficient radiological survey. We characterize experimentally the ARF resulting from milling operations on a standard concrete slab in a confined experimental chamber using an industrial scarifying machine. Our results reveal a significant production of fine aerosol particles with a mass median aerodynamic diameter close to 4 µm and which mineralogical composition is dominated by calcium and silica compounds. The ARF measured when a vacuum suction device is used to confine the dust production close to the source is on the order of 5×10-4; the maximum ARF estimated when no suction device is used is on the order of 0.5.

Published
2020
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10. Experimental study of aerosol release following liquid leaks of fission products concentrates simulants

Author

Yohan Leblois, Mamadou Sow, François Gensdarmes, PSN-RES/SCA/LPMA, Institut de Radioprotection et de Sûreté Nucléaire (IRSN), Laboratoire Matériaux et Durabilité des constructions (LMDC), Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Université Toulouse III - Paul Sabatier (UT3), and Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées

Subjects
[PHYS]Physics [physics], Nuclear and High Energy Physics, Fission products, Materials science, 020209 energy, Mechanical Engineering, 02 engineering and technology, Mechanics, Particulates, 01 natural sciences, Spent nuclear fuel, 010305 fluids & plasmas, Aerosol, Surface tension, Nuclear Energy and Engineering, 0103 physical sciences, 0202 electrical engineering, electronic engineering, information engineering, General Materials Science, Safety, Risk, Reliability and Quality, Waste Management and Disposal, Dimensionless quantity, Leakage (electronics)
Abstract

International audience; This article presents an experimental study that encompasses a need for nuclear safety on the consequences of a leakage of fission products (FP) concentrates in a failed vessel during spent fuel reprocessing operations. Particulate airborne release fractions (ARFs), as the result of liquid FP simulants impacting a rigid surface, were assessed for two circular leakage geometries of 1 and 2 mm diameter. The detailed analysis of these ARFs which are between 2.7 × 10−5 and 5.2 × 10−5 for the different experimental configurations revealed their dependence on the surface tension and the viscosity of the solutions, as well as on the impacting jet diameter. The study also makes it possible to develop an empirical correlation that links the ARFs with the dimensionless Ohnesorge and Weber numbers in the considered surface tension and viscosity range.

Published
2019
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11. Particle behavior close to the lower wall of a tokamak type geometry during a loss of vacuum accident

Author

F. Feuillebois, Thomas Gelain, François Gensdarmes, Physique et mécanique des milieux hétérogenes (UMR 7636) (PMMH), Ecole Superieure de Physique et de Chimie Industrielles de la Ville de Paris (ESPCI Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université de Paris (UP), PSN-RES/SCA/LPMA, Institut de Radioprotection et de Sûreté Nucléaire (IRSN), and PSN-RES/SCA/LEMAC

Subjects
[PHYS]Physics [physics], Materials science, Tokamak, Toroid, Mechanical Engineering, Flow (psychology), chemistry.chemical_element, Geometry, Tungsten, 01 natural sciences, 010305 fluids & plasmas, law.invention, Aerodynamic force, Nuclear Energy and Engineering, chemistry, law, 0103 physical sciences, Particle, General Materials Science, Shear velocity, Beryllium, 010306 general physics, Civil and Structural Engineering
Abstract

International audience; The behavior of tungsten and beryllium particles close to the wall of a tokamak type geometry (i.e. a toroidal vacuum vessel) during a loss of vacuum accident (LOVA) is explored in this paper.Values of the flow field and temperature of the air surging into the torus were calculated by Computational Fluid Dynamics (CFD) simulations from an initial low pressure of 1000 Pa by Gelain et al., Fusion Engineering and Design, 100:87–99, 2015. A new CFD calculation is performed here for an initial low pressure of 500 Pa. The aerodynamic forces on particles in rarefied flow are derived from the calculated friction velocity and temperature in the lowest wall region. The focus is on spherical particles, but these values of forces are complemented for comparison with an estimate of the force on an elongated particle following Sentman (1961). Typical particles with diameters of 1, 2, 5, 10, 20 μm are considered. The possibility for particles which are detached from the lower wall to be entrained away the wall is explored. A particle may be detached by the flow field provided it escapes the adhesion force with the wall, which occurs only for a rough wall and large particles. It is then entrained away from the lower part of the wall provided its weight is smaller than the aerodynamic force, which occurs even at low pressure for all sizes of studied beryllium particles and only for specific sizes and a pressure above 1500 Pa for tungsten particles. This key influence of particle weight on the particle dynamics in rarefied gas flow is the focus of the paper. As a result, only particles of intermediate diameters may be resuspended and transferred away from the wall during the whole pressurisation sequence of the vessel. Using the data for the initial low pressure of 500 Pa, these particle diameters are 5, 10 μm for tungsten and 5, 10, 20 μm for beryllium.

Published
2020
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12. Dust remobilization from rough planar surfaces in tokamak steady-state plasmas

Author

Samuel Peillon, François Gensdarmes, N. Fedorczak, Mamadou Sow, Christian Grisolia, Olivier Pluchery, A. Autricque, H. Roche, Institut de Recherche sur la Fusion par confinement Magnétique (IRFM), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Institut de Radioprotection et de Sûreté Nucléaire (IRSN), Laboratoire Matériaux et Durabilité des constructions (LMDC), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA), Institut des Nanosciences de Paris (INSP), Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Université Toulouse III - Paul Sabatier (UT3), and Université de Toulouse (UT)

Subjects
010302 applied physics, [PHYS]Physics [physics], Nuclear and High Energy Physics, Materials science, Tokamak, Materials Science (miscellaneous), chemistry.chemical_element, Plasma, Radius, Tungsten, lcsh:TK9001-9401, 01 natural sciences, Molecular physics, 010305 fluids & plasmas, law.invention, Ion, Nuclear Energy and Engineering, chemistry, law, Drag, Physics::Plasma Physics, Electric field, 0103 physical sciences, Surface roughness, lcsh:Nuclear engineering. Atomic power
Abstract

The ability of tungsten (W) dust to be remobilized from rough tokamak plasma-facing surfaces is investigated in this study. Atomic Force Microscopy is used to evaluate the adhesion force distribution between W spheroids of ∼ 1 − 10 µm radius and a rough W substrate. Our results confirm that the Rabinovich model describes reasonably well the mean adhesion force in tokamak-relevant surface roughness regimes. The external (electric and ion drag) forces are estimated as well using a simplified sheath model. The results reveal that micron-size dust can be resuspended by attainable electric fields in tokamak conditions.

Published
2018
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13. Uncertainty propagation using the Monte Carlo method in the measurement of airborne particle size distribution with a scanning mobility particle sizer

Author

Loïc Coquelin, T. Macé, Gilles Fleury, C. Motzkus, François Gensdarmes, Laurent Le Brusquet, Nicolas Fischer, Laboratoire National de Métrologie et d'Essais [Trappes] (LNE ), Laboratoire des signaux et systèmes (L2S), Université Paris-Sud - Paris 11 (UP11)-CentraleSupélec-Centre National de la Recherche Scientifique (CNRS), Institut de Radioprotection et de Sûreté Nucléaire (IRSN), Laboratoire commun de métrologie LNE-CNAM (LCM), Laboratoire National de Métrologie et d'Essais [Trappes] (LNE )-Conservatoire National des Arts et Métiers [CNAM] (CNAM), and HESAM Université (HESAM)-HESAM Université (HESAM)

Subjects
Physics, Propagation of uncertainty, [STAT.AP]Statistics [stat]/Applications [stat.AP], 010504 meteorology & atmospheric sciences, Applied Mathematics, Monte Carlo method, Statistical parameter, Monte-Carlo simulations, 010501 environmental sciences, 01 natural sciences, [INFO.INFO-MO]Computer Science [cs]/Modeling and Simulation, Sizing, Aerosol, Computational physics, SMPS measurement, [INFO.INFO-TS]Computer Science [cs]/Signal and Image Processing, Scanning mobility particle sizer, [MATH.MATH-ST]Mathematics [math]/Statistics [math.ST], Differential mobility analyzer, Uncertainty propagation, Range (statistics), [SDV.SPEE]Life Sciences [q-bio]/Santé publique et épidémiologie, Instrumentation, Engineering (miscellaneous), 0105 earth and related environmental sciences
Abstract

International audience; A scanning mobility particle sizer (SMPS) is a high resolution nanoparticle sizing system that is widely used as the standard method to measure airborne particle size distributions (PSD) in the size range 1 nm–1 μm. This paper addresses the problem to assess the uncertainty associated with PSD when a differential mobility analyzer (DMA) operates under scanning mode. The sources of uncertainty are described and then modeled either through experiments or knowledge extracted from the literature. Special care is brought to model the physics and to account for competing theories. Indeed, it appears that the modeling errors resulting from approximations of the physics can largely affect the final estimate of this indirect measurement, especially for quantities that are not measured during day-to-day experiments. The Monte Carlo method is used to compute the uncertainty associated with PSD. The method is tested against real data sets that are monosize polystyrene latex spheres (PSL) with nominal diameters of 100 nm, 200 nm and 450 nm. The median diameters and associated standard uncertainty of the aerosol particles are estimated as 101.22 nm ± 0.18 nm, 204.39 nm ± 1.71 nm and 443.87 nm ± 1.52 nm with the new approach. Other statistical parameters, such as the mean diameter, the mode and the geometric mean and associated standard uncertainty, are also computed. These results are then compared with the results obtained by SMPS embedded software.

