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9,670 results on '"Institut National Polytechnique de Toulouse - INPT (FRANCE)"'

1. Using the Finite Element Analysis Method to Study the 3-point Bending Test for the Characterization of the Adherence

Author: Sauvage, Jean-Baptiste, Chalandon, Pierre, Poquillon, Dominique, Nardin, Michel, Aufray, Maëlenn, Centre interuniversitaire de recherche et d'ingenierie des matériaux (CIRIMAT), Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC), Institut de Science des Matériaux de Mulhouse (IS2M), Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Centre National de la Recherche Scientifique (CNRS), CEntre Technique des Industries Mécaniques - Cetim (FRANCE), Centre Technique des Industries Mécaniques - CETIM (FRANCE), Centre National de la Recherche Scientifique - CNRS (FRANCE), Institut National Polytechnique de Toulouse - INPT (FRANCE), Université Toulouse III - Paul Sabatier - UT3 (FRANCE), Université de Haute Alsace - UHA (FRANCE), and Institut National Polytechnique de Toulouse - Toulouse INP (FRANCE)
Subjects: fem, FEM, Matériaux, Stress and strain distribution, Initiation test, adhesive failure, Adhesive failure, [SPI.MAT]Engineering Sciences [physics]/Materials, 3-point bending, initiation test, stress and strain distribution, lcsh:Mechanics of engineering. Applied mechanics, lcsh:TA349-359
Abstract: International audience; An elastic finite element analysis was conducted to evaluate the stress distribution in the initiation zone of the adhesive rupture during the 3-point bending test. This test is used to measure the adherence between a polyepoxy adhesive and aluminum alloy with different surface treatments. The purpose is to compare, in the high stress concentration areas, the stress fields calculated using finite element method with the experimental data obtained in different configurations. Focusing on the load level at crack initiation, on the localization and the size of adhesive failure initiation, a local criterion for adhesive fracture is proposed based on the value of the stress normal to the interface.
Published: 2020
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2. Design of Experiments Predictive Models as a Tool for Lifespan Prediction and Comparison for Enameled Wires Used in Low-Voltage Inverter-Fed Motors

Author: Pascal Maussion, Mateusz Szczepanski, Philippe Manfe, David Malec, LAboratoire PLasma et Conversion d'Energie (LAPLACE), Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées, Matériaux Diélectriques dans la Conversion d’Energie (LAPLACE-MDCE), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), COmmande et DIAgnostic des Systèmes Electriques (LAPLACE-CODIASE), Emerson-Leroy Somer, Centre National de la Recherche Scientifique - CNRS (FRANCE), Institut National Polytechnique de Toulouse - Toulouse INP (FRANCE), Université Toulouse III - Paul Sabatier - UT3 (FRANCE), Leroy-Somer (FRANCE), Nihon Densan Kabushiki Kaisha - NIDEC (JAPAN), and Institut National Polytechnique de Toulouse - INPT (FRANCE)
Subjects: Energie électrique, Computer science, Lifespan prediction, Pulsewidth modulation (PWM), 02 engineering and technology, 01 natural sciences, Comparative method, Industrial and Manufacturing Engineering, Design of experiments (DoE)- Electrical insulation system, Rotating machines, Control theory, Insulation system, 0103 physical sciences, 0202 electrical engineering, electronic engineering, information engineering, Electrical and Electronic Engineering, Inverter-fed motors, 010302 applied physics, [SPI.NRJ]Engineering Sciences [physics]/Electric power, 020208 electrical & electronic engineering, Partial discharge (PD), Control and Systems Engineering, Electromagnetic coil, Overvoltage, Partial discharge, Harmonic, Weibull distribution, Accelerated aging, Low voltage, Pulse-width modulation, Voltage
Abstract: Since the development of power electronic components, which allowed the manufacturing of reliable and efficient inverters, variable speed drives using inductive motors have become more and more popular. The pulsewidth modulation (PWM) technique has proven to be a very effective method of rotational speed control. However, the fast-changing voltage pulses, with very steep slopes (in the order of a few kilovolt/microsecond), have brought new hazards for the electrical insulation system of such motors. Very high frequency harmonic components of PWM voltage will result in significant overvoltage due to an impedance mismatch between the cable and the motor. As an effect, the voltage seen by some parts of the insulation system may exceed the partial discharge inception voltage stating the localized partial discharges activity. The aim of this article is to investigate and analyze the aging process of the enameled wire exposed to different factors and to propose a method allowing them to predict their lifespans in given conditions. This study introduces a prediction based on the design of experiments method and the statistical Weibull distribution. Thanks to the model obtained with short multistress aging tests, it is possible to predict the results of significantly longer ones. Moreover, the adopted methodology is proposed that allows us to predict the scatter of the long tests based on the short-time results dispersion. The same approach is used to compare different products between each other and rank them. All model predictions are compared with the experimental data in order to prove the model accuracy.
Published: 2020
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3. Particles, Drops, and Bubbles Moving Across Sharp Interfaces and Stratified Layers

Author: Jacques Magnaudet, Matthieu Mercier, Institut de mécanique des fluides de Toulouse (IMFT), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées, Massachusetts Institute of Technology (MIT), Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut National Polytechnique (Toulouse) (Toulouse INP), Centre National de la Recherche Scientifique - CNRS (FRANCE), Institut National Polytechnique de Toulouse - Toulouse INP (FRANCE), Université Toulouse III - Paul Sabatier - UT3 (FRANCE), and Institut National Polytechnique de Toulouse - INPT (FRANCE)
Subjects: Drift volume, Mécanique des fluides, [SPI.FLUID]Engineering Sciences [physics]/Reactive fluid environment, Stratified flows, Particle-laden flows, Drops and bubbles, Mechanics, [SPI.MECA]Engineering Sciences [physics]/Mechanics [physics.med-ph], Condensed Matter Physics, 01 natural sciences, [SPI.MECA.MEFL]Engineering Sciences [physics]/Mechanics [physics.med-ph]/Fluids mechanics [physics.class-ph], 010305 fluids & plasmas, Physics::Fluid Dynamics, [SPI]Engineering Sciences [physics], Multiphase flows, 0103 physical sciences, Interfacial flows, 010306 general physics, Geology
Abstract: International audience; Rigid or deformable bodies moving through continuously stratified layers or across sharp interfaces are involved in a wide variety of geophysical and engineering applications, with both miscible and immiscible fluids. In most cases, the body moves while pulling a column of fluid, in which density and possibly viscosity differ from those of the neighboring fluid. The presence of this column usually increases the fluid resistance to the relative body motion, frequently slowing down its settling or rise in a dramatic manner. This column also exhibits specific dynamics that depend on the nature of the fluids and on the various physical parameters of the system, especially the strength of the density/viscosity stratification and the relative magnitude of inertia and viscous effects. In the miscible case, as stratification increases, the wake becomes dominated by the presence of a downstream jet, which may undergo a specific instability. In immiscible fluids, the viscosity contrast combined with capillary effects may lead to strikingly different evolutions of the column , including pinch-off followed by the formation of a drop that remains attached to the body, or a massive fragmentation phenomenon. This review discusses the flow organization and its consequences on the body motion under a wide range of conditions, as well as potentialities and limitations of available models aimed at predicting the body and column dynamics.
Published: 2020
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4. New membranes based on polyethersulfone – SlipSkin™ polymer blends with low fouling and high blood compatibility

Author: Rick J. H. Wetzels, Lydia A.M. Bolhuis-Versteeg, S. Helfrich, Yvonne M. C. Henskens, Denys Pavlenko, Paul W.M. Verhezen, D. Snisarenko, Dimitrios Stamatialis, Pierre Aimar, R. van Oerle, O.E.M. ter Beek, Patrice Bacchin, Christel Causserand, M. Suck, MUMC+: DA CDL Analytisch cluster 1K (9), RS: CARIM - R1.04 - Clinical thrombosis and haemostasis, MUMC+: DA CDL Algemeen (9), Faculteit FHML Centraal, RS: Carim - B04 Clinical thrombosis and Haemostasis, Centre National de la Recherche Scientifique - CNRS (FRANCE), Institut National Polytechnique de Toulouse - Toulouse INP (FRANCE), Maastricht University Medical Center - MUMC (NETHERLANDS), Université Toulouse III - Paul Sabatier - UT3 (FRANCE), University of Twente (NETHERLANDS), European Membrane Institute - EMI (Twente, Netherlands), University of Twente [Netherlands], Laboratoire de génie chimique [ancien site de Basso-Cambo] (LGC), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées, Maastricht University Medical Centre (MUMC), Maastricht University [Maastricht], Institut National Polytechnique de Toulouse - INPT (FRANCE), Biomaterials Science and Technology, and European Membrane Institute
Subjects: Biocompatibility, medicine.medical_treatment, MODIFIER, Filtration and Separation, 02 engineering and technology, STERILIZATION, Artificial kidney, Analytical Chemistry, End stage renal disease, ULTRAFILTRATION MEMBRANES, [CHIM.GENI]Chemical Sciences/Chemical engineering, REMOVAL, 020401 chemical engineering, DIALYSIS, medicine, Génie chimique, [SPI.GPROC]Engineering Sciences [physics]/Chemical and Process Engineering, 0204 chemical engineering, Génie des procédés, UREMIC TOXINS, Chromatography, Fouling, STABILITY, Chemistry, Membrane, HEMOCOMPATIBILITY, COPOLYMER, Sterilization (microbiology), PERFORMANCE, 021001 nanoscience & nanotechnology, 22/4 OA procedure, Hollow fiber membrane, Hemodialysis, 0210 nano-technology
Abstract: International audience; Hemodialysis is an important therapy for treating patients with End Stage Renal Disease (ESRD). These patients visit the hospital 3 times a week and each time their blood is cleansed during 4-hour dialysis sessions using a hollow fiber membrane module; also called artificial kidney. This device mainly achieves removal of small water-soluble toxins and a limited number of middle molecules. To improve the clearance of toxins, especially middle molecules and protein bound toxins, longer treatment via nocturnal dialysis and/or the application of portable/wearable artificial kidney is required. Such therapies require application of membranes with very low fouling and very good blood compatibility. Current membranes often contain hydrophilic additives which could elute during sterilization processes and/or during long-term filtration. In this study, we propose a simple method for developing low fouling blood compatible membranes by blending of polyethersulfone (PES), a material already used for fabrication of dialysis membranes, with small amounts of SlipSkin™ (SS), a blood compatible random copolymer of hydrophilic N-vinylpyrrolidone (NVP) and hydrophobic N-butylmethacrylate (BMA). Our results show that membranes with 2 wt% of SS have high fouling resistance to proteins and middle-size molecules and very good blood compatibility, making these membranes promising for application in dialysis therapy.
Published: 2019
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5. Controlling Solvation and Mass Transport Properties of Biobased Solvents through CO2 Expansion: A Physicochemical and Molecular Modeling Study

Author: Jean-Stéphane Condoret, Vincent Gerbaud, Corinne Lacaze-Dufaure, Emanuel Granero-Fernandez, Yaocihuatl Medina-Gonzalez, Centre National de la Recherche Scientifique - CNRS (FRANCE), Institut National Polytechnique de Toulouse - INPT (FRANCE), Université Toulouse III - Paul Sabatier - UT3 (FRANCE), Institut National Polytechnique de Toulouse - Toulouse INP (FRANCE), Laboratoire de génie chimique [ancien site de Basso-Cambo] (LGC), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées, Centre interuniversitaire de recherche et d'ingenierie des matériaux (CIRIMAT), Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut National Polytechnique (Toulouse) (Toulouse INP), and Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)
Subjects: Chemistry, General Chemical Engineering, Solvatochromism, Solvation, Thermodynamics, 02 engineering and technology, General Chemistry, 021001 nanoscience & nanotechnology, Anisole, Industrial and Manufacturing Engineering, Solvent, gas expanded liquid, Viscosity, chemistry.chemical_compound, Molecular dynamics, [CHIM.GENI]Chemical Sciences/Chemical engineering, 020401 chemical engineering, Polarizability, Génie chimique, [SPI.GPROC]Engineering Sciences [physics]/Chemical and Process Engineering, 0204 chemical engineering, Solubility, Génie des procédés, 0210 nano-technology
Abstract: International audience; Gas-expanded liquids have been studied during past years; however, the physicochemical properties of some of these fluids still need to be characterized and understood. In particular, the study of properties concerning solvation and mass transport is key for industrial applications. This work presents the characterization of eight CO2-expanded biosourced solvents: organic carbonates (dimethyl, diethyl, ethylene, and propylene carbonates), anisole, veratrole, γ-valerolactone, and 2-methyltetrahydrofuran. Two approaches have been used: spectroscopic measurements and molecular modeling. Phase equilibrium was determined for each CO2/biosourced solvent system, and then the solvatochromic probe Nile Red was used to determine changes in dipolarity/polarizability (π* Kamlet–Taft parameter) by CO2 pressure. Molecular dynamics calculations were performed to determine the density and viscosity changes with CO2 pressure. It is shown in this study that the degree of modulation of dipolarity/polarizability parameter can go from that of pure solvent (around 0.4 for linear organic carbonates) to negative values, close to that of pure CO2 at the T and P used in this study. Concerning transport properties, such as density and viscosity, a great decrease in both these properties’ values was observed after swelling of the solvent by CO2, for instance, in linear organic carbonates where density can decrease to 50% the density of pure solvent; concerning viscosity a decrease of up to 90% was measured for these compounds. It was observed that the solubility of CO2 and then modulation of properties were higher in linear organic carbonates than in the cyclic ones. This study shows once more that CO2 has a great capacity to be used as a knob for triggering changes in the physicochemical properties of green biosourced solvents that can help to implement these solvents in industrial applications.
Published: 2019
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6. Designing ionic channels in novel carbons for electrochemical energy storage

Author: Patrice Simon, Jianglin Ye, Yanwu Zhu, Aix-Marseille Université - AMU (FRANCE), Centre National de la Recherche Scientifique - CNRS (FRANCE), Collège de France (FRANCE), Ecole Nationale Supérieure de Chimie de Paris - ENSCP (FRANCE), Ecole Nationale Supérieure de Chimie de Montpellier - ENSCM (FRANCE), Institut National Polytechnique de Toulouse - INPT (FRANCE), Institut polytechnique de Grenoble (FRANCE), Sorbonne Université (FRANCE), Université Toulouse III - Paul Sabatier - UT3 (FRANCE), Université de Nantes (FRANCE), Université de Picardie Jules Verne (FRANCE), Université de Pau et des Pays de l'Adour - UPPA (FRANCE), Université de Haute Alsace - UHA (FRANCE), Université de Montpellier (FRANCE), University of Science and Technology of China - USTC (CHINA), Centre Interuniversitaire de Recherche et d'Ingénierie des Matériaux - CIRIMAT (Toulouse, France), University of Science and Technology of China [Hefei] (USTC), Centre interuniversitaire de recherche et d'ingenierie des matériaux (CIRIMAT), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT), Réseau sur le stockage électrochimique de l'énergie (RS2E), Université de Nantes (UN)-Aix Marseille Université (AMU)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Collège de France (CdF (institution))-Université de Picardie Jules Verne (UPJV)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Ecole Nationale Supérieure de Chimie de Paris - Chimie ParisTech-PSL (ENSCP), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Pau et des Pays de l'Adour (UPPA)-Institut de Chimie du CNRS (INC)-Université de Montpellier (UM)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP ), Université Grenoble Alpes (UGA)-Université Grenoble Alpes (UGA), Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC), Université de Picardie Jules Verne (UPJV)-Institut de Chimie du CNRS (INC)-Aix Marseille Université (AMU)-Université de Pau et des Pays de l'Adour (UPPA)-Université de Nantes (UN)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Sorbonne Université (SU)-Ecole Nationale Supérieure de Chimie de Paris - Chimie ParisTech-PSL (ENSCP), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Collège de France (CdF (institution))-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP ), Université Grenoble Alpes (UGA)-Université Grenoble Alpes (UGA)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM), and Institut National Polytechnique de Toulouse - Toulouse INP (FRANCE)
Subjects: Energie électrique, Materials science, ionic channels, Matériaux, Materials Science, Carbon materials, chemistry.chemical_element, Ionic bonding, Review, 02 engineering and technology, 010402 general chemistry, Electrochemistry, 01 natural sciences, Energy storage, [SPI.MAT]Engineering Sciences [physics]/Materials, Ion, law.invention, Adsorption, law, Multidisciplinary, carbon materials, electrochemical energy storage, [SPI.NRJ]Engineering Sciences [physics]/Electric power, ion kinetics, Ionic channels, 021001 nanoscience & nanotechnology, 0104 chemical sciences, Capacitor, chemistry, Chemical engineering, Electrode, Electrochemical energy storage, Ion kinetics, 0210 nano-technology, Carbon
Abstract: Tremendous efforts have been dedicated to developing high-performance energy storage devices based on the micro- or nano-manipulation of novel carbon electrodes, as certain nanocarbons are perceived to have advantages such as high specific surface areas, superior electric conductivities, excellent mechanical properties and so on. In typical electrochemical electrodes, ions are intercalated/deintercalated into/from the bulk (for batteries) or adsorbed/desorbed on/from the surface (for electrochemical capacitors). Fast ionic transport, significantly determined by ionic channels in active electrodes or supporting materials, is a prerequisite for the efficient energy storage with carbons. In this report, we summarize recent design strategies for ionic channels in novel carbons and give comments on the promising features based on those carbons towards tailorable ionic channels.
Published: 2019
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7. A generalized non-reflecting inlet boundary condition for steady and forced compressible flows with injection of vortical and acoustic waves

