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Fluorination renders the wood surface hydrophobic without any loss of physical and mechanical properties / Martial Pouzet in Industrial Crops and Products, vol 133 (July 2019)  

Public [article]  inIndustrial Crops and Products > vol 133 (July 2019) . - pp 133 - 141 Titre : Fluorination renders the wood surface hydrophobic without any loss of physical and mechanical properties Type de document : Article/Communication Auteurs : Martial Pouzet, Auteur ; M.A. Dubois, Auteur ; Karine Charlet, Auteur ; Alexis Béakou, Auteur ; Jean-Michel Leban , Auteur ; Mohamed Baba, Auteur Année de publication : 2019 Projets : 1-Pas de projet / Article en page(s) : pp 133 - 141 Note générale : bibliographie Langues : Anglais (eng) Résumé : (auteur) The main limiting factor for the use of solid wood lies in its highly hydrophilic character which is associated with the loss of its properties after moisture uptake. Therefore for limiting the negative impact of moisture in wooden structures, numerous research have been carried out in order to (i) protect the surface of wood by the addition of varied varnish or protections or to (ii) modify the wooden surfaces structure by the mean of different technologies such as thermal treatments. The former present the disadvantage to protect the wood surfaces for a limited period of time while the later present the disadvantage to reduce the mechanical properties. The aim was investigate how to reduce the hydrophilic character of wood without reducing physical and/mechanical properties. We use dynamic fluorination using F2 gas applied to wood samples (Douglas and silver fir) for reducing the hydrophilic character. The covalent grafting of fluorine atoms on a wood surface was highlighted by Fourier-Transform infrared spectroscopy and 19F solid state Nuclear Magnetic Resonance. The wood samples acquire a hydrophobic character comparable to that of Polytetrafluoroethylene, thanks to fluorination. The high durability of this treatment was also determined by aging tests under ambient atmosphere and UV irradiation. Moreover, this treatment gives a surface with a hydrophobic character without major structural (morphology, density and colour) and mechanical modifications. Maintaining those properties after fluorination, a dried gas/solid treatment without the use of toxic solvents and high temperatures seems to show a remarkable advantage over other physical chemical wood treatments. Numéro de notice : A2019-629 Affiliation des auteurs : LIF+Ext (2012-2019) Thématique : FORET Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.indcrop.2019.02.044 Date de publication en ligne : 13/03/2019 En ligne : https://doi.org/10.1016/j.indcrop.2019.02.044 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=95420 [article]

Space surveillance of epidemics: case of the Rift Valley fever / P. Sabatier (2001)

Public contenu dans Observing our environment from space / G. Begni (2002) Titre : Space surveillance of epidemics: case of the Rift Valley fever Type de document : Article/Communication Auteurs : P. Sabatier, Auteur ; M.A. Dubois, Auteur ; R. Lancelot, Auteur ; P. Hendrickx, Auteur ; J.P. Lacaux, Auteur Editeur : Lisse et Amsterdam : Balkema (August Aimé) Année de publication : 2001 Conférence : EARSeL 2001, 21st international symposium, Observing our environment from space : news solutions for a new millennium 14/05/2001 16/05/2001 Paris France Importance : pp 317 - 323 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de télédétection [Termes IGN] épidémie [Termes IGN] maladie virale [Termes IGN] prédiction [Termes IGN] surveillance sanitaire Résumé : (Auteur) The unexpected appearance of new infectious diseases, often of zoonotic origin, is a surprising phenomenon at the end of the beginning of the third millennium (TAYLOR, L.H. & WOOLHOUSE M.E.J. 2000). To trigger off epidemics, and not only to entail sporadic forms, these new agents require amplification effects linked to natural or artificial changes in the environment. This project, CNES sponsored, develops a predictive model using remote sensing data for monitoring a vectorborn disease. The study is based on a thorough modelling of the epidemic process of a zoonotic haemorrhagic fever (Rift Valley Fever, RV17); in a Sahelian area (basin of the Senegal River). The preliminary results of the space modelling: (i) express the periodicity of the outbreaks; and (H) display the change of the space behaviour of RVF epidemics when the infection, or transmission probability, rises above a threshold for bond percolation on the network. An increase in the number of moving populations causes faster spreading by increasing the number of vertices in the graph's largest connected component. This integrative approach of the S2E consortium ("Space Surveillance of Epidemics") will open a new field for early warning epidemiological systems, able to alert on and to predict the geographical extension of diseases. Numéro de notice : C2001-021 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Communication DOI : sans Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=64929