Published
2018
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14. Mobilization of tungsten dust by electric forces and its bearing on tritiated particles in the ITER tokamak

Author

Christian Grisolia, F. Miserque, Sophie Peillon, Mamadou Sow, François Gensdarmes, Institut de Radioprotection et de Sûreté Nucléaire (IRSN), Institut de Recherche sur la Fusion par confinement Magnétique (IRFM), and Commissariat à l'énergie atomique et aux énergies alternatives (CEA)

Subjects
010302 applied physics, [PHYS]Physics [physics], Materials science, Metallurgy, Refractory metals, chemistry.chemical_element, Dielectric, Adhesion, Tungsten, Condensed Matter Physics, equipment and supplies, 01 natural sciences, 010305 fluids & plasmas, Surfaces, Coatings and Films, Electronic, Optical and Magnetic Materials, chemistry, Electrical resistivity and conductivity, Electric field, 0103 physical sciences, Electrical and Electronic Engineering, Composite material, Layer (electronics), Electrical conductor, Biotechnology
Abstract

International audience; Experimental investigations on the electric field strength required to overcome the adhesion forces of micron size tungsten metallic dust as well as silver and aluminum oxide in powdery form deposited on a conductive surface are presented. The results reveal a strong influence of particulate surface properties on the detachment threshold, especially for tungsten particles which exhibit a thin surface oxide layer that screens their electrical conductivity. Such tungsten particles makes possible that electrostatic self-charging occurs when tritiated because of their dielectric properties even if there are deposited on a conductive grounded surface. © 2017 Elsevier B.V.

Published
2017
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15. Ion current density profiles in negative corona gaps versus EHD confinements

Author

François Gensdarmes, D. Maro, A. Bouarouri, Jean-Pascal Borra, N. Jidenko, D. Boulaud, Centre National de la Recherche Scientifique (CNRS), Laboratoire de physique des gaz et des plasmas (LPGP), Université Paris-Sud - Paris 11 (UP11)-Centre National de la Recherche Scientifique (CNRS), Institut de Radioprotection et de Sûreté Nucléaire (IRSN), and Institut de Radioprotection et de SÛreté Nucléaire, IRSNCentre National de la Recherche Scientifique, CNRS

Subjects
010302 applied physics, [PHYS]Physics [physics], Field (physics), Chemistry, Flux, Ion current, Condensed Matter Physics, 01 natural sciences, Corona, 010305 fluids & plasmas, Surfaces, Coatings and Films, Electronic, Optical and Magnetic Materials, Ion, Ion wind, Physics::Plasma Physics, Electric field, 0103 physical sciences, Electrical and Electronic Engineering, Atomic physics, Corona discharge, Biotechnology
Abstract

International audience; This paper deals with the electric and hydrodynamic confinement of negative ions in a point-to-plane corona discharge gap. Radial ion current density profiles have been measured on the earthed planar electrode, drilled in the axis of the point. The experimental setup is first validated by comparison with the Warburg's law without injected gas flow rate. The gas injected in the gap and blown from the discharge gap through the hole located at the centre of the plane affects neither the electric field close to the point nor the subsequent electric wind. However, it leads to the confinement of ions flux towards the central symmetry axis in the low electric field region up to a critical gas velocity, which for no more effect is measurable. Hence, electro hydro-dynamics confinement of ions can be achieved by limiting the outward radial expansion of ions to increase ion current densities on specific locations close to the low field planar electrode. © 2015 Elsevier B.V.

Published
2016
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16. Three-dimensional motion of particles in a shear flow near a rough wall

Author

C. Monier, G. Le Meur, François Gensdarmes, C. Reynaud, Z. Mana, Marc Rabaud, F. Feuillebois, L. Ricciardi, Institut de Radioprotection et de Sûreté Nucléaire (IRSN), Fluides, automatique, systèmes thermiques (FAST), Université Paris-Sud - Paris 11 (UP11)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS), Institut de Radioprotection et de SÛreté Nucléaire, IRSN RE35/12016622, Laboratoire d'Informatique pour la Mécanique et les Sciences de l'Ingénieur (LIMSI), Université Paris-Sud - Paris 11 (UP11)-Sorbonne Université - UFR d'Ingénierie (UFR 919), Sorbonne Université (SU)-Sorbonne Université (SU)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Université Paris Saclay (COmUE), Laboratoire de physique et de métrologie des aérosols (IRSN/PSN-RES/SCA/LPMA), Service du Confinement et de l'Aérodispersion des polluants (IRSN/PSN-RES/SCA), Institut de Radioprotection et de Sûreté Nucléaire (IRSN)-Institut de Radioprotection et de Sûreté Nucléaire (IRSN), Service de la Pêche, Service d'ophtalmologie [Nantes], Hôtel-Dieu, Actalia [Saint-Lô], and Institut de Radioprotection et de SÃreté Nucléaire, IRSN RE35/12016622

Subjects
Fluid Flow and Transfer Processes, [PHYS]Physics [physics], Atmospheric Science, Environmental Engineering, 010504 meteorology & atmospheric sciences, Chemistry, Mechanical Engineering, Mechanics, Aerodynamics, Radius, Surface finish, Stokes flow, 01 natural sciences, Pollution, Law of the wall, 010305 fluids & plasmas, Aerodynamic force, Physics::Fluid Dynamics, 0103 physical sciences, Particle, Shear flow, 0105 earth and related environmental sciences
Abstract

Corrigendum to “Three-dimensional motion of particles in a shear flow near a rough wall” (Three-dimensional motion of particles in a shear flow near a rough wall (2016) 96 (69–95), (S0021850215001664), (10.1016/j.jaerosci.2015.10.004)); International audience; A model is proposed for the three-dimensional motion of a small spherical particle entrained by the shear flow of a gas near a rough wall. On the basis of experimental results, the wall is modeled by an average small roughness and some much larger isolated peaks, which are yet smaller than the sphere radius. When encountering a high peak of roughness, the particle may be lifted if the aerodynamic force and torque take over the force and torque due to adhesion on the wall. The aerodynamics is treated using previous analytical results for the creeping flow around a particle near a wall. Values of the adhesion forces of a particle near a rough wall are obtained experimentally. When lifted from the wall, the particle follows a three-dimensional trajectory while rotating around the peak of roughness. Examples of calculated trajectories show that the particle may or may not reach the top of the peak, depending on the various physical parameters. Since the velocity of the particle when leaving the peak grows with its final distance from the wall, that velocity is essential for the subsequent particle resuspension by the ambient shear flow. © 2015 Elsevier Ltd.

Published
2016
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17. Performance Assessment of Probes Dedicated to the Monitoring of Surface Particle Contamination

Author

Francoise Sommer, Isabelle Tovena Pecault, Guillaume Basso, François Gensdarmes, Laboratoire de Physique et de Métrologie des Aérosols (DSU/SERAC/LPMA), and Institut de Radioprotection et de Sûreté Nucléaire (IRSN)

Subjects
[PHYS]Physics [physics], Materials science, 010504 meteorology & atmospheric sciences, Opacity, Airflow, Counting efficiency, Analytical chemistry, chemistry.chemical_element, 02 engineering and technology, General Chemistry, 021001 nanoscience & nanotechnology, Condensed Matter Physics, 01 natural sciences, chemistry, Cleanroom, Aluminium, Microscopy, Particle, General Materials Science, Composite material, 0210 nano-technology, Particle counter, 0105 earth and related environmental sciences
Abstract

International audience; Surface probes, based on airflow particle detachment coupled with optical particle counter, are actually available to measure the particle cleanliness of surfaces in cleanroom. No reliable data exits dealing with the performance assessment of these probes in unstuck and counting particles deposited on surfaces. This work presents a method for determining the efficiency of instruments dedicated to particle surface cleanliness measurements. The method is based on the realisation of standard particle deposits by sedimentation and analysis of whole of the contaminated surface by microscopy combined with a micrometric displacement bench. The method is used to assess a trial surface probe with 30 μm and 80 μm glass beads deposited on transparent (glass) or opaque (aluminium) surfaces at concentrations ranging from 1 particle·cm-2 to 50 particles·cm -2. The results obtained show that the overall efficiency of the instrument tested is less than 5 %. The detailed analysis of results shows that this low value is mainly due to poor efficiency of sampling and detection of particles in the optical counter. When analysed in terms of particle detachment efficiency, the results agree qualitatively with a force balance analysis taking into account the friction by airflow and the distribution of adhesion forces of glass particles to glass substrates or rough aluminium substrates. Such result shows that airflow based surface probes for particle cleanliness measurements should be systematically qualified for representative conditions of operations whereas analytical microscopy measurements could be considered as reference. Copyright © 2012 WILEY-VCH Verlag GmbH andamp; Co. KGaA, Weinheim.

