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L’exécution des peines applicables aux auteurs de violences intrafamiliales
No full textInternational audienc
Les arts du roman grec
No full textNuméro spécial de la revue Ancient Narrative, composés d'articles consacrés aux liens entretenus entre le roman grec antique et des formes d'expressions artistiques variées (peinture, musique, danse). Les études portent aussi bien sur l'analyse des textes antiques en eux-mêmes que sur leur réception à Byzance, et aux époques classique et contemporaine
La langue en marche : les recueils bilingues de Joséphine Bacon
No full textInternational audienceCe chapitre explore le bilinguisme dans la poésie de l'auteure innu Joséphien Bacon. Il étudie la façon dont la langue française et l'innu-aimun interagissent dans ces recueils
Introduction. La souveraineté résiduelle de l’État membre de l’Union européenne
No full textInternational audienc
New initialization procedures from phase stability testing in three-phase flash calculations for CO<sub>2</sub>-hydrocarbon mixtures
No full textInternational audiencePhase equilibrium calculations play an important role in a wide variety of applications in chemical and petroleum engineering. In this work, we focus on CO2-hydrocarbon mixtures, with applications ranging from enhanced oil recovery processes to CO2 storage. In compositional reservoir simulation, both robustness and efficiency are of utmost importance. The conventional approach for multiphase equilibrium consists of a sequence of phase stability and flash calculations. At each level of the stepwise process, stability testing is performed starting from several initial guesses; therefore, reducing the number of stability calls and using judiciously the information from stability to initialize a phase split are key points in developing an efficient stability-flash algorithm. Two new initialization strategies for multiphase flash calculations are proposed. The first one (improved stepwise initialization) follows the conventional procedure, but uses additional initial guesses. In the second one (improved multiple initialization), a three-phase split is initiated if at least three minima of the tangent plane distance (TPD) function are detected by stability analysis of feed composition. Both proposed methods are using all information from phase stability testing at each stage. Unlike in previous formulations, compositions at all minima of the TPD function, including trivial and positive TPDs are used to generate initial equilibrium constants. Highly robust routines are used, based on successive substitution iterations (SSI) in early iteration stages, followed by Newton iterations with modified Cholesky factorization and line search, in both stability and flash calculations. The proposed methods are tested and compared with the conventional procedure for several benchmark mixtures from the literature, containing hydrocarbon components and CO2. Phase diagrams are constructed in the P-Z plane, focusing on the number of stationary points of the TPD functions found in each step of the multiphase stability-flash algorithm and on how they must be efficiently used in initialization. For all the test mixtures, in the proposed stability-flash strategy, the number of calls of the stability and flash routines and the number of iterations in flash calculations are significantly reduced as compared to previous approaches, recommending the new approach as a useful tool in compositional simulation
Finite dimension thermodynamics-based preliminary design of multi-energy pumped thermal energy storage systems
No full textInternational audienc
Weak Anion-Exchange Chromatography Coupled with FT-ICR MS Resolves Polarity-Driven Molecular Signatures in Natural and Anthropogenic Dissolved Organic Matter
No full textInternational audienceWater-soluble emerging contaminants from fossil fuel–based materials pose increasing environmental risks, yet their detailed molecular characterization remains limited. These compounds often resemble natural dissolved organic matter (DOM), especially after photo-oxidation, which increases oxygen content and structural complexity. We developed a high-performance liquid chromatography (HPLC) method coupled to 21 T Fourier-transform ion cyclotron resonance mass spectrometry (FT-ICR MS) to enhance molecular analysis of both natural and anthropogenic DOM. The method incorporates a polymeric stationary phase functionalized with amine groups to promote interactions with carboxylic and phenolic moieties. A methanol-to-water gradient containing 2% diethylamine (DEA) promotes separation based on differences in hydrophilicity and functional group interactions with the stationary phase. Compared with direct infusion (DI), the HPLC-FT-ICR MS workflow mitigates ion suppression, enhances ionization efficiency, and broadens molecular coverage. For example, analysis of coal tar–derived water solubles yielded over 16,000 assigned formulas, twice as many as in DI-MS, including oxygen-containing polycyclic aromatic hydrocarbons (oxy-PAHs) and high H/C species poorly ionized under DI conditions. This method achieves efficient separation of chemically diverse compound classes, enabling ultrahigh-resolution MS analysis of complex environmental mixtures and advancing molecular-level understanding of both natural DOM and fossil fuel–derived contaminants
