WorldWideScience

Sample records for cardiovasculaire ressource electronique

  1. Havets ressourcer

    DEFF Research Database (Denmark)

    Carstensen, Jacob; Dahl, Karsten; Gislason, Henrik

    , øger skibstrafikken og lokker flere og flere turister til. Blandt meget andet. Mens vi gerne vil sikre gode udviklingsmuligheder for de maritime erhverv, skal vi tage hensyn til klima og miljø. Det blå hav er ikke en uudtømmelig ressource, og pladsen er trang i de danske farvande. Hvem, der fremover må...

  2. Les manifestations cardiovasculaires chez les hemodialyses ...

    African Journals Online (AJOL)

    Le but de l'étude est d'analyser sur une période de 12 mois chez 75 patients en hémodialyse chronique, âgés de 38ans en moyenne, le les aspects cliniques, thérapeutiques et évolutifs des manifestations cardiovasculaires. La prévalence est de 87,20% chez les patients. Les signes fonctionnels les plus fréquents sont la ...

  3. Evaluation of radiolabelled annexin A5 for scintigraphic imaging of cell processes (necrosis/apoptosis) in cardiovascular diseases; Evaluation de radiotraceurs derives de l'annexine A5 pour l'imagerie scintigraphique de processus cellulaires (apoptose/necrose/thrombose) en pathologie cardiovasculaire (Ressource electronique)

    Energy Technology Data Exchange (ETDEWEB)

    Sarda-Mantel, L

    2007-03-15

    Annexin A5, a 35KDa protein, specifically binds with high affinity to phosphatidylserine (P.S.) which is actively redistributed to the external leaflet of plasmic membranes in apoptotic cells and activated platelets. Annexin A5 radiolabelled with {sup 99m}Tc({sup 99m}Tc-ANX5) was developed by Strauss (stanford, Usa) to image apoptosis in vivo: tumours cells apoptosis induced by chemo-radiotherapy, ischemia/reperfusion lesions in animals and patients, graft rejection. Additionally, many in vitro data suggest that annexin A5 also stains necrosis (membrane disruption), which occurs in all types of cell death. This preclinical work aimed to evaluate the potential interest of {sup 99m}Tc-ANX5 imaging as a clinical tool in cardiovascular diseases. Four studies performed in rat models of myocardial infarction by coronary ligation and ischemia-reperfusion, and in rat models of subacute and acute (isoproterenol-induced) myocarditis show the ability of {sup 99m}Tc-ANX5 to detect in vivo cardio myocytes death by apoptosis and necrosis. Another study demonstrates that {sup 99m}Tc-ANX5 is highly accurate to evaluate in vivo the biological activity of parietal thrombus in a rat model of elastase-induced abdominal aortic aneurysm. These results suggest that {sup 99m}Tc-ANX5 imaging could be used in patients for non invasive diagnosis, prognostic evaluation in acute myocarditis and in various thrombotic cardiovascular diseases. (author)

  4. Cardiovasculaire en gastro-intestinale risico's bij selectieve en niet-selectieve NSAID's

    NARCIS (Netherlands)

    van den Bemt, B.J.F.; Benraad, H.B.; Rasker, Johannes J.

    2007-01-01

    - Er is veel discussie geweest over de cardiovasculaire en gastro-intestinale veiligheid van cyclo-oxygenase(COX)-2-selectieve en traditionele NSAID’s. De nationale en internationale richtlijnen zijn hierover niet eenduidig. - COX-2-selectieve NSAID’s lijken de kans op ernstige maag-darmcomplicaties

  5. Cholestérol alimentaire et morbi/mortalité cardiovasculaire

    Directory of Open Access Journals (Sweden)

    Hansel Boris

    2015-03-01

    Full Text Available Si l’hypercholestérolémie est un facteur de risque avéré des maladies cardiovasculaires, le rôle du cholestérol alimentaire dans la survenue de ces maladies reste discuté. À l’origine, les travaux d’Anitshkow chez le lapin ont montré qu’une alimentation riche en cholestérol se traduit par le développement de plaques d’athérome. Les études d’intervention chez l’homme ont examiné l’effet du cholestérol alimentaire et/ou des œufs sur les lipides plasmatiques, aboutissant à des résultats contradictoires. Elles ont également fait émerger la notion complexe d’hypo- et d’hyper-répondeur au cholestérol. L’épidémiologie observationnelle ne permet pas non plus de conclure à un effet délétère du cholestérol alimentaire chez l’homme. Néanmoins, chez les sujets diabétiques, une association positive entre la consommation et l’incidence des événements cardiovasculaires est retrouvée assez constamment, sans que l’on puisse l’expliquer de manière convaincante. Il n’existe pas d’essai clinique examinant l’impact des aliments riches en cholestérol sur la survenue des événements cardiovasculaires. Toutefois, les résultats des études MRFIT et PREDIMED ne vont pas dans le sens d’un effet délétère du cholestérol alimentaire. À l’inverse, les travaux réalisés sur le transporteur intestinal du cholestérol NPC1L1 sont en faveur de l’intérêt d’inhiber l’absorption du cholestérol pour réduire l’incidence des maladies cardiovasculaires. L’ensemble des données disponibles n’est pas en faveur d’un rôle clé du cholestérol alimentaire dans la survenue des maladies cardiovasculaires. Elles ne permettent donc pas d’en faire une cible prioritaire du régime à proposer pour prévenir les maladies cardiovasculaires.

  6. Epaisseur de l'intima-média carotidienne et facteurs de risque cardio-vasculaires

    Science.gov (United States)

    Herinirina, Nicolas Fanantenana; Rajaonarison, Lova Hasina Ny Ony Narindra; Herijoelison, Andry Roussel; Ahmad, Ahmad

    2015-01-01

    Introduction L’épaisseur intima-média de la carotide commune mesurée à l’échographie est un marqueur de risque cardio-vasculaire. L'objectif de ce travail est d’établir la corrélation entre l’épaisseur de l'intima-média carotidienne commune et les facteurs de risque cardio-vasculaire chez des sujets asymptomatiques. Méthodes Etude transversale descriptive et analytique portant sur 77 sujets de 40 ans et plus chez qui nous avons évalué les facteurs de risque cardio-vasculaire et analysé leur association avec l’épaisseur intima-média carotidienne commune. Résultats L’épaisseur intima-média augmentait avec l’âge. Les hommes avaient une épaisseur intima-média plus marquée que les femmes. L'hypertension artérielle, le diabète et la dyslipidémie sont corrélés à l’épaisseur de l'intima-média contrairement au tabagisme. Conclusion L’âge élevé et le sexe masculin sont les facteurs déterminants de la majoration de l’épaisseur intima-média carotidienne commune surtout si s'ajoutent l'hypertension artérielle, le diabète ou la dyslipidémie. PMID:26327990

  7. Directeur, Ressources Humaines | CRDI - Centre de recherches ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Jouer un rôle de leader et établir, dans la planification stratégique du CRDI (qui ... du fonctionnement (administration de la rémunération, recrutement, dotation, ... le vice-président, Ressources, établir le programme des politiques stratégiques ...

  8. Acides gras oméga 3 et maladies cardiovasculaires : approches épidémiologiques

    Directory of Open Access Journals (Sweden)

    Ducimetiere Pierre

    2004-01-01

    Full Text Available La prise alimentaire d’acides gras oméga 3 a de nombreuses conséquences biologiques en particulier dans les domaines intéressant le risque cardiovasculaire (thrombose, métabolisme lipidique, inflammation. A partir de l’énorme littérature épidémiologique sur le sujet, on peut conclure que la consommation de poisson « gras » ou d’oméga 3 à longue chaîne a un effet protecteur sur la mortalité coronaire et plus généralement sur les maladies cardiovasculaires. Il existe des indications en faveur d’un effet similaire de l’apport en alphalinolénique (ALA. Les essais de prévention secondaire avec des oméga 3 à longue chaîne ont confirmé ces résultats mais les essais de conseils nutritionnels favorisant la consommation d’ALA ne sont qu’indicatifs. Il n’existe guère « d’evidence » en faveur du rôle des oméga sur le développement quantitatif de l’athérome alors que leur effet protecteur sur la vulnérabilité cardiaque aux arythmies est bien établie. Ces données expérimentales et cliniques fournissent une base biologique à la relation observée entre un apport augmenté de poisson ou d’oméga 3 et un risque abaissé de mort subite dans plusieurs études de cohortes.

  9. Gouvernance et gestion des ressources communes au Vietnam ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Gouvernance et gestion des ressources communes au Vietnam. La subvention permettra au Collège d'agriculture et de foresterie de l'Université de Huê de se pencher sur des questions reliées à la gestion des ressources communes et à la pauvreté dans ... New funding opportunity for gender equality and climate change.

  10. Gradients socioéconomiques du risque cardiovasculaire chez les enfants et les adolescents canadiens

    Directory of Open Access Journals (Sweden)

    Y. Shi

    2016-01-01

    Full Text Available Introduction : Les maladies cardiovasculaires (MCV et leurs facteurs de risque présentent des gradients socioéconomiques clairs chez les adultes canadiens, mais présentent des ambiguïtés chez les enfants. L'objectif de cette étude est de vérifier l'existence ou non de gradients socioéconomiques dans les marqueurs physiologiques du risque de MCV chez les enfants et les adolescents canadiens. Méthodologie : À partir des données transversales combinées de l'Enquête canadienne sur les mesures de la santé 2007-2011, nous avons étudié, chez 2 149 enfants (6 à 11 ans et 2 073 adolescents (12 à 17 ans et selon le sexe, les marqueurs de risque cardiovasculaire suivants : excès de poids (y compris l'obésité, score de capacité aérobique (SCA, pression artérielle (PA, lipides sanguins (totaux, cholestérol LDL et HDL, triglycérides, métabolisme du glucose et protéine C réactive (CRP. Des analyses de régression logistique et de régression linéaire multidimensionnelles ont permis de dégager les tendances relatives au risque cardiovasculaire en fonction de la suffisance du revenu du ménage et du niveau de scolarité des parents, après ajustement en fonction de l'âge et de l'origine ethnique, et après stratification par groupe d'âge et par sexe. Résultats : La prévalence de l'obésité était sensiblement plus élevée chez les jeunes garçons que chez les jeunes filles (prévalence de 18,5 %, intervalle de confiance [IC] à 95 % : 15,6 à 21,5 contre 7,7 %, IC à 95 % : 5,2 à 10,3. Toutefois, des gradients socioéconomiques négatifs ont été observés en ce qui concerne le risque d'adiposité chez les jeunes filles et les adolescentes, et non chez les garçons. Parmi les enfants et les adolescents, les garçons étaient en meilleure condition physique que les filles (SCA moyen de 541, IC à 95 % : 534 à 546 contre 501, IC à 95 % : 498 à 505 chez les enfants; 522, IC à 95 % : 514 à 529 contre 460, IC à 95 % : 454

  11. Coordonnateur, (h/f) Ressources humaines | CRDI - Centre de ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Sous la direction de directrice des ressources humaines, le coordonnateur, ... est le principal responsable de la gestion des dossiers papier et électroniques de la ... ordre de priorité, tenir l'emploi du temps à jour, gérer un système de contrôle, ...

  12. Formulation de farine de fonio enrichie en ressources alimentaires ...

    African Journals Online (AJOL)

    Mots clés: fonio (Digitaria exilis), alimentation complémentaire, ressources alimentaires locales au Bénin, enfants de 6 – 23 mois, formulation de farine de céréale. English Title: Developing a fonio flour enriched with local food resources for complementary feeding of young children in Benin. English Abstract. The objective ...

  13. Gestionnaire, Solutions d'affaires en ressources humaines | CRDI ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Gestion des ressources humaines du CRDI (stratégie et planification) ... mise en oeuvre des stratégies et des politiques ainsi qu'à l'amélioration continue dans .... les domaines des RH suivants : acquisition de talents (dotation et recrutement), ...

  14. Electronic sorting of radioactive ores; Triage electronique des minerais radioactifs

    Energy Technology Data Exchange (ETDEWEB)

    Sandier, J.

    1958-01-15

    Electronic sorting of radioactive ores consists in passing the rock lumps, after sieving, one by one in front of radioactivity detectors; these detectors command electromechanical systems which class the ores according to their radioactivity level. This note sets on the state of progress of the work going on at the D.R.E.M.: use of scintillometers for γ-ray detection, with circuits carrying magnetic memories to improve their operation; results of laboratory and semi-industrial tests on several deposits; description of the material, data on the first factory project; notes on the financial returns of the process. A description is also given of the electronic sorting material used skip by skip for a first rough classification of the ores according to their content, as they leave the shaft. (author) [French] Le triage electronique des minerais radioactifs consiste a faire passer, apres criblage, les cailloux un par un devant des detecteurs de radioactivite; ces detecteurs commandent des systemes electromecaniques qui classent les minerais selon leur niveau de radioactivite. La note expose l'etat d'avancement des travaux en cours a la D.R.E.M: utilisation des scintillometres pour la detection des rayonnements γ, de circuits comportant des memoires magnetiques pour ameliorer le fonctionnement; resultats d'essais de laboratoire et semi-industriels sur plusieurs gisements; description du materiel, donnees sur le premier projet d'usine; notes sur la rentabilite du procede. Est egalement decrit le materiel de triage electronique skip par skip utilise pour une premiere classification grossiere des minerais selon leurs teneurs, des la sortie des puits. (auteur)

  15. Afrique : ressources minières, environnement et gouvernance ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    25 janv. 2011 ... ils regorgent de richesses inouïes », assure Bonnie Campbell, directrice du Groupe de recherche sur les activités minières en Afrique (GRAMA) et titulaire de la Chaire C.-A. Poissant de recherche sur la gouvernance et l'aide au développement, faisant référence aux ressources minières et pétrolières dont ...

  16. LA COGESTION DES RESSOURCES NATURELLES - Abrégé ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    6 oct. 2011 ... L'ENJEU Selon les estimations, de 600 à 900 millions de paysans pauvres habitent les régions marginales, écologiquement fragiles, des pays en développement. Leur survie dépend largement de l'accès aux ressources naturelles qui les entourent, mais la croissance démographique et l'extraction ...

  17. Gestion des ressources hydriques dans un contexte de ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Gestion des ressources hydriques dans un contexte de changements climatiques dans des établissements humains côtiers en Angola. Durant la guerre civile angolaise, de très nombreux habitants des zones de conflit en milieu rural se sont déplacés vers des endroits vulnérables aux phénomènes climatiques extrêmes, ...

  18. RESSOURCES ÉLECTRONIQUES ET BIBLIOTHÈQUES JURIDIQUES

    OpenAIRE

    Coulon, Françoise

    2013-01-01

    Ce mémoire examine l'intégration des ressources électroniques en bibliothèque juridique. Il se nourrit de plusieurs études, tant sur la progression de la documentation électronique dans diverses bibliothèques, que sur l'évolution de l'offre éditoriale et l'évolution des usages et des pratiques induits par l'électronique dans les bibliothèques. Afin de dégager des tendances et des enjeux propres aux bibliothèques juridiques, cette étude se complète par une enquête de terrain à travers l'observ...

  19. TIC pour un accès équitable aux ressources humaines en sante en ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Ce projet vise à mieux comprendre comment les TIC peuvent faciliter la distribution équitable des ressources humaines en santé en renforçant et consolidant des activités ... Technologies de l'Information et de la Communication (TIC) pour un Accès équitable aux Ressources Humaines en santé qualifiées, motivées et bien ...

  20. Ressources minières en Afrique : Quelle réglementation pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Ressources minières en Afrique : Quelle réglementation pour le développement ? Couverture du livre Ressources minières en Afrique : Quelle réglementation pour le développement ? Directeur(s):. Bonnie Campbell. Maison(s) d'édition: Presses de l'Université du Québec, CRDI. 6 juillet 2009. ISBN : 9782760525214.

  1. Wind Ressources in Complex Terrain investigated with Synchronized Lidar Measurements

    Science.gov (United States)

    Mann, J.; Menke, R.; Vasiljevic, N.

    2017-12-01

    The Perdigao experiment was performed by a number of European and American universities in Portugal 2017, and it is probably the largest field campaign focussing on wind energy ressources in complex terrain ever conducted. 186 sonic anemometers on 50 masts, 20 scanning wind lidars and a host of other instruments were deployed. The experiment is a part of an effort to make a new European wind atlas. In this presentation we investigate whether scanning the wind speed over ridges in this complex terrain with multiple Doppler lidars can lead to an efficient mapping of the wind resources at relevant positions. We do that by having pairs of Doppler lidars scanning 80 m above the ridges in Perdigao. We compare wind resources obtained from the lidars and from the mast-mounted sonic anemometers at 80 m on two 100 m masts, one on each of the two ridges. In addition, the scanning lidar measurements are also compared to profiling lidars on the ridges. We take into account the fact that the profiling lidars may be biased due to the curvature of the streamlines over the instrument, see Bingol et al, Meteorolog. Z. vol. 18, pp. 189-195 (2009). We also investigate the impact of interruptions of the lidar measurements on the estimated wind resource. We calculate the relative differences of wind along the ridge from the lidar measurements and compare those to the same obtained from various micro-scale models. A particular subject investigated is how stability affects the wind resources. We often observe internal gravity waves with the scanning lidars during the night and we quantify how these affect the relative wind speed on the ridges.

  2. Modèles de gestion des ressources forestières du massif ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Expérimentation Participative et Adaptative de Modèles de Gestion des Ressources Forestières dans la Chaine Montagneuse de l'Atlas (Algérie, Maroc, Tunisie) : rapport final (17 mars 2009 au 18 septembre 2012). Download PDF. Reports. Unité de transformation de cire d'abeille (Commune de M'Sara). Download PDF ...

  3. Élaboration de politiques nationales sur l'accès aux ressources ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    amélioration des cultures et de gestion des ressources naturelles sont compromises. Les lois et les mécanismes en vigueur, comme les droits de propriété intellectuelle (DPI), ne conviennent pas à la protection du savoir traditionnel, car ils protègent les ...

  4. Modules de formation en durabilité et mobilisation des ressources

    International Development Research Centre (IDRC) Digital Library (Canada)

    Wind

    apprendre à lier la mobilisation des ressources à la planification stratégique; ... chercheurs et des ONG collaborant à des initiatives de défense de politiques. La ...... établissements membres à recruter des stagiaires qui ont contribué à la.

  5. Agent de gestion des ressources (h/f) | CRDI - Centre de recherches ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Sous la direction du vice-président, Ressources, et chef de la direction ... moyens de susciter et de gérer l'évolution des processus, des outils et des politiques; ... la mise à jour des instruments de délégation des pouvoirs, et les préparer pour ...

  6. Conflit armé en Colombie : différentes ressources, différents conflits ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Nouveau webinaire IWRA/CRDI sur les changements climatiques et la gestion adaptive de l'eau. L'Association internationale de ressources en eau (IWRA), en étroite collaboration avec le CRDI, organise un webinaire intitulé "Changements climatiques et gestion adaptive de l'eau: des... Voir davantageNouveau webinaire ...

  7. Essai de Modélisation de la Gestion des ressources en eau dans la ...

    African Journals Online (AJOL)

    et de l'environnement, tenues a Dublin et a Rio de Janeiro en 1992. Depuis ces conférences ..... actuelle, de la charge de pollution, des ressources et des fournitures ..... Management (Case study: Saf-Saf River Basin, North. East of Algeria).

  8. Agent de ressourcement (h/f) | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Résumé des fonctions L'agent de ressourcement est le point de ... Tenir à jour les données consignées dans les modules du système de gestion des ... au chargé de projet des recommandations fondées sur des renseignements à jour et ...

  9. Geothermal Resources in China Les ressources géothermiques de la Chine

    Directory of Open Access Journals (Sweden)

    An K. S.

    2006-11-01

    Full Text Available The present paper deals mainly with the distribution features, briefly describes the geology in the three geothermal fields of different types in Beijing, Yangbajing of Xizang (Tibet, and Dengwu of Guangdong, and finally gives on account of the development and utilization of geothermal resources. Up to now, more, than 2,500 geothermal water points (including hot springs, hot-water wells, and hot water in mines have been found. Four major geothermal zones and three basic types of geothermal resources can be preliminarily divided. In China, geothermal resources have been used for the purposes of power generating, industry and agriculture, medical treatment, etc. This article contains a sketch map showing the distribution of geothermal water in China. Cet article porte sur les caractéristiques de répartition, les types essentiels et les conditions de formation des ressources géothermiques, explique brièvement la géologie de trois types différents de champs géothermiques : Pékin, Yanbajin de Xiang (Tibet et de Dengwu de Guangdong et enfin présente l'exploitation et l'utilisation des ressources géothermiques. Jusqu'à présent, on a découvert plus de 2500 points d'eaux géothermiques (y compris sources thermales, puits des eaux thermales et les eaux thermales apparues dans les mines. lis sont subdivisés en quatre zones géothermiques principales et trois types essentiels de ressources géothermiques. Les ressources géothermiques ont trouvé leur utilisation dans la production de l'électricité, dans l'industrie, l'agriculture et le traitement médical, etc. On trouve dans cet article une esquisse de répartition des ressources géothermiques de la Chine.

  10. Approche pour la recommandation de ressources pédagogiques basée sur les liens sociaux

    OpenAIRE

    Tadlaoui , Mohammed; George , Sébastien; Sehaba , Karim

    2015-01-01

    Conférence EIAH 2015; Les systèmes de recommandation ont pour objectif de proposer des ressources pertinentes à une personne en utilisant certaines informations sur les utilisateurs et les ressources du système. Notre travail s’intègre dans le contexte des systèmes de recommandation de ressources pédagogiques et plus particulièrement des systèmes qui utilisent des informations sociales. En se basant sur les résultats de recherche dans le domaine des systèmes de recommandation, des réseaux soc...

  11. A superheterodyne spectrometer for electronic paramagnetic. Resonance; Spectrometre superheterodyne de resonance paramagnetique electronique

    Energy Technology Data Exchange (ETDEWEB)

    Laffon, J L [Commissariat a l' Energie Atomique, Grenoble (France). Centre d' Etudes Nucleaires

    1963-12-15

    After a few generalities about electron paramagnetic resonance, a consideration of different experimental techniques authorises the choice of a particular type of apparatus. An EPR superheterodyne spectrometer built in the laboratory and having a novel circuit is described in detail. With this apparatus, many experimental results have been obtained and some of these are described as example. (author) [French] Apres quelques generalites sur le phenomene de resonance paramagnetique electronique, une synthese des differentes techniques experimentales, permet de fixer le choix d'un type d'appareillage. Un spectrometre de RPE superheterodyne realise en laboratoire et comportant un circuit original est expose dans le detail. Cet appareil a permis de nombreux resultats experimentaux dont quelques-uns sont decrits a titre d'exemple. (auteur)

  12. Electronic specific heat of transition metal carbides; Chaleur specifique electronique de carbures de metaux de transition

    Energy Technology Data Exchange (ETDEWEB)

    Conte, R [Commissariat a l' Energie Atomique, Fontenay-aux-Roses (France). Centre d' Etudes Nucleaires

    1964-07-15

    The experimental results that make it possible to define the band structure of transition metal carbides having an NaCI structure are still very few. We have measured the electronic specific heat of some of these carbides of varying electronic concentration (TiC, either stoichiometric or non-stoichiometric, TaC and mixed (Ti, Ta) - C). We give the main characteristics (metallography, resistivity, X-rays) of our samples and we describe the low temperature specific heat apparatus which has been built. In one of these we use helium as the exchange gas. The other is set up with a mechanical contact. The two use a germanium probe for thermometer. The measurement of the temperature using this probe is described, as well as the various measurement devices. The results are presented in the form of a rigid band model and show that the density of the states at the Fermi level has a minimum in the neighbourhood of the group IV carbides. (author) [French] Les donnees experimentales permettant de preciser la structure de bandes des carbures de metaux de transition de structure NaCI sont encore peu.nombreuses. Nous avons mesure la chaleur specifique electronique de certains de ces carbures, de differentes concentrations electroniques (TiC stoechiometrique ou non, TaC et mixtes (Ti, Ta) - C). Nous donnons les principales caracteristiques (metallographie, resistivite, rayon X), de nos echantillons, et nous decrivons l'appareillage de chaleur specifique a basse temperature realise. Dans l'un nous utilisons l'helium comme gaz d'echange. L'autre est monte avec un contact mecanique. Les deux utilisent une sonde au germanium comme thermometre. La mesure de la resistance de cette sonde est decrite, ainsi que les differents montages de mesure. Les resultats, presentes dans un modele de bande rigide, font apparaitre que la densite des etats au niveau de Fermi presente un minimum au voisinage des carbures du groupe IV. (auteur)

  13. Ressources à l'intention des bénéficiaires de subventions du CRDI ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Nous vous offrons des ressources et appuyons votre besoin d'apprendre, de vous épanouir et de réussir dans votre travail de chercheur. Notre équipe de Soutien à la recherche met au point des outils et aide les bénéficiaires. Vous devez être chercheur subventionné par le CRDI ou employé de ce dernier pour accéder à ...

  14. Ressources | CRDI - Centre de recherches pour le développement ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Grâce à la bibliothèque de ressources du CRDI, nous partageons nos résultats, fournissons un soutien aux chercheurs et offrons des outils aux acteurs du développement. Le CRDI soutient la recherche qui examine d'importants problèmes en matière de développement, trouve des solutions durables et enrichit les ...

  15. un_focus - La cogestion des ressources naturelles : Réduire la ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    M. Tyler était auparavant chef d'équipe du programme Gestion communautaire des ressources naturelles du CRDI en Asie. Dans ces fonctions, il a administré pendant sept ans un portefeuille de plus de 75 projets exécutés dans 12 pays. Il a obtenu un doctorat en aménagement urbain et régional de l'Université de la ...

  16. L'optimisation des ressources : risques et possibilités pour la ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    jmarcil

    il y a modulation des risques. De nombreux bailleurs de fonds investissent de façon soutenue dans la recherche au service du développement, reconnaissant les risques inévitables que cela comporte. Ils estiment souvent que la meilleure manière d'aborder l'optimisation des ressources consacrées à la recherche est de ...

  17. Gestion de la ressource en eau et conflits d'usage dans la commune ...

    African Journals Online (AJOL)

    L'approche méthodologique utilisée repose sur la recherche documentaire et les enquêtes de terrain pour lesquelles la population cible comprend les ménages, les autorités communales, les comités de gestion des ressources en eau, les agriculteurs, les éleveurs et les pêcheurs. Au total 270 ménages ont été enquêtés.

  18. Les SIG-P au service d'une gestion durable des ressources ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Les SIG-P au service d'une gestion durable des ressources naturelles et de la sécurité alimentaire en Afrique. Les pays africains ont besoin de données convenables aux fins de la formulation et de la mise en oeuvre de politiques et de stratégies de sécurité alimentaire systématiques et cohérentes. Ces pays disposent de ...

  19. Impact de la gestion des ressources humaines sur la survie des ...

    African Journals Online (AJOL)

    A partir d'un indice composite, l'indice de gestion des ressources humaines ... (iv) la gestion de la performance, et (v) la formation et le développement du ... Même si à cause du type d'étude quasi-expérimentale réalisée (avant-après), nous ne ... GRH d'une organisation doit aussi devenir un objectif chiffré du management.

  20. La divulgation de l’origine des ressources génétiques : une contribution du droit des brevets au développement durable?

    OpenAIRE

    Morin, Jean-Frédéric

    2005-01-01

    La Convention sur la diversité biologique prévoit que les avantages qui résultent de l'utilisation des ressources génétiques doivent être partagés avec les fournisseurs de ces ressources. Pour faciliter l’atteinte de cet objectif et exercer un suivi sur les transferts de ressources génétiques, un nombre croissant de pays imposent aux déposants de divulguer dans leurs demandes de brevets l’origine géographique des ressources génétiques utilisées pour développer l’invention revendiq...

  1. Electronic analogue simulator of radio cardiograms; Simulateur analogique electronique de radiocardiogrammes

    Energy Technology Data Exchange (ETDEWEB)

    Roux, G; Lansiart, A; Vernejoul, P de; Kellershohn, C [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1967-07-01

    The various parameters of the heart pump and of the blood circulation can be determined by radio-cardio-graphical techniques. The curves thus obtained can be more easily used in radiocardiography if the electronic analogue simulator described here is employed. The experimental and simulated radio-cardiograms are made to coincide by varying the electrical parameters of the simulator. Using simple charts it is possible to obtain directly the actual original physiological parameters from these electrical parameters. Some examples are given showing the excellent accuracy obtained in the determination of ejection indices by the simulator. (authors) [French] Les differents parametres de la pompe cardiaque et de la circulation sanguine peuvent etre determines par les techniques de radiocardiographie. L'exploitation des courbes obtenues en radiocardiographie est rendue plus aisee par l'utilisation du simulateur analogique electronique presente ici. Le radiocardiogramme experimental et le radiocardiogramme simule sont superposes en agissant sur les parametre electriques du simulateur. Par l'utilisation d'abaques simples, ces parametres electriques permettent de retrouver directement les parametres reels d'origine physiologique. Quelques exemples sont donnes montrant l'excellente precision obtenue dans la determination des indices d'ejection a l'aide du simulateur. (auteurs)

  2. Ressources vegetales de la foret classee de la lama et alimentation ...

    African Journals Online (AJOL)

    L'étude s'est déroulée dans la forêt classée de la Lama située entre 6°55-7°00N et 2°04-2°12 E. Elle a permis de mettre en exergue la diversité et la densité des ressources forestières alimentaires consommées par les populations des villages Holli et Fon vivant dans cette forêt. Au total, 45 espèces végétales sont ...

  3. Hybridation de la ressource humaine dans les associations : déterminants et effets.

    OpenAIRE

    Gontier , Patricia; Dansac , Christophe; Vachée , Cécile

    2014-01-01

    International audience; À l’image de la multiplicité des rôles que peuvent tenir les associations et autres organisations non orientées vers le profit dans nos sociétés, les ressources humaines impliquées dans les associations ou autres organisations non orientées vers le profit sont multiples. Dans leurs motivations, leurs compétences, et leurs parcours, les individus qui contribuent à ces organisations sont très différents. Parmi les bénévoles, on peut ainsi dissocier ceux qui administrent ...

  4. Aide à la décision en agriculture et gestion des ressources naturelles : note introductive

    OpenAIRE

    Jallas , Eric; Crétenet , Michel

    2003-01-01

    International audience; L'aide à la décision n'a pas pour but de se substituer aux décideurs en leur proposant des solutions "toutes faites". Elle cherche plutôt à les éclairer et à les guider vers des décisions dont ils conservent la responsabilité. Dans le domaine agricole et dans celui de la gestion des ressources naturelles, il existe aujourd'hui de nombreux outils d'aide à la décision. Les systèmes experts utilisent une base de connaissances afin de fournir des solutions, équivalentes à ...

  5. Impacts de l'exploitation artisanale de l'or sur les ressources ...

    African Journals Online (AJOL)

    L'exploitation de l'or est devenue ces deux dernières années l'activité principale de la population de Kéméni, une localité située dans la Préfecture de Tchaoudjo (Région Centrale du Togo). La présente étude a identifié l'impact de cette activité sur les ressources naturelles. L'approche méthodologique s'est basée sur des ...

  6. L'eau en Afrique, les paradoxes d'une ressource très convoitée

    International Development Research Centre (IDRC) Digital Library (Canada)

    développement, lie la situation de sous développement du continent africain par rapport à la mauvaise répartition de cette ressource hydrique sur le continent. 4. Karen Franken (sous la direction de) «L'irrigation en Afrique en chiffre. », Enquêtes AQUASTAT, FAO 2005,. 5. Analyse Multidisciplinaire de la mousson africaine.

  7. French achievements in the field of nuclear electronics; Realisations francaises dans le domaine de l'electronique nucleaire

    Energy Technology Data Exchange (ETDEWEB)

    Doireau, M; Fabre, R; Guillon, H; Guyot, C [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1958-07-01

    Nuclear electronic equipment used by the french Atomic Energy Commission has been developed, with an increasing participation of the radioelectric industry (manufacture under AEC license, contracts for prototypes). The equipment for general use has been standardized and satis the technical specification sheets in which are specified more particularly, the conditions for construction, the choice of the spare parts and the conditions for acceptance by the french AEC at factory. The electronic equipment is classified in nine classes, and a brief description of the principal instruments is given in each class. The reliability of the equipment in use is satisfactory, as it is shown by the mean frequency of faults per 1000 hours operation. (author)Fren. [French] L'appareillage d'electronique nucleaire utilise au Commissariat a l'Energie atomique fran is a ete developpe en demandant un concours de plus en plus important a l'industrie radioelectrique (fabrications sous licence CEA, marches de prototypes, etc...). Le materiel d'emploi courant a ete standardise et repond aux specifications de cahiers des charges ou sont precises en particulier les conditions de realisation du materiel, le choix des pieces detachees et les conditions de recette en usine. L'appareillage electronique est classe en neuf rubriques et une description sommaire des principaux appareils est donnee dans chacune des rubriques. La tenue en service du materiel est satisfaisante, ainsi que le montre la frequence moyenne des pannes observees par 1000 heures de fonctionnement. (auteur)

  8. Metoder til kortlægning og måling af fysiske ressourcer

    DEFF Research Database (Denmark)

    Nielsen, Niels Christian

    2010-01-01

    for det. Diskussionen gik, som den nu skal, på kryds og tværs af temaer og definitioner, men jeg vil her afgrænse mig fra opgørelser af de sociale, erhvervsmæssige og økonomiske ressourcer i et lokalområde, som de to andre oplægsholdere har beskrevet. I oplægget til workshoppen udfoldedes ideen om, at en...... kort - og efterfølgende observere og sammentælle. At det ikke er helt så enkelt i virkeligheden, kommer næppe som den store overraskelse, men jeg vil i det følgende prøve at reflektere over dels hvad det egentlig vil sig at kortlægge i og omkring et lokalsamfund og dels hvilke informationer som man kan...

  9. Réseaux, trajectoires et ressources de mobilités

    Directory of Open Access Journals (Sweden)

    Jean-Baptiste Meyer

    2014-06-01

    Full Text Available La thèse de Sabrina Marchandise consiste à « démontrer en quoi et comment les mobilités… » participent de la création territoriale, « dans des temps courts » en soulevant trois hypothèses : celles de ressources de mobilité différenciées utilisées par les acteurs (ici étudiants, de réseaux élargis et interconnectés à travers ces mobilités provisoires, et de la territorialisation de ces réseaux. La problématique est géographique mais le cadre théorique et méthodologique convoque volontiers d’a...

  10. Le FOS: une évaluation des ressources pédagogiques en ligne

    Directory of Open Access Journals (Sweden)

    Nuria Rodríguez

    2007-04-01

    Full Text Available Conscients de l’importance croissante que revêtent la formation en distanciel et par voie de conséquence les méthodes, outils et activités articulées autour d’un apprentissage autonome, cette étude se propose d’évaluer l’ensemble des ressources pédagogiques en ligne mises à disposition de l’internaute apprenant. Comme les contenus interactifs et multimédia concernant le FLE (français langue étrangère sont innombrables, nous nous sommes centrés sur le français de spécialité (FOS: français sur objectifs spécifiques, en particulier, le français des affaires et du tourisme. Notre objectif étant de compléter un travail précédent portant sur l’évaluation des sites FOS, de nouveaux critères ont été considérés pour une utilisation optimale des ressources en jeu. Il s’avère qu’une bonne combinaison des outils pédagogiques disponibles sur Internet pourrait être une bonne option pour les apprenants du français des affaires, alors que les outils de formation interactive concernant le français du tourisme demeurent insuffisants pour garantir un apprentissage adéquat de cette langue spécifique.

  11. Ressources pétrolières pour le XXe siecle : quel avenir ? Oil Ressources for the 21st Century: Constraints and Outlook

    Directory of Open Access Journals (Sweden)

    Alazard N.

    2006-11-01

    Full Text Available Les réserves prouvées d'hydrocarbures liquides sont aujourd'hui évaluées, suivant les sources, entre 950 et 1 000 milliards de barils. Leur durée de vie, au rythme actuel de la production mondiale, est d'environ 41 à 45 ans, soit bien supérieure à celles qui étaient couramment données en 1970 et 1980. Toutefois, cette abondance des ressources ne garantit pas obligatoirement la sécurité des approvisionnements pétroliers pour tous les pays. Il importe de souligner que les réserves pétrolières sont géographiquement inégalement réparties et que réserves et productions sont actuellement le fait des champs géants (champs ayant plus de 500 millions de barils de réserves initiales. Si l'approvisionnement pétrolier semble assuré pour les trente à quarante années à venir, quelles sont les perspectives au-delà de 2020-2030 ? L'augmentation des réserves prouvées au cours des dix à vingt années qui viennent de s'écouler n'est qu'apparente. Cet accroissement, après 1986, est essentiellement dû à des révisions et à des extensions plutôt qu'à de nouvelles découvertes. L'article, présenté ici, s'efforce d'inventorier et d'évaluer quelles pourraient être les nouvelles sources de pétrole : bruts conventionnels (brut récupérable compte tenu d'un prix au baril de l'ordre de 20 US$ et d'un taux de récupération voisin de 30 % restant à découvrir, ressources en huile issues d'une amélioration du taux de récupération, ressources résultant de l'exploitation de zones nouvelles (l'offshore profond, bruts de types non conventionnels tels que bruts extra-lourds, sables asphaltiques, huiles de schiste, et hydrocarbures liquides obtenus grâce aux méthodes de récupération assistée par voie chimique. The assessment of proven reserves of liquid hydrocarbons currently varies between 950 and 1 000 billion barrels, depending on the sources. The foreseeable lifetime, at the present rate of world production, is about 41 to

  12. Russian Arctic Petroleum Resources Ressources pétrolières de l’Arctique russe

    Directory of Open Access Journals (Sweden)

    Zolotukhin A.

    2011-12-01

    should be in place, like national standards and guidelines for Arctic resources development, stable, transparent and predictable law as a necessary precondition for massive investments in exploration and production and, not least, active involvement of foreign companies in development of Arctic resources that could bring along with investments an indispensible competence and experience, available technology and Health, Safety and Environment (HSE principles. Development of oil and gas fields in the arctic seas located few hundreds miles from shore is according to expert opinion the most challenging project in the world. Without international cooperation, coordination of all activities and use of modern and proven technologies for production of hydrocarbons, their transport, efficient safety and environmental protection tools the realization of such a project would be questionable. Le plateau continental arctique est considéré comme la zone comportant le potentiel inexploré le plus important tant en termes d’huile et de gaz qu’en ressources en hydrocarbures non conventionnels tels que les hydrates de gaz. En dépit d’une vision courante selon laquelle l’Arctique possède des ressources abondantes en hydrocarbures, des débats se poursuivent sur le potentiel énergétique de cette région. Les lignes directrices de telles discussions reposent sur la géopolitique, les questions environnementales, l’évaluation et la délimitation des ressources arctiques, la technologie disponible pour le succès de leur exploitation et les perspectives d’évolution de la demande en énergie. La partie russe est reconnue comme étant la plus importante concernant les ressources en huile et gaz des nations arctiques. Toutefois, le manque d’informations et de données géologiques disponibles engendre une incertitude sur le rôle futur de l’Arctique russe comme principal fournisseur d’énergie dans la seconde partie du XXIe siècle. Une incertitude supplémentaire repose

  13. Analysis of electronic circuits using digital computers; L'analyse des circuits electroniques par les calculateurs numeriques

    Energy Technology Data Exchange (ETDEWEB)

    Tapu, C [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1968-07-01

    Various programmes have been proposed for studying electronic circuits with the help of computers. It is shown here how it possible to use the programme ECAP, developed by I.B.M., for studying the behaviour of an operational amplifier from different point of view: direct current, alternating current and transient state analysis, optimisation of the gain in open loop, study of the reliability. (author) [French] Differents programmes ont ete proposes pour l'etude des circuits electroniques a l'aide des calculateurs. On montre comment on peut utiliser le programme ECAP, mis au point par I. B. M., pour etudier le comportement d'un amplificateur operationnel, a differents points de vue: analyse en courant continu, courant alternatif et regime transitoire, optimalisation du gain en boucle ouverte, etude de la fiabilite. (auteur)

  14. Quick electronics in the field of high energy physics; L'electronique rapide en physique de hautes energies

    Energy Technology Data Exchange (ETDEWEB)

    Meunier, R [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1958-07-01

    An extensive technical development of particle counting in the field of high energy physics near any large modern accelerator is a necessary condition for efficient work with its beams of particles. In this review article, the basic principles of more commonly used circuite described with special emphasis on the explanation of the limits of their use. (author)Fren. [French] L'utilisation efficace des faisceaux de particules produits par les grands accelerateurs modernes a rendu necessaire un progres des techniques de comptage et de mesure electronique. Cet article decrit les principes de fonctionnement des differents circuits les plus communement utilises et explique plus particulierement les raisons de leurs limites d'utilisation. (auteur)

  15. Electronic commutating equipment for the automatic recording of pulses; Ensemble commutateur electronique pour enregistrement automatique d'impulsions

    Energy Technology Data Exchange (ETDEWEB)

    Garnaud, P [Commissariat a l' Energie Atomique, Saclay (France).Centre d' Etudes Nucleaires

    1961-07-01

    This electronic selector allows to record six parted channels of pulses with only one automatic recorder type S.F.A.T. 57.3B. The numbers of pulses issuing from different counters or P.M. during a marc h time, are recorded on a tape of paper by one 'Elettrosumma 14 Olivetti' during the stop-time. (author) [French] Ce commutateur electronique permet d'enregistrer 6 voies separees d'impulsions avec un seul appareil d'enregistrement automatique type S.F.A.T. 57.3B. Les nombres d'impulsions provenant de differents compteurs ou P.M. pendant un temps de marche sont enregistres pendant l'arret des comptages sur une bande de papier par une machine imprimante 'Elettrosumma 14 Olivetti'. (auteur)

  16. An electronic probe micro-analyser. A linear scan device; Microanalyseur a sonde electronique. Dispositif de balayage lineaire

    Energy Technology Data Exchange (ETDEWEB)

    Kirianenko, A; Maurice, F [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1963-07-01

    The Castaing electronic probe micro-analyser makes possible static analysis at successive points. For two years this apparatus has been equipped by its constructor with an automatic device for surface scanning. In order to increase the micro-analyser's efficiency a 'linear' scan device has been incorporated making it possible to obtain semi-quantitative analyses very rapidly. (authors) [French] Le microanalyseur a sonde electronique de Castaing permet l'analyse statique en des points successifs. Depuis deux ans, cet appareil a ete equipe par son constructeur d'un dispositif de balayage automatique 'surface'. Afin d'augmenter l'efficacite du microanalyaeur, on a adapte un dispositif de balayage 'lineaire' qui permet d'obtenir tres rapidement des analyses semi-quantitative. (auteurs)

  17. L'Empowerment au coeur des bouleversements induits par les TIC dans la gestion des ressources humaines

    OpenAIRE

    Blavier, André

    2012-01-01

    Observer l’influence des TIC (Technologies de l’Information et de la Communication” sur les ressources humaines à la lumière du seul débat “pour ou contre les réseaux sociaux dans l’entreprise ou l’organisation ?” est une approche bien trop restrictive. Les défis relatifs à l’évolution des ressources humaines s’inscrivent dans une perspective plus large, celle d’un environnement numérique global. Comme l’a souligné le rapport “Digital Economy Rankings 2010” d’IBM en collaboration avec l’Econ...

  18. Observations on the electronic equipment employed for making measurements on the pile G1; Observations sur le materiel electronique utilise pour les mesures sur la pile G1

    Energy Technology Data Exchange (ETDEWEB)

    Ailloud, J; Belin, P; Meunier, A; Tarabella, A [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1957-07-01

    The electronic apparatus employed during the manipulations carried out on the pile G1 is briefly described, with the aim of putting on record the inconveniences encountered in the course of the operation of this equipment. (author) [French] On decrit succinctement l'appareillage electronique utilise durant les manipulations effectuees sur la pile G1, dans le but de noter les inconvenients rencontres au cours de l'exploitation de cet appareillage. (auteur)

  19. Hilfe oder Hindernis? Meinungen finnischer Sprachstudierender über Mehrsprachigkeit als Ressource beim Deutschlernen

    Directory of Open Access Journals (Sweden)

    Sabine Grasz

    2017-10-01

    Full Text Available Der Fremdsprachenunterricht in Finnland befindet sich gerade in einer Umbruchphase, denn mit der Einführung neuer Lehrpläne im Jahr 2016 werden Verfahren der Mehrsprachigkeitsdidaktik in Zukunft eine zentrale Rolle spielen. In diesem Beitrag wird untersucht, ob und wie finnische Universitätsstudierende, die selbst von einer eher monolingual ausgerichteten Lerntradition geprägt sind, ihr mehrsprachiges Repertoire als Ressource beim Lernen weiterer Fremdsprachen sehen. Zu diesem Zweck wurde eine Befragung unter Lehramtsstudierenden der Fächer Anglistik und Skandinavistik, die Germanistik als Nebenfach studieren möchten, durchgeführt. Die Analyse zeigt, dass die Studierenden zwar mehrheitlich positive Einstellungen gegenüber Mehrsprachigkeit aufweisen, dass es aber Entwicklungsbedarf im Hinblick auf Sprachbewusstheit, multilinguale Fähigkeiten und bei den Einstellungen gegenüber Sprachmischungen gibt. Foreign language education in Finland is currently undergoing a period of change, as the introduction of new curricula in 2016 will lead to a central role of multilingualism in teaching. This article examines whether and how Finnish university students, who themselves were influenced by a more monolingual learning tradition, consider their multilingual repertoire as a resource for learning other foreign languages. For this purpose, a survey was conducted among teacher students of English and Swedish, who would like to study German as a minor. The analysis shows that while the majority of students have positive attitudes towards multilingualism, there is a need for development in terms of language awareness, multilingual skills, and attitudes towards language mixes.

