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Diffusion and physicochemical behavior of chloride and sodium ions in C-S-H gel pores : A molecular dynamics investigation
No full textInternational audienceCalcium silicate hydrate (C-S-H) gel is an amorphous material with a complex, disordered structure that complicates the understanding of its atomic-scale properties. While many studies have investigated ionic diffusion in C-S-H pores, the behavior of sodium (Na + ) and chloride (Cl -) ions, particularly in relation to the Ca/Si ratio, is not well understood. In this study, atomistic models of C-S-H were developed with varying Ca/Si ratios, pore sizes, and NaCl concentrations. Molecular dynamics simulations were used to calculate the self-diffusion profiles of Na + and Cl -ions. Results indicate that pore size strongly affects diffusivity and adsorption through confinement and electrical double layer effects. The solid surface influences ionic mobility up to approximately 1.2 nm. The Ca/Si ratio has minimal impact on the diffusion profiles of nonadsorbed ions, but its rise enhances Cl -mobility near the surface and increases chloride binding capacity, consistent with prior studies
Projets alimentaires territoriaux et stratégies alimentaires locales : une comparaison France -Brésil
No full textInternational audienceThis text compares civil society and national and local policy actions targeting the food system in Brazil and France. It shows how the two countries have adopted mirror strategies, with France relying on a multitude of local initiatives led by local authorities and civil society, with little national support, while Brazil first developed a powerful national policy influenced by organised citizen networks to disseminate it at regional and local levels.Ce texte, en version longue par rapport à l'ouvrage à paraître, compare les actions de la société civile et politiques nationales et locales visant le système alimentaire, entre le Brésil et la France. Il montre comment les deux pays ont adopté des stratégies en miroir, la France se basant sur une multitude d'initiatives locales portées par les collectivités et la société civile, avec un faible portage national, pendant que le Brésil a d'abord développé une puissante politique nationale influencée par les réseaux citoyens organisés pour la diffuser aux échelles régionale et locale
Optimal energy management in multi energy microgrid with combined heat and power system and demand side response integration
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Wave Propagation and Polarization Effects in RF Based Sensing and Communication for Smart Insoles
No full textInternational audienceWireless smart insoles are increasingly used for motion analysis, providing critical insights for healthcare, sports performance, and injury prevention. A key challenge is accurately measuring and wirelessly transmitting foot movement and placement data in real time, independently of inertial measurement units tied to biomechanical models, which only estimate gait parameters for a limited range of activities such as walking or running. Radio-frequency phase-based ranging presents a promising solution for a broader range of gait analysis applications, including irregular movement of athletes in sport or people with diseases like Parkinson’s. However, wireless system design must address two key challenges: (1) antenna robustness against the non-deterministic properties of the ground and the proximity of the body, and (2) polarization mismatch due to foot movement. This study is the first to numerically and experimentally investigate how foot motion and insole operating conditions affect wave propagation and wireless communication at 2.45 GHz. We analyze the impact of soil properties and antenna polarization, demonstrating that vertical polarization significantly improves signal transmission compared to horizontal polarization, with a gain of 6–10 dB at a height of 5cm. This improvement, driven by surface wave propagation, provides insights into the antenna design strategies for wireless insoles that can enhance the accuracy of phase-based ranging for foot distance measurement, as confirmed through simulations and experimental validation. These findings contribute to the energy-efficient, real-time ranging and communication enabled by optimized antenna designs, reducing power consumption and improving motion analysis for a wide range of users, including athletes requiring precise performance metrics and patients undergoing diagnostics or rehabilitation
Using the ecological and digital transitions to restructure groups
No full textInternational audienceThe ecological and digital transitions have become a central theme in public employment policies which are providing funding to professional sectors and companies to help employees adapt their qualifications and skills. These new directions, driven at international and European levels, are being embraced by governments. France has chosen to place continuing vocational training at the heart of a market of ecological and digital transitions, in which employees are called upon to build their “training path”, while groups and companies use these transitions and the legal provisions that accompany them to restructure. This raises the question of the allocation of responsibilities in the construction of digital and ecological transitions
Development of a numerical model for measuring the electrical conductivity (EC) of a cake batter
No full textInternational audienceThe electrical conductivity (EC) of materials represents their ability to conduct electrical current and determines the power dissipated within the material. This parameter can be temperature and electric field dependent. When EC is measured in the electric fields used for ohmic heating, the increase in temperature results in heating nonuniformity in the measuring cell. As a result, the relationship between EC and temperature cannot be accurately determined. In addition, for cake batter, starch gelatinization occurs during the measurement, leading to more complex EC curves. To address these issues, this study proposes a numerical method for determining EC that accounts for temperature non-uniformity. This model is coupled with a starch gelatinization model. The principle is based on the estimation of the EC using the method of least squares between the experimental temperature and the numerical one. The estimation of the EC of the cake batter consists of two steps: first, the device was characterized with xanthan and potassium chloride solutions of known electrical conductivities. A conversion efficiency of 0.77 was found. This efficiency was used to estimate the EC of the cake batter as a function of temperature and for different electric fields. Results showed that EC became independent of the electric field from 34.57 V/cm
Territoria Naturalia. Aménager sans altérer, entre partage et réserve
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Fixation judiciaire de l'indemnité d'expropriation : variations autour du principe de l'interdiction pour le juge de statuer ultra petita
No full textInternational audienceCour de cassation, 3e civ., 9 octobre 2025, no 24-12.637, Communauté d'agglomération du Centre littoral c/ Société Goldust Immobiliaria, publié au Bulletin ; JCP N 2025. Actu. 1251 ; JCP 2025. Actu. 1185 ; D. actu. 24 oct. 2025, note O. Desumeur ; Gaz. Pal. 28 oct. 2025, no 35, obs. C. Berlaud ; Juris-Data no 2025-01678
De l’offre à la vente notariée : l’introuvable moment de la vente ?
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