Search results for "Diffusion"

Le sport en Franche-Comté : spécificité et organisation de l'espace régional

2007

This paper is a multi-scale analysis of sports in the Franche-Comté region. After reviewing available data sources, the specificities of regional sport are highlighted such as the Nordic activities which are facilitated by the physical environment. Taking into account rates of club membership, the region is an intermediate space between West and South France while professional sport suffers from the absence of large cities. Finally, some regional patterns of sport organizations are examined examplified by three sports which have varying levels of diffusion.

De la machine à la mécanique, l’article mechanique de l’Encyclopédie

2017

International audience; Les Lumières en mouvement Les Lumières en mouvement La circulation des idées au xviii e siècle sous la direction d'Isabelle Moreau ENS ÉDITIONS « circulation, s. f. (Gram.) se dit en général de tout mouvement périodique ou non, qui ne se fait point en ligne droite… » Encyclopédie, article circulation, octobre 1753. D'une discipline à l'autre, d'un texte à l'autre, les théories (et leurs images) se transforment, empruntant des chemins de traverse parfois surprenants. Les études rassemblées ici s'intéressent aux conditions matérielles de la circulation et de l'évolution des idées, ainsi qu'à la substance religieuse, philosophique, politique, sociale, culturelle de ces …

Un passage difficile : la diffusion de la recherche en formation.

2007

On the Schwarzschild Effect in 3D Two‐Photon Laser Lithography

2019

International audience; The two‐photon Schwarzschild effect in photoresists suitable for 3D laser lithography is revisited. The study ranges over seven orders of magnitude in exposure time (from 1 µs to 10 s) and investigates a wide variety of different photoresist compositions. For short exposure times (“regime I”), the laser power at the polymerization threshold can scale with the inverse square root of the exposure time, as naively to be expected for two‐photon absorption. Substantial deviations occur, however, for low photoinitiator concentrations. For intermediate exposure times (“regime II”), a Schwarzschild‐type of behavior is found, as discussed previously. For very long exposure ti…

Contribution to the study of interaction between residual stress and oxygen diffusion in a deformable and reactive solid

2011

The aim of this PhD work is to highlight the interactions between the mechanical stress and the chemical composition within diffusion of matter process for a reactive solid. The chronological evolution of our work goes from a parametric numerical study to an experimental study and reveals the role of mechanical stresses on the oxygen diffusion process.Different origins of mechanical stress were first numerically analysed from the point of view of their impacts on the process of oxygen diffusion into a metal (Zr) or a ceramic (UO2) subjected to an oxidizing environment. This approach allowed us: to identify a surface treatment (shot-peening) able to generate a residual specific stress field,…

Fiber-based light source for biomedical applications

2013

This manuscript presents the work done concerning the development of a light source used for biomedical imaging and more particularly for coherent Raman scattering imaging. In fact an efficient broadcasting of these ones is hampered by the need of two synchronized and wavelength shifted pulses. As so, the handiness and frequency conversion capabilities of nonlinear fiber optics are used to circumvent this technological lock. First of all, an easy wavelength tunable source is set by the use of the self-shifting in optical frequency of a soliton. A study of the main fiber parameters lead to shifts of 320 to more than 500 nm which allows interesting molecular resonances imaging (≈ 1000-4000 cm…

Hydrothermal Ageing Effect on Reinforcement Efficiency of Nanofibrillated Cellulose/Biobased Poly(butylene succinate) Composites

2022

Nanofibrillated cellulose (NFC) is a sustainable functional nanomaterial known for its high strength, stiffness, and biocompatibility. It has become a key building block for the next-generation of lightweight, advanced materials for applications such as consumer products, biomedical, energy storage, coatings, construction, and automotive. Tunable and predictable durability under environmental impact is required for high performance applications. Bio-based poly (butylene succinate) (PBS) composites containing up to 50% NFC content were designed and aged in distilled water or at high relative humidity (RH98%). PBS/NFC composites are characterized by up to 10-fold increased water absorption ca…

Image Mean Square Displacement analysis: a new method to study protein diffusion in cell membranes

2017

The image mean square displacement...

Development of a coupled diffusion denuder system combined with gas chromatography/mass spectrometry for the separation and quantification of molecul…

2009

This study concerns the development of a coupled diffusion denuder system capable of separating and quantifying gaseous molecular iodine (I(2)) and two other highly reactive iodine species, ICl and HOI, which are collectively named activated iodine compounds (AIC). Both I(2) and AIC are key species in the atmospheric chemistry of iodine. 1,3,5-Trimethoxybenzene (1,3,5-TMB)- and alpha-cyclodextrin/(129)I(-) (alpha-CD/(129)I(-))-coated denuders proved to be suitable for the collection of gaseous AIC and I(2), respectively. The experimental collection efficiencies for AIC (tested as ICl) and I(2) agreed well with the theoretical values for gas flow rates in the range between 300 and 1800 mL mi…

Extensive Evaluation of a Diffusion Denuder Technique for the Quantification of Atmospheric Stable and Radioactive Molecular Iodine

2010

In this paper we present the evaluation and optimization of a new approach for the quantification of gaseous molecular iodine (I(2)) for laboratory- and field-based studies and its novel application for the measurement of radioactive molecular iodine. alpha-Cyclodextrin (alpha-CD) in combination with (129)I(-) is shown to be an effective denuder coating for the sampling of gaseous I(2) by the formation of an inclusion complex. The entrapped (127)I(2) together with the (129)I(-) spike in the coating is then released and derivatized to 4-iodo-N,N-dimethylaniline (4-I-DMA) for gas chromatography-mass spectrometry (GC-MS) analysis. The (127)I(2) collected can be differentiated from the (129)I(-…