  20. La gestion des ressources renouvelables: vers un gestion patrimoniale des écosystèmes

    Directory of Open Access Journals (Sweden)

    2004-01-01

    Full Text Available Cet article analyse et critique les approches de gestion biologique et économique des ressources naturelles traditionnellement appliquées. Sont présentées des alternatives à ces modèles, basées sur l’institutionnalisme et l’approche de gestion patrimoniale. Ce cadre théorique devrait favoriser la mise en œuvre d’une gestion viable des écosystèmes. Este artículo analiza y critica los modelos de gestión biológica y económica de recursos naturales tradicionalmente aplicados. Se presentan alternativas a estos modelos, basados en el institucionalismo y el manejo patrimonial, los que constituirían un marco teórico que viabilice la gestión de recursos naturales en los ecosistemas. This paper analyses and criticizes traditional approaches to biological and economic management of natural resources. Alternative approaches are presented based on institutionalism and heritage management these constitute a theoretical framework for the implementation of appropriate natural resource use in ecosystems.

  1. Politique d’acquisitions foncières et protection de la ressource en eau

    Directory of Open Access Journals (Sweden)

    LAMOUREUX, Ludovic

    2016-05-01

    Full Text Available La préservation des eaux souterraines et des rivières est un enjeu majeur pour les opérateurs en charge de l'alimentation en eau potable sur un territoire. Eau de Paris, l'opérateur public qui produit et distribue l'eau dans Paris mobilise de nombreux dispositifs pour protéger et restaurer la qualité de l'eau. Depuis plus de vingt ans, il conduit notamment une politique de maîtrise foncière des terrains ruraux situés dans les zones vulnérables des aires d’alimentation des captages, qui vise principalement à limiter les risques de pollution des nappes, mais également à servir de modèle et de levier pour des pratiques agricoles favorisant la préservation de la ressource en eau. Cet article nous présente ici l'intérêt d'une telle démarche, mais également les difficultés rencontrées par l'opérateur pour mener cette politique d'acquisition foncière en milieu rural.

  2. Patrimoine et territoire, les nouvelles ressources du développement

    Directory of Open Access Journals (Sweden)

    Pierre-Antoine Landel

    2009-01-01

    Full Text Available La démarche présentée ici s'inscrit dans le cadre théorique actuellement travaillé autour de la notion de ressource territoriale. Elle propose une relecture des différents travaux engagés sur cette notion, tente d'y apporter quelques éléments complémentaires et confronte ces propositions théoriques à une première analyse des dossiers déposés par les 342 territoires ayant répondu à l'appel à projet Pôles d'excellence rurale lancé par la Diact en décembre 2005. L’analyse des projets de développement permet au final de proposer une interprétation de la notion de développement durable. Plutôt que de constituer une notion autonome, il s’agirait en fait d’une forme intermédiaire entre un mode de développement productiviste et un mode de développement que nous qualifions de patrimonial.The initiative proposed here joins in the theoretical frame at present worked around the notion of territorial resource. It proposes a second reading of the various works engaged on this notion, tries to bring it some additional elements and confronts these theoretical propositions with a first analysis of the files deposited by the 342 territories having answered the call to project "Pôles d'excellence rurale" launched by the Interministerial Delegation for Territorial Planning and Competitiveness (DIACT in December, 2005. The analysis of the projects of development, allows in the end to propose an interpretation of the notion of sustainable development. Rather than to constitute an autonomous notion, it would be in fact about an intermediate between a productivist mode of development and a mode of development which we consider as patrimonial.

  3. Réserves, ressources et disponibilités mondiales en hydrocarbures World Hydrocarbon Reserves, Resources and Availabilities

    Directory of Open Access Journals (Sweden)

    Bois C.

    2006-11-01

    Full Text Available Les réserves prouvées en hydrocarbures conventionnels s'élèvent dans le monde à 90 milliards de tonnes de pétrole et 78 000 milliards de m3 de gaz, ce qui représente respectivement 30 et 50 ans au taux actuel de production. Les réserves et ressources supplémentaires à découvrir peuvent être considérées comme 2,3 à 2,4 plus importantes mais ces valeurs sont entachées d'une forte incertitude. II existe de grandes ressources en hydrocarbures non conventionnels, mais elles sont coûteuses à mettre en oeuvre et demandent surtout des investissements considérables. On peut prévoir que la production mondiale de pétrole atteindra son maximum vers 1990. Proven reserves of conventional hydrocarbons in the world amount to 90 billion tons of oil and 78 000 billion cubic meters of gas, respectively representing 30 and 50 years of supply at the present rate of production. Further reserves and resources yet to be discovered may be considered to be 2. 3 to 2. 4 times greater, but there is a high degree of uncertainty in these figures. Extensive resources of unconventional hydrocarbons exist, but they are costly to implement and, above all, require considerable investments. World petroleum production can be predicted to reach its maximum around 1990.

  4. Les ressources en charbon de l'Amérique du Sud Coal Resources in South America

    Directory of Open Access Journals (Sweden)

    Alvarado B.

    2006-10-01

    Full Text Available L'Amérique du Sud en général est mal pourvue en ressources de charbon puisqu'elle ne représente que 0,5 % des ressources mondiales. Cependant, avec la crise actuelle de l'énergie et le développement rapide de l'industrie sidérurgique locale, tous les pays possesseurs de charbon s'appliquent à faire des recherches tendant à évaluer à sa juste valeur le potentiel charbonnier comme la source d'énergie la plus traditionnelle et la matière première irremplaçable pour la production du coke métallurgique. Dans cet article, il sera question des ressources d'Argentine, du Brésil, du Chili, de Colombie, du Pérou et du Venezuela, seuls pays qui recèlent des réserves reconnues. Les principaux gisements sud-américains se rencontrent dans les sédiments gondwaniens, crétacés, et certains probablement déposés dans des milieux deltaïques et lacustres, avec majorité de charbons bitumineux et sub-bitumineux de haute volatilité. La Colombie est le pays qui a les plus grandes ressources et toutes les catégories de charbon y compris ceux cokéfiables. Du fait que les diverses évaluations nationales ne sont pas comparables, compte tenu de ce qu'elles sont basées sur des concepts géologiques et technologiques avec des niveaux de pronostics et de certitudes variables, l'auteur, pour éviter une plus grande confusion, n'exprimera pas la grandeur des ressources en chiffres absolus. Generally speaking, South America is poor in coal resources, with only 0,50% of the world's supplies. Nonetheless, with the present energy crisis and the rapid development of the local steel industry, all countries possessing coal deposits are undertaking research to evaluate accurately their potential resources of coal, the most traditional energy source and the indispensable raw material for the production of foundry coke. In this paper will be discussed the resources of those South Americon countries known to have coal reserves: Argentina, Brazil, Chile

  5. Electronic diffraction study of the chlorination of nickel; Etude par diffraction electronique de la chloruration du nickel

    Energy Technology Data Exchange (ETDEWEB)

    Vigner, D [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1969-07-01

    A study has been made of the chlorination of the (100), (110) and (111) crystal faces of nickel using high energy electron diffraction and electron microscopy. Two methods have been used: bombardment with chlorine ions having an energy of between 10 and 30 keV, and direct chlorination in a diffractor at pressures of about 10{sup -4} torr. It has thus been possible to show the very special properties of nickel chloride (CdBr{sub 2} type, space group R 3-bar m) which is always formed along the (0001) plane, whatever the orientation of the substrate. It has also been possible to attain the metal-halide interface and to show the existence of two-dimensional chemisorbed films which are ordered or disordered according to the crystal orientation. (author) [French] La chloruration des faces (100) (110) et (111) du nickel a ete etudiee par diffraction des electrons de haute energie et par microscopie electronique. Deux methodes ont ete utilisees: le bombardement avec des ions chlore ayant une energie comprise entre 10 et 30 keV, et la chloruration directe dans un diffracteur pour des pressions de l'ordre de 10{sup -4} torr. Ainsi ont ete mises en evidence les proprietes tres particulieres du chlorure de nickel (type CdBr{sub 2}, groupe spatial R 3-bar m) qui s'accole toujours suivant le plan (0001), quelle que soit l'orientation du substrat. Il a ete egalement possible d'atteindre l'interface metal-halogenure et de montrer l'existence de couches chimisorbees bidimensionnelles, ordonnees ou desordonnees suivant l'orientation cristalline etudiee. (auteur)

  6. Prospective des ressources face à la consommation The Outlook for Resources in the Face of Consumption

    Directory of Open Access Journals (Sweden)

    Rutman G.

    2006-11-01

    Full Text Available Cette étude prospective tient compte des données politiques et économiques portées à notre connaissance en septembre 1979. Des événements nouveaux, aujourd'hui imprévisibles, survenant d'ici juillet 1980, pourraient en modifier considérablement certaines des conclusions qui sont rappelées brièvement ici : - le problème d'approvisionnement en hydrocarbures n'est pas un problème d'existence physique des ressources ; - l'offre, compte tenu du contexte socio-politique et de la répartition géogra-phique des hydrocarbures, se situera dans les dix prochaines années très près du niveau actuel des 63 millions de bbl/d ; - les hypothèses faites sur la demande sont plus hasardeuses, l'une d'entre elles (W. J. Levy l'estime pour 1990 à 68,8 millions de bbl/d ; - l'équilibre offre/demande n'est pas réalisé à court terme et il faut dès maintenant, envisager un équilibre de légère pénurie à moyen et long terme ; - la contribution du gaz naturel et des autres hydrocarbures au rétablissement de l'équilibre subit divers handicaps de coûts, de difficulté de transport oude délais de mise en oeuvre ; - ceci implique que le prix du brut ne peut que croître en valeur réelle et que l'exploration-production et le développement d'hydrocarbures non conventionnels constituent le challenge majeur de la prochaine décennie ; - la solution à moyen terme passe par le développement des productions des pays de l'OPEP à condition de leur offrir des développements sociaux et industriels compatibles avec leurs besoins réels. This glance into the future takes into considaration political and economic data brought to our attention in September 1979. New and unpredictable events occurring between now and July 1980 could make considerable changes in the conclusions briefly summed up here: - the problem of hydrocarbon supplies is not a problem of the physical existence of resources; - the supply, in the light of the socio-political context and

  7. Dynamique des ressources naturelles dans le Parc national de Manda: Cartographie et analyse pour le Développement durable

    Science.gov (United States)

    Ballah Solkam, Rosalie; Médard, Ndoutorlengar

    2018-05-01

    Au Tchad, le réseau d'aires protégées couvre près de 10,2% de la surface du pays et reste globalement représentatif de toute la diversité des écosystèmes de la région. Cependant, ce réseau n'est pas constitué d'écosystèmes intacts car de nombreuses altérations y ont été apportés (certaines espèces sont déjà au seuil critique d'extinction (Addax, gazelle dama, lamantin), voire ont disparu (Rhinocéros noir et blanc, Oryx)) surtout dans les parcs nationaux. Ce qui nous amène à nous interroger sur la dynamique des ressources naturelles et le degré de conservation du parc national de Manda? Une évaluation de la diversité biologique et des ressources hydrographiques de 1951 à 1999 sur la base de la bibliographie existante, de la carte topographique de 1956, des images satellitaires Landsat 5 et 7 TM et ETM+ de 2 périodes (1986, 1999), complétée par des interviews semi-structurés et des transects sur le terrain, permettra de mieux appréhender la dynamique des ressources et les actions de conservation de la biodiversité réalisées à cet effet. Les résultats montrent une dynamique progressive de la faune de 1951 à 1970, puis une dynamique régressive de 1970 à 1989. Après cette tumultueuse période, un repeuplement du parc s'opère de 1989 à 2002. Par contre, la flore est relativement bien conservée avec quelques cours d'eau, des mares, champs et plantations. Et cela grâce aux multiples projets de conservation de la biodiversité. La promotion de l'écotourisme serait une alternative au développement durable de ce parc.

  8. Etude de la formation de resonances electroniques et de leur role dans la fragmentation neutre de molecules d'interet biologique

    Science.gov (United States)

    Lepage, Martin

    1998-12-01

    Cette these est presentee a la Faculte de medecine de l'Universite de Sherbrooke en vue de l'obtention du grade de Ph.D. en Radiobiologie. Elle contient des resultats experimentaux enregistres avec un spectrometre d'electrons a haute resolution. Ces resultats portent sur la formation de resonances electroniques en phase condensee et de differents canaux pour leur decroissance. En premier lieu, nous presentons des mesures d'excitations vibrationnelles de l'oxygene dilue en matrice d'argon pour des energies des electrons incidents de 1 a 20 eV. Les resultats suggerent que le temps de vie des resonances de l'oxygene est modifie par la densite d'etats d'electrons dans la bande de conduction de l'argon. Nous presentons aussi des spectres de pertes d'energie d'electrons des molecules de tetrahydrofuranne (THF) et d'acetone. Dans les deux cas, la position en energie des pertes associees aux excitations vibrationnelles est en excellent accord avec les resultats trouves dans la litterature. Les fonctions d'excitation de ces modes revelent la presence de plusieurs nouvelles resonances electroniques. Nous comparons les resonances du THF et celles de la molecule de cyclopentane en phase gazeuse. Nous proposons une origine commune aux resonances ce qui implique qu'elles ne sont pas necessairement attribuees a l'excitation des electrons non-apparies de l'oxygene du THF. Nous proposons une nouvelle methode basee sur la spectroscopie par pertes d'energie des electrons pour detecter la production de fragments neutres qui demeurent a l'interieur d'un film mince condense a basse temperature. Cette methode se base sur la detection des excitations electroniques du produit neutre. Nous presentons des resultats de la production de CO dans un film de methanol. Le taux de production de CO en fonction de l'energie incidente des electrons est calibre en termes d'une section efficace totale de diffusion des electrons. Les resultats indiquent une augmentation lineaire du taux de production de

  9. Réglementation et ressources naturelles : l’exemple de la forêt en Comtat Venaissin

    OpenAIRE

    Leroy, Nicolas

    2009-01-01

    À travers l’exemple de la forêt dans le Comtat Venaissin et la Principauté d’Orange voisine, sont approchées les réglementations visant à assurer une gestion raisonnée de la ressource bois. À la fin du Moyen Âge, la prise de conscience de la raréfaction des forêts est incontestable dans la région. Plusieurs seigneurs et communautés élaborent alors des mesures visant à concilier conservation et exploitation indispensable aux villageois. Celles-ci vont de l’interdiction assez stricte d’accès et...

  10. Electron microscope observation of single - crystalline beryllium thin foils; Observation de lames minces monocristallines de beryllium en microscopie electronique

    Energy Technology Data Exchange (ETDEWEB)

    Antolin, J; Poirier, J P; Dupouy, J M [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1965-07-01

    Thin foils prepared from single crystalline beryllium simples deformed at room temperature, have been observed by transmission electron microscopy. The various deformation modes have been investigated separately, from their early stages and their characteristic dislocation configurations have been observed. Basal slip is characterized at is outset by the presence of numerous dipoles and elongated prismatic loops. More pronounced cold work leads to the formation of dislocation tangles and bundles which eventually give a cellular structure. Prismatic slip begins by the cross-slip of dislocations from the basal plane into the prismatic plane. A cellular structure is equally observed in heavily deformed samples. Sessile dislocations have been observed in twin boundaries; they are produced by reactions between slip dislocations and twin dislocations. Finally, the study of samples quenched from 1100 deg. C and annealed at 200 deg. C has shown that the observed loops lie in prismatic planes and have a Burgers vector b 1/3<1 1 2-bar 0>. (authors) [French] On a observe en microscopie electronique par transmission des lames minces tirees d'eprouvettes monocristallines de beryllium deformees a l'ambiante. On a etudie separement les differents modes de deformation a partir de leur stade elementaire en observant les configurations de dislocations caracteristiques. Le glissement basal est caracterise a son debut par la presence de nombreux dipoles et de boucles prismatiques allongees. Des ecrouissages plus forts conduisent a la formation d'echeveaux et de gerbes qui finissent par donner une structure cellulaire. Le glissement prismatique debute par le glissement des dislocations hors du plan de base dans les plans prismatiques. On trouve egalement une structure cellulaire pour de forts ecrouissages. Dans les joints de macle, on a observe des dislocations sessiles formees par la reaction entre dislocations de macle et dislocations de glissement. Enfin l'etude d

  11. Fumiers de bovins, une ressource à fort potentiel pour la filière de méthanisation en France ?

    Directory of Open Access Journals (Sweden)

    DEGUEURCE, Axelle

    2016-02-01

    Full Text Available En France, la méthanisation agricole représente l'un des principaux leviers d’action pour atteindre les objectifs « biogaz » dans la production d’énergies renouvelables. L'agriculture génère en effet d’abondantes ressources exploitables pour la production de biogaz par méthanisation. En croisant différentes bases de données de la statistique agricole et les pratiques d’élevage recensées sur le territoire français, les auteurs nous proposent ici d'évaluer le potentiel du gisement énergétique des effluents de bovins, et d'analyser les conditions pour mieux mobiliser cette ressource sur le territoire.

  12. Electron microscope study of vacancy clusters produced by quenching in magnesium; Etude par microscopie electronique des amas de lacunes crees par trempe dans le magnesium

    Energy Technology Data Exchange (ETDEWEB)

    Levy, V; Espinasse, J; Mairy, C; Hillairet, J [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1969-07-01

    Vacancy clustering in quenched magnesium has been studied by transmission electron microscopy. The nature of the vacancy loops observed, seems to depend essentially on the impurity content of the metal; this effect can be attributed to a variation of the stacking fault energy of magnesium due to impurities. (authors) [French] On a etudie par microscopie electronique en transmission les defauts crees par trempe dans le magnesium. Un effet considerable des impuretes du metal sur la nature des boucles obtenues par condensation de lacunes a ete mis en evidence; cet effet semble s'expliquer de facon satisfaisante par un abaissement de l'energie de faute d'empilement du magnesium du aux impuretes. (auteur)

  13. Progressive and resonant wave helices application to electron paramagnetic resonance; Helices a ondes progressives et resonnantes application a la resonance paramagnetique electronique

    Energy Technology Data Exchange (ETDEWEB)

    Volino, F [Commissariat a l' Energie Atomique, Grenoble (France). Centre d' Etudes Nucleaires

    1969-07-01

    We show that helices can be used as resonant systems. Their properties are theoretically and experimentally studied. We describe resonant helices for electron paramagnetic resonance in X-band and develop a comparison between their sensitivity and the sensitivity of a normal resonant cavity. For cylindrical samples less than 3 mm diameter, the helix is more sensitive and can produce more intense microwave magnetic fields. (author) [French] Il est montre que les helices peuvent etre utilisees comme systeme resonnant. Leurs proprietes sont discutees theoriquement et experimentalement. Des helices resonnantes en bande X pour la resonance paramagnetique electronique sont decrites et leur sensibilite est comparee a celle des cavites resonnantes. Pour des echantillons cylindriques de moins de 3 mm de diametre, l'helice est plus sensible et peut produire des champs magnetiques hyper fins plus intenses. (auteur)

  14. Magnetic rotational polarisation in plasmas. Application to the measurement of electronic density; Polarisation rotatoire magnetique dans les plasmas. Application a la mesure de la densite electronique

    Energy Technology Data Exchange (ETDEWEB)

    Consoli, Terenzio; Dagai, Michel [Commissariat a l' energie atomique et aux energies alternatives - CEA (France)

    1960-07-01

    The rotation of a linearly polarised wave passing through a layer of plasma is determined. A network of curves enables these results to be applied to the electronic density measurement in a plasma during its evolution. Reprint of a paper published in Comptes rendus des seances de l'Academie des Sciences, t. 250, p. 1010-1012, sitting of 8 February 1960 [French] On determine la rotation d'une onde polarisee lineairement, traversant une couche de plasma. Un reseau de courbes permet d'appliquer ces resultats a la mesure de la densite electronique d'un plasma en evolution. Reproduction d'un article publie dans les Comptes rendus des seances de l'Academie des Sciences, t. 250, p. 1010-1012, seance du 8 fevrier 1960.

  15. Progressive and resonant wave helices application to electron paramagnetic resonance; Helices a ondes progressives et resonnantes application a la resonance paramagnetique electronique

    Energy Technology Data Exchange (ETDEWEB)

    Volino, F. [Commissariat a l' Energie Atomique, Grenoble (France). Centre d' Etudes Nucleaires

    1969-07-01

    We show that helices can be used as resonant systems. Their properties are theoretically and experimentally studied. We describe resonant helices for electron paramagnetic resonance in X-band and develop a comparison between their sensitivity and the sensitivity of a normal resonant cavity. For cylindrical samples less than 3 mm diameter, the helix is more sensitive and can produce more intense microwave magnetic fields. (author) [French] Il est montre que les helices peuvent etre utilisees comme systeme resonnant. Leurs proprietes sont discutees theoriquement et experimentalement. Des helices resonnantes en bande X pour la resonance paramagnetique electronique sont decrites et leur sensibilite est comparee a celle des cavites resonnantes. Pour des echantillons cylindriques de moins de 3 mm de diametre, l'helice est plus sensible et peut produire des champs magnetiques hyper fins plus intenses. (auteur)

  16. Mechanics and electronics as auxiliary techniques in nuclear research and exploitation; Mecanique et electronique auxiliaires de la recherche et de l'exploitation nucleaire

    Energy Technology Data Exchange (ETDEWEB)

    Weill, J. [Commissariat a l' energie atomique et aux energies alternatives - CEA, Centre d' Etudes nucleaires de Saclay, Departement Electronique, Groupe Controle des Reacteurs (France)

    1959-07-01

    Electronics and mechanics form the basic techniques used in the field of measurement and control in nuclear physics experiments, and in nuclear machine installations. The delegate describes some instruments typical of the use of these techniques in the fields of calculation, detection, amplification and nuclear Installations. Reprint of a paper published in 'Bulletin S.F.M.' n. 25 (3. quarter 1957) [French] L'electronique et la mecanique constituent les techniques de base utilisees clans le domaine des mesures et du controle effectues dans les experiences de physique nucleaire et dans les installations des engins nucleaires. Le Conferencier decrit plusieurs appareils caracteristiques de l'emploi de ces techniques dans les domaines du calcul, des detecteurs, de l'amplification et des lnstallations nucleaires. Reproduction d'un article publie dans le 'Bulletin S.F.M.' n. 25 (3e trimestre 1957)

  17. Contribution to the study of molecular movements in cyclohexane by electron spin resonance and electron-nuclear double resonance using a radical probe; Contribution a l'etude des mouvements moleculaires dans le cyclohexane par resonance paramagnetique electronique et double resonance electronique-nucleaire a l'aide d'une sonde radicalaire

    Energy Technology Data Exchange (ETDEWEB)

    Volino, F [Commissariat a l' Energie Atomique, Grenoble (France). Centre d' Etudes Nucleaires

    1969-07-01

    Solutions of stable free radicals of the nitroxide type have been studied as a function of temperature. In the plastic or globular state, the cyclohexane molecules have rapid rotational and diffusional movements. They transmit this movement to dissolved free radicals. Conversely, measurements by electron spin resonance of the absolute movement of the radicals, and by electron nuclear double resonance of their movement relative to the cyclohexane molecules give very precise methods for local analyses of the movement present in the cyclohexane matrix. The principle of these techniques makes up the 'radical probe method'. (author) [French] Des solutions de radicaux libres stables, du type nitroxyde dans le cyclohexane ont ete etudiees, en fonction de la temperature. Les molecules de cyclohexane, dans l'etat plastique ou globulaire, sont animees de mouvements rapides de rotation sur elles-memes et de diffusion. Elles transmettent leur mobilite aux radicaux libres dissous. Reciproquement, la mesure du mouvement absolu des radicaux, a l'aide de la resonance paramagnetique electronique, et celle du mouvement relatif des radicaux et des molecules de cyclohexane par double resonance electronique-nucleaire, constituent des methodes tres precises pour analyser localement les mouvements presents dans la matrice de cyclohexane. Ce principe et ces techniques constituent la 'methode de la sonde radicalaire'. (auteur)

  18. Contribution to the study of molecular movements in cyclohexane by electron spin resonance and electron-nuclear double resonance using a radical probe; Contribution a l'etude des mouvements moleculaires dans le cyclohexane par resonance paramagnetique electronique et double resonance electronique-nucleaire a l'aide d'une sonde radicalaire

    Energy Technology Data Exchange (ETDEWEB)

    Volino, F. [Commissariat a l' Energie Atomique, Grenoble (France). Centre d' Etudes Nucleaires

    1969-07-01

    Solutions of stable free radicals of the nitroxide type have been studied as a function of temperature. In the plastic or globular state, the cyclohexane molecules have rapid rotational and diffusional movements. They transmit this movement to dissolved free radicals. Conversely, measurements by electron spin resonance of the absolute movement of the radicals, and by electron nuclear double resonance of their movement relative to the cyclohexane molecules give very precise methods for local analyses of the movement present in the cyclohexane matrix. The principle of these techniques makes up the 'radical probe method'. (author) [French] Des solutions de radicaux libres stables, du type nitroxyde dans le cyclohexane ont ete etudiees, en fonction de la temperature. Les molecules de cyclohexane, dans l'etat plastique ou globulaire, sont animees de mouvements rapides de rotation sur elles-memes et de diffusion. Elles transmettent leur mobilite aux radicaux libres dissous. Reciproquement, la mesure du mouvement absolu des radicaux, a l'aide de la resonance paramagnetique electronique, et celle du mouvement relatif des radicaux et des molecules de cyclohexane par double resonance electronique-nucleaire, constituent des methodes tres precises pour analyser localement les mouvements presents dans la matrice de cyclohexane. Ce principe et ces techniques constituent la 'methode de la sonde radicalaire'. (auteur)

  19. Le traitement informatisé de ressources électroniques au Service de l'Information Scientifique du CERN

    CERN Document Server

    Pignard, Nathalie; Jerdelet, Jocelyne

    2001-01-01

    Nous présentons une méthode automatique d'importation de données mise en oeuvre au Service de l'Information Scientifique, SIS, du CERN. Ce programme informatique, baptisé Uploader, permet d'importer dans le catalogue de la bibliothèque du CERN des notices bibliographiques et le texte intégral de documents provenant de diverses sources sur Internet. Ces bases de données concernent la littérature grise en physique et dans les disciplines voisines (par exemple DOE, KEK, Math-Doc, TipTop, etc.). Cette politique d'acquisition, qui met en avant le traitement informatisé des ressources électroniques, soulève quelques réflexions sur l'augmentation du nombre de documents collectés et sur l'élargissement des domaines traités. Le souci constant d'enrichir ces données et d'en faciliter l'accès aux utilisateurs, sur un mode hypertextuel, conduit à une évolution des métiers de la gestion documentaire.

  20. Experimental transmission electron microscopy studies and phenomenological model of bismuth-based superconducting compounds; Etudes experimentales par microscopie electronique en transmission et modele phenomenologique des composes supraconducteurs a base de bismuth

    Energy Technology Data Exchange (ETDEWEB)

    Elboussiri, Khalid

    1991-09-26

    The main part of this thesis is devoted to an experimental study by transmission electron microscopy of the different phases of the superconducting bismuth cuprates Bi{sub 2}Sr{sub 2}Ca{sub n-1}Cu{sub n}O{sub 2n+4}. In high resolution electron microscopy, the two types of incommensurate modulation realized in these compounds have been observed. A model of structure has been proposed from which the simulated images obtained are consistent with observations. The medium resolution images correlated with the electron diffraction data have revealed existence of a multi-soliton regime with latent lock in phases of commensurate periods between 4b and 10b. At last, a description of different phases of these compounds as a result of superstructures from a disordered perovskite type structure is proposed (author) [French] Le travail presente dans cette these consiste en une etude experimentale essentiellement par microscopie electronique en transmission des differentes phases supraconductrices presentes dans les composes appartenant a la famille des cuprates de bismuth Bi{sub 2}Sr{sub 2}Ca{sub n-1}Cu{sub n}O{sub 2n+4}. Les obsevations de microscopie electronique a haute resolution ont permis de mettre en evidence les differentes modulations incommensurables realisees dans ces composes. Un modele de structure est propose et a permis d'obtenir des images simulees compatibles avec les observations. D'autre part, les observations de microscopie electronique en moyenne resolution sur ces composes, combinees avec les resultats de diffraction electronique, ont montre l'existence d'un regime multisoliton associe a des phases de Lock-in latentes de parametres compris entre 4b et 10b. Enfin, une description des differentes phases de ces composes en terme de surstructures derivees de structure perovskite desordonnee est exposee. (auteur)

  1. Detectors - Electronics; Detecteurs - Electronique

    Energy Technology Data Exchange (ETDEWEB)

    Bregeault, J.; Gabriel, J.L.; Hierle, G.; Lebotlan, P.; Leconte, A.; Lelandais, J.; Mosrin, P.; Munsch, P.; Saur, H.; Tillier, J. [Lab. de Physique Corpusculaire, Caen Univ., 14 (France)

    1998-04-01

    The reports presents the main results obtained in the fields of radiation detectors and associated electronics. In the domain of X-ray gas detectors for the keV range efforts were undertaken to rise the detector efficiency. Multiple gap parallel plate chambers of different types as well as different types of X {yields} e{sup -} converters were tested to improve the efficiency (values of 2.4% at 60 KeV were reached). In the field of scintillators a study of new crystals has been carried out (among which Lutetium orthosilicate). CdTe diode strips for obtaining X-ray imaging were studied. The complete study of a linear array of 8 CdTe pixels has been performed and certified. The results are encouraging and point to this method as a satisfying solution. Also, a large dimension programmable chamber was used to study the influence of temperature on the inorganic scintillators in an interval from -40 deg. C to +150 deg. C. Temperature effects on other detectors and electronic circuits were also investigated. In the report mentioned is also the work carried out for the realization of the DEMON neutron multidetector. For neutron halo experiments different large area Si detectors associated with solid and gas position detectors were realized. In the frame of a contract with COGEMA a systematic study of Li doped glasses was undertaken aiming at replacing with a neutron probe the {sup 3}He counters presently utilized in pollution monitoring. An industrial prototype has been realised. Other studies were related to integrated analog chains, materials for Cherenkov detectors, scintillation probes for experiments on fundamental processes, gas position sensitive detectors, etc. In the field of associated electronics there are mentioned the works related to the multidetector INDRA, data acquisition, software gamma spectrometry, automatic gas pressure regulation in detectors, etc

  2. Nouvelles techniques de mise en valeur des ressources d'hydrocarbures New Techniques for Valorising Hydrocarbon Resources

    Directory of Open Access Journals (Sweden)

    Boy De la Tour X.

    2006-11-01

    Full Text Available Après avoir montré l'importance des réserves de pétrole non conventionnel et l'enjeu que représente pour l'humanité la mise en exploitation de ces ressources, cette étude examine les axes actuels de recherches et l'état de la technologie pour chacune des sources de nouveau pétrole retenues : mers profondes, récupération assistée, huiles lourdes et sables asphaltiques, schistes bitumineux et conversion du charbon. Il en ressort que si les ressources de nouveau pétrole sont considérables, leur mise en valeur nécessitera des investissements très lourds, et le coût du pétrole ainsi produit restera élevé, comparé au coût actuel du pétrole conventionnel. Compte tenu des délais de mise en oeuvre, des problèmes technologiques restant à résoudre et de la nécessité de réaliser des pilotes semi-industriels très coûteux pour expérimenter les nouvelles techniques, il convient de consentir sans attendre un effort important de recherche technologique, impliquant un accroissement sensible des budgets de R&D, mais aussi des incitations financières appropriées. Cet effort de mise au point de technologies adaptées à ces sources d'hydrocarbures sera favorisé par les nouvelles conditions économiques créées par la rareté relative des réserves d'hydrocarbures classiques, à condition que les Etats, par leur politique, favorisent la production de ressources d'hydrocarbures à coût élevé. A l'heure actuelle, on peut évaluer la production de pétrole difficile à environ 100 Mt, l'essentiel étant réalisé dans le domaine des huiles lourdes et de la récupération assistée ; on estime que la production de nouveau pétrole pourrait représenter 200 à 350 Mt en 1990 et se situer entre 600 et 900 Mt en 2000, soit 5 à 8 % de la production de pétrole en 1990 et 15 à 20 % en 2000. Un tel objectif nécessiterait des investissements de l'ordre de 500 à 750 milliards de dollars 1980. After pointing out the importance of

  3. Fabrication de transistors mono-electroniques en silicium pour le traitement classique et quantique de l'information: une approche nanodamascene

    Science.gov (United States)

    Harvey-Collard, Patrick

    Les transistors mono-electroniques (SETs) sont des dispositifs ayant un grand potentiel d'applications, comme la detection de charge ultra-sensible, la logique a basse consommation de puissance, la memoire ou la metrologie. De plus, la possibilite de pieger un seul electron et de manipuler son etat de spin pourrait permettre des applications en informatique quantique. Le silicium est un materiau interessant pour fabriquer l'ilot d'un SET. Son gap semi-conducteur permet le fonctionnement du dispositif dans le regime a un seul electron ou trou et pourrait permettre d'etendre la plage d'operation du SET en temperature en augmentant l'energie d'addition du diamant central de la valeur du gap. En outre, le silicium beneficie de plus de quarante annees d'expertise en microfabrication et d'une compatibilite avec la technologie metal--oxyde--semi-conducteur complementaire (CMOS). Cependant, la fabrication de ces dispositifs fait face a de serieuses limitations a cause de la taille nanometrique requise pour l'ilot. A ce jour, les procedes de fabrication proposes permettant l'operation a la temperature ambiante sont trop peu reproductibles pour permettre des applications a grande echelle. Dans ce memoire de maitrise, la fabrication de transistors mono-electroniques en silicium (Si-SETs) pour le traitement classique et quantique de l'information est realisee avec un procede nanodamascene. Le polissage chimico-mecanique (CMP) est introduit comme etape clef de la fabrication du transistor, permettant le controle au nanometre pres (nanodamascene) de l'epaisseur du transistor. Cet outil permet la fabrication de dispositifs ayant une geometrie auparavant impossible a realiser et ouvre la porte a l'innovation technologique. De plus, un procede de gravure du silicium par plasma a couplage inductif (ICP) est developpe pour permettre la fabrication de nanostructures de silicium sur une nanotopographie alliant le nano et le 3D. Les Si-SETs fabriques sont caracterises a basse

  4. Acquis et défis de la gestion participative des ressources forestières : Cas du Parc National d’Ifrane

    Directory of Open Access Journals (Sweden)

    Larbi Aziz

    2014-03-01

    Full Text Available Les ressources forestières constituent un capital naturel pour l’approvisionnement des populations locales, en bois, en plantes aromatiques et médicinales et en parcours pour le pâturage. Ces multiples usages ont conduit ces populations à mettre en place une gestion communautaire et très ancienne de ces ressources. Depuis 2002, l’administration des Eaux et Forêts a mis en place une politique forestière basée sur une stratégie de gestion participative. Nous avons étudié les formes de gestion communautaire et par l’administration des ressources forestières dans quatre communes rurales du Parc National d’Ifrane. L’administration organise une mise en défens, fondée sur l’implication et la responsabilisation des populations usagères, organisée en associations sylvo-pastorales ou en coopératives forestières, à travers une incitation financière sous forme de compensation. Ce mécanisme a permis d’obtenir un certain nombre d’acquis : conscientisation des populations vis-à-vis de la mise en défens, investissement des sommes de la compensation dans des projets de développement local, etc. Cependant, ce mécanisme présente certaines fragilités, notamment un risque de non durabilité des mises en défens (du fait que celles-ci ne sont financées que par le budget de l’Etat et un contrôle social plus faible dans les nouvelles associations qui n’ont pas la même légitimité pour prendre des décisions au nom du collectif que les anciennes jmaa.

  5. La Gestion Locale Sécurisée (GELOSE : L’expérience malgache de gestion décentralisée des ressources naturelles

    Directory of Open Access Journals (Sweden)

    Bruno Sarrasin

    2009-09-01

    Full Text Available Marqué par une biodiversité exceptionnelle et une grande pauvreté humaine, la destruction rapide des ressources naturelles à Madagascar place le territoire et son appropriation au centre des enjeux de développement. Dans ce contexte, cet article s’intéresse à l’émergence et à la mise en œuvre d’une politique publique touchant la Gestion LOcale SÉcurisée (GELOSE dont le principal objectif vise à transférer la gestion de ces ressources, de l’État vers les communautés locales, dans le but de les protéger plus efficacement. Cette lecture montre cependant que les objectifs, les ressources et les stratégies des principaux acteurs concernés sont difficilement conciliables et que le système de relation qu’il induit n’est pas nécessairement en phase avec les finalités poursuivies.Marked by exceptional biodiversity and extreme human poverty, Madagascar is experiencing a rapid destruction of its natural resources, placing territory and its appropriation at the heart of development issues. From this perspective, this article will look at the development and implementation of a public policy, the Gestion LOcale SÉcurisée (GELOSE, for the local management of natural renewable resources. This regulation seeks to transfer the management of these resources from the government to local communities in the goal of protecting them more effectively. We will see, however, that the objectives, resources and strategies of the primary actors concerned are difficult to reconcile at best and that the relational system to which the policy gives rise is not necessarily in keeping with the goals being pursued.

  6. Faut-il brûler les dictionnaires ? Ou comment les ressources numériques ont révolutionné les recherches en morphologie

    Directory of Open Access Journals (Sweden)

    Namer Fiammetta

    2012-07-01

    Full Text Available Pour mener leurs études, les morphologues, et, singulièrement parmi eux, ceux qui traitent du lexique construit, sont pris entre deux tensions : utiliser les données issues des dictionnaires, réputées fiables parce que passées au travers du crible de l’institutionnalisation, ou se fonder sur des données authentiques, produites dans des situations écologiques. Bien qu’inspirant encore de la défiance, le Web devient alors la ressource par excellence. Les ressources numérisées telles que les archives de journaux ou les bases de données de textes littéraires constituent un moyen terme entre ces deux pratiques : elles permettent d’effectuer des recherches basées sur l’usage, tout en offrant la garantie d’une certaine tenue linguistique de la part des scripteurs, la plupart du temps identifiables. Dans cette communication, nous nous demanderons si les dictionnaires méritent la confiance que continuent de leur octroyer les morphologues ou, plus exactement, si une morphologie qui puise ses données dans les seuls dictionnaires peut encore avoir cours au 21e siècle. Pour engager cette discussion, nous commencerons par poser la question de l’existence, pour un lexème construit. Nous exposerons ensuite ce que constitue une morphologie basée sur l’usage, puis donnerons un aperçu des types de recherches que permettent de réaliser les ressources non dictionnairiques. La conclusion sera que, si les dictionnaires continuent d'avoir droit de cité dans la panoplie du morphologue, une morphologie uniquement basée sur les données qu'ils contiennent passerait outre de nombreuses recherches, plus fructueuses les unes que les autres.

  7. Procédé de traitement d'une ressource fluide, programme d'ordinateur et module de traitement associés

    OpenAIRE

    Rapaport, Alain; Rousseau, Antoine; Harmand, Jérôme

    2014-01-01

    Pour la bio-remédiation de ressources en eau (bassins, lacs..) qui nécessitent d’être traitées par une unité externe de purification à l’aide de bioprocédés, l’invention consiste à mettre en place un réseau « intelligent » de pompes qui s’adaptent au cours du temps à l’hydrodynamique et à la pollution du milieu. L’objectif est d’optimiser la durée du traitement et/ou la qualité de la remédiation.

  8. Citations des ressources électroniques dans les publications scientifiques : analyse comparée et stratégie des liens

    OpenAIRE

    Chartron , Ghislaine; Caillon , Elisabeth

    2008-01-01

    International audience; Cette communication s'intéresse aux nouvelles dimensions de la citation dans les textes scientifiques dans le contexte numérique. A l'appui d'une étude exploratoire quantitative menée fin 2007 et début 2008 dans le domaine de la biologie moléculaire, de la physique appliquée et de l'économie-gestion, les résultats montrent une faible intégration de ressources Web dans les textes (en dehors des versions en ligne des vecteurs traditionnels), sauf pour la biologie molécul...

  9. The thin layer technique and its application to electron microscopy; La technique des couches minces et son application a la microscopie electronique

    Energy Technology Data Exchange (ETDEWEB)

    Ranc, G. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1957-10-15

    This work deals with the technique of thin layers obtained by evaporation under vacuum, in the thickness range extending from a few monoatomic layers to several hundred angstroms. The great theoretical and practical interest of these layers has, it is well known, given rise to many investigations from Faraday onwards. Within the necessarily restricted limits of this study, we shall approach the problem more particularly from the point of view of: - their production; - their use in electron microscopy. A critical appraisal is made, in the light of present-day knowledge, based on our personal experience and on an extensive bibliography which we have collected on the subject. (author) [French] Le present travail concerne la technique des couches minces obtenues par evaporation sous vide, dans le domaine d'epaisseur qui s'etend de quelques couches monoatomiques a plusieurs centaines d'angstroms. L'interet theorique et pratique considerable de ces couches a suscite, comme on sait, de nombreux travaux depuis Faraday. Dans le cadre necessairement restreint de cette these, nous aborderons plus particulierement le point de vue de: - leur obtention; - leur utilisation en microscopie electronique. Il s'agit d'une mise au point critique, a la lumiere des connaissances actuelles, appuyee sur notre experience personnelle et sur une importante bibliographie, qu'il nous a ete donne de reunir a ce sujet. (auteur)

  10. The thin layer technique and its application to electron microscopy; La technique des couches minces et son application a la microscopie electronique

    Energy Technology Data Exchange (ETDEWEB)

    Ranc, G [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1957-10-15

    This work deals with the technique of thin layers obtained by evaporation under vacuum, in the thickness range extending from a few monoatomic layers to several hundred angstroms. The great theoretical and practical interest of these layers has, it is well known, given rise to many investigations from Faraday onwards. Within the necessarily restricted limits of this study, we shall approach the problem more particularly from the point of view of: - their production; - their use in electron microscopy. A critical appraisal is made, in the light of present-day knowledge, based on our personal experience and on an extensive bibliography which we have collected on the subject. (author) [French] Le present travail concerne la technique des couches minces obtenues par evaporation sous vide, dans le domaine d'epaisseur qui s'etend de quelques couches monoatomiques a plusieurs centaines d'angstroms. L'interet theorique et pratique considerable de ces couches a suscite, comme on sait, de nombreux travaux depuis Faraday. Dans le cadre necessairement restreint de cette these, nous aborderons plus particulierement le point de vue de: - leur obtention; - leur utilisation en microscopie electronique. Il s'agit d'une mise au point critique, a la lumiere des connaissances actuelles, appuyee sur notre experience personnelle et sur une importante bibliographie, qu'il nous a ete donne de reunir a ce sujet. (auteur)

  11. Measurement of the electronic density of ionised media by hyper frequency methods; Mesure de la densite electronique des milieux ionises par des methodes hyperfrequences

    Energy Technology Data Exchange (ETDEWEB)

    Consoli, T [Commissariat a l' Energie Atomique, Saclay (France).Centre d' Etudes Nucleaires

    1960-07-01

    Within the limits of the I.N.S.T.N. courses on plasmas, this analytical study summarizes the articles quoted in the references on hyper-frequency techniques for the measurement of electronic density of an ionised gas. It is neither exhaustive nor complete and further details may be obtained by referring to the works mentioned. The first part, devoted to the theoretical side, concert the propagation of electromagnetic waves ionised media and the excitation of stationary raves in electromagnetic cavities. The second part deals with the measurement techniques themselves. It includes those techniques which hare become classic, and also more recent ones being developed in various laboratories and in the Service of Applied Physics at Saclay. (author) [French] Dans le cadre des cours sur les plasmas a l'l.N.S.T. cette etude d'analyse resume les articles cites en bibliographie sur les techniques hyperfrequences pour la mesure de la densite electronique d'un gas ionise. Elle n'est ni exhaustive, ni complete. Pour plus de details on voudra bien se rapporter aux travaux mentionnes. La premiere partie consacree a des rappels theoriques, concerne la propagation des ondes electromagnetiques dans les milieux ionises et sur l'excitation d'ondes stationnaires dans les cavites electromagnetiques. La seconde se rapporte aux techniques de mesures proprement dites. On a fait figurer dans cette partie des techniques devenues classiques et celles plus recentes en cours d'etudes dans divers laboratoires et au Service de Physique Appliquee a SACLAY. (auteur)

  12. Design and construction of a faraday cup for measuring small electron currents; Etudes et realisation d'une ''coupe de faraday'' pour les mesures de faibles courants electroniques

    Energy Technology Data Exchange (ETDEWEB)

    Veyssiere, A [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1967-07-01

    This paper describes the design of a device for measuring and integrating very small currents generated by the impact of a charged particle beam upon a Faraday cup. Part one considers the detector as such. The main component is a graphite bloc capable of stopping practically all the incident charges. Part two describes the associated electrode apparatus required to measure better than 10{sup -13} ampere with a precision- of 1 per cent: Integration of such weak currents over periods of several hours, in the presence of a strong background current, is also discussed. (author) [French] Ce rapport decrit l'etude et la realisation d'un ensemble permettant de mesurer et d'integrer sur des periodes de plusieurs heures des courants electroniques tres faibles provenant d'un faisceau de particules chargees, Dans la premiere partie du rapport nous etudierons le capteur proprement dit qui se compose essentiellement d'un bloc de graphite dont la forme et les dimensions sont telles, que la majeure partie des charges (positons et negatons de 60 MeV) est captee (1 pour mille reussissent a s'echapper). Dans la deuxieme partie nous decrivons l'appareillage associe au capteur capable de mesurer moins de 10{sup -13} ampere avec une precision de l'ordre du pour cent et d'integrer ce courant sur des periodes de temps variables, compte tenu de l'ambiance 'bruyante' (Accelerateur Lineaire) dans laquelle la mesure s'effectue. (auteur)

  13. Cost efficiency and ressource efficiency in the waste management. Proceedings; Kosten- und Ressourceneffizienz in der Abfallwirtschaft. Tagungsband

    Energy Technology Data Exchange (ETDEWEB)

    Fricke, K. [Arbeitskreis fuer die Nutzbarmachung von Siedlungsabfaellen (ANS) e.V., Braunschweig (Germany)]|[Technische Univ. Braunschweig (Germany). Lehrstuhl fuer Abfall- und Ressourcenwirtschaft; Bergs, C.G. [Bundesministerium fuer Umwelt, Naturschutz und Reaktorsicherheit, Berlin (Germany); Kosak, G. [Arbeitskreis fuer die Nutzbarmachung von Siedlungsabfaellen (ANS) e.V., Braunschweig (Germany)]|[IBK-Kosak GmbH, Neustadt/Weinstrasse (Germany); Wallamnn, R. (eds.) [Arbeitskreis fuer die Nutzbarmachung von Siedlungsabfaellen (ANS) e.V., Braunschweig (Germany)]|[IGW Ingenieurgemeinschaft Witzenhausen Fricke und Turk GmbH (Germany)

    2007-07-01

    Within the scope of the 68th information discussion of ANS e.V., the following lectures were held: (a) Supply of resources from the German waste management (S. Harmening); (b) Ressource management: A contribution to environment, climate and fees (R. Siechau); (c) Climate protection and protection of resources by means of export of technology and know-how (A. Jaron); (d) The future of the markets of secondary raw materials (E. Rehbock, T. Probst); (e) Potentials of increase of the contributions o the waste management to climate protection and protection of resources (G. Dehoust, U. Fritsche); (f) Evaluation of new strategic efforts to disposal of domestic wastes under consideration of resource efficiency and relevance of climate (M. Kranert, G. Hafner); (g) REACh and secondary raw materials (B. Kummer); (h) What is the effect of the regulation of chemicals (REACh) on the recycling economy? (A. Ochs, H. Kleinwege); (i) Motivation and steps of planning according to rekommunalisation (K.-H. Kellermann); (j) Chances and risks of private disposers (P. Kurth); (k) Cost advantages and boundary conditions at intercommunal cooperations of procurement (H. Gassner); (l) From BAB to budgeting - why does a new advertising of service contracts not result in an improvement of the communal efficiency? (W.P. Bauer, K. Ihmels); (m) Benchmarking as an instrument of control in the waste management (K. Gellenbeck); (n) Minimizing financial costs - the funding programs of KW in the waste management (M. von Zedlitz); (o) Innovative models of cooperation, financing and operating models for the establishment of new fermentation plants (M. Zeifang); (p) BEKON dry fermentation for production of biogas from organic waste (P. Lutz); (q) New methods for process control during composting - a component in the enhancement of efficiency of utilization of biological wastes (Frank Scholwin, Gereon Stolle); (r) Enhancement of the output of biogas by means of specific loading materials (Heinrich Josef

  14. Mangler - ressourcer - erfaring

    DEFF Research Database (Denmark)

    Pedersen, Michael Svendsen

    2008-01-01

    Stort frafald og lavt niveau hos etniske minoritetselever i erhvervsuddannelserne er problemer som forsøges løst gennem en lang række pædagogiske udviklingsprojekter. Der udvises både kreativitet og engagement i bestræbelserne på at finde "værktøjer" der kan hjælpe eleverne til at forblive i og g...