Author: Thierry Poinsot, Guillaume Daviller, Gorkem Oztarlik, Centre Européen de Recherche et de Formation Avancée en Calcul Scientifique (CERFACS), CERFACS, Institut de mécanique des fluides de Toulouse (IMFT), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées, Centre National de la Recherche Scientifique - CNRS (FRANCE), Institut National Polytechnique de Toulouse - Toulouse INP (FRANCE), Université Toulouse III - Paul Sabatier - UT3 (FRANCE), Centre Européen de Recherche et Formation Avancées en Calcul Scientifique - CERFACS (FRANCE), and Institut National Polytechnique de Toulouse - INPT (FRANCE)
Subjects: Non reflecting boundary conditions, General Computer Science, Mécanique des fluides, 01 natural sciences, Compressible flow, 010305 fluids & plasmas, Physics::Fluid Dynamics, Turbulence injection, Inlet compressible flow, 0103 physical sciences, Duct (flow), [PHYS.MECA.MEFL]Physics [physics]/Mechanics [physics]/Fluid mechanics [physics.class-ph], Boundary value problem, 0101 mathematics, Characteristic boundary conditions, Premixed flame, Physics, geography, geography.geographical_feature_category, Turbulence, General Engineering, Mechanics, Acoustic wave, Inlet, 010101 applied mathematics, Compressibility, Acoustic forcing
Abstract: International audience; This paper describes a new boundary condition for subsonic inlets in compressible flow solvers. The method uses characteristic analysis based on wave decomposition and the paper discusses how to specify the amplitude of incoming waves to inject simultaneously three-dimensional turbulence and one-dimensional acoustic waves while still being non-reflecting for outgoing acoustic waves. The non-reflecting property is ensured by using developments proposed by Polifke et al. [1, 2]. They are combined with a novel formulation to inject turbulence and acoustic waves simultaneously at an inlet. The paper discusses the compromise which must be sought by the boundary condition formulation between conflicting objectives: respecting target unsteady inlet velocities (for turbulence and acoustics), avoiding a drift of the mean inlet velocities and ensuring non-reflecting performances for waves reaching the inlet from the computational domain. This well-known limit of classical formulations is improved by the new approach which ensures that the mean inlet velocities do not drift, that the unsteady components of velocity (turbulence and acoustics) are correctly introduced into the domain and that the inlet remains non-reflecting. These properties are crucial for forced unsteady flows but the same formulation is also useful for unforced cases where it allows to reach convergence faster. The method is presented by focusing on the expression of the ingoing waves and comparing it with the classical NSCBC approach [3]. Four tests are then described: (1) the injection of acoustic waves through a non reflecting inlet, (2) the compressible flow establishment in a nozzle, (3) the simultaneous injection of turbulence and ingoing acoustic waves into a duct terminated by a reflecting outlet and (4) a turbulent, acoustically forced Bunsen-type premixed flame.
Published: 2019
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8. Core mechanisms of drag enhancement on bodies settling in a stratified fluid

Author: Jie Zhang, Matthieu Mercier, Jacques Magnaudet, Centre National de la Recherche Scientifique - CNRS (FRANCE), Institut National Polytechnique de Toulouse - INPT (FRANCE), Université Toulouse III - Paul Sabatier - UT3 (FRANCE), Xi'an Jiaotong University - XJTU (CHINA), Institut de mécanique des fluides de Toulouse (IMFT), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées, Xi'an Jiaotong University (Xjtu), and Institut National Polytechnique de Toulouse - Toulouse INP (FRANCE)
Subjects: Buoyancy, Mécanique des fluides, Stratified flows, Direct numerical simulation, Stratification (water), engineering.material, 01 natural sciences, 010305 fluids & plasmas, Physics::Fluid Dynamics, Viscosity, Settling, 0103 physical sciences, [PHYS.MECA.MEFL]Physics [physics]/Mechanics [physics]/Fluid mechanics [physics.class-ph], 010306 general physics, Physics, Mechanical Engineering, Mechanics, Vorticity, Ocean processes, Condensed Matter Physics, 13. Climate action, Mechanics of Materials, Drag, Particle/fluid flow, engineering
Abstract: International audience; Stratification due to salt or heat gradients greatly affects the distribution of inert particles and living organisms in the ocean and the lower atmosphere. Laboratory studies considering the settling of a sphere in a linearly stratified fluid confirmed that stratification may dramatically enhance the drag on the body, but failed to identify the generic physical mechanism responsible for this increase. We present a rigorous splitting scheme of the various contributions to the drag on a settling body, which allows them to be properly disentangled whatever the relative magnitude of inertial, viscous, diffusive and buoyancy effects. We apply this splitting procedure to data obtained via direct numerical simulation of the flow past a settling sphere over a range of parameters covering a variety of situations of laboratory and geophysical interest. Contrary to widespread belief, we show that, in the parameter range covered by the simulations, the drag enhancement is generally not primarily due to the extra buoyancy force resulting from the dragging of light fluid by the body, but rather to the specific structure of the vorticity field set in by buoyancy effects. Simulations also reveal how the different buoyancy-induced contributions to the drag vary with the flow parameters. To unravel the origin of these variations, we analyse the different possible leading-order balances in the governing equations. Thanks to this procedure, we identify several distinct regimes which differ by the relative magnitude of length scales associated with stratification, viscosity and diffusivity. We derive the scaling laws of the buoyancy-induced drag contributions in each of these regimes. Considering tangible examples, we show how these scaling laws combined with numerical results may be used to obtain reliable predictions beyond the range of parameters covered by the simulations.
Published: 2019
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9. Assessment of inner–outer interactions in the urban boundary layer using a predictive model

Author: Laurent Perret, Romain Mathis, Karin Blackman, Centre National de la Recherche Scientifique - CNRS (FRANCE), Ecole Centrale de Nantes (FRANCE), Institut National Polytechnique de Toulouse - Toulouse INP (FRANCE), Université Toulouse III - Paul Sabatier - UT3 (FRANCE), Institut National Polytechnique de Toulouse - INPT (FRANCE), Laboratoire de recherche en Hydrodynamique, Énergétique et Environnement Atmosphérique (LHEEA), École Centrale de Nantes (ECN)-Centre National de la Recherche Scientifique (CNRS), Institut de mécanique des fluides de Toulouse (IMFT), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), and Université Fédérale Toulouse Midi-Pyrénées
Subjects: 010504 meteorology & atmospheric sciences, Mécanique des fluides, Turbulent boundary layers, Flow (psychology), Boundary (topology), 01 natural sciences, Signal, [SPI.MECA.MEFL]Engineering Sciences [physics]/Mechanics [physics.med-ph]/Fluids mechanics [physics.class-ph], 010305 fluids & plasmas, Superposition principle, symbols.namesake, 0103 physical sciences, Range (statistics), [PHYS.MECA.MEFL]Physics [physics]/Mechanics [physics]/Fluid mechanics [physics.class-ph], 0105 earth and related environmental sciences, Mathematics, Mechanical Engineering, Atmospheric flows, Mathematical analysis, Reynolds number, Flow–structure interactions, Condensed Matter Physics, Nonlinear system, Boundary layer, Mechanics of Materials, symbols
Abstract: Urban-type rough-wall boundary layers developing over staggered cube arrays with plan area packing density, $\unicode[STIX]{x1D706}_{p}$, of 6.25 %, 25 % or 44.4 % have been studied at two Reynolds numbers within a wind tunnel using hot-wire anemometry (HWA). A fixed HWA probe is used to capture the outer-layer flow while a second moving probe is used to capture the inner-layer flow at 13 wall-normal positions between $1.25h$ and $4h$ where $h$ is the height of the roughness elements. The synchronized two-point HWA measurements are used to extract the near-canopy large-scale signal using spectral linear stochastic estimation and a predictive model is calibrated in each of the six measurement configurations. Analysis of the predictive model coefficients demonstrates that the canopy geometry has a significant influence on both the superposition and amplitude modulation. The universal signal, the signal that exists in the absence of any large-scale influence, is also modified as a result of local canopy geometry suggesting that although the nonlinear interactions within urban-type rough-wall boundary layers can be modelled using the predictive model as proposed by Mathis et al. (J. Fluid Mech., vol. 681, 2011, pp. 537–566), the model must be however calibrated for each type of canopy flow regime. The Reynolds number does not significantly affect any of the model coefficients, at least over the limited range of Reynolds numbers studied here. Finally, the predictive model is validated using a prediction of the near-canopy signal at a higher Reynolds number and a prediction using reference signals measured in different canopy geometries to run the model. Statistics up to the fourth order and spectra are accurately reproduced demonstrating the capability of the predictive model in an urban-type rough-wall boundary layer.
Published: 2019
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10. Analysis and trends for Life Cycle Assessment of olive oil production

Author: Carlos Vaca-Garcia, Claire Vialle, Jean-Pierre Belaud, Gabriela Espadas-Aldana, Caroline Sablayrolles, Laboratoire de Chimie Agro-Industrielle (LCA), Institut National de la Recherche Agronomique (INRA)-Ecole Nationale Supérieure de Chimie de Toulouse, Laboratoire de Génie Chimique (LGC), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées, Chimie Agro-Industrielle (CAI), Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Ecole nationale supérieure des ingénieurs en arts chimiques et technologiques-Institut National de la Recherche Agronomique (INRA), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS), Mexican National Council for Science and Technology (CONACYT Mexico)Consejo Nacional de Ciencia y Tecnologia (CONACyT) [471707], Centre National de la Recherche Scientifique - CNRS (FRANCE), Institut National Polytechnique de Toulouse - INPT (FRANCE), Institut National de la Recherche Agronomique - INRA (FRANCE), Université Toulouse III - Paul Sabatier - UT3 (FRANCE), and Institut National Polytechnique de Toulouse - Toulouse INP (FRANCE)
Subjects: [SDV.SA]Life Sciences [q-bio]/Agricultural sciences, Environmental Engineering, Natural resource economics, 020209 energy, 02 engineering and technology, 010501 environmental sciences, 01 natural sciences, Industrial and Manufacturing Engineering, 12. Responsible consumption, Climate change impact assessment, [CHIM.GENI]Chemical Sciences/Chemical engineering, 0202 electrical engineering, electronic engineering, information engineering, Génie chimique, Environmental Chemistry, [SPI.GPROC]Engineering Sciences [physics]/Chemical and Process Engineering, Génie des procédés, Life-cycle assessment, 0105 earth and related environmental sciences, 2. Zero hunger, Environmental assessment, Critical review, Renewable Energy, Sustainability and the Environment, Impact assessment, business.industry, LCA, 15. Life on land, Technical literature, 13. Climate action, Agriculture, Agro-industry, Environmental science, business, Sciences agricoles, Olive oil
Abstract: International audience; For over 10 years, the olive oil sector has been largely studied through Life Cycle Assessment (LCA). Thus, a review of the numerous results and the different evaluated scenarios is relevant for future LCA studies on this important agro-economic sector of the Mediterranean region. The herein present work, based on scientific and technical literature aims to compare system boundaries, functional units, life cycle inventories, allocation, impact assessments, and interpretations from the currently existing LCAs of olive oil. Furthermore, an analysis of the assessment of biogenic carbon has been carried out among the reviewed papers. As a result, 23 relevant LCA studies on olive oil production or olives cultivation (for olive oil production) were identified. Analysis of the literature converged on an unequivocal environmental hotspot, the agricultural phase; which represents the most impactful phase of the olive oil life cycle, due in particular to fertilisation, pesticides treatment, and irrigation. Waste management and distribution also appear to represent a crucial issue. The comparison work made on climate change impact assessment is on the order of magnitude of 460 kg CO2-eq/ton of olive and 1.6 kg CO2-eq/L of olive oil. This study highlights the complexity of carrying out an LCA on the olive oil sector. At last, best practices and methodological recommendations were matured.
Published: 2019
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11. Influence of temperature and soda concentration in a thermo-mechano-chemical pretreatment for bioethanol production from sweet corn co-products

Author: Monica Del Carmen Fong Lopez, Luc Rigal, Matthieu Rigal, Gérard Vilarem, Virginie Vandenbossche, Institut National Polytechnique de Toulouse - INPT (FRANCE), Institut National de la Recherche Agronomique - INRA (FRANCE), Chimie Agro-Industrielle (CAI), Institut National de la Recherche Agronomique (INRA)-Ecole nationale supérieure des ingénieurs en arts chimiques et technologiques-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées, European Community (Horizon 2020) [654365], Laboratoire de Chimie Agro-Industrielle (LCA), Institut National de la Recherche Agronomique (INRA)-Ecole Nationale Supérieure de Chimie de Toulouse, and Institut National Polytechnique de Toulouse - Toulouse INP (FRANCE)
Subjects: [SDV.SA]Life Sciences [q-bio]/Agricultural sciences, 0106 biological sciences, Xylose, 01 natural sciences, chemistry.chemical_compound, Hydrolysis, Enzymatic hydrolysis, Lignin, Ethanol fuel, Dry matter, Alkaline pretreatment, 010405 organic chemistry, food and beverages, Substrate (chemistry), Pulp and paper industry, 6. Clean water, 0104 chemical sciences, chemistry, Biofuel, Sweet corn co-product, Twin-screw extruder, Agronomy and Crop Science, Sciences agricoles, 010606 plant biology & botany
Abstract: International audience; A continuous process combining an alkaline pretreatment, neutralization and injection of enzymes within a twin screw extruder was previously implemented and demonstrate industrial potential. The present work focuses on the investigation of the effects of alkali and temperature during the alkaline pretreatment of sweet corn co-products (SCC) for the production of fermentable sugars with a lower chemical input. Study of NaOH/SCC and internal temperature was performed in ranges of 4–8% (w/w) and 50–170 °C in a laboratory scale twin screw extruder. Analysis of carbohydrates and lignin of the pretreated biomass was performed and the filtration efficiency was also monitored through extrudate dry matter and filtrate mineral matter. The carbohydrate accessibility and process performances were studied by the enzymatic hydrolysis of the extrudate. Increasing temperature reinforces the effects of soda on solubilization of hemicelluloses, thus a hemicelluloses removal reach more than 50%. At optimal conditions, the cellulose-rich substrate after enzymatic hydrolysis achieve a glucose released of 70%, with glucose and xylose yields of 250 g per 1Kg of dry SCC.
Published: 2019
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12. Influence of Nozzle Cavity on Indirect Vortex- and Entropy-Sound Production

Author: Thierry Schuller, Christophe Schram, Lionel Hirschberg, SJ Steven Hulshoff, Jean Collinet, Centre National de la Recherche Scientifique - CNRS (FRANCE), Institut National Polytechnique de Toulouse - INPT (FRANCE), Université Toulouse III - Paul Sabatier - UT3 (FRANCE), ArianeGroup (FRANCE), Delft University of Technology - TU Delft (NETHERLANDS), von Karman Institute for Fluid Dynamics - VKI (BELGIUM), Institut de Mécanique des Fluides de Toulouse - IMFT (Toulouse, France), Institut National Polytechnique de Toulouse - Toulouse INP (FRANCE), Institut de mécanique des fluides de Toulouse (IMFT), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), and Université Fédérale Toulouse Midi-Pyrénées
Subjects: Physics, 020301 aerospace & aeronautics, Mécanique des fluides, Nozzle, Physics::Optics, Combustion, Aerospace Engineering, 02 engineering and technology, Mechanics, Sound production, 01 natural sciences, [SPI.MECA.MEFL]Engineering Sciences [physics]/Mechanics [physics.med-ph]/Fluids mechanics [physics.class-ph], 010305 fluids & plasmas, Vortex, Physics::Fluid Dynamics, 0203 mechanical engineering, Computer Science::Sound, Condensed Matter::Superconductivity, 0103 physical sciences, Physics::Accelerator Physics
Abstract: International audience; Influence of nozzle cavity on indirect vortex- and entropy-sound production
Published: 2019
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13. Assessment of sediment and organic carbon exports into the Arctic ocean: The case of the Yenisei River basin

Author: G. Espitalier Noël, Jean-Luc Probst, Roman Teisserenc, Clément Fabre, Nikita Tananaev, Sabine Sauvage, J.M. Sanchez Pérez, URePSSS - Activité Physique, Muscle, Santé (APMS), Unité de Recherche Pluridisciplinaire Sport, Santé, Société (URePSSS) - EA 7369 (URePSSS), Université d'Artois (UA)-Université du Littoral Côte d'Opale (ULCO)-Université de Lille-Université d'Artois (UA)-Université du Littoral Côte d'Opale (ULCO)-Université de Lille, Laboratoire Ecologie Fonctionnelle et Environnement (ECOLAB), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Observatoire Midi-Pyrénées (OMP), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées, Institut Ecologie et Environnement (INEE), Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), 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)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Melnikov Permafrost Institute, Ugra Research Institute of Information Technologies (RUSSIA), Observatoire Midi-Pyrénées (OMP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut National Polytechnique (Toulouse) (Toulouse INP), Centre National de la Recherche Scientifique - CNRS (FRANCE), Institut National Polytechnique de Toulouse - Toulouse INP (FRANCE), Université Toulouse III - Paul Sabatier - UT3 (FRANCE), Melnikov Permafrost Institute (RUSSIA), Laboratoire Ecologie Fonctionnelle et Environnement (LEFE), 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)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT), and Institut National Polytechnique de Toulouse - INPT (FRANCE)
Subjects: Environmental Engineering, 0208 environmental biotechnology, Permafrost, 02 engineering and technology, 010501 environmental sciences, 01 natural sciences, Carbon Cycle, Yenisei river, Carbon cycle, Rivers, Climate change feedback, Dissolved organic carbon, SWAT, [SDU.ENVI]Sciences of the Universe [physics]/Continental interfaces, environment, Waste Management and Disposal, Organic carbon, ComputingMilieux_MISCELLANEOUS, 0105 earth and related environmental sciences, Water Science and Technology, Civil and Structural Engineering, Ecologie, Environnement, [SDV.EE]Life Sciences [q-bio]/Ecology, environment, Total organic carbon, Hydrology, Arctic Regions, Ecological Modeling, Global warming, Modeling, Sediment, Pollution, Carbon, 020801 environmental engineering, Arctic, 13. Climate action, Environmental science, Environmental Monitoring
Abstract: International audience; The export of organic carbon export by the rivers to the oceans either as particulate organic carbon (POC) or dissolved organic carbon (DOC) is very sensitive to climate change especially in permafrost affected catchments where soils are very rich in organic carbon. With global warming, organic carbon export in both forms is expected to increase in Arctic regions. It should affect contemporary biogeochemical cycles in rivers and oceans and therefore modify the whole food web. This study tries to understand complex processes involved in sediment, POC and DOC riverine transport in the Yenisei River basin and to quantify their respective fluxes at the river outlet. The SWAT (Soil and Water Assessment Tool) hydrological model is used in this study to simulate water and suspended sediment transfers in the largest Arctic river. POC and DOC export have been quantified with empirical models, adapted from literature for the study case. First, the hydrological model has been calibrated and validated at a daily time step for the 2003–2008 and the 2009–2016 periods respectively, and its output has been compared with field data for water and sediment fluxes. Based on conceptualization of transfer processes, calibration on climate and soil properties has been performed in order to correctly represent hydrology and sediment transfer in permafrost basins. Second, calibration of empirical models for DOC/POC transport have been performed by comparing their output with field data, available from 2003 to 2016. Our study reveals that SWAT is capable of correctly representing hydrology, sediment transfer, POC and DOC fluxes and their spatial distribution at a daily timescale, and outlines the links between these fluxes and permafrost features. Our simulation effort results in specific sediment, POC and DOC fluxes of 2.97 t km−2 yr−1, 0.13 t km−2 yr−1 and 1.14 t km−2 yr−1 for the period 2003–2016 which are in the range of previous estimates. About 60% of the total fluxes of sediment, DOC and POC to the Arctic Ocean are exported during the two months of the freshet. Spatial analysis show that permafrost-free areas have returned higher daily organic carbon export than permafrost affected zones, highlighting the thawing permafrost effect on carbon cycle in climate change feedback.
Published: 2019
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14. Effect of sub-surface hydrogen on intrinsic crack tip plasticity in aluminium

