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L'origine des relations de la France avec la Chine: Le premier voyage de l'Amphitrite en Chine par Paul Pelliot (1878-1945)
No full textL'origine des relations de la France avec la Chine,Le premier voyage de l'Amphitrite en Chine par Paul Pelliot (1878-1945), Paris, 1928Journal des Savants, Paris, 1928, décembr
Multi-technique radiometric assessment of a desert-marine ecosystem facilitating radiological-environmental safety in hyper-arid regions
No full textInternational audienceThis paper presents a rigorous, multi-technique assessment of radiometric and physiochemical characteristics of a desert-marine ecosystem in the United Arab Emirates (UAE). Current models and empirical data on the release, dispersion, retention and migration of radionuclides in hyper-arid regions are inadequate. This is a critical gap in the radiological-environmental assessments in the Arabian Peninsula, where industries producing radioactivity, such as oil and gas, mining, and both thermal and nuclear power generations, are expanding rapidly. This study offers the most diverse baseline data to date, laying the groundwork for an evidence-based radionuclide transport modeling in hyper-arid environments. It identifies the key isotopes to track and carefully selects a representative region for a comprehensive sampling. The Al Dhafra region of Abu Dhabi was chosen due to its importance in hosting oil, gas, and nuclear industries, and because it covers 71 % of the total area of the emirate. Around 30 different samples were collected, including rock, sand, groundwater, seawater, plants, and farm products. A tailored combination of advanced radiometric methods with XRD, ICP-MS, IC, and gamma spectrometry was developed for this complex and rare sample set. Majority of the instrumentation for this project were hosted in the Subatech Laboratories (France). The study yielded radioactivity compositions in the main arid environmental matrices, consistent with the previous research, and introduced novel findings on the probable host rocks to study for nuclear waste storage, desert shrubs as bioindicators, and camel milk as a medium for transfers to humans. •Diverse and multi-method radiometric characterization of an expansive hyper-arid desert region.•Baseline radionuclide concentrations measured for rocks, sand, waters, plants, and farm produces.•Identified primary rock types, groundwater chemistry and salinity, and plants for transport mechanisms.•Vital empirical data for nuclear and radioactivity-producing industries in hyper-arid ecosystems
Mise en œuvre des méthodologies scientifiques et Techniques dans une exposition muséale: Le projet ANR LAB in Virtuo
No full textInternational audienceLes objectifs du projet Lab In Virtuo sont de permettre une meilleure élicitation des Connaissances liées à la sauvegarde de dispositifs techniques et la création de nouveaux types de scénarios de médiation. Le projet s’appuie sur les technologies de la Réalité Virtuelle et Augmentée.En effet, nous estimons que l’implication du corps favorise les fonctions cognitives, que ce soit dans la création ou l’acquisition de nouvelles connaissances. Lors de la phase de création des connaissances, la Réalité Virtuelle et Augmentée permet d’immerger le corps d’experts ou d’anciens utilisateurs dans une scène reconstituant l’objet d’étude. Nous considérons que cette situation permettra une meilleure élicitation des connaissances. Pour utiliser un tel système en tant qu’interface de création de connaissances, nous devons alors nous appuyer sur un langage suffisamment formel pour être traité automatiquement et pour stocker les informations créées. Lors de la phase de restitution des connaissances, durant un scénario de médiation, nous considérons également que l’utilisation de ces technologies amélioré l’acquisition de ces connaissances par l’utilisateur. Cela est dû non seulement à une meilleure implication des utilisateurs grâce aux nouvelles technologies, mais surtout à l’immersion de l’utilisateur dans un environnement reconstitué et à ses capacités ‘interaction avec le système, ce qui n’est pas possible dans la réalité. Le projet est financé par l’ANR, est toujours en cours et se terminera fin 2025. Nous allons présenter ici l’architecture et le flot de conception proposés ainsi que la mise en place d’une exposition permettant d’éxpérimenter nos méthodologies
Petrographic and geochemical characterization of Eocene limestones from Thugga / Dougga (Tunisia) : implications for the provenance of stones used in construction and sculpture in the ancient town
No full textInternational audienc
An Adaptive Multiphase Finite Element Framework for Simulating Two-Dimensional Rotational Molding
No full textRotational molding, also known as rotomolding, is a widely used manufacturing process for composite tank liners. Developing this process to obtain high-quality liners is usually a long and delicate step. The implementation of numerical simulation can facilitate and expedite its development. It is challenging to obtain information about polymer movement through experimental methods. In this paper, we present a two-dimensional thermo-fluid simulation of rotomolding using the immersed boundary approach with the level-set technique. Numerical simulation using the Eulerian approach with the finite element method with anisotropic mesh refinement and the immersed boundary method has proven to be a powerful tool for analyzing and optimizing the molding processes with the help of implicit boundary and adaptive anisotropic meshing techniques. The finite element method is a valuable tool that allows us to combine several physical elements. This approach enables us to identify critical process variables and optimize design choices. To verify our methodology, we first simulated a 2D crosssection of the mold by incorporating a two-phase flow problem involving the polymer/air interface.</div