  15. Learning in Ressource Mangement

    DEFF Research Database (Denmark)

    Hoffmann, Birgitte; Agger, Annika

    2005-01-01

    This paper explores the roles of NGOs as intermediaries in societal learning processes. The key question is how NGOs facilitate learning in the water sector, and the paper explores the notion of critical friends to grasp their dual position as both partner in the development and critical...... strategies and finally in relation to changes of the water management discourse. Developing the notion ‘critical friend’ the paper discusses how the NGO facilitates learning processes. Traditional approaches to learning are often based on the ‘petrol station pedagogy’ in which knowledge figuratively ‘are...

  16. Study of the nature and of the properties of paramagnetic centers observed by electron spin resonance in conjugated polymers; Etude de la nature des propriete des centres paramagnetiques observes par resonance paramagnetique electronique dans les polymeres conjugues

    Energy Technology Data Exchange (ETDEWEB)

    Nechtschein, M [Commissariat a l' Energie Atomique, Grenoble (France). Centre d' Etudes Nucleaires

    1967-06-15

    Conjugated polymers contain paramagnetic centers. It is established that these centers are free radicals and a model which defines their electronic structure is proposed. The interactions between these centers are studied, notably by dynamic polarisation experiments. Finally it is shown that the centers have catalytic properties. (author) [French] Les polymeres conjugues contiennent des centres paramagnetiques. L'origine radicalaire de ces centres est etablie et un modele precisant leur structure electronique est propose. Les interactions entre ces centres sont etudiees, notamment a l'aide d'experiences de polarisation dynamique. Des proprietes catalytiques sont mises en evidence. (auteur)

  17. Study of the nature and of the properties of paramagnetic centers observed by electron spin resonance in conjugated polymers; Etude de la nature des propriete des centres paramagnetiques observes par resonance paramagnetique electronique dans les polymeres conjugues

    Energy Technology Data Exchange (ETDEWEB)

    Nechtschein, M. [Commissariat a l' Energie Atomique, Grenoble (France). Centre d' Etudes Nucleaires

    1967-06-15

    Conjugated polymers contain paramagnetic centers. It is established that these centers are free radicals and a model which defines their electronic structure is proposed. The interactions between these centers are studied, notably by dynamic polarisation experiments. Finally it is shown that the centers have catalytic properties. (author) [French] Les polymeres conjugues contiennent des centres paramagnetiques. L'origine radicalaire de ces centres est etablie et un modele precisant leur structure electronique est propose. Les interactions entre ces centres sont etudiees, notamment a l'aide d'experiences de polarisation dynamique. Des proprietes catalytiques sont mises en evidence. (auteur)

  18. E. P. R. spectroscopic study of nitroxide mono- and bi-radicals; Etude par spectroscopie de resonance paramagnetique electronique de monoradicaux et de biradicaux nitroxydes

    Energy Technology Data Exchange (ETDEWEB)

    Lemaire, H [Commissariat a l' Energie Atomique, Grenoble, 38 (France). Centre d' Etudes Nucleaires

    1967-07-01

    parfaitement bien definis au point de vue structure chimique. L'etude par resonance paramagnetique electronique de monoradicaux nitroxydes conduit a la determination des axes et des elements du tenseur d'interaction hyperfine electron-noyau d'azote et du tenseur d'anisotropie du facteur de Lande: les resultats sont relies a la structure electronique des radicaux. On interprete qualitativement l'influence du solvant sur les elements des tenseurs, ainsi que les elargissements selectifs des raies hyperfines en milieu visqueux. Dans les biradicaux nitroxydes, la structure hyperfine depend non seulement des interactions magnetiques propres a chaque monomere, mais egalement de la grandeur de l'interaction d'echange separant les etats singulet et triplet du dimere; les biradicaux etudies ici sont les premiers composes organiques pour lesquels l'influence de l'echange sur la structure hyperfine est clairement mise en evidence. La presence de deux electrons non apparies introduit egalement une interaction magnetique dipolaire electron-electron, que l'on peut mettre a profit, dans le cas d'un echange intermediaire, pour determiner le signe de l'echange en etudiant le biradical dans un cristal liquide. Ces composes presentent egalement des elargissements selectifs de transitions hyperfines lorsque la viscosite du solvant croit. La theorie utilisee pour interpreter les largeurs de raie des monoradicaux est etendue au cas des biradicaux; elle rend compte des resultats experimentaux si l'on introduit simultanement les anisotropies des facteurs de Lande et des interactions dipolaires electrons-noyaux et electron-electron, en conduisant a une autre determination du signe de l'echange. (auteur)

  19. Applications of electron spin resonance to some problems of radiation chemistry; Applications de la resonance paramagnetique electronique a quelques problemes de chimie sous rayonnements

    Energy Technology Data Exchange (ETDEWEB)

    Chachaty, C [Commissariat a l' Energie Atomique Saclay (France). Centre d' Etudes Nucleaires

    1968-06-01

    The electron spin resonance (E.S.R.) spectra of gamma irradiated polar organic glasses, at 77 K, shows a single line centered at g {approx} 2, attributed to solvated electrons. The radicals produced on scavenging this species by electron acceptors, such as aromatic hydrocarbons, nitro-compounds and azines have been studied by E.S.R. In most cases, the radicals from these solutes, the spectra of which are observed after elimination by warming of the radicals from the matrices, are produced by protonation of the anions formed by scavenging of electrons at 77 K. Thus, in the case of glassy solutions of nitro-compounds, the radicals R NO{sub 2}H are formed. They are characterized by a{sub N} = 15 G (nitrobenzene) or a{sub N} = 28 G (nitro-alkane). These radicals are also generated by U.V, photolysis at room temperature of solutions of nitro-compounds in alcohols and are shown to be the precursors of nitroxide radicals R - N - R (with N - O) observed simultaneously. Gamma irradiation of solutions of pyridine and of the three diazines, in alcohol glasses at 77 K, produces the radical formed by hydrogen addition to these compounds. The value of the coupling constant of the additional proton (7-10 G) indicates that it is bound to a nitrogen in the sp{sup 2} hydridation state. One has shown, taking pyridine as an example, that the addition to a carbon gives a much greater value of the coupling constant, of the order of 50-60 G. (author) [French] Les spectres de resonance paramagnetique electronique (R.P.E.) obtenus apres irradiation gamma, a 77 K, de verres organiques polaires tels que les alcools, comportent une bande unique centree a g {approx} 2, attribuable aux electrons solvates. On etudie par R.P.E. les radicaux provenant de leur capture par des solutes ayant une affinite electronique, en particulier les hydrocarbures aromatiques, les composes nitres et les azines. En general, les radicaux provenant de ces solutes, dont on observe les spectres apres elimination

  20. La gestion des ressources humaines peut-elle être un facteur de fidélisation de la clientèle du centre E. Leclerc Casteldis ?

    OpenAIRE

    Laurie Ple

    2010-01-01

    Le secteur de la grande distribution est un domaine passionnant par son histoire, son évolution et sa place au cœur de nombreuses mutations de notre société. L'explorer à travers la gestion des ressources humaines est tout de suite paru attirant. Étant donné que la grande distribution évolue dans un contexte de plus en plus compétitif, la fidélisation de la clientèle est devenue un de ses grands enjeux. La grande distribution a développé des outils de fidélisation, mais ils sont largement rep...

  1. Study of the point defects formed in cobalt by electron bombardment; Etude des defauts ponctuels crees par bombardement electronique dans le cobalt

    Energy Technology Data Exchange (ETDEWEB)

    Sulpice, G [Commissariat a l' Energie Atomique, 38 - Grenoble (France). Centre d' Etudes Nucleaires

    1968-12-01

    A study of the point defects formed in cobalt by electron bombardment is presented. The results are compared with those previously obtained for two other ferromagnetic metals of different structure, iron and nickel. In the first part we give a review of the literature concerning the creation of point defects, their contribution to resistivity and their annihilation mode in the three structure types. We then describe the experimental techniques adapted, in particular the study of the resistivity increase during a linear temperature rise. Our investigations concern the following, essential points : the observation of the successive annihilation stages of the point defects formed in pure cobalt, a study of the variations with respect to the doses and energy of the incident particles, and the determination of the annealing kinetics and the corresponding activation energies. The results are finally compared with the various models of point defect annihilation proposed for other metals: none of these interpretations is in perfect agreement with our results. In the case of cobalt we are thus led to modify the model proposed by our laboratory for iron an nickel. The difference between these three metals is explained by the anisotropic character of the cobalt matrix. (author) [French] Nous presentons une etude des defauts ponctuels crees par bombardement electronique dans le cobalt et comparons nos resultats a ceux obtenus precedemment dans deux autres metaux ferromagnetiques de structure differente, le fer et le nickel. Dans une premiere partie nous faisons une mise au point bibliographique comparee sur la creation des defauts, leur contribution a la resistivite et leur mode d'annihilation dans les trois types de structure. Nous decrivons ensuite les techniques experimentales mises au point, en particulier l'etude du revenu de la resistivite au cours d'une montee lineaire de temperature. Au cours de ce travail, nous avons mis en evidence les stades successifs d

  2. Contribution to the study of point defects formed in nickel by electron bombardment; Contribution a l'etude des defauts ponctuels crees par bombardement electronique dans le nickel

    Energy Technology Data Exchange (ETDEWEB)

    Oddou, J L [Commissariat a l' Energie Atomique, 38 - Grenoble (France). Centre d' Etudes Nucleaires

    1968-12-01

    After a short account of the experimental techniques employed in our studies, the experimental results obtained on pure nickel samples are exposed. The apparition of the successive annihilation stages of point defects created by electron bombardment is established by isochronal heat treatments: the annihilation kinetics and the corresponding activation energies are determined. The effect of the incident particle doses is also studied. The experimental results are then compared with R.A. Johnson's theoretical calculations of the stability and the migration of point defects in nickel, and taking into account the results obtained by Peretto in magnetic after effect measurements. This leads us to a model in good agreement with calculations and experiment for the first stages. In a second chapter the behaviour of nickel doped by certain impurities is studied. First, the results concerning the rate of increase of resistivity (function of sample purity) is investigated. Two possible explanations of the observed phenomenon are proposed: either a deviation with respect to Mathiessen's law, or an increase of the number of defects formed in the presence of impurity atoms. Finally, a study of the resistivity recovery of the doped samples permits us to suggest an order of magnitude for the binding energy interstitial/impurity atom in the nickel matrix. (author) [French] Apres avoir brievement rappele les techniques experimentales que nous avons utilisees pour cette etude, nous exposons les resultats experimentaux obtenus sur des echantillons de nickel pur. Les stades successifs d'annihilation des defauts ponctuels crees par bombardement electronique sont mis en evidence par traitements thermiques isochrones; les cinetiques de disparition, et les energies d'activation correspondantes sont determinees. Nous etudions egalement l'effet de la dose des particules incidentes. Les resultats experimentaux sont ensuite compares avec les calculs theoriques de R.A JOHNSON sur la stabilite

  3. Compilation of the calculation elements of the electronic equipments reliability; Recueil des elements de calcul de la fiabilite des equipements electroniques

    Energy Technology Data Exchange (ETDEWEB)

    Lefevre, R.; D' Harcourt, A.; Dupuy, G. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1968-07-01

    The aim of this work is to allow the practical execution of the estimated calculation of the electronic devices reliability and to standardize the source and the approach of the calculations while giving a systematic character to their execution mode. The systematic character of the calculations allows a comparison of the reliability of different materials and a rapid control of the calculations validity; at last, it brings out the use conditions of all the components of a set. A reliability calculation made according to the method described here reveals: -components badly used -the relative influence on the reliability of the set, of a component or a components group taking into account of the number, of the characteristics and of the use of these ones. At last, the results of the calculation allows to organize the exploitation (availability) and the maintenance (staff, stock of components) of the materials. The failure rates given in this book are only relating to the components service-life and do not correspond to precocious failures. (authors) [French] L'objet du present recueil est d'une part de permettre l'execution pratique du calcul previsionnel de la fiabilite des equipements electroniques et d'autre part d'uniformiser l'origine et la presentation de calculs en donnant un caractere systematique a leur mode d'execution. Le caractere systematique des calculs permet une comparaison de la fiabilite de differents materiels et un controle rapide de la validite des calculs; enfin il met en relief les conditions d'utilisation de tous les composants d'un ensemble. Un calcul de fiabilite realise selon la methode preconise par ce document permet la mise en evidence: -des composants mal utilises -de l'influence relative sur la fiabilite de l'ensemble, d'un composant ou d'un groupe de composants compte tenu du nombre, des caracteristiques et de l'utilisation de ceux-ci. Enfin, les resultats du

  4. Evaluation by electronic paramagnetic resonance of the number of free radicals produced in irradiated rat bone; Evaluation par resonance paramagnetique electronique du nombre de radicaux libres produits dans l'os de rat irradie

    Energy Technology Data Exchange (ETDEWEB)

    Marble, G; Valderas, R [Commissariat a l' Energie Atomique, Fontenay-aux-Roses (France). Centre d' Etudes Nucleaires

    1966-07-01

    The number of long half-life free radicals created by gamma irradiation in the bones of the rat has been determined from the electrons paramagnetic resonance spectrum. This number decreases slowly with time (calculated half life: 24 days). It is proportional to the dose of gamma radiation given to the rat. The method could find interesting applications in the field of biological dosimetry. (authors) [French] Le nombre de radicaux libres a vie longue crees par irradiation gamma dans l'os de rat a ete determine a partir du spectre de resonance paramagnetique electronique. Ce nombre decroit lentement avec le temps (demi-vie calculee {approx_equal} 24 jours). IL est proportionnel a la dose de rayonnement gamma delivree au rat. La methode pourra trouver en dosimetrie biologique des applications interessantes. (auteurs)

  5. New measurements in plutonium L X ray emission spectrum using an electron probe micro-analyser; Nouvelles mesures dans le spectre d'emission L du plutonium au moyen d'un micro analyseur a sonde electronique

    Energy Technology Data Exchange (ETDEWEB)

    Bobin, J L; Despres, J [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1966-07-01

    Further studies by means of an electron-probe micro-analyser, allowed report CEA-R--1798 authors to set up a larger plutonium X ray spectrum table. Measurements of plutonium L{sub II} and L{sub III} levels excitation potentials have also been achieved. Some remarks about apparatus performance data (such as spectrograph sensibility, resolving power and accuracy) will be found in the appendix. (authors) [French] Poursuivant les etudes exposees dans le rapport CEA-R--1798, les auteurs ont pu dresser un tableau plus etendu du spectre L du plutonium, au moyen du micro-analyseur a sonde electronique. Ils ont egalement effectue des mesures de potentiel d'excitation des niveaux L{sub II} et L{sub III} du plutonium. On trouvera en annexe quelques notes sur les constantes d'appareillage (sensibilite, pouvoir de resolution et precision des spectrographes). (auteurs)

  6. Evaluation by electronic paramagnetic resonance of the number of free radicals produced in irradiated rat bone; Evaluation par resonance paramagnetique electronique du nombre de radicaux libres produits dans l'os de rat irradie

    Energy Technology Data Exchange (ETDEWEB)

    Marble, G.; Valderas, R. [Commissariat a l' Energie Atomique, Fontenay-aux-Roses (France). Centre d' Etudes Nucleaires

    1966-07-01

    The number of long half-life free radicals created by gamma irradiation in the bones of the rat has been determined from the electrons paramagnetic resonance spectrum. This number decreases slowly with time (calculated half life: 24 days). It is proportional to the dose of gamma radiation given to the rat. The method could find interesting applications in the field of biological dosimetry. (authors) [French] Le nombre de radicaux libres a vie longue crees par irradiation gamma dans l'os de rat a ete determine a partir du spectre de resonance paramagnetique electronique. Ce nombre decroit lentement avec le temps (demi-vie calculee {approx_equal} 24 jours). IL est proportionnel a la dose de rayonnement gamma delivree au rat. La methode pourra trouver en dosimetrie biologique des applications interessantes. (auteurs)

  7. Study of secondary electronic emission in some piezo-electric materials: application to ultrasonic visualization; Etude de l'emission electronique secondaire de quelques materiaux piezoelectriques: application a la visualisation ultrasonore

    Energy Technology Data Exchange (ETDEWEB)

    Marini, J [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1969-07-01

    Methods allowing the visualization of acoustic images appear at the moment to be of great interest in the field of non-destructive testing as well as in that of underwater detection. In order to carry out certain calculations on the operation of an ultrasonic camera, it has been necessary to study the secondary electron emission of some piezoelectric materials liable to be incorporated into the equipment. The secondary electron emission of insulators is a rather complex phenomenon; in order to find a rational explanation for the observations made, a theory has been developed for the energy spectrum of the emitted electrons. The experimental results of this work have then been used to build an ultrasonic visualization installation. Some examples of acoustic images which have been visualized are also presented. (author) [French] Les methodes qui permettent de visualiser des images acoustiques trouvent a l'heure actuelle un grand interet dans le domaine du controle non destructif comme dans celui de la detection sous-marine. De maniere a effectuer certains calculs sur le fonctionnement d'une camera ultrasons, il a ete necessaire d'etudier l'emission electronique secondaire de quelques materiaux piezoelectriques susceptibles d'etre utilises dans sa construction. L'emission electronique secondaire des isolants est un phenomene assez complexe et de maniere a trouver des explications coherentes aux observations effectuees, une theorie du spectre energetique des electrons emis a ete elaboree. Une installation de visualisation ultrasonore a alors ete realisee a partir des donnees experimentales de cette etude. Quelques exemples d'images acoustiques visualisees par cette methode sont egalement presentees. (auteur)

  8. Study of secondary electronic emission in some piezo-electric materials: application to ultrasonic visualization; Etude de l'emission electronique secondaire de quelques materiaux piezoelectriques: application a la visualisation ultrasonore

    Energy Technology Data Exchange (ETDEWEB)

    Marini, J. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1969-07-01

    Methods allowing the visualization of acoustic images appear at the moment to be of great interest in the field of non-destructive testing as well as in that of underwater detection. In order to carry out certain calculations on the operation of an ultrasonic camera, it has been necessary to study the secondary electron emission of some piezoelectric materials liable to be incorporated into the equipment. The secondary electron emission of insulators is a rather complex phenomenon; in order to find a rational explanation for the observations made, a theory has been developed for the energy spectrum of the emitted electrons. The experimental results of this work have then been used to build an ultrasonic visualization installation. Some examples of acoustic images which have been visualized are also presented. (author) [French] Les methodes qui permettent de visualiser des images acoustiques trouvent a l'heure actuelle un grand interet dans le domaine du controle non destructif comme dans celui de la detection sous-marine. De maniere a effectuer certains calculs sur le fonctionnement d'une camera ultrasons, il a ete necessaire d'etudier l'emission electronique secondaire de quelques materiaux piezoelectriques susceptibles d'etre utilises dans sa construction. L'emission electronique secondaire des isolants est un phenomene assez complexe et de maniere a trouver des explications coherentes aux observations effectuees, une theorie du spectre energetique des electrons emis a ete elaboree. Une installation de visualisation ultrasonore a alors ete realisee a partir des donnees experimentales de cette etude. Quelques exemples d'images acoustiques visualisees par cette methode sont egalement presentees. (auteur)

  9. Énergie et bois dans le territoire alpin : stratégies autour d'une ressource incertaine

    Directory of Open Access Journals (Sweden)

    Hélène Avocat*

    2012-02-01

    Full Text Available Depuis dix ans, le bois-énergie se développe dans les territoires alpins, sous l’impulsion de politiques volontaristes. Face à l'épuisement prochain des produits connexes de scierie, déjà largement utilisés dans la papeterie, la panneauterie et la granulation, la plaquette forestière est amenée à se développer pour des usages industriels ou locaux. Il s’agit d’une opportunité pour les territoires et les forêts alpines, dont la vulnérabilité doit cependant être prise en compte dans la délicate conciliation d'objectifs économiques et environnementaux. L’étude des différentes politiques et dispositifs montre des approches très différentes.  Cela peut générer des tensions sur la ressource et donner lieux à des comportements contradictoires avec le développement d’une énergie dite verte : allongements des distances de transports et donc des émissions de polluants, dégradation de l’environnement et de la multifonctionnalité des forêts, etc.

  10. De la connaissance des milieux marins à la gestion raisonnée des ressources From the knowledge of marine environments to the management of marine resources

    Directory of Open Access Journals (Sweden)

    Dominique Augier

    2011-01-01

    Full Text Available Dans le cadre de cet article introductif au dossier thématique sur les ressources marines, les auteurs rappellent les enjeux liés aux usages et types de consommation, à leurs modalités de protection et systèmes de gouvernance. Ils rappellent leur importance environnementale, sociale mais aussi économique pour bon nombre de pays et de communautés côtières. Ils mettent l’accent sur les actions déjà mises en œuvre et sur la nécessité d’approfondir les connaissances dans ce domaine.In this introductory article of the issue paper on marine resources, the authors review the issues with usage and consumption patterns, in terms of protection and governance systems. They stress their environmental significance, social but also economic for many country and coastal communities. They focus on the actions already implemented and the need to deepen knowledge in this field.

  11. Doelgroepsegmentatie in de primaire preventie van cardiovasculaire ziekten

    NARCIS (Netherlands)

    Kok, F.J.

    1982-01-01

    Profiles of target groups (target group segmentation) in the primary prevention of cardiovascular disease (CVD), can lead to an effective target group-directed approach in health education. Objectives in this thesis are: 1) To identify demographic and socioeconomic characteristics of such target

  12. L'emploi de normes et standards efficaces dans l'organisation, la structuration et la diffusion de ressources pédagogiques : les exemples français

    OpenAIRE

    Delmotte , Stéphanie

    2008-01-01

    International audience; Il s'agit actuellement de mettre en place, en Algérie, des conditions optimales pour la production de ressources numériques de qualité pour la diffusion du savoir en ligne, dans un domaine particulier : l'enseignement du berbère dans le cadre d'une revalorisation de cette langue et de sa culture. La langue nationale tamazight, son enseignement et sa normalisation/standardisation constituent un champ d'intérêt et de recherche scientifique à part entière. Ces conditions ...

  13. Gestion alternative des conflits liés à la gestion des ressources forestières dans le cadre de la gestion des terroirs: Rapport de l'atelier national de Sénégal

    OpenAIRE

    Agne, A.; Sylla, C.I.; Ndione, P.D.; Mathieu, H.

    2007-01-01

    Metadata only record Du 17 au 19 Mai 1995, s'est tenu au Centre Foret à Thiès, l'atelier national sur la Gestion Alternative des Conflits liés aux ressources forestières dans le cadre de la gestion des terroirs. Cet atelier qui a réuni une trentaine de participants issus de divers milieux de la recherche, du développement, de la justice, des ONG, de la pressure ainsi que des représentants de bailleurs de fonds (cf. liste des participants), avait entre autre but, la validation et l'enrichis...

  14. Saddam Hussein et la débâcle triomphante. Les ressources insoupçonnées de Umm al-Ma‘ârik

    Directory of Open Access Journals (Sweden)

    Peter Harling

    2007-07-01

    Full Text Available Les performances du régime irakien tout au long de la crise de 1991 ont suscité deux types de lectures opposées. Pour le sens commun, il s’agissait d’une défaite incontestable. Pourtant, Saddam Hussein, de son côté, l’a qualifiée de « Mère des Batailles » (Umm al-Ma‘ârik et de triomphe absolu. Une telle exagération est plus que le simple produit de l’imagination d’un despote. Il le pensait en effet si bien qu’il a, en 2003, élaboré sa stratégie de défense sur le modèle de 1991. Plus significativement, la réponse du régime aux défis qu’il avait lui-même fabriqués en envahissant le Koweit suggère que la crise de 1991 était elle-même la voie de sortie d’une crise plus structurelle à laquelle Saddam Hussein aurait eu toutes les chances de succomber. Cet article explore plusieurs aspects méconnus de ce moment historique. Premièrement, il relie les évènements de 1991 à la banqueroute économique, institutionnelle et symbolique du régime. Deuxièmement, il attire l’attention sur sa réponse complexe à la situation. Troisièmement, il analyse en détail la métamorphose du régime grâce aux ressources offertes par la crise, qui l’ont incité à perpétuer un « régime de crise », devenu la condition paradoxale de la stabilité du régime.

  15. Geophysical Well Logs Applied to Geothermal Resource Evaluation Application des diagraphies à l'évaluation des ressources géothermiques

    Directory of Open Access Journals (Sweden)

    Fertl W. H.

    2006-11-01

    Full Text Available Well logging in the petroleum industry has been developed over five decades into a mature industry, whereas geothermal well logging is a relatively new enterprise. Fundamental differences also occur in the geologic environments and key objectives of both logging applications. Geothermal reservoirs are frequently in fractured igneous and metamorphic rocks, which contain hot water or stem at temperature exceeding 150°C. The discussion focuses on present day logging technology, geologic and reservoir engineering objectives, and qualitive and quantitative formation interpretation techniques for geothermal resource evaluation. Specific field case studies illustrate the interpretive state-of-the-art, including examples from the Geysers dry steam field in the Imperial Valley of California, hot water fields in California, Nevada, and Idaho, and the LASL Hot Dry Rock test project in the Valles Caldera of New Mexico. Les diagraphies dans les forages pétroliers ont atteint leur maturité, alors que le contrôle diagraphique des sondages géothermiques est une entreprise relativement nouvelle. Des différences fondamentales apparaissent aussi dans les environnements géologiques et dans les objectifs clés des deux types d'applications des diagraphies. Les réservoirs géothermiques se situent souvent dans les roches ignées ou métamorphiques fracturées qui contiennent de l'eau chaude ou de la vapeur à des températures dépassant 150 °C. L'exposé sera concentré sur les techniques actuelles d'enregistrements, les objectifs géologiques et liés à l'exploitation des réserves et sur les techniques qualitatives et quantitatives d'interprétation des formations pour l'évaluation des ressources géothermiques. Quelques cas particuliers illustrent l'état actuel des techniques d'interprétation avec des exemples pris dans le champ de vapeur sèche des geysers dans Imperial Valley de Californie, des champs d'eau chaude en Californie, Nevada et Idaho et

  16. Conditions of competition between the production of water by desalination and natural resources; Les conditions de concurrence entre la production d'eau par dessalement et les ressources naturelles

    Energy Technology Data Exchange (ETDEWEB)

    Gaussens, J [Commissariat a l' Energie Atomique, Fontenay-aux-Roses (France). Centre d' Etudes Nucleaires

    1969-07-01

    A close examination of the local supply and demand for fresh water is involved when considering a sea water desalination plant in a given region. This examination makes it possible in most cases to undertake a thorough study of the natural resources, resulting in the use of desalination being rejected. After confirming this fact by precise examples, the authors consider that the preliminary study should be extended, taking into account the complementary character of natural resources and desalination systems: contribution to peak demand, contribution to base demand. This analysis results in a classification of the main user regions according to certain economic criteria defining their suitability for the use of desalination processes. (author) [French] Envisager une installation d'eau de mer dans une region donnee, entraine un examen attentif de l'offre et de la demande locale en eau douce. Cet examen permet de conduire dans la plupart des cas a une etude approfondie des ressources naturelles qui aboutit a ecarter le recours au dessalement. Apres avoir constate ce fait, par des exemples precis, les auteurs estiment que l'on doit pousser plus loin l'etude preliminaire en tenant compte de la complementarite entre les ressources naturelles et les systemes de dessalement: contribution a la demande de pointe, contribution a la demande de base. Cette analyse conduit a classer les regions utilisatrices essentielles selon certains criteres economiques definissant leur aptitude a l'utilisation des procedes de dessalement. (auteur)

  17. Conditions of competition between the production of water by desalination and natural resources; Les conditions de concurrence entre la production d'eau par dessalement et les ressources naturelles

    Energy Technology Data Exchange (ETDEWEB)

    Gaussens, J. [Commissariat a l' Energie Atomique, Fontenay-aux-Roses (France). Centre d' Etudes Nucleaires

    1969-07-01

    A close examination of the local supply and demand for fresh water is involved when considering a sea water desalination plant in a given region. This examination makes it possible in most cases to undertake a thorough study of the natural resources, resulting in the use of desalination being rejected. After confirming this fact by precise examples, the authors consider that the preliminary study should be extended, taking into account the complementary character of natural resources and desalination systems: contribution to peak demand, contribution to base demand. This analysis results in a classification of the main user regions according to certain economic criteria defining their suitability for the use of desalination processes. (author) [French] Envisager une installation d'eau de mer dans une region donnee, entraine un examen attentif de l'offre et de la demande locale en eau douce. Cet examen permet de conduire dans la plupart des cas a une etude approfondie des ressources naturelles qui aboutit a ecarter le recours au dessalement. Apres avoir constate ce fait, par des exemples precis, les auteurs estiment que l'on doit pousser plus loin l'etude preliminaire en tenant compte de la complementarite entre les ressources naturelles et les systemes de dessalement: contribution a la demande de pointe, contribution a la demande de base. Cette analyse conduit a classer les regions utilisatrices essentielles selon certains criteres economiques definissant leur aptitude a l'utilisation des procedes de dessalement. (auteur)

  18. Study by electron spin resonance of the free radicals created under irradiation in glycine; Etude par la technique de resonance paramagnetique electronique des radicaux crees sous irradiation dans la glycine

    Energy Technology Data Exchange (ETDEWEB)

    Thomet, P; Rassat, A; Servoz-Gavin, P; Choudens, H de [Commissariat a l' Energie Atomique, Grenoble (France). Centre d' Etudes Nucleaires

    1967-07-01

    The free radicals created by different radiations in glycine are measured by electron spin resonance and their number is evaluated in function of the absorbed dose. This number decreases when the LET of the radiations increases ; in other words,high LET radiations gives less radiochemical effects; in contrary with the fact that high LET radiations creates more damage in biological materials. The decreasing with time of the number of free radicals and the speed of this decrease is a function of temperature; by the study of the kinetics of this decrease, an attempt has been made to prove the presence of three radicals. (authors) [French] Les radicaux crees par divers rayonnements dans la glycine sont detectes par resonance paramagnetique electronique et leur nombre est evalue en fonction de la dose. Ce nombre varie dans le sens inverse du T.E.L moyen, c'est-a-dire que les rayonnements de T.E.L eleves donnent des effets radiochimiques plus petits alors que les effets radiobiologiques sont importants avec des T.E.L eleves. La decroissance dans le temps du nombre de radicaux est observee et la vitesse de diminution des radicaux est liee a la temperature. Etudiant la cinetique de recombinaison, on peut faire l'hypothese de l'existence de 3 radicaux. (auteurs)

  19. Ressourcer i teori og praksis

    DEFF Research Database (Denmark)

    Ressourceorientering som udgangspunkt for pædagogisk praksis. I bogen møder læseren en række metoder og konkrete tilgange, der på forskellig vis tager udgangspunkt i et ressourcesyn som princip og afsæt for praksis. Ud fra forskellige teoretiske tilgange giver bogen en række bud på, hvordan man s...

  20. La cogestion des Ressources naturelles

    International Development Research Centre (IDRC) Digital Library (Canada)

    L'eau, le sol, les nutriments, la lumière du soleil — ce sont des choses de la vie. .... habitent encore ces régions, soit de 9 % à 14 % de la population mondiale. ...... La guerre civile a fait vivre au Cambodge des années de chaos, d'anarchie et ...... et les allégeances politiques sont des facteurs qu'il est impossible d'ignorer.

  1. Electronic Modification of the Scintigram and its Limitations; Modification Electronique des Scintigrammes: Limitations; Ehlektronnoe usovershenstvovanie stsintigrammy i ego ogranicheniya; Modificacion Electronica de los Centelleogramas: Sus Limitaciones

    Energy Technology Data Exchange (ETDEWEB)

    Conrad, B.; Horst, W. [University Clinic for Radiotherapy and Nuclear Medicine Cantonal Hospital, Zurich (Switzerland)

    1964-10-15

    traitent des problemes ci-apres: 'dimension' optimum de l'element d'information primaire, en fonction du pouvoir de resolution du detectuer; forme optimum de la fonction de conversion suivant l 'objet de l'examen scintigraphique; circuits electroniques permettant de realiser ces fonctions. En particulier, les auteurs decrivent en detail un appareil qui assure une presentation lineaire optimum grace a une fonction de conversion non lineaire appropriee. Ainsi, la gamine des taux de comptage nets, allant du bruit de fond au taux de comptage maximum, se trouve representee dans le scintigramme par toutes les nuances de noircissement, d'une maniere qui reduit a un minimum l'alteration des donnees. On peut aussi choisir d'autres genres de presentation, par exemple differentes caracteristiques quasi-logarithmiques. Le probleme de l'accentuation du contraste lorsque les nuances sont tres faibles, par exemple dans l'exploration des tumeurs du cerveau, sera traite de maniere detaillee. Il est a noter que les principes exposes peuvent s'appliquer non seulement aux detecteurs mobiles utilises en scintigraphie, mais aussi aux detecteurs stationnaires de tous genres. (author) [Spanish] Los autores estudian los principios basicos del aumento del contraste. Al realizar y utilizar los sistemas de conversion deberian observarse cienas leyes fundamentales a fin de permitir la visualizacion del maximo de informaciones. Para determinar esas leyes se han utilizado Los siguientes parametros y funciones, que caracterizan, en general, todos los sistemas de conversion: 1. El elemento fundamental de informacion primaria, definido por los intervalos de tiempo, el numero predeterminado de impulsos, etc . 2. La funcion de conversion de las informaciones, que permite representar el elemento fundamental en el centelleograma (e l grado de ennegrecimiento de un punto luminoso, por ejemplo). A menudo esta funcion se considera como la caracteristica esencial del sistema de conversion, pero esto solo es cierto

  2. Aires protégées, gestion participative des ressources environnementales et développement touristique durable et viable dans les régions ultra-périphériques

    Directory of Open Access Journals (Sweden)

    Jean-Marie Breton

    2009-09-01

    Full Text Available Le tourisme est souvent présenté comme l’un des instruments d’un développement durable, même s’il connaît une expansion difficilement maîtrisable, au détriment du patrimoine environnemental, insulaire et littoral en particulier, comme dans les DOM-TOM.Le tourisme a des impacts, culturels et sociaux notamment, sur l’environnement. Les ressources du patrimoine alimentent de leur côté la demande et l’offre touristiques. Un tourisme assis sur une gestion ad hoc des ressources du patrimoine constitue un facteur puissant de durabilité du développement local. La soumission de l’activité touristique aux exigences de protection, de conservation et de gestion reproductible de la biodiversité et du patrimoine naturel, dans les aires protégées de la Caraïbe française en particulier, génère des approches, des stratégies et des comportements nouveaux. La démarche écotouristique appelle une gestion participative et intégrée des ressources et des espaces, et constitue un défi pour les opérateurs du tourisme comme pour les acteurs de l’environnement, et une opportunité de "réappropriation" de leur milieu de vie par les populations locales. Il faut alors en clarifier le concept et les implications ; puis en analyser les objectifs et les enjeux dans une perspective de développement durable.Tourism often appears as one a tool for a sustainable development, even if it is not easy to control, in the détriment of island and costal environment heritage, as in French overseas regions. Besides the cultural and social impacts of tourism upon environment, the heritage resources nuture the touristic request and offer. If based on an appropriate management of those resources, it may be a strong incentive for local sustainable development. The respect of protection, conservation and sustainable management of biodiversity and natural resources by tourism, especially in the overseas regions of French West Indies, produces new

  3. A study of point defects created by electron irradiation of dilute iron-carbon alloys; Etude des defauts crees par irradiation electronique dans les alliages de fer carbone dilues

    Energy Technology Data Exchange (ETDEWEB)

    Leveque, J L [Commissariat a l' Energie Atomique, Grenoble (France). Centre d' Etudes Nucleaires

    1969-10-01

    Resistivity and magnetic after effect (m.a.e.) measurements are used to study the influence of carbon atoms on the annealing process of point defects created by electron irradiation (3 MeV) at low temperature (20 deg. K). The presence of the carbon atoms has a strong influence on the recovery sub-stage I{sub E} and stage III. For the former, the carbon impurity traps the freely migrating iron interstitial. For the latter the effect is interpreted as being due to formation during annealing, of a carbon vacancy pair. A pronounced m.a.e. band is attributed to the reorientation of this carbon vacancy complex. All these results are coherent with the interpretation of a low temperature migrating free interstitial. (author) [French] L'influence des atomes de carbone sur le recuit des defauts ponctuels crees par irradiation electronique (3 MeV) a basse temperature (20 deg. K) dans le fer est mise en evidence par des mesures de resistivite electrique, et de trainage magnetique. Cette influence se manifeste principalement au cours du sous stade I{sub E} et du stade III de resistivite. Au sous stade I{sub E} les atomes de carbone piegeraient les interstitiels libres de fer au cours de leur migration. Le stade III est interprete comme etant du a la recombinaison du carbone dans les lacunes. Une importante bande de tramage magnetique etant attribuee a la reorientation de ce complexe. Ces resultats sont coherents avec l'interpretation faisant migrer a basse temperature l'interstitiel libre. (auteur)

  4. Study of the machining of uranium carbide rods obtained by continuous casting under electronic bombardment; Etude de l'usinage de barreaux de carbure d'uranium obtenus par coulee continue sous bombardement electronique

    Energy Technology Data Exchange (ETDEWEB)

    Rousset, P; Accary, A [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1965-07-01

    The authors consider the various methods of machining uranium mono-carbide and compare them critically in the case of their application to uranium carbide obtained by fusion under an electronic bombardment and continuous casting. This study leads them to propose two mechanical machining methods: cylindrical rectification and center-less rectification, preceded by a preliminary roughing out of a cylinder, the latter appearing more suitable. A study of the machining yields as a function of the diameter of the rough bars and of the diameter of the finished rods has shown that an optimum value of the rough bar diameter exists for each value of the finished rod diameter. It is found that the yield increases as the diameter itself increases, this yield rising from 45 per cent to around 70 per cent as the diameter of the rough bars increases from 25-26 mm to 37-38 mm. (authors) [French] Les auteurs envisagent les differentes methodes d'usinage du monocarbure d'uranium et se livrent a une etude critique de celles-ci, dans le cas de leur application a l'usinage de barreaux de carbure d'uranium obtenus par fusion sous bombardement electronique et coulee continue. Cette etude les conduit a proposer deux methodes d'usinage mecanique: la rectification cylindrique et la rectification 'centerless', precedee d'un ebauchage par carottage, la seconde paraissant la plus appropriee. L'etude des rendements d'usinage en fonction du diametre des barreaux bruts et du diametre des barreaux finis, a mis en evidence une valeur optimale du diametre des barreaux bruts pour chaque valeur du diametre des barreaux usines. Elle a montre que le rendement croit lorsque le diametre croit lui-meme, ce rendement passant d'environ 45 pour cent a environ 70 pour cent, lorsque le diametre des barreaux bruts passe de 25-26 mm a 37-38 mm.

  5. Study of certain random variations in the measurement of low level radioactivities by means of electric circuits (1963); Etude, au moyen de circuits electroniques, de certaines fluctuations aleatoires dans les mesures de radioactivite a bas niveau (1963)

    Energy Technology Data Exchange (ETDEWEB)

    Moghimi, D [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1963-03-15

    The aim of this work is to find a control method which ensures that there is really a statistical distribution of pulses during the measurement of very low activities. The use of a method based on the distribution of time intervals is examined first, as well as the graphical representation to which it leads. The second method is a study of the distribution of the number of pulses in a given time interval. It makes it possible to use two tests for verifying Gauss's law: Henry's graphical test and the {chi}{sup 2} mathematical test. The electronic devices necessary for these tests have been built; they have made it possible to study the fluctuations in on installation for measuring the natural activity of carbon. (author) [French] Le but de ce travail est de rechercher des methodes de controle qui permettent de s'assurer qu'au cours de mesures de tres faibles activites, on a bien une distribution statistique des impulsions. L'utilisation d'une premiere methode basee sur la distribution des intervalles de temps est d'abord examinee, ainsi que la representation graphique a laquelle elle conduit. La deuxieme methode est une etude de la repartition du nombre d'impulsions pendant un temps determine. Elle permet l'utilisation de 2 tests de verification de la loi de Gauss: le test graphique de Henry et le test mathematique de {chi}{sup 2}. Les dispositifs electroniques necessaires pour l'utilisation de ces tests ont ete realises.; ils ont ensuite permis l'etude des fluctuations dans une installation de mesure d'activite naturelle du carbone. (auteur)

  6. La lutte internationale contre le réchauffement climatique comme étant une source de dégradation des ressources marines The international fight against global warming as a source of degradation of marine resources

    Directory of Open Access Journals (Sweden)

    Syrine Ismaili

    2012-04-01

    Full Text Available Les ressources marines constituent une richesse économique d'une grande importance pour un grand nombre de pays de la planète. Du fait de l'action de l'homme, ces ressources subissent une fragilisation et une raréfaction dues entre autres à la pollution, à la surpêche, à l'urbanisation intensive...S'ajoute à cette liste, depuis quelques années, le réchauffement de la planète qui affecte d'une manière sensible la diversité biologique marine. Pourtant les réponses internationales face à cette dégradation, au delà du fait qu'elles soient timides, sont rares. Il faudra dès lors se rabattre sur les solutions de lutte globale contre le réchauffement de la planète entreprise par la communauté internationale afin de contrer cette dégradation.Marine resources are a wealth of great economic importance for many countries in the world. Due to the action of man, these resources undergo embrittlement and rarification among others to pollution, overfishing, urbanization, intensive ... Added to this list in recent years, the global warming that affects a significantly marine biodiversity. Yet the international response to this degradation, beyond the fact that they are shy, is rare. It will therefore fall back on solutions to the global fight against global warming taken by the international community to counter this degradation.