Author: Döme Tanguy, Yu Wang, Damien Connétable, Modélisation de la matière condensée et des interfaces (MMCI), Institut Lumière Matière [Villeurbanne] (ILM), Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon, Centre interuniversitaire de recherche et d'ingenierie des matériaux (CIRIMAT), Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC), Centre National de la Recherche Scientifique - CNRS (FRANCE), Institut National Polytechnique de Toulouse - INPT (FRANCE), Université Toulouse III - Paul Sabatier - UT3 (FRANCE), Université Claude Bernard-Lyon I - UCBL (FRANCE), and Institut National Polytechnique de Toulouse - Toulouse INP (FRANCE)
Subjects: Cracking, Surface (mathematics), Materials science, Hydrogen, Matériaux, Dislocations, chemistry.chemical_element, 02 engineering and technology, Plasticity, 01 natural sciences, Condensed Matter::Materials Science, Aluminium, Atomistic simulation, 0103 physical sciences, Hydrogen in metals, Composite material, 010302 applied physics, 021001 nanoscience & nanotechnology, Condensed Matter Physics, Mixed mode, Fracture, chemistry, [PHYS.COND.CM-MS]Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci], Fracture (geology), Dislocation, 0210 nano-technology
Abstract: International audience; The effects of sub-surface hydrogen and mixed mode loading on dislocation emission in aluminium are studied using a combination of techniques including: crack simulations with an empirical interatomic potential, generalised stacking fault energy (GSF) calculations, with empirical interactions and Density Functional Theory, and the model by Rice which links the critical stress intensity factor to the unstable stacking energy. The crack orientation is {111} 112 and the loading is composed of a moderate traction along 111 and a shear along 112 , such that Shockley partials are emitted along the crack plane. The role of the relaxations around the H atoms and of the concentration of H in the glide plane, in the GSF calculation, are revealed by comparing Rice's model to the results of brute force simulations. The enhanced GSF is then calculated ab initio. The conclusion is a large decrease of the critical load to emit a dislocation, due to the displacement transverse to the glide direction. The effect of sub-surface hydrogen is negligible with respect to the mechanical one.
Published: 2019
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15. Impact of the Acoustic Forcing Level on the Transfer Matrix of a Turbulent Swirling Combustor with and Without Flame

Author: Marco Gatti, Thierry Schuller, Renaud Gaudron, Clément Mirat, Laboratoire d'Énergétique Moléculaire et Macroscopique, Combustion (EM2C), CentraleSupélec-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Institut de mécanique des fluides de Toulouse (IMFT), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées, Université Paris Saclay (COmUE)-Centre National de la Recherche Scientifique (CNRS)-CentraleSupélec, Centre National de la Recherche Scientifique - CNRS (FRANCE), Institut National Polytechnique de Toulouse - INPT (FRANCE), Université Paris-Saclay (FRANCE), Université Toulouse III - Paul Sabatier - UT3 (FRANCE), and Institut National Polytechnique de Toulouse - Toulouse INP (FRANCE)
Subjects: Acoustic network model, Thermoacoustic instabilities, General Chemical Engineering, General Physics and Astronomy, 02 engineering and technology, 01 natural sciences, 010305 fluids & plasmas, law.invention, 0203 mechanical engineering, law, 0103 physical sciences, Acoustic damping, Flame describing function, Physical and Theoretical Chemistry, Network model, Physics, Premixed flame, Dimensionless acoustic transfer matrix, Turbulence, Describing function, Laminar flow, Injector, Mechanics, [CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistry, Nonlinear system, 020303 mechanical engineering & transports, Combustor, Nonlinear flame dynamics, Chimie théorique et/ou physique
Abstract: International audience; Thermoacoustic instabilities are a major issue for industrial and domestic burners. One possible framework to study these instabilities is to represent the system by a network of Dimensionless Acoustic Transfer Matrices (DATM) that link pressure and velocity fluctu- ations upstream and downstream each element of the network. In this article, the DATM coefficients of a turbulent swirling combustor are determined for a thermoacoustically stable configuration using harmonic acoustic forcing. Since the dynamics of the whole system is controlled by nonlinearities, the impact of the forcing level needs to be considered. The four DATM coefficients are thus measured for reactive operating conditions (premixed flame) and cold flow conditions for increasing acoustic excitation levels. The velocity level is con- trolled by a hot wire located inside the injector, in a region with a laminar top-hat velocity profile. The upstream and downstream specific acoustic impedances are also measured. Results for the acoustic response under cold flow conditions are first presented. In this case, the DATM coefficients are found to be independent of the forcing level except for the modu- lus of the coefficients linking the downstream velocity fluctuations to the upstream pressure and velocity fluctuations. This behavior is linked to the nonlinear response of the injector but is not entirely captured by the acoustic network model developed in this work. For reac- tive operating conditions, measurements indicate that all DATM coefficients depend on the forcing level to a certain extent. The Flame Describing Function, linking heat release rate fluctuations to velocity fluctuations, is used to reconstruct the transfer matrix through an acoustic network model. This network model accurately predicts the trend of the measured coefficients but the impact of the forcing level is not reproduced. Saturation for reactive operating conditions is shown to be not only related to the nonlinear flame response but also to the nonlinear injector dynamics. Finally, a data-driven reconstruction of the FDF using the acoustic network model along with the hot wire and microphone measurements is per- formed. This data-driven acoustic reconstruction is subsequently compared with the FDF determined with an optical technique.
Published: 2019
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16. Insights into the Crystal Structure and Clathration Selectivity of Organic Clathrates Formed with Hydroquinone and (CO2 + CH4) Gas Mixtures

Author: Antonio Comesaña, Jean-Philippe Torré, Romuald Coupan, Christophe Dicharry, Manuel M. Piñeiro, Martín Pérez-Rodríguez, Heinz Gornitzka, Laboratoire de Génie Chimique (LGC), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées, Laboratoire de chimie de coordination (LCC), Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie de Toulouse (ICT-FR 2599), Université Fédérale Toulouse Midi-Pyrénées-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-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Laboratoire des Fluides Complexes et leurs Réservoirs (LFCR), TOTAL FINA ELF-Université de Pau et des Pays de l'Adour (UPPA)-Centre National de la Recherche Scientifique (CNRS), University of Vigo [ Pontevedra], Université de Toulouse (UT)-Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT), Institut de Chimie de Toulouse (ICT), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS), CNRS (Centre National de la Recherche Scientifique), Ministerio de Economiá y Competitividad (grant FIS2015-68910-P cofinanced by European Regional Development Funds (ERDF)), Centre National de la Recherche Scientifique - CNRS (FRANCE), Institut National Polytechnique de Toulouse - INPT (FRANCE), Total (FRANCE), Université Toulouse III - Paul Sabatier - UT3 (FRANCE), Université de Pau et des Pays de l'Adour - UPPA (FRANCE), Universidade de Vigo - UVIGO (SPAIN), Institut Pluridisciplinaire de Recherche Appliquée (IPRA, Pau), and Institut National Polytechnique de Toulouse - Toulouse INP (FRANCE)
Subjects: Diffraction, Gas Mixtures, Materials science, Molecular model, Organic Clathrates, Clathrate hydrate, 02 engineering and technology, Crystal structure, 010402 general chemistry, 01 natural sciences, chemistry.chemical_compound, Molecular dynamics, Phase (matter), [CHIM.CRIS]Chemical Sciences/Cristallography, Génie chimique, [CHIM.COOR]Chemical Sciences/Coordination chemistry, Physical and Theoretical Chemistry, Génie des procédés, Hydroquinone, 021001 nanoscience & nanotechnology, 0104 chemical sciences, Surfaces, Coatings and Films, Electronic, Optical and Magnetic Materials, General Energy, chemistry, Physical chemistry, Astrophysics::Earth and Planetary Astrophysics, 0210 nano-technology, Selectivity
Abstract: International audience; Organic clathrates, particularly those formed by hydroquinone (HQ) and gas mixtures, have been far less studied than other inclusion compounds, such as gas hydrates. In this study, experiments and molecular dynamics simulations were performed on mixed (CO2 + CH4)–HQ clathrates. Single crystals were synthesized using gas mixtures with different compositions, ranging from pure CO2 to pure CH4. The crystal structure, the guest occupancy in the clathrates, and the variation of the crystal lattice parameters according to clathrate composition were obtained by X-ray diffraction measurements. In addition, molecular dynamics simulations were performed on the same systems, with state-of-the-art molecular models and force fields. The experimental results obtained and the molecular dynamics simulation estimations were in good agreement. The clathration selectivity was also calculated on the basis of experimental results, and the composition of the solid phase was correlated with the composition of the gas phase at equilibrium. These new insights into these structures will be useful from both a fundamental and a practical point of view, particularly for further developing innovative gas separation techniques using HQ clathrates.
Published: 2019
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17. Preventing the propagation of a new kind of illegitimate apps

Author: Alain Tchana, Giang Son Tran, Lavoisier Wapet, Daniel Hagimont, Centre National de la Recherche Scientifique - CNRS (FRANCE), Institut National Polytechnique de Toulouse - Toulouse INP (FRANCE), Université Toulouse III - Paul Sabatier - UT3 (FRANCE), Université des Sciences et des Technologies de Hanoi - USTH (VIETNAM), Université Toulouse - Jean Jaurès - UT2J (FRANCE), Université Toulouse 1 Capitole - UT1 (FRANCE), Institut National Polytechnique de Toulouse - INPT (FRANCE), Système d’exploitation, systèmes répartis, de l’intergiciel à l’architecture (IRIT-SEPIA), Institut de recherche en informatique de Toulouse (IRIT), Université Toulouse 1 Capitole (UT1), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse - Jean Jaurès (UT2J)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse 1 Capitole (UT1), Université Fédérale Toulouse Midi-Pyrénées, Hanoi University of Science and Technology (HUST), and Institut National Polytechnique (Toulouse) (Toulouse INP)
Subjects: [INFO.INFO-AR]Computer Science [cs]/Hardware Architecture [cs.AR], Focus (computing), Computer Networks and Communications, Computer science, Système d'exploitation, Mobile apps, Réseaux et télécommunications, 020206 networking & telecommunications, 02 engineering and technology, Computer security, computer.software_genre, Systèmes embarqués, [INFO.INFO-NI]Computer Science [cs]/Networking and Internet Architecture [cs.NI], Detection, Architectures Matérielles, Fake apps, Hardware and Architecture, 0202 electrical engineering, electronic engineering, information engineering, [INFO.INFO-ES]Computer Science [cs]/Embedded Systems, 020201 artificial intelligence & image processing, [INFO.INFO-OS]Computer Science [cs]/Operating Systems [cs.OS], computer, Software
Abstract: International audience; A significant amount of apps submitted to mobile market places (MMP) are illegitimate, resulting in a negative publicity for these MMPs. To our knowledge, all scanning solutions in this domain only focus on the detection of illegitimate apps which mimic existing ones. However, recent attack analysis reveal the appearance of a new category of victims: enterprises which did not yet publish their app on the MMP. Thereby, an attacker may be one step ahead and publish a malicious app using the graphic identity of a trusted enterprise. Famous enterprises such as Blackberry, Netflix, and Niantic (Pokemon Go) have been subject of such attacks. We designed and implemented a security check system called IMAD (IllegitimateMobile App Detector) which is able to limit aforementioned attacks. The evaluation results show that IMAD can protect companies from such attacks with an acceptable error rate and at a low cost for MMPs.
Published: 2019
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18. Electrical properties of double-wall carbon nanotubes nanocomposite hydrogels

Author: Muriel Golzio, Jean-François Guillet, Emmanuel Flahaut, Zarel Valdez-Nava, Centre interuniversitaire de recherche et d'ingenierie des matériaux (CIRIMAT), Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC), Institut de pharmacologie et de biologie structurale (IPBS), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées, Matériaux Diélectriques dans la Conversion d’Energie (LAPLACE-MDCE), LAboratoire PLasma et Conversion d'Energie (LAPLACE), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées, Centre National de la Recherche Scientifique - CNRS (FRANCE), Institut National Polytechnique de Toulouse - INPT (FRANCE), Université Toulouse III - Paul Sabatier - UT3 (FRANCE), and Institut National Polytechnique de Toulouse - Toulouse INP (FRANCE)
Subjects: Materials science, Matériaux, Carbon nanotubes, Nanotechnology, 02 engineering and technology, Carbon nanotube, 010402 general chemistry, Smart material, 01 natural sciences, law.invention, law, Electrical resistivity and conductivity, Electrical conductivity, General Materials Science, Nanocomposite, Polymer-matrix composites, Direct current, Smart materials, [CHIM.MATE]Chemical Sciences/Material chemistry, General Chemistry, 021001 nanoscience & nanotechnology, Thermal conduction, 0104 chemical sciences, Dielectric spectroscopy, Self-healing hydrogels, 0210 nano-technology
Abstract: International audience; The electrical behaviour of nanocomposite hydrogels and especially hydrogels containing carbon nanotubes is generally poorly understood. In this paper, we investigate the influence of double-wall carbon nanotubes (DWCNT) content on the electrical properties of agarose/DWCNT nanocomposite hydrogels. These nanocomposite hydrogels are potential candidates as electrode materials for transdermal drug delivery by electropermeabilization. Both alternating current (AC) and direct current (DC) measurements at different voltage amplitudes were performed, as well impedance spectroscopy (1 Hz–1 MHz). Data suggest a non-linear dependence of the conduction phenomena vs the applied electric field. From the current-voltage characteristics, the nanocomposite conduction phenomenon is narrowed to two possible mechanisms, a Schottky type or a Poole-Frenkel type. These findings are the first step towards the understanding of the conduction phenomena in such complex nanocomposite structures, comprising DWCNT, water and the 3D polymeric network. The work described in this work is of much wider interest because this kind of nanocomposites may have many other applications, while the fundamental questions about their electrical conductivity remain universal.
Published: 2019
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19. Experimental investigation of heat transport in inhomogeneous bubbly flow

Author: Dennis P. M. van Gils, Biljana Gvozdić, Elise Alméras, Sander G. Huisman, Chao Sun, Detlef Lohse, On Yu Dung, University of Twente [Netherlands], Laboratoire de génie chimique [ancien site de Basso-Cambo] (LGC), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées, Tsinghua University [Beijing] (THU), Centre National de la Recherche Scientifique - CNRS (FRANCE), Institut National Polytechnique de Toulouse - INPT (FRANCE), Université Toulouse III - Paul Sabatier - UT3 (FRANCE), Tsinghua University (CHINA), University of Twente (NETHERLANDS), Laboratoire de Génie Chimique - LGC (Toulouse, France), Physics of Fluids, and Institut National Polytechnique de Toulouse - Toulouse INP (FRANCE)
Subjects: Work (thermodynamics), Materials science, Buoyancy, General Chemical Engineering, Flow (psychology), Mixing (process engineering), UT-Hybrid-D, FOS: Physical sciences, 02 engineering and technology, engineering.material, Industrial and Manufacturing Engineering, Physics::Fluid Dynamics, [CHIM.GENI]Chemical Sciences/Chemical engineering, 020401 chemical engineering, Heat transfer, Génie chimique, [SPI.GPROC]Engineering Sciences [physics]/Chemical and Process Engineering, 0204 chemical engineering, Génie des procédés, Bubbly flows, Turbulence, Applied Mathematics, Fluid Dynamics (physics.flu-dyn), Physics - Fluid Dynamics, General Chemistry, Rayleigh number, Mechanics, 021001 nanoscience & nanotechnology, Volumetric flow rate, engineering, 0210 nano-technology, Experiments, Bubble column
Abstract: In this work we study the heat transport in inhomogeneous bubbly flow. The experiments were performed in a rectangular bubble column heated from one side wall and cooled from the other, with millimetric bubbles introduced through one half of the injection section (close to the hot wall or close to the cold wall). We characterise the global heat transport while varying two parameters: the gas volume fraction $\alpha = 0.4\% - 5.1 \%$, and the Rayleigh number $Ra_H=4\times10^9-2.2\times10^{10}$. As captured by imaging and characterised using Laser Doppler Anemometry (LDA), different flow regimes occur with increasing gas flow rates. In the generated inhomogeneous bubbly flow there are three main contributions to the mixing: (\textit{i}) transport by the buoyancy driven recirculation, (\textit{ii}) bubble induced turbulence (BIT) and (\textit{iii}) shear-induced turbulence (SIT). The strength of these contributions and their interplay depends on the gas volume fraction which is reflected in the measured heat transport enhancement. We compare our results with the findings for heat transport in homogeneous bubbly flow from Gvozdi{\'c} \emph{et al.} (2018). We find that for the lower gas volume fractions ($\alpha4\%$, when the contribution of SIT becomes stronger, but so does the competition between all three contributions, the homogeneous injection is more efficient.
Published: 2019
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20. Multiple description coding technique to improve the robustness of ACELP based coders AMR-WB