The Octroi de mer : Colonial origins and the long-term transformation of a French Overseas tax
No full textInternational audienc
How Particle Size Affects Consolidation Behavior, Strain and Properties of Li 6 PS 5 Cl Fast Ionic Conductors
No full textInternational audienceSolid‐state battery fabrication requires the densification of solid electrolytes to achieve optimal cycling performance and high energy density. However, the underlying compaction mechanisms of these electrolytes remain poorly understood. Here, we investigate the effect of pressure consolidation on the ionic conductor Li 6 PS 5 Cl with particle size distributions (PSD) ranging from 4 to 40 µm. Heckel analysis reveals that samples with smaller PSDs exhibit higher compressibility at lower pressures. X‐ray diffraction peak profiling shows that applied pressure induces lattice strain, leading to peak broadening, while pair distribution function analysis demonstrates a reduction in coherence length upon pressing. Dark‐field X‐ray microscopy further provides spatially resolved orientation maps, uncovering intragranular structural variations within individual Li 6 PS 5 Cl agglomerates after compression. To better understand the origin of stress fluctuations, we performed discrete element method simulations using the experimental PSDs. The results indicate that smaller particles and broader PSDs experience higher stresses, whereas monodisperse systems do not exhibit significant stress fluctuations with position or particle size. This suggests that the high strain observed cannot be attributed solely to smaller particles, but rather to size inhomogeneity. Overall, these findings highlight that both particle size and its distribution play a critical role in processing solid electrolytes for solid‐state batteries
Microreactor technology for CO2 methanation: A review on process intensification and system integration
No full textInternational audienceThe power-to-gas (PtG) process converts surplus renewable electricity into hydrogen via electrolysis, followed by CO2 methanation to produce synthetic methane. This integrated approach enhances the flexibility of hydrogen energy storage and transportation while achieves CO₂ valorization, supporting and advancing the UN's sustainable development goals. Traditional CO2 methanation in large fixed-bed equipment suffer from limited heat and mass transfer effiiciency, leading to the catalyst deactivation and compromised methanation performance. To overcome these challenges, microchannel-based reactors have been proposed as an alternate solution, offering enhanced heat and mass transfer performance, compact system volume, higher volumetric productivity and improved energy effiiciency. This paper presents a comprehensive literature review on research advances of the microchannel reactor technology for CO2 methanation. The review covers various aspects, including basic reaction mechanism, catalysts confiiguration, effects of operating factors, and strategies to intensify the CO2 methanation performance. In addition, special attention was given to integrated process coupling within methanation reaction, improving both reaction regulation and thermal energy management in methanation systems. The work provides a useful reference for developing high-effiiciency microchannel reactor systems for CO2 methanation, offering fundamental insights for future industrial-scale implementation
Who are the healthcare professionals involved in interprofessional team meetings in French multidisciplinary primary care centres? A quantitative analysis of eight centres
No full textInternational audienceBACKGROUND: Interprofessional collaboration is crucial for providing high-quality care to patients with complex conditions in primary care. In France, multidisciplinary primary care centres (MPCC) receive funding if they organise at least 6 interprofessional team meetings (ITM) per year to discuss complex patient situations and collectively define care strategies. It remains unclear how ITM have been implemented in France. This study analyses healthcare professionals’ involvement in ITMs within MPCCs. METHOD: A multicenter retrospective quantitative study in 8 French MPCCs based on the analysis of ITM reports for the period from 2018 to 2019 was conducted. RESULTS: 1733 patients’situations (n = 1733 cases) discussed during ITMs were analysed. The 8 MPCCs were heterogeneous in terms of geographical location, creation date, and size (3 MPCCs with > 20,000 patients followed by more than 60 professionals and 3 MPCCs with < 20 professionals). On average, five healthcare professionals attended each ITM, with huge variations among MPCCs. The nurse-general practitioner (GP) pair was central. At least one GP was present at 89% (n = 1469) and nurses at 38.15% (n = 630) of ITMs. Participation of other professionals was less frequent and varied according to the MPCC. Physiotherapists were present at 7.8% of ITMs, and other healthcare professionals were present at < 6% of ITMs, including pharmacists (3% of ITMs). In some cases, healthcare professionals external to MPCC, particularly those related to mental health, were also involved in ITMs. CONCLUSIONS: Depending on the MPCC, the professionals involved in ITM vary widely, with the nurse-GP pair at the centre. The relative absence of certain professionals needs to be analysed in order to encourage interprofessional working. TRIAL REGISTRATION: Not applicable