  7. Electron density and temperature study of plasmas using a millimeter-wave Fabry-Perot interferometer; Etude de la densite electronique et de la temperature de plasmas a l'aide d'un interferometre Fabry-Perot en ondes millimetriques

    Energy Technology Data Exchange (ETDEWEB)

    Bize, D [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1969-07-01

    The contents of this article, which have been used as a basis for a State doctorate thesis, deal with research into focussing systems of the Fabry-Perot, millimetre wave type. With the help of this equipment, measurements have been made of the electronic density using interferometry in the range from 10{sup 9} to 10{sup 14} electrons/cm{sup 3}, and of the electron temperature by Thomson diffusion, of plasmas formed by laser ionisation and by high frequency. (author) [French] Le contenu de cet article, qui a fait l'objet d'une these d'Etat, se rapporte a l'etude des systemes focalisant de type Fabry-Perot en ondes millimetriques. A l'aide de ces dispositifs, on mesure la densite electronique par interferometrie dans la gamme de densites de 10{sup 9} a 10{sup 14} e/cm{sup 3} et la temperature electronique par diffusion Thomson de plasmas crees par ionisation laser et par haute frequence. (auteur)

  8. Electron spin resonance and E.N.D.O.R. double resonance study of free radicals produced by gamma irradiation of imidazole single crystals; Etude par resonance paramagnetique electronique et double resonance E.N.D.O.R. des radicaux libres crees par irradiation gamma de monocristaux d'imidazole

    Energy Technology Data Exchange (ETDEWEB)

    Lamotte, B [Commissariat a l' Energie Atomique, Grenoble (France). Centre d' Etudes Nucleaires

    1970-07-01

    Gamma irradiation of imidazole single crystals at 300 deg. K gives two radicals. Identification and detailed studies of their electronic and geometric structure have been made by ESR and ENDOR techniques. A study of the hydrogen bonded protons hyperfine tensor is made and let us conclude to the inexistence of movement and tunneling of these protons. The principal low temperature radical, produced by gamma irradiation at 77 deg. K has been also studied by ESR and a model has been proposed. (author) [French] L'irradiation gamma de monocristaux d'imidazole a 300 deg. K conduit a deux radicaux dont l'identification et l'etude detaillee des structures electroniques et geometriques ont ete obtenues par la resonance paramagnetique electronique (RPE) et la double resonance ENDOR. En particulier l'examen des protons de la liaison hydrogene permet de conclure, pour ceux-ci, a l'inexistence de tout mouvement par effet tunnel. De plus, l'analyse des spectres de RPE du radical principal cree par irradiation gamma de l'imidazole a 77 deg. K nous a permis de proposer un modele pour ce radical. (auteur)

  9. Electron density and temperature study of plasmas using a millimeter-wave Fabry-Perot interferometer; Etude de la densite electronique et de la temperature de plasmas a l'aide d'un interferometre Fabry-Perot en ondes millimetriques

    Energy Technology Data Exchange (ETDEWEB)

    Bize, D. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1969-07-01

    The contents of this article, which have been used as a basis for a State doctorate thesis, deal with research into focussing systems of the Fabry-Perot, millimetre wave type. With the help of this equipment, measurements have been made of the electronic density using interferometry in the range from 10{sup 9} to 10{sup 14} electrons/cm{sup 3}, and of the electron temperature by Thomson diffusion, of plasmas formed by laser ionisation and by high frequency. (author) [French] Le contenu de cet article, qui a fait l'objet d'une these d'Etat, se rapporte a l'etude des systemes focalisant de type Fabry-Perot en ondes millimetriques. A l'aide de ces dispositifs, on mesure la densite electronique par interferometrie dans la gamme de densites de 10{sup 9} a 10{sup 14} e/cm{sup 3} et la temperature electronique par diffusion Thomson de plasmas crees par ionisation laser et par haute frequence. (auteur)

  10. Gestion communautaire des ressources naturelles au Bénin (Afrique de l’Ouest : le cas de la vallée du Sitatunga

    Directory of Open Access Journals (Sweden)

    Pricette Dovonou-Vinagbè

    2009-09-01

    Full Text Available Le Bénin, pays de l’Afrique de l’Ouest est confronté à la destruction des terres humides particulièrement dans la partie sud du pays. Les terres humides riches biodiversité sont importantes tant pour les humains que pour milieu naturel. La menace la plus importante est la pression du anthropique. Même si ce territoire est reconnu par la Convention Ramsar, la destruction continue. En 1995 le gouvernement a décidé de créer une aire de gestion communautaire pour ces territoires. L’objectif de  cette recherche est de comprendre les grands défis liés à la mise en œuvre de la gestion communautaire des milieux humides à travers une étude de cas, en l’occurrence celui de la vallée du Sitatunga. Pour atteindre cet objectif, un séjour de 3 mois a été effectué sur le site. Des entrevues semi-dirigées ont été alors réalisées. Les résultats montrent que la vallée du Sitatunga est considérée comme inutile voire nuisible par les populations riveraines rencontrées dans le cadre de l’étude, qui sont davantage préoccupées à se sortir de leur état de pauvreté. Les traditions et valeurs autrefois attribuées à la conservation des milieux humides ont quasiment disparues et l’individualisme est grandissant. Il importe de tenir compte de tous ces facteurs pour espérer véritablement préserver ces milieux. D’un autre côté, parlant de gestion de l’environnement et plus particulièrement de gestion des milieux humides à l’échelle béninoise, le constat n’est pas reluisant. En effet, l’État étant donné son état de sous-développement et donc de manque de ressources, à du mal à coordonner ces activités. Il est de même pour les ONG. La situation est accentuée par l’état des relations entre ONG et structures de l’État qui se considèrent davantage comme des adversaires que comme des partenaires ce qui affecte l’efficacité des activités menées. Pour que la gestion communautaire devienne une

  11. Unconventional Gas Resources in the Paleozoic of Central Europe Ressources de gaz non conventionnels dans le Paléozoïque de l’Europe Centrale

    Directory of Open Access Journals (Sweden)

    Littke R.

    2011-05-01

    Full Text Available Whereas gas production from unconventional reserves has greatly increased over the past decades, there is still a largely unexplored potential in the Paleozoic of Central Europe. For this area, the paper summarizes some important aspects of the geology of tight sandstone gas reservoirs, gas shales and coalbed methane. Tight sandstones with low permeabilities are especially present in the Permian (Rotliegend Formation of The Netherlands and northern Germany, but also in the underlying Carboniferous. There is already active production from some of these reservoirs. Further development greatly depends on understanding of gas charge as well as the regional distribution of porosity and permeability which in turn depend on facies and diagenesis. In contrast exploration for gas shales is just at the very beginning. Whereas Mesozoic shales in the southern Lower Saxony Basin have to be regarded as prime targets due to thickness, maturity and organic matter content, there are additional targets in the Mississippian, but also in older rocks. Currently an international gas shale research programme (Gas shales in Europe, GASH gathers relevant data for these units. Coalbed methane exploration started already about 20 years ago in the Ruhr Basin, but was not successful at that time due to small flow rates. On the other hand, production from abandoned coal mines provided substantial amounts of gas. Due to the abundance of coal seams and the suitable maturity conditions and gas contents, there is a high potential for future substantial coalbed methane in the area. Alors que l’extraction du gaz naturel des gisements non conventionnels a fortement augmenté ces dernières dizaines d’années, un large potentiel de ressources reste inexploré dans les couches paléozoïques de l’Europe Centrale. Cet article présente, pour cette région, quelques aspects importants de la géologie des grès de faible perméabilité (tight gas sands, des gaz de schiste (gas

  12. Study of the machining of uranium carbide rods obtained by continuous casting under electronic bombardment; Etude de l'usinage de barreaux de carbure d'uranium obtenus par coulee continue sous bombardement electronique

    Energy Technology Data Exchange (ETDEWEB)

    Rousset, P.; Accary, A. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1965-07-01

    The authors consider the various methods of machining uranium mono-carbide and compare them critically in the case of their application to uranium carbide obtained by fusion under an electronic bombardment and continuous casting. This study leads them to propose two mechanical machining methods: cylindrical rectification and center-less rectification, preceded by a preliminary roughing out of a cylinder, the latter appearing more suitable. A study of the machining yields as a function of the diameter of the rough bars and of the diameter of the finished rods has shown that an optimum value of the rough bar diameter exists for each value of the finished rod diameter. It is found that the yield increases as the diameter itself increases, this yield rising from 45 per cent to around 70 per cent as the diameter of the rough bars increases from 25-26 mm to 37-38 mm. (authors) [French] Les auteurs envisagent les differentes methodes d'usinage du monocarbure d'uranium et se livrent a une etude critique de celles-ci, dans le cas de leur application a l'usinage de barreaux de carbure d'uranium obtenus par fusion sous bombardement electronique et coulee continue. Cette etude les conduit a proposer deux methodes d'usinage mecanique: la rectification cylindrique et la rectification 'centerless', precedee d'un ebauchage par carottage, la seconde paraissant la plus appropriee. L'etude des rendements d'usinage en fonction du diametre des barreaux bruts et du diametre des barreaux finis, a mis en evidence une valeur optimale du diametre des barreaux bruts pour chaque valeur du diametre des barreaux usines. Elle a montre que le rendement croit lorsque le diametre croit lui-meme, ce rendement passant d'environ 45 pour cent a environ 70 pour cent, lorsque le diametre des barreaux bruts passe de 25-26 mm a 37-38 mm.

  13. The generation of harmonics of the electron cyclotron half-frequency in a double-beam interaction experiment; Generation d'harmoniques de la demi-frequence giromagnetique electronique dans un systeme 'double-faisceau'

    Energy Technology Data Exchange (ETDEWEB)

    Olivain, J [Commissariat a l' Energie Atomique, Fontenay-aux-Roses (France). Centre d' Etudes Nucleaires

    1966-06-01

    The generation of harmonics of the electron cyclotron half-frequency in a double-beam interaction experiment has been studied. A theoretical discussion is presented in which the transverse velocity distributions are represented by Dirac delta functions. The experimental measurements show the structure of the waves generated, for the fundamental mode (( {omega}={omega}/2).ce), i. e., their azimuthal wave number, wave length and radial profile of the oscillating potential, density and current. The quasi-electrostatic character of these waves has been established from these results by evaluating the ratio: vectorial product ({nabla}, E) / scalar product ({nabla}, E) which is always much smaller than unity. Measurements have also been made of the amplitudes and line-widths of several harmonics as well as the growth rate of the first of them. Finally, a number of observations have been made which show that nonlinear wave interactions play an important role in this system and which suggest an interpretation based on this mechanism for the generation of high order harmonics. (author) [French] Nous presentons les resultats obtenus sur la generation d'harmoniques de la demi-frequence giromagnetique electronique dans une experience interraction 'double-faisceau'. Nous discutons theoriquement ce systeme dans lequel les vitesses transversales sont introduites sous forme de distributions de Dirac. Les mesures experimentales ont permis, par le mode fondamental (({omega}={omega})/2.ce), de connaitre la structure des ondes engendrees (nombre d'onde 2 azimutal - longueur d'onde - profil radial du potentiel oscillant, amplitude des perturbations de potentiel, de densite et de courant). Le caractere quasi-electrostatique de ces ondes a pu etre etabli a partir de ces resultats en evaluant le rapport: produit vectoriel ({nabla}, E) / produit scalaire ({nabla}, E) qui reste toujours tres inferieur a l'unite. Les mesures ont egalement porte sur l'amplitude et la largeur des raies ainsi

  14. Aide au suivi du phénomène de dénitrification naturelle pour une gestion durable de la ressource en eau du Béthunois

    Directory of Open Access Journals (Sweden)

    Cherif Boulemia

    2006-11-01

    Full Text Available Les villes sont sujettes à des augmentations de population et d’activité industrielle, ce qui se traduit par une demande supplémentaire en eau. Notre objectif est de développer un outil de gestion et d’aide à la décision pour une meilleure connaissance de la ressource et pour soutenir les décisions de planification dans les services des eaux des moyennes collectivités locales. L’outil permettra une exploitation contrôlée du système aquifère et en particulier la préservation du phénomène de dénitrification naturelle ayant lieu dans la nappe de la craie du Béthunois au Nord de la France. Dans cet article, nous proposons la mise en place d’un tableau de bord à partir d’une plate-forme SIG couplée à un outil de modélisation hydrologique. Nos travaux de recherche sont appliqués au SIVOM de la Communauté du Béthunois.Cities face a substantial increase in population and in industrial activities which entails an increasing demand for water. Our aim is to develop a management and decision-making framework for a better knowledge of the resource and to support the planning and decisions in the water boards of medium-size local communities. The framework will allow the reasoned exploitation of the aquifer system and in particular the preservation of the natural denitrification process which occurs in the chalk aquifer in the Béthunois area in northern France. In this article, we propose the setting-up of a control panel thanks to a GIS platform coupled with a hydrological model. Our research work is applied to the SIVOM of the Béthunois.

  15. Electronic de-multipliers; Demultiplicateurs electroniques

    Energy Technology Data Exchange (ETDEWEB)

    Ailloud, J

    1948-07-01

    The counting of a huge number of events, randomly or periodically distributed, requires the use of electronic counters which can work with a flow of up to 500000 events per second, while mechanical systems have a much lower resolution which leads to an important percentage of losses (non-counted events). Thus, hybrid systems are generally used which comprise an electronic part with fast counting capabilities but low recording capacities, and a mechanical part for the recording of the successive resets of the electronic part. This report describes the basic elementary circuits of these electronic counters (de-multipliers): dividers by 2 and 5 and flip-flop circuits using triode and pentode valves for the counting of events in the decimal system. (J.S.)

  16. Electronic methods for discriminating scintillation shapes; Methodes electroniques de discrimination des formes des impulsions issues de scintillateurs; Ehlektronnye metody diskriminatsii form stsintillyatsii; Metodos electronicos de discriminacion de forma de impulsos de centelleo

    Energy Technology Data Exchange (ETDEWEB)

    Forte, M; Konsta, A; Maranzana, C [European Atomic Energy Community, CCR, ISPRA (Italy)

    1962-04-15

    As reported previously, the scintillation pulse shape, which is characteristic of the excitating particle type (electron, proton, alpha, etc.), can be converted into a pulse-height independent parameter. This displays, by means of a multichannel analyser, the composition of a mixed particle beam which excites the scintillator. This method was successful with several scintillators, both of the organic and the inorganic type. Details are given of the electronic techniques used for converting the pulse shapes. For the simpler case of discrimination between only two classes of pulses (e.g. neutron-gamma discrimination) the use of passive networks has also been considered possible for further improvements and simplifications. A few networks were tried, the main results being that, in the presence of gamma background, the discrimination of recoil protons in liquid scintillators was extended to small pulses of a few decades of photoelectrons and the discrimination of neutron-capture fragments in boronloaded liquids was obtained. Some of these networks operated with pulses of the same polarity, from two of the last dynode, or even with the output from a single electrode. This may be useful when it is convenient to use the anode independently, e. g. for operating fast time circuits. (author) [French] On sait que la forme des impulsions delivrees par un detecteur a scintillations, qui est fonction du type de particule excitatrice (electron, proton, particule alpha, etc.), peut etre convertie en un parametre d'amplitude d'impulsion independant. Cette propriete permet de determiner, a l'aide d'un selecteur multicanaux, la composition d'un faisceau de particules mixte qui frappe le scintillateur. Cette methode a ete utilisee avec succes dans le cas de plusieurs scintillateurs, tant organiques qu'inorganiques. Les auteurs donnent des precisions sur les procedes electroniques employes pour convertir la forme de l'impulsion. Dans le cas le plus simple, celui ou la discrimination

  17. Impact de la forêt sur l’évolution des ressources en eau en moyenne montagne alpine depuis le milieu du XIXe siècle (massif de Chartreuse, France

    Directory of Open Access Journals (Sweden)

    Dominique Dumas

    2012-02-01

    Full Text Available Depuis la révolution industrielle, une grande partie des terres des espaces de moyenne montagne a été abandonnée au profit d’une extension de la couverture forestière. Or, la forêt intercepte et retient un pourcentage plus ou moins élevé des pluies sur son feuillage, diminuant du même coup la quantité d’eau réellement reçue par le sol. Le transfert de l’eau atmosphérique en une eau utilisable comme ressource a donc été progressivement modifié au cours de ces dernières décennies par la transformation progressive du paysage. Dans cette étude, conduite à l’échelle du massif de Chartreuse, la pluviométrie annuelle, le rôle de la forêt dans l’interception des pluies et l’extension de la forêt, sont appréciés tour à tour. L’impact de l’extension de la forêt depuis le milieu du XIXe siècle sur les quantités d’eau perdues pour l’écoulement et les réserves souterraines peut ainsi être évalué. Cette étude montre que, depuis le milieu du XIXe siècle, l’extension de la couverture forestière en Chartreuse aurait accru de presque 100 mm les pertes en eau par les processus d’interception. Et, sur cette même période, cette quantité d’eau perdue n’a pas été compensée par une hausse des précipitations. Au total, le bilan hydrologique a donc été notablement modifié, avec une quantité d’eau disponible pour l’écoulement, ou les réserves souterraines, plus réduite que celle définie traditionnellement à partir des uniques relevés météorologiques.

  18. Traitement des séquelles de brûlures de la main dans les pays à ressources limitées ; notre expérience en république démocratique du Congo

    Science.gov (United States)

    Kibadi, K.; Moutet, F.

    2015-01-01

    Summary Les séquelles de brûlures de la main sont encore fréquentes dans les pays à ressources limitées. Trente-deux patients, représentant 38 mains, ont été admis et traités, entre le 1er décembre 2010 et le 1er mai 2014 aux Cliniques Universitaires de Kinshasa en République Démocratique du Congo (RDC). nous avons observé 22 patients (69 %) dans le groupe de jeunes (patients âgés de moins de 18 ans), et 10 patients (31 %) chez les adultes (18 à 59 ans). Aucun patient dans le groupe de seniors (60 ans et plus) n’a été observé. Dans le groupe de jeunes, la tranche d’âge de 1 à 5 ans a été la plus atteinte avec 13 malades (40 %). l’accident à la maison était le plus fréquent (72 %). le mécanisme de la brûlure était le plus souvent thermique par flammes (51 %) ou par liquide chaud (34 %). les rétractions et brides sont les lésions le plus observées (84 %). la rétraction dorsale globale « main en griffe» est observée chez 40 % de patients traités, associée à des cicatrices hypertrophiques et chéloïdiennes dans 84 % de cas. Chez les 32 mains traitées chirurgicalement, des excision-greffes ont été réalisées dans 43,7 %, des lambeaux locaux dans 43,7 % et des lambeaux à distance dans 12,5 % de cas. A la sortie de l’hôpital, 84 % de « bons » résultats ont été observés. le suivi a été de 18 mois. le traitement des séquelles de brûlures de la main est possible dans ces pays, exemple de la rDC. Mais les défis à surmonter dans ces pays sont nombreux : la faible accessibilité aux techniques actuelles de la chirurgie plastique, la prise en charge initiale inadéquate des brûlures, la pauvreté. PMID:26668560

  19. Measurement of the electron density of a plasma by interferometry with a He - Ne laser ({lambda} = 3.39 {mu}); Mesure de la densite electronique d'un plasma par interferometrie avec un laser He - Ne ({lambda} = 3.39 {mu})

    Energy Technology Data Exchange (ETDEWEB)

    Belland, P [Commissariat a l' Energie Atomique, Fontenay-aux-Roses (France). Centre d' Etudes Nucleaires

    1968-07-01

    The characteristics of the He-Ne gas laser used in a simple interferometric technique have been studied. After passing through the plasma, the beam is reflected back into the laser cavity, and the intensity of the laser itself, modulated by this optical feedback, is used to observe the fringes. Furthermore, owing to the coupling of the two laser transitions 0.63{mu} (red) and 3.39{mu} (infra red), interferences in the infra red can be detected by a simple photomultiplier monitoring the red line. This method has been applied to two plasma machines (E.P.P.E. and SABLIER) for spatial and temporal measurements of the mean electron density. (author) [French] Nous avons etudie les caracteristiques d'un laser a gaz He-Ne utilise dans une technique simple d'interferometrie. La lumiere qui traverse le plasma est reinjectee dans le laser, et l'intensite propre de celui-ci, modulee par cette reinjection, sert a observer les franges. De plus, a cause du couplage des deux transitions laser: 0.63{mu} (rouge) et 3.39{mu} (infrarouge), les interferences dans l'infrarouge peuvent etre detectees par un simple photomultiplicateur sensible au rouge. Nous avons applique cette methode a deux machines a plasma (E.P.P.E. et SABLIER) pour la mesure de la densite electronique moyenne en fonction du temps et de l'espace. (auteur)

  20. Electronic device for measuring the polarization parameter in the {pi}{sup -}p {yields} {pi}{sup 0}n charge exchange reaction on a polarized proton target; Un appareillage electronique destine a la mesure du parametre de polarisation dans la reaction d'echange de charge {pi}{sup -}p {yields} {pi}{sup 0}n sur cible de protons polarises

    Energy Technology Data Exchange (ETDEWEB)

    Brehin, S [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1967-12-15

    An electronic apparatus has been constructed to measure the polarization parameter P{sub 0}(t) in {pi}{sup -}p {yields} {pi}{sup 0}n charge exchange scattering at 5.9 GeV/c and 11,2 GeV/c on polarized proton target. This device insures triggering of a heavy plate spark chamber, allowing visualisation of {gamma} rays from the {pi}{sup 0} decays when the associated neutron offers suitable characteristics in direction and energy. The neutron is detected by an array of 32 counters and his energy is measured by a time of flight method. Electronic circuits of this apparatus are described as test and calibration methods used. (author) [French] Un appareillage electronique a ete realise pour mesurer le parametre de polarisation P{sub 0}(t) dans la reaction d'echange de charge {pi}{sup -}p {yields} {pi}{sup 0}n a 5,9 GeV/c et 11,2 GeV/c sur une cible de protons polarises. Ce dispositif assure le declenchement d'une chambre a etincelles a plaques lourdes, permettant de visualiser les {gamma} de desitegration du {pi}{sup 0}, lorsque le neutron associe presente les caracteristiques convenables en direction et en energie. Le neutron est detecte par un ensemble de 32 compteurs et son energie est mesuree par une methode de temps de vol. Les circuits composant cet appareillage sont decrits ainsi que les methodes d'etalonnage et de verification utilisees. (auteur)

  1. Ressources Minières En Afrique

    International Development Research Centre (IDRC) Digital Library (Canada)

    Tous droits de reproduction, de traduction et d'adaptation réservés ..... 2.1 Production nationale de bauxite en Guinée (1986-2006) ...... et d'une obligation de suivi, de vérification et d'audits annuels transparents » (EIR, 2003d, p. ...... Strategy for African mining », Africa Technical Department Series, Mining Unit, Industry and ...

  2. RESSOURCES ALLOCATION POSSIBILITIES WITHIN HEALTH SERVICES

    Directory of Open Access Journals (Sweden)

    Manea Liliana

    2011-12-01

    Full Text Available The state policy in the health care area must take into account the complexity and specificity of the domain. Health means not only “to treat”, but also “to prevent” and “to recover and rehabilitate the individual physically”. Regardless of the adopted health insurance system, the health system is facing a big problem and this is the insufficient funds necessary to function properly. The underfunding may have various causes, from a wrong health policy, based on “treating” instead of “preventing”, by the misuse of funds. This papers intended to formulate assumptions that underpin the research I am conducting within the Doctoral Research Program held at the Valahia University of Targoviste, which aims at using the management control in increasing the health services performance. The application of the accounting and management control methods in determining health costs can be a beginning to streamline the system. This is also a result of the fact that health care is a public service with specific characteristics: it can not be subject only to market requirements but at the same time he must undergo an administrative savings, representing a typical case of market failure. The increased cost of treatment, as well as the decline in their quality can be determined by the discrepancy between the funding and payment mechanisms. Different payment systems currently available do nothing but perpetuate the shortcomings in the system. Switching to the introduction of cost and budgets by cost centers or object (if solved can be a step forward for a better management of resources. In this context, we consider as a necessity to be imposed the cost analysis on responsibility centers, the definition of the cost object and cost center identification and determination of direct costs and those indirect services to choose the basis for the allocation of cost centers and the determination of each actual cost per diagnosis.

  3. Perception et gestion de l’érosion et des ressources en eau par les agriculteurs et les éleveurs du bassin versant de l’ibicuí (RS, Brésil

    Directory of Open Access Journals (Sweden)

    Rosa Vieira Medeiros

    2008-01-01

    governo. As entrevistas mostram finalmente, que uma melhor gestão dos riscos ambientais passará por uma boa consideração do universo técnico e cultural dos agricultores assim como de suas dificuldades econômicas.L’ouest du Rio Grande do Sul est dominé par la culture du soja, du riz et par l’élevage bovin. Dans la partie sableuse, le milieu est affecté par des phénomènes d’érosion produisant des modelés éoliens spectaculaires (arenização rappelant dans l’imaginaire ceux des déserts. La production agricole est importante ce qui engendre des prélèvements d’eau pour l’irrigation du riz, mais aussi l’utilisation de pesticides pour l’ensemble des cultures. La gestion durable des ressources en eau et en sol de cette région nécessite la mise en place d’action de conservation. Mais un certain nombre de questions se posent alors : comment les agriculteurs perçoivent ces phénomènes ? Constituent-ils pour eux des enjeux ? Comment raisonnent-ils leurs pratiques ? Avec quels réseaux ? Quelles sont les interactions avec les pouvoirs publics ?La méthodologie adoptée s’appuie sur des enquêtes ouvertes réalisées auprès de 23 agriculteurs. Il s’agit de mieux comprendre leur perception de l’environnement, leurs modes de gestion et d’identifier les variables sociales au sein de l’échantillon expliquant des différences de comportement.Les résultats que nous avons obtenus montrent que peu d’agriculteurs perçoivent leurs responsabilités quant à l’érosion des sols et à l’état des ressources en eau. Si des risques de manque d’eau sont perçus par certains, ils sont attribués essentiellement à la sécheresse et non à une surexploitation des ressources, la pollution est négligée. L’érosion des sols dans les zones d’arenização n’est pas considérée comme un enjeu, ces espaces sont improductifs, mais ne menacent pas la rentabilité globale des exploitations. C’est plus l’érosion en nappe au sein des

  4. Using the Spanish Online Resource Aula Virtual de Español (AVE to Promote a Blended Teaching Approach in High School Spanish Language Classrooms / Utilisation de la ressource en ligne espagnole AVE pour favoriser l’approche de l’enseignement hybride

    Directory of Open Access Journals (Sweden)

    Martine Pellerin

    2012-02-01

    Full Text Available The study explores the effectiveness of the implementation of blended teaching (BT by combining the Spanish online resource Aula Virtual de Español (AVE with the face-to-face (F2F delivery approach in second language Spanish programs in two high schools in Alberta, Canada. Findings demonstrate the effectiveness of combining the online resource AVE to the F2F teaching approach to promote BT in the Spanish language classroom. The use of BT approach in the language classroom had a positive impact on the students’ attitudes towards the study of the language, the students’ motivation and their participation levels in class, as well as their use of the target language in the classroom. Moreover, the multimodal experiences provided by the use of the online AVE resource combined with the F2F delivery approach responded more to the different learners learning styles and specific needs. Finally, the use of online AVE in conjunction with F2F teaching was also perceived as an effective tool in the preparation for the International Spanish Diplomas (DELE taken by the students in the more advanced Spanish classes. La présente étude explore l’efficacité de l’enseignement hybride combinant l’utilisation de la ressource espagnole en ligne Aula Virtual de Español (AVE et l’interaction face à face dans les programmes d’enseignement de l’espagnol, langue seconde, dans deux écoles secondaires de l’Alberta (Canada. Les résultats démontrent l’efficacité de la combinaison de la ressource en ligne AVE à la prestation face à face pour favoriser l’approche de l’enseignement hybride dans les cours d’espagnol. L’utilisation de l’approche de l’enseignement hybride dans le cours de langue a eu une incidence positive sur l’attitude des élèves relativement à l’apprentissage de la langue, la motivation des élèves et leur taux de participation en classe, ainsi que leur utilisation de la langue d’apprentissage dans la classe

  5. Création et utilisation de ressources pédagogiques sur support numérique pour l'apprentissage d'une L2 : quelles compétences pour l'enseignant ? Designing and using digital learning resources for second language acquisition: what skills do teachers need?

    Directory of Open Access Journals (Sweden)

    Paul Arthaud

    2006-11-01

    Full Text Available À l'Université de Technologie de Belfort-Montbéliard, des ressources pédagogiques sur support numérique ont été créées afin d'être intégrées au dispositif d'enseignement d'une UV d'anglais destinée à des élèves-ingénieurs. Dans le cadre d'une recherche-action, la nature et la fonction de ces ressources ont été établies à la lumière de connaissances théoriques, et les effets de leur intégration ont fait l'objet de mesures. Cet article se concentre sur les compétences qui ont été requises pour mettre en place ces ressources : compétences dans les domaines de la didactique des langues et de la création de pages HTML. Une ébauche de référentiel métier est proposée. Même si les résultats de cette expérience semblent positifs, la question demeure de savoir s'il est possible d'être en même temps enseignant et concepteur de ressources sur support numérique. Des éléments de réponse se trouvent peut-être davantage du côté de la gestion du temps, de la motivation et des savoir-faire relationnels que du seul côté des compétences informatiques. Cette expérience n'a nullement pour vocation de fixer les règles d'un exemple à suivre. Néanmoins, elle illustre le fait que la recherche-action peut être un moyen efficace de canaliser la diversité des motivations des enseignants impliqués dans des démarches innovantes et de promouvoir la responsabilité déontologique et épistémologique, ce qui contribuera à l'amélioration des pratiques d'enseignement.At the University of Technology of Belfort-Montbéliard, digital learning resources have been designed for and integrated with the pedagogical structure of an English credit course for engineering students. Within an action research procedure, the nature and functions of these resources have been established in the light of theoretical knowledge, and the effects of this integration have been assessed. This article focuses on the skills - in the fields of

  6. Electronic device for measuring the polarization parameter in the {pi}{sup -}p {yields} {pi}{sup 0}n charge exchange reaction on a polarized proton target; Un appareillage electronique destine a la mesure du parametre de polarisation dans la reaction d'echange de charge {pi}{sup -}p {yields} {pi}{sup 0}n sur cible de protons polarises

    Energy Technology Data Exchange (ETDEWEB)

    Brehin, S. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1967-12-15

    An electronic apparatus has been constructed to measure the polarization parameter P{sub 0}(t) in {pi}{sup -}p {yields} {pi}{sup 0}n charge exchange scattering at 5.9 GeV/c and 11,2 GeV/c on polarized proton target. This device insures triggering of a heavy plate spark chamber, allowing visualisation of {gamma} rays from the {pi}{sup 0} decays when the associated neutron offers suitable characteristics in direction and energy. The neutron is detected by an array of 32 counters and his energy is measured by a time of flight method. Electronic circuits of this apparatus are described as test and calibration methods used. (author) [French] Un appareillage electronique a ete realise pour mesurer le parametre de polarisation P{sub 0}(t) dans la reaction d'echange de charge {pi}{sup -}p {yields} {pi}{sup 0}n a 5,9 GeV/c et 11,2 GeV/c sur une cible de protons polarises. Ce dispositif assure le declenchement d'une chambre a etincelles a plaques lourdes, permettant de visualiser les {gamma} de desitegration du {pi}{sup 0}, lorsque le neutron associe presente les caracteristiques convenables en direction et en energie. Le neutron est detecte par un ensemble de 32 compteurs et son energie est mesuree par une methode de temps de vol. Les circuits composant cet appareillage sont decrits ainsi que les methodes d'etalonnage et de verification utilisees. (auteur)

  7. Épidémiologie managériale des facteurs de risque cardiovasculaire ...

    African Journals Online (AJOL)

    2012-03-03

    Il s'agit d'une étude transversale descriptive portant 144 hommes et femmes âgés de 15 ans et plus qui s'est déroulée du 26 février au 03 mars 2012 dans l'aire sanitaire de Zowla. ... It is a descriptive cross-sectional study of 144 men and women aged 15 and over from February 26 to March 3, 2012 in the Zowla area.

  8. Effets cardiovasculaires d'un bloqueur calcique en hypoxie d'altitude

    DEFF Research Database (Denmark)

    Dugas, L; Dubray, C; Herry, J P

    1995-01-01

    High altitude pulmonary oedema can be successfully treated and prevented by calcium channel blockers. Moreover, calcium entering in the cells could explain the congestive phenomena of acute mountain sickness (AMS). These findings led us to study the action of a calcium channel blocker, isradipine...

  9. Browse Title Index

    African Journals Online (AJOL)

    Vol 9, No 1 (1999), Conception et réalisation d'un système d'aide à la décision pour la gestion des ressources naturelles, Abstract ... Vol 11, No 1 (2001), Contrat de Lecture et Revue Electronique : Quel paradigme éditorial, Abstract ... Vol 12, No 2 (2002), Le Document Web, Lisibilité, Structure et Oculométrie, Abstract.

  10. Study of the effect of neutron and electron irradiations on the low temperature thermal conductivity of germanium and silicon; Etude de l'effet des irradiations neutronique et electronique sur la conductibilite thermique aux basses temperatures du germanium et du silicium

    Energy Technology Data Exchange (ETDEWEB)

    Vandevyver, M [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1967-06-15

    The main results obtained from this work are the following: 1 Neutron irradiation (at 300 deg. K) produces lattice defects in germanium and silicon, and a corresponding very large lowering of the thermal conductivity is observed in the low temperature region (4-300 ). The results obtained have been explained with the help of the following hypotheses: for silicon a scattering of phonons by the stress fields produced by the defects; for germanium, a supplementary scattering of the electron phonon type. 2 Annealing treatments carried out on these materials above 373 deg. K restored the thermal conductivity over the whole temperature range of the measurements (4-300 deg. K); in the case of both germanium and silicon there were two steps in the annealing process. 3 A study of the thermal conductivity of germanium (initially P or N) after an electronic irradiation showed that the scattering of phonons could depend on the state of charge of the defects thus produced. (author) [French] Les principaux resultats obtenus au cours de ce travail sont les suivants : 1 Les irradiations neutroniques (a 300 deg. K) introduisent des defauts de reseau dans le germanium et le silicium et l'on observe correlativement pour ces materiaux, une tres importante diminution de conductibilite thermique dans le domaine des basses temperatures (4-300 deg. K). Les resultats obtenus ont pu etre interpretes en admettant principalement: pour le silicium, une diffusion des phonons par les champs de contrainte dus aux defauts; pour le germanium, une diffusion additionnelle du type electron-phonon. 2 Des recuits effectues sur ces materiaux au-dessus de 373 deg. K ont montre une restauration de la conductibilite thermique dans tout l'intervalle de temperature de mesure (4-300 deg. K) et comportant pour le germanium et le silicium, deux etapes de recuit 3 L'etude de la conductibilite thermique de germanium (initialement N ou P) apres une irradiation electronique, a montre que la diffusion des phonons

  11. Contribution to the study of time-resolution in pulse electronics for nuclear physics: phase control circuits; Contribution a l'etude de la resolution en temps de l'electronique impulsionnelle pour physique nucleaire: les circuits de mise en phase

    Energy Technology Data Exchange (ETDEWEB)

    Cortet, J P [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1969-07-01

    Phase control circuits make it possible to improve quite markedly the time resolution in pulse electronics. They replace a random pulse, of which the time of arrival with respect to a reference zero is being measured, by another pulse whose phase is well determined with respect to that, of a clock taken as reference. The time spectrum of the output, delayed, can always be situated inside channels of width {delta}T defined by the clock. The time statistics of the events analyzed is always correct even if the transition time for the circuits defining the channels represents a large fraction of {delta}T: the coding of the time becomes perfect, The phase control circuits, used in precision chronometry, are widely applied in Nuclear Physics since the lime spectra obtained are representative, indirectly, of certain values which are required to be measured with great accuracy. A description is given of: the constitution and operation of phase control circuits; a chain with automatic analysis and automatic reading, built for testing these circuits. Finally the measurement results are given. (author) [French] Les circuits de mise en phase permettent d'ameliorer notablement la resolution en temps de l'electronique impulsionnelle. Ils substituent a une impulsion aleatoire, dont on cherche a mesurer l'instant d'arrivee par rapport a un instant pris pour origine, une autre impulsion dont la phase est bien determinee par rapport a celle d'une horloge prise comme reference. Le spectre temporel de sortie, retarde, peut toujours etre situe a l'interieur des canaux de largeur {delta}T, definis par l'horloge. La statistique temporelle des evenements analyses est toujours correcte, meme si la duree de transition des circuits definissant les canaux represente une grande fraction de {delta}T: le codage de temps devient parfait. Les circuits de mise en phase, utilises en chronometrie fine, sont tres employes en Physique Nucleaire car les spectres temporels oblenus sont representatifs

  12. Study of a pulsed discharge in hydrogen using the far ultraviolet emission of an additional element: electron temperature measurement; Etude d'une decharge pulsee dans l'hydrogene a partir de l'emission dans l'ultraviolet lointain d'un element additionnel: mesure de la temperature electronique

    Energy Technology Data Exchange (ETDEWEB)

    Schwob, J L [Commissariat a l' Energie Atomique, Fontenay-aux-Roses (France). Centre d' Etudes Nucleaires

    1967-06-15

    Ionization and excitation of an additional element in a pulsed annular discharge in hydrogen at low pressure (T.A.2000) are described by means of a simple coronal type analytical model. This model allows us to interpret the time variation of the intensity of spectral lines observed in the vacuum ultraviolet region. From this analysis two methods of electron temperature determination are deduced. The first method is based on the apparition time measurement of the intensity maximum for the spectral lines emitted from successive ions of the additional element (nitrogen). In the second method the electron temperature is determined from the intensity ratio of two spectral lines of an alkali-like ion. The transition couples (2s-2p, 2s-3p) and (2s-2p, 3s-3p) of C IV, N V and O VI have been used. The results obtained with these two independent methods are in good agreement. The electron temperature varies from a few electron-volts at the beginning of the discharge, to 70 eV at the time of N V emission (at 55 {mu}s), before the current maximum in the discharge (at 170 {mu}s). (author) [French] On etudie l'ionisation et l'excitation d'un element additionnel dans une decharge annulaire pulsee dans l'hydrogene sous faible pression (T.A.2000) a ralde d'un modele analytique simple du type coronal. Ce modele permet d'interpreter l'evolution de l'intensite des raies spectrales observees dans l'ultraviolet lointain. On deduit de cette etude deux methodes de determination de la temperature electronique. La premiere est basee sur la meaure des temps d'apparition des maximums d'intensite des raies emises par les ions successifs de l'element additionnel (azote). Dans la deuxieme methode la temperature est determinee a partir du rapport d'intensite des deux raies d'un ion alcalinoide. On a utilise les couples de transitions (2s-2p, 2s-3p) et (2e-2p, 3s-3p) des ions C IV, N V et 0 VI. Les resultats obtenus par ces deux voies independantes montrent un assez bon accord. La temperature

  13. Applications of electrical resistivity measurements to research into the purification of uranium using floating molten zone by electronic bombardment; Applications des mesures de resistivite electrique a l'etude de la purification de l'uranium par fusion de zone flottante par bombardement electronique

    Energy Technology Data Exchange (ETDEWEB)

    Pascal, J L [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1964-02-01

    The purification of uranium has been achieved by zone melting. Because of the high affinity of uranium towards elements such as oxygen, contamination has been avoided by adopting the floating zone technique and by working under high vacuum. The difficulties created by the deformations of uranium rod, which are caused by anisotropy of dilatation of phases {alpha} and {beta} and allotropic transformations {alpha} {r_reversible} {beta} and {beta} {r_reversible} {alpha}, have been overcome by the use of electron bombardment stabilized by feedback. A rough control of the purification was obtained by micrographic examination, microhardness measurements, and tests of secondary recrystallization, allowed us to appreciate the new degree of purity of the uranium obtained. The investigation of the purity degree was pursued by electrical resistivity measurements at 20 deg. K. But one had to take care in the interpretation of those measurements of the anisotropy of the uranium resistivity and the influence of structure on residual resistivity. Those measurements have led us, by determination of single crystal and uranium resistivity, to be able to distinguish between the principal resistivity against axis [100] and [010]. (author) [French] La purification de l'uranium a ete realisee par l'application de la methode dite de la zone fondue. L'uranium etant particulierement reactif vis-a-vis d'elements tels que l'oxygene, les risques de contamination ont ete supprimes en adoptant la technique de la zone flottante et en operant sous vide eleve. Les difficultes creees par les deformations du barreau d'uranium, dues a l'anisotropie de dilatation des phases {alpha} et {beta} et ou passage des deux points de transformation allotropiques {alpha} {r_reversible} {beta} et {beta} {r_reversible} {alpha}, ont pu etre surmontees par l'emploi du chauffage par bombardement electronique, stabilise par un systeme tres simple de contre reaction. Un premier controle de la purification effectue par

  14. Desserte ferroviaire à grande vitesse, activation des ressources spécifiques et développement du tourisme : le cas de l’agglomération rémoise High speed rail service, specific resources activation, and tourist development: the case of Rheims

    Directory of Open Access Journals (Sweden)

    Sylvie Bazin

    2012-12-01

    Full Text Available La LGV est-européenne a été mise en service le 10 juin 2007. Les acteurs économiques des territoires desservis attendent beaucoup de cette arrivée notamment en matière de développement des tourismes urbain et d’affaires. Mais un tel développement n’est pas automatique. C’est l’appropriation collective de l’innovation que constitue la desserte à grande vitesse dans un territoire qui est au coeur de ses effets positifs. En effet, cette appropriation collective constitue une innovation relationnelle de laquelle peuvent naître des innovations de services complémentaires en matière de tourisme susceptibles de valoriser les ressources spécifiques existantes (patrimoine historique, culturel, gastronomique, etc.. Ainsi, si l’existence de ressources spécifiques joue un rôle pour les villes desservies, les efforts coordonnés des acteurs pour favoriser la “mise en tourisme” de la ville sont également décisifs. L’analyse est illustrée par le cas de l’agglomération rémoise.The East European High-Speed Rail started on June 10, 2007. Economic actors of beneficiary territories are expecting a lot of positive effects such as the development of urban and business tourisms. But such development is not automatic. The collective appropriation of the innovations linked to a High-Speed Rail Service seems to be central for generating positive effects. Indeed, this collective appropriation constitutes a relational innovation, which may give birth to additional services innovations in tourism that could enhance the value of existing specific resources (historical, cultural, gastronomic, etc. and turn them into assets. Thus, if the availability of specific resources plays a specific role for the connected cities, coordinated efforts of actors to promote the tourist development of the city are also decisive. We will illustrate our subject with the case of Rheims.

  15. Les algues sont-elles une ressource marine à exploiter pour développer durablement l’espace caribéen ? Can algae be a sea resource to be exploited to have a sustainable development of Caribbean?

    Directory of Open Access Journals (Sweden)

    Sophie Litzler

    2010-12-01

    Full Text Available L’algue est une ressource marine peu étudiée par la géographie ; elle offre pourtant des potentialités de développement économique. Les macro-algues cultivées à des fins alimentaires sont une alternative à la pêche. Les micro-algues constituent une biomasse valorisable : molécule pharmaceutique, Oméga 3 et biocarburants. De ces différents usages naît la question suivante : les algues sont-elles une ressource marine à exploiter pour développer durablement les territoires de la zone intertropicale ? Nous présenterons tout d’abord l’algoculture à l’échelle mondiale en soulignant le faible poids de cette activité dans le bassin caribéen. Puis nous montrerons que l’algoculture s’inscrit dans un processus de développement durable en assurant un revenu à des communautés rurales (Petites Antilles. Enfin, dans une approche comparative (États-Unis, nous verrons que l’espace caribéen est une région de projets et d’aménagements durables qui a des atouts pour développer l’algoculture : exposition solaire, hautes températures, proximité de la recherche américaine.Algae as sea resource have not been largely explored in Geography, yet it offers the potential for economic development. Macro-algae are cultivated for food purposes and they can substitute for fishing. Micro-algae can be valued as biomass: “nutraceutics”, Omega 3, biofuel. These various utilizations raise a question: are algae a key to a sustainable development in intertropical islands? We shall present Algaculture on a global scale, while emphasizing its low importance in the Caribbean. Then we shall show how algaculture can be part of a process of sustainable development by providing revenue to rural communities (Lesser Antilles. Finally, in a comparative approach (with the US, we shall see that the Caribbean Region has a number of assets for algaculture that make it suitable for sustainable projects and infrastructures: solar exposure

  16. Les connaissances au quotidien : perceptions et savoirs des populations riveraines de l’Amazonie sur leurs ressources halieutiques Conhecimentos no cotidiano : percepções e saberes de populações ribeirinhas da Amazônia sobre seus recursos haliêuticos  Knowledge in everyday life: perceptions and knowledges of riparian Amazonian populations on their fishery resources

    Directory of Open Access Journals (Sweden)

    S. Paquet

    2011-12-01

    Full Text Available Dans cet article nous nous sommes intéressés à la la pêche vivrière et artisanale pratiquée par les riverains de l’Amazonie. Les résultats présentés, touchant le savoir traditionnel de ces populations, leurs perceptions des changements environnementaux et de l’évolution des ressources halieutiques, ainsi que les solutions à y apporter, proviennent de deux questionnaires administrés à douze communautés du bassin du Tapajós. Ces résultats apportent un nouvel éclairage sur les enjeux liés à la gestion des ressources halieutiques et soulèvent les lacunes empêchant une réele appropriationdes problèmes environnementaux et l’émergence locale de solutions. Nous avons en effet mis en évidence que le déboisement et l’érosion des berges étaient perçus comme les plus importants changements environnementaux observés au fil du temps. La diminution de l’abondance et/ou la réduction des tailles des poissons a également été signalée par les personnes rencontrées. Le manque de lien entre les changements observés sur les écosystèmes naturels et ceux observés sur la ressource halieutique a attiré notre attention. En conséquence, toute intervention visant l’élaboration et/ou l’implantion de méthodes durables d’exploitation des ressources halieutiques doit absolument passer par une activité préalable d’information. Ceci dans le but de générer une appropriation locale des problèmes environnementaux et de favoriser l’émergence de solutions au sein des communautés concernées.Nesse artigo nós nos interessamos a pesca artesanal praticada pelos ribeirinhos da Amazônia. Os resultados apresentados, tocando o saber tradicional dessas populações, suas percepções sobre as mudanças ambientais e a evolução dos recursos haliêuticos, assim como as soluções para essas mudanças, provêm da análise de dois questionários aplicados em doze comunidades da bacia do Tapajós. Esses resultados lançam uma

  17. The World's Present And Future Resources Of Protein Available For Human Nourishment, And The Possibilities For Utilizing These Resources; Les ressources mondiales actuelles et futures en proteines disponibles pour l'alimentation de l'homme - Leurs possibilites d'utilisation

    Energy Technology Data Exchange (ETDEWEB)

    Pion, R.; Fauconneau, G. [INRA, Centre National de Recherches Zootechniques, Jouy-en-Josas, Yvelines (France)

    1968-07-01

    necessaire a la satisfaction de ses besoins. Ces differents acides amines indispensables sont synthetises par les organismes vegetaux terrestres ou aquatiques; les acides amines indispensables sont en majeure partie incorpores dans des proteines vegetales, qui sont soit consommees telles quelles par l'homme, soit transformees, avec un rendement assez faible, en proteines animales utilisees ulterieurement par l'homme. Les ressources en proteines ainsi mises a la disposition de l'homme sont actuellement insuffisantes et l'augmentation de la population mondiale rend necessaires aussi bien une augmentation de leur production qu'une amelioration du rendement de leur utilisation. L'inventaire des diverses sources de matieres azotees alimentaires et l'etude de leur composition en acides amines (principal facteur de qualite) montrent qu'il existe de nombreux moyens d'augmenter les ressources dont peut disposer l'homme, aussi bien par l'amelioration des techniques agricoles que par la fabrication de complements par l'industrie. La production vegetale peut etre amelioree surtout grace a l'irrigation, a l'utilisation d'engrais (en particulier azotes) et a l'amelioration genetique des graines, en vue de l'obtention de proteines de meilleure qualite a partir des especes actuellement cultivees aussi bien que de l'utilisation de plantes de composition interessante qui ne sont pas exploitees actuellement. La production et l'utilisation accrues de complements d'origine industrielle (acides amines de synthese notamment) doivent contribuer a ameliorer le rendement de l'utilisation des proteines d'origine vegetale par les monogastriques (homme, porc, volaille). Enfin, certaines proteines de bonne qualite (poissons, lait) devraient etre dans une plus grande proportion utilisees directement par l'homme. La technologie permet actuellement la bonne conservation de ces proteines. (author)

  18. Les possibilités d'utilisation ciblée des ressources de la Responsabilité Sociale des Entreprises dans le secteur vinier dans le but d'améliorer la durabilité et la spécificité culturelle des régions viticoles

    Directory of Open Access Journals (Sweden)

    Murdjeva Ivana

    2017-01-01

    Full Text Available Ces dernières années, la responsabilité corporative sociale (RCS marque une certaine croissance dans l'intérêt des entreprises envers l'intégration dans des causes d'intérêt social dans leurs pratiques commerciales. L'on note un intérêt accru envers les sujets liés à l'éducation, l'écologie, la santé, l'amélioration de la sensibilisation des consommateurs, l'amélioration des conditions de travail et, tout dernièrement, aux sujets et aux initiatives visant la conservation et la protection du patrimoine culturel matériel et immatériel. Diverses entreprises et producteurs, dans leur plupart de petite et moyenne envergure, dirigent leurs ressources vers un travail avec des groupes et des communautés locales, afin d'améliorer le milieu et de créer une motivation pour la conservation durable des emplois et l'augmentation de l'engagement professionnel et des compétences des personnes employées dans la production. Les secteurs publics ayant contact avec la culture, l'art, la préservation de l'identité et des tra-ditions manquent encore de popularité, y compris les productions spécifiques aux régions, la préservation du milieu et la conservation des phénomènes de la nature, la préservation de la culture des communautés locales et leur intégration dans un échange d'ordre global.