Author: Hocine Chaouch, Philippe Marthon, Fatiha Merazka, Centre National de la Recherche Scientifique - CNRS (FRANCE), Institut National Polytechnique de Toulouse - Toulouse INP (FRANCE), Université Toulouse III - Paul Sabatier - UT3 (FRANCE), Université des Sciences et de la Technologie Houari Boumediene - USTHB (ALGERIA), Université Toulouse - Jean Jaurès - UT2J (FRANCE), Université Toulouse 1 Capitole - UT1 (FRANCE), Institut de Recherche en Informatique de Toulouse - IRIT (Toulouse, France), and Institut National Polytechnique de Toulouse - INPT (FRANCE)
Subjects: Linguistics and Language, Computer science, Mean opinion score, Speech recognition, Linear prediction, 02 engineering and technology, MUSHRA, 01 natural sciences, Language and Linguistics, ITU-T G.722.2, Packet loss, Robustness (computer science), 0103 physical sciences, 0202 electrical engineering, electronic engineering, information engineering, Traitement du signal et de l'image, 010301 acoustics, WB-PESQ, Communication, Multiple description coding, 020206 networking & telecommunications, Algebraic code-excited linear prediction, Markov model, Computer Science Applications, Packet loss concealment, VoIP, Modeling and Simulation, Computer Vision and Pattern Recognition, Software
Abstract: In this paper, a concealment method based on multiple-description coding (MDC) is presented, to improve speech quality deterioration caused by packet loss for algebraic code-excited linear prediction (ACELP) based coders. We apply to the ITU-T G.722.2 coder, a packet loss concealment (PLC) technique, which uses packetization schemes based on MDC. This latter is used with two new designed modes, which are modes 5 and 6 (18,25 and 19,85 kbps, respectively). We introduce our new second-order Markov chain model with four states in order to simulate network losses for different loss rates. The performance measures, with objective and subjective tests under various packet loss conditions, show a significant improvement of speech quality for ACELP based coders. The wideband perceptual evaluation of speech quality (WB-PESQ), enhanced modified bark spectral distortion (EMBSD), mean opinion score (MOS) tests and MUltiple Stimuli with Hidden Reference and Anchor (MUSHRA) for speech extracted from TIMIT database confirm the efficiency of our proposed approach and show a considerable enhancement in speech quality compared to the embedded algorithm in the standard ITU-T G.722.2.
Published: 2019
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21. Transient and steady states of Gd2Zr2O7 and 2ZrO2∙Y2O3 (ss) interactions with calcium magnesium aluminium silicates

Author: Philippe Gomez, Andre Malie, Elodie Delon, Jean-Pierre Bonino, Aurélien Joulia, Sandrine Nathalie Duluard, Florence Ansart, Luc Bianchi, Centre National de la Recherche Scientifique - CNRS (FRANCE), Direction Générale pour l'Armement - DGA (FRANCE), Institut National Polytechnique de Toulouse - Toulouse INP (FRANCE), Université Toulouse III - Paul Sabatier - UT3 (FRANCE), SAFRAN (FRANCE), DGA Techniques aéronautiques (Balma, France), Centre interuniversitaire de recherche et d'ingenierie des matériaux (CIRIMAT), Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC), SAFRAN Group, DGA - Techniques aéronautiques, Direction générale de l'Armement (DGA), and Institut National Polytechnique de Toulouse - INPT (FRANCE)
Subjects: Morphology (linguistics), Materials science, Matériaux, Kinetics, Analytical chemistry, Pellets, Reaction products, Nanoparticle, chemistry.chemical_element, 02 engineering and technology, 01 natural sciences, [SPI.MAT]Engineering Sciences [physics]/Materials, Aluminium, 0103 physical sciences, Materials Chemistry, Penetration depth, 010302 applied physics, [CHIM.MATE]Chemical Sciences/Material chemistry, Atmospheric temperature range, 021001 nanoscience & nanotechnology, chemistry, 2ZrO2∙Y2O3 (ss), Ceramics and Composites, Gd2Zr2O7, CMAS tightness, 0210 nano-technology, Quantitative analysis (chemistry)
Abstract: International audience; Reactions between calcium magnesium aluminium silicates (CMAS) and Gd2Zr2O7 or 2ZrO2∙Y2O3 (ss) are investigated within a temperature range of 1200–1300 °C and for durations of 1 h–100 h. The evolution of CMAS penetration depth in Gd2Zr2O7 and 2ZrO2∙Y2O3 (ss) pellets varies considerably depending on the interaction time. A quantitative analysis of the nature and composition of phases observed in stationary conditions (powder/powder interaction) is performed by SEM-FEG coupled with WDS analyses using micro-agglomerated nanoparticles of Gd2Zr2O7 and 2ZrO2∙Y2O3. Faster kinetics of the gadolinium-based system are illustrated through an analysis of the morphology of the reaction area and of the resulting CMAS tightness of reaction products. The compositions and quantities of reaction products observed at equilibrium are very similar for the two systems, but transient states are significantly different.
Published: 2019
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22. Evolution of crystallinity of PEEK and glass-fibre reinforced PEEK under tribological conditions using Raman spectroscopy

Author: Valérie Nassiet, Florentin Berthet, F. Chabert, Jean Denape, F. Ferry, Karl Delbé, Tiphaine Mérian, Marie Doumeng, Olivier Marsan, Laboratoire Génie de Production (LGP), Ecole Nationale d'Ingénieurs de Tarbes (ENIT), Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Université de Toulouse (UT), Institut Clément Ader (ICA), Institut Supérieur de l'Aéronautique et de l'Espace (ISAE-SUPAERO)-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), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-IMT École nationale supérieure des Mines d'Albi-Carmaux (IMT Mines Albi), Institut Mines-Télécom [Paris] (IMT)-Institut Mines-Télécom [Paris] (IMT), Centre interuniversitaire de recherche et d'ingenierie des matériaux (CIRIMAT), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT), Centre National de la Recherche Scientifique - CNRS (FRANCE), Ecole nationale supérieure des Mines d'Albi-Carmaux - IMT Mines Albi (FRANCE), Institut National Polytechnique de Toulouse - Toulouse INP (FRANCE), Institut National des Sciences Appliquées de Toulouse - INSA (FRANCE), Institut Supérieur de l'Aéronautique et de l'Espace - ISAE-SUPAERO (FRANCE), Université Toulouse III - Paul Sabatier - UT3 (FRANCE), Ecole Nationale d'Ingénieurs de Tarbes, Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-IMT École nationale supérieure des Mines d'Albi-Carmaux (IMT Mines Albi), Institut Mines-Télécom [Paris] (IMT)-Institut Mines-Télécom [Paris] (IMT)-Institut Supérieur de l'Aéronautique et de l'Espace (ISAE-SUPAERO), Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC), and Institut National Polytechnique de Toulouse - INPT (FRANCE)
Subjects: Tribology, Materials science, Glass fiber, 02 engineering and technology, law.invention, [PHYS.MECA.MEMA]Physics [physics]/Mechanics [physics]/Mechanics of materials [physics.class-ph], Crystallinity, symbols.namesake, PEEK, 0203 mechanical engineering, law, Materials Chemistry, Peek, Composite material, Crystallization, Fibreglass, Surfaces and Interfaces, 021001 nanoscience & nanotechnology, Condensed Matter Physics, Surfaces, Coatings and Films, 020303 mechanical engineering & transports, Mechanics of Materials, Raman spectroscopy, symbols, Mécanique des matériaux, 0210 nano-technology
Abstract: WOM 2019 - 22nd International Conference on Wear of Materials, 14-18 April 2019, Hyatt Regency Miami, Miami, FL, USA; International audience; A comparative study of PEEK and glass-fibre reinforced PEEK was performed to describes the degradationmechanisms in sliding conditions. Results were focused on Raman spectroscopy data in order to determine thelocal crystallinity rate of PEEK and to complete the scenario of degradation by taking into account the micro-structure transformation during the wear tests. In thefirst period of the test, an amorphisation mechanism ofboth materials is identified. Then, during the second period of the test, these materials reach the glass transitiontemperature, and a cold crystallisation is detected in the wear track.
Published: 2019
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23. Reduction of stream nitrate concentrations by land management in contrasted landscapes

Author: Laurène Casal, Nouraya Akkal-Corfini, Jordy Salmon-Monviola, Anne Probst, Patrick Durand, Cyril Benhamou, Françoise Vertès, Sylvain Ferrant, François Laurent, Jean-Luc Probst, AgroParisTech (FRANCE), Centre National d'Études Spatiales - CNES (FRANCE), Centre National de la Recherche Scientifique - CNRS (FRANCE), Institut National Polytechnique de Toulouse - Toulouse INP (FRANCE), Institut National de la Recherche Agronomique - INRA (FRANCE), Institut de Recherche pour le Développement - IRD (FRANCE), Université Toulouse III - Paul Sabatier - UT3 (FRANCE), ARVALIS - Institut du végétal (FRANCE), Centre d'Etudes Spatiales de la Biosphère - CESBIO (Toulouse, France), Sol Agro et hydrosystème Spatialisation (SAS), AGROCAMPUS OUEST, Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut National de la Recherche Agronomique (INRA), Ecologie fonctionnelle et écotoxicologie des agroécosystèmes (ECOSYS), Institut National de la Recherche Agronomique (INRA)-AgroParisTech, ARVALIS - Institut du végétal [Paris], Centre d'études spatiales de la biosphère (CESBIO), Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut national des sciences de l'Univers (INSU - 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)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Ecologie Fonctionnelle et Environnement (ECOLAB), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut Ecologie et Environnement (INEE), Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-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)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS), French National Research Agency (ESCAPADE project in AGROBIOSPHERE program) : ANR-12-AGRO-0003 Agence de l'Eau Adour Garonne (BAG'AGES project, MOSAIC project of the AGROBIOSPHERE program : ANR-12-AGRO-0005, Arvalis, AGROCAMPUS OUEST-Institut National de la Recherche Agronomique (INRA), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Observatoire Midi-Pyrénées (OMP), Université Fédérale Toulouse Midi-Pyrénées-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées, and Institut National Polytechnique de Toulouse - INPT (FRANCE)
Subjects: Riparian zone, Riparian buffer, [SDE.MCG]Environmental Sciences/Global Changes, Biodiversité et Ecologie, Land management, Soil Science, Context (language use), [SDV.SA.SDS]Life Sciences [q-bio]/Agricultural sciences/Soil study, 010501 environmental sciences, Best management practice, Catchment, 01 natural sciences, Mitigation scenario, chemistry.chemical_compound, [SDV.EE.ECO]Life Sciences [q-bio]/Ecology, environment/Ecosystems, Nitrate, [SDU.STU.GC]Sciences of the Universe [physics]/Earth Sciences/Geochemistry, [SDU.STU.HY]Sciences of the Universe [physics]/Earth Sciences/Hydrology, Nitrogen cycle, ComputingMilieux_MISCELLANEOUS, 0105 earth and related environmental sciences, 2. Zero hunger, Hydrology, geography, geography.geographical_feature_category, [SDE.IE]Environmental Sciences/Environmental Engineering, 04 agricultural and veterinary sciences, 15. Life on land, 6. Clean water, Water Framework Directive, chemistry, 13. Climate action, 040103 agronomy & agriculture, 0401 agriculture, forestry, and fisheries, Environmental science, [SDE.BE]Environmental Sciences/Biodiversity and Ecology, Agronomy and Crop Science, Groundwater, Distributed model, Nitrogen cycling
Abstract: International audience; Optimizing management practices at the plot scale is sometimes not sufficient to reach water framework directive objectives for nitrate pollution. Land management measures involving targeted setting aside of croplands is a promising solution, but its efficiency depends on the local context. We used a distributed agro-hydrological model to compare management interventions intended to decrease vertical and lateral nitrate leaching from soil to groundwater and stream water in two contrasted agricultural catchments. The simulated scenarios combined two strategies: optimization of agricultural practices and land-use conversion from agricultural to natural land at different locations within the catchments. Long- term climate, discharge, and nitrate concentrations have been monitored for the two catchments and agricultural practices are well known over the 13-year simulation period (2002-2015). The Kervidy-Naizin site (KN) is subject to intense livestock pressure with mean nitrogen inputs of 257 kg ha(-1) year while the Aurade site (AU) is primarily cereal cultivation with nitrogen inputs of 109 kg ha(-1) year(-1). The results highlight a large nitrogen legacy in KN, resulting in a progressive and long lived (> 10 years) response to changes in management, while in AU, this response is perceptible after only 5-7 years. For both catchments, the most effective scenario involves wide riparian buffer strips in interception position covering about 15% of the catchment area. In KN, this land conversion scenario, simulated with the agro-hydrological model TNT2, created a decrease of nitrate concentration in stream water by 25% versus 15% in AU. Contrastingly, the implementation of best management practices decreased stream nitrate concentration only by 9% for KN and 4% for AU.
Published: 2019
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24. The efficiency of organizational withdrawal vs commitment

Author: Sibertin-Blanc, Christophe, Terán, Oswaldo, Centre National de la Recherche Scientifique - CNRS (FRANCE), Institut National Polytechnique de Toulouse - INPT (FRANCE), Universidad de Los Andes (VENEZUELA), Université Toulouse III - Paul Sabatier - UT3 (FRANCE), Université Toulouse - Jean Jaurès - UT2J (FRANCE), Université Toulouse 1 Capitole - UT1 (FRANCE), and Institut National Polytechnique de Toulouse - Toulouse INP (FRANCE)
Subjects: Autre, Social simulation, Organizational commitment, Computational social science, Organizational withdrawal, Organizational withdrawal - Actors, Actors
Abstract: Actors within an organization usually do not behave as expected at design-time. There are diverse reasons for this, notably the actors' motivation and organizational commitment. In this paper, we explore the efficiency of a concrete public organization in the context of the Latin-American culture, to the light of the organizational commitment of its members. In order to evaluate how much each member of the organization is committed, we associate to each one a parameter that quantifies its commitment and we evaluate by simulation the impact of this parameter on its behavior an the organization performance. With a model of the organization as it was intended to operate at its foundation, we proceed to a number of simulations to find the parameter values that yield the actual observed working of the organization. By the way, we found that withdrawn behaviors have much more impact than committed ones.
Published: 2021

25. Méthode basée ‘modèle’ pour le diagnostic de l'état de santé d'une pile à combustible PEMFC en vue de sa maintenance

Author: Aabid, Sami El, Institut National Polytechnique de Toulouse - Toulouse INP (FRANCE), and Institut National Polytechnique de Toulouse - INPT (FRANCE)
Subjects: Courbe de polarisation (V-I), Modélisation, Pile à combustible, Modèle dynamique, Impédance résiduelle, Identification paramétrique, PEMFC, Diagnostic, Spectros-copie d’Impédance Electrochimique (SIE), Modèle quasistatique
Abstract: Les piles à combustible se positionnent aujourd’hui comme une alternative technologique séduisante face aux solutions classiquement utilisées pour le stockage d’énergie. De par leur rendement de conversion en énergie électrique et leur haute densité énergétique, les grands acteurs du secteur aéronautique en voient une solution intéressante pour réduire l’impact environnemental des avions. C’est dans cette optique que s’inscrit la présente thèse, visant à contribuer au développement de méthodologies destinées au suivi de l’état de santé d’une pile à combustible à membrane échangeuse de protons (Proton Exchange Membrane Fuel Cell PEMFC). Il a été montré, dans un premier temps, que l’ensemble des constituants d’une pile était soumis à des contraintes pouvant engendrer des défaillances irréversibles ou des pertes de performances. Cette synthèse a permis de mettre en exergue la nécessité de disposer de méthodes de diagnostic permettant de suivre l’état de santé de la pile. Dans ce sens, des outils basés sur le principe de l’identification paramétrique ont été mis en avant. Il s’agit dans un premier temps de pouvoir, à partir de caractérisations expérimentales, être capable de mettre en œuvre une procédure appropriée permettant d’identifier les paramètres d’un modèle représentant au mieux le comportement du composant. Et dans un temps second, de construire par l’intermédiaire des paramètres identifiés des indicateurs (signatures) liés à l’état de santé de la pile. Dans le cadre de cette thèse, nous nous sommes intéressés plus particulièrement à deux types de prise d’informations : la courbe de polarisation (V-I), et la Spectroscopie d’Impédance Electrochimique (SIE). Il a été montré dans cette thèse, que seule l’exploitation conjointe de ces 2 types de mesures permet une caractérisation pertinente de l’état de santé de la pile. Deux modèles «couplés» ont été ainsi développés : un modèle quasi-statique dont les paramètres sont identifiés à partir de la courbe de polarisation et un modèle dynamique identifié à partir des données de la SIE. Il a été mis en avant dans le cadre de cette thèse, la nécessité de développer un modèle dynamique dit «sans a priori» dont la formulation peut varier au cours du temps. Ainsi, si des phénomènes liés à un changement de caractéristique apparaissent, la structure du modèle pourra s’adapter pour en permettre la prise en compte. Le processus global partant de la connaissance a priori jusqu’à l’identification des paramètres des modèles a été développé au cours des chapitres de cette thèse. Outre la bonne reproduction des données expérimentales et la séparation des pertes dans les domaines quasi-statique et dynamique, l’approche permet de percevoir certaines défaillances à travers les paramètres des modèles développés. La prise en compte du couplage statique-dynamique a fait apparaître la notion « d’impédance résiduelle ». En effet, un biais entre la pente locale de la courbe de polarisation et la résistance basse fréquence de la SIE est systématiquement observé. L’impédance résiduelle prise en compte dans la modélisation permet d’absorber ce décalage tout en garantissant une cohérence entre les mesures de la V-I et de la SIE. Une tentative d’explication des phénomènes physico-chimiques liés à cette impédance a également fait partie de l’ensemble des objectifs de cette thèse. D’un point de vue expérimental, l’idée du travail est dans un premier temps de générer des variations ciblées et maîtrisées du comportement de la pile et d’observer leurs impacts sur les paramètres identifiés. Pour ce faire, l’idée proposée est de travailler sur une mono-cellule dont la modification des composants est aisée. Le jeu de composants (membranes différentes, différents dosages en platine …) avait permis de mettre en évidence l’impact de chaque modification sur les données expérimentales et ainsi sur le modèle avant de tester la validité de l’approche sur des campagnes de vieillissement de stacks
Published: 2021
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26. Transmissions de l’exploitation en moyenne montagne pyrénéenne : ruptures et continuités