Published
2012
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18. Parameter study of microdroplet formation by impact of millimetre-size droplets onto a liquid film

Author

Evelyne Gehin, C. Motzkus, François Gensdarmes, Institut de Radioprotection et de Sûreté Nucléaire (IRSN), Centre d'Etudes et Recherches en Thermique, Environnement et Systèmes [Créteil] (CERTES EA 3481), and Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12)

Subjects
model validation, Atmospheric Science, Work (thermodynamics), 010504 meteorology & atmospheric sciences, aerosol, Parameter studies, microbubble, 01 natural sciences, 010305 fluids & plasmas, Physics::Fluid Dynamics, Surface tension, Viscosity, Droplet impact, size distribution, laboratory method, airborne particle, Composite material, database, Liquid properties, [PHYS]Physics [physics], Fluid Flow and Transfer Processes, Range (particle radiation), Chemistry, article, particle size, parameterization, physical parameters, Pollution, Impact, priority journal, Drops, Experimental investigations, velocity, Environmental Engineering, Bubble, film, experimental study, Optics, nuclear physics, surface tension, 0103 physical sciences, liquid, 0105 earth and related environmental sciences, Aerosols, Of liquid films, formation mechanism, business.industry, bubble, Mechanical Engineering, thickness, Aerosol, Nuclear application, Liquid films, Particle, Millimeter, business, Liquefied gases
Abstract

The objective of this work is to carry out an experimental investigation on the influence of different parameters such as liquid properties (viscosity and liquid-gas surface tension), impacting droplet properties (velocity vi and diameter di) and the thickness of liquid film on the emission of airborne particles produced by the impact of millimetre-size droplets onto a liquid film. Our results show that in the variation range studied, the increase of vi and di or the decrease in liquid film thickness produces an increase in the mean number of microdroplets emitted by impact in the size range 2-50 μm. Furthermore, it was also observed that an increase in viscosity involves a steep decrease in the mean number of microdroplets emitted. These microdroplets may be produced by the fingers pinching of the crown formed during impact. In the case of low surface tension liquid, the formation of bubbles involves high production of droplets smaller than 15 μm. The results presented here constitute a database of the micro-droplets produced to validate models of droplet impact outcomes. © 2009 Elsevier Ltd. All rights reserved.

Published
2009
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19. LOAC: a small aerosol optical counter/sizer for ground-based and balloon measurements of the size distribution and nature of atmospheric particles – Part 1: Principle of measurements and instrument evaluation

Author

Tjarda Roberts, Fabrice Jégou, Matthew Salter, Eric Hamonou, Jérémy Surcin, Matthieu Gobbi, Matthieu Jeannot, Samuel Mesmin, Marc Mallet, Daniel Daugeron, François Gensdarmes, Thierry Décamps, Gwenaël Berthet, Thierry Tonnelier, Jérôme Giacomoni, Vincent Crenn, Benoit Couté, Nicolas Verdier, Paul Zieger, Jean-Baptiste Renard, Damien Vignelles, Vincent Duverger, François Dulac, Thierry Elias, Rony Akiki, Jean-Charles Dupont, Claude Camy-Peyret, Pavla Dagsson-Waldhauserova, Christophe Mazel, Haraldur Ólafsson, Jean Sciare, Martin Piringer, Patrick Charpentier, Thibaut Lurton, Laboratoire de Physique et Chimie de l'Environnement et de l'Espace (LPC2E), Observatoire des Sciences de l'Univers en région Centre (OSUC), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Centre National d’Études Spatiales [Paris] (CNES), Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] (LSCE), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Chimie Atmosphérique Expérimentale (CAE), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Environnement SA, Groupe Aerophile, Centre National d'Études Spatiales [Toulouse] (CNES), Laboratoire d'aérologie (LAERO), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), Service du Confinement et de l'Aérodispersion des polluants (IRSN/PSN-RES/SCA), Institut de Radioprotection et de Sûreté Nucléaire (IRSN), MeteoModem, Ury, MeteoModem, Laboratoire de Météorologie Dynamique (UMR 8539) (LMD), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-École polytechnique (X)-École des Ponts ParisTech (ENPC)-Centre National de la Recherche Scientifique (CNRS)-Département des Géosciences - ENS Paris, École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL), HYGEOS (SARL), Stockholm University, University of Bergen (UiB), University of Iceland [Reykjavik], Institut Pierre-Simon-Laplace (IPSL (FR_636)), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-École polytechnique (X)-Centre National d'Études Spatiales [Toulouse] (CNES)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Université Blaise Pascal - Clermont-Ferrand 2 (UBP), Fly-n-Sense, Mérignac, Fly-n-Sense, Zentralanstalt für Meteorologie und Geodynamik (ZAMG), Université d'Auvergne - Clermont-Ferrand I (UdA), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Centre National de la Recherche Scientifique (CNRS)-Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées, IRSN, PSN-RES, SCA, Département des Géosciences - ENS Paris, École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-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 des Ponts ParisTech (ENPC)-École polytechnique (X)-Institut national des sciences de l'Univers (INSU - CNRS)-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 d'Orléans (UO)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Centre National d’Études Spatiales [Paris] (CNES), Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'aérologie (LA), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse III - Paul Sabatier (UT3), École normale supérieure - Paris (ENS Paris)-École normale supérieure - Paris (ENS Paris), University of Bergen (UIB), École normale supérieure - Paris (ENS Paris)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-École polytechnique (X)-Centre National d'Études Spatiales [Toulouse] (CNES)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de physique et chimie de l'environnement et de l'Espace (LPC2E), UMR 7328 CNRS/Université d'Orléans, and Université d'Orléans (UO)

Subjects
Atmospheric Science, Materials science, 010504 meteorology & atmospheric sciences, Particle number, [SDU.STU.ME]Sciences of the Universe [physics]/Earth Sciences/Meteorology, 01 natural sciences, 010309 optics, Troposphere, Optics, 11. Sustainability, 0103 physical sciences, [PHYS.PHYS.PHYS-INS-DET]Physics [physics]/Physics [physics]/Instrumentation and Detectors [physics.ins-det], lcsh:TA170-171, Stratosphere, ComputingMilieux_MISCELLANEOUS, 0105 earth and related environmental sciences, [SDU.OCEAN]Sciences of the Universe [physics]/Ocean, Atmosphere, Range (particle radiation), Scattering, business.industry, lcsh:TA715-787, lcsh:Earthwork. Foundations, Sea spray, Aerosol, lcsh:Environmental engineering, 13. Climate action, ChArMEx, Particle, business
Abstract

The study of aerosols in the troposphere and in the stratosphere is of major importance both for climate and air quality studies. Among the numerous instruments available, optical aerosol particles counters (OPCs) provide the size distribution in diameter range from about 100 nm to a few tens of µm. Most of them are very sensitive to the nature of aerosols, and this can result in significant biases in the retrieved size distribution. We describe here a new versatile optical particle/sizer counter named LOAC (Light Optical Aerosol Counter), which is light and compact enough to perform measurements not only at the surface but under all kinds of balloons in the troposphere and in the stratosphere. LOAC is an original OPC performing observations at two scattering angles. The first one is around 12°, and is almost insensitive to the refractive index of the particles; the second one is around 60° and is strongly sensitive to the refractive index of the particles. By combining measurement at the two angles, it is possible to retrieve the size distribution between 0.2 and 100 µm and to estimate the nature of the dominant particles (droplets, carbonaceous, salts and mineral particles) when the aerosol is relatively homogeneous. This typology is based on calibration charts obtained in the laboratory. The uncertainty for total concentrations measurements is ±20 % when concentrations are higher than 1 particle cm−3 (for a 10 min integration time). For lower concentrations, the uncertainty is up to about ±60 % for concentrations smaller than 10−2 particle cm−3. Also, the uncertainties in size calibration are ±0.025 µm for particles smaller than 0.6 µm, 5 % for particles in the 0.7–2 µm range, and 10 % for particles greater than 2 µm. The measurement accuracy of submicronic particles could be reduced in a strongly turbid case when concentration of particles > 3 µm exceeds a few particles cm−3. Several campaigns of cross-comparison of LOAC with other particle counting instruments and remote sensing photometers have been conducted to validate both the size distribution derived by LOAC and the retrieved particle number density. The typology of the aerosols has been validated in well-defined conditions including urban pollution, desert dust episodes, sea spray, fog, and cloud. Comparison with reference aerosol mass monitoring instruments also shows that the LOAC measurements can be successfully converted to mass concentrations.