  19. The Combined Use of Autoradiographic and Electron Microscopic Techniques for Studies on Ultra-Thin Sections of Tritium-Labelled Cells of the Intestinal Epithelium; Emploi Combine de l'Autoradiographie et du Microscope Electronique pour L'Etude de Coupes Ultra-Fines de Cellules Tritiees de l'Epithelium Intestinal; 0421 043e 0432 043c 0435 0414 ; Empleo Combinado de Tecnicas de Autorradiografia y de MicroscopiA Electronica para Estudiar Cortes Ultrafinos de Celulas Tritiadas del Epitelio Intestinal

    Energy Technology Data Exchange (ETDEWEB)

    Hampton, J. C. [Division of Experimental Biology, Baylor University College of Medicine, TX (United States); Quastler, H. [Brookhaven National Laboratory, Upton, Long Island, NY (United States)

    1962-02-15

    The high resolution now obtainable in sectioned cells studied in the electron microscope offers some promise of visualizing some of the intracellular events leading to the synthesis of proteins. The specificity of incorporation of tritiated thymidine into DNA provides a system which can be accurately followed with respect to time and localization within the cell. The work to be reported here demonstrates that it is possible to study ultra-thin sections of labelled cells in the electron microscope, to remove the specimen after suitable electron micrographs have been taken, to apply a coating of emulsion sufficiently thick to obtain an autoradiograph but still thin enough' to permit re-examination of the specimen in the electron microscope and to obtain electron micrographic images of autoradiography of cells previously recorded. The autoradiographic emulsion was applied as follows: a thin film was formed by dipping a small wire loop into liquid emulsion and transferring the film by passing the loop over the mounted specimen which was fixed to the top of a small plastic peg. Adequate control can be achieved by taking a one-half micron section after each ultra-thin section during sectioning, mounting it on a glass slide and applying conventional autoradiographic techniques. Because of the fragile nature of ultra-thin sections, the yield of successful autoradiographs is quite low. In spite of this objection it is expected that with improvements in skill and techniques the method will facilitate a better understanding of vital cell processes. (author) [French] Le haut degre de resolution que l'on peut maintenant obtenir dans l'etude des coupes de cellules au microscope electronique offre quelque possiblite d'observer certains des processus intracellulaires qui menent a la synthese des proteines. Le fait que la thymidine tritiee s'incorpore a l'ADN de facon specifique permet de suivre avec precision le deroulement d'un autre processus dans le temps et leur localisation

  20. Energy Resources of Water-Bearing Geopressured Reservoirs-Tertiary Formations, Northwestern Gulf of Mexico (Summary Ressources énergétiques des réservoirs aquifères à pressions géostratégiques dans les formations tertiaires du golfe du Mexique (résumé

    Directory of Open Access Journals (Sweden)

    Bebout D. G.

    2006-11-01

    Full Text Available Estimates for the total gas resource in place in geopressured Tertiary sandstone reservoirs along the United States Gulf Coast range from 3,000 to 100,000 tcf 185 to 2,832 trillion cu m. This wide range in estimates was the incentive for initiative research effort in Texas and Louisiane to obtain more reliable data on all aspects of developing the available heat and hydraulic energy present in these aquifers in addition to the methane. All resource calculations are based on interpretations of total sandstone thickness, lateral extent of reservoirs, porosity and permeability, reservoir drive, salinity, temperature, pressure, and methane solubility. Diverse estimates arise from inadequate knowledge concerning these critical parameters. Regional and detailed local geologic studies have been conducted ta delineate prospective areas for testing the geopressured resource. A prospective area should have reservoir volume of 3 Cu mi (12 cu km, minimum permeability of 20 mD, and fluid temperatures of 300°F (150°C. A geothermal designed test well has been drilled in Brazoria County, Texas, in order to test the potential of producing up to 40,000 barrels of water per day from a geopressured reservoir. The reservoir consists of 250 to 300 ft (75 to 90 m of sandstone with core permeabilities between 40 and 60 mD and fluid temperatures from 300 to 350°F (159 to 177°C. The test period will continue for a 2-year period and, with other designed tests in Texas and Louisiana will provide invaluable data concerning high-volume production over long periods of time. Les estimations pour les ressources totales de gaz dans les réservoirs sableux tertiaires à pressions géostatiques le long de la Gulf Coast des Etats-Unis sont corises entre 3000 et 100 000 tcf, soit 85 à 2832. 10. 12 m3. Cette large incertitude a incité la mise en oeuvre d'un effort extensif de recherche au Texas et en Louisiane en vue d'obtenir des données plus sûres sur tous les aspects du d

  1. DIAGNOSTIC SPECTROSCOPIQUE EN TEMPERATURE ELECTRONIQUE DES PLASMAS PHOTOIONISES

    Directory of Open Access Journals (Sweden)

    A. K Ferouani

    2009-12-01

    Full Text Available In this work, we are interested in the diagnostics in electronic temperature of a plasma purely photoionized, based on the intensity ration of lines emitted by ions helium-like, witch have an atomic number Z relatively small. We considered the three lines corresponding to the transitions starting from the excited levels 1s2l towards the fundamental level 1s2 1S0, like appropriate lines. More precisely, the line of resonance w due to the transition 1s2p 1P1 1s2 1 S0, the line of intercombinaison (x,y 1s2p 3 P2,1 1s2 1 S0 as well as prohibited line z due to the transition 1s2 3 S1 1s2 1 S0. These lines appear clearly in the spectra of astrophysical plasmas. As helium-like ion, we chose two, the oxygen O6+ (Z=8 and neon Ne8+ (Z=10. We carried out calculations of the ration of lines intensity G=(zxy/w of O6+ and Ne8+ according to the electronic temperature in the range going from 105 to 107 K. We will see that, like it was shown by Gabriel and Jordan in 1969, this intensity ration can be very sensitive to the temperature electronic and practically independent of the electronic density. Consequently, the ration G can be used to determine in a reliable way the electronic temperature of plasma observed.

  2. Fundamental study of ionization and dissociation processes caused by electron impact in aromatic molecules; application of the quasi-equilibrium theory to phenanthrene and to methylphenanthrenes; Etudes fondamentales des processus d'ionisation et de dissociation des molecules aromatiques par impact electronique et application de la theorie du quasi-equilibre au phenanthrene et aux methyl-phenanthrenes

    Energy Technology Data Exchange (ETDEWEB)

    Nounou, P [Commissariat a l' Energie Atomique, Grenoble (France). Centre d' Etudes Nucleaires

    1969-07-01

    behaviour under ionizing radiations of the studied compounds. (author) [French] La theorie du quasi-equilibre n'a ete appliquee jusqu'a present qu'a la seule famille des hydrocarbures aliphatiques en chaine droite. Nous avons donc essaye de l'etendre au phenanthrene et au methyl-phenantrene, c'est-a-dire, d'une part a des molecules aromatiques et d'autre part a des molecules ayant un tres grand nombre de degres de liberte. Dans une premiere partie nous avons tente d'interpreter de facon methodique les processus d'ionisation et de dissociation des molecules phenanthreniques. Cette premiere etude experimentale du comportement des composes sous impact electronique, et son interpretation, nous ont fourni de precieux renseignements sur de profonds changements de structure des ions moleculaires et fragmentaires, voire d'excitation des molecules etudiees. L'etude approfondie des pics metastables a ensuite confirme les processus de dissociation precedents, tout en precisant certaines grandeurs thermodynamiques relatives aux reactions de decomposition. Etudes des processus d'ionisation, puis de dissociation, et enfin des pics metastables, constituent les trois temps d'une methode generale d'interpretation de la fragmentation en spectrometrie de masse. Pour donner a cette methode son assise theorique nous avons ete amenes a elaborer les diagrammes moleculaires de chacun des composes etudies, montrant ainsi l'aide efficace que peut presenter la Mecanique Quantique pour l'etude des etats excites et ionises. Dans une seconde partie, nous avons calcule les spectres de masse du phenanthrene et des methyl-phenanthrenes a partir des expressions des constantes de reaction donnees par ROSENSTOCK. Pour ce faire, nous avons propose de nouvelles methodes de calcul des facteurs de frequence, tant pour les molecules aliphatiques que les aromatiques. Si le bon accord generalement observe entre le calcul et l'experience ne peut etre attribue a coup sur a l'exactitude de la theorie, il n'en demontre

  3. L’ÉTUDE CLINIQUE DU MOIS TECOS : confirmation de la sécurité cardiovasculaire de la sitagliptine

    OpenAIRE

    SCHEEN, André; PAQUOT, Nicolas

    2015-01-01

    Summary : The cardiovascular safety of sitagliptin has been evaluated in TECOS («Trial Evaluating Cardiovascular Outcomes with Sitagliptin»). TECOS recruited patients with type 2 diabetes and a history of cardiovascular disease who received, as add-on to their usual therapy, either sitagliptin (n = 7.257) or placebo (n = 7.266), with a median follow-up of 3 years. The primary cardiovascular outcome was a composite of cardiovascular death, nonfatal myocardial infarction, nonfatal stroke, or ho...

  4. Is er een plaats voor voedingsmiddelen verrijkt met fytosterolen bij cardiovasculair risicomanagement? Kritische analyse van de bewijskracht voor cholesterolverlaging

    NARCIS (Netherlands)

    Alting, E.K. (Kim); Riphagen, LM (Laura); Schuiling-Veninga, C.C.M. (Nynke); Brouwers, J.R.B.J. (Koos); Woerdenbag, Herman

    2017-01-01

    Is there a place for phytosterol-enriched food products in cardiovascular risk management? Critical analysis of the evidence for cholesterol reduction OBJECTIVE To analyse the literature of the past decade regarding the cholesterol-lowering effect of phytosterol-enriched food products. DESIGN A

  5. Tour de tailleaugmenté et facteurs de risque cardiovasculaire [Increased waist circumference and cardiovascular risk factors

    Directory of Open Access Journals (Sweden)

    Salima TALEB

    2015-12-01

    Full Text Available Introduction. Obesity evaluated by body mass index (BMI is a recognized cardiovascular risk factor. Studies have shown that adipose tissue deposition in visceral level, reflected by increased waist circumference itself was a cardiometabolic risk factor. Objective. The relationship was studied between a high waist circumference and a cardiovascular risk. Material and Methods. A descriptive and analytical cross-sectional survey was conducted among 200 subjects in 2014 in Tebessa. The questionnaire allowed us to gather the following information: anthropometric measurements, dietary habits, physical activity, smoking, personal and family history ... Blood sample was realized to determine some biochemical parameters. Results. In this study, 60.5% of the subjects had a pathological waist, women were more affected than men (72.86% vs 31.67%, p <0.0001. This prevalence peaked between 47-66 years (p <0.0001. Pathological waist circumference was a predictor of cardiovascular disease (CVD, (RR = 1.71, P = 0.028. This study revealed that 16.53% of subjects with a pathologicalwaistlines had diabetes, 55.5% were hypertensive, 49% had hypertriglyceridemia, 46% low HDL, and 18 % high LDL. In normal weight subjects, 22% had pathological waistline. Conclusion. The prevalence of abdominal obesity is higher among patients consulting in private practice in Tébessa, this requires screening and awareness of people with pathological waistline.

  6. MERIP - Design of Production Systems with focus on Human Ressources

    DEFF Research Database (Denmark)

    Jacobsen, Peter; Knudsen, Mads Kristian Lund

    1998-01-01

    ", "Employee-activated Production Development - MAPU", "Integrated Production Systems - IPS" and "Strategic Development of Staff - SUM". MERIP (Human resources in production) is a continuation of this type of projects, aiming at increasing the competitive power of the companies. However MERIP scientists want...... to involve the human resources in the production in new ways. Therefore the objective of the project is to develop methods for design of production systems, that use every possibility in human resources supported by the technology aiming at increasing the competitive power of the companies. The task force......The way in which the Industry has involved the human resources in production systems, has changed in last decades. Previously the human resources were mainly considered as means to link together the technical systems, while today they are key resources responsible for development, planning...

  7. Gestion communautaire des ressources naturelles dans le Parc ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    En 2002, le Mozambique, l'Afrique du Sud et le Zimbabwe ont signé un accord établissant le Parc transfrontalier du Grand Limpopo (Greater Limpopo Trans Frontier Conservation Area), qui relie entre eux des parcs nationaux des trois pays et un ensemble de terres relevant pour la plupart de régimes fonciers communaux.

  8. AIDS Resource Directory and Repertoire de ressources sur le SIDA.

    Science.gov (United States)

    Department of National Health and Welfare, Ottawa (Ontario).

    This set of documents presents directories of resources on the topic of Acquired Immune Deficiency Syndrome (AIDS) available in Canada in English and in French. The first section in each directory contains a list of names, addresses, and telephone numbers of organizations from which readers may obtain the listed resources. Resources are then…

  9. CERN HUMAN RESSOURCES 1999 FRENCH VERSION NOW AVAIABLE

    CERN Multimedia

    Division du Personnel

    1999-01-01

    A report on CERN Human Resources is published once every two years. The version of the 1999 report is now available in French and in English: in your divisional secretariat for paper copieson the Web: http://www.cern.ch/HRreportIn its foreword, the Director-General addresses some key issues:'Many (…) key personnel are now steadily approaching retirement. (…) More efficient working methods and new technology can absorb not all the natural depletion. New blood is vital, and about a hundred new people are taken on each year'About the RSL programme, he says:'… More than 30 additional posts have been opened by this voluntary scheme. This programme displays the excellent mutual understanding that has been carefully built up between CERN management and staff. This harmonious atmosphere bodes well for continued success.'The Human Resources 1999 report gives information on a lot of subjects:general information on CERN's aim and the organisation of its operations,major changes in recent years...

  10. Balanced Ecological Use of Biomass Ressources in Denmark

    DEFF Research Database (Denmark)

    Meyer, Niels I; Nielsen, Vilhjalmur; Christensen, B. T.

    1996-01-01

    Renewable energy sources play a central role in the creation of a sustainable energy development. Due to the fluctuating nature of several renewable energy sources such as solar, wind and waves, new methodologies are needed for planning of energy supply systems. When biomass or hydro power sources...... straw and animal manure (for biogas) from agriculture. This paper describes the potential of biomass in the Danish energy supply system three to four decades ahead. The use of biomass for energy purposes may however conflict with the need to maintain soil quality of arable fields. Concerned ecological...... farmers claim that crop residues and animal manure should all be returned to the fields in order to improve soil organic matter levels. Consequently they oppose the export of these biomass resources for energy purposes with subsequent combustion and loss of carbon and nutrients. This conflict involves...

  11. Ressources hydriques du bassin synclinal d'Essaouira (Maroc

    Directory of Open Access Journals (Sweden)

    Youbi, N.

    2000-08-01

    Full Text Available Not available.La cuenca sinclinal de Essaouira está constituida por un conjunto de unidades sinclinales, siendo las principales la de Bouabout (en la zona frontal y la de Essaouira (en la zona trasera. Estas unidades contienen las reservas de agua más importantes de la región que se encuentran en el acuífero Cenomaniense-Turoniense de Bouabout y en los acuíferos del Turoniense y Plio-Cuaternario de la zona sinclinal de Essaouira. El principal río que atraviesa esta cuenca es el denominado Igrounzar (en la zona frontal y Ksob (en la zona trasera. Es un río perenne gracias a las fuentes Cenomanienses-Turonienses de la zona frontal. Más del 50 % del volumen de agua de este río fluye entre los meses de noviembre y enero. Medidas de aforo diferenciales efectuadas a lo largo del ciclo hidrológico 1990-1991 (Fekri, 1993 demuestran que el Oued Ksob alimenta los acuíferos Plio-Cuaternarios y turoniense por flujos de 42 l/s y 64 l/s, respectivamente. El estudio hidrogeológico de los acuíferos de esta cuenca muestra que las aguas subterráneas fluyen del SE hacia el noroeste en el acuífero Plio-Cuaternario, y hacia el noroeste, el noreste y el oeste a nivel del acuífero Cenomaniense-Turoniense. El estudio hidroquímico permite identificar el origen de las mineralizaciones de las aguas, sus facies y sus calidades. La hidrología isotópica permite estimar las áreas de recarga de los acuíferos y sus interacciones, y definir las relaciones entre las dos unidades que constituyen la cuenca. También muestra que la recarga de los acuíferos por las lluvias eficaces se produce sin una notable evaporación.

  12. L'enseignant de FLE et les ressources Internet

    Directory of Open Access Journals (Sweden)

    Mario Tomé

    2006-04-01

    Full Text Available This article present the role of the teacher in the new contexts of formation opened by new information technologies and communication (in particular Internet within the framework of the numerical universities or the virtual campuses. This article proposes in also a classification of the teaching resources in relation to the supports and the devices not to confuse the various materials which make part of Internet. The many resources, supports and achievements announced in this ar ticle and available on line can give tracks to teachers and researchers in the field of the TICE.

  13. etude socio-anthropologique de la gestion des ressources naturelles

    African Journals Online (AJOL)

    SECRETARIAT

    Le Burkina Faso est un pays sahélien dont l'économie est essentiellement agricole. ... dégradation sont, entre autres, l'érosion hydrique et éolienne, les changements climatiques, les actions .... Figure 3 : Présentation globale de la zone.

  14. Developpement du systeme de gestion des ressources humaines ...

    African Journals Online (AJOL)

    Health workers are facing several problems in order to be successful in their interventions. Lacs Health District faced different issues in human resources management (HRM) and a lot what done to deal with them. In order to sustain, it is important to know the level of its human resources management systems development.

  15. Ressources pour chercheurs de pays en développement

    International Development Research Centre (IDRC) Digital Library (Canada)

    Mélanie Brunet

    permanent à cette dernière, elle archive tous ses articles dans PubMed Central. ... Redalyc (Red de Revistas Científicas de América Latina y El Caribe, España y ... disponibles en format texte et il est aussi possible de les télécharger en PDF.

  16. impacts du changement climatique sur les ressources en eau en

    African Journals Online (AJOL)

    AISA

    Le Bandama, composé de trois principaux affluents (le ... l'application des lois physiques régissant le système .... et le secteur des savanes (Korhogo). MODELE ... GFD3 et UK89 dans les secteurs phyto-géographiques en l'an 2075. Variation ...

  17. Stratégies paysannes de conservation de quelques ressources

    African Journals Online (AJOL)

    AISA

    et les ménages. Les pratiques de conservation des semences les plus courantes observées sont ... Il s'agit de la cendre, du jus d' Azadirachta indica, du sable fin, des .... palmier à huile (Elaeis guineensis L.) et les ..... Elles sont essentiel-.

  18. Migration, pauvreté rurale et gestion communautaire des ressources ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    La migration, les déplacements et les réinstallations forcées sont loin d'être des phénomènes nouveaux au Cambodge. Après des années d'agitation et de troubles de l'ordre civil, et en raison de la croissance rapide de la population et du développement agricole, la plupart des terres irriguées et inondables au Cambodge ...

  19. A CLASICAL APPROACH TO HUMAN RESSOURCES IN ROMANIAN SMEs

    Directory of Open Access Journals (Sweden)

    Alexandra Maria FIRA

    2012-01-01

    Full Text Available The main objective of our paper is the study of human resources management in SMEs in Dolj County. Through our research we emphasize and demonstrate the importance of human resources in the maintaining process of stability and in perpetuating the viability of this dynamic sector – the one of SMEs. Thus, the theoretical concepts are grounded both through theory and national and international practices, and through the actual data obtained from the research that will be carried out in the field. The practical implications of our research reflect in the analysis and interpretation of the research results carried out on 516 employees from SMEs in Dolj County, as well as in the recommendations elaborated based on a set of variables established according to the importance of the employees’ role in the enterprises as bearers of initiative and generators of innovation. Therefore, we have reached the conclusion that involving employees in the decision making process is an important factor for the survival and progress of SMEs.

  20. CASH-FLOW SENSITIVITY TO PAYMENTS FOR MATERIAL RESSOURCES

    Directory of Open Access Journals (Sweden)

    Lavinia Elena BRÎNDESCU OLARIU

    2014-12-01

    Full Text Available The financing decision is taken based on the expectations concerning the future cash-flows generated in the operating activity, which should provide coverage for the debt service and allow for an increase of the shareholders’ wealth. Still, the future cash-flows are affected by risk, which makes the sensitivity analysis a very important part of the decision process. The current research sets to evaluate the sensitivity of the payment capacity to variations of the payments for raw materials and consumables. The study employs 391 forecasted yearly cash-flow statements collected from 50 companies together with detailed information concerning the hypotheses of the forecasts. The results of the study allow for the establishment of benchmarks for the payment capacity’s sensitivity, the determination of the mechanisms through which the variation of payments for raw materials and consumables impacts the payment capacity, as well as the identification of the possible causes of such a variation.

  1. Apprentissage en collaboration pour la cogestion des ressources ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Les prairies et les steppes de la Mongolie abritent actuellement quelque 35 millions de têtes de bétail et 180 000 familles de pasteurs. Les écosystèmes des prairies sont fragiles, très vulnérables à la dénudation des sols et lents à se rétablir, surtout à cause du climat froid et sec. Partout au pays, les pasteurs sont confrontés ...

  2. An excellence of service thanks to adequat supervision ressources

    CERN Multimedia

    Staff Association

    2012-01-01

    At the meeting of the Tripartite Employment Conditions Forum (TREF) of 30th May, HR Department presented some key statistical data concerning CERN staff and, more particularly, its evolution since 2001. The Member States delegates were in particular interested in various diversity issues, especially the distribution of age, seniority, and gender. As far as the distributions of nationalities of current staff and at recruitment are concerned no significant bias was observed, a result of efforts over the last years to ensure a more balanced situation for “under-represented” countries. The Staff Association stated it is very much concerned with the evolution of the number of staff members, which has been decreasing continuously during the last decade (in 2001 we were 2663 staff members; in 2011 only 2424 of which 2358.4 full-time equivalents and 2256 remunerated by CERN). At the same time the number of users (5512 in 2001, 10388 in 2011) has almost doubled (see Fig. 1). Fig. 1 On top ...

  3. Målstyring af og frihedsgrader til de menneskelige ressourcer

    DEFF Research Database (Denmark)

    Nielsen, Kjeld

    2010-01-01

    bevaring af arbejdspladser. I den voluntaristiske tilgang til ledelse af personale bevæger virksomhederne sig i en ”sociologisk dualisme” mellem hårde og bløde tilgange. Strukturerne på arbejdsmarkedet og kulturelle forhold i samspillet mellem samfund og virksomhed i det danske samfund betyder, at begge...

  4. Promouvoir la bonne gouvernance des ressources naturelles dans ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Il encouragera l'émergence et le renforcement du leadership féminin, la promotion des ... The main objective of this competitive research fund is to support applied ... The Science Granting Councils Initiative in sub-Saharan Africa wins Science ...

  5. Extraction d'association d'EIM à partir de dossiers patients : expérimentation avec les structures de patrons et les ontologies

    OpenAIRE

    Personeni , Gabin; Devignes , Marie-Dominique; Dumontier , Michel; Smaïl-Tabbone , Malika; Coulet , Adrien

    2016-01-01

    National audience; Les Dossiers Médicaux Electroniques (DME) constituent une ressource de grand intérêt pour étudier les Evènements Indésirables Médicamenteux (EIM). Nous proposons ici de fouiller les DME pour identifier des EIM fréquemment associés dans des sous-groupes de patients. Les EIM ayant des manifestations complexes, nous utilisons l'analyse formelle de concepts et ses structures de patrons, un cadre mathématique permettant la généralisation, en exploitant les connaissances du domai...

  6. M and S Resource Discovery and Access (Communication des ressources de M and S et acces a ces ressources)

    Science.gov (United States)

    2016-12-01

    document “ climate modeling results” and has established an associated metadata catalog. [10] Spain, France, and others are members of the Drug Disease...Implementation Guide. Version 1. [10] Guilyardi, E., et al. (2013) Documenting Climate Models and Their Simulations. Bull. Amer. Meteor. Soc., 94...PAYS-BAS Ministry of Defence ESTONIE Royal Netherlands Military Central Registry for EU & NATO Estonian National Defence College Academy Library

  7. Szilard-Chalmers Processes in Ammonium Dihydrogen Phosphate as Studied by Electrophoresis and Electron Spin Resonance Techniques; Processus Szilard-Chalmers dans le Phosphate d'Ammonium Biacide Etudies par ELectro- Phorese et Resonance de Spin Electronique; 0418 0417 0423 0427 0414 ; Procesos Szilard-Chalmers en el Fosfato Monoamonico Estudiados por Electroforesis y Resonancia del Spin Electronico

    Energy Technology Data Exchange (ETDEWEB)

    Fenger, J.; Nielsen, S. O. [Danish AEC Research Establishment, Riso (Denmark)

    1965-04-15

    'un cristal expose a des neutrons. En vue de caracteriser et d'identifier ces defauts par la resonance de spin electronique (RSE), les auteurs donnent les resultats d'une etude qu'ils ont faite, a l'aide d'une methode fondee sur l'electrophorese et la RSE, sur des monocristaux de phosphate d'ammonium biacide apres exposition aux neutrons dans une colonne thermique a des temperatures de -196 Degree-Sign C a 40 Degree-Sign C. Les spectres RSE ont ete obtenus a l'aide de monocristaux irradies de ND{sub 4}D{sub 2}PO{sub 4}. On a decouvert quatre systemes de raies. Trois de ces systemes, formant la partie exterieure du spectre, se reduisent a des doublets pour certaines orientations du cristal, ce qui laisse supposer un couplage hyperfin avec {sup 31}P. Rien ne prouve jusqu'a present qu'il existe un couplage avec {sup 32}P. La partie centrale du spectre a pu etre egalement obtenue sous l'effet d'une irradiation gamma pure. Un systeme de raies de la partie exterieure du spectre qui avait pour origine des atomes chauds de recul provenant de la reaction {sup 14}N(n, p){sup 14}C a ete attribue a des radicaux phosphites qui sont orientes de huit facons differentes dans le reseau cristallin. Les resultats du recuit thermique et du radiorecuit, etudies par electrophorese, font l'objet d'un bref examen critique. La constatation la plus interessante a ete le fait que ND{sub 4}D{sub 2}PO{sub 4} et NH{sub 4}H{sub 2}PO{sub 4} exposes aux neutrons a 4 Degree-Sign C, -78 Degree-Sign C et -196 Degree-Sign C different par la retention qui est d'environ 50% plus elevee pour ND{sub 4}D{sub 2}PO{sub 4} a ces trois temperatures. (author) [Spanish] Se poseen escasos datos directos sobre los efectos producidos en los fosfatos cristalinos por los atomos calientes de retroceso, resultantes de la reaccion nuclear {sup 31}p (n, {gamma}){sup 32}p, aunque se dispone de amplia informacion sobre el estado del {sup 32}P despues de la disolucion de los cristales irradiados con neutrones. Los autores procuran

  8. Hidrelétricas no Rio Madeira-RO: tensões sobre o uso do território e dos recursos naturais na Amazônia Hydroélectriques dans la rivière Madeira-RO: les tensions sur l´usage du territoire et des les ressources naturelles d’Amazonie Hydroelectric at the Madeira River: tensions about the territory using and the natural resources in the Amazon

    Directory of Open Access Journals (Sweden)

    Leonardo José Cordeiro Santos

    2012-06-01

    Full Text Available A construção das usinas hidrelétricas (Jirau e Santo Antônio, iniciadas em 2008, no Rio Madeira, município de Porto Velho-RO, confere à parte da Amazônia Sul Ocidental Rondoniense, uma (revalorização diante do contexto nacional e internacional devido ao potencial energético e ainda por compor parte de complexos para circulação e energia Sul-Americana. A materialização da obra incide sobre a intensificação dos conflitos sobre o uso do território e de seus recursos, fato comprovado a partir das análises feitas sobre as escalas de atuação dos atores e as estratégias na utilização dos recursos naturais na área de estudo. Os resultados ratificam que na Amazônia Rondoniense as políticas de infraestrutura estabelecidas são resultantes de interesses externos a região e, quando implantadas, desestruturam a lógica de organização local, elevando as tensões ambientais e sociais.La construction des usines hydroélectriques (Jirau et Santo Antônio, commencée en 2008, sur le Rio Madeira, dans le município Porto Velho-RO, (revalorise la partie d’ Amazonie Sud Occidentale dú Rondônia en raison du potentiel énérfetique qu’elle gènére et son inscription dans le réseau d’alimentation électrique de l’Amérique du Sud. Mais l´rélisation des ouvrages intensifie les conflits d’utilisation du territoire et de ses ressources, comme le conferment les analyses produites par cette recherché sur les échelles d’intervention des acteurs et les estratégies d’utilisation des ressources naturelles dans la zone d’éstude. Les résultats montrent que dans l’Amazonie du Rondônia, les politiques d’infrastructure telles qu’elles sont conçues resultant d’intérêts externes à la région et, lorsqu’wlles sont implantées, déstructurent les logiques d’organisation locale et provoquent des tensions environnementales et sociales.The building of the hydroelectric plants (Jirau and Santo Antônio, which started

  9. Du poids des contraintes au partage concerté des ressources : quelques témoignages des acteurs centraux de la conciliation travail-famille From the burden of constraints to the sharing of resources: Some statements by the central actors in work-family balance Del peso de las exigencias a compartir recursos de manera concertada : Algunos testimonios de los actores centrales de la conciliación trabajo-familia

    Directory of Open Access Journals (Sweden)

    Lise Chrétien

    2006-10-01

    Full Text Available Partant du constat que les parents-travailleurs d’aujourd’hui ont de plus en plus de difficulté à assumer les responsabilités professionnelles et familiales qui leur incombent, le présent article aborde, par le biais d’une recherche qualitative menée auprès de 30 parents-travailleurs : 1 les situations-problèmes vécues par les parents-travailleurs en matière de conciliation travail-famille, 2 les effets ressentis par les parents-travailleurs face à ces situations-problèmes, 3 les attentes des parents-travailleurs en regard des acteurs des sphères familiale, professionnelle, collective et gouvernementale pour en arriver à surmonter ces situations-problèmes. Les témoignages des participant(es y sont analysés à partir d’une approche holistique de la conciliation travail-famille, de type systémique, qui met en jeu la dialectique contraintes-ressources.Starting with the observation that today’s working parents are having increasing difficulty assuming their work and family responsibilities, this paper addresses, through the results of a qualitative study on 30 working parents: 1 the problem situations experienced by working parents regarding the work-family balance, 2 the effects experienced by working parents in dealing with these situations, 3 the expectations of working parents regarding other actors from family, work, community and governmental spheres in overcoming these problem situations. The participants’ statements are analyzed within a holistic work-family balance approach, based on a systemic model that involves a constraint-resource dialectic.Esta reflexión colectiva sobre la primera investigación « de terreno » (hace 40 años ! de los ergónomos del Conservatoire Constatando que los padres y madres que trabajan hoy en día tienen cada vez más dificultad a asumir las responsabilidades profesionales y familiares que les incumben, este estudio aborda a través de una investigación cualitativa llevada

  10. Air pollution and hospital admissions for cardiovascular disease in Tucson; Pollution de l'air et admissions hospitalieres pour maladies cardiovasculaires a Tucson

    Energy Technology Data Exchange (ETDEWEB)

    Schwartz, J.

    2001-01-01

    This study aims to show the impact of air pollutants on the hospital admissions for cardiovascular disease, in particular, the difference between the effects of the suspended particles and the effects of the sulfur dioxide. (A.L.B.)

  11. Diversification des ressources du réseau d’eau non potable parisien : contribution à une gestion durable des ressources en eau

    OpenAIRE

    Trinh , Bich-Thuy

    2017-01-01

    At the scale of a city, a sustainable water management raises questions about the links between uses and resources: what water quality is needed for what purpose? The Parisian context is a favourable ground for conducting such type of reflection thanks to the existence of a non-potable water network (RENP) dating from the late nineteenth century. The network is currently supplied by summarily filtrated water from the Seine river (20%) and the canal de l’Ourcql (80%). It is mainly used for mun...

  12. Electronic Warfare Test and Evaluation (Essai et evaluation en matiere de guerre electronique)

    Science.gov (United States)

    2012-12-01

    temperature measurements in a beam dump , converting it into a calorimeter. T&E OF EA SYSTEMS 3 - 40 RTO-AG-300-V28 Common laboratory and...simulation. Aircraft and other services • Cooling, hydraulics , pressurised air, ground power for aircraft; • Fire suppression, control room, CCTV...instrumentation, two man-rated hoists , a turntable, interconnecting networks, a test control room, presentation rooms, and office space, and a small

  13. Electronic de-multipliers II (ring-shape systems); Demultiplieurs electroniques II (systeme en anneau)

    Energy Technology Data Exchange (ETDEWEB)

    Raievski, V

    1948-09-01

    This report describes a new type of ring-shape fast electronic counter (de-multiplier) with a resolution capacity equivalent to the one made by Regener (Rev. of Scientific Instruments USA 1946, 17, 180-89) but requiring two-times less electronic valves. This report follows the general description of electronic de-multipliers made by J. Ailloud (CEA--001). The ring comprises 5 flip-flop circuits with two valves each. The different elements of the ring are calculated with enough details to allow the transfer of this calculation to different valve types. (J.S.)

  14. Conception et Réalisation d'une Toupie Electronique Pour la ...

    African Journals Online (AJOL)

    Verification of exposure time with Spinning Manual takes place on a single phase generator X-rays; the spinning top is for Motorized generators powered polyphase. In addition to these two restrictions are other disadvantages such as the timing of irradiation with the speed of rotation of the Spinning-Top or the need for ...

  15. International symposium on Electron-magnetic fields in mechatronics, electrical and electronique engineering

    CERN Document Server

    Krawczyk, Andrzej; Dolezel, Ivo

    2008-01-01

    Includes contributions on electromagnetic fields in electrical engineering which intends at joining theory and practice. This book helps the world-wide electromagnetic community, both academic and engineering, in understanding electromagnetism itself and its application to technical problems.

  16. Electromagnetic compatibility design and cabling system rules; Regles de conception et de cablage des systemes electroniques

    Energy Technology Data Exchange (ETDEWEB)

    Raimbourg, J.

    2009-07-01

    This report is devoted to establish EMC (Electromagnetic Compatibility) design and cabling system rules. It is intended for hardware designers in charge of designing electronic maps or integrating existing materials into a comprehensive system. It is a practical guide. The rules described in this document do not require enhanced knowledge of advanced mathematical or physical concepts. The key point is to understand phenomena with a pragmatic approach to highlight the design and protection rules. (author)

  17. Project for an analogue divider using electronic counting; Projet de diviseur analogique par comptage electronique

    Energy Technology Data Exchange (ETDEWEB)

    Novat, J [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1964-07-01

    The apparatus which has been developed is designed to give the reciprocal of a number between 10{sup 3} and 10{sup 7}. In practice this number can be the pulse count provided during a given time by a detector of the BF{sub 3} type during a criticality experiment. The apparatus is made up of two parts: one provides, by means of relays, a voltage proportional to the reciprocal required, the other is a numeric voltmeter measuring this voltage between 0.1 and 1 volt. The relative error of the result is under 5 per cent. (author) [French] L'appareillage etudie et realise, est destine a fournir l'inverse d'un nombre compris entre 10{sup 3} et 10{sup 7}. En pratique ce nombre est le taux d'impulsions delivrees pendant un temps donne, par un detecteur du type BF{sub 3}, au cours d'une manipulation de criticalite. L'appareillage est compose de deux parties: l'une fournit a l'aide de relais une tension proportionnelle a l'inverse cherche, l'autre est un voltmetre numerique mesurant cette tension comprise entre 0,1 et 1 Volt, L'erreur relative sur le resultat est inferieure a 5%. (auteur)

  18. Accès aux ressources internationales aux fins de la lutte antitabac ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Canada-Latin America and Caribbean Zika Virus Research Program. A new funding opportunity on Zika virus is responding to the virus outbreak and the health threat it represents for the affected populations in the hardest hit countries in Latin America and the... View moreCanada-Latin America and Caribbean Zika Virus ...

  19. NATO Human Resources (Manpower) Management (Gestion des ressources humaines (effectifs) de l’OTAN)

    Science.gov (United States)

    2012-02-01

    they need for particular jobs or career paths Gather labour market intelligence coherently and consistently quantify the skill requirements of the...machines, tools, and equipment. Similarly, labour market information defined by industry or occupation is also provided here. This domain is...150 Fax: [49] (0) 228 12 52 16 D-53123 Bonn e-mail: RalflJung@bmvg.bund400.de NORWAY /NORVEGE OSTBYE, Mr. P.R. Head of Section for

  20. Gestion des conflits de partage de ressources dans un environnement logiciel embarqué ouvert

    OpenAIRE

    Attouchi, Koutheir

    2014-01-01

    Our homes are becoming smart thanks to the numerous devices, sensors and actuators available in it, providing services, e.g., entertainment, home security, energy efficiency and health care. Various service providers want to take advantage of the smart home opportunity by rapidly developing services to be hosted by an embedded smart home gateway. The gateway is open to applications developed by untrusted service providers, controlling numerous devices, and possibly containing bugs or maliciou...

  1. Variabilité climatique et son incidence sur les ressources en eaux ...

    African Journals Online (AJOL)

    Climate change and climate variability studies are of great importance for water resources and management and planning in this paper, we put our attention on the impact of these ... Nicholson's and Maillet's method allow to put in evidence the climate variability with a random succession of periods of excess and deficits.

  2. Manuel et site Web de ressources sur l'élaboration d'une constitution

    International Development Research Centre (IDRC) Digital Library (Canada)

    élaboration d'une constitution est devenue un élément essentiel dans le cheminement vers la paix et la démocratie, en période de conflit, après un conflit et dans un contexte de transition. Les constitutions servent à régir les relations entre un État et ...

  3. ÉTUDE DE CAS — Équateur : Apprendre à partager les ressources ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    15 déc. 2010 ... Les forêts des nuages qui jouxtent le páramo font partie des écosystèmes andins les plus rares — 60 % des diverses espèces végétales qui y vivent ne se .... Cette action concertée, et la prise de conscience par les autorités d'Espejo des répercussions de leurs gestes, ont permis dès lors de surveiller plus ...

  4. Climate disturbance and water resources; Dereglement climatique et ressources en eau

    Energy Technology Data Exchange (ETDEWEB)

    Nguyen, Tien-Duc

    2012-01-01

    The worldwide multiplication of extreme climatic events (heat waves, dryness, floods, storms..) and their impact on the precious water resources raises the question of climate change: is it a reality, are the consequences already visible, should we urgently take care of it, and if so who actually takes care of it and how? This books makes a comprehensive overview of our knowledge about these questions, in a relevant and pedagogical way. Solutions to contain the climate boom risk exist and are based on the shared solidarity and responsibility. They require a strong involvement of the entire international community and their implementation has to run counter to the traditional opposition between developed and developing countries. However, the present day economic crisis is often used as a pretext for not doing anything. (J.S.)

  5. Assessment and evaluation of geothermal potential in Switzerland; Atlas des ressources geothermiques suisses

    Energy Technology Data Exchange (ETDEWEB)

    Andenmatten-Berthoud, N. [Geowatt AG, Zuerich (Switzerland); Kohl, T. [Eidgenossische Technische Hochschule (ETH), Institut de Geophysique, Zuerich (Switzerland)

    2003-07-01

    This report for the Swiss Federal Office of Energy presents the first part of a project that aims at assessing the geothermal energy potential of Switzerland's underground. Due to the presence of the Alps the Swiss underground is highly heterogeneous with numerous geologic faults. Geothermal energy assessment has to be carried out region after region. The first steps consisted in collecting existing geological and hydrogeological data and finding out the best appropriate methodology. Analysis was restricted to the Northwest of Switzerland (Basle-Zurich area), which has a dense population - an important factor for future applications - and is better known than others, thanks to previous studies performed in conjunction with site pre-selection for future radioactive waste disposal facilities. In this area, sandstones and limestones are found on the crystalline bottom rock. Mathematical models and computer codes were developed for interpolation and extrapolation of local and regional data. Three dimensional finite-element techniques were used. The results are presented in diagrams and maps.

  6. Ressources humaines en matière de santé dans la Chine rurale ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Six world-class research teams to investigate overcoming therapeutic resistance in high fatality cancers. The world-class research teams will direct their focus towards new frontiers in cancer research. View moreSix world-class research teams to investigate overcoming therapeutic resistance in high fatality cancers ...

  7. Gestion des forêts et des ressources hydriques pour l'atténuation ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Les collines de la région népalaise de l'Himalaya abritent une partie importante de la population du pays. Or, il s'agit d'une région particulièrement vulnérable aux répercussions des changements climatiques. Les faibles précipitations et les températures élevées qui ont marqué l'hiver 2008-2009 ont été à l'origine de la ...

  8. Comprendre les besoins en ressources végétales des populations ...

    African Journals Online (AJOL)

    Cossi Aristide Adomou, Hospice Gbèwonmèdéa Dassou, Gbèdomèdji Hurgues Aristide Houenon, Amour Alladayè, Hounnankpon Yedomonhan ... English Title: Understanding the plant resource needs of the surrounding populations for sustainable management of the Bahazoun forest in South Benin (West Africa).

  9. Renforcement de la capacité des ressources humaines dans le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    -Quelles sont les compétences et les capacités nécessaires pour gérer efficacement le cycle de vie du secteur extractif (exploration, exploitation, gestion, fermeture ... Women in the developing world continue to face obstacles that limit their ability to establish careers and become leaders in the fields of science, technology, ...

  10. Modèles formels du calcul quantique : ressources, machines abstraites et calcul par mesure

    OpenAIRE

    Perdrix , Simon

    2006-01-01

    Prix de thèse INP Grenoble 2008; The study of foundational structures of quantum information processing is a key issue to gain a deeper insight into what quantum computation is in general, its scope and limits. It also contributes to the physical realisation while minimising the resources of quantum computing. The resources consist of the space and times as well as the size of the operations and the amount of entanglement. This thesis contributes in several ways to minimise resources for rec...

  11. What is the sun's real potential?; Quelles sont les vraies ressources du soleil?

    Energy Technology Data Exchange (ETDEWEB)

    Joliot, P

    2009-07-01

    The sun has colossal energy potential, yet it is barely exploited. It radiates 10,000 times more energy than man now uses. Plants only recover one thousandth of this immense energy source. A closer look at the potential of processes for using solar energy, from photovoltaics to biofuels and biomass to the 'promise' of artificial photosynthesis The sun represents an inexhaustible source of energy. It is the well from which most of the energy sources available on the earth's surface spring, excepting nuclear and geothermal energy. Among the methods capable of recovering solar energy directly, three of them are currently in use: - Producing hot water with solar collectors; - High-temperature thermal power plants (1,000 deg.C or more); - Photovoltaics. Photovoltaic electricity already represents a significant source of energy in areas with low population density. Generating such power can also help meet the basic needs of poor countries. The last two methods nevertheless require a means for storing the energy produced, a function provided by the hot water tank in the first method. What about photosynthetic reactions that convert solar energy into chemical energy? Photosynthesis not only synthesizes organic products, it also recycles carbon dioxide and regenerates oxygen, all of which are vital to maintaining life on earth. We currently expect to produce renewable energy - mainly biofuels - by converting biomass produced by photosynthesis. Plants generally store less than 1% of the sun's energy in their organic matter. This feeble energy balance can become negative when the energy spent for sowing, harvesting and processing is taken into account, especially if only a fraction of the organic matter is actually collected, as in the case of corn or rapeseed oil. The substantial amount of land and water needed to produce large quantities of biofuels would put too much strain on food crops, especially in light of the large and ever growing numbers of people suffering from malnutrition in the world. The only reasonable energy policy would therefore involve improving the collection and use of wood and food crop waste, which already account for 10% of the world's energy production. Last in line comes artificial photosynthesis, which is often described as an energy source that competes with photovoltaic energy. The term 'artificial photosynthesis' is devoid of any technical meaning. What it really comes down to is communication. However, it does seem possible to imitate certain components of the photosynthetic apparatus, such as those involved in decomposing water into hydrogen and oxygen.