Author: Claire Manoli, Jean Philippe Choisis, Sylvie Ladet, Annick Gibon, Institut National Polytechnique de Toulouse - Toulouse INP (FRANCE), Institut National de la Recherche Agronomique - INRA (FRANCE), Ecole Supérieure d’Agricultures - ESA (FRANCE), Unité de Recherche sur les Systèmes d'Elevage, Université Bretagne Loire (UBL), Dynamiques Forestières dans l'Espace Rural (DYNAFOR), Institut National de la Recherche Agronomique (INRA)-École nationale supérieure agronomique de Toulouse [ENSAT]-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées, Financement du projet Trans (2007-2009) du programme « Agriculture et développement durable » et du projet Chapay (2008-2011) du programme PSDR INRA-Région Midi-Pyrénées, ANR-05-PADD-0003,TRANS,Transformations de l'élevage et dynamiques des espaces(2005), and Institut National Polytechnique de Toulouse - INPT (FRANCE)
Subjects: Pyrénées, 2. Zero hunger, Agronomie, Sciences et techniques de l'agriculture, [SDV]Life Sciences [q-bio], Biodiversité et Ecologie, transmission des exploitations, pyrénées, [SHS]Humanities and Social Sciences, Transmission des exploitations, Exploitation agricole, exploitation agricole, ComputingMilieux_MISCELLANEOUS
Abstract: Que transmet-on quand on transmet une exploitation agricole aujourd’hui? La pérennité des exploitations et la transmission intergénérationnelle sont au centre des enjeux du développement durable, en agriculture notamment (Landais, 1999)
Published: 2020
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27. Hyperspectral unmixing with spectral variability using adaptive bundles and double sparsity

Author: Nicolas Dobigeon, Tatsumi Uezato, Mathieu Fauvel, Ecole Nationale Supérieure d'Electrotechnique, d'Electronique, d'Informatique, d'Hydraulique et de Télécommunications (ENSEEIHT), Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées, Signal et Communications (IRIT-SC), Institut de recherche en informatique de Toulouse (IRIT), Université Toulouse 1 Capitole (UT1), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse - Jean Jaurès (UT2J)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse 1 Capitole (UT1), Université Fédérale Toulouse Midi-Pyrénées, Dynamiques Forestières dans l'Espace Rural (DYNAFOR), Institut National de la Recherche Agronomique (INRA)-École nationale supérieure agronomique de Toulouse [ENSAT]-Institut National Polytechnique (Toulouse) (Toulouse INP), European Union (EU), MapInvPlnt Project, MUESLI IDEX ATS Project, Toulouse INP, ANR-15-NMED-0002,MapInvPint,Monitoring the Water Hyacinth Using ASTER Imagery(2015), Ecole Nationale Supérieure d'Electrotechnique, d'Electronique, d'Informatique, d'Hydraulique et de Télécommunications ( ENSEEIHT ), Institut National Polytechnique [Toulouse] ( INP ) -Institut de recherche en informatique de Toulouse ( IRIT ), Institut National Polytechnique [Toulouse] ( INP ) -Université Toulouse 1 Capitole ( UT1 ) -Université Toulouse - Jean Jaurès ( UT2J ) -Université Paul Sabatier - Toulouse 3 ( UPS ) -Centre National de la Recherche Scientifique ( CNRS ) -Université Toulouse 1 Capitole ( UT1 ) -Université Toulouse - Jean Jaurès ( UT2J ) -Université Paul Sabatier - Toulouse 3 ( UPS ) -Centre National de la Recherche Scientifique ( CNRS ), Centre National d'Études Spatiales - CNES (FRANCE), Centre National de la Recherche Scientifique - CNRS (FRANCE), Institut National Polytechnique de Toulouse - Toulouse INP (FRANCE), Institut National de la Recherche Agronomique - INRA (FRANCE), Institut de Recherche pour le Développement - IRD (FRANCE), Université Toulouse III - Paul Sabatier - UT3 (FRANCE), Université Toulouse - Jean Jaurès - UT2J (FRANCE), Université Toulouse 1 Capitole - UT1 (FRANCE), and Institut National Polytechnique de Toulouse - INPT (FRANCE)
Subjects: FOS: Computer and information sciences, [SPI.OTHER]Engineering Sciences [physics]/Other, Endmember, Hyperspectral imaging, Computer science, 0211 other engineering and technologies, FOS: Physical sciences, Machine Learning (stat.ML), 02 engineering and technology, [ PHYS.PHYS.PHYS-DATA-AN ] Physics [physics]/Physics [physics]/Data Analysis, Statistics and Probability [physics.data-an], Spectral line, Image (mathematics), Statistics::Machine Learning, Endmember variability, Statistics - Machine Learning, Component (UML), FOS: Electrical engineering, electronic engineering, information engineering, Traitement du signal et de l'image, Electrical and Electronic Engineering, 021101 geological & geomatics engineering, [PHYS]Physics [physics], Sparse unmixing, [ PHYS ] Physics [physics], Spectral signature, Pixel, business.industry, Image and Video Processing (eess.IV), Informatique et langage, Pattern recognition, Electrical Engineering and Systems Science - Image and Video Processing, Apprentissage, Physics - Data Analysis, Statistics and Probability, Computer Science::Computer Vision and Pattern Recognition, General Earth and Planetary Sciences, Artificial intelligence, business, Spectral unmixing, Data Analysis, Statistics and Probability (physics.data-an), [PHYS.PHYS.PHYS-DATA-AN]Physics [physics]/Physics [physics]/Data Analysis, Statistics and Probability [physics.data-an]
Abstract: International audience; Spectral variability is one of the major issue when conducting hyperspectral unmixing. Within a given image composed of some elementary materials (herein referred to as endmember classes), the spectral signature characterizing these classes may spatially vary due to intrinsic component fluctuations or external factors (illumination). These redundant multiple endmember spectra within each class adversely affect the performance of unmixing methods. This paper proposes a mixing model that explicitly incorporates a hierarchical structure of redundant multiple spectra representing each class. The proposed method is designed to promote sparsity on the selection of both spectra and classes within each pixel. The resulting unmixing algorithm is able to adaptively recover several bundles of endmember spectra associated with each class and robustly estimate abundances. In addition, its flexibility allows a variable number of classes to be present within each pixel of the hyperspectral image to be unmixed. The proposed method is compared with other state-of-the-art unmixing methods that incorporate sparsity using both simulated and real hyperspectral data. The results show that the proposed method can successfully determine the variable number of classes present within each class and estimate the corresponding class abundances.
Published: 2020
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28. Direct numerical simulations of droplet condensation

Author: Annagrazia Orazzo, Sébastien Tanguy, Centre National de la Recherche Scientifique - CNRS (FRANCE), Institut National Polytechnique de Toulouse - INPT (FRANCE), Université Toulouse III - Paul Sabatier - UT3 (FRANCE), Institut de mécanique des fluides de Toulouse (IMFT), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées, and Institut National Polytechnique de Toulouse - Toulouse INP (FRANCE)
Subjects: Drag coefficient, Work (thermodynamics), Materials science, Mécanique des fluides, 02 engineering and technology, Direct numerical simulations, 01 natural sciences, Isothermal process, [SPI.MECA.MEFL]Engineering Sciences [physics]/Mechanics [physics.med-ph]/Fluids mechanics [physics.class-ph], 010305 fluids & plasmas, Physics::Fluid Dynamics, Heat transfer, 0103 physical sciences, Droplets condensation, Phase change, Two-phase flows, Condensed Matter::Quantum Gases, Fluid Flow and Transfer Processes, Condensed Matter::Other, Mechanical Engineering, Condensation, Mechanics, 021001 nanoscience & nanotechnology, Condensed Matter Physics, Nusselt number, Subcooling, Heat flux, 0210 nano-technology
Abstract: International audience; We present in this work well-resolved and accurate Direct Numerical Simulations (DNS) of droplet condensation. Despite the great scientific and industrial interest, to this day, there is not an extensive knowledge of the different processes involved in droplet condensation. Consequently, DNS should be considered as a promising tool to investigate on this phenomenon. A preliminary validation of our simulations is carried out by direct comparison with the quasi-static theory of the droplet condensation in an infinite vapour medium. Next, more complex configurations have been considered: the condensation of a moving droplet in a subcooled vapour flow and the condensation of a hemispherical droplet deposed on an isothermal flat surface. The latter represents a first step towards the understanding of the more demanding DropWise Condensation. In both configurations, the effects of the Jakob number, Ja, have been thoroughly analysed to understand how the condensation impacts on the droplet heat flux and dynamics. This has led to the definition of a particular condensation regime for the lower Ja values, hereinafter called low condensation rate regime, where the droplet heat transfer is independent of the Ja. By increasing the Ja, instead, the effects due to condensation start to grow exponentially. This regime is referred as the high condensation rate regime in this paper. Finally, some general trends for correlations on the Nusselt number and drag coefficient accounting for condensation are proposed in this study.
Published: 2019
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29. Evaluation of the protectiveness of an organosilane coating on patinated Cu-Si-Mn bronze for contemporary art

Author: Cristina Chiavari, Tadeja Kosec, Luc Robbiola, E. Svara Fabjan, Jérôme Esvan, F. Zanotto, Andrea Balbo, Claudie Josse, Elena Bernardi, Carla Martini, Maria Chiara Bignozzi, Cecilia Monticelli, Giulia Masi, Masi, G., Josse, C., Esvan, J., Chiavari, C., Bernardi, E., Martini, C., Bignozzi, M.C., Monticelli, C., Zanotto, F., Balbo, A., Svara Fabjan, E., Kosec, T., Robbiola, L., Centre National de la Recherche Scientifique - CNRS (FRANCE), Institut National Polytechnique de Toulouse - Toulouse INP (FRANCE), Institut National des Sciences Appliquées de Toulouse - INSA (FRANCE), Università di Bologna (ITALY), Université Toulouse III - Paul Sabatier - UT3 (FRANCE), Université Toulouse - Jean Jaurès - UT2J (FRANCE), Slovenian national building and civil engineering institute -ZAG (SLOVENIA), Ministère de la culture et de la communication (FRANCE), Università degli Studi di Ferrara - UNIFE (ITALY), Centre de microcaractérisation Raimond Castaing (Toulouse, France), Travaux et Recherches Archéologiques sur les Cultures, les Espaces et les Sociétés - TRACES (Toulouse, France), Institut National Polytechnique de Toulouse - INPT (FRANCE), Alma Mater Studiorum Università di Bologna [Bologna] (UNIBO), Centre de microcaractérisation Raimond Castaing (CMCR), Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), 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)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées, Centre interuniversitaire de recherche et d'ingenierie des matériaux (CIRIMAT), Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC), Università degli Studi di Ferrara (UniFE), Zavod za gradbeništvo Slovenije [Ljubljana] (ZAG), Zavod za gradbeništvo Slovenije, Travaux et recherches archéologiques sur les cultures, les espaces et les sociétés (TRACES), École des hautes études en sciences sociales (EHESS)-Université Toulouse - Jean Jaurès (UT2J)-Ministère de la Culture et de la Communication (MCC)-Centre National de la Recherche Scientifique (CNRS), Centre de microcaractérisation Raimond Castaing (Centre Castaing), 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), Université de Toulouse (UT)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Università degli Studi di Ferrara = University of Ferrara (UniFE), École des hautes études en sciences sociales (EHESS)-Université Toulouse - Jean Jaurès (UT2J), and Université de Toulouse (UT)-Université de Toulouse (UT)-Ministère de la Culture et de la Communication (MCC)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Materials science, Matériaux, General Chemical Engineering, Alloy, Oxide, chemistry.chemical_element, 02 engineering and technology, engineering.material, 010402 general chemistry, 01 natural sciences, Corrosion, Electrochemical technique, chemistry.chemical_compound, Coating, Organic coating, XPS, Materials Chemistry, Bronze, UV degradation, Organic Chemistry, Metallurgy, Ambientale, [CHIM.MATE]Chemical Sciences/Material chemistry, 021001 nanoscience & nanotechnology, Copper, 0104 chemical sciences, Surfaces, Coatings and Films, chemistry, 13. Climate action, engineering, Electrochemical techniques, Atmospheric corrosion, 0210 nano-technology, Layer (electronics)
Abstract: International audience; A 3-mercapto-propyl-trimethoxysilane coating (PropS-SH) applied on Cu-Si-Mn bronze, patinated by “liver of sulphur”, was investigated as a non-toxic alternative to Incralac®, usually applied on outdoor artistic bronzes. Electrochemical testing was performed in synthetic acid rain. Exposure to temperature/UV cycles and accelerated corrosion test simulating unsheltered exposure to rainwater was also carried out. The exposed samples were characterised by FEG-SEM coupled with EDS on FIB cross-sections and XPS on free surfaces. The black patina without protective coating was scarcely protective against bronze corrosion and easily transformed into cuprous oxide. PropS-SH coating fully preserved the black patina microstructure and phase constituents (cuprous oxide and cuprous sulphide). The PropS-SH coating also resulted more protective than Incralac® when aged under run-off conditions. Selective dissolution of copper from the silicon bronze alloy was observed on both uncoated and Incralac®-coated bronze, leading to the formation of an internal Si-rich corrosion layer.
Published: 2019
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30. Chemiluminescence based operating point control of domestic gas boilers with variable natural gas composition

Author: Daniel Durox, Yi Ding, Nasser Darabiha, Thierry Schuller, Centre National de la Recherche Scientifique - CNRS (FRANCE), Institut National Polytechnique de Toulouse - INPT (FRANCE), Université Paris-Saclay (FRANCE), Université Toulouse III - Paul Sabatier - UT3 (FRANCE), Bosch Thermotechnologie (FRANCE), CentraleSupélec (FRANCE), Institut de Mécanique des Fluides de Toulouse - IMFT (Toulouse, France), Laboratoire d'Énergétique Moléculaire et Macroscopique, Combustion (EM2C), Université Paris Saclay (COmUE)-Centre National de la Recherche Scientifique (CNRS)-CentraleSupélec, Institut de mécanique des fluides de Toulouse (IMFT), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées, and Institut National Polytechnique de Toulouse - Toulouse INP (FRANCE)
Subjects: Equivalence ratio regulation, Hydrogen, Mécanique des fluides, 020209 energy, Biogas, Energy Engineering and Power Technology, chemistry.chemical_element, 02 engineering and technology, Combustion, 7. Clean energy, Industrial and Manufacturing Engineering, 020401 chemical engineering, Natural gas, 0202 electrical engineering, electronic engineering, information engineering, [PHYS.MECA.MEFL]Physics [physics]/Mechanics [physics]/Fluid mechanics [physics.class-ph], Flame chemiluminescence, Gas composition, 0204 chemical engineering, Process engineering, Operating point, business.industry, chemistry, 13. Climate action, Domestic gas boiler, Combustor, Environmental science, business, Intensity (heat transfer)
Abstract: International audience; The current control strategy of domestic gas boilers optimizes the heating efficiency and pollutant gas emissions assuming a fixed fuel composition. However, larger and more frequent variations of gas composition are ex- pected in the European natural gas network. New control systems capable of monitoring and regulating the flame equivalence ratio in real time are therefore necessary. The present work investigates one equivalence ratio sensing strategy by analyzing the flame chemiluminescence signal from a laminar premixed burner widely used in domestic gas boilers. The OH∗ chemiluminescence intensity is first identified as a reliable equivalence ratio indicator, valid for different natural gas composition scenarios with CH4 diluted by N2 or CO2 or enriched by H2, C2H6 or C3H8. These fuel mixtures are representative of biogas and hydrogen enriched natural gas. A demonstrative control loop is developed based on the OH∗ signal measured by a photomultiplier tube mounted with a bandpass optical filter. The system is tested by changing the equivalence ratio set value and the fuel composition. It is shown to be capable of regulating the equivalence ratio of these natural gas fuel blends with a good precision. The differences observed between the real and target values for the equivalence ratio are in most cases lower than 0.01. Only fuel blends with C3H8 lead to slightly larger errors of 0.03.
Published: 2019
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31. Influence of consolidation process on voids and mechanical properties of powdered and commingled carbon/PPS laminates

Author: Julien Patou, Rébecca Bonnaire, Emmanuel De Luycker, Gérard Bernhart, Centre National de la Recherche Scientifique - CNRS (FRANCE), Ecole nationale supérieure des Mines d'Albi-Carmaux - IMT Mines Albi (FRANCE), Institut National Polytechnique de Toulouse - Toulouse INP (FRANCE), Institut National des Sciences Appliquées de Toulouse - INSA (FRANCE), Institut Supérieur de l'Aéronautique et de l'Espace - ISAE-SUPAERO (FRANCE), Université Toulouse III - Paul Sabatier - UT3 (FRANCE), Institut National Polytechnique de Toulouse - INPT (FRANCE), Institut Clément Ader (ICA), Institut Supérieur de l'Aéronautique et de l'Espace (ISAE-SUPAERO)-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), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-IMT École nationale supérieure des Mines d'Albi-Carmaux (IMT Mines Albi), Institut Mines-Télécom [Paris] (IMT)-Institut Mines-Télécom [Paris] (IMT), Laboratoire Génie de Production (LGP), Ecole Nationale d'Ingénieurs de Tarbes (ENIT), Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Université de Toulouse (UT), Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-IMT École nationale supérieure des Mines d'Albi-Carmaux (IMT Mines Albi), Institut Mines-Télécom [Paris] (IMT)-Institut Mines-Télécom [Paris] (IMT)-Institut Supérieur de l'Aéronautique et de l'Espace (ISAE-SUPAERO), and Ecole Nationale d'Ingénieurs de Tarbes
Subjects: Void (astronomy), Materials science, Carbon fibers, Consolidation process, Mechanical properties, 02 engineering and technology, 010402 general chemistry, 01 natural sciences, [SPI]Engineering Sciences [physics], Ultimate tensile strength, Composite material, Porosity, Consolidation (soil), Thermoplastic resin, Microstructural analysis, 021001 nanoscience & nanotechnology, Microstructure, 0104 chemical sciences, Mechanics of Materials, visual_art, Ceramics and Composites, visual_art.visual_art_medium, Mécanique des matériaux, Vacuum level, 0210 nano-technology, Consolidation
Abstract: Relations between autoclave consolidation process, microstructure and mechanical properties of thermoplastic composite laminates were investigated. For this purpose, two different carbon fibers/PPS semi-pregs were used for laminate manufacturing: a powdered fabric and a commingled fabric with stretch broken fibers. Laminates with [ 0 ° ] 6 stacking sequence were consolidated in autoclave. Several consolidation levels were established by varying process parameters which are external pressure, vacuum level and consolidation duration. Microstructural characterization was performed by using matrix digestion and CT-scanning to identify void content and morphology. Laminate mechanical properties in tensile, bending, compressive and interlaminar shear were also assessed. External pressure increase by 0.5 MPa leads to void content reduction of 2.1% for powdered system and 5.4 % for commingled system. The rising consolidation duration contributes slightly to void content decrease. Bending and interlaminar failure stress are the most sensitive to void level with a dependency on void size and location. Results acquired allow to identify main settings for optimized consolidation cycles which could be used for thermoplastic composite part manufacturing with complex shape.
Published: 2019
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32. Yield enhancement strategy of dithiolopyrrolone from Saccharothrix algeriensis by aliphatic alcohols supplementation