Published
2016
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20. Tritium absorption and desorption in ITER relevant materials comparative study of tungsten dust and massive samples

Author

Frantz Martin, Etienne Hodille, S. Garcia-Argote, F. Miserque, M. Redolfi, Sophie Peillon, Abdelouahab El-Kharbachi, B. Pégourié, François Gensdarmes, T. Acsente, Loïc Marchetti, Dominique Vrel, Véronique Malard, Gheorghe Dinescu, Bernard Rousseau, J. Chêne, Christian Grisolia, Grégory Pieters, Institut de Recherche sur la Fusion par confinement Magnétique (IRFM), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Service de Chimie Bio-Organique et de Marquage (SCBM), Médicaments et Technologies pour la Santé (MTS), Université Paris-Saclay-Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Paris-Saclay-Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Laboratoire des Sciences des Procédés et des Matériaux (LSPM), Université Paris 13 (UP13)-Institut Galilée-Université Sorbonne Paris Cité (USPC)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Biochimie des Systèmes Perturbés (LBSP), Service du Confinement et de l'Aérodispersion des polluants (IRSN/PSN-RES/SCA), Institut de Radioprotection et de Sûreté Nucléaire (IRSN), Centre National de la Recherche Scientifique (CNRS)-Université Sorbonne Paris Cité (USPC)-Institut Galilée-Université Paris 13 (UP13), and IRSN, PSN-RES, SCA

Subjects
[PHYS]Physics [physics], Nuclear and High Energy Physics, Materials science, Radiochemistry, Metallurgy, Refractory metals, chemistry.chemical_element, Sorption, 02 engineering and technology, Plasma, Tungsten, 021001 nanoscience & nanotechnology, 01 natural sciences, 010305 fluids & plasmas, Adsorption, Nuclear Energy and Engineering, chemistry, Desorption, 0103 physical sciences, General Materials Science, Tritium, Absorption (chemistry), 0210 nano-technology
Abstract

International audience; Abstract Tritium adsorption and desorption from well characterized tungsten dust are presented. The dust used are of different types prepared by planetary milling and by aggregation technique in plasma. For the milled powder, the surface specific area (SSA) is 15.5 m2/g. The particles are poly-disperse with a maximum size of 200 nm for the milled powder and 100 nm for the aggregation one. Prior to tritiation the particles are carefully de-oxidized. Both samples are experiencing a high tritium inventory from 5 GBq/g to 35 GBq/g. From comparison with massive samples and considering that tritium inventory increases with SSA, it is shown that surface effects are predominant in the tritium trapping process. Extrapolation to the ITER environment is undertaken with the help of a Macroscopic Rate Equation model. It is shown that, during the life time of ITER, these particles can exceed rapidly 1 GBq/g. © 2014 Elsevier B.V.

Published
2015
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21. Resuspension of carbon dust collected in Tore Supra and exposed to turbulent airflow Controlled experiments and comparison with model

Author

François Gensdarmes, A. Roynette, Sophie Peillon, Christian Grisolia, PSN-RES/SCA/LPMA, Institut de Radioprotection et de Sûreté Nucléaire (IRSN), Institut de Recherche sur la Fusion par confinement Magnétique (IRFM), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Laboratoire de physique et de métrologie des aérosols (IRSN/PSN-RES/SCA/LPMA), Service du Confinement et de l'Aérodispersion des polluants (IRSN/PSN-RES/SCA), and Institut de Radioprotection et de Sûreté Nucléaire (IRSN)-Institut de Radioprotection et de Sûreté Nucléaire (IRSN)

Subjects
Materials science, Tokamak, Meteorology, Turbulent airflow, Carbon dust, chemistry.chemical_element, Tore Supra, 01 natural sciences, 010305 fluids & plasmas, law.invention, law, 0103 physical sciences, General Materials Science, 010306 general physics, education, Civil and Structural Engineering, Wind tunnel, [PHYS]Physics [physics], education.field_of_study, Mechanical Engineering, Mechanics, Nuclear Energy and Engineering, chemistry, Particle-size distribution, Particle size, Carbon
Abstract

International audience; This work presents the results of experiments conducted with carbon microparticles collected in the tokamak Tore Supra in order to characterize their resuspension behaviour from a stainless-steel substrate when exposed to turbulent airflow. Experiments were conducted in a wind tunnel with controlled velocity profiles and monitored environmental conditions. A consequent amount of dust has been collected in the vessel of the tokamak and a bimodal particle size distribution of samples is first demonstrated. Comparison with resuspension of alumina powders with equivalent particle size distributions under turbulent airflow is also discussed. Results for both carbon and alumina microparticles are then compared to a theoretical resuspension model. Data reveal that exposing multilayer deposits with bimodal particle size distributions to low-speed flows (i.e. 3-10 m/s) induces a significant reduction of the mobilized fractions compared to what was predicted by the model. In addition, results helped to highlight some limitations in the model to physically describe changes in the adhesive strength that can occur with a polydisperse deposit. © 2014 Published by Elsevier B.V.

Published
2014
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22. Determining the count median diameter of nanoaerosols by simultaneously measuring their number and lung deposited surface area concentrations

Author

Dominique Thomas, Olivier Witschger, Sébastien Bau, François Gensdarmes, Laboratoire de Métrologie des Aérosols, Département Métrologie des Polluants (MP), Institut national de recherche et de sécurité (Vandoeuvre lès Nancy) (INRS ( Vandoeuvre lès Nancy))-Institut national de recherche et de sécurité (Vandoeuvre lès Nancy) (INRS ( Vandoeuvre lès Nancy)), Institut de Radioprotection et de Sûreté Nucléaire (IRSN), Laboratoire Réactions et Génie des Procédés (LRGP), Université de Lorraine (UL)-Centre National de la Recherche Scientifique (CNRS), Institut national de recherche et de sécurité (Vandoeuvre lès Nancy) (INRS ( Vandoeuvre lès Nancy)), and Centre National de la Recherche Scientifique (CNRS)-Université de Lorraine (UL)

Subjects
Nanoaerosol, Materials science, Nanoparticle measurement method, Instrumentation, Analytical chemistry, Bioengineering, 010501 environmental sciences, 01 natural sciences, [CHIM.GENI]Chemical Sciences/Chemical engineering, Mass concentration (chemistry), Geometric standard deviation, General Materials Science, [PHYS.PHYS.PHYS-INS-DET]Physics [physics]/Physics [physics]/Instrumentation and Detectors [physics.ins-det], [SPI.NANO]Engineering Sciences [physics]/Micro and nanotechnologies/Microelectronics, 0105 earth and related environmental sciences, 010405 organic chemistry, Ranging, General Chemistry, Condensed Matter Physics, Atomic and Molecular Physics, and Optics, 0104 chemical sciences, Aerosol, Modeling and Simulation, Log-normal distribution, Lung-deposited surface area concentration, Particle, Particle size, Count median diameter, Biological system
Abstract

International audience; Due to the increasing use of nanomaterials in research and product development, it is probable that the number of situations of occupational exposure to them is also rising. The same is true for the number of workers. Although current research in nanotoxicology is far from conclusive, it is clear that relying on mass concentration and chemical composition alone is not appropriate in all cases and alternative measurement methods and approaches need to be developed. In this work, we propose a method based on simultaneous size-integrated measurements of two particle concentrations (number and lung-deposited surface area, CNC/NSAM), and on the estimation of the average size of potentially inhaled particles from the combination of these measurements. The proposed method could be part of a measurement strategy that is practical as it would use field-portable, commercially available aerosol instruments. In the absence of instruments providing real-time size-resolved measurements, this original approach can be carried out as considering that the ratio of these concentrations is a monotonous function of particle size. Indeed, the latter function depends only on the geometric standard deviation of airborne particle number size distribution, assumed to be lognormal. Compared to SMPS data for polydisperse aerosols having three chemical natures with count median diameters ranging from 64 to 177 nm, experimental results were obtained with acceptable relative discrepancies of ±30 %. Though the method proposed is less accurate than traditional instruments like SMPS, it can be used for workplace air monitoring or as a screening tool to detect the presence of airborne nanoparticles

Published
2013
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23. Size characterization of airborne SiO2 nanoparticles with on-line and off-line measurement techniques: an interlaboratory comparison study