  12. ÉTUDE DE CAS — Bhoutan : Le partage des ressources dans les ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    15 déc. 2010 ... Water Demand Management for Social Justice ... Women play larger role in Latin America's commercial urban waste management ... the management of solid waste in Latin America, according to research supported by IDRC.

  13. Le sans fil, un outil de gestion des ressources au Mozambique ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    3 févr. 2011 ... ... nouvelle réserve naturelle de la province septentrionale de Niassa. Heureusement, son téléphone sans fil à haute fréquence lui a permis d'appeler sa station de base à l'aide. Malgré la distance, ses collègues ont pu lui porter secours en demandant à une pourvoirie d'envoyer un petit avion le cueillir.

  14. Sylvain Dufour, vice-président, Ressources, et chef de la direction ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Chantal Taylor

    12 mai 2013 ... Trimestre 3 du 6 au 13 octobre 2013. Orlando, États-Unis. Conférence. 1 843,35. 913,73. -. 2 757,08. Trimestre 4 du 16 au 26 janvier 2014. Nairobi, Kenya. Visite au BRAS. 12 443,88. 3 546,66. 15 990,54 le 2 février 2014. Ottawa, Canada. Renouvellement de passeport. Total de l'exercice 2013-2014.

  15. Élaboration de politiques nationales sur l'accès aux ressources ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Ce projet amènera des équipes de recherche expérimentées en provenance de ... des articles scientifiques, un livre et des documents de formation en anglais et ... Centre international de recherche agricole dans les zones arides ... de coopération scientifique et technologique en appui aux projets de recherche conjoints.

  16. TempoWordNet : une ressource lexicale pour l'extraction d'information temporelle

    OpenAIRE

    Hasanuzzaman , Mohammed

    2016-01-01

    The ability to capture the time information conveyed in natural language, where that information is expressed either explicitly, or implicitly, or connotative, is essential to many natural language processing applications such as information retrieval, question answering, automatic summarization, targeted marketing, loan repayment forecasting, and understanding economic patterns. Associating word senses with temporal orientation to grasp the temporal information in language is relatively stra...

  17. Comprendre les besoins en ressources végétales des populations ...

    African Journals Online (AJOL)

    traitement de l'asthme à Kisangani et ses environs (Province Orientale, R. D.. Congo). Annales des. Sciences,. Université Officielle de Bukavu, 1(1):. 63-68. Maregesi S, Ngassapa O, Pieters L, Vlietinck. A. 2007. Ethnopharmacological survey of the Bunda district, Tanzania: Plants used to treat infectious diseases. Journal.

  18. Modèles de gestion des ressources forestières du massif ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Ingénieurs. Institution Country. Maroc. Institution Website. http://www.enfi.ac.ma. Project Leader. Dr. Mohamed Khemici. Institution. Institut national de la recherche forestière. Institution Country. Algérie. Project Leader. Dr. Abdelhamid Khaldi ...

  19. 17. Meeting municipal waste Magdeburg. Residual waste - recycling - resource; 17. Tagung Siedlungsabfallwirtschaft Magdeburg. Restabfall - Recycling - Ressource

    Energy Technology Data Exchange (ETDEWEB)

    Haase, Hartwig (ed.)

    2012-11-01

    Within the 17th meeting Waste Management at Residential Areas from 12th o 13th September, 2012 in Magdeburg (Federal Republic of Germany), the following lectures were held: (1) Opening Session - Waste management in Saxony-Anhalt (O. Aeikens); (2) World with future - the eco-social perspective (F.J. Radermacher); (3) Global commodity markets - rare earths and their recycling (I. Fahimi); (4) The further development of nearhousehold capture of recyclable materials (J. Seitel); (5) On the future of the disposal management (J. Balg); (6) Options for action for the future of the municipal waste management (A. Gosten); (7) Current models of the capture of recyclable materials in Germany (M. Kerkhoff); (8) The recycling bin as a pilot test in Hanover (R. Middendorf); (9) Position of BellandVision on the implementation of a unified recycling bin (J. Soelling); (10) What will change with the new Recycle Economy Law according to the material flows and waste treatment capacities? (H. Alwast); (11) Waste management plan Saxony-Anhalt - Current developments (S. Hagel); (12) Wastes from the thermal waste treatment - Risk potential and disposal (G.-R. Behr); (13) Landfill Mining - Contribution of the waste management to the securing of resources (K. Fricke); (14) Logistic process design and system design in the transport of wastes in developing countries using Serbia as an example (Z. Jovanovic); (15) Example of good practices in the subsequent use of landfills - Solar park Cracauer Anger (M. Harnack); (16) Ecoloop - energy efficient gasification in the limestone moving-bed (R. Moeller); (17) Utilization of waste and biomass as a resource? Only by means of an intelligent logistics. (S. Trojahn); (18) Renewable energy resources - Experiences of a network provider (J. Kempmann).

  20. Partenaire d'affaires en ressources humaines (h/f) | CRDI - Centre ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    à-d. des solutions de recrutement et de dotation) au sein du portefeuille de clients ... à la promotion et à la mise en oeuvre de la stratégie de gestion des talents en ... les politiques et lignes directrices ainsi que les valeurs de dotation et les lois ...

  1. La Contextualisation Des Banques de Ressources: Barrières et Clés

    Directory of Open Access Journals (Sweden)

    Aude Dufresne

    2002-10-01

    Full Text Available When developing learning resource banks for telearning, it is important to recognize known barriers to the re-use of learning objects and some possible solutions. First, in order that the resources be reused, they must have been created in a modular fashion, separating the resources from their intended context, storing separately the documents and their use in scenarios, or in the case of executable code in autonomous segments. Next, in order to promote the gradual exploration, understanding, evaluation and choice of learning objects, it is important to link the resources not only with metadata, but also explicit documentation on the theoretical and practical aspects of their use, as well as any relevant evaluation material. Finally, if we really want these resource banks to hold this rich ancillary information, we need to build tools that support this contextualization and the activities of all the actors in the telelearning environment from conception, through development and use.

  2. Geothermal Resources in China Les ressources géothermiques de la Chine

    OpenAIRE

    An K. S.; Huang S. Y.

    2006-01-01

    The present paper deals mainly with the distribution features, briefly describes the geology in the three geothermal fields of different types in Beijing, Yangbajing of Xizang (Tibet), and Dengwu of Guangdong, and finally gives on account of the development and utilization of geothermal resources. Up to now, more, than 2,500 geothermal water points (including hot springs, hot-water wells, and hot water in mines) have been found. Four major geothermal zones and three basic types of geothermal ...

  3. Ressources linguistiques et système de traduction en malais ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Le CRDI lance un nouveau projet dans la région de l'ANASE. L'honorable Chrystia Freeland, ministre du Commerce international, a annoncé le lancement d'un nouveau projet financé par le Centre de recherches pour le développement international (CRDI). Voir davantageLe CRDI lance un nouveau projet dans la région ...

  4. Cogestion des ressources naturelles en dépit de différences ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Si le projet proposé vise les collectivités Yshiro du Paraguay, un volet sera mené au Labrador en collaboration avec la nation innue et le gouvernement des Inuits du Nunatsiavut. Les trois cas combinés permettront de généraliser et de faire passer à grande échelle les résultats de la recherche sous forme de techniques et ...

  5. Gestion des ressources naturelles pour une sécurité alimentaire ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Au Sahel, le déficit de la production agricole et pastorale, combiné à la hausse générale des prix des denrées, ont augmenté l'insécurité alimentaire. Pour garantir leur sécurité alimentaire, les populations rurales utilisent des techniques de production agricole visant à maximiser leur production sans nécessairement se ...

  6. 118 Variabilité climatique et son incidence sur les ressources en ...

    African Journals Online (AJOL)

    MARTINE

    particulièrement fortes et touchent de nombreux secteurs d'activité. Le changement ... économique était basé sur l'agriculture est très sensible au contexte climatique [8,9]. ..... rupture. 3-2-6 Calcul du coefficient de tarissement : loi de Maillet.

  7. ÉTUDE DE CAS — Bhoutan : Le partage des ressources dans les ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    15 déc. 2010 ... Au début, tout s'est bien passé. Les deux groupes ont décidé d'établir une zone forestière communautaire sur les terres dégradées à proximité des deux villages. L'érosion du sol dans la zone choisie était très sévère et le ruissellement avait creusé deux larges ravines. L'objectif du projet consistait à créer ...

  8. Les huiles de poissons, une ressource à protéger

    Directory of Open Access Journals (Sweden)

    Lozachmeur Stéphane

    2008-07-01

    Full Text Available Each year more than 80 millions of tons of fish are caught in seas and oceans all over the world. 1/3 of the fish are used for the manufacturing of fish oils. Omega-3 from marine sources knows a great success on different markets (food, cosmetics, OTC… but the natural resources of fish are going to decrease: that would restrict the supplying sources in the future. We need to find other sources: research has been intensified these last years to evaluate consequences of the partial or total replacement of fish oils by vegetable oils. But the problem is the fatty acids content which is not the same. The replacement of fish oils by vegetable oils induces a diminution of omega-3 fatty acids content, which is the characteristic of fish oils (EPA & DHA. Other alternatives to fish oils: marine resources such as micro-algae, genetic manipulation (phytoplankton; reusing of co-products (fish skin, eggs….

  9. Ressources libres et qualité du téléenseignement en Asie | CRDI ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    La recherche sera menée par un réseau réunissant des universités, des organismes de formation et des collectivités d'apprentissage rurales de onze pays, certains ayant une expérience du téléenseignement (en Indonésie, au Japon, en Malaisie, aux Philippines et au Pakistan) et d'autres qui sont novices dans le ...

  10. La gestion des ressources naturelles dans la commune de Hong Ha ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    approvisionnement utilisée par l'armée nord-vietnamienne dans les années 1960 et 1970, la commune de Hong Ha — qui .... J'ai remboursé le prêt et utilisé les profits pour acheter de la nourriture et envoyer mes enfants à l'école. ».

  11. Gestion des forêts et des ressources hydriques pour l'atténuation ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Rapports. Web of resilience : cross-scale implications of forest and water management for adaptation-mitigation and food security in the Nepal Himalayas ... Le CRDI investit dans des solutions locales aux problèmes auxquels l'Inde est confrontée, comme le stress thermique, la gestion de l'eau et les migrations liées aux ...

  12. Le renforcement des capacités en mobilisation de ressources au CRDI

    International Development Research Centre (IDRC) Digital Library (Canada)

    pwust

    grande diversité de sources publiques et privées aux échelles locale, régionale et ..... du Nord : Les activités de RCMR n'ont été entreprises qu'en 2006, après avoir ...... Organizational Assessment: A Framework for Improving Performance,.

  13. Russian Arctic Petroleum Resources; Ressources petrolieres de l'Arctique russe

    Energy Technology Data Exchange (ETDEWEB)

    Zolotukhin, A.; Gavrilov, V. [Gubkin Russian State University of Oil and Gas, GSP-1, Leninsky prospekt, 65, 119991, Moscow - (Russian Federation)

    2011-07-01

    The Arctic continental shelf is believed to be the area with the highest unexplored potential for oil and gas as well as for unconventional hydrocarbon resources such as gas hydrates. Despite a common view that the Arctic has plentiful of hydrocarbon resources, there are ongoing debates regarding the potential of this region as a future energy supply base. Driving forces for such discussions are geopolitics, environmental concern, assessment and delineation of Arctic resources, technology available for their successful development and the market demand for energy supply. The Russian part is recognized to be the largest among oil and gas resources owned by Arctic nations. However, scarce information and available geological data create uncertainty regarding a future role of the Russian Arctic as main base of energy supply in the second part of the 21. century. A further uncertainty is the pace at which production from northern areas including the Arctic will be brought on stream - either because of national policy, infrastructure development or investment by the state and the oil companies. These areas embrace those where development has already been started (Offshore Sakhalin, northern Timan Pechora) and those awaiting future involvement, like Barents and Pechora seas, East Siberia, Yamal, Kara Sea and Kamchatka. Offshore production levels are likely to be very important to Russia in mid and long terms, especially as most (if not all) production will go for export and, in the process, open doors to new markets. In this way, offshore production will introduce a new and very significant component to Russia's export strategy. However, active involvement of the Russian Arctic resources in the global energy supply process needs a detailed analysis and clear understanding of the market potential for Russian gas and oil (required volumes, time frame, transportations routes) and requires close attention of the government to the most important issues that should be in place, like national standards and guidelines for Arctic resources development, stable, transparent and predictable law as a necessary precondition for massive investments in exploration and production and, not least, active involvement of foreign companies in development of Arctic resources that could bring along with investments an indispensable competence and experience, available technology and Health, Safety and Environment (HSE) principles. Development of oil and gas fields in the arctic seas located few hundreds miles from shore is according to expert opinion the most challenging project in the world. Without international cooperation, coordination of all activities and use of modern and proven technologies for production of hydrocarbons, their transport, efficient safety and environmental protection tools the realization of such a project would be questionable. (authors)

  14. La voie vers l'harmonie : savoir partager les ressources | CRDI ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    26 janv. 2011 ... Au Pérou, institutions publiques, entreprises privées, porteurs, touristes et même l'UNESCO forment un tissu complexe d'intérêts divers et se disputent sur la façon de gérer le site fragile qu'est la citadelle du Machu Picchu. À Cochabamba, en Bolivie, la gestion de l'approvisionnement en eau a fait l'objet ...

  15. Coal: resources, reserves and production - Panorama 2008; Charbon: ressources, reserves et production - Panorama 2008

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2008-07-01

    For the French, whose last coal mine closed in 2004, the 'comeback' of coal as a political issue may seem a bit surprising. Even if coal is still used in domestic industry and to produce electricity, it is many years since it was used as the primary energy source for electricity production. This situation, specific to France and certain European countries, is not at all typical of the world situation: in the face of surging energy demand, coal - whose reserves have been estimated by the World Energy Council to cover 145 years of consumption at the current rate - seems to be an energy of the future and an alternative to oil, natural gas and nuclear power for the production of electricity.

  16. La conservation des ressources phytogéné-tiques : une préoccupation internationale

    Directory of Open Access Journals (Sweden)

    Thomas Gass

    1998-01-01

    Full Text Available Conservation of plant genetic resources: an international issue.This paper briefly reviews the activities of the organizations dealing with plant genetic resources conservation on the international level, with spécial référence to the European région. The initiatives of FAO within its Commission on Genetic Resources for Food and Agriculture are described, in particular the formulation of an International Understanding and its révision in connexion with the Convention on Biological Diversity, the realization of a Report on the State of the World's Plant Genetic Resources for Food and Agriculture and the drafting of a Global Plan of Action. The role of technical coordination played at the global level by IPGRI is also explained, with a brief outline of its objectives. Regarding coopération within the European région, the European Coopérative Programme on Plant Genetic Resources Networks, ECP/GR, covers the arec of crop plants while EUFORGEN deals with forest genetic resources. Information is given on the organization of these programs, both of which are co-ordinated by IPGRI, and on the dialog between the European Commission and co-ordinators on plant genetic resources of member States of the European Union

  17. Ressources libres et qualité du téléenseignement en Asie | IDRC ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    éducation, de telle sorte que de nombreux pays pourraient ne pas être en mesure d'atteindre les objectifs du Millénaire pour le développement en matière d'éducation d'ici à 2015; bon nombre de pays tentent de remédier à la situation grâce au ...

  18. Élaboration de politiques nationales sur l'accès aux ressources ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Action Oriented Research and Activities to Support Implementation of Access and Benefit Sharing Policies and Laws in Peru: Confronting Misuse and Misappropriation of Seeds, Genetic Resources and Traditional Knowledge. Download PDF. Reports. Fair access and benefit sharing of genetic resources: national policy ...

  19. Les Associations Pastorales et la Gestion des Ressources Naturelles : Tome 2: Niger

    NARCIS (Netherlands)

    H.A. Sidikou (Hamidou)

    1994-01-01

    textabstractLes politiques de développement pastoral en Afrique sahélienne et plus particulièrement au Niger , ont beaucoup évolué au cours des vingt dernières années. Elles ont également montré leurs limites et influencé sinon infléchi de ce fait la perception des organes de

  20. Production de biocarburants à partir de la ressource oléagineuse

    Directory of Open Access Journals (Sweden)

    Daudin Antoine

    2012-01-01

    Full Text Available Biofuels, which are produced from renewable vegetable sources are considered as a good solution to reduce the European dependence on fossil fuel sources, from a geostrategic and environmental point of view. Because of the high proportion of diesel vehicles in Europe, biodiesel still remains by far the most produced biofuel, far ahead of ethanol. Biodiesel is obtained by transesterification of vegetable oils with an alcohol, usually methanol to produce methyl esters. This paper aims to present the contribution of the French institute IFP Energies nouvelles to this issue, through the development of two processes for biodiesel production by means of homogeneous or heterogeneous catalysis. More recent developments have focused on hydrotreating vegetable oils and are also detailed in this paper. Fuels from this latest technology are drop-in fuels allowing higher incorporation rates and offering excellent qualities for diesel engines and potentially for incorporation in Jet fuel.

  1. Créer des ressources audio pour le cours de FLE

    Directory of Open Access Journals (Sweden)

    Florence Gérard Lojacono

    2010-01-01

    Full Text Available These last ten years, web applicationshave gained ascendency over the consumersociety as shown by the success of iTunesand the increase of podcasting. The academicworld, particularly in the field oflanguage teaching, could take advantage ofthis massive use of audio files. The creationand the diffusion of customized ad hocaudio files and the broadcast of these resourcesthrough educational podcasts addressthe upcoming challenges of a knowledgebased society. Teaching and learningwith audio files also meet the recommendationsof the European Higher EducationArea (EHEA. This paper will provide languageteachers, especially French teachers,with the tools to create, edit, upload andplay their own audio files. No specific computerskills are required.

  2. Approche systémique du processus de gestion des ressources humaines

    Directory of Open Access Journals (Sweden)

    Cesar Nieto Licht

    2013-08-01

    Full Text Available Rev.esc.adm.neg Mediante la comprensión de la teoría sistémica, su evolución y sus aplicaciones se plantearán los retos generales y específicos que afrontan actualmente los profesionales de Gestión Humana para diseñar y desarrollar sus procesos de manera sistémica, generando valor para la organización y aportando significativamente al desarrollo de la empresa y de los seres humanos que la conforman. Por lo tanto, este artículo presentará una exploración por las herramientas de la era de la máquina, su impacto en el proceso de pensamiento de los administradores, el significado de la era sistémica y sus aplicaciones e incidencias en el diseño de los procesos. Finalmente, se presentarán los retos específicos que los profesionales de Gestión Humana deben afrontar para intervenir sus procesos bajo un enfoque sistémico.

  3. Karst et ressources en eau au moyen Atlas nord-oriental

    OpenAIRE

    Taous, Ali; Tribak, Abdellatif; Obda, Khalid; Baena Escudero, Rafael; López Lara, Enrique Javier; Miranda Bonilla, Jose

    2009-01-01

    Le Moyen Atlas nord-oriental se caractérise par des paysages kartisques hérités et actuels très diversifiés. En fait, les roches carbonatées du Jurassique, bien représentées dans cette région montagneuse, ont subi une karstification ancienne, depuis la fin du Tertiaire et au cours du Quaternaire. Actuallement, la karstogenèse est encore active en raison des conditions géologiques, morphostructurales et bioclimatiques favorables: couches de roches carbonatées inclinées et plissées, climat médi...

  4. Accès des femmes à la terre et aux ressources naturelles dans les ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Realties of women facing multiple exclusion in accessing land and land-based resources in pastoralist and forest dwelling communities in Uganda. 50878. Papers. Access to land and land based resources among women in pastoralist and forest-dependent communities in East Africa. 50877. Reports. Access to land and ...

  5. Accès des femmes à la terre et aux ressources naturelles dans les ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Realties of women facing multiple exclusion in accessing land and land-based resources in pastoralist and forest dwelling communities in Uganda. Téléchargez le PDF. Documents. Access to land and land based resources among women in pastoralist and forest-dependent communities in East Africa. Téléchargez le PDF.

  6. The Political Economy of Land and Natural Ressource Investments in Africa

    DEFF Research Database (Denmark)

    Buur, Lars; Nystrand, Malin; Pedersen, Rasmus Hundsbæk

    Large-scale investments in natural resources (extractives as well as agriculture) can help transform African economies by accelerating economic growth, creating jobs and strengthening the links between local economies and the global economy more broadly. However, they often end up violating rights......, which in turn may lead to social protests and political instability. This Working Paper develops an analytical framework for analysing the implementation of large-scale investments in natural resources. It focuses on the triangular relations between investors, local populations and ruling elites...... to understand why some investments are implemented more successfully than others, it is necessary to grasp the politics behind an investment. The paper also explores the conditions under which investments can be implemented without violating the rights of local populations. The paper is based on a review...

  7. Electron cyclotron waves transmission: new approach for the characterization of electron distribution functions in Tokamak hot plasmas; La transmission d`ondes cyclotroniques electroniques: une approche nouvelle pour caracteriser les fonctions de distribution electronique des plasmas chauds de Tokamak

    Energy Technology Data Exchange (ETDEWEB)

    Michelot, Y

    1995-10-01

    Fast electrons are one of the basic ingredients of plasma operations in many existing thermonuclear fusion research devices. However, the understanding of fast electrons dynamics during creation and sustainment of the superthermal electrons tail is far for being satisfactory. For this reason, the Electron Cyclotron Transmission (ECT) diagnostic was implemented on Tore Supra tokamak. It consists on a microwave transmission system installed on a vertical chord crossing the plasma center and working in the frequency range 77-109 GHz. Variations of the wave amplitude during the propagation across the plasma may be due to refraction and resonant absorption. For the ECT, the most common manifestation of refraction is a reduction of the received power density with respect to the signal detected in vacuum, due to the spreading and deflection of the wave beam. Wave absorption is observed in the vicinity of the electron cyclotron harmonics and may be due both to thermal plasma and to superthermal electron tails. It has a characteristic frequency dependence due to the relativistic mass variation in the wave-electron resonance condition. This thesis presents the first measurements of: the extraordinary mode optical depth at the third harmonics, the electron temperature from the width of a cyclotron absorption line and the relaxation times of the electron distribution during lower hybrid current drive from the ordinary mode spectral superthermal absorption line at the first harmonic. (J.S.). 175 refs., 110 figs., 9 tabs., 3 annexes.

  8. Study of electronic heat transport in plasma through diagnosis based on modulated electron cyclotron heating; Etudes de transport de la chaleur electronique par injection modulee d'ondes a la frequence cyclotronique electronique

    Energy Technology Data Exchange (ETDEWEB)

    Clemencon, A.; Guivarch, C

    2003-07-01

    In order to make nuclear fusion energetically profitable, it is crucial to heat and confine the plasma efficiently. Studying the behavior of the heat diffusion coefficient is a key issue in this matter. The use of modulated electron cyclotron heating as a diagnostic has suggested the existence of a transport barrier under certain plasma conditions. We have determined the solution to the heat transport equation, for several heat diffusion coefficient profiles. By comparing the analytical solutions with experimental data; we are able to study the heat diffusion coefficient profile. Thus, in certain experiments, we can confirm that the heat diffusion coefficient switches from low to high values at the radius where the electron cyclotron heat deposition is made. (authors)

  9. Molecular and electronic structure of actinide hexa-cyanoferrates; Structure moleculaire et electronique des hexacyanoferrates d'actinides

    Energy Technology Data Exchange (ETDEWEB)

    Bonhoure, I

    2001-07-01

    The goal of this work is to improve our knowledge on the actinide-ligand bond properties. To this end, the hexacyanoferrate entities have been used as pre-organized ligand. We have synthesized, using mild chemistry, the following series of complexes: An{sup IV}[Fe{sup II}(CN){sub 6}].xH{sub 2}O (An = Th, U, Np, Pu); Am{sup III}[Fe{sup III}(CN){sub 6}].xH{sub 2}O; Pu {sup III}[Co{sup III}(CN){sub 6}].xH{sub 2}O and K(H?)An{sup III}[Fe{sup II}(CN){sub 6}].xH{sub 2}O (An = Pu, Am). The metal oxidation states have been obtained thanks to the {nu}{sub CN}, stretching vibration and to the actinide L{sub III} absorption edge studies. As Prussian Blue, the An{sup IV}[Fe{sup II}(CN){sub 6}].xH{sub 2}O (An = Np, Pu) are class II of Robin and Day compounds. X-ray Diffraction has shown besides that these complexes crystallize in the P6{sub 3}/m space group, as the isomorphic LaKFe(CN){sub 6}.4H{sub 2}O complex used as structural model. The EXAFS oscillations at the iron K edge and at the An L{sub III} edge allowed to determine the An-N, An-O, Fe-C and Fe-N distances. The display of the multiple scattering paths for both edges explains the actinide contribution absence at the iron edge, whereas the iron signature is present at the actinide edge. We have shown that the actinide coordination sphere in actinides hexa-cyanoferrates is comparable to the one of lanthanides. However, the actinides typical behavior towards the lanthanides is brought to the fore by the An{sup IV} versus Ln{sup III} ions presence in this family of complexes. Contrarily to the 4f electrons, the 5f electrons influence the electronic properties of the compounds of this family. However, the gap between the An-N and Ln-N distances towards the corresponding metals ionic radii do not show any covalence bond evolution between the actinide and lanthanide series. (author)

  10. Potentialities in electronics of new high critical temperature superconductors. Potentialites en electronique des nouveaux supraconducteurs a haute temperature critique

    Energy Technology Data Exchange (ETDEWEB)

    Hartemann, P [Thomson-CSF, 75 - Paris (FR)

    1989-09-01

    The main electronic applications of superconductors involve the signal processing, the electromagnetic wave detection and the magnetometry. Characteristics of devices based on conventional superconductors cooled by liquid helium are given and the changes induced by incorporating high-temperature superconductors are estimated. After a survey of new superconductor properties, the superconducting devices for analog or digital signal processing are reviewed. The gains predicted for high-temperature superconducting analog devices are considered in greater detail. Different sections deal with the infrared or (sub)millimeter wave detection. The most sensitive apparatuses for magnetic measurements are based on SQUIDs. Features of SQUIDs made of granular high-temperature superconducting material samples (grain boundaries behave as barriers of intrinsic junctions) are discussed.

  11. Analyse des proprietes electroniques de supraconducteurs a l'aide de la theorie de la fonctionnelle de la densite

    Science.gov (United States)

    Blackburn, Simon

    In this thesis, the electronic structure of different kinds of superconductors is explored with the density functional theory. A brief explanation of this theory is done in the introduction. The Hubbard model is also presented as it can be used to solve shortcomings of the theory in some materials such as cuprates. The blend of the two theories is the DFT+U which is used to describe materials with strongly correlated electrons. Afterward, a paper describing the electron-phonon coupling in the superconductor NbC1- xNx is presented. Results from this work show the role of the Fermi surface in the electron pairing mechanism leading to superconductivity. Based on these results, a model is developed explaining how the critical temperature is influenced by the change in frequency of the vibration modes. Then, quantum oscillation results based on a detailed analysis of Fermi surfaces, allowing a direct comparison with experimental data, are presented within two papers. The first one is about a material in the iron pnictide family, the LaFe2P2. Our calculations show that the Fermi surface of this material is different from the superconducting doped BaFe2As2 which explains why this material shows no sign of superconductivity. The second paper is about the heavy fermion system YbCoIn5. To do this, a new efficient method to calculate de Haas-van Alphen frequencies is developed. Finally, a paper on superconducting YBa2Cu3O6.5 is presented. Using DFT+U, the role of various magnetic orders on the Fermi surface are studied. The results allow a better understanding of the measured quantum oscillations in this material.

  12. Statistical treatment of data. Application to nuclear electronics; Traitement des informations en regime statistique. Applications a l'electronique nucleaire

    Energy Technology Data Exchange (ETDEWEB)

    Sicard, F [Commissariat a l' Energie Atomique, Saclay (France).Centre d' Etudes Nucleaires

    1960-07-01

    In this report the data of probability calculations are applied to the analyses of counting losses in experiments on chance events encountered in nuclear physics. The distribution of time intervals according to Poisson's law is studied and various applications of this are given: calculation of counting losses on a scale preceded by a fast de-multiplying circuit, decrease of the counting rate on the multichannel selectors, recording of statistical distribution phenomena on magnetic bands. (author) [French] Ce rapport applique les donnees du calcul des probabilites a l'analyse des pertes de comptage dans les experiences sur des evenements aleatoires rencontres en physique nucleaire. La distribution des intervalles de temps suivant une loi de Poisson est etudiee et differentes applications en sont donnees: calcul des pertes de comptage sur une echelle precedee d'un circuit de demultiplication rapide, diminution du taux de comptage sur les selecteurs multicanaux, enregistrement de phenomenes a distribution statistique sur bandes magnetiques. (auteur)

  13. Modeling of the response under radiation of electronic dosemeters; Modelisations de la reponse sous rayonnements de dosimetres electroniques

    Energy Technology Data Exchange (ETDEWEB)

    Menard, S. [Institut de Radioprotection et de Surete Nucleaire (IRSN), 92 - Fontenay-aux-Roses (France)

    2003-07-01

    The simulation with with calculation codes the interactions and the transport of primary and secondary radiations in the detectors allows to reduce the number of developed prototypes and the number of experiments under radiation. The simulation makes possible the determination of the response of the instrument for exposure configurations more extended that these ones of references radiations produced in laboratories. The M.C.N.P.X. allows to transport, over the photons, electrons and neutrons, the charged particles heavier than the electrons and to simulate the radiation - matter interactions for a certain number of particles. The present paper aims to present the interest of the use of the M.C.N.P.X. code in the study, research and evaluation phases of the instrumentation necessary to the dosimetry monitoring. To do that the presentation gives the results of the modeling of a prototype of a equivalent tissue proportional counter (C.P.E.T.) and of the C.R.A.M.A.L. ( radiation protection apparatus marketed by the Eurisys Mesures society). (N.C.)

  14. Electron microscope study of irradiated beryllium oxide; Etude au microscope electronique de l'oxyde de beryllium irradie

    Energy Technology Data Exchange (ETDEWEB)

    Bisson, A A [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1965-06-01

    The beryllium oxide is studied first by fractography, before and after irradiation, using sintered samples. The fractures are examined under different aspects. The higher density sintered samples, with transgranular fractures are the most interesting for a microscopic study. It is possible to mark the difference between the 'pores' left by the sintering process and the 'bubbles' of gases that can be produced by former thermal treatments. After irradiation, the grain boundaries are very much weakened. By annealing, it is possible to observe the evolution of the gases produced by the reaction (n, 2n) and (n. {alpha}) and gathered on the grain boundaries. The irradiated beryllium oxide is afterwards studied by transmission. For that, a simple method has been used: little chips of the crushed material are examined. Clusters of point defects produced by neutrons are thus detected in crystals irradiated at the three following doses: 6 x 10{sup 19}, 9 x 10{sup 19} and 2 x 10{sup 20} n{sub f} cm{sup -2} at a temperature below 100 deg. C. For the irradiation at 6 x 10{sup 19} n{sub f} cm{sup -2}, the defects are merely visible, but at 2 x l0{sup 20} n{sub f} cm{sup -2} the crystals an crowded with clusters and the Kikuchi lines have disappeared from the micro-diffraction diagrams. The evolution of the clusters into dislocation loops is studied by a series of annealings. The activation energy (0,37 eV) calculated from the annealing curves suggests that it must be interstitials that condense into dislocation loops. Samples irradiated at high temperatures (650, 900 and 1100 deg. C) are also studied. In those specimens the size of the loops is not the same as the equilibrium size obtained after out of pile annealing at the same temperature. Those former loops are more specifically studied and their Burgers vector is determined by micro-diffraction. (author) [French] L'oxyde de beryllium est d'abord etudie, par une methode fractographique, avant et apres irradiation, en utilisant des echantillons frittes. Les fractures sont examinees sous differents aspects. Ce sont les frittes les plus denses a fractures intragranulaires qui sont les plus interessants pour l'etude microscopique. Le 'pore' resultant du frittage est differencie de la 'bulle' qui peut se former au cours de traitements thermiques ulterieurs par suite de reactions donnant naissance a des gaz. Apres irradiation, la fragilisation intergranulaire est importante. Par recuit, on suit l'evolution des gaz, produits par les reactions (n. 2n) et (n, {alpha}), qui s'accumulent aux joints de grains. L oxyde de beryllium irradie est ensuite etudie par transmission. Pour cela, une methode simple a ete mise au point; elle consiste a examiner les eclats de cristaux broyes. Les amas de defauts ponctuels, formes par les neutrons, sont ainsi mis en evidence dans les cristaux irradies aux trois doses suivantes: 6.10{sup 19}, 9.10{sup 19} et 2.10{sup 20} n{sub r}.cm{sup -2} a une temperature inferieure a 100 deg. C. Pour l'irradiation a 6.10{sup 19} n{sub r}.cm{sup -2} les defauts sont a peine visibles mais a 2.10{sup 20} n{sub r}.cm{sup -2} les cristaux sont cribles d'amas alors que les lignes de Kikuchi ont disparu des diagrammes de microdiffraction. L'evolution des amas de defauts en boucles de dislocation est etudiee par des recuits successifs. L'energie d'activation de 0.37 eV, calculee a partir des courbes de recuits, incite a penser que ce sont les defauts interstitiels qui se condensent en boucles de dislocation. Des echantillons irradies a haute temperature sont egalement etudies (650, 900 et 1100 deg. C). Dans ceux-ci les boucles de dislocation atteignent un etat d'equilibre different de celui des precedentes. Ces dernieres boucles de dislocation sont etudiees plus specialement et leur vecteur de Burgers est determine par microdiffraction. (auteur)

  15. Wavelets as basis functions in electronic structure calculations; Les ondelettes comme fonction de base dans le calcul de structures electroniques

    Energy Technology Data Exchange (ETDEWEB)

    Chauvin, C

    2005-11-15

    This thesis is devoted to the definition and the implementation of a multi-resolution method to determine the fundamental state of a system composed of nuclei and electrons. In this work, we are interested in the Density Functional Theory (DFT), which allows to express the Hamiltonian operator with the electronic density only, by a Coulomb potential and a non-linear potential. This operator acts on orbitals, which are solutions of the so-called Kohn-Sham equations. Their resolution needs to express orbitals and density on a set of functions owing both physical and numerical properties, as explained in the second chapter. One can hardly satisfy these two properties simultaneously, that is why we are interested in orthogonal and bi-orthogonal wavelets basis, whose properties of interpolation are presented in the third chapter. We present in the fourth chapter three dimensional solvers for the Coulomb's potential, using not only the preconditioning property of wavelets, but also a multigrid algorithm. Determining this potential allows us to solve the self-consistent Kohn-Sham equations, by an algorithm presented in chapter five. The originality of our method consists in the construction of the stiffness matrix, combining a Galerkin formulation and a collocation scheme. We analyse the approximation properties of this method in case of linear Hamiltonian, such as harmonic oscillator and hydrogen, and present convergence results of the DFT for small electrons. Finally we show how orbital compression reduces considerably the number of coefficients to keep, while preserving a good accuracy of the fundamental energy. (author)

  16. Electron spin resonance studies of gamma irradiated saccharides. Etudes par resonance paramagnetique electronique de saccharides soumis a un rayonnement gamma

    Energy Technology Data Exchange (ETDEWEB)

    Raffi, J.; Thiery, C.; Battesti, C.; Agnel, J.P.; Triolet, J.; Vincent, P. (CEA Centre d' Etudes de Cadarache, 13 - Saint-Paul-lez-Durance (France). Dept. de Physiologie Vegetale et Ecosystemes)

    1993-04-01

    The radiolysis mechanism of several saccharides was studied in order to understand the radiolysis mechanism of starches. Electron Spin Resonance first performed in powder state did not allow determination of the chemical structure of the induced radicals. The spin-trapping method combined with HPLC however, followed by ESR spectra analysis with the 'Voyons' simulation program was applied to the study of glucose, glucose oligomers and disaccharides. We were thus able to further our understanding of the radiolysis mechanism of starches. 2 tabs., 4 figs.

  17. Paramagnetic resonance and electronic conduction in organic semiconductors; Resonance paramagnetique et conduction electroniques dans les semi-conducteurs organiques

    Energy Technology Data Exchange (ETDEWEB)

    Nechtschein, M. [Commissariat a l' energie atomique et aux energies alternatives - CEA, Laboratoire de Resonance Magnetique (France)

    1963-07-01

    As some organic bodies simultaneously display semi-conducting properties and a paramagnetism, this report addresses the study of conduction in organic bodies. The author first briefly recalls how relationships between conductibility and Electron Paramagnetic Resonance (EPR) can be noticed in a specific case (mineral and metallic semiconductors). He discusses published results related to paramagnetism and conductibility in organic bodies. He reviews various categories of organic bodies in which both properties are simultaneously present. He notably addresses radical molecular crystals, non-radical molecular crystals, charge transfer complexes, pyrolyzed coals, and pseudo-ferromagnetic organic structures. He discusses the issue of relationships between conduction (charge transfer by electrons) and ERP (which reveals the existence of non-paired electrons which provide free spins)

  18. Electronique appliquée, électromécanique sous Simscape & SimPowerSystems (Matlab/Simulink)

    CERN Document Server

    Mokhtari, Mohand

    2012-01-01

    Cet ouvrage permet d'apprendre à utiliser les Outils Simscape et SimpowerSystems pour modéliser et simuler des circuits électroniques, électromécaniques et électronique de puissance. Pour utiliser ces deux outils, la connaissance de MATLAB et SIMULINK est indispensable. Cet ouvrage possède trois types de chapitres: prise en main de l'outil, description des différentes bibliothèques avec quelques applications et enfin chapitre d'applications très utilisées dans les domaines universitaires et industriels.

  19. Proprietes optiques dans l'infrarouge lointain et de transport electrique de systemes electroniques a basse dimensionalite

    Science.gov (United States)

    Lefebvre, Jacques

    Cette these presente une etude experimentale de deux systemes ayant des proprietes physiques particulieres decoulant de leur caractere anisotrope. Le premier systeme est un conducteur organique quasi-unidimensionnel, le sel de Bechgaard (TMTSF)sb2ClOsb4. Le second est un systeme mesoscopique base sur une heterostructure a base de GaAs/Alsb{x}Gasb{1-x}As pour lequel la dimensionalite peut etre variee continuement entre deux et un. En dimension un, ce systeme porte le nom de fil quantique. Pour le sel de Bechgaard (TMTSF)sb2ClOsb4, une mesure de la photoconductivite dans l'infrarouge lointain a permis d'identifier une resonance dans la phase onde de densite de spin sous champ magnetique (ou ODSIC). Cette resonance, visible dans la gamme de longueurs d'onde entre 410 et 599 mum, se deplace vers les forts champs magnetiques avec l'augmentation de l'energie du photon. Malgre qu'elle s'apparente a une resonance cyclotron, un calcul theorique du coefficient d'absorption a montre qu'elle est intimement liee a la phase ODSIC et que son energie est donnee par sqrt{4deltasbsp{N}{2}+omegasbsp{c}{2}} avec deltasb{N}, l'amplitude de la bande interdite ODSIC au niveau de Fermi et omegasb{c}, l'energie cyclotron. Le gaz d'electrons dans une heterostructure a base de GaAs/Alsb{x}Gasb{1-x}As a ete etudie dans les regimes dimensionnels entre deux et un (de 2D a quasi-1D en passant par quasi-2D). En combinant des mesures de transport electrique a des mesures de transmission optique dans l'infrarouge lointain obtenues quasi-simultanement sur un meme echantillon, plusieurs conclusions emergent. Entre autres, trois regimes de modulation sont identifies et a leurs frontieres, des signes distinctifs apparaissent autant dans les mesures de transport que dans les mesures de la transmission optique. Une analyse globale permet de degager une vue coherente des modes collectifs dans les differents regimes dimensionnels.

  20. Electronic Information Management for PfP Nations (La gestion electronique des informations pour les pays du PfP)

    Science.gov (United States)

    2003-04-01

    the mind. Chicago: University of Chicago Press. Lindley, J.A. (2000). Strategic issues in electronic librarianship . Bilgi Dünyası, 1(2): 330-341. Lyman...Issues in Science and Technology Librarianship , Summer 2001. [Online]. Available: http://www.library.ucsb.edu/istl/01- summer/refereed.html [4 June... Librarianship 34, Spring 2002. [Online]. Available: http://www.istl.org/02-spring/ article3.html [4 June 2002]. Luce, R. (2001). E-prints intersect the

  1. Some techniques for studying actomyosin by electron microscopy; Quelques techniques d'etude de l'actomyosine par microscopie electronique

    Energy Technology Data Exchange (ETDEWEB)

    Herzberg, M [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires. Departement de Biologie

    1967-07-01

    A method has been developed for shadowing using a platinum-carbon alloy; it has been applied to the study of the interaction of actomyosin with its substrate ATP. The results obtained seem to favour the hypothesis of a dissociation of the actomyosin into its two components: actin and myosin. Pictures have been obtained showing particles resembling non-polymerized myosin but no rigorous proof of this exists. (author) [French] Une methode d'ombrage par un alliage de platine et carbone a ete mise au point et appliquee a l'etude de l'interaction de l'actomyosine et de son substrat l'ATP. Les resultats obtenus semblent pencher en faveur de la these d'une dissociation de l'actomyosine en ses deux constituants: l'actine et la myosine. Des images ont ete obtenues montrant des particules dont l'identite avec la myosine non polymerisee reste a demontrer plus rigoureusement. (auteur)

  2. De waarde van preventieve adviezen en keuringen bij beginnende hardlopers met het oog op cardiovasculaire gebeurtenissen en blessures : The value of preventive advice and examination focusing on cardiovascular events and injury for novice runners

    NARCIS (Netherlands)

    Zwerver, J.; Bessem, B.; Buist, I.; Diercks, R.L.

    2008-01-01

    - Novice runners often seek advice from a physician about training responsibly. Common concerns include sudden cardiac arrest, advice on running injuries and how to avoid these events. - Cardiologic screening and ergometry are only beneficial if the athlete has a high-risk profile. - In the world of

  3. Alcohol consumption and risk of cardiovascular disease and type 2 diabetes : population-based studies and physiological interventions = Alcoholconsumptie en risico op cardiovasculaire ziekten en type 2 diabetes : populatiestudies en fysiologische interventies

    OpenAIRE

    Beulens, J.W.J.

    2007-01-01

    Research described in this thesis provides evidence for a causal inverse relation of moderate alcohol consumption with cardiovascular disease and type 2 diabetes. First, it showed that these inverse associations are consistent over different populations such as hypertensive men and older women, both at increased risk of those diseases. Increased cholesterol efflux and adiponectin concentrations after moderate alcohol consumption are a plausible mechanism to explain the associations. Finally, ...

  4. Alcohol consumption and risk of cardiovascular disease and type 2 diabetes : population-based studies and physiological interventions = Alcoholconsumptie en risico op cardiovasculaire ziekten en type 2 diabetes : populatiestudies en fysiologische interventies

    NARCIS (Netherlands)

    Beulens, J.W.J.

    2007-01-01

    Research described in this thesis provides evidence for a causal inverse relation of moderate alcohol consumption with cardiovascular disease and type 2 diabetes. First, it showed that these inverse associations are consistent over different populations such as hypertensive men and older women, both

  5. Beyond territory and scarcity - exploring conflicts over natural resource management

    DEFF Research Database (Denmark)

    Ressources management, enviromental degradation, natural resources, conflicts, boundaries, Africa......Ressources management, enviromental degradation, natural resources, conflicts, boundaries, Africa...

  6. Foreword

    DEFF Research Database (Denmark)

    Birch-Thomsen, Torben

    2005-01-01

    Ressources management, enviromental degradation, natural resources, conflicts, boundaries, Africa......Ressources management, enviromental degradation, natural resources, conflicts, boundaries, Africa...

  7. Information du Contexte comme une Ressource : Une Approche Orientée Service pour la Sensibilité au Contexte

    OpenAIRE

    Romero , Daniel

    2011-01-01

    Nowadays, ubiquitous environments become part of our daily lives. At home, work, cars, hotels, supermarkets and others public spaces we find technologies (electronics and computational elements) that try to make our life simpler and easier in a transparent way. In recent years, the potential of these environments is more and more exploited with the advent and widespread usage of smartphones. This kind of devices enables the execution of applications that are able to adapt seamlessly to the cu...

  8. VALORISATION DES RESSOURCES EN EAU EN GUINEE EN VU D’UN DEVELOPPEMENT ECONOMIQUE, SOCIAL ET DURABLE

    Directory of Open Access Journals (Sweden)

    Selly CAMARA

    2017-05-01

    Full Text Available The Republic of Guinea has a rich and diversified hydrological potential. Several rivers in the sub region have their source. The hydrographic network comprises 1161 rivers, grouped into 23 watersheds. The country has 14 international rivers, including the Niger River, whose basin is shared by nine countries. Unfortunately, water resources are now threatened by anthropogenic activities of diverse origins (extensive agriculture, open-pit mining, illegal fishing, bush fires, making cooked bricks along streams, etc. and the adverse effects of climate change. Moreover, the institutional and legal aspects are not conducive to the sustainable management of water resources. The impact of water shortage will be felt on all socio-economic activities. The agriculture sector is the main user of water in the country, droughts and recurrent floods have led to a decline in cereal food supplies. The country has a high hydroelectric potential (6,000 MW, unfortunately, only 6% of its potential is used. In order to meet its international commitments to reduce its greenhouse gas emissions, by 2030, the country will have to quintuple its hydroelectric production, which constitutes clean energy. The drinking water supply sector remains confronted with the low capacity of production and treatment of water. The management of water resources in the country is based on general plans for water development elaborated between 1978 and 1982. However, the country seeks to have a national policy for integrated water resources management and development of an action plan focusing on taking into account cooperation on shared watersheds.

