19 research outputs found

    Characterization of diffusionnal transfers of bound water and water vapor in beech and spruce

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    In the hygroscopic range of wood and without any thermal gradient, transfer of water vapor and bound water is carried out by diffusion. In this study, we experimentally determined the diffusivity values for vapor and bound water in the three orthotropic directions of wood for two species (beech and spruce). We then evaluated in steady-state the fluxes for the two forms of water and showed the influence of wood morphologies and transfer direction on these fluxes

    Simulation of Flow of Mixtures Through Anisotropic Porous Media using a Lattice Boltzmann Model

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    We propose a description for transient penetration simulations of miscible and immiscible fluid mixtures into anisotropic porous media, using the lattice Boltzmann (LB) method. Our model incorporates hydrodynamic flow, diffusion, surface tension, and the possibility for global and local viscosity variations to consider various types of hardening fluids. The miscible mixture consists of two fluids, one governed by the hydrodynamic equations and one by diffusion equations. We validate our model on standard problems like Poiseuille flow, the collision of a drop with an impermeable, hydrophobic interface and the deformation of the fluid due to surface tension forces. To demonstrate the applicability to complex geometries, we simulate the invasion process of mixtures into wood spruce samples.Comment: Submitted to EPJ

    Regolith science with the cameras on the MMX Rover

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    The JAXA Martian Moons Exploration (MMX) mission [1] has a primary objective to study the formation and origins of Phobos and Deimos. The MMX spacecraft will also deploy a CNES/DLR rover to the surface of Phobos [2,3]. This rover will be the first of its kind to attempt wheeled-locomotion on a low gravity surface. As such, this rover provides a unique opportunity to study not only the surface properties of Phobos, but also regolith dynamics on small-bodies. This information is valuable for understanding the surface processes and geological history of Phobos in addition to being of high importance to the landing (and sampling) operations of the main MMX spacecraft [1]

    Characterization of diffusionnal transfers of bound water and water vapor in beech and spruce

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    In the hygroscopic range of wood and without any thermal gradient, transfer of water vapor and bound water is carried out by diffusion. In this study, we experimentally determined the diffusivity values for vapor and bound water in the three orthotropic directions of wood for two species (beech and spruce). We then evaluated in steady-state the fluxes for the two forms of water and showed the influence of wood morphologies and transfer direction on these fluxes

    CHARACTERIZATION OF DIFFUSIONNAL TRANSFERS OF BOUND WATER AND WATER VAPOR IN BEECH AND SPRUCE

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    In the hygroscopic range of wood and without any thermal gradient, transfer of water vapor and bound water is carried out by diffusion. In this study, we experimentally determined the diffusivity values for vapor and bound water in the three orthotropic directions of wood for two species beech (Fagus sylvatica) and spruce (Picea sp.). We then evaluated in steady-state the fluxes for the two forms of water and showed the influence of wood morphologies and transfer direction on these fluxe

    Recent sedimentary processes along the Makran trench (Makran active margin, off Pakistan)

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    Nicolas Mouchot, Lies Loncke, Geoffroy Mahieux, Julien Bourget, Siegfried Lallemant, Nadine Ellouz-Zimmermann and Pascale Leturmyhttp://www.elsevier.com/wps/find/journaldescription.cws_home/503350/description#descriptio

    Bronze Sculptures and Lead Objects Tell Stories About Their Creators: Investigation of Renaissance Sculptures and Ancient Ingots by Means of Neutron Tomography

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    Renaissance bronze objects from the Rijksmuseum (Amsterdam) col- lection and lead ingots from ancient roman shipwrecks found near Sicily (Italy) were studied by means of neutron tomography. This was done with the aim to visualize and to measure the inner structures of the objects. In this way information about the manufacturing processes in the 16th century and the conservation status from the inside of the bronze sculptures was gained. Inscriptions found under the corrosion layer of the lead ingots gave hints about the trade routes in the past. Neutron imaging was proven perfect to transmit the relatively thick layers of Pb and Cu alloys while ceramic remains, soldering connections and corrosion effects become visible

    Trends of methicillin-resistant Staphylococcus aureus (MRSA) and Enterobacteriaceae-producing extended-spectrum beta-lactamase (ESBLE) in eastern France: a three-year multi-centre incidence study.

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    International audienceThe objective of this study was to describe trends for the years 2004 to 2006 in the incidence of methicillin-resistant Staphylococcus aureus (MRSA) and Enterobacteriaceae-producing extended-spectrum beta-lactamase (ESBLE) in a large hospital network (70 hospitals in eastern France). The incidence of MRSA per 1,000 patient-days decreased significantly from 0.55 in 2004 to 0.45 in 2006. This trend was observed in medicine and surgery units, whereas MRSA incidence was stable in intensive care, paediatric and obstetric units. The incidence of blood cultures positive for MRSA remained stable at 0.04 per 1,000 patient-days. Conversely, the incidence of ESBLE increased significantly from 0.04 in 2004 to 0.08 in 2006. This increase was caused by the spread of ESBLE-producing Escherichia coli. The mean consumption of alcohol-based gel and solution (ABS), expressed in litres per 1,000 patient-days, was 3.3 in 2002, 4.5 in 2003, 5.4 in 2004 and 6.4 in 2005. There was no association between the consumption of ABS and MRSA incidence. These findings suggest that the French recommendations for the control of multi-drug-resistant bacteria (MDRB) have been effective in reducing, or at least stabilising, the incidence of MRSA in an international context of general increase. However, the diffusion of ESBLE-producing E. coli is a matter of concern and should be carefully monitored
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