Author

Sebastien Ducourtieux, Sylvain Bondiguel, Loukie Adlem, François Gensdarmes, François Gaie-Levrel, C.S. Kim, Graham R. Johnson, Thor E. Bostrom, Lidia Morawska, A. Salas, Vasile-Dan Hodoroaba, Young Heon Kim, Camilla Costa, Keiji Takahata, Kai Dirscherl, J.A. Guardado, T. Macé, C. Motzkus, Alexandra Delvallée, Åsa K. Jämting, Patrick Ausset, O. Popov, M.C. Chu, Ehsan Majd Faghihi, Ilya Kuselman, Inna Popov, S. Vaslin-Reimann, Gustavo Capannelli, Kensei Ehara, M. Maille, Malcolm Lawn, N. Michielsen, National Metrology Institute of South Africa, Laboratoire National de Métrologie et d’Essais (LNE), Danish Institute of Fundamental Metrology, BAM Federal Institute for Materials Research and Testing, Federal Institute for Materials Research and Testing - Bundesanstalt für Materialforschung und -prüfung (BAM), The Hebrew University of Jerusalem (HUJ), National Metrology Institute of Japan, National Institute od Advanced Industrial Science and Technology, Laboratoire Interuniversitaire des Systèmes Atmosphériques (LISA (UMR_7583)), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité), Laboratoire de Physique et de Métrologie des Aérosols (IRSN/DSU/SERAC/LPMA), Institut de Radioprotection et de Sûreté Nucléaire (IRSN), International Laboratory for Air Quality and Health [Brisbane], Queensland University of Technology [Brisbane] (QUT), Korea Research Institute of Standards and Science [Daejon] (KRISS), KRISS, Department of Chemistry and Industrial Chemistry, Genova University, Università degli studi di Genova = University of Genoa (UniGe), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12)-Centre National de la Recherche Scientifique (CNRS)-Université de Paris (UP), Laboratoire de Physique et de Métrologie des Aérosols (DSU/SERAC/LPMA), and Universita degli studi di Genova

Subjects
010504 meteorology & atmospheric sciences, aerosol, Analytical chemistry, Nanoparticle, 02 engineering and technology, 01 natural sciences, Characterization measurement, Atomic force microscopy, Mica, electrostatic precipitation, General Materials Science, [PHYS]Physics [physics], silicon dioxide, education.field_of_study, Electrostatic separators, evaluation, Spectrometers, nanoparticle, article, Particle size, 021001 nanoscience & nanotechnology, Condensed Matter Physics, Atomic and Molecular Physics, and Optics, unclassified drug, Metrology, Characterization (materials science), Interlaboratory comparison studies, priority journal, Modeling and Simulation, Uncertainty analysis, Measurement uncertainty, Nanoparticles characterizations, 0210 nano-technology, Scanning mobility, Scanning electron microscopy, Scanning and transmission electron microscopy, Materials science, Characterization, Population, Bioengineering, Shape memory effect, Interlaboratory comparison, transmission electron microscopy, Calibration, controlled study, education, 0105 earth and related environmental sciences, Aerosols, Spectrometer, silicon dioxide nanoparticle, Size distribution, General Chemistry, calibration, scanning mobility particle size spectrometer, Nanoparticles, measurement, spectrometer, Metrological traceabilitys
Abstract

Results of an interlaboratory comparison on size characterization of SiO2 airborne nanoparticles using on-line and off-line measurement techniques are discussed. This study was performed in the framework of Technical Working Area (TWA) 34 - "Properties of Nanoparticle Populations" of the Versailles Project on Advanced Materials and Standards (VAMAS) in the project no. 3 "Techniques for characterizing size distribution of airborne nanoparticles". Two types of nano-aerosols, consisting of (1) one population of nanoparticles with a mean diameter between 30.3 and 39.0 nm and (2) two populations of non-agglomerated nanoparticles with mean diameters between, respectively, 36.2-46.6 nm and 80.2-89.8 nm, were generated for characterization measurements. Scanning mobility particle size spectrometers (SMPS) were used for on-line measurements of size distributions of the produced nano-aerosols. Transmission electron microscopy, scanning electron microscopy, and atomic force microscopy were used as off-line measurement techniques for nanoparticles characterization. Samples were deposited on appropriate supports such as grids, filters, and mica plates by electrostatic precipitation and a filtration technique using SMPS controlled generation upstream. The results of the main size distribution parameters (mean and mode diameters), obtained from several laboratories, were compared based on metrological approaches including metrological traceability, calibration, and evaluation of the measurement uncertainty. Internationally harmonized measurement procedures for airborne SiO2 nanoparticles characterization are proposed. © 2013 Springer Science+Business Media Dordrecht.

Published
2013
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24. Size distributions of airborne radionuclides from the fukushima nuclear accident at several places in europe

Author

Olivier Meisenberg, Magdalena Długosz-Lisiecka, W. Ringer, Petr Rulík, Konstantinos Eleftheriadis, Olivier Masson, Helena Malá, Anne de Vismes-Ott, François Gensdarmes, Laboratoire d'étude radioécologique du milieu continental et marin (LERCM), Institut de Radioprotection et de Sûreté Nucléaire (IRSN)-Direction de l'Environnement et de l'Intervention, Austrian Agency for Health and Food Safety (AGES), National Radiation Protection Institute (NRPI/SURO), Institute of Applied Radiation Chemistry, Łódź University of Technology, Environmental Radioactivity laboratory (ERL), Institute of Nuclear and Radiological Sciences and Technology, Energy and Safety (INRASTES), National Center for Scientific Research 'Demokritos' (NCSR)-National Center for Scientific Research 'Demokritos' (NCSR), PRP-ENV/STEME/LMRE, Laboratoire de Mesure de la Radioactivité dans l’Environnement, Institut de Radioprotection et de Sûreté Nucléaire (IRSN), and Laboratoire de Physique et de Métrologie des Aérosols (DSU/SERAC/LPMA)

Subjects
010504 meteorology & atmospheric sciences, Cesium Isotopes, Fukushima Nuclear Accident, [SDV]Life Sciences [q-bio], chemistry.chemical_element, 010501 environmental sciences, Atmospheric sciences, 01 natural sciences, 7. Clean energy, Iodine Radioisotopes, Radiation Monitoring, Environmental Chemistry, Geometric standard deviation, Particle Size, 0105 earth and related environmental sciences, Anthropogenic radionuclides, Radionuclide, Environmental engineering, General Chemistry, Aerosol, Europe, chemistry, 13. Climate action, Air Pollutants, Radioactive, Cesium Radioisotopes, Caesium, Environmental science, Particle size
Abstract

International audience; Segregation and radioactive analysis of aerosols according to their aerodynamic size were performed in France, Austria, the Czech Republic, Poland, Germany, and Greece after the arrival of contaminated air masses following the nuclear accident at the Fukushima Dai-ichi nuclear power plant in March 2011. On the whole and regardless of the location, the highest activity levels correspond either to the finest particle fraction or to the upper size class. Regarding anthropogenic radionuclides, the activity median aerodynamic diameter (AMAD) ranged between 0.25 and 0.71 μm for 137Cs, from 0.17 to 0.69 μm for 134Cs, and from 0.30 to 0.53 μm for 131I, thus in the "accumulation mode" of the ambient aerosol (0.1-1 μm). AMAD obtained for the naturally occurring radionuclides 7Be and 210Pb ranged from 0.20 to 0.53 μm and 0.29 to 0.52 μm, respectively. Regarding spatial variations, AMADs did not show large differences from place to place compared with what was observed concerning bulk airborne levels registered on the European scale. When air masses arrived in Europe, AMADs for 131I were about half those for cesium isotopes. Higher AMAD for cesium probably results from higher AMAD observed at the early stage of the accident in Japan. Lower AMAD for 131I can be explained by the adsorption of gaseous iodine on particles of all sizes met during transport, especially for small particles. Additionally, weathering conditions (rain) encountered during transport and in Europe in March and April contributed to the equilibrium of the gaseous to total 131I ratio. AMAD slightly increased with time for 131I whereas a clear decreasing trend was observed with the AMADs for 137Cs and 134Cs. On average, the associated geometric standard deviation (GSD) appeared to be higher for iodine than for cesium isotopes. These statements also bear out a gaseous 131I transfer on ambient particles of a broad size range during transport. Highest weighted activity levels were found on the 0.49-0.95 μm and on the 0.18-0.36 μm size ranges in France and in Poland, respectively. The contribution from resuspension of old deposited 137Cs was assessed for the coarse particle fractions only for the first sampling week. © 2013 American Chemical Society.

Published
2013
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25. Design and performance of a new device for the study of thermophoresis: The radial flow thermophoretic analyser

Author

François-Xavier Ouf, Edouard Brugière, Jérôme Yon, Alexis Coppalle, François Gensdarmes, Denis Boulaud, Complexe de recherche interprofessionnel en aérothermochimie (CORIA), Université de Rouen Normandie (UNIROUEN), Normandie Université (NU)-Normandie Université (NU)-Institut national des sciences appliquées Rouen Normandie (INSA Rouen Normandie), Institut National des Sciences Appliquées (INSA)-Normandie Université (NU)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS), Institut de Radioprotection et de Sûreté Nucléaire (IRSN), and IRSN / PSN-RES / SCA

Subjects
Fluid Flow and Transfer Processes, [PHYS]Physics [physics], Atmospheric Science, Environmental Engineering, 010504 meteorology & atmospheric sciences, Field (physics), Chemistry, Mechanical Engineering, Analyser, Radial flow analyser Thermophoretic velocity Thermophoresis Transfer function, Repeatability, Mechanics, 010501 environmental sciences, 01 natural sciences, Pollution, Transfer function, Thermophoresis, Temperature gradient, Classical mechanics, New device, Radial flow, ComputingMilieux_MISCELLANEOUS, 0105 earth and related environmental sciences
Abstract

A new device to study the thermophoresis of particles is presented in this paper. The instrument, called a radial flow thermophoretic analyser, is based on the geometry of the radial flow differential mobility analyser RF-DMA or SMEC (Spectrometre de Mobilite Electrique Circulaire). The device uses two circular plates, each with hot and cold temperature imposed. The instrument was designed with computational fluid dynamic software in order to check uniformity of the temperature field in the selection area after an establishment length. The transfer function of the instrument is then established and determines the effective thermophoretic velocity of particles selected in the temperature field imposed in the apparatus. For the experimental validation, effective thermophoretic velocities of monodispersed spherical latex particles for diameters ranging from 64 nm to 500 nm and a temperature gradient equal to 50,750 K/m are measured and compared with theoretical values. The results show good repeatability and discrepancies with theoretical values less than 7%.