Author: Geneviève Baziard, Alaa Hamdar, Barbora Lajoie, Christine Roques, Fatima El Garah, Salomé El Hage, Centre National de la Recherche Scientifique - CNRS (FRANCE), Institut National Polytechnique de Toulouse - Toulouse INP (FRANCE), Université Toulouse III - Paul Sabatier - UT3 (FRANCE), Institut National Polytechnique de Toulouse - INPT (FRANCE), Laboratoire de Génie Chimique (LGC), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), and Université Fédérale Toulouse Midi-Pyrénées
Subjects: Alcohols addition, [SDV]Life Sciences [q-bio], Bioengineering, Saccharothrix algeriensis, Applied Microbiology and Biotechnology, Biochemistry, Scavenger, 03 medical and health sciences, chemistry.chemical_compound, Génie chimique, Food science, Génie des procédés, Overproduction, 030304 developmental biology, chemistry.chemical_classification, 0303 health sciences, Reactive oxygen species, Oxidase test, Ethanol, 030306 microbiology, Dithiolopyrrolones, chemistry, Yield (chemistry), NAD+ kinase
Abstract: Description of the relationship between protein structure and function remains a primary focus in molecular biology, biochemistry, protein engineering and bioelectronics. Moreover, the investigation of the protein conformational changes after adhesion and dehydration is of importance to tackle problems related to the interaction of proteins with solid surfaces. In this paper the conformational changes of wild-type Discosoma recombinant red fluorescent proteins (DsRed) adhered on silver nanoparticles (AgNPs)-based nanocomposites are explored via surface-enhanced Raman scattering (SERS). Originality in the present approach is to work on dehydrated DsRed thin protein layers in link with natural conditions during drying. To enable the SERS effect, plasmonic substrates consisting of a single layer of AgNPs encapsulated by an ultra-thin silica cover layer were elaborated by plasma process. The achieved enhancement of the electromagnetic field in the vicinity of the AgNPs is as high as 105. This very strong enhancement factor allowed detecting Raman signals from discontinuous layers of DsRed issued from solution with protein concentration of only 80 nM. Three different conformations of the DsRed proteins after adhesion and dehydration on the plasmonic substrates were identified. It was found that the DsRed chromophore structure of the adsorbed proteins undergoes optically assisted chemical transformations when interacting with the optical beam, which leads to reversible transitions between the three different conformations. The proposed time-evolution scenario endorses the dynamical character of the relationship between protein structure and function. It also confirms that the conformational changes of proteins with strong internal coherence, like DsRed proteins, are reversible.
Published: 2019
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33. Experimental pressure versus temperature isochoric – isoplethic curves for n-pentane – dimethyl ether, n-pentane – dimethyl ether – polybutadiene and n-pentane – dimethyl ether – polybutadiene– hydrogen at high pressures

Author: Juan M. Milanesio, Andrés Eduardo Ciolino, Matías Menossi, Marcelo S. Zabaloy, Séverine Camy, Instituto de Investigación y Desarrollo en Ingeniería de Procesos y Química Aplicada (IPQA), Universidad Nacional de Cordoba, Planta Piloto de Ingeniería Química [Bahía Blanca] (PLAPIQUI), Universidad Nacional del Sur [Argentina] (UNS)-Consejo Nacional de Investigaciones Científicas y Técnicas [Buenos Aires] (CONICET), Laboratoire de génie chimique [ancien site de Basso-Cambo] (LGC), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées, Centre National de la Recherche Scientifique - CNRS (FRANCE), Institut National Polytechnique de Toulouse - Toulouse INP (FRANCE), Universidad Nacional de Cordoba - UNC (ARGENTINA), Universidad Nacional del Sur - UNS (ARGENTINA), Université Toulouse III - Paul Sabatier - UT3 (FRANCE), and Institut National Polytechnique de Toulouse - INPT (FRANCE)
Subjects: Hydrogen, General Chemical Engineering, Analytical chemistry, chemistry.chemical_element, 02 engineering and technology, chemistry.chemical_compound, Polybutadiene, [CHIM.GENI]Chemical Sciences/Chemical engineering, 020401 chemical engineering, n-Pentane, Génie chimique, Dimethyl ether, Isochoric/isoplethic loci, 0204 chemical engineering, Physical and Theoretical Chemistry, Chemistry, Isochoric process, 021001 nanoscience & nanotechnology, Condensed Matter Physics, Solvent, Pentane, PC-SAFT EoS, 0210 nano-technology, Ternary operation, Mass fraction
Abstract: International audience; Loci of isochoric - isoplethic experimental phase equilibrium data, were determined for the binary mixture dimethyl ether (DME) + n-pentane (C5); the ternary mixture: DME + C5 + polybutadiene (PB); and the quaternary mixture DME + C5 + PB + hydrogen (H2). Binary experiments were performed at varying overall density (ρ) and varying quantity of C5. Ternary experiments were performed at varying ρ and varying relative quantities of each light solvent. In the case of quaternary mixtures, the mass fraction of polymer was kept constant, and the amount of H2 and ρ were varied. The experimental data obtained for binary and ternary mixtures were correlated using the Perturbed-Chain Statistical Associating Fluid Theory (PC-SAFT) equation of state (EoS).
Published: 2020
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34. Application of fuzzy theory for identifying the required availability of an autonomous localization unit in European Train Control System

Author: Juliette Marais, Marion Berbineau, Julie Beugin, Khanh T. P. Nguyen, Ecole Nationale d'Ingénieurs de Tarbes (ENIT), Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées, Évaluation des Systèmes de Transports Automatisés et de leur Sécurité (IFSTTAR/COSYS/ESTAS), Institut Français des Sciences et Technologies des Transports, de l'Aménagement et des Réseaux (IFSTTAR)-PRES Université Lille Nord de France, Département Composants et Systèmes (IFSTTAR/COSYS), PRES Université Lille Nord de France-PRES Université Nantes Angers Le Mans (UNAM)-Université de Lyon-Institut Français des Sciences et Technologies des Transports, de l'Aménagement et des Réseaux (IFSTTAR), Laboratoire Électronique Ondes et Signaux pour les Transports (IFSTTAR/COSYS/LEOST), Institut Français des Sciences et Technologies des Transports, de l'Aménagement et des Réseaux - IFSTTAR (FRANCE), Institut National Polytechnique de Toulouse - Toulouse INP (FRANCE), Université de Lille (FRANCE), and Institut National Polytechnique de Toulouse - INPT (FRANCE)
Subjects: Fuzzy sets, HIGH-SPEED RAIL, Computer science, Fuzzy set, Intelligent control system, Aerospace Engineering, System availability, 02 engineering and technology, Fuzzy logic, SYSTEME DE TRANSPORT INTELLIGENT, [SPI.AUTO]Engineering Sciences [physics]/Automatic, European Train Control System, LOCALISATION, Autre, SURETE DE FONCTIONNEMENT, SYSTEME INTELLIGENT, 0502 economics and business, 0202 electrical engineering, electronic engineering, information engineering, Dependability, GRANDE VITESSE, AIDE A LA DECISION, SECURITE, TRAIN A GRANDE VITESSE - TGV, Fault tree analysis, 050210 logistics & transportation, Applied Mathematics, High-speed rail, 05 social sciences, SYSTEM AVAILABILITY, Computer Science Applications, Reliability engineering, System requirements, TRANSPORT FERROVIAIRE, INTELLIGENT CONTROL SYSTEM, Control and Systems Engineering, Automotive Engineering, VOIE FERREE, 020201 artificial intelligence & image processing, Unavailability, FUZZY SETS, Software, Membership function, Information Systems
Abstract: According to the evolution tendency of the control decision process from a trackside to a train-borne system, various autonomous localization units for railway vehicles were developed. As recommended in railway standards, the design process of each system, here the autonomous localization units (LU), follows the V-model whose first step is to define its availability requirement in order to satisfy the global ETCS system requirements. The classical approach for assigning the subsystem availability is based on the assumption that failure parameters of other units are precisely known. This assumption is too restricted in reality due to the lack of information. In this paper, we propose a new approach that allows taking into account uncertainties in the dependability parameters of the ETCS components for identifying the upper threshold of the LU unavailability to reach ETCS availability requirements. Using fuzzy fault trees, the fuzzy unavailability of the ETCS without the autonomous LU is evaluated. Then, based on its membership function, we assess the satisfaction rate that an advanced ETCS with the autonomous LU can satisfy the ETCS availability target.
Published: 2019
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35. Design and control of pressure-swing distillation for separating ternary systems with three binary minimum azeotropes

Author: Jie Li, Shun an Wei, Vincent Gerbaud, Ao Yang, Weifang Shen, Lichun Dong, Centre National de la Recherche Scientifique - CNRS (FRANCE), Chongqing University (CHINA), Institut National Polytechnique de Toulouse - Toulouse INP (FRANCE), Université Toulouse III - Paul Sabatier - UT3 (FRANCE), University of Manchester (UNITED KINGDOM), Laboratoire de Génie Chimique - LGC (Toulouse, France), Chongqing University [Chongqing], University of Manchester [Manchester], Laboratoire de génie chimique [ancien site de Basso-Cambo] (LGC), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées, and Institut National Polytechnique de Toulouse - INPT (FRANCE)
Subjects: Optimization, Environmental Engineering, Materials science, General Chemical Engineering, Boundary (topology), Binary number, triple-column pressure-swing distillation, 02 engineering and technology, law.invention, chemistry.chemical_compound, [CHIM.GENI]Chemical Sciences/Chemical engineering, 020401 chemical engineering, law, Génie chimique, [SPI.GPROC]Engineering Sciences [physics]/Chemical and Process Engineering, Temperature difference control strategy, 0204 chemical engineering, Génie des procédés, Triple‐column pressure‐swing distillation, Process engineering, Distillation, Tetrahydrofuran, Ternary numeral system, business.industry, Residue curve, residue curve maps, Swing, 021001 nanoscience & nanotechnology, chemistry, Ternary system, 0210 nano-technology, Ternary operation, business, Biotechnology
Abstract: International audience; The separation of ternary nonideal systems with multi‐azeotrope is very important because they are often found in the waste of chemical and pharmaceutical industries, which is much more difficult due to the formation of multi‐azeotrope and distillation boundary. We propose a systematic procedure for design and control of a triple‐column pressure‐swing distillation for separating ternary systems with three binary minimum azeotropes. This procedure involves thermodynamic insights, a two‐step optimization method, and effective control strategy. The separation of tetrahydrofuran (THF)/ethanol/water is used to illustrate the capability of the proposed procedure. It is found that the pressure limits in columns can be determined through the analysis of residue curve maps, distillation boundary, and isovolatility curves. The optimal triple‐column pressure‐swing distillation is generated with the minimum total annual cost (TAC) of $2.181 × 106 in sequence A. The operating conditions are well controlled approaching their desired specifications in an acceptable time when disturbances occur.
Published: 2019
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36. Experimental and Numerical Investigation of the Response of a Swirled Flame to Flow Modulations in a Non-Adiabatic Combustor

Author: Adrien Chatelier, Thierry Schuller, Thibault F. Guiberti, Renaud Mercier, Benoit Fiorina, Nicolas Bertier, Centre National de la Recherche Scientifique - CNRS (FRANCE), Institut National Polytechnique de Toulouse - INPT (FRANCE), King Abdullah University of Science and Technology - KAUST (SAUDI ARABIA), Office National d'Etudes et Recherches Aérospatiales - ONERA (FRANCE), Université Toulouse III - Paul Sabatier - UT3 (FRANCE), SAFRAN (FRANCE), Institut de Mécanique des Fluides de Toulouse - IMFT (Toulouse, France), Laboratoire d'Énergétique Moléculaire et Macroscopique, Combustion (EM2C), Université Paris Saclay (COmUE)-Centre National de la Recherche Scientifique (CNRS)-CentraleSupélec, DMPE, ONERA, Université Paris Saclay (COmUE) [Châtillon], ONERA-Université Paris Saclay (COmUE), King Abdullah University of Science and Technology (KAUST), SAFRAN Group, Institut de mécanique des fluides de Toulouse (IMFT), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées, and Institut National Polytechnique de Toulouse - Toulouse INP (FRANCE)
Subjects: Work (thermodynamics), Swirling flames, Computer science, Mécanique des fluides, 020209 energy, General Chemical Engineering, Flame transfer function, General Physics and Astronomy, 02 engineering and technology, 01 natural sciences, 010305 fluids & plasmas, Turbulent premixed combustion, 0103 physical sciences, 0202 electrical engineering, electronic engineering, information engineering, [PHYS.MECA.MEFL]Physics [physics]/Mechanics [physics]/Fluid mechanics [physics.class-ph], Non-adiabatic combustion, Physical and Theoretical Chemistry, Aerospace engineering, Adiabatic process, business.industry, Flame dynamics, Flow (mathematics), Combustor, Christian ministry, business, Flow solver
Abstract: International audience; Turbulent combustion models for Large Eddy Simulation (LES) aims at predicting the flame dynamics. So far, they have been proven to predict correctly the mean flow and flame properties in a wide range of configurations. A way to challenge these models in unsteady situations is to test their ability to recover turbulent flames submitted to harmonic flow modulations. In this study, the Flame Transfer Function (FTF) of a CH4/H2/air premixed swirled-stabilized flame submitted to harmonic flowrate modulations in a non-adiabatic combustor is compared to the response computed using the Filtered TAbulated Chemistry for LES (F-TACLES) formalism. Phase averaged analysis of the perturbed flow field and flame response reveal that the velocity field determined with Particle Image Velocimetry measurements, the heat release distribution inferred from OH* images and the probability of presence of burnt gases deduced from OH-Planar Laser Induced Fluorescence measure- ments are qualitatively well reproduced by the simulations. However, noticeable differences between experiments and simulations are also observed in a narrow frequency range. A detailed close-up view of the flow field highlight differences in experimental OH* and numerical volumetric heat release rate distributions which are at the origin of the differences observed between the numerical and experimental FTF. These differences mainly originate from the outer shear layer of the swirling jet where a residual reaction layer takes place in the simulations which is absent in the experiments. Consequences for turbulent combustion modeling are suggested by examining the evolution of the perturbed flame brush envelope along the downstream distance of the perturbed flames. It is shown that changing the grid resolution and the flame subgrid scale wrinkling factor in these regions does not alter the numerical results. It is finally concluded that the combined effects of strain rate and enthalpy defect due to heat losses are the main factors leading to small but sizable differences of the flame response to coherent structures synchronized by the acoustic forcing in the outer shear layer of the swirling flow. These small differences in flame response lead in turn to a misprediction of the FTF at specific forcing frequencies.
Published: 2019
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37. Influence of the crystal structure of Ag2CO3 on the photocatalytic activity under visible light of Ag2CO3-Palygorskite nanocomposite material

Author: M'barek Amjoud, Lahcen Daoudi, Omar Lakbita, Francis Maury, Benaïssa Rhouta, François Senocq, Laboratoire de Matière Condensée et Nanostructures (LMCN), Faculté des Sciences et Techniques Gueliz-Université Cadi Ayyad [Marrakech] (UCA), Centre interuniversitaire de recherche et d'ingenierie des matériaux (CIRIMAT), Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC), Laboratoire de Géosciences et Géoenvironnement (LGG), Centre National de la Recherche Scientifique - CNRS (FRANCE), Institut National Polytechnique de Toulouse - INPT (FRANCE), Université Toulouse III - Paul Sabatier - UT3 (FRANCE), University of Cadi Ayyad - UCAM (MOROCCO), and Institut National Polytechnique de Toulouse - Toulouse INP (FRANCE)
Subjects: Materials science, Matériaux, Composite number, Metastable hexagonal β-Ag2CO3, General Physics and Astronomy, Monoclinic Ag2CO3, 02 engineering and technology, Crystal structure, 010402 general chemistry, 01 natural sciences, [SPI.MAT]Engineering Sciences [physics]/Materials, Palygorskite, chemistry.chemical_compound, medicine, Orange G, Ag2CO3, Nanocomposite, Surfaces and Interfaces, General Chemistry, 021001 nanoscience & nanotechnology, Condensed Matter Physics, 0104 chemical sciences, Surfaces, Coatings and Films, chemistry, Chemical engineering, Visible photocatalysis, Photocatalysis, 0210 nano-technology, medicine.drug, Monoclinic crystal system, Visible spectrum
Abstract: International audience; In a companion paper, it has been demonstrated the remarkably beneficial effect of palygorskite clay (Pal) fibers as support material coupled to appropriate thermal treatments and aging under CO2 atmosphere in monitoring the phase composition of Ag2CO3-Pal composite. In this new nanocomposite material, the structure of the functional component Ag2CO3 can be controlled from 100% stable monoclinic (m) to 100% metastable hexagonal β through an adjusted mixture of m- and β-Ag2CO3. The present study deals with the assessment of the visible photocatalytic properties of these various nanocomposite materials towards the removal of Orange G dye from aqueous solutions. It was found that the Ag2CO3-Pal nanocomposite in which Ag2CO3 was single-phased and crystallized with the stable monoclinic structure was more active than the one crystallizing entirely with the metastable β-Ag2CO3 structure. Nevertheless, the composite material containing a mixture of both Ag2CO3 phases with a relative content of 32% of β- and 68% of m-phase was found to be the most photoactive compound of the series. This behavior reveals likely a synergetic effect between both phases in the photocatalytic degradation of the dye under visible light.
Published: 2019
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38. Nutritive value and physical and chemical deterrents of forage grass litter explain feeding performances of two soil macrodetritivores

