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La délibération parlementaire en droit constitutionnel : éléments d'une institutionnalisation prudentielle de l'incertitude
No full textInternational audienc
« Paradox and impact of the evolution of IP legislation in China ». NUS –USPC Research project on International Negotiations and Trade linkages in the Asia Pacific region (University of Singapore, 23-24 August 2018) (followed by publication on Sustainability and the Future of Trade Governance, Asia Europe Journal, 2023)
No full textInternational audienc
La lectrice empêchée. Violences historiques, politiques de contrôle social et lecture rétives
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Le mandinka (màndìŋkàkáŋò): Quelques contrastes pertinents pour l'enseignement du français aux locuteurs du mandinka
No full textPrésentation linguistique succincte du mandinka (langue, phonologie, grammaire) dans une perspective contrastive mandinka/françai
Role and importance of microorganisms in plant nutrition and remediation of potentially toxic elements contaminated soils
No full textInternational audienc
Convective outgassing efficiency in planetary magma oceans: Insights from computational fluid dynamics
No full textInternational audiencePlanetary atmospheres are commonly thought to result from the efficient outgassing of cooling magma oceans. During this stage, vigorous convective motions in the molten interior are believed to rapidly transport the dissolved volatiles to shallow depths where they exsolve and burst at the surface. This assumption of efficient degassing and atmosphere formation has important implications for both the early and long-term planetary evolution, but has never been tested against fluid dynamics considerations. Yet, during a convective cycle, only a finite fraction of the magma ocean can reach the shallow depths where oversaturated volatiles exsolution can occur, and a large-scale circulation can exist for vigorously convecting fluids in the presence of inertial effects. This can prevent a substantial magma ocean volume from rapidly reaching the planetary surface. Therefore, we conducted computational fluid dynamics experiments of vigorous 2D and 3D Rayleigh-Bénard convection at Prandtl number of unity to characterize the ability of the convecting fluid to reach shallow depths at which volatiles are exsolved and extracted to the atmosphere. We find that the outgassing efficiency is essentially a function of the magnitude of the convective velocities. This allows deriving simple expressions to predict the time evolution of the amount of outgassed volatiles as a function of the magma ocean governing parameters. We show that for plausible cases, the time required to exsolve all oversaturated water can exceed the magma ocean lifetime in a given highly vigorous transient stage, leading to incomplete or even negligible outgassing. Furthermore, the planet size and the initial magma ocean water content, through the convective vigor and the exsolution depth, respectively, strongly affect magma oceans degassing efficiency, possibly leading to divergent planetary evolution paths and resulting surface conditions. Overall, despite vigorous convection, for a significant range of parameters, convective degassing appears not as efficient as previously thought
Practical Theory of Spectral Evolution in an Organic Laser Diode
No full textThe spectrum of the light emitted by a microcavity OLED is strongly time dependent on the nanosecond timescale after switch-on of the pump mechanism. This is one reason why convincing confirmation of laser operation in such device is difficult. The simple theory here presented is helpful in interpreting observed light-emission behavior. One important finding is that the occurrence in the optical spectrum of a narrow Lorentzian on top of a spontaneousemission pedestal is no guarantee for observed laser operation. Another finding is that reabsorption by the singlet excitons leads to the highest gain when the cavity is detuned to the red side of the emission spectrum. This is confirmed by experimental observations on an optically pumped organic laser diode
Laser-based dew detection
No full textInternational audienceAgriculture is in need for new sustainable solutions in order to reduce their phytosanitary products utilization. To this end, the early detection of the necessary conditions for disease development is a key to their reduction. Combined with a laser source, such a tool can do fast measurements on a field scale and, by doing so, help farmers in containing diseases. Thus, a laser-based sensor has been developed for wetting monitoring. Using the Heiligenschein phenomenon, it has been proved effective on both hydrophilic and hydrophobic surfaces in controlled condition