Published
2013
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26. Inhalation of uranium nanoparticles: respiratory tract deposition and translocation to secondary target organs in rats

Author

Isabelle Dublineau, Philippe Lestaevel, François Gensdarmes, Benjamin B. Tournier, B. Dhieux, F. Petitot, Sébastien Jacquinot, Patricia Beaunier, Charline Mazzucco, Olivia Delissen, Elie Tourlonias, Laboratoire de radiotoxicologie et radiobiologie expérimentale (IRSN/PRP-HOM/SRBE/LRTOX), Institut de Radioprotection et de Sûreté Nucléaire (IRSN), Service du Confinement et de l'Aérodispersion des polluants (IRSN/PSN-RES/SCA), Laboratoire de Réactivité de Surface (LRS), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Institut de Radioprotection et de Sûreté Nucléaire (IRSN/PRP-HOM/SRBE), Laboratoire de radiotoxicologie expérimentale, Direction de la radioprotection de l'homme, and Institut de Radioprotection et de Sûreté Nucléaire (IRSN/PSN-RES/SCA)

Subjects
Nuclear fuel cycle, inorganic chemicals, Male, Respiratory System/drug effects/metabolism, Respiratory System, Metal Nanoparticles, chemistry.chemical_element, 010501 environmental sciences, Toxicology, 01 natural sciences, complex mixtures, Mass Spectrometry, Statistics, Nonparametric, Rats, Sprague-Dawley, 03 medical and health sciences, Microscopy, Electron, Transmission, Ultrafine particle, Depleted uranium, In vivo, Administration, Inhalation, medicine, Animals, Particle Size, 030304 developmental biology, 0105 earth and related environmental sciences, Inhalation exposure, 0303 health sciences, Inhalation, Chemistry, Radiochemistry, technology, industry, and agriculture, General Medicine, [CHIM.CATA]Chemical Sciences/Catalysis, Uranium, Uranium/pharmacokinetics/toxicity, Rats, Deposition (aerosol physics), medicine.anatomical_structure, Blood, Ultrafine particles, 13. Climate action, Nanoparticles, Rat, Respiratory tract, Metal Nanoparticles/toxicity
Abstract

International audience; Uranium nanoparticles (

Published
2013
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27. Contribution to the study of particle resuspension kinetics during thermal degradation of polymers

Author

Laurent Ferry, François Gensdarmes, S. Delcour, Jérôme Yon, N. Azema, A. Niang, José-Marie Lopez-Cuesta, François-Xavier Ouf, Alexis Coppalle, S. Pontreau, IRSN, PSN-RES, SCA, Institut de Radioprotection et de Sûreté Nucléaire (IRSN), Centre des Matériaux des Mines d'Alès (C2MA), IMT - MINES ALES (IMT - MINES ALES), Institut Mines-Télécom [Paris] (IMT)-Institut Mines-Télécom [Paris] (IMT), Pôle Matériaux et Structures du Génie Civil (Pôle MSGC), Institut Mines-Télécom [Paris] (IMT)-Institut Mines-Télécom [Paris] (IMT)-IMT - MINES ALES (IMT - MINES ALES), Complexe de recherche interprofessionnel en aérothermochimie (CORIA), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences appliquées Rouen Normandie (INSA Rouen Normandie), Institut National des Sciences Appliquées (INSA)-Normandie Université (NU)-Institut National des Sciences Appliquées (INSA)-Normandie Université (NU)-Université de Rouen Normandie (UNIROUEN), Normandie Université (NU), and Pôle Matériaux Polymères Avancés (Pôle MPA)

Subjects
Environmental Engineering, Materials science, Hot Temperature, 010504 meteorology & atmospheric sciences, Polymers, Health, Toxicology and Mutagenesis, Analytical chemistry, 01 natural sciences, 030218 nuclear medicine & medical imaging, 03 medical and health sciences, chemistry.chemical_compound, 0302 clinical medicine, Thermal degradation of polymers, Air Pollution, Aluminum Oxide, Environmental Chemistry, Polymethyl Methacrylate, Polycarbonate, Particle Size, Waste Management and Disposal, ComputingMilieux_MISCELLANEOUS, 0105 earth and related environmental sciences, chemistry.chemical_classification, [PHYS]Physics [physics], Aerosols, Air Pollutants, Polycarboxylate Cement, Airborne release fraction Fire PMMA PC Aluminium oxide, Air, Polymer, Equipment Design, Pollution, Kinetics, chemistry, Heat flux, visual_art, Particle-size distribution, Aluminium oxide, visual_art.visual_art_medium, Particle, Particle size, Environmental Monitoring
Abstract

Experimental results are reported on the resuspension of particles deposited on polymer samples representative of glove boxes used in the nuclear industry, under thermal degradation. A parametric study was carried out on the effects of heat flux, air flow rate, fuel type and particle size distribution. Small-scale experiments were conducted on 10 cm × 10 cm PolyMethyl MethAcrylate (PMMA) and PolyCarbonate (PC) samples covered with aluminium oxide particles with physical geometric diameters of 0.7 and 3.6 μm. It was observed for both polymer (fuel) samples that heat flux has no effect on the airborne release fraction (ARF), whereas particle size is a significant parameter. In the case of the PMMA sample, ARF values for 0.7 and 3.6 μm diameter particles range from 12.2% (± 6.2%) to 2.1% (± 0.6%), respectively, whereas the respective values for the PC sample range from 3.2% (± 0.8%) to 6.9% (± 3.9%). As the particle diameter increases, a significant decrease in particle release is observed for the PMMA sample, whereas an increase is observed for the PC sample. Furthermore, a peak airborne release rate is observed during the first instants of PMMA exposure to thermal stress. An empirical relationship has been proposed between the duration of this peak release and the external heat flux.

Published
2012
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28. Aerosol size distribution measurement using a SMPS: scanning mode and uncertainty analysis

Author

Nicolas Fischer, Gilles Fleury, L. Le Brusquet, C. Motzkus, François Gensdarmes, Loïc Coquelin, Laboratoire commun de métrologie LNE-CNAM (LCM), Laboratoire National de Métrologie et d'Essais [Trappes] (LNE )-Conservatoire National des Arts et Métiers [CNAM] (CNAM), Supélec Sciences des Systèmes (E3S), Ecole Supérieure d'Electricité - SUPELEC (FRANCE), and Institut de Radioprotection et de Sûreté Nucléaire (IRSN)

Subjects
Physics, [STAT.AP]Statistics [stat]/Applications [stat.AP], 010504 meteorology & atmospheric sciences, Analyser, Monte Carlo method, 010501 environmental sciences, 01 natural sciences, [INFO.INFO-MO]Computer Science [cs]/Modeling and Simulation, Computational physics, Aerosol, [INFO.INFO-TS]Computer Science [cs]/Signal and Image Processing, Scanning mobility particle sizer, Global sensitivity analysis, Electronic engineering, Measurement uncertainty, [SPI.SIGNAL]Engineering Sciences [physics]/Signal and Image processing, [STAT.ME]Statistics [stat]/Methodology [stat.ME], Uncertainty analysis, 0105 earth and related environmental sciences, Confidence region
Abstract

International audience; A model to simulate SMPS (Scanning Mobility Particle Sizer) measurement and the associated uncertainty analysis when axial DMA (Di erential Mobility Analyser) classi er operates under scanning mode conditions is de- scribed. Starting from simulated SMPS raw data, a fast estimation of aerosol size distribution measurement using regularization technique is performed. Then, global sensi- tivity analysis is used to discriminate signi cant parameters of the system and, as a preliminary result, a 95% con dence region is obtained by Monte Carlo simulations on an atmo- spheric aerosol size distribution.