Author: Cécile Trân, Antoine Lecerf, Eric Chauvet, Claire Jouany, Mickaël Hedde, Christophe Laplanche, Benjamin Pey, Johanne Nahmani, P. Cruz, Laboratoire Sols et Environnement (LSE), Institut National de la Recherche Agronomique (INRA)-Université de Lorraine (UL), AGroécologie, Innovations, teRritoires (AGIR), Institut National de la Recherche Agronomique (INRA)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées, PESSAC, Institut National de la Recherche Agronomique (INRA), Laboratoire Ecologie Fonctionnelle et Environnement (ECOLAB), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Observatoire Midi-Pyrénées (OMP), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées, Centre d’Ecologie Fonctionnelle et Evolutive (CEFE), Institut de Recherche pour le Développement (IRD [France-Sud])-Centre National de la Recherche Scientifique (CNRS)-École pratique des hautes études (EPHE)-Université de Montpellier (UM)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro)-Institut National de la Recherche Agronomique (INRA)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Université Paul-Valéry - Montpellier 3 (UM3), Laboratoire Dynamique de la Biodiversité (LADYBIO), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS), Ecologie fonctionnelle et biogéochimie des sols et des agro-écosystèmes (UMR Eco&Sols), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut de Recherche pour le Développement (IRD)-Institut National de la Recherche Agronomique (INRA)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut Ecologie et Environnement (INEE), Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-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)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-École pratique des hautes études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Institut National de la Recherche Agronomique (INRA)-Université Paul-Valéry - Montpellier 3 (UPVM)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut de Recherche pour le Développement (IRD [France-Sud]), Centre de Coopération Internationale en Recherche Agronomique - CIRAD (FRANCE), Centre National de la Recherche Scientifique - CNRS (FRANCE), Institut National Polytechnique de Toulouse - Toulouse INP (FRANCE), Institut National de la Recherche Agronomique - INRA (FRANCE), Institut de Recherche pour le Développement - IRD (FRANCE), Université Toulouse III - Paul Sabatier - UT3 (FRANCE), Université de Toulouse (UT)-Université de Toulouse (UT), Laboratoire Ecologie Fonctionnelle et Environnement (LEFE), Institut Ecologie et Environnement (INEE), Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-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)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT), Université Paul-Valéry - Montpellier 3 (UPVM)-Institut National de la Recherche Agronomique (INRA)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-École Pratique des Hautes Études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD [France-Sud])-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Université de Toulouse (UT)-Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS), and Institut National Polytechnique de Toulouse - INPT (FRANCE)
Subjects: 0106 biological sciences, Litter (animal), Consumption, Perennial plant, forage grass litter, Biodiversité et Ecologie, Forage grass litte, Soil Science, 01 natural sciences, Glomeris marginata, ComputingMilieux_MISCELLANEOUS, Holcus lanatus, Bromus erectus, 2. Zero hunger, Armadillidium vulgare, assimilation, Ecology, biology, 04 agricultural and veterinary sciences, 15. Life on land, biology.organism_classification, Agricultural and Biological Sciences (miscellaneous), Functional trait, Agronomy, Assimilation, Brachypodium pinnatum, 040103 agronomy & agriculture, 0401 agriculture, forestry, and fisheries, Soil macrodetritivore, [SDE.BE]Environmental Sciences/Biodiversity and Ecology, Festuca rubra, 010606 plant biology & botany
Abstract: International audience; Millipedes (Diplopoda) and terrestrial isopods (Isopoda) may play a significant role in soil decomposition. The present study aimed to contribute to the general understanding of feeding performances of macrodetritivores consuming grass litter by answering two questions. Q1: Are grass litter traits indicating nutritive value (i.e. chemical) and traits indicating feeding deterrents (i.e. mainly physical but not necessarily) both necessary to explain individual feeding performances of soil invertebrates consuming grass litter? Q2: Do grass physical traits indicating physical deterrents (e.g. WHC for mechanical aspects) provide more than, less than or the same amount of information about invertebrate individual performances as grass chemical traits indicating mainly chemical but also physical deterrents (e.g. lignin content directly for digestibility and indirectly for mechanical aspects)? We thus designed a laboratory experiment to assess individual feeding performances of two common macrodetritivores (Armadillidium vulgare (Latreille, 1804) and Glomeris marginata (Villiers, 1789)) in four monospecific treatments of litter from perennial forage grasses (Brachypodium pinnatum P. Beauv., Bromus erectus Huds., Festuca rubra L. and Holcus lanatus L.). A. vulgare feeding performances were correlated with nutritive values (litter N and P contents) and plant mechanical aspects (LDMC: leaf dry matter content). G. marginata performances were correlated with chemical deterrents (cellulose and lignin contents). Thus, (Q1) for grass litters, both traits indicating nutritive value (e.g. N, P) and feeding deterrents (e.g. LDMC, lignin content) are necessary to explain macroinvertebrates feeding performances. We also demonstrated the results depend on the invertebrate species considered. Also, (Q2) chemical deterrents may influence feeding performances of G. marginata the most, while physical deterrents related to mechanical aspects may influence those of A. vulgare the most. Our study indicates that using grass chemical and physical traits that indicate both nutritive value and feeding deterrents can help explain feeding performances of macrodetritivores consuming grass litter.
Published: 2019
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39. A metrics-based approach to preparing sustainable membranes: application to ultrafiltration

Author: Ligia Barna, Flavie Prézélus, Christelle Guigui, Jean-Christophe Remigy, Dihia Chabni, Centre National de la Recherche Scientifique - CNRS (FRANCE), Institut National Polytechnique de Toulouse - INPT (FRANCE), Institut National de la Recherche Agronomique - INRA (FRANCE), Institut National des Sciences Appliquées de Toulouse - INSA (FRANCE), Université Toulouse III - Paul Sabatier - UT3 (FRANCE), Laboratoire de Génie Chimique (LGC), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées, Laboratoire d'Ingénierie des Systèmes Biologiques et des Procédés (LISBP), Centre National de la Recherche Scientifique (CNRS)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Institut National de la Recherche Agronomique (INRA), Institut National de la Recherche Agronomique (INRA)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS), Université de Liège, Universite Federale de Toulouse (PRES), Region Occitanie/Pyrenees-Mediterranee, France, Université de Toulouse (UT)-Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS), and Institut National Polytechnique de Toulouse - Toulouse INP (FRANCE)
Subjects: [SDV.BIO]Life Sciences [q-bio]/Biotechnology, Materials science, Ultrafiltration, membrane polymérique, solvant, 02 engineering and technology, 010402 general chemistry, 01 natural sciences, chemistry.chemical_compound, polymère, [CHIM.GENI]Chemical Sciences/Chemical engineering, Sustainable development, Génie chimique, Environmental Chemistry, [SPI.GPROC]Engineering Sciences [physics]/Chemical and Process Engineering, Génie des procédés, Process engineering, Flammability, Cellulose diacetate, Phase separation process, business.industry, Methyl lactate, 021001 nanoscience & nanotechnology, Pollution, 6. Clean water, 0104 chemical sciences, Solvent, Membrane, chemistry, 13. Climate action, 0210 nano-technology, business, Ecodesign
Abstract: International audience; The purpose of the research is to make a first step towards rationalizing green polymeric membrane preparation. A holistic methodological approach based on metrics that consider technical, environmental, health and safety issues have been suggested to assess sustainability of membrane preparation. Metrics have been applied to solvent substitution in a non-solvent induced phase separation process. The flammability hazard of three shortlisted alternative solvents has substituted the reprotoxicity hazard of common solvents. The ultrafiltration cellulose diacetate membranes prepared with methyl lactate as solvent have a greater renewable intensity and require a lower number of solvents for their preparation. Trade-offs between use of resources (polymer, solvent, energy…) and membrane properties are inevitable. Further socio-economic, risk and life cycle analysis are crucial to fully integrate ecodesign in membrane preparation.
Published: 2019
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40. A characteristic inlet boundary condition for compressible, turbulent, multispecies turbomachinery flows

Author: Laurent Gicquel, Marlène Sanjosé, Nicolas Odier, Florent Duchaine, Thierry Poinsot, Stéphane Moreau, Neuropsychiatrie : recherche épidémiologique et clinique (PSNREC), Université Montpellier 1 (UM1)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Université de Montpellier (UM), Université de Sherbrooke (UdeS), Institut de mécanique des fluides de Toulouse (IMFT), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées, (OATAO), Open Archive Toulouse Archive Ouverte, Centre National de la Recherche Scientifique - CNRS (FRANCE), Institut National Polytechnique de Toulouse - INPT (FRANCE), Université Toulouse III - Paul Sabatier - UT3 (FRANCE), Centre Européen de Recherche et Formation Avancées en Calcul Scientifique - CERFACS (FRANCE), Université de Sherbrooke (CANADA), Institut de Mécanique des Fluides de Toulouse - IMFT (Toulouse, France), Institut National Polytechnique de Toulouse - Toulouse INP (FRANCE), and Université Montpellier 1 (UM1)-Université de Montpellier (UM)-Institut National de la Santé et de la Recherche Médicale (INSERM)
Subjects: General Computer Science, Mécanique des fluides, Acoustic reflectivity, 01 natural sciences, Compressible flow, 010305 fluids & plasmas, Turbomachinery inflow conditions, Physics::Fluid Dynamics, Turbulence injection, Inviscid flow, 0103 physical sciences, Turbomachinery, [PHYS.MECA.MEFL] Physics [physics]/Mechanics [physics]/Fluid mechanics [physics.class-ph], [PHYS.MECA.MEFL]Physics [physics]/Mechanics [physics]/Fluid mechanics [physics.class-ph], Boundary value problem, 0101 mathematics, Total pressure, Physics, geography, geography.geographical_feature_category, Turbulence, General Engineering, Mechanics, Characteristic inlet boundary condition, Inlet, 010101 applied mathematics, Reynolds-averaged Navier–Stokes equations
Abstract: International audience; A methodology to implement non-reflecting boundary conditions for turbomachinery applications, based on characteristic analysis is described in this paper. For these simulations, inlet conditions usually corre- spond to imposed total pressure, total temperature, flow angles and species composition. While directly imposing these quantities on the inlet boundary condition works correctly for steady RANS simulations, this approach is not adapted for compressible unsteady Large Eddy Simulations because it is fully re- flecting in terms of acoustics. Deriving non-reflecting conditions in this situation requires to construct characteristic relations for the incoming wave amplitudes. These relations must impose total pressure, total temperature, flow angle and species composition, and simultaneously identify acoustic waves reach- ing the inlet to let them propagate without reflection. This treatment must also be compatible with the injection of turbulence at the inlet. The proposed approach shows how characteristic equations can be derived to satisfy all these criteria. It is tested on several cases, ranging from a simple inviscid 2D duct to a rotor/stator stage with turbulence injection.
Published: 2019
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41. Beech wood gasification in a dense and fast internally circulating fluidized bed

Author: Sid Ahmed Kessas, Mathieu Morin, Sébastien Pécate, Mehrdji Hemati, Centre National de la Recherche Scientifique - CNRS (FRANCE), Institut National Polytechnique de Toulouse - Toulouse INP (FRANCE), Université Toulouse III - Paul Sabatier - UT3 (FRANCE), and Institut National Polytechnique de Toulouse - INPT (FRANCE)
Subjects: Materials science, Biomass gasification, 020209 energy, General Chemical Engineering, Pellets, Energy Engineering and Power Technology, Biomass, 02 engineering and technology, complex mixtures, 020401 chemical engineering, 0202 electrical engineering, electronic engineering, information engineering, Génie chimique, FICFB, Fluidized bed combustion, Fluidization, 0204 chemical engineering, Génie des procédés, Gasifier, Wood gas generator, Olivine, Organic Chemistry, food and beverages, Syngas, Fuel Technology, Chemical engineering, Fluidized bed, visual_art, visual_art.visual_art_medium, Sawdust
Abstract: This study deals to improve the understanding of biomass thermo-chemical conversion in a dense and fast internally circulating fluidized bed. The experimental rig used in this study ran either as a dense fluidized bed or as a fast internally circulating fluidized bed. The effect of operating parameters, such as bed temperature (ranging from 750 to 850 °C), steam gas velocity (between 3 and 9.5 times the minimum fluidization velocity of bed material), steam to biomass mass ratio (ranging from 0.7 to 5.6 kg.kg −1) and biomass shape (sawdust and pellets) is investigated in both dense and fast internally circulating fluidized bed with olivine as bed material. In addition, the effect of bed material nature (olivine and sand) is also studied. Results indicated that syngas composition is strongly dependent on steam to biomass mass ratio. Moreover, it was found that syngas yield is favored by rising bed temperature and steam to biomass mass ratio while it is disadvantaged when fluidizing gas velocity increases. In addition, a greater syngas yield was obtained with olivine particles, compared to sand particles. The effect of bed material circulation flow rate was also investigated in fast internally circulating fluidized bed. Results showed that an increase in this parameter leads to a lower syngas yield. Finally, the experimental results presented in this paper were compared to ones reported in the literature and a good agreement was found.
Published: 2019
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42. Effect of trivalent chromium process on fatigue lifetime of 2024-T3 aluminium alloy

Author: Benoit Fori, Christine Blanc, Myriam Akanou, Romain Saillard, Grégory Odemer, Centre interuniversitaire de recherche et d'ingenierie des matériaux (CIRIMAT), Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC), Mecaprotec Industries, Centre National de la Recherche Scientifique - CNRS (FRANCE), Institut National Polytechnique de Toulouse - INPT (FRANCE), MÉCAPROTEC Industries (FRANCE), Université Toulouse III - Paul Sabatier - UT3 (FRANCE), and Institut National Polytechnique de Toulouse - Toulouse INP (FRANCE)
Subjects: Materials science, Aluminium alloy, Matériaux, 020209 energy, Intermetallic, chemistry.chemical_element, Fatigue lifetime, 02 engineering and technology, engineering.material, [SPI.MAT]Engineering Sciences [physics]/Materials, Chromium, Coating, 0202 electrical engineering, electronic engineering, information engineering, General Materials Science, Dissolution, Mechanical Engineering, Metallurgy, technology, industry, and agriculture, 021001 nanoscience & nanotechnology, Condensed Matter Physics, chemistry, Mechanics of Materials, visual_art, Conversion coating, Scientific method, visual_art.visual_art_medium, engineering, Crack initiation, 0210 nano-technology, Layer (electronics)
Abstract: International audience; The effect of a new alternative trivalent chromium conversion process on fatigue lifetime of a 2024-T3 aluminium alloy was investigated. The decrease in fatigue-life induced by coating process was related to the dissolution of coarse intermetallic particles during the deoxidation pre-treatment preceding the conversion layer growth.
Published: 2019
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43. Quasi-Variational Inequality Problems over Product Sets with Quasi-monotone Operators

Author: K. Cao Van, David Salas Videla, Didier Aussel, Procédés, Matériaux et Energie Solaire (PROMES), Université de Perpignan Via Domitia (UPVD)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Génie Chimique (LGC), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique - CNRS (FRANCE), Institut National Polytechnique de Toulouse - Toulouse INP (FRANCE), Université Toulouse III - Paul Sabatier - UT3 (FRANCE), Université de Perpignan Via Domitia - UPVD (FRANCE), and Institut National Polytechnique de Toulouse - INPT (FRANCE)
Subjects: Pure mathematics, Current (mathematics), 0211 other engineering and technologies, Quasi-monotone operator, Monotonic function, 010103 numerical & computational mathematics, 02 engineering and technology, Fixed point, Mathematical proof, 01 natural sciences, Theoretical Computer Science, [CHIM.GENI]Chemical Sciences/Chemical engineering, Operator (computer programming), Quasi-variational inequality, Product sets, Génie chimique, [SPI.GPROC]Engineering Sciences [physics]/Chemical and Process Engineering, [MATH]Mathematics [math], 0101 mathematics, Génie des procédés, Mathematics, Net-lower sign-continuity, 021103 operations research, Fixed points, Monotone polygon, Product (mathematics), Variational inequality, Stability, Software
Abstract: International audience; Quasi-variational inequalities are variational inequalities in which the constraint map depends on the current point. Due to this characteristic, specific proofs have been built to prove adapted existence results. Semicontinuity and generalized monotonicity are assumed and many efforts have been made in the last decades to use the weakest concepts. In the case of quasi-variational inequalities defined on a product of spaces, the existence statements in the literature require pseudomonotonicity of the operator, a hypothesis that is too strong for many applications, in particular in economics. On the other hand, the current minimal hypotheses for existence results for general quasi-variational inequalities are quasi-monotonicity and local upper sign-continuity. But since the product of quasi-monotone (respectively, locally upper sign-continuous) operators is not in general quasi-monotone (respectively, locally upper sign-continuous), it is thus quite difficult to use these general-type existence result in the quasi-variational inequalities defined on a product of spaces. In this work we prove, in an infinite-dimensional setting, several existence results for product-type quasi-variational inequalities by only assuming the quasi-monotonicity and local upper sign-continuity of the component operators. Our technique of proof is strongly based on an innovative stability result and on the new concept of net-lower sign-continuity.
Published: 2019
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44. Antimicrobial activities of novel bipyridine compounds produced by a new strain of Saccharothrix isolated from Saharan soil