  9. Huiles et corps gras végétaux : ressources fonctionnelles et intérêt nutritionnel

    Directory of Open Access Journals (Sweden)

    Morin Odile

    2012-03-01

    Full Text Available The wide variety of oleaginous resources potentially provides to industrial users a wide range of fats and oils, and so, a large range of properties. But less than 10 vegetable fats and oils – such as palm and its fractions, soybean, rapeseed, sunflower, cotton, peanut and olive oils – represent more than 90 % of the world production. So, these few vegetable fats and oils will have to respond simultaneously to numerous expectations, depending on the user, such as providing optimized nutrients and offering the texture looked forward or resisting to an established cooking temperature. Innovation (use of new variety with modified compositions, existing “niche” oil or completely new resource could be an option to solve a specific issue, even if economical or regulatory constraints may not favor such alternatives. After summarizing vegetable fats and oils composition and the properties of fatty acids, this paper presents not only optimized processes allowing extraction of compounds of interest, but also processes for the conversion and enlargement of oils and fats functionalities in order to answer to the different and specific expectations of industrial users and consumers.

  10. Ressources libres et qualité du téléenseignement en Asie | Page 2 ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Openness and quality in Asian distance education : sub-project 7; a study of the ... technologies for enriching clinical practicum in nursing in the Philippines ... to be funded by Canada's International Development Research Centre (IDRC).

  11. Law 15.809 National budget of ressources and expenditure, it approve for the actually government period

    International Nuclear Information System (INIS)

    1986-01-01

    The articles 340,341,342,343 of the budget law 115.809 treat the following topics: creation of the National Commission of Atomic Energy with the National Direction of Nuclear Technology in the Uruguay,duties, radiation protection taxs

  12. Hvordan påvirker indvandrernes integration, ressourcer og diaspora deres bosætningspræferencer?

    DEFF Research Database (Denmark)

    Andersen, Hans Skifter

    Etniske minoriteters boligønsker må i vid udstrækning antages, at have de samme årsager, som generelt er fundet i forbindelse med studier af boligvalg i Danmark og andre europæiske lande. Men indvandreres bosætning i Danmark og andre lande afviger så meget fra den indfødte befolknings, at den ikk...

  13. Et benchmark studie af menneskelige ressourcer på tværs af OECD-landene

    DEFF Research Database (Denmark)

    Klynge, Alice Heegaard; Riis, Annemarie Munk

    and Finland make up the top 3 in terms of human resources. The three countries significantly outperform all other countries. At the same time the United States, Sweden and Finland have excellent framework conditions. Denmark’s performance in terms of human resources and the quality of framework conditions...... approach compared to other benchmarking methods. The FORA/OECD approach not only shows how countries perform in a specific area, it also tests the link between framework conditions and performance in the area of human resources. Based on available data the analysis shows that the United States, Sweden...... is solid. However, it will take an additional effort to bring Denmark in line with the top-performing countries....

  14. Modélisation économique des ressources en eau dans la zone de Souss-Massa

    Directory of Open Access Journals (Sweden)

    Fouad ELAME

    2018-03-01

    Full Text Available The Souss-Massa basin is providing most of the Moroccan agricultural exports and covers more than ten months of the food system needs in the country. However, the basin faces recurrent droughts exacerbated by climate change. Moreover, agriculture intensification based on the intensive use of irrigation decrease the groundwater potential and makes water resources even more limited and thus more expensive to extract. Therefore, all development activities will be constrained by scarcity of water resources in the area if no appropriate institutional and management strategies are implemented. This article presents a literature review of the main economic models that have been developed for water resources management. A critical analysis of different methods and models frequently used in the analysis of water economics suggests raising some methodological limits and highlighting the need to use other methods and tools that are more useful. The last part of this article analyzes the current state of water resources and the expected impact of climate change.

  15. Gestion des ressources côtières et marines dans les Caraïbes ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    CERMES policy perspectives : perspectives on resource management and environmental policy from the Centre for Resource Management and Environmental Studies (CERMES), Faculty of Pure and Applied Sciences, University of West Indies, Cave Hill Campus,... Rapports. Supplement to the report of the MarGov project ...

  16. Hydrogéologie et vulnérabilité à la pollution des ressources en eau ...

    African Journals Online (AJOL)

    consommation excessive d'eau, un problème de vulnérabilité à la pollution ..... formations aquifères varie entre 50 m au Nord-Est et 140 m dans la partie centrale. ... La variation de la conductivité électrique de la nappe libre dans la plaine de ...

  17. Utilisation avisée des ressources bioénergétiques aux fins de l ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Social life cycle assessment : a comparison of wastewater treatment facilities in Mexico. 51142. Rapports. Social life cycle assessment : a comparison of wastewater treatment facilities in Mexico. Téléchargez le PDF. Rapports. Informe técnico final / Water and Sanitation : LAC Cities Adapting to Climate Change by Making ...

  18. Une ressource pédagogique pour l'enseignement par simulation : cas des panneaux photovoltaïques

    OpenAIRE

    Motahhir , Saad; Ghzizal , Abdelaziz El; Sebti , Souad; Derouich , Aziz

    2015-01-01

    International audience; L'objectif de cet article est de présenter une approche pédagogique dédiée à l'enseignement des panneaux photovoltaïques (PV) aux différents niveaux d'études (lycée, bac+2, bac+3, bac+5), ça pour les écoles qui ont un problème de manque de matériels ou qui n'ont pas les moyens pour les acheter, ceci en utilisant des logiciels de prototypage et de modélisation/simulation à coût réduit (PSIM et MATLAB/SIMULINK), en plus cet article montre aussi comment utiliser ces logic...

  19. Mise en place d'une collection de ressources génétiques du mil ...

    African Journals Online (AJOL)

    Le mil est une céréale importante pour l'alimentation humaine. La Côte d'Ivoire représente un des centres de production et de consommation. Afin de collecter, conserver et étudier les variabilités existantes, une seconde mission a été effectuée dans les zones de culture de cette céréale en 1989 et 1990, faisant suite à la ...

  20. Evaluation des complications cardiaques chez les hémodialysés ...

    African Journals Online (AJOL)

    Introduction: L'évaluation cardiovasculaire est essentielle en hémodialyse périodique car les affections cardiovasculaires sont la première cause de mortalité chez les hémodialysés chroniques. Nous avons conduit cette étude afin de déterminer la prévalence et le type des différentes complications cardiovasculaires et ...

  1. Comparative performance of fluorescent iron-core ballasts and electronic ballasts. Rendement comparatif des ballasts a noyau de fer et des ballasts electroniques pour eclairage fluorescent

    Energy Technology Data Exchange (ETDEWEB)

    Pasini, I

    1987-01-01

    Commercially available one- and two-lamp fluorescent luminaires were tested, and a number of electrical parameters were measured using varying combinations of lamps and either iron-core or electronic ballasts. Comprehensive photometric tests and thermal measurements were also conducted. The test results were tabulated and compared. The performance of the iron-core ballasts was found to be sufficiently close to nominally rated values to not raise concerns. Results from testing the electronic ballasts showed that the user has to be careful when selecting these ballasts, as they far exceed standard specification limits for current and voltage crest factors. All other electrical, photometric and thermal parameters are within accepted levels. An economic analysis was undertaken to determine cost benefits and payback periods for using electronic ballasts, the use of which will result in higher efficiency and lower power consumption. A project life of 20 years was assumed, and analysis was run for a power cost of $0.04/kWh. A unit made by Fyrnetics showed the lowest total annual owning and operating costs and had a payback period of 12.1 years. 13 figs., 13 tabs.

  2. Use of commercial VDMOSFETS in an electronic system subjected to radiation; Utilisation des VDMOSFETs commerciaux dans un systeme electronique soumis aux radiations

    Energy Technology Data Exchange (ETDEWEB)

    Picard, C.; Brisset, C.; Quittard, O.; Marceau, M.; Joffre, F. [CEA Saclay, Lab. d' Electronique et de Technologie de l' Informatique, LETI, 91 - Gif-sur-Yvette (France); Hoffmann, A.; Charles, J.P. [centre Lorrain d' Optique et Electronique des Solides, Supelec, 57 - Metz (France)

    1999-07-01

    This study explores the usefulness of pre-irradiation as a hardening technique for NMOS transistors. NMOS transistors have been exposed to Co-60 gamma radiation with a dose-rate of 10 krad(SiO{sub 2})/h. The pre-irradiation technique is based on 2 phenomena occurring when the polarization is negative or equals to 0: the weak shift and the saturation of the threshold voltage.

  3. Etude, par principes premiers, des effets de la correlation entre electrons sur les proprietes electroniques et magnetiques de polymeres pontes et de supraconducteurs a haute temperature critique

    Science.gov (United States)

    Pesant, Simon

    Description of complex systems by Density functional theory is treated in this thesis. First, the Density functional theory and a few functionals used to simulate cristals are presented. Specifically, the LDA and GGA functionnals are described and their limits are exposed. Furthermore, the Hubbard model as well as the LDA+U functionnal are addressed in this chapter. These methods enable the study of highly correlated materials. Then, results obtained on polymers are summarized in two articles. The first one treats the band gap variation of ladder-type polymers compared to non ladder type ones. The second article considers small band gap polymers. In this case, it will be shown that an hybrid functional, which contains exact exchange, is required to describe the electronic properties of the polymers under study. Finally, the last chapter address the study of cuprates superconductors. The LDA+U can account for the localization of electrons in copper orbitals. Consequently, a study of the impact of this functionnal on electronic properties of cuprates is conducted. The chapter is ended by an article treating magnetic orders in doped La 2CuO4. Supplementary materials of the second article and a description of the theory of superconductivity of Bardeen, Cooper and Schrieffer are put in annex. Keywords : Electronic correlation, DFT, LDA+U, cuprates, polymers, magnetic orders

  4. Reduce consumption, improve production. Electronic adjustable speed drives and high performance motors; Consommez moins, produisez mieux. Variateurs electroniques de vitesse et moteurs performants

    Energy Technology Data Exchange (ETDEWEB)

    David, A.; Pratmarty, D.; Dessoude, M. [Electricite de France (EDF), 92 - Clamart (France). Direction des Etudes et Recherches

    1995-10-01

    The electric power consumption from electric motors accounts for up to two third of industry`s electric power consumption. When equipped with electronic adjustable speed drives (ASD), energy savings of 10 to 50 percent, with an estimated average of 25 percent, may be achieved for pumps, fans and compressors, which account for 63 percent of motor applications. The advantages of electronic ASD, the installation recommendations which should be applied, the sensibility of ASDs to power cuts and harmonics, the characteristics of high efficiency motors, the energy aspects of motors with or without electronic ASD, and the EDF-ADEME (French energy conservation agency) approach for electricity demand side management, are described

  5. Lexicon on automatic network operation. 1, computing and electronics. Lexique de l'exploitation automatisee du reseau. Fascicule 1: informatique et electronique

    Energy Technology Data Exchange (ETDEWEB)

    1986-01-01

    This bilingual dictionary covers terminology relating to the operation of electric power networks. This particular volume includes those terms applicable to data processing, computing, electricity and electronics, telecommunications, and related equipment and processes. It is intended for use by specialists working in the field of technical specifications and in computerized network operation systems as well as for use by those working with such systems. It is in two parts: French to English and English to French.

  6. Study of the electron heat transport in Tore-Supra tokamak; Etude du transport de la chaleur electronique dans le Tokamak Tore Supra

    Energy Technology Data Exchange (ETDEWEB)

    Harauchamps, E

    2004-07-01

    This work presents analytical solutions to the electron heat transport equation involving a damping term and a convection term in a cylindrical geometry. These solutions, processed by Matlab, allow the determination of the evolution of the radial profile of electron temperature in tokamaks during heating. The modulated injection of waves around the electron cyclotron frequency is an efficient tool to study heat transport experimentally in tokamaks. The comparison of these analytical solutions with experimental results from Tore-Supra during 2 discharges (30550 and 31165) shows the presence of a sudden change for the diffusion and damping coefficients. The hypothesis of the presence of a pinch spread all along the plasma might explain the shape of the experimental temperature profiles. These analytical solutions could be used to determine the time evolution of plasma density as well or of any parameter whose evolution is governed by a diffusion-convection equation. (A.C.)

  7. New generation of monolithic active pixel sensors for charged particle detection; Developpement d'un capteur de nouvelle generation et son electronique integree pour les collisionneurs futurs

    Energy Technology Data Exchange (ETDEWEB)

    Deptuch, G

    2002-09-01

    Vertex detectors are of great importance in particle physics experiments, as the knowledge of the event flavour is becoming an issue for the physics programme at Future Linear Colliders. Monolithic Active Pixel Sensors (MAPS) based on a novel detector structure have been proposed. Their fabrication is compatible with a standard CMOS process. The sensor is inseparable from the readout electronics, since both of them are integrated on the same, low-resistivity silicon wafer. The basic pixel configuration comprises only three MOS transistors and a diode collecting the charge through thermal diffusion. The charge is generated in the thin non-depleted epitaxial layer underneath the readout electronics. This approach provides, at low cost, a high resolution and thin device with the whole area sensitive to radiation. Device simulations using the ISE-TCAD package have been carried out to study the charge collection mechanism. In order to demonstrate the viability of the technique, four prototype chips have been fabricated using different submicrometer CMOS processes. The pixel gain has been calibrated using a {sup 55}Fe source and the Poisson sequence method. The prototypes have been exposed to high-energy particle beams at CERN. The tests proved excellent detection performances expressed in a single-track spatial resolution of 1.5 {mu}m and detection efficiency close to 100%, resulting from a SNR ratio of more than 30. Irradiation tests showed immunity of MAPS to a level of a few times 10{sup 12} n/cm{sup 2} and a few hundred kRad of ionising radiation. The ideas for future work, including on-pixel signal amplification, double sampling operation and current mode pixel design are present as well. (author)

  8. Study of luminous emissions associated to electron emissions in radiofrequency cavities; Etude des emissions lumineuses associees aux emissions electroniques dans les cavites hyperfrequences

    Energy Technology Data Exchange (ETDEWEB)

    Maissa, S

    1996-11-26

    This study investigates luminous emissions simultaneously to electron emissions and examines their features in order to better understand the field electron emission phenomenon. A RF cavity, operating at room temperature and in pulsed mode, joined to a sophisticated experimental apparatus has been especially developed. The electron and luminous emissions are investigated on cleaned or with metallic, graphitic and dielectric particles contaminated RF surfaces in order to study their influence on these phenomena. During the surface processing, unstable luminous spots glowing during one RF pulse are detected. Their apparition is promoted in the vicinity of the metallic particles or scratches. Two hypotheses could explain their origin: the presence of micro-plasmas associated to electronic explosive emission during processing or the thermal radiation of the melted metal during this emission. Stable luminous spots glowing during several RF pulses are also detected and appear to increase on RF surfaces contaminated with dielectric particles, leading to strong and explosive luminous emissions. Two interpretations are considered: the initiation of surface breakdowns on the dielectric particles or the heating by the RF field at temperatures sufficiently intense to provoke their thermal radiation then their explosion. Finally a superconducting cavity has been adapted to observe luminous spots, which differ from the former ones bu their star shape and could be associated to micro-plasmas, revealed by the starbursts observed on superconducting cavity walls. (author) 102 refs.

  9. Semiconductor GaAs: electronic paramagnetic resonance new data; GaAs semi-isolant: nouvelles donnees de resonance paramagnetique electronique

    Energy Technology Data Exchange (ETDEWEB)

    Benchiguer, T.

    1994-04-01

    The topic of this study was to put to the fore, thanks to our electron spin resonance experiments, one charge transfer process, which was optically induced between the deep donor As{sup +}{sub G}a and the different acceptors, which were present in the material. We described these processes through a theoretical model, which we named charge transfer model. With this latter, we were able to trace a graph network, representing the As{sup +}{sub G}a concentration kinetics. Then we verified the compatibility of our model with one transport experiment. One experimental verification of our model were delivered, thanks to neutronic transmutation doping. The following stage was the study of defects, induced by thermal strains, to which the crystal was submitted during the cooling phase. At last we wanted to get round the non solved super hyperfine structure problem for GaAs by studying another III-V material for which she was resolved, namely gallium phosphide. (MML). 150 refs., 72 figs., 16 tabs., 3 annexes.

  10. NMR of proteins (4Fe-4S): structural properties and intramolecular electron transfer; RMN de proteines (4Fe-4S): proprietes structurales et transfert electronique intramoleculaire

    Energy Technology Data Exchange (ETDEWEB)

    Huber, J G

    1996-10-17

    NMR started to be applied to Fe-S proteins in the seventies. Its use has recently been enlarged as the problems arising from the paramagnetic polymetallic clusters ware overcome. Applications to [4Fe-4S] are presented herein. The information derived thereof deepens the understanding of the redox properties of these proteins which play a central role in the metabolism of bacterial cells. The secondary structure elements and the overall folding of Chromatium vinosum ferredoxin (Cv Fd) in solution have been established by NMR. The unique features of this sequence have been shown to fold as an {alpha} helix at the C-terminus and as a loop between two cysteines ligand of one cluster: these two parts localize in close proximity from one another. The interaction between nuclear and electronic spins is a source of additional structural information for (4Fe-AS] proteins. The conformation of the cysteine-ligands, as revealed by the Fe-(S{sub {gamma}}-C{sub {beta}}-H{sub {beta}})Cys dihedral angles, is related to the chemical shifts of the signals associated with the protons of these residues. The longitudinal relaxation times of the protons depend on their distance to the cluster. A quantitative relationship has been established and used to show that the solution structure of the high-potential ferredoxin from Cv differs significantly from the crystal structure around Phe-48. Both parameters (chemical shifts and longitudinal relaxation times) give also insight into the electronic and magnetic properties of the [4Fe-4S] clusters. The rate of intramolecular electron transfer between the two [4FE-4S] clusters of ferredoxins has been measured by NMR. It is far slower in the case of Cv Fd than for shorter ferredoxins. The difference may be associated with changes in the magnetic and/or electronic properties of one cluster. The strong paramagnetism of the [4Fe-4S] clusters, which originally limited the applicability of NMR to proteins containing these cofactors, has been proven instrumental in affording new information about the structural and kinetic properties of such proteins. (author).

  11. Conducting polymers and hybrid nano-materials for electrochemical storage; Polymeres conducteurs electroniques et nanomateriaux hybrides pour le stockage de l'energie

    Energy Technology Data Exchange (ETDEWEB)

    Mallouki, M.

    2006-02-15

    In this work, we report first on the preparation of nano-structures based on poly-pyrrole and iron oxide nano-particles by oxidative polymerisation of pyrrole in colloidal solution of Fe{sub 2}O{sub 3}. The conductivity and the morphology of nano-composites were studied and related to the doping agent role and the weight ratio (Fe{sub 2}O{sub 3}/PPy). The specific capacity measurement on the composite electrode (based on the nano-composite, acetylene black and binders) indicate a significant enhancement of charge storage for nano-composites compared to pure poly-pyrrole. Then, we investigated the synthesis and characterisation of composite electrode based on poly 3-methyl-thiophene (PMeT), which depend on different methods of preparation, electrolyte and doping potential. Finally, a room temperature ionic liquid (RTIL) such as imidazolium tri-fluoro-methane-sulfonimide (EMITFSI), was used and seem to be a promising electrolyte since it increases further the capacity with a high stability during charge-discharge processes. (author)

  12. Efficiency evaluation of an electronic equipment: availability,reliability and maintenance; Notion d'efficacite d'un equipement electronique: disponibilite, fiabilite et maintenabilite

    Energy Technology Data Exchange (ETDEWEB)

    Guyot, C

    1966-07-01

    This concept of efficiency often called ''system effectiveness'', is presented and analyzed in terms of reliability and maintenance. It allows to define the availability factor of an electronic equipment. A procedure of evaluation is proposed. (A.L.B.)

  13. Design and electronic power supply of double salience variable reluctance machines; Conception et alimentation electronique des machines a reluctance variable a double saillance

    Energy Technology Data Exchange (ETDEWEB)

    Multon, B

    1994-05-15

    This work deals with the optimization of double salience variable reluctance motors with electronic switching. It includes the control laws, the electromagnetic structure and the direct and indirect self-driving sensors. The first chapter presents the state-of-the-art of double salience reluctance machines, their characteristics, their inverters and the evolutions of their electromagnetic structure. Chapters 2 and 3 treat of the optimization of power supplies and of the electromagnetic structure, respectively. Finally, the last chapter treats of original solutions of position measurement for the self-control, one using a variable reluctance sensor, and the other using an indirect sensor. The impact of the motor characteristics on the power supply has been analyzed with the optimization of the control laws in permanent regime and low torque undulation regime. The influence of the motor structure geometry on the electromagnetic characteristics has been studied using analytic methods coupled with punctual finite-element calculations. Using a particular example, a self-oscillating power supply mode has been implemented in order to reduce the losses and the electromagnetic pollution. (J.S.)

  14. Semiconductor device models for circuit simulation power electronics; Modeles de composants semiconducteurs pour la simulation des circuits en electronique de puissance

    Energy Technology Data Exchange (ETDEWEB)

    Berraies, M.O.

    1998-09-10

    In this thesis, an alternative strategy based on a regional approach to modeling and a new partition of the model library in the simulation is proposed. The main objective is to substitute for the usual concept of `one device, on model` that of an adaptable assembly of a limited number of submodels associated with well-identified regions of semiconductor structures. In other words, the library will only contain the primitive building-blocks of the power device models. This strategy guarantees the compatibility of the various semiconductor models in terms of physical concepts, validity domain, accuracy, homogeneity of parameter identification procedures, similarly of implementation in the simulator. This approach has been applied to PIN diodes and IGBTs for experimental validation. The next step consisted on the simulation of circuit involving several interacting devices. A simple IGBT/PIN diode chopper cell has been chosen. The results obtained compare well with experiment. This demonstrates the consistency of the proposed approach. (author) 43 refs.

  15. Numerical study of the atomic and electronic structure of some silicon grain boundaries; Etude numerique de la structure atomique et electronique de quelques joints de grains du silicium

    Energy Technology Data Exchange (ETDEWEB)

    Torrent, M

    1996-07-01

    This work contributes to the theoretical study of extended defects in covalent materials. The study is especially devoted to the tilt grain boundaries in silicon as a model material. The theoretical model is based on the self-consistent tight-binding approximation and is applied within two numerical techniques: the fast 'order N' density-matrix method and the diagonalization technique which allows the sampling of the reciprocal space. Total energy parameters of the model have been fitted in order to reproduce the silicon band structure (with a correct gap value) and the transferability of crystalline and mechanical properties of this material. A new type of boundary conditions is proposed and tested. These conditions, named 'ante-periodic' or 'Moebius', allow only one grain boundary per box instead of two and decrease the CPU time by a factor of two. The model is then applied to the study of the {sigma}=25 [001] (710) grain boundary. The results show the possible presence in this boundary of low energy non-reconstructed atomic structures which are electrically active. This confirms what had been suggested by some experimental observations. The same study is also performed for the {sigma}=13 [001] (510) grain boundary. In order to compare the intrinsic electrical activity in the previous grain boundaries with the one induced by impurities, a total energy parametrization for the silicon-nickel bond is achieved and used in preliminary calculations. Finally the two variants of the {sigma}=11 [011] (2-33) interface are studied, especially their respective interfacial energies. The result disagrees with previous calculations using phenomenological potentials. (author)

  16. Conference Proceedings of Machine Intelligence for Aerospace Electronic Systems Held in Lisbon, Portugal on 13-16 May 1991 (L’Intelligence Artificielle dans les Systemes Electroniques Aerospatiaux)

    Science.gov (United States)

    1991-09-01

    primrily in the diagnostic Response to Theme (3). The MI programs of and navigation arena . Also, a USA Navy the future will provide choices for the program...a software research arena ) from which to chose; engineering tool. however, there was a sufficient amount of activity to report from each member nation...weights Z W2 X2.6 2 vProcessingn W Element " °tu X m n (Neuron) VIAJ X X 1n 91-15516’IIIIIIII 9-4 Each processing element may have many input signals

  17. The promises of fuel cells seduce the electronics manufacturers; Les promesses des piles a combustible seduisent les geants de l'electronique

    Energy Technology Data Exchange (ETDEWEB)

    Chalmet, E.; Maridet, R.

    2001-07-01

    The cell using the hydrogen seems to be an attractive alternative energy source. Useful for the portable telephones, the automobiles or in the houses, it may cover a market of 60 milliards of dollars in 2010. (A.L.B.)

  18. Conducting polymers and hybrid nano-materials for electrochemical storage; Polymeres conducteurs electroniques et nanomateriaux hybrides pour le stockage de l'energie

    Energy Technology Data Exchange (ETDEWEB)

    Mallouki, M

    2006-02-15

    In this work, we report first on the preparation of nano-structures based on poly-pyrrole and iron oxide nano-particles by oxidative polymerisation of pyrrole in colloidal solution of Fe{sub 2}O{sub 3}. The conductivity and the morphology of nano-composites were studied and related to the doping agent role and the weight ratio (Fe{sub 2}O{sub 3}/PPy). The specific capacity measurement on the composite electrode (based on the nano-composite, acetylene black and binders) indicate a significant enhancement of charge storage for nano-composites compared to pure poly-pyrrole. Then, we investigated the synthesis and characterisation of composite electrode based on poly 3-methyl-thiophene (PMeT), which depend on different methods of preparation, electrolyte and doping potential. Finally, a room temperature ionic liquid (RTIL) such as imidazolium tri-fluoro-methane-sulfonimide (EMITFSI), was used and seem to be a promising electrolyte since it increases further the capacity with a high stability during charge-discharge processes. (author)

  19. Numerical study of the atomic and electronic structure of some silicon grain boundaries; Etude numerique de la structure atomique et electronique de quelques joints de grains du silicium

    Energy Technology Data Exchange (ETDEWEB)

    Torrent, M

    1996-07-01

    This work contributes to the theoretical study of extended defects in covalent materials. The study is especially devoted to the tilt grain boundaries in silicon as a model material. The theoretical model is based on the self-consistent tight-binding approximation and is applied within two numerical techniques: the fast 'order N' density-matrix method and the diagonalization technique which allows the sampling of the reciprocal space. Total energy parameters of the model have been fitted in order to reproduce the silicon band structure (with a correct gap value) and the transferability of crystalline and mechanical properties of this material. A new type of boundary conditions is proposed and tested. These conditions, named 'ante-periodic' or 'Moebius', allow only one grain boundary per box instead of two and decrease the CPU time by a factor of two. The model is then applied to the study of the {sigma}=25 [001] (710) grain boundary. The results show the possible presence in this boundary of low energy non-reconstructed atomic structures which are electrically active. This confirms what had been suggested by some experimental observations. The same study is also performed for the {sigma}=13 [001] (510) grain boundary. In order to compare the intrinsic electrical activity in the previous grain boundaries with the one induced by impurities, a total energy parametrization for the silicon-nickel bond is achieved and used in preliminary calculations. Finally the two variants of the {sigma}=11 [011] (2-33) interface are studied, especially their respective interfacial energies. The result disagrees with previous calculations using phenomenological potentials. (author)

  20. Adaptation to the electronics of fast and highly efficient fission chambers; Adaptation a l'electronique de chambres a fission rapides et de grande efficacite

    Energy Technology Data Exchange (ETDEWEB)

    Buisson, Jacques

    1968-09-04

    When designing a fast and highly efficient sensor, not only optimal values of the sensor per se (nature of the filling gas, pressure, electric field, etc.), but also its adaptation to the cable of connection to the electronics must be taken into account. The author reports the development of the expression of the characteristic impedance of fission chambers and the determination of elementary tubes. He reports the theoretical study of the amplitude of pulses produced by a sensor in the case of a non-adapted sensor and in the case of an adapted sensor. It appears that an adapted chamber does not possess only benefits, but is an interesting solution only when the sensor collection time is very short and when the compliance with its speed is the essential objective. Some recommendations are made for the electronics characteristics, and for the connection cable (very low losses, which means a greater diameter than the current one)

  1. Materials contamination control in the microelectronic industry; Controle de la contamination des materiaux dans l`industrie de la micro-electronique

    Energy Technology Data Exchange (ETDEWEB)

    Tardif, F

    1994-12-31

    This paper deals with many aspects of the contamination of materials in the microelectronic industry. The contamination`s control of chemicals, process gases, silicon and the survey of the ions free water`s purity are treated. (TEC). 29 figs., 7 tabs.

  2. Theoretical and experimental study of cyclotronic waves in a fusion plasma; Etude theorique et experimentale des ondes cyclotroniques electroniques dans un plasma de fusion

    Energy Technology Data Exchange (ETDEWEB)

    Vezard, D

    1994-12-20

    This thesis presents a study concerning cyclotronic waves in a plasma. It starts with an illustration of the elementary interaction between electromagnetic waves and matter.It shows that electrons from tokamak absorbs waves at cyclotronic frequency. Cyclotronic waves are studied by solving the dispersion relation in plasma; it concerns polarisation, absorption, dispersion, extinction. Then, classical theories are reminded in order to speak about decoupled electrons and their interactions. Absorption and emission properties of cyclotronic waves by electrons from a queue are described. After that, cyclotronic waves propagation is studied taking into account resonance. The last part of this thesis is dedicated to the electronic distribution function that is made by a wave spectra at a inferior hybrid frequency. (TEC). 129 refs., 75 figs.

  3. New generation of monolithic active pixel sensors for charged particle detection; Developpement d'un capteur de nouvelle generation et son electronique integree pour les collisionneurs futurs

    Energy Technology Data Exchange (ETDEWEB)

    Deptuch, G

    2002-09-01

    Vertex detectors are of great importance in particle physics experiments, as the knowledge of the event flavour is becoming an issue for the physics programme at Future Linear Colliders. Monolithic Active Pixel Sensors (MAPS) based on a novel detector structure have been proposed. Their fabrication is compatible with a standard CMOS process. The sensor is inseparable from the readout electronics, since both of them are integrated on the same, low-resistivity silicon wafer. The basic pixel configuration comprises only three MOS transistors and a diode collecting the charge through thermal diffusion. The charge is generated in the thin non-depleted epitaxial layer underneath the readout electronics. This approach provides, at low cost, a high resolution and thin device with the whole area sensitive to radiation. Device simulations using the ISE-TCAD package have been carried out to study the charge collection mechanism. In order to demonstrate the viability of the technique, four prototype chips have been fabricated using different submicrometer CMOS processes. The pixel gain has been calibrated using a {sup 55}Fe source and the Poisson sequence method. The prototypes have been exposed to high-energy particle beams at CERN. The tests proved excellent detection performances expressed in a single-track spatial resolution of 1.5 {mu}m and detection efficiency close to 100%, resulting from a SNR ratio of more than 30. Irradiation tests showed immunity of MAPS to a level of a few times 10{sup 12} n/cm{sup 2} and a few hundred kRad of ionising radiation. The ideas for future work, including on-pixel signal amplification, double sampling operation and current mode pixel design are present as well. (author)

  4. Hybrid electric vehicle thermal management and study of the power electronics cooling; Gestion thermique du vehicule hybride et etude du refroidissement de l'electronique de puissance

    Energy Technology Data Exchange (ETDEWEB)

    Rouaud, C.

    2004-07-01

    For decreasing the engine's consumption and pollutant emissions, automobile makers are developing hybrid electric vehicles incorporating an electric motor and power electronics leading to new under-hood thermal constraints. This is why we first present the tests results of a new common cooling circuit for all the vehicle components. With the aim of developing new energy management strategies between the components, we have chosen the nodal method to simulate the thermal behaviour of the engine, the electric motor, the power electronics and the cooling circuit. The second part of this thesis deals with a thermal-hydraulic analysis of several power electronics cooling methods, which has led us to choose the multiple jet impingement cooling. Several tests have been made for characterising the performances of this technique and enabled us to establish an optimal configuration. The last part shows the thermal simulation results run with the help of an innovative reduction method of thermal models applied to the power electronics. This technique allowed us to have a low cost of time simulation and will permit, in the future, the real-time control of the hybrid electric vehicle components. (author)

  5. Monitoring of the current profile by using cyclotronic electron waves in tokamaks; Controle du profil de courant par ondes cyclotroniques electroniques dans les tokamaks

    Energy Technology Data Exchange (ETDEWEB)

    Dumont, R

    2001-08-01

    The subject of this thesis is the study of the cyclotronic electron wave as a monitoring tool of the current profile. The first chapter is dedicated to basic notions concerning tokamak plasmas and current generation. The second chapter is centered on the use of fast electrons to generate current and on its modelling. The propagation and absorption of the cyclotronic electron wave require a specific polarization state whose characteristics must be carefully chosen according to some parameters of the discharge, the chapter 3 deals with this topic. The absorption of a wave in a plasma depends greatly on the velocity distribution of the particles that make up the plasma and this distribution is constantly modified by the energy of the wave, so this phenomenon is non-linear and its physical description is difficult. In a case of a fusion plasma, a sophisticated approximation called quasi-linear theory can be applied with some restrictions that are presented in chapter 4. Chapters 5 and 6 are dedicated to kinetics scenarios involving the low hybrid wave and the cyclotronic electron wave inside the plasma. Some experiments dedicated to the study of the cyclotronic electron wave have been performed in Tore-supra (France) and FTU (Italy) tokamaks, they are presented in the last chapter. (A.C.)

  6. Inventory of refrigeration training in Quebec given within the framework of the intervention program of Natural Resources Canada's CETC-Varennes and the AEE of Ressources naturelles du Quebec; Inventaire de la formation en refrigeration au Quebec dans le cadre du programme d'intervention initie par le CTEC-Varennes de ressources naturelles Canada et l'AEE de ressources naturelles du Quebec

    Energy Technology Data Exchange (ETDEWEB)

    Garant, G.J. [Association des Arenas du Quebec Inc., Montreal, PQ (Canada)

    2004-03-01

    This paper relates information concerning vocational courses in refrigeration in Quebec, with reference to the newly formed National Committee on Vocational and Technical Educational Programs. The aim of the paper was to collect data on the availability of refrigeration courses. A description of course outlines was provided, with reference to requirements in high school and at the college level. Requirement details for additional courses in heating and electricity refrigeration were also provided. The status of diplomas was also discussed, with reference to employment opportunities in management and analysis upon completion of the Diploma of Collegial Studies, which requires additional courses in energy conservation. Opportunities in the labour market were reviewed, as well as information on privately run courses. Particular reference was made concerning the Canadian Energy Technology Centre (CETC) as a leading research facility for refrigeration concepts and design. It was noted that very few courses on refrigeration technology are offered at the university level, and that currently only one distance education course on refrigeration has been recognized. As a result of this investigation, the Quebec Arena Association has determined that development of new courses is a priority, especially given that only the CETC currently offers courses on refrigeration for arenas and curling rinks. New courses should focus on arena and rink refrigeration technologies, with particular reference to new technologies and developments in energy efficiency. tabs., figs.

  7. Projet de mise en valeur des ressources naturelles et de lutte contre la désertification dans la plaine côtière de Djibouti

    Directory of Open Access Journals (Sweden)

    Van Den Bussche, E.

    1988-01-01

    Full Text Available Project for rational use of the natural resources and fight against desertification in the coastal plain of Djibouti. The project pursues the rational use of natural resources and combatting desertification. The transition from an almost nomadic way of living to a sedentary one, strongly disturbs the existing equilibriums in the project area. Causes of this settling down are multiple and fortify one another. The project proposes a programme of introduction of new forage germplasm and amplification of the feeding basis, resulting from studies of different aspects of the natural environment and forage trials on the field. The aim is to combine this kind of actions with "agricultural activities" and to contact in particular the rural population which is touched by this evolution to sedentary life.

  8. Ressource-Sharing on the Tera-Flop Scale for the Biomedical Research and Care Sector - The Erasmus Computing Grid and MediGRID

    NARCIS (Netherlands)

    T.A. Knoch (Tobias)

    2008-01-01

    markdownabstractToday advances in scientific research as well as clinical diagnostics and treatment are inevitably connected with information solutions concerning computation power and information storage. The needs for information technology are enormous and are in many cases the limiting factor

  9. L’ergonomie et les chiffres de la santé au travail : ressources, tensions et pièges de Volkoff

    Directory of Open Access Journals (Sweden)

    Esther Cloutier

    2005-11-01

    Full Text Available Ce livre regroupe quatre textes et une recension de bases de données d’auteurs différents qui s’intéressent à l’utilisation de données quantitatives pour l’amélioration de la compréhension des relations entre le travail et la santé principalement en ergonomie. Il est destiné aux chercheurs, enseignants, étudiants et praticiens en ergonomie. Il vise deux objectifs : 1 souligner la richesse des évaluations chiffrées et 2 présenter une lecture critique de ceux qui favorisent la quantification ...

  10. Les pratiques de sélection des exécutifs dans les entreprises multinationales : gestion des ressources humaines dans la gestion des affaires internationales.

    OpenAIRE

    Lakshman , Sangeetha

    2013-01-01

    Multinationals that are moving abroad for its subsidiary operation may use any one of the typology such as Global, Multi-domestic,Transnational, and International strategy in order to manage and maintain their business abroad. International staffing is a critical elementof the implementation of the four strategies for doing business globally. In staffing the international operation, the organization mayfollow one of the three staffing approaches or a combination of three approaches (PCN, HCN,...

  11. Accès aux ressources documentaires en situation d’autonomie: pratiques et représentations Autonomous accessing of study documents: student practices and perceptions

    Directory of Open Access Journals (Sweden)

    Christine Develotte

    2003-06-01

    Full Text Available L’intégration de la Toile dans les pratiques socio-culturelles des étudiants de certains pays est telle que leurs recherches documentaires à l’université s’effectuent, dans certains domaines, autant par le biais de données en ligne que des livres. La classe de langue a, elle aussi, la possibilité de jouer sur la diversité des supports accessibles en toute autonomie par les apprenants. Cependant les pratiques de recherche et de construction du savoir s’avèrent différentes en fonction du support à partir duquel elles s’exercent. Les représentations qui y sont associées varient également. Nous chercherons ici à préciser la nature des opérations que recouvrent ces différentes démarches de recherche à partir d’un dispositif méthodologique élaboré dans le but de rendre compte des pratiques d’apprenants de français de niveau avancé. À partir de ce protocole méthodologique, nous donnerons les résultats d’une étude menée en 2001, en Australie, auprès d’étudiants de l’université de Sydney.In some countries, the incorporation of the Internet into the socio-cultural practices of students is such that on-line documents are used alongside traditional written documents. Language classrooms also benefit from this diversity of educational supports that allow students to work autonomously. However, the information gathering and learning processes employed differ greatly according to the supports used. The values that students attach to these mediums vary greatly. We propose a methodology which will illustrate the practices of advanced French language learners. Using this protocol we will present the results of a study which was undertaken in 2001 with the students of the university of Sydney, Australia.

  12. Enjeux fonciers, exploitation des ressources naturelles et Forêts des Communautés Locales en périphérie de Kinshasa, RDC

    Directory of Open Access Journals (Sweden)

    Vermeulen, C.

    2011-01-01

    Full Text Available Land issues, exploitation of natural resources, and Forests of Rural Communities in the periphery of Kinshasa, DRC. Peri-urban forests are under strong anthropic pressure. Any activity needs a previous identification of stakeholders, landscape perception, socio-economic trends in local communities and their relationships with land and natural resources. Kinshasa (capital of Democratic Republic of Congo, DRC is a 10 millions inhabitants city with rapid growth and increasing impacts on surrounding villages linked with forest natural resources. This paper describes the relationship amongst local communities stakeholders and their relations with land areas and wood resources. Two areas surrounding Kinshasa (Bas-Congo and Bateke Plateaux are considered as major fuel-wood and charcoal supply zones for the city. Those two areas are different in terms of land pressure (very high in Bas-Congo and focused on riparian forests on Bateke Plateaux, but show the same pattern of overuse of the forest and woody natural resources. In both areas, local management of forest resources by the traditional authorities (heads of village or lineage has failed. Local population willingness for reforestation and forest restoration activities is much more important in Bas-Congo than on Bateke Plateaux. In both areas, shifting cultivation due to slash and burn practices for agricultural and charcoal practices are more and more quick. This has strong negative impact on the potential of regeneration process with local forest species. Sustainability of forest natural resources management by communities is discussed in regard to the on going negotiations on community based forest management regulations.

  13. Contrôle de gestion et gouvernance de l'université : la comptabilité comme ressource discursive de la performance

    OpenAIRE

    Caron, Marie-Andrée; Boisvert, Hugues

    2015-01-01

    International audience; Increasing budgetary constraints of higher education caused by public financing compressions tends to put forward accounting as an indisputable mechanism of governance, while it is interpreted in various ways. Researchers in the combined management and accounting fields have shown how accounting through management control is being used as a lever of action for managers. University financing and governance oscillates actually between two poles, one related to research a...

  14. Veje og vildveje til læsning som ressource: Teksthændelser i naturfagsundervisning med og uden læseguide

    DEFF Research Database (Denmark)

    Bremholm, Jesper

    det metodiske design valgt på baggrund af erfaringerne fra studiets eksplorative del kombineret med eksisterende literacy-didaktiske forskning. Konkret valgtes det ix literacy-didaktiske redskab læseguide (reading guide) hvilket tillige medførte følgende præcisering af forskningsspørgsmålets anden del...

  15. Sustainable utilization of ressources. Production of ethanol from dairy waste streams; Nachhaltige Verwertung von Wertstoffstroemen. Gewinnung von Ethanol aus einem Reststoff der Molkeverarbeitung

    Energy Technology Data Exchange (ETDEWEB)

    Benecke, Christian

    2011-07-01

    The worldwide increasing demand for cheese and dairy products leads to a steady increase of whey production. Today, whey is no more considered as waste, but serves as source for materials like lactose and proteins. At the end of this process a whey concentrate is released, which contains still a significant content of lactose. This lactose could not be obtained in the desired quality. This thesis describes a method to increase added value from the utilization-process of whey. To achieve this intent, methods where evaluated, to use the remaining lactose as a substrate for the fermentation to ethanol. Yeasts of the strain Kluyveromyces marxianus were evaluated for the use in this process. The degradation rate of the substrate and a maximized conversion were the main objectives. For the growth of the yeast cells, a method was developed, which uses only whey concentrate as substrate and avoids the usage of other materials for nutrition. The method was optimized in consideration of initial substrate concentration and degradation rate. The high content of salts in the whey concentrate leads to the further investigations of inhabitating or proliferating effects of different anions and cations on the used yeast cells. It becomes obvious, that a desalting or dilution of the used whey concentrate is mandatory. For that purpose, the nanofiltration was applied successfully to this process. The usage of not desalted whey concentrate is also possible. With an adequate dilution of the whey concentrate, relative yields of ca. 90% could be achieved. With a significant increase of the initial biomass, the duration of the fermentation process could be halved to ca. 25 h. (orig.)

  16. La confrontation entre les ressources en eau et les besoins en eau en moyenne montagne cristalline. Quelles contraintes, quels acteurs et quelles politiques de gestion ?

    OpenAIRE

    Benmalek , Yohann

    2009-01-01

    Terrain d'étude : Parc Naturel Régional du Pilat, Syndicat du Pays du Gier, SICALA Antenne de Tence.; The objective of this Doctorate was to put in adequacy water resources and water requirements on average crystalline mountain through the example of the Country of Gier, the Regional Natural reserve of Pilat and S.I.C.A.L.A. "Antenna of Tence ". This work was realized in a space of low mountain range. It corresponds so in the middle geographical in the strict sense as in a space lived by a so...

  17. Ressources et partage de l'eau dans l'oasis de Kenadsa (Sud-Ouest Algerien): approche historique et constat

    OpenAIRE

    Benmoussa, Youcef; Rezzoug, Cherif; Remini, Boualem; Belhadj, Mahdi

    2015-01-01

    Kenadsa, a peaceable oasis in southwestern Algeria, with the discovery and exploitation of coal (1917-1956), underwent graft of Western models for its development. That has cleared the oasis of the spatial dimension and transformed into a mining village by excellence. These networks of foggaras draining groundwater, enclosed in a multilayer aquifer, which becomes free on the northern border of the Ksar. There were 25 foggaras of sources (Ain), each of which had its own drainage channels to do...

  18. Ressources et partage de l'eau dans l'oasis de Kenadsa (Sud-Ouest Algerien; approche historique et constat

    Directory of Open Access Journals (Sweden)

    YOUCEF BENMOUSSA

    2015-07-01

    Full Text Available Resources And Water Sharing In The Oasis Of Kenadsa (Southwest Algeria; Historical Approach And Findings. Kenadsa, a peaceable oasis in southwestern Algeria, with the discovery and exploitation of coal (1917 - 1956, underwent graft of Western models for its development. That has cleared the oasis of the spatial dimension and tr ansformed into a mining village by excellence. These networks of foggaras draining groundwater, enclosed in a multilayer aquifer, which becomes free on the northern border of the Ksar. There were 25 foggaras of sources (Ain, each of which had its own drai nage channels to downstream gardens of Ksar. The distribution of water from these sources was ensured by a complex network, fed by drainage galleries that meander the alleys of Ksar and gives place to access points for domestic uses. The right to water is generally private property; one could dispose of according to modes of transmission of a property. It’s sharing for irrigation is governed by the volume and time. Currently, only some ten foggaras of sources that are still alive (Ain Sidi Mbarek, Ain Dir, Belkaid Ain, Ain Sheikh ..... These waters are characterized by mediocre quality (pH 7.31, CE: 4.88 ms / cm, RS 2420 mg / l Ca ++: 288.2 mg / l, SO4 -- : 468 83 mg / l..

  19. Modélisation de l'intégration de ressources TAL pour l'apprentissage des langues : la plateforme MIRTO

    Directory of Open Access Journals (Sweden)

    Claude Ponton

    2005-11-01

    Full Text Available Le présent article se focalise sur le développement d'outils de traitement automatique des langues (TAL pour l'apprentissage des langues assisté par ordinateur (ALAO. Après avoir identifié les limitations inhérentes aux outils d'ALAO dépourvus de composantes TAL, nous décrivons le cadre général du projet MIRTO, une plateforme de création d'activités pédagogiques fondé sur des outils TAL en développement au sein de notre laboratoire. Cette plateforme est organisée en quatre couches distinctes et successives : fonctions, scripts, activités et scénarios. À travers plusieurs exemples, nous expliquons en quoi l'architecture de MIRTO permet l'implantation de fonctions TAL classiques au sein de scripts, lesquels facilitent la conception, sans compétence informatique préalable, d'activités didactiques, elles-mêmes éventuellement intégrées au sein de séquences plus complexes, ou scénarios.