Published
2012
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29. Evaluating three direct-reading instruments based on diffusion charging to measure surface area concentrations in polydisperse nanoaerosols in molecular and transition regimes

Author

François Gensdarmes, Olivier Witschger, Sébastien Bau, Dominique Thomas, Institut national de recherche et de sécurité (Vandoeuvre lès Nancy) (INRS ( Vandoeuvre lès Nancy)), Institut de Radioprotection et de Sûreté Nucléaire (IRSN), Laboratoire Réactions et Génie des Procédés (LRGP), and Université de Lorraine (UL)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Surface (mathematics), Materials science, 010504 meteorology & atmospheric sciences, Particle number, Dispersity, Analytical chemistry, Nanoparticle, Bioengineering, General Chemistry, 010501 environmental sciences, Condensed Matter Physics, 01 natural sciences, Measure (mathematics), Electric charge, Atomic and Molecular Physics, and Optics, [CHIM.GENI]Chemical Sciences/Chemical engineering, Chemical physics, Modeling and Simulation, Particle, General Materials Science, [SPI.GPROC]Engineering Sciences [physics]/Chemical and Process Engineering, Diffusion (business), ComputingMilieux_MISCELLANEOUS, 0105 earth and related environmental sciences
Abstract

Many toxicology studies on insoluble and poorly soluble nanoparticles point out surface area as an indicator of inhalation exposure. Measuring this criterion thus constitutes an important challenge. Instruments exist which can measure particle surface area concentration in real-time, but it is not known how well they perform when faced with polydisperse nanostructured aerosols. In this study, the response functions of three commercially available instruments based on diffusion charging (LQ1-DC, Matter Engineering; NSAM, TSI model 3550; AeroTrak™ 9000, TSI) were measured for monodisperse aerosols of four different chemical natures with particles ranging in size from 15 to 520 nm. Our results show good agreement between the experimental and theoretical response functions for the three instruments studied. In addition, no significant effect of the chemical nature, density or particle morphology was revealed. Instrument response was also tested with polydisperse aerosols. For these aerosols, discrepancies were observed between measurements and calculated concentrations based on response function and particle number size distribution. Relative differences varied between −60 and +55 % with an average value of −20 %. These differences may be explained by different factors; among them, the existence of a distribution of electrical charges on particles can lead to identical signals measured, and differential diffusion charging performance might lead to concentration-dependent response.

Published
2012
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30. Study of the coalescence/splash threshold of droplet impact on liquid films and its relevance in assessing airborne particle release

Author

Evelyne Gehin, François Gensdarmes, C. Motzkus, Laboratoire commun de métrologie LNE-CNAM (LCM), Laboratoire National de Métrologie et d'Essais [Trappes] (LNE )-Conservatoire National des Arts et Métiers [CNAM] (CNAM), HESAM Université - Communauté d'universités et d'établissements Hautes écoles Sorbonne Arts et métiers université (HESAM)-HESAM Université - Communauté d'universités et d'établissements Hautes écoles Sorbonne Arts et métiers université (HESAM), Laboratoire National de Métrologie et d’Essais (LNE), Laboratoire de Physique et de Métrologie des Aérosols (IRSN/DSU/SERAC/LPMA), Institut de Radioprotection et de Sûreté Nucléaire (IRSN), Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12), Université Paris-Est (UPE), and Laboratoire de Physique et de Métrologie des Aérosols (DSU/SERAC/LPMA)

Subjects
Work (thermodynamics), Meteorology, Surface Properties, 020209 energy, 02 engineering and technology, 01 natural sciences, Airborne particle, Resuspension, 010305 fluids & plasmas, Prompt splash, Physics::Fluid Dynamics, Biomaterials, Surface tension, Droplet, Viscosity, Colloid and Surface Chemistry, 0103 physical sciences, 0202 electrical engineering, electronic engineering, information engineering, Surface Tension, Particle Size, Aerosol, Coalescence (physics), [PHYS]Physics [physics], Splash, Chemistry, Mechanics, Surfaces, Coatings and Films, Electronic, Optical and Magnetic Materials, 13. Climate action, Particulate Matter, Airborne release fraction, Dimensionless quantity
Abstract

International audience; Impingement of droplets on surfaces occurs in many industrial and natural processes. The study of droplet break-up is fundamental in order to determine the potential sources of airborne contamination for scenarios of hazardous liquid falls such as dripping. There are very few data in the literature describing the case of impact of millimetre-size droplets. The purposes of this work were to study experimentally particle emission during the impact of droplets on a liquid film and to assess the use of coalescence/splash relations to predict airborne particle release. The results are described using dimensionless numbers taking into account the inertial, viscosity and surface tension forces. Experiments were carried out for Weber numbers between 62 and 1754 and for Ohnesorge numbers between 2.0×10 -3 and 1.5×10 -2. New results on coalescence/splash thresholds are obtained using highly sensitive aerosol measurement and allow a prediction concerning the presence or absence of airborne particles according to a threshold relation. Moreover, we propose a modification of the Cossali et al.'s [1] relation in order to describe the coalescence/prompt splash threshold. © 2011 Elsevier Inc.

Published
2011
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31. Electrical properties of airborne nanoparticles produced by a commercial spark-discharge generator

Author

Sébastien Bau, Dominique Thomas, Jean-Pascal Borra, François Gensdarmes, Olivier Witschger, Laboratoire de Métrologie des Aérosols, Département Métrologie des Polluants (MP), Institut national de recherche et de sécurité (Vandoeuvre lès Nancy) (INRS ( Vandoeuvre lès Nancy))-Institut national de recherche et de sécurité (Vandoeuvre lès Nancy) (INRS ( Vandoeuvre lès Nancy)), Laboratoire de Physique et de Métrologie des Aérosols, Institut National de la Recherche Scientifique [Québec] (INRS), Laboratoire Réactions et Génie des Procédés (LRGP), Université de Lorraine (UL)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de physique des gaz et des plasmas (LPGP), and Université Paris-Sud - Paris 11 (UP11)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Spectrum analyzer, Materials science, 010504 meteorology & atmospheric sciences, Analytical chemistry, Nanoparticle, Bioengineering, Nanotechnology, 010501 environmental sciences, 01 natural sciences, Spark discharge, Generator (circuit theory), Synthesis, Mobility analysis, General Materials Science, [SPI.GPROC]Engineering Sciences [physics]/Chemical and Process Engineering, 0105 earth and related environmental sciences, Modeling, General Chemistry, Condensed Matter Physics, Atomic and Molecular Physics, and Optics, Bipolar charging model, Agglomerate, Modeling and Simulation, Electrical properties, Electric discharge
Abstract

International audience; nanoparticle generator based on the principle of electrical discharge (PALAS GFG-1000) was used to produce nanoparticles of different chemical natures. The fractions of electrically neutral particles were then measured by means of a Spectromètre de Mobilité Electrique Circulaire (SMEC, i.e. radial-flow mobility analyzer) for different operating conditions. The experimental results were compared with the theoretical values calculated from the Fuchs extended charge equilibrium model for spherical particles and agglomerates. For the smallest particles (below 20 nm), the deviations observed remain below 10%, and tend towards 20% for larger particles (over 35 nm).

Published
2010
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32. A TEM-based method as an alternative to the BET method for measuring off-line the specific surface area of nanoaerosols

Author

Dominique Thomas, Olivier Witschger, O. Rastoix, François Gensdarmes, Sébastien Bau, Laboratoire de Métrologie des Aérosols, Département Métrologie des Polluants (MP), Institut national de recherche et de sécurité (Vandoeuvre lès Nancy) (INRS ( Vandoeuvre lès Nancy))-Institut national de recherche et de sécurité (Vandoeuvre lès Nancy) (INRS ( Vandoeuvre lès Nancy)), Laboratoire de Physique et de Métrologie des Aérosols, Institut National de la Recherche Scientifique [Québec] (INRS), Laboratoire d'Analyse Inorganique et de Caractérisation des Aérosols (LAICA), Laboratoire Réactions et Génie des Procédés (LRGP), and Université de Lorraine (UL)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Materials science, 010504 meteorology & atmospheric sciences, General Chemical Engineering, Analytical chemistry, Nanoparticle, Mineralogy, Specific surface area, Overlap coefficient, 02 engineering and technology, medicine.disease_cause, 01 natural sciences, Suspension (chemistry), medicine, [SPI.GPROC]Engineering Sciences [physics]/Chemical and Process Engineering, 0105 earth and related environmental sciences, TEM analysis, 021001 nanoscience & nanotechnology, Soot, BET analysis, Aerosol, Airborne nanostructured particle, Agglomerate, Particle-size distribution, 0210 nano-technology, Nanostructured powder, BET theory, Primary particle size distribution
Abstract

At the present time, no stabilised method exists allowing an estimation of the specific surface area for airborne nanostructured particles (nanoaerosols). Recent toxicological studies have, however, revealed biological effects linked to the surface area of these particles. Only the BET method, which can determine the specific mass surface area of a powder, constitutes a reference both in toxicology and in the materials domain. However, this technique is not applicable to nanostructured aerosols given the mass quantities of particles required (between approximately some mg to hundreds of mg taking into account the limit of quantification of existing BET instruments). To characterise the specific surface area of airborne nanostructured particles, a method based on analysing transmission electron microscopy (TEM) images is proposed. This has recourse in particular to previous work carried out in the area of nanoparticles originating from combustion (soot), and takes into account structural parameters of nanostructured particles including the number distribution of primary particles, their overlap coefficient and the fractal dimension of agglomerates and aggregates. The approach proposed in this work was applied to five commercially-available nanostructured powders of differing natures (SiO 2 , ZrO 2 , Al 2 O 3 , Fe 2 O 3 and Fe 3 O 4 ). This first involved their prior analysis by the BET method and then being placed in suspension in aerosol form using a vortex-type shaker system. The procedure to calculate the specific surface area using image analysis was then applied to the sampled aerosols and compared to the BET measurements. The experimental results obtained on the five nanostructured powders cover a range of specific surface areas from 20 to 200 m 2 /g, the primary particles having mean diameters varying from 7 to 47 nm. Close agreement was observed between the two approaches which, taking into account measurement uncertainties, are statistically equivalent at significance level α = 0.05.