Author: Abdelhadi Lahoum, Noureddine Bouras, Florence Mathieu, Christian Bijani, Selma P. Snini, Nasserdine Sabaou, Frédéric Pont, Gulli, Marie-Hélène, Laboratoire de Biologie des Systèmes Microbiens - LBSM (Alger, Algeria), École normale supérieure - Kouba-Alger (ENS Kouba-Alger), Laboratoire de chimie de coordination (LCC), Institut de Chimie de Toulouse (ICT-FR 2599), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS), Département de Biologie, Faculté des Sciences de la Nature et de la Vie et Sciences de la Terre, Université de Ghardaïa, Centre de Recherches en Cancérologie de Toulouse (CRCT), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Génie Chimique (LGC), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées, Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie de Toulouse (ICT-FR 2599), Université Fédérale Toulouse Midi-Pyrénées-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-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-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique - CNRS (FRANCE), Ecole normale supérieure de Kouba (ALGERIA), Institut National Polytechnique de Toulouse - Toulouse INP (FRANCE), Institut National de la Santé et de la Recherche Médicale - INSERM (FRANCE), Université Toulouse III - Paul Sabatier - UT3 (FRANCE), Université de Ghardaïa (ALGERIA), Centre de Recherches en Cancérologie de Toulouse - CRCT (Toulouse, France), and Institut National Polytechnique de Toulouse - INPT (FRANCE)
Subjects: 0301 basic medicine, Saccharothrix xinjiangensis, medicine.drug_class, Stereochemistry, Microorganism, Antibiotics, Pharmaceutical Science, 01 natural sciences, 03 medical and health sciences, Bipyridine, chemistry.chemical_compound, medicine, Génie chimique, [CHIM.COOR]Chemical Sciences/Coordination chemistry, Génie des procédés, Pharmacology, Caerulomycins, biology, Strain (chemistry), 010405 organic chemistry, lcsh:RM1-950, Carbon-13 NMR, [CHIM.COOR] Chemical Sciences/Coordination chemistry, biology.organism_classification, Antimicrobial, Antimicrobial compounds, Antagonistic activity, 0104 chemical sciences, 030104 developmental biology, lcsh:Therapeutics. Pharmacology, chemistry, Cyanogrisides, Proton NMR, Bacteria
Abstract: The actinobacterium strain ABH26 closely related to Saccharothrix xinjiangensis, isolated from an Algerian Saharan soil sample, exhibited highly antagonist activity against Gram-positive bacteria, yeasts and filamentous fungi. Its ability to produce antimicrobial compounds was investigated using several solid culture media. The highest antimicrobial activity was obtained on Bennett medium. The antibiotics secreted by strain ABH26 on Bennett medium were extracted by methanol and purified by reverse-phase HPLC using a C18 column. The chemical structures of the compounds were determined after spectroscopic (1H NMR, 13C NMR, 1H-1H COSY and 1H-13C HMBC spectra), and spectrometric (mass spectrum) analyses. Two new cyanogriside antibiotics named cyanogriside I (1) and cyanogriside J (2), were characterized along with three known caerulomycins, caerulomycin A (3), caerulomycin F (4) and caerulomycinonitrile (5). This is the first report of cyanogrisides and caerulomycins production by a member of the Saccharothrix genus. The minimum inhibitory concentrations (MIC) of these antibiotics were determined against pathogenic microorganisms. Keywords: Antagonistic activity, Antimicrobial compounds, Caerulomycins, Cyanogrisides, Saccharothrix xinjiangensis
Published: 2019
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45. A PENALIZATION METHOD TO TREAT THE INTERFACE BETWEEN A FREE-FLUID REGION AND A FIBROUS POROUS MEDIUM

Author: Nicola Luminari, Christophe Airiau, Alessandro Bottaro, Giuseppe Zampogna, Institut de mécanique des fluides de Toulouse (IMFT), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées, Dipartimento di Ingegneria Civile, Chimica e Ambientale [Genova] (DICCA), Universita degli studi di Genova, Centre National de la Recherche Scientifique - CNRS (FRANCE), Institut National Polytechnique de Toulouse - Toulouse INP (FRANCE), Université Toulouse III - Paul Sabatier - UT3 (FRANCE), Università degli Studi di Genova - UNIGE (ITALY), and Institut National Polytechnique de Toulouse - INPT (FRANCE)
Subjects: Materials science, Inertial frame of reference, Mécanique des fluides, Porous media, Biomedical Engineering, 02 engineering and technology, Physics::Fluid Dynamics, symbols.namesake, 0203 mechanical engineering, General Materials Science, [PHYS.MECA.MEFL]Physics [physics]/Mechanics [physics]/Fluid mechanics [physics.class-ph], Porosity, Cavity flow, Mechanical Engineering, Reynolds number, Laminar flow, Mechanics, Condensed Matter Physics, Apparent permeability, Porous interface, Permeability (earth sciences), 020303 mechanical engineering & transports, Mechanics of Materials, Modeling and Simulation, Compressibility, symbols, Porous medium, Free fluid
Abstract: International audience; The coupling between the flow through a fibrous porous medium and that in a free-fluid region is studied. The flow dynamics inside the porous medium are described using the volume averaging method applied to the incompressible Navier−Stokes equations in the laminar regime. The two different flow domains are coupled via a penalization method that consists of varying the porous medium properties (porosity and permeability) continuously across the interface. This approach permits the use of the same set of the equations throughout the whole domain. The averaging method is validated against simulations which fully account for the presence of cylindrical fibers positioned at the bottom wall of a square driven cavity. Numerical experiments are carried out for two different Reynolds numbers, large enough to ensure that inertial effects inside the porous domain are not negligible. Good agreement is found when comparing the two approaches.
Published: 2019
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46. Rationalizing the need of architecture-driven testing of interactive systems

Author: Canny, Alexandre, Bouzekri, Elodie, Martinie, Célia, Palanque, Philippe, Lárusdóttir, Marta Kristín, Winckler, Marco, Kuusinen, Kati, Bogdan, Cristian, Centre National de la Recherche Scientifique - CNRS (FRANCE), Institut National Polytechnique de Toulouse - Toulouse INP (FRANCE), Université Toulouse III - Paul Sabatier - UT3 (FRANCE), Université Toulouse - Jean Jaurès - UT2J (FRANCE), Université Toulouse 1 Capitole - UT1 (FRANCE), Eindhoven University of Technology - TU/e (NETHERLANDS), Interactive Critical Systems (IRIT-ICS), Institut de recherche en informatique de Toulouse (IRIT), Université Toulouse 1 Capitole (UT1), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse - Jean Jaurès (UT2J)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse 1 Capitole (UT1), Université Fédérale Toulouse Midi-Pyrénées, Eindhoven University of Technology [Eindhoven] (TU/e), Cristian Bogdan, Kati Kuusinen, Marta Kristín Lárusdóttir, Philippe Palanque, Marco Winckler, TC 13, WG 13.2, Systemic Change, and Institut National Polytechnique de Toulouse - INPT (FRANCE)
Subjects: [INFO.INFO-AR]Computer Science [cs]/Hardware Architecture [cs.AR], Computer science, System testing, 02 engineering and technology, [INFO.INFO-SE]Computer Science [cs]/Software Engineering [cs.SE], User input, Interface homme-machine, Field (computer science), Task (project management), [INFO.INFO-CR]Computer Science [cs]/Cryptography and Security [cs.CR], Software, Architectures Matérielles, Architecture-driven testing, 0202 electrical engineering, electronic engineering, information engineering, Génie logiciel, 0501 psychology and cognitive sciences, [INFO]Computer Science [cs], [INFO.INFO-HC]Computer Science [cs]/Human-Computer Interaction [cs.HC], Architecture, 050107 human factors, Interactive systems engineering, business.industry, Interactive system testing, 05 social sciences, 020207 software engineering, Modélisation et simulation, [INFO.INFO-MO]Computer Science [cs]/Modeling and Simulation, Systèmes embarqués, Test (assessment), Cryptographie et sécurité, [INFO.INFO-ES]Computer Science [cs]/Embedded Systems, Software engineering, business
Abstract: Part 3: Task Modelling and Task-Based Approaches; International audience; Testing interactive systems is known to be a complex task that cannot be exhaustive. Indeed, the infinite number of combination of user input and the complexity of information presentation exceed the practical limits of exhaustive and analytical approach to testing [31]. Most interactive software testing techniques are produced by applying and tuning techniques from the field of software testing to try to address the specificities of interactive applications. When some elements cannot be taken into account by the software testing technique, they are usually ignored. In this paper we propose to follow an opposite approach, starting from a generic architecture for interactive systems (including both software and hardware elements) for identifying in a systematic way, testing problems and testing needs. This architecture-driven approach makes it possible to identify how software testing knowledge and techniques can support interactive systems testing but also where the interactive systems engineering community should invest in order to test their idiosyncrasies too.
Published: 2019
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47. Efficiency of plasma elaborated sub-stoichiometric titanium oxide (Ti4O7) ceramic electrode for advanced electrochemical degradation of paracetamol in different electrolyte media

Author: Soliu O. Ganiyu, Marc Cretin, Stéphane Raffy, Christel Causserand, Mehmet A. Oturan, Nihal Oturan, Centre National de la Recherche Scientifique - CNRS (FRANCE), Ecole Nationale Supérieure de Chimie de Montpellier - ENSCM (FRANCE), Institut National Polytechnique de Toulouse - Toulouse INP (FRANCE), Saint-Gobain (FRANCE), Université Toulouse III - Paul Sabatier - UT3 (FRANCE), Université de Montpellier 2 (FRANCE), Université Paris-Est Marne-La-Vallée - UPEM (FRANCE), Université de Montpellier (FRANCE), Institut Européen des Membranes - IEM (Montpellier, France), Laboratoire Géomatériaux et Environnement (LGE), Université Paris-Est Marne-la-Vallée (UPEM), SAINT-GOBAIN CREe, Institut Européen des membranes (IEM), Centre National de la Recherche Scientifique (CNRS)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Université Montpellier 2 - Sciences et Techniques (UM2)-Institut de Chimie du CNRS (INC)-Université de Montpellier (UM), Laboratoire de Génie Chimique (LGC), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées, Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Institut de Chimie du CNRS (INC)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), and Institut National Polytechnique de Toulouse - INPT (FRANCE)
Subjects: Hydroxyl radicals, Anodic oxidation, Supporting electrolyte, chemistry.chemical_element, Filtration and Separation, 02 engineering and technology, Electrolyte, Electrochemistry, 7. Clean energy, Analytical Chemistry, [CHIM.GENI]Chemical Sciences/Chemical engineering, 020401 chemical engineering, [CHIM.ANAL]Chemical Sciences/Analytical chemistry, Chlorine, Génie chimique, [SPI.GPROC]Engineering Sciences [physics]/Chemical and Process Engineering, 0204 chemical engineering, Génie des procédés, TOC removal efficiency, [CHIM.CATA]Chemical Sciences/Catalysis, [CHIM.MATE]Chemical Sciences/Material chemistry, 021001 nanoscience & nanotechnology, 6. Clean water, Anode, Titanium oxide, chemistry, Chemical engineering, Ti4O7-ceramic anode, Electrode, Electro-Fenton, Degradation (geology), 0210 nano-technology
Abstract: International audience; This paper investigates the behavior of conductive Ti4O7 ceramic anode in different electrolytes during the degradation of the anti-inflammatory drug paracetamol (PCM) by advanced electrochemical oxidation processes mainly anodic oxidation with generation of H2O2 (AO-H2O2) and electro-Fenton (EF). Regardless of the medium, better degradation and mineralization efficiency was always observed with EF compared to AO-H2O2. The degradation of PCM was carried out by hydroxyl radical (OH) produced on the anode surface from water oxidation and mediated oxidation in the solution from oxidant species generated at the anode such as sulfate radicals and active chlorine species depending on the supporting electrolytes used, as well as OH generated homogeneously in the solution by electrochemically assisted Fenton’s reaction. Faster degradation was observed in Cl− compared to other media, but the solution was poorly mineralized. Highest total organic (TOC) removal efficiency with excellent degradation rate was attained in SO42− with either process, thus remain the best medium for advanced electrochemical wastewater treatment. Comparative studies with dimensional stable anode (DSA) and boron-doped diamond anode (BDD) showed similar trend of degradation and TOC removal efficiency with DSA anode achieving low mineralization power compared to Ti4O7 anode, whereas BDD showed slightly better efficiency than Ti4O7 in all electrolytes studied. The analysis of concentration of generated active chlorine species, especially ClO−, during AO-H2O2 decreased in the order: DSA > Ti4O7 > BDD. Therefore, the Ti4O7 electrode was found to be a promising anode material for an efficient treatment of PCM in SO42−, NO3− and ClO4− media but less effective in Cl− medium.
Published: 2019
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48. Tribolumen: a tribometer for a correlation between AE signals and observation of tribological process in Real-Time—Application to a dry steel/glass reciprocating sliding contact

Author: Malik Yahiaoui, Jean-Yves Paris, Khouloud Jlaiel, Jean Denape, Laboratoire Génie de Production (LGP), Ecole Nationale d'Ingénieurs de Tarbes, Institut National Polytechnique de Toulouse - INPT (FRANCE), and Institut National Polytechnique de Toulouse - Toulouse INP (FRANCE)
Subjects: Observation in real-time, Hertzian cracks, Materials science, Oscillation, Mechanical Engineering, Acoustics, Process (computing), Rigidity (psychology), Tribology, Surfaces, Coatings and Films, Acoustic emission, Reciprocating motion, Sliding contact, Wear debris, [SPI.MECA.MEMA]Engineering Sciences [physics]/Mechanics [physics.med-ph]/Mechanics of materials [physics.class-ph], lcsh:Q, Mécanique des matériaux, lcsh:Science, Reciprocating contact, ComputingMethodologies_COMPUTERGRAPHICS, Tribometer
Abstract: This paper deals with the development of an original apparatus called TRIBOLUMEN designed specifically for friction experiments on transparent materials. The friction measurement is synchronized with an acoustic emission (AE) sensor and the device is also equipped with a high-speed camera offering a direct view at the interface to gain a deeper understanding of tribological mechanisms. The TRIBOLUMEN device is in ball-on-flat contact configuration with a range of strokes from 5 to 500 &micro, m and an oscillation frequency from 5 to 600 Hz. The experiments showed that this device has an adequate rigidity and can detect subtle friction modifications of the oscillating contacts. The observation of a steel-on-glass contact in real-time highlighted the initiation of Hertzian cracks followed by the formation of debris in the contact. Using the synchronous measurement, these mechanisms were clearly associated with different stages in the friction measurement and in the AE signals, which permitted to identify the AE signature of Hertzian cracks.
Published: 2020
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49. A multimaterial based on metallic copper and spinel oxide made by powder bed laser fusion: A new nanostructured material for inert anode dedicated to aluminum electrolysis

Author: Valérie Baco-Carles, Pierre Chamelot, Isabelle Pasquet, Philippe Tailhades, Laurent Massot, Mathieu Gibilaro, Centre National de la Recherche Scientifique - CNRS (FRANCE), Institut National Polytechnique de Toulouse - INPT (FRANCE), Université Toulouse III - Paul Sabatier - UT3 (FRANCE), Laboratoire de Génie Chimique (LGC), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées, Centre interuniversitaire de recherche et d'ingenierie des matériaux (CIRIMAT), Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC), and Institut National Polytechnique de Toulouse - Toulouse INP (FRANCE)
Subjects: 0209 industrial biotechnology, Materials science, Additive manufacturing, Cermet, Oxide, 02 engineering and technology, engineering.material, 7. Clean energy, Industrial and Manufacturing Engineering, law.invention, Spinel ferrite, chemistry.chemical_compound, [CHIM.GENI]Chemical Sciences/Chemical engineering, 020901 industrial engineering & automation, 0203 mechanical engineering, law, Powder bed fusion, Génie chimique, [SPI.GPROC]Engineering Sciences [physics]/Chemical and Process Engineering, Selective laser melting, Porosity, Génie des procédés, Inert, Electrolysis, Metallurgy, Spinel, Inert anode, Metals and Alloys, Cryolite, Computer Science Applications, 020303 mechanical engineering & transports, chemistry, Modeling and Simulation, Ceramics and Composites, engineering, Nanostructuration
Abstract: International audience; Coherent 3D parts of cermets, made of spinel ferrite and metallic copper, are prepared in a nitrogen atmosphere by powder bed additive manufacturing of a mixture of oxide and metallic powders. The cermets obtained are constituted by the association of blocks of about 500 μm, which create between them, a relatively large porosity (# 35%). Each block is subdivided into intimately nested zones that are either predominantly metallic or predominantly oxide type. In the metal parts, a dispersion of oxide crystals is observed, whose size varies from ten nanometers to a few micrometers. A similar distribution of metal particles in the oxide zones is also demonstrated. The chemical compositions of metallic and oxide phases are slightly different from those in the initial powders. Due to the high energy density of the laser, the melting temperature of the metal and oxides could be reached and therefore this could explain the chemical composition variations in the phases and the shape of oxide and metallic nanometric grains. The process used can therefore be described as powder bed fusion. These nanostructured cermets have been used as "inert" anodes for the electrolysis of aluminum in molten cryolite. Although penalized by a high porosity, 5 mm in diameter anodes allowed to carry out an electrolysis for 4 h. Since Spark Plasma Sintering can greatly reduce their porosity, while retaining their specific microstructure, the implementation of additive manufacturing for producing "inert" anodes is therefore of real interest.
Published: 2020
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50. Balance control is impaired by mental fatigue due to the fulfilment of a continuous cognitive task or by the watching of a documentary

Author: Baptiste Trajin, Betty Hachard, Thierry Paillard, Hadrien Ceyte, Frédéric Noé, Institut National Polytechnique de Toulouse - Toulouse INP (FRANCE), Université de Pau et des Pays de l'Adour - UPPA (FRANCE), Université de Lorraine (FRANCE), Mouvement, Équilibre, Performance, Santé (MEPS), Université de Pau et des Pays de l'Adour (UPPA), Développement, Adaptation et Handicap. Régulations cardio-respiratoires et de la motricité (DevAH), Université de Lorraine (UL), Laboratoire Génie de Production (LGP), Ecole Nationale d'Ingénieurs de Tarbes, and Institut National Polytechnique de Toulouse - INPT (FRANCE)
Subjects: Adult, Male, medicine.medical_specialty, Mental fatigue, Posture, Control (management), Postural regulation, 050105 experimental psychology, Task (project management), Young Adult, 03 medical and health sciences, 0302 clinical medicine, Physical medicine and rehabilitation, [INFO.INFO-LG]Computer Science [cs]/Machine Learning [cs.LG], Cognitive resource theory, medicine, Humans, Attention, 0501 psychology and cognitive sciences, Force platform, Postural Balance, Balance (ability), Attentional resources, Sitting Position, Impaired Balance, General Neuroscience, 05 social sciences, Cognition, Apprentissage, Standing Position, Visual Perception, Female, Balance control, Subjective workload, Psychology, Psychomotor Performance, 030217 neurology & neurosurgery
Abstract: International audience; The aim of the present study was to evaluate the effects of mental fatigue (MF) induced by a 90-min continuous demanding cognitive task on balance control. Twenty healthy young participants were recruited. They had to perform three postural tasks (on a stable support with eyes open, with eyes closed and on a wobble board) while standing on a force platform before and after watching a documentary in a control condition or carrying out a prolonged continuous demanding cognitive task (AX-continuous performance test—AX-CPT) in a MF condition. Results showed that performing the AX-CPT generated. MF since participants felt a higher subjective workload from the NASA Task Load Index after the AX-CPT than after viewing the documentary. Both the AX-CPT and the viewing of the documentary impaired balance control, mainly by affecting postural regulatory mechanisms which evolved towards a less automatic and less complex regulation mode with an increased participation of cognitive resources. MF generated by the AX-CPT affected balance control by compromising the attentional processing, while the deleterious influence of watching a documentary on postural control could stem from an adverse effect of prolonged sitting on balance control during subsequent standing.
Published: 2020
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