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Artificial neural network modeling and VFT correlation of experimental dynamic viscosity of the 2-(2-ethoxyethoxy)ethanol + 2-propanol binary mixtures at high pressures and temperatures
No full textInternational audienc
The CO2 + 2,3,4-trimethylpentane and CO2 + 2,2,4,6,6-pentamethylheptane binary systems: high–pressure phase equilibria measurements
No full textInternational audienceTwo binary systems containing CO2 and a branched alkane were newly studied in this work: CO2 + 2,3,4-trimethylpentane and CO2 + 2,2,4,6,6-pentamethylheptane. Their fluid phase behavior was investigated using a high pressure variable-volume cell and a synthetic method. Saturation pressures were visually measured from (293.15 et 363.15) K and for 10 different CO2 mole fractions for both mixtures. Whatever the considered system, no liquid-liquid immiscibility was observed in this temperature range, suggesting a continuous vapor-liquid critical curve between the pure components critical points. A total of 160 points were acquired: 149 bubble points and 11 dew points. These new experimental data were satisfactory modeled by using the Peng-Robinson equation of state with a temperature-dependent interaction parameter, kij (T), fitted against the data
Workload Shifting Techniques: From Digital Inebriation to Sobriety
No full textInternational audienceComputing demand in cloud environments has grown exponentially over the past decade, due to the increase in cloud workload related to new services such as artificial intelligence, autonomous vehicles, augmented reality, etc. As a result, the ICT sector has seen its carbon emissions increase. It is possible to adopt less energy-intensive strategies and consume electricity produced by renewable energy to limit the increase in carbon emissions. In this paper, we present a review of the workload-shifting techniques available for sustainable workload deployment, providing an innovative framework that can be used to analyze energy-aware approaches that apply any type of shifting technique. We identified three main concepts: compute a workload at a different time, deploy a workload and/or its data in a different location, or use alternative processing to provide a good-enough option for a workload. A definition and some examples are given for each shifting concept, and then we explore the opportunities and challenges of combining different shifting techniques
Compte-rendu de « Emmanuelle Reungoat et François Buton (dir.), Idées reçues sur les Gilets jaunes. Un marqueur des luttes sociales contemporaines (Le Cavalier bleu, 2024) »
No full textNational audience« Publié plus de cinq ans après le surgissement des Gilets jaunes en novembre 2018, cet ouvrage collectif dirigé par Emmanuelle Reungoat et François Buton s’inscrit dans la démarche durkheimienne qui exige de rompre avec les prénotions en passant les idées reçues sur ce mouvement au crible d’enquêtes approfondies fondées sur des monographies de terrain, des entretiens biographiques, des questionnaires ou des échantillons représentatifs. Fruit de l’engouement des chercheurs en sciences sociales pour les Gilets jaunes, il réunit les contributions de vingt-sept politistes, sociologues, historiens, géographes et anthropologues. Il articule des travaux de doctorants consacrés aux Gilets jaunes et des analyses d’universitaires confirmés qui appréhendent le mouvement au prisme de leur objet d’étude antérieur. La thèse selon laquelle “les Gilets jaunes sont bien un mouvement social, et un mouvement pas comme les autres” (p. 19), qui marque l’histoire des luttes sociales, structure cet ouvrage composé de trois grandes parties.
module H2-biochem if MRST
No full texth2-biochem (https://www.sintef.no/projectweb/mrst/download/release-notes-for-mrst-2025b/)A new module for modeling microbial biogeochemical reactions in Underground Hydrogen Storage (UHS). The module provides a fully implicit, fully coupled framework that extends MRST's compositional simulator to account for hydrogen-consuming microbes (e.g., methanogenic archaea).Key features include: (1) Microbial growth/decay via a double Monod formulation (2) Søreide–Whitson Equation of State for accurate H₂ phase behavior (3) Modeling of bio-clogging and salinity effects on H2 solubility.Contributed by Elyes Ahmed (Sintef Digital), Stéphanie Delage Santacreu (Université de Pau et des Pays de l’Adour, Pau France).Reference: Elyes Ahmed, Brahim Amaziane, Salaheddine Chabab, Stéphanie Delage Santacreu, Guillaume Galliéro, Olav Møyner, Xavier Raynaud, Modeling and simulation of coupled biochemical and two-phase compositional flow in underground hydrogen storage, International Journal of Hydrogen Energy, Volume 168, 2025, 150947, ISSN 0360-3199, https://doi.org/10.1016/j.ijhydene.2025.150947
Internal handling, shell accumulation and effects of cobalt on the gastropod <i>Ampullaceana balthica</i>
No full textInternational audienceCobalt (Co) is central to the development of new low-carbon energies, becoming an element of emerging concern for the environment. Gastropods are widely distributed in aquatic ecosystems and represent the largest group of the phylum Mollusca. However very few studies have focused on Co impacts on gastropods. We thus aimed to examine the internal handling of Co in gastropods and its excretion into the shell in order to better understand its toxic actions and how these organisms cope with Co stress. To that end, Ampullaceana balthica was exposed to increasing Co concentrations (6, 30 and 60 μg·L−1) using outdoor flow-through mesocosms for 28 days in June and October. They were analyzed for their growth, reproduction and Co accumulation in the soft bodies and the outer shell part every week. Cobalt distribution in soft tissues and its subcellular distribution were further examined.Cobalt induced a decrease in the egg mass number and a delay in their hatching. Its accumulation in the soft tissue and the outer shell exhibited distinct seasonal patterns. Linear relationships with the ambient Co concentrations were only evident in the soft tissues in June and in the shell in October. For both periods, Co was mainly distributed in the hepatopancreas and the mantle, particularly in their mitochondria and granules fractions. We thus discussed the possible pathways of Co from the soft tissues to the shell involving granules. The present results demonstrate that using shells as bioindicators of metal exposure has certain limitations, depending on the organism life cycle
Unrevealed prokaryotic diversity in a peridotite massif in an underground mine of New Caledonia
No full textInternational audienceThe microbial diversity in an abandoned mine accessing the Tiebaghi peridotite massif in New Caledonia was studied. The site allowed sampling of alkaline water (pH 8.9-9.9) flowing through fractures, with no contamination from the atmosphere, ensuring optimal gas recovery. Two sampling campaigns collected gas samples, revealing variable gas flux. At one site, no bubbling was observed. At the other site, methane (0.11-1.2 mol%), CO 2 (0.054-0.08 mol%), and O 2 (7.5-18.3 mol%) were present, while H 2 was below detection. Methane showed a biogenic δ 13 C signature of -90‰ vs. vPDB (Vienna Pee dee Belemnite). The physico-chemistry indicated an oligotrophic environment with recent oxic meteoric water. Microbial biofilms, formed by microorganisms in the formation waters, included methanogenic archaea mainly from Methanobacteriaceae, likely responsible for methane production. In this oligotrophic environment, oxic waters supported methanotrophs (Methylococcaceae) and methylotrophs (Methylophilaceae), which may structure community dynamics. The presence of nitrogencycle families such as Nitrosococcaceae and Rhodocyclaceae raises questions, given the apparent depletion of reduced nitrogen compounds. The absence of H 2 suggests it may be consumed by hydrogenotrophic prokaryotes (Methanobacteriaceae, Comamonadaceae), reducing detectable levels. This study is the first to detail microbial diversity in the Tiebaghi massif, offering new insights into peridotite-associated microbial communities