Published
2010
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33. Scattering properties of sands. 1. Comparison between different techniques of measurements

Author

Bertrand Gaubicher, Benoit Couté, Daniel Daugeron, François Gensdarmes, Guillaume Basso, Jean-Baptiste Renard, Edith Hadamcik, Corinne Fournier, Laboratoire de Météorologie Physique (LaMP), Institut national des sciences de l'Univers (INSU - CNRS)-Université Clermont Auvergne [2017-2020] (UCA [2017-2020])-Centre National de la Recherche Scientifique (CNRS), Laboratoire de physique et chimie de l'environnement (LPCE), Institut national des sciences de l'Univers (INSU - CNRS)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS), Service d'aéronomie (SA), 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 Radioprotection et de Sûreté Nucléaire (IRSN), Laboratoire Hubert Curien (LHC), Institut d'Optique Graduate School (IOGS)-Université Jean Monnet - Saint-Étienne (UJM)-Centre National de la Recherche Scientifique (CNRS), Université d'Orléans (UO)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Hubert Curien [Saint Etienne] (LHC), and Université Jean Monnet [Saint-Étienne] (UJM)-Centre National de la Recherche Scientifique (CNRS)-Institut d'Optique Graduate School (IOGS)

Subjects
Physics, [PHYS.PHYS.PHYS-AO-PH]Physics [physics]/Physics [physics]/Atmospheric and Oceanic Physics [physics.ao-ph], 010504 meteorology & atmospheric sciences, Nephelometer, Linear polarization, Scattering, business.industry, Materials Science (miscellaneous), Mie scattering, Airflow, Polarimetry, Polarization (waves), 01 natural sciences, Industrial and Manufacturing Engineering, Light scattering, 010309 optics, Optics, 0103 physical sciences, Business and International Management, business, 0105 earth and related environmental sciences
Abstract

International audience; Measuring linear polarization of light scattered by a cloud of particles can help retrieve their physical properties. We present an extensive study of polarimetric measurements of sand grains that can be found on the surface and in the atmosphere of the Earth. Different techniques of measurements are compared using the Laboratoire de Météorologie Physique nephelometer on the ground and the Propriétés Optiques des Grains Astronomiques et Atmosphériques on the ground and in microgravity during parabolic flights. The techniques used on the ground bias the measurements. When the grains are lifted by an air draft, differentiation is produced in the size distribution and the nature of the floating particles. When the grains are carried along with the airflow, some grains become oriented along the flow direction at air speeds greater than a few meters per second, producing abnormal negative polarization. On the other hand, measurements conducted under microgravity permit the retrieval of the representative optical properties of the lifted sand grains with sizes greater than tens of micrometers.

Published
2006
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34. Adhesion force of W dust on tokamak W plasma-facing surfaces: The importance of the impact velocity

Author

A. Autricque, Christian Grisolia, François Gensdarmes, Samuel Peillon, Mamadou Sow, Institut de Recherche sur la Fusion par confinement Magnétique (IRFM), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Institut de Radioprotection et de Sûreté Nucléaire (IRSN), Laboratoire Matériaux et Durabilité des constructions (LMDC), Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées, PSN-RES/SCA/LPMA, Laboratoire de physique et de métrologie des aérosols (IRSN/PSN-RES/SCA/LPMA), Service du Confinement et de l'Aérodispersion des polluants (IRSN/PSN-RES/SCA), and Institut de Radioprotection et de Sûreté Nucléaire (IRSN)-Institut de Radioprotection et de Sûreté Nucléaire (IRSN)

Subjects
Nuclear and High Energy Physics, Materials science, Tokamak, Orders of magnitude (temperature), Materials Science (miscellaneous), chemistry.chemical_element, Tungsten, 01 natural sciences, 010305 fluids & plasmas, law.invention, [SPI]Engineering Sciences [physics], symbols.namesake, law, 0103 physical sciences, Surface roughness, Composite material, 010302 applied physics, Plasma, Adhesion, lcsh:TK9001-9401, Nuclear Energy and Engineering, chemistry, symbols, lcsh:Nuclear engineering. Atomic power, van der Waals force, Contact area
Abstract

International audience; The adhesion of tungsten (W) dust particles on W tokamak plasma-facing surfaces is investigated. When spherical dust hits the tokamak walls, its shape is altered as a contact area is created by the adhesion work and irreversible plastic deformation. The van der Waals adhesion force between such a deformed grain and a flat surface is estimated, and the link between the force and the impact velocity is determined. We show that adhesion can be increased by several orders of magnitude when the impact velocity approaches the adhesion velocity. Finally, the effects of surface roughness are incorporated. © 2019

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35. Dust sampling in WEST and tritium retention in tokamak-relevant tungsten particles

Author

Nathalie Herlin-Boime, S. Peillon, Sophie Feuillastre, S. Garcia-Argote, C. Arnas, Olivier Pluchery, M. Payet, F. Miserque, François Gensdarmes, Christian Grisolia, Gregoire Dougniaux, E. Bernard, Grégory Pieters, Physique des interactions ioniques et moléculaires (PIIM), Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS), Institut des Nanosciences de Paris (INSP), Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), PSN-RES/SCA/LPMA, Institut de Radioprotection et de Sûreté Nucléaire (IRSN), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Institut de Recherche sur la Fusion par confinement Magnétique (IRFM), Service de la Corrosion et du Comportement des Matériaux dans leur Environnement (SCCME), Département de Physico-Chimie (DPC), CEA-Direction des Energies (ex-Direction de l'Energie Nucléaire) (CEA-DES (ex-DEN)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-CEA-Direction des Energies (ex-Direction de l'Energie Nucléaire) (CEA-DES (ex-DEN)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Institut Rayonnement Matière de Saclay (IRAMIS), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Nanosciences et Innovation pour les Matériaux, la Biomédecine et l'Energie (ex SIS2M) (NIMBE UMR 3685), 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), Laboratoire Edifices Nanométriques (LEDNA), 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), Laboratoire de physique et de métrologie des aérosols (IRSN/PSN-RES/SCA/LPMA), Service du Confinement et de l'Aérodispersion des polluants (IRSN/PSN-RES/SCA), Institut de Radioprotection et de Sûreté Nucléaire (IRSN)-Institut de Radioprotection et de Sûreté Nucléaire (IRSN), 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 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)

Subjects
Nuclear and High Energy Physics, WEST, Tokamak, Materials science, Materials Science (miscellaneous), Nuclear engineering, chemistry.chemical_element, Tungsten, Tritium, 01 natural sciences, Electric charge, 010305 fluids & plasmas, law.invention, law, [PHYS.PHYS.PHYS-PLASM-PH]Physics [physics]/Physics [physics]/Plasma Physics [physics.plasm-ph], 0103 physical sciences, ComputingMilieux_MISCELLANEOUS, [PHYS]Physics [physics], 010302 applied physics, Radioactive waste, Sampling (statistics), Dust, lcsh:TK9001-9401, Nuclear Energy and Engineering, chemistry, Adhesion, lcsh:Nuclear engineering. Atomic power, Particle, Dispersion (chemistry)
Abstract

International audience; The paper presents complementary approaches based on experimental and numerical works to address the behavior of tokamak-relevant tungsten particles loaded with tritium. Sampling of particles inside the WEST tokamak have been realized thanks to an in situ particle collection system called Duster Box. This method allowed to identify various types of tungsten particles among them spherical shaped micro-particles between 5 µm and 30 µm in diameter. Based on these results a surrogate tungsten powder has been provided by means of spheroidization process and sieving method. Moreover, the powder tritium retention capacity was measured and specific activities of 90 MBq.g−1 and 280 MBq.g−1 were obtained for particles with 17 µm and 11.5 µm median diameters, respectively. Considering such tritium activities trapped in the particles, Monte-Carlo simulation were performed to estimate the electrostatic self-charging rates and the corresponding electrical charge carried by the radioactive tungsten dust. The results of these experiments provide robust data for the assessment of the dispersion of toxic/radioactive material in the environment that could follow a loss of containment.

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