Industrial codes for CFD
No full textMasterNumerical simulation in fluid mechanics (or CFD) has become one of the basic tools used by engineers. In this course, we will study the methods often used in industrial codes and we will give the most active research strategies which will be the future standards. This course does not aim at teaching the practical use of a CFD code, rather at providing the key knowledge to understand what the codes contain and how to use them in a wise manner.Prerequisites: For this course, it is necessary to have attended a course of introduction to turbulenceThe main tackled points are: 1. Introduction to CFD (Computational Fluid Dynamics) ◦ Different phases and important points of a simulation: geometric modelling, meshing, physical modelling, computation, post-processing, ◦ Evaluation of computational costs linked with turbulence, computer power available today and conclusions for modelling, ◦ Different existing methods (RANS, hybrid, LES, DNS) : objectives, formalism, modelling, maturity, fields of application, ◦ Global picture of CFD codes: commercial codes (Fluent, StarCD, CFX, Powerflow…), « in-house » industrial codes, open-source codes (Open-Foam, Code_Saturne). 2. Standard method used in industrial projects: RANS modelling (Reynolds-averaged Navier-Stokes modelling): ◦ Closure problem, different levels of modelling, history, ◦ Similarity with continuum mechanics (constitutive relations), physical principles, ◦ Eddy-viscosity modelling: hypotheses, selection of the constitutive relation, k-epsilon models, k-omega models, Spalart-Almaras model, etc.: limits, corrections, variations, ◦ Reynolds-stress modelling: hypotheses, advantages, limits, algebraic modelling, ◦ Wall regions: physics, joint selection of the mesh and the model, law of the wall, low-Reynolds number models, 3. More expensive methods: ◦ Large-eddy simulation (LES): filtering, subgrid-scale stresses, modelling, fields of application, ◦ Hybrid RANS/LES methods: • zonal methods: principle, interface modelling, • continuous methods: formalism, URANS, OES, VLES, SNS, DES, SBES, SAS, PANS, PITM, HTLE
Transient performance of a commercial photovoltaic panel integrated with a bio-based phase change material: a numerical study
No full textInternational audienc
Impact of physical and sensory enrichment on the physiological status and disease resistance of triploid rainbow trout (Oncorhynchus mykiss)
No full textInternational audienceEnvironmental enrichment is increasingly recognised as a practical approach to improve the welfare of farmed fish. In rainbow trout (Oncorhynchus mykiss), a species of high economic and scientific relevance, few studies have simultaneously evaluated multiple dimensions of welfare under different enrichment strategies. Here, we investigated the effects of structural and sensory enrichments on growth, physiology, behaviour, neurochemistry, and disease resistance. Female triploid rainbow trout were reared for eight weeks under eight conditions: neutral control, positive stress control (no enrichment with additional handling stress), structural enrichments (rubber hose, rubber wall, floating grass mat, flexible laminaria), and sensory enrichments (continuous gas bubbles, blue light filter). Growth performance, blood markers of stress (cortisol, glucose, lactate), behavioural indicators, enrichment use, and brain monoamine turnover (5-HIAA/5-HT for serotonin; HVA/L-DOPA for dopamine) were assessed at three time points in eight weeks. To evaluate robustness, fish were subsequently challenged with Aeromonas salmonicida subsp. salmonicida. No significant differences in growth were detected across conditions, showed the highest weight gains, raising the hypothesis that they could provide benefits over longer rearing cycles, a question that will require dedicated long-term trials. Behavioural analyses indicated high use of structural enrichments and reduced stress-related behaviours under the blue filter and rubber hose conditions. Stress physiology revealed condition-specific reductions in lactate or cortisol, but no consistent enrichment effect across markers. Neurochemical analyses demonstrated condition-dependent modulation of serotonergic and dopaminergic turnover, with laminaria increasing both systems, blue filter reducing dopaminergic activity, and bubbles strongly decreasing serotonergic turnover. Infection outcomes showed slower disease progression in rubber hose, laminaria, blue filter, and rubber wall conditions, with rubber hose fish exhibiting the slowest mortality kinetics. Overall, our integrative approach highlights that environmental enrichment modulates multiple welfare dimensions in rainbow trout, with laminaria, blue filter, grass mat, and rubber hose emerging as the most promising strategies. These findings support enrichment as a valuable tool to promote fish welfare and resilience, while underlining the need for long-term and context-specific validation before implementation in aquaculture