  20. Panorama 2010: Update on hydrocarbon resources. 1 - Petroleum liquids; Panorama 2010: Un point sur les ressources en hydrocarbures. 1 - Les liquides petroliers

    Energy Technology Data Exchange (ETDEWEB)

    Mathieu, Y.

    2010-07-01

    The level of current oil reserves would not be able to sustain the present pace of world production in the long run. Even in an energy transition context, it remains vital to mobilize new reserves to prevent a sharp decline in production. This requires the convergence of a number of technical, human, financial and political factors. (author)

  1. Panorama 2010: Update on hydrocarbon resources. 2 - Natural gas; Panorama 2010: Un point sur les ressources en hydrocarbures. 2 - Le gaz naturel

    Energy Technology Data Exchange (ETDEWEB)

    Mathieu, Y.

    2010-07-01

    Current gas reserves could sustain a slight increase in world production until 2020. The development of all existing conventional resources would bring them up to about 4.5 Tm{sup 3} by 2030. The effect of a generalized development of unconventional gas resources would be to slow down rather than postpone the decline in production. (author)

  2. Material stock in German datacenters. An inventory to determine the utilization of ressources and energy; Materialbestand der Rechenzentren in Deutschland. Eine Bestandsaufnahme zur Ermittlung von Ressourcen- und Energieeinsatz

    Energy Technology Data Exchange (ETDEWEB)

    Hintemann, Ralph; Fichter, Klaus [Borderstep Institut fuer Innovation und Nachhaltigkeit gemeinnuetzige GmbH, Berlin (Germany)

    2010-11-15

    The study ascertains the equipment and material resources of German data centres for the reference year 2008 and predicts its development until the year 2015 in two scenarios (''business as usual'' and ''Green IT''). Similar studies for other countries or regions are not known so far. In the study a methodology is developed, which allows to calculate the number of data centres in different size classes and their average equipment with IT components and infrastructure elements such as air conditioning systems and power supplies. Reference products are defined and on this basis a detailed determination of the material composition of data centre components is made. This allows to make detailed statements on the material equipment of approximately 53,000 data centres in Germany. In the year 2008 in German Data centres approx.12.000 tonnes of electronics, 17,000 tonnes of copper, 7,000 tonnes of aluminium, 11,000 tonnes of plastics and 58 000 tonnes of iron were used. The electronic material contains 1.8 tonnes of gold, 7.5 tonnes of silver and 0.8 tonnes of palladium. Nearly 30% of the materials are bound in almost 50 major data centres. In the scenario ''business as usual'' the amount of electronics in the German data centres increases from 2008 to 2015 by about 60% up to 20,000 tonnes. This includes almost 3 tonnes of gold, 21 tonnes of silver and 1.8 tonnes of palladium. The amounts of copper, aluminium and iron will increase by over 50%. Even in the scenario ''Green IT'' when the energy needs of data centres in Germany decreases by 40%, the material stock in the data centres would not reduce, especially the electronic material will increase significantly by more than 20%. The study points to significant further research. In particular there is a need to ascertain detailed data on the material composition of IT products (servers, etc.). The study stresses that in the future in addition to the issues of energy efficiency the questions of material efficiency of data centres should be regarded. Additionally the development of appropriate product design and recycling strategies for servers, storage and other data centre components should be enforced. (orig.)

  3. Impacts du changement climatique sur l'hydrologie et la gestion des ressources en eau du bassin de la Meuse (synthèse bibliographique

    Directory of Open Access Journals (Sweden)

    Bauwens, A.

    2013-01-01

    Full Text Available Impacts of climate change on hydrological regimes and water resources management in the Meuse catchment. A review. This review examines the consequences of climate change on the hydrology of the Meuse catchment and on various water-related socio-economic sectors. It sums up the different modeling approaches in hydrological modeling, placing emphasis on current modeling assumptions and the restrictions inherent within them. It is useful to consider land use evolution and adapted management within the context of climate change, particularly with reference to agriculture. More specifically, a broader usage of physically-based hydrological models would be useful in order to represent climate change scenarios and possible adaptation tracks at the catchment scale. These physically-based hydrological models are able to represent a wide range of phenomena occurring in the water-soil-plant continuum. They thus allow a refinement of global hydrological solutions at the catchment scale, especially during low flow periods. Moreover, such models pave the way for the analysis of scenarios aimed at creating adaptation in the use and management of soils.

  4. Sustainable logistics. Sustainability of logistic centres by means of evaluation of emissions, protection of ressources and energy efficiency; Sustainable logistics. Nachhaltigkeit von Logistikzentren durch Emissionsbewertung, Ressourcenschonung und Energieeffizienz

    Energy Technology Data Exchange (ETDEWEB)

    Zadek, Hartmut; Schulz, Robert (eds.)

    2011-07-01

    The discussion on climate change and availability of limited resources shows that resource conservation and energy efficiency in today's targets of companies are under-represented. Cost efficiency and increase of the shareholder value with respect to a measurable success determine the daily operations. The author of the contribution under consideration considers logistics centers and supply processes for manufacturing companies. After describing basic approaches to sustainability in logistics an inventory follows based on a study of logistics service providers and manufacturing companies. Methods and tools for the evaluation of CO{sub 2} emissions and resource consumption are presented. A guideline for the development of buildings, energy audits and renewable energies is considered, identified solutions to energy-efficient logistics and modernization are given, selected best-practice examples of sustainable logistics centers are presented. The contribution ends with strategic derivation targeted at policy and state as well as companies and management.

  5. Ressourceneffiziente Produktion - Innovationsallianz Green Carbody Technologies: Vortrag gehalten auf dem 11. Cottbuser Leichtbauworkshop, Energie als Ressource, 28. und 29. Mai 2013, Cottbus

    OpenAIRE

    Putz, Matthias

    2013-01-01

    Produktionstechnik im Wandel, "Treiber" für Energie- und Ressourceneffizienz. Die Produktionstechnik muss sich den Herausforderungen Endlichkeit von fossilen Ressourcen, demografischer Wandel, Klimawandel, steigender Verbrauch an Elektrizität, Globalisierung und Wohlstand, unter dem Ansatz der Machbarkeit der Effizienz, stellen. Mit dem E3-Konzept -effiziente Produktionstechnik, emissionsneutrale, energieautarke Fabrik, Einbindung des Menschen- forscht die FHG an Lösungen für eine ressourcene...

  6. Recommandation argumentée de ressources pédagogiques au sein d'un écosystème apprenant

    OpenAIRE

    Chahrazed , Mediani; Abel , Marie-Hélène

    2016-01-01

    National audience; Un écosystème apprenant est un ensemble cohérent composé de biocènes de formation favorisant un « apprentissage ensemble » basé sur l'échange et le partage de connaissances et/ou de compétences pour mieux réussir un projet commun. Les biocènes de formation sont variés et profitent de l'avancée des technologies de l'information et de la communication. Ainsi, la plateforme MEMORAe est un environnement de collaboration organisé autour d'un ensemble d'écosystèmes apprenants par...

  7. Algorithmes adaptatifs et efficaces de partage de ressources radio pour les communications de type MTC : cas de coexistence H2H/M2M

    OpenAIRE

    Hamdoun , Safa

    2017-01-01

    The Internet-of-Things (IoT) refers to the ever-growing network of everyday objects that interconnect to each other or to other Internet-enabled systems via wireless sensors attached to them. IoT envisions a future where billions of smart devices will be connected and managed through a range of communication networks and cloud-based servers, enabling a variety of monitoring and control applications. Machine-to-Machine (M2M) communications supported by cellular networks, also known as Machine-...

  8. L’accès aux ressources en création d’entreprise: vers une reconsidération des facteurs sociaux

    Directory of Open Access Journals (Sweden)

    Amina Omrane

    2015-03-01

    Full Text Available Les travaux de recherche en entrepreneuriat ont largement mis en valeur le capital relationnel d’un porteur de projet et sa contribution à l’acquisition des moyens financiers, des informations et du support social. Ceci revient à ce que l’entrepreneur, dès qu’il se trouve emporté par le désir d’assurer la survie et le rayonnement de son projet, il se trouve le plus souvent confronté à un handicap de financier mitigé à un manque d’informations et de support social en provenance de ses collaborateurs. Or, toujours est-il que le capital social entrepreneurial en soi suscite une polémique et une interrogation sur les facteurs qui propulsent son développement. Dans cette perspective, nous proposons de centrer notre réflexion sur les compétences sociales afin d’apporter un éclairage à la manière dont se forme le capital relationnel du porteur d’un projet. Dans le même sillage d’idées, nous soulignons les influences que ces habiletés sont susceptibles d’exercer autant sur la mobilisation des moyens nécessaires que sur l’extension du capital relationnel de l’entrepreneur. Une investigation qualitative conduite sur une dizaine de porteurs de projets tunisiens a été effectuée pour tester ces propos, via une reconsidération des catégories d’aptitudes socio-relationnelles les plus saillantes.

  9. Influence de l'érythropoïétine recombinante humaine sur les fonctions cardiovasculaire et rénale chez le rat présentant une dysfonction endothéliale : effets des interactions avec l'exercice chronique

    OpenAIRE

    Meziri , Fayçal

    2011-01-01

    The chronic administration of rHuEPO can engender side effects. An increase of the hematocritinduced by rHuEPO, by increasing the erythrocytosis, the blood viscosity and the shear stress onvascular surface, can be responsible of arterial high blood pressure and arterial thrombosis. Thepresence of a normal endothelial function and nitric oxide (NO) can counter the noxious effectsof rHuEPO. On these bases, we studied the cardiovascular effects of a chronic administration ofrHuEPO in various fra...

  10. Ressource efficiency and ressource political aspects of the system electromobility. Work package 7 of the research program OPTUM. Optimization of the potentials for environmental relief of electric-powered vehicles; Ressourceneffizienz und ressourcenpolitische Aspekte des Systems Elektromobilitaet. Arbeitspaket 7 des Forschungsvorhabens OPTUM. Optimierung der Umweltentlastungspotenziale von Elektrofahrzeugen

    Energy Technology Data Exchange (ETDEWEB)

    Buchert, Matthias; Jenseit, Wolfgang; Dittrich, Stefanie; Hacker, Florian [Oeko-Institut e.V. - Institut fuer Angewandte Oekologie, Darmstadt (Germany); Schueler-Hainsch, Eckhard; Ruhland, Klaus; Knoefel, Sven [Daimler AG, Stuttgart (Germany); Goldmann, Daniel; Rasenack, Kai [Technische Univ. Clausthal, Clausthal-Zellerfeld (Germany); Treffer, Frank [Umicore, Hanau-Wolfgang (Germany)

    2011-10-28

    The development and successful implementation of the electric mobility is a key factor for a sustainable mobility. The Federal Government has passed the National Electromobility Development Plan on 19th August 2009. In the context of resource efficiency and resource-political aspects of the system electromobility the following sub-targets are addressed: (1) Identification of the main raw materials for electric-powered vehicles; (2) Determination of the quantitative demand for these raw materials by means of a scenario technique; (3) Investigation of the environmental impact of the production and processing of raw materials, comparison of the environmental impact with the environmental benefits due to the electromobility; (4) Comprehensive investigation of how the recycling of raw materials is feasible technically and economically; (5) Transparent display of available reserves of these raw materials and assessment of the extend of available resources; (6) Determination of the overall impact of the planned expansion of electromobility on the supply situation and the future price development of raw materials required; (7) Analysis of alternative technologies for single components for the reduction in demand of the required raw materials.

  11. Dizziness in older patients in general practice: away from diagnostic nihilism

    NARCIS (Netherlands)

    Dros, J.

    2013-01-01

    Bij ouderen met duizeligheid spelen vaak meerdere aandoeningen een rol, zoals cardiovasculaire of psychiatrische ziekten, problemen met het evenwichtsorgaan of bijwerkingen van geneesmiddelen. Duizeligheid bij ouderen is een veelvoorkomend probleem waarover relatief weinig bekend is. Op verzoek van

  12. Cholesterol, bile acid and triglyceride metabolism intertwined

    NARCIS (Netherlands)

    Schonewille, Marleen

    2016-01-01

    Hyperlipidemie wordt gekarakteriseerd door verhoogd plasma cholesterol en/of triglyceriden en sterk geassocieerd met het risico op cardiovasculaire aandoeningen. Dit proefschrift beschrijft onderzoek naar de regulatie van plasma cholesterol en triglyceriden concentraties en de achterliggende

  13. Etnische en sociaaleconomische verschillen bij hart- en vaatziekten.

    NARCIS (Netherlands)

    Vintges, M.M.O.; Brewster, L.M.; Dijk, L. van; Horikx, A.; Muijsenbergh, M.E.T.C. van den

    2013-01-01

    De prevalentie van cardiovasculaire risicofactoren varieert voor de verschillende etnische groepen in Nederland, evenals voor de verschillende inkomensgroepen. Mensen van Afrikaanse afkomst en uit zuidelijk Afrika hebben vaker hypertensie en ook een ernstigere vorm van hypertensie. Mensen van

  14. Original Paper Evaluation de la fonction rénale chez les patients ...

    African Journals Online (AJOL)

    Evaluation de la fonction rénale chez les patients atteints de maladie cardio vasculaire (MCV) : comparaison entre ... Mots clés : Cystatine C, créatinine, insuffisance rénale, débit de filtration glomérulaire, maladies cardiovasculaires. Evaluation of the ... L'insuffisance rénale chronique (IRC) et les maladies cardiovasculaires ...

  15. Contribution of stimulations for the optimization of quantitative electron probe micro analysis of heterogeneous catalysts; Apport de la simulation dans l'optimisation de l'analyse quantitative par microsonde electronique de catalyseurs heterogenes

    Energy Technology Data Exchange (ETDEWEB)

    Sorbier, L.

    2001-11-01

    Electron Probe Micro Analysis (EPMA) is frequently used to measure the local concentration of active elements in heterogeneous catalysts. However, when classical procedures are used, a significant deficit is observed both in local total concentration and mean total concentrations. A Monte Carlo program simulating measured intensities (characteristic lines and continuous background) has been written using PENELOPE routines. We have included in this program models taking into account the different physical phenomena likely to lead to the observed signal loss (insulating properties, roughness, porosity, energy loss at interfaces). Simulation results have shown that an important roughness (Ra>200 nm) was the only parameter apt to lead to a significant total signal loss. This led us to inquire into another origin to explain the signal loss observed on meso-porous samples. Measurements conducted on a meso-porous alumina confirmed that measuring aluminum, oxygen and carbon leads to a correct total of concentrations. Signal loss is thus explained by the contamination of the sample during its preparation, the components of the embedding resin diffusing into the porosity and reacting with the reactive surface of the catalyst support. In the case of macroporous catalysts, local roughness effect is very important. The simulations have shown the efficiency of the Peak to Background method to correct these local roughness effects. Measurements conducted on reforming and hydro-treating catalysts have led to a correct total concentration and confirmed the contribution of the Peak to Background method to achieve local quantitative measurement. (author)

  16. Effect of the coupling between electronic structure and crystalline structure on some properties of transition metals; Couplage entre structure electronique et structure cristalline: effet sur quelques proprietes des metaux de transition

    Energy Technology Data Exchange (ETDEWEB)

    Nastar, M

    1994-10-14

    The elastic constants, energetic stabilities and vacancy formation energies in transition metals are calculated within a Tight Binding model. In order to outline the effect of the electronic structure, these properties are represented as functions of band filling. The variation of the shear elastic constants of hexagonal close packed (HCP), body centered cubic (BCC) and face centered cubic (FCC) structures, is in contrast with the roughly parabolic behavior of bulk modulus. The general trends are in very good agreement with available experimental and `ab initio` data. The vacancy formation energy in the BCC structure shows strong deviations from bell shape behavior with a maximum corresponding approximately to the band filling of group 6. This band filling effect contributes to the noticeable decrease of the self diffusion rate between group 4 and group 6. We demonstrate that the abrupt increase of the C` elastic constant, the NT{sub 1} (0.-1.1) phonon frequency, the energy differences between BCC and HCP and between FCC and HCP as well as the vacancy formation energy, that occurs when going from Zr to Mo, is related to the presence of a pseudo-gap in the density of states of the BCC structure. Using the recursion method, we show that the general trends of these properties are correctly reproduced when considering only a few moments of the density of states (about 6). On the other hand, details such as the elastic constant singularities, are displayed only with an exact calculation of the density of states. (Author). 173 refs., 84 figs., 5 tabs.

  17. Relaxation and excitation electronic processes in dielectrics irradiated by ultrafast IR and VUV pulses; Processus electroniques d'excitation et de relaxation dans les solides dielectriques excites par des impulsions IR et XUV ultracourtes

    Energy Technology Data Exchange (ETDEWEB)

    Gaudin, J

    2005-11-15

    We studied excitation and relaxation of electrons involved during interaction of visible and VUV femtosecond pulses with dielectrics. The generated population of hot electrons, having energy of few eV to few tens of eV above the bottom of the conduction band, is responsible of phenomena ranging to defect creation to optical breakdown. Owing to two techniques: photoemission and transient photoconductivity we improve the understanding of the The first photoemission experiments deal with dielectrics irradiated by 30 fs IR pulses. The photoemission spectra measured show a large population of electrons which energy rise up to 40 eV. We interpret this result in terms of a new absorption process: direct multi-photons inter-branch transitions. The 2. type of photoemission experiments are time resolved 'pump/probe' investigation. We study the relaxation of electrons excited by a VUV pulses. We used the high order harmonics (HOH) as light sources. We found surprisingly long decay time in the range of ps timescale. Last type of experiments is photoconductivity studies of diamond samples. Using HOH as light source we measure the displacement current induced by excited electrons in the conduction band. Those electrons relax mainly by impact ionisation creating secondary electrons. Hence by probing the number of electrons we were able to measure the efficiency of these relaxation processes. We observe a diminution of this efficiency when the energy of exciting photons is above 20 eV. Owing to Monte-Carlo simulation we interpret this result in terms of band structure effect. (author)

  18. Development of a compact electronic dosemeter from CMOS sensor for radon measurement; Developpement d'un dosimetre electronique compact a base de capteurs CMOS pour la mesure du radon

    Energy Technology Data Exchange (ETDEWEB)

    Higueret, St

    2007-12-15

    Radon detection is a long-standing challenge in the field of radioprotection, and the IPHC Institute of Strasbourg has pushed for the development of a fully electronic device, portable and really standalone. Our first prototype of CMOS system-on-chip is presented, together with efficiency tests and the corresponding physics simulations (TRIM, GEANT IV). We describe several electronic boards which have been developed for various kinds of tests, firstly passive detection of {alpha}-particles from gaseous {sup 222}Rn in a large spectrum of activity concentrations. In a second stage, active collection of the daughter isotopes {sup 218}Po and {sup 214}Po was performed: these elements, appearing as attached on the aerosols present in air, are an important contribution to internal {alpha}-irradiation. The final electronic system, of only 10 cm size, includes four independent chips to ensure simultaneous detection of radon gas and its aerosols. An excellent linearity has been measured up to 80 kBq.m{sup -3} on the BACCARA bench of the IRSN at Saclay. A new generation chip is also studied. (author)

  19. Study of electronic field emission from large surfaces under static operating conditions and hyper-frequency; Etude de l'emision electronique par effet de champ sur des surfaces larges en regime statique et hyperfrequence

    Energy Technology Data Exchange (ETDEWEB)

    Luong, M

    1997-09-01

    The enhanced electronic field emission from large area metallic surfaces lowers performances of industrial devices that have to sustain high electric field under vacuum. Despite of numerous investigations in the past, the mechanisms of such an emission have never been well clarified. Recently, research in our laboratory has pointed out the importance played by conducting sites (particles and protrusions). A refined geometrical model, called superposed protrusions model has been proposed to explain the enhanced emission by local field enhancement. As a logical continuation, the present work aims at testing this model and, in the same time, investigating the means to suppress the emission where it is undesirable. Thus, we have showed: the cause of current fluctuations in a continuous field regime (DC), the identity of emission characteristics ({beta}, A{sub e}) in both radiofrequency (RF) and DC regimes, the effectiveness of a thermal treatment by extern high density electronic bombardment, the effectiveness of a mechanical treatment by high pressure rinsing with ultra pure water, the mechanisms and limits of an in situ RF processing. Furthermore, the electronic emission from insulating particles has also been studied concurrently with a spectral analysis of the associated luminous emission. Finally, the refined geometrical model for conducting sites is reinforced while another model is proposed for some insulating sites. Several emission suppressing treatments has been explored and validated. At last, the characteristic of a RF pulsed field emitted electron beam has been checked for the first time as a possible application of such a field emission. (author)

  20. Theoretical study of the electronic structure of f-element complexes by quantum chemical methods; Analyse de la structure electronique des complexes contenant des elements F par des methodes de la chimie quantique

    Energy Technology Data Exchange (ETDEWEB)

    Vetere, V

    2002-09-15

    This thesis is related to comparative studies of the chemical properties of molecular complexes containing lanthanide or actinide trivalent cations, in the context of the nuclear waste disposal. More precisely, our aim was a quantum chemical analysis of the metal-ligand bonding in such species. Various theoretical approaches were compared, for the inclusion of correlation (density functional theory, multiconfigurational methods) and of relativistic effects (relativistic scalar and 2-component Hamiltonians, relativistic pseudopotentials). The performance of these methods were checked by comparing computed structural properties to published experimental data, on small model systems: lanthanide and actinide tri-halides and on X{sub 3}M-L species (X=F, Cl; M=La, Nd, U; L = NH{sub 3}, acetonitrile, CO). We have thus shown the good performance of density functionals combined with a quasi-relativistic method, as well as of gradient-corrected functionals associated with relativistic pseudopotentials. In contrast, functionals including some part of exact exchange are less reliable to reproduce experimental trends, and we have given a possible explanation for this result . Then, a detailed analysis of the bonding has allowed us to interpret the discrepancies observed in the structural properties of uranium and lanthanides complexes, based on a covalent contribution to the bonding, in the case of uranium(III), which does not exist in the lanthanide(III) homologues. Finally, we have examined more sizeable systems, closer to experimental species, to analyse the influence of the coordination number, of the counter-ions and of the oxidation state of uranium, on the metal-ligand bonding. (author)

  1. Contribution to a quantitative assessment model for reliability-based metrics of electronic and programmable safety-related functions; Contribution a un modele d'evaluation quantitative des performances fiabilistes de fonctions electroniques et programmables dediees a la securite

    Energy Technology Data Exchange (ETDEWEB)

    Hamidi, K

    2005-10-15

    The use of fault-tolerant EP architectures has induced growing constraints, whose influence on reliability-based performance metrics is no more negligible. To face up the growing influence of simultaneous failure, this thesis proposes, for safety-related functions, a new-trend assessment method of reliability, based on a better taking into account of time-aspect. This report introduces the concept of information and uses it to interpret the failure modes of safety-related function as the direct result of the initiation and propagation of erroneous information until the actuator-level. The main idea is to distinguish the apparition and disappearance of erroneous states, which could be defined as intrinsically dependent of HW-characteristic and maintenance policies, and their possible activation, constrained through architectural choices, leading to the failure of safety-related function. This approach is based on a low level on deterministic SED models of the architecture and use non homogeneous Markov chains to depict the time-evolution of probabilities of errors. (author)

  2. Contribution of stimulations for the optimization of quantitative electron probe micro analysis of heterogeneous catalysts; Apport de la simulation dans l'optimisation de l'analyse quantitative par microsonde electronique de catalyseurs heterogenes

    Energy Technology Data Exchange (ETDEWEB)

    Sorbier, L

    2001-11-01

    Electron Probe Micro Analysis (EPMA) is frequently used to measure the local concentration of active elements in heterogeneous catalysts. However, when classical procedures are used, a significant deficit is observed both in local total concentration and mean total concentrations. A Monte Carlo program simulating measured intensities (characteristic lines and continuous background) has been written using PENELOPE routines. We have included in this program models taking into account the different physical phenomena likely to lead to the observed signal loss (insulating properties, roughness, porosity, energy loss at interfaces). Simulation results have shown that an important roughness (Ra>200 nm) was the only parameter apt to lead to a significant total signal loss. This led us to inquire into another origin to explain the signal loss observed on meso-porous samples. Measurements conducted on a meso-porous alumina confirmed that measuring aluminum, oxygen and carbon leads to a correct total of concentrations. Signal loss is thus explained by the contamination of the sample during its preparation, the components of the embedding resin diffusing into the porosity and reacting with the reactive surface of the catalyst support. In the case of macroporous catalysts, local roughness effect is very important. The simulations have shown the efficiency of the Peak to Background method to correct these local roughness effects. Measurements conducted on reforming and hydro-treating catalysts have led to a correct total concentration and confirmed the contribution of the Peak to Background method to achieve local quantitative measurement. (author)

  3. Application of new fast-electronic techniques to the determination of the exact moment of particle detection; Application des techniques nouvelles de l'electronique rapide a la determination de l'instant precis de detection d'une particule

    Energy Technology Data Exchange (ETDEWEB)

    Hesse, M [Commissariat a l' Energie Atomique, Grenoble (France). Centre d' Etudes Nucleaires

    1965-06-01

    Fluctuations in the time response of photomultipliers employed in scintillation counting are studied and experimentally checked. Statistical measurements of the output pulses show that the relative variance of the time fluctuations is minimum for the portion located around the bending point of the leading edge. A shaping circuit using this property is described. Experimental results are given, showing an improvement of the resolving time. (author) [French] Les fluctuations de la reponse temporelle des photomultiplicateurs, utilises dans les detecteurs a scintillations, sont etudiees et mesurees experimentalement. L'etude statistique des signaux de sortie montre que les fluctuations en temps presentent une variance relative minimale pour la region situee autour du point d'inflexion du front de montee. Un circuit de mise en forme utilisant cette propriete est decrit. Des resultats experimentaux sont donnes; ils montrent une amelioration sensible du pouvoir de resolution. (auteur)

  4. Modeling of polarization phenomena due to RF sheaths and electron beams in magnetized plasma; Modelisation de phenomenes de polarisation par des gaines rf et des faisceaux electroniques dans un plasma magnetise

    Energy Technology Data Exchange (ETDEWEB)

    Faudot, E

    2005-07-01

    This work investigates the problematic of hot spots induced by accelerated particle fluxes in tokamaks. It is shown that the polarization due to sheaths in the edge plasma in which an electron beam at a high level of energy is injected, can reach several hundreds volts and thus extend the deposition area. The notion of obstructed sheath is introduced and explains the acceleration of energy deposition by the decreasing of the sheath potential. Then, a 2-dimensional fluid modeling of flux tubes in front of ICRF antennae allows us to calculate the rectified potentials taking into account RF polarization currents transverse to magnetic field lines. The 2-dimensional fluid code designed validates the analytical results which show that the DC rectified potential is 50% greater with polarization currents than without. Finally, the simultaneous application of an electron beam and a RF potential reveals that the potentials due to each phenomenon are additives when RF potential is much greater than beam polarization. The density depletion of polarized flux tubes in 2-dimensional PIC (particles in cells) simulations is characterized but not yet explained. (author)

  5. Dimensioning of a two-phase loop for the study of the cooling of power electronics components; Dimensionnement d`une boucle diphasique pour l`etude du refroidissement des composants d`electronique de puissance

    Energy Technology Data Exchange (ETDEWEB)

    Bricard, A [CEA Centre d` Etudes Nucleaires de Grenoble, 38 (France). STTGRETh

    1997-12-31

    After having chosen between different cooling solutions for a given power electronics component, the dimensioning of a two-phase forced convection loop is described. The power electronics component is a 12 x 12 mm silicon pellet which can dissipate up to 400 W/cm{sup 2} heat fluxes. In a first step, the minimum size of channels is determined according to fluid characteristics, pressure drop and critical fluxes. In a second step, the coupled dimensioning of both the evaporator and the condenser is determined for different values of pipes diameter and mass flow rates. (J.S.) 8 refs.

  6. The gaseous emission of polymers under swift heavy ion irradiation: effect of the electronic stopping power; L'emission gazeuse des polymeres aliphatiques sous irradiation: effet du pouvoir d'arret electronique

    Energy Technology Data Exchange (ETDEWEB)

    Picq, V

    2000-07-01

    This thesis contributes to a better understanding of the damaging processes, which occur in polymers under swift heavy ion irradiation. The present study is exclusively devoted to the influence of the electronic stopping power, (dE/dx)e, on the molecular emission under irradiation. The irradiated polymers are polyethylene, polypropylene and poly-butene. The (dE/dx)e of the projectiles used varies from 3.5*10{sup -3} MeV.mg{sup -1}.cm{sup 2} (electron) to 39 MeV.mg{sup -1}.cm{sup 2} ({sup 58}Ni). We used two different experimental approaches in order to identify the nature of the emitted gases: mass spectrometry and infrared spectroscopy. The first technique is non selective, therefore, we could detect the emission of H{sub 2} and heavy molecules; it also gives information on the diffusion kinetics of the molecules formed. The use of infrared spectroscopy for this kind of analysis is new and the technique was developed at the laboratory. It enables us to identify, without any ambiguity, molecules with up to three carbon atoms. The experimental spectra are analysed by using reference spectra of pure gases, measured in our laboratory. We have quantified precisely each identified gas, and we have followed the evolution of the radiochemical yields with increasing (dE/dx)e. The results, obtained at different (dE/dx)e, inform us on the different mechanisms of gas molecules formation, for example the side group departure and, at high (dE/dx)e, the fragmentation of the main chain which is due to multiple ionisation of the macromolecule. (author)

  7. Electron emission following collisions between multi-charged ions and D{sub 2} molecules; Etude de l'emission electronique induite par impact d'ion multicharge sur la molecule D{sub 2}

    Energy Technology Data Exchange (ETDEWEB)

    Laurent, G

    2004-05-15

    Dissociative ionisation mechanisms induced in collisions involving a highly charged ion (S{sup 15+}, 13.6 MeV/u) and a molecular deuterium target, have been studied through momentum vector correlations of both the D{sup +} fragments and the electrons produced. An experimental apparatus has been developed in order to detect in coincidence all the charged particles produced during the collision. The measurement of their momentum vectors, which allows one to determine both their kinetic energy and direction of emission with respect to the projectile one, combines Time of Flight, Position Sensitive Detection, and multi-coincidence techniques. The correlation of the fragment and electron kinetic energies enables not only to determine branching ratios between the dissociative ionisation pathways, but also to separate unambiguously kinetic energy distributions of fragments associated to each process. Finally, the angular distributions of ejected electrons, as a function of the orientation of the molecular axis with respect to the projectile direction, are deduced from the spatial correlation. Measurements are compared to theoretical angular distributions obtained using the CDW-EIS (Continuum Distorted Wave-Eikonal Initial State) method. (author)

  8. Contribution to a quantitative assessment model for reliability-based metrics of electronic and programmable safety-related functions; Contribution a un modele d'evaluation quantitative des performances fiabilistes de fonctions electroniques et programmables dediees a la securite

    Energy Technology Data Exchange (ETDEWEB)

    Hamidi, K

    2005-10-15

    The use of fault-tolerant EP architectures has induced growing constraints, whose influence on reliability-based performance metrics is no more negligible. To face up the growing influence of simultaneous failure, this thesis proposes, for safety-related functions, a new-trend assessment method of reliability, based on a better taking into account of time-aspect. This report introduces the concept of information and uses it to interpret the failure modes of safety-related function as the direct result of the initiation and propagation of erroneous information until the actuator-level. The main idea is to distinguish the apparition and disappearance of erroneous states, which could be defined as intrinsically dependent of HW-characteristic and maintenance policies, and their possible activation, constrained through architectural choices, leading to the failure of safety-related function. This approach is based on a low level on deterministic SED models of the architecture and use non homogeneous Markov chains to depict the time-evolution of probabilities of errors. (author)

  9. Evolution of the use of the portal imaging device: prospective study over three periods; Evolution des concepts d'utilisation de l'imagerie electronique: etude prospective sur trois periodes

    Energy Technology Data Exchange (ETDEWEB)

    Barillot, I.; Maingon, P.; Truc, G.; D' Hombres, A.; Steyer, B.; Naudy, S.; Horiot, J.C. [Centre de Lutte Contre le Cancer Georges-Francois-Leclerc, 21 - Dijon (France)

    2000-02-01

    From 1990, as part of the quality assurance research programs, the radiotherapy department of the G. F. Leclerc Centre of Dijon used EPID system in a prospective fashion. During the first of the three periods (PER 1:1990-1993), the study consisted of analysis criteria determination, software efficiency improvement and a selection of patients who could benefit from the method. Eight hundred and forty-five images of 40 patients were analysed qualitatively and quantitatively. Two verifications per week were planned, and the action level for correction was 10 mm. Head and neck images also displayed in 'cinema' presentation for internal movements analysis. From 1994 to 1995 (PER 2), off-line procedure (OLP) based upon early correction of the systemic error and the rules calculated from our previous experience were tested for checking the brain, head and neck (LOC 1: 396 images) and many of the pelvic irradiations (LOC 2: 260 images). A double-exposure procedure and/or movie loop presentation was reserved for other patients. During the last period (PER 3: 1996-1997), the OLP procedure was routinely performed in 54 patients (images: 321 LOC 1, 680 LOC 2). LOC 1: deviations of < 3 mm increased from 75.5% during PER 1 to 81 % during PER 2 to 83% during PER 3. Conversely, deviations of 3-5 mm dropped from 19.5 to 13%, while deviations of more than 5 mm remained stable, around 5%. The actual standard error of the mean deviation observed was 2 mm. LOC 2: deviations of < 5 mm were observed in 81% of the cases during PER 1 and in 91% during PER 3 (89.5% in PER 2). These good results led to a decrease in deviation of 5 to 7 mm (11 to 6 %) and also to a significant drop in deviations of more than 7 mm, 8 to 3% respectively. The actual precision obtained was 2.5 mm {+-} SD. (author)

  10. Study of electronic field emission from large surfaces under static operating conditions and hyper-frequency; Etude de l'emision electronique par effet de champ sur des surfaces larges en regime statique et hyperfrequence

    Energy Technology Data Exchange (ETDEWEB)

    Luong, M

    1997-09-01

    The enhanced electronic field emission from large area metallic surfaces lowers performances of industrial devices that have to sustain high electric field under vacuum. Despite of numerous investigations in the past, the mechanisms of such an emission have never been well clarified. Recently, research in our laboratory has pointed out the importance played by conducting sites (particles and protrusions). A refined geometrical model, called superposed protrusions model has been proposed to explain the enhanced emission by local field enhancement. As a logical continuation, the present work aims at testing this model and, in the same time, investigating the means to suppress the emission where it is undesirable. Thus, we have showed: the cause of current fluctuations in a continuous field regime (DC), the identity of emission characteristics ({beta}, A{sub e}) in both radiofrequency (RF) and DC regimes, the effectiveness of a thermal treatment by extern high density electronic bombardment, the effectiveness of a mechanical treatment by high pressure rinsing with ultra pure water, the mechanisms and limits of an in situ RF processing. Furthermore, the electronic emission from insulating particles has also been studied concurrently with a spectral analysis of the associated luminous emission. Finally, the refined geometrical model for conducting sites is reinforced while another model is proposed for some insulating sites. Several emission suppressing treatments has been explored and validated. At last, the characteristic of a RF pulsed field emitted electron beam has been checked for the first time as a possible application of such a field emission. (author)

  11. Supra-transmission and bistability in nonlinear media with a photonic and electronic forbidden band gap; Supratransmission et bistabilite nonlineaire dans les milieux a bandes interdites photoniques et electroniques

    Energy Technology Data Exchange (ETDEWEB)

    Chevriaux, D

    2007-06-15

    We study wave scattering in different nonlinear media possessing a natural forbidden band gap. In particular, we show the existence of a bistable behavior in media governed by the sine-Gordon equation (short pendular chain, Josephson junction array, quantum Hall bilayer), or the nonlinear Schroedinger equation (Kerr and Bragg media), in discrete and continuous models. These different media are submitted to periodic boundary conditions with a frequency in the forbidden band gap and an amplitude that determines their stability states. Indeed, for a sufficient amplitude (supra-transmission), the medium switches from reflector to transmitter, hence allowing the output signal to jump from evanescent to large values. We give a complete analytical description of the bistability that allows to understand the different stationary states observed and to predict the switch of one state to the other. (author)

  12. Non-inductive plasmas studies by injection of electron cyclotron waves in the Tore Supra tokamak; Etudes des plasmas non-inductifs par injection d'ondes a la frequence cyclotronique electronique dans le tokamak Tore Supra

    Energy Technology Data Exchange (ETDEWEB)

    Turco, F

    2008-06-15

    In this work we addressed the issue of the phenomena typical of the non-inductive discharges in the Tore Supra tokamak, probed by means of localised perturbations of the current density profile, performed by electron cyclotron (EC) waves. In order to correctly utilize the current density profile, reconstructed by means of the CRONOS code we performed a sensitivity study on the code results. Concerning the MHD regimes we have shown that a dynamic evolution of the safety factor q which tends to shrink its profile appears to be the cause of the triggering of such regimes. From the operational point of view, deposing the EC current, generated in the same direction of the plasma current, outside the q{sub min} position results hazardous because it causes a rise in q{sub 0} and consequently the shrinking of the q profile which triggers the MHD regimes. On the contrary, the EC counter-current scans show that a very central deposition ({rho}(ECCD) < 0.1) lead almost certainly to an MHD regime, while a more external countercurrent generation has generally the quality of creating internal transport barriers (ITBs). The phenomenon of non-linear temperature oscillations (the O-regime) has also been addressed, to provide an analytical description as well as from the experimental point of view, concerning the triggering and canceling of the oscillating phases. By constructing a non-linear predator-prey system with noise, solved on two regions of space coupled by a diffusion term, we could reproduce the experimental temperature oscillations: this study allowed us to confirm that the oscillatory phenomenon is the manifestation of a Lotka-Volterra like coupling between j and T{sub e}. The experimental analysis led to the identification of the mechanism at the origin of the triggering and canceling of the O-regime in presence of a perturbation in a specific shape of magnetic shear perturbation. These results have been reproduced by the simulations preformed with the integrated modelling code CRONOS. Finally, observations based on an extended database allowed us to document the existence of a tight relation between q{sub 0} passing through low order rational values and the formation of an ITB. (author)

  13. Electronic structure of Pu-Ce(-Ga) and Pu-Am(-Ga) alloys, stabilized in the {delta} phase; Structure electronique d'alliages Pu-Ce(-Ga) et Pu-Am(-Ga) stabilises en phase {delta}

    Energy Technology Data Exchange (ETDEWEB)

    Dormeval, M

    2001-09-01

    The behaviour of {delta}-plutonium, stable between 319 and 451 deg C, exhibits numerous singularities which are still a mystery for both physicists and metallurgists. This is due to its complex electronic structure, and in particular to the 5f electrons, which are at the edge between localization and delocalization. The stability domain of the {delta} phase can be extended down to room temperature by alloying with so called 'deltagen atoms' such as gallium (Ga), aluminum (A1), cerium (Ce) or americium (Am). The present work deals, one the one hand, with the influence of cerium and americium solutes regarding the localization of the 5f electrons of {delta}-plutonium, in binary Pu-Ce and Pu-Am alloys. On the other hand, the effect of two different deltagen solutes, simultaneously present, on the stability of the {delta} phase has been studied in ternary Pu-Am-Ga and Pu-Ce-Ga alloys. The electronic structure being strongly related to the crystalline organization, characterization methods such as X-Ray diffraction and EXAFS measurements were used together with electrical resistivity and magnetic susceptibility experiments. These showed that the roles of cerium and americium, supposed to be similar at the beginning of this investigation, are actually very different. Moreover, the additive effect of cerium and gallium, and, americium and gallium, has been demonstrated. Studying plutonium alloys, which are radioactive, also means following their evolution in time. The characteristics of the alloys have then been followed which allowed to detect, in Pu-Ce(-Ga) alloys, a destabilization of the {delta} phase and, to observe, in Pu-Am(-Ga) alloys, the influence of self-irradiation defects on the magnetic response. (author)

  14. Fabrication, characterization and radiation damage stability of hollandite based ceramics devoted to radioactive immobilisation; Synthese, caracterisation et etude du comportement sous irradiation electronique de matrices de type hollandite destinees au confinement du cesium radioactif

    Energy Technology Data Exchange (ETDEWEB)

    Aubin-Chevaldonnet, V. [CEA Valrho, Dir. de l' Energie Nucleaire (DEN/DETCD/SCDV), Dept. d' Etudes du Traitement et du Conditionnement des Dechets, Service de Conditionnement des Dechets et Vitrification, 30 - Marcoule (France)

    2004-11-01

    Research on treating specifically the long-lived and high level nuclear wastes, notably cesium, is currently carried out in France. Cesium immobilization in host matrices of high chemical durability constitutes the favoured option. Hollandite matrix is a good candidate because of its high cesium incorporation ability and its excellent chemical stability. During this study, different compositions of hollandite ceramics Ba{sub x}Cs{sub y}C{sub z}Ti{sub 8-z}O{sub 16} (C = Al{sup 3+}, Cr{sup 3+}, Ga{sup 3+}, Fe{sup 3+}, Mg{sup 2+}, Sc{sup 3+}), synthesized by oxide route, were characterized in terms of structure, microstructure and physical and chemical properties. Iron ions seems to be the most suitable of the studied C cations to get high-performance hollandites. The stability of these ceramics under external electron irradiation, simulating the {beta} particles emitted by radioactive cesium, were also estimated, at the macroscopic and atomic scale. The point defects creation and their thermal stability were followed by electron paramagnetic resonance. (author)

  15. Dimensioning of a two-phase loop for the study of the cooling of power electronics components; Dimensionnement d`une boucle diphasique pour l`etude du refroidissement des composants d`electronique de puissance

    Energy Technology Data Exchange (ETDEWEB)

    Bricard, A. [CEA Centre d`Etudes Nucleaires de Grenoble, 38 (France). STTGRETh

    1996-12-31

    After having chosen between different cooling solutions for a given power electronics component, the dimensioning of a two-phase forced convection loop is described. The power electronics component is a 12 x 12 mm silicon pellet which can dissipate up to 400 W/cm{sup 2} heat fluxes. In a first step, the minimum size of channels is determined according to fluid characteristics, pressure drop and critical fluxes. In a second step, the coupled dimensioning of both the evaporator and the condenser is determined for different values of pipes diameter and mass flow rates. (J.S.) 8 refs.

  16. Tokamak electron heat transport by direct numerical simulation of small scale turbulence; Transport de chaleur electronique dans un tokamak par simulation numerique directe d'une turbulence de petite echelle

    Energy Technology Data Exchange (ETDEWEB)

    Labit, B

    2002-10-01

    In a fusion machine, understanding plasma turbulence, which causes a degradation of the measured energy confinement time, would constitute a major progress in this field. In tokamaks, the measured ion and electron thermal conductivities are of comparable magnitude. The possible sources of turbulence are the temperature and density gradients occurring in a fusion plasma. Whereas the heat losses in the ion channel are reasonably well understood, the origin of the electron losses is more uncertain. In addition to the radial velocity associated to the fluctuations of the electric field, electrons are more affected than ions by the magnetic field fluctuations. In experiments, the confinement time can be conveniently expressed in terms of dimensionless parameters. Although still somewhat too imprecise, these scaling laws exhibit strong dependencies on the normalized pressure {beta} or the normalized Larmor radius, {rho}{sub *}. The present thesis assesses whether a tridimensional, electromagnetic, nonlinear fluid model of plasma turbulence driven by a specific instability can reproduce the dependence of the experimental electron heat losses on the dimensionless parameters {beta} and {rho}{sub *}. The investigated interchange instability is the Electron Temperature Gradient driven one (ETG). The model is built by using the set of Braginskii equations. The developed simulation code is global in the sense that a fixed heat flux is imposed at the inner boundary, leaving the gradients free to evolve. From the nonlinear simulations, we have put in light three characteristics for the ETG turbulence: the turbulent transport is essentially electrostatic; the potential and pressure fluctuations form radially elongated cells called streamers; the transport level is very low compared to the experimental values. The thermal transport dependence study has shown a very small role of the normalized pressure, which is in contradiction with the Ohkama's formula. On the other hand, the crucial role of the electron normalized Larmor has been emphasized: the confinement time is inverse proportional to this parameter. Finally, the low dependence of turbulent transport with the magnetic shear and the inverse aspect ratio is also reported. Although the transport level observed in the simulations is low compared to the experiments, we have tried a direct confrontation with Tore Supra results. This tokamak is well designed to study the electron heat transport. Keeping most of the parameters from a well referenced Tore Supra shot, the nonlinear simulation gives a threshold quite close to the experimental one. The observed turbulent conductivity is a factor fifty lower than the experimental one. An important parameter can not be matched: the normalized Larmor radius, {rho}{sub *}. This limitation has to be overcome in order to confirm this results. Finally, a rigorous confrontation between this result and gyrokinetic simulations has to conclude that the ETG instability cannot describe electron heat loses in tokamaks. (author)

  17. Characteristics of transitory multi-charged molecular ions produced by an intense femtosecond laser impulse; Etats electroniques des ions moleculaires multicharges transitoires produits par une impulsion laser femtoseconde intense

    Energy Technology Data Exchange (ETDEWEB)

    Quaglia, L

    2001-12-01

    The study of the molecular multi-ionization is narrowly linked to the dynamics of excitation and fragmentation for which the experimental observables rest on the characteristics of the fragmentation products, these characteristics are: intern energy, kinetic energy and charge states. The first chapter sets the problem. The second chapter presents the experimental tools used and developed in this work, the technologies of the detection of ions or of fluorescence are also described. The chapter 3 gathers the theoretical aspects: quantum chemistry and CASSCF (complete active space self consistent field) methods have been used to compute the potential energy curves of multi-charged ions, the two-dimensional hydrodynamic model derived from the Thomas-Fermi model is introduced to tackle the molecular re-orientation. The chapter 4 presents the experimental study of highly excited states by using fluorescence detection methods. The chapter 5 is dedicated to the study of low excited states by measuring kinetic energy spectra and by comparison with potential energy curves of molecular multi-charged ions. The chapter 6 presents experiments with 2 impulses and the results given by the Thomas-Fermi model applied to the re-orientation of the N{sub 2}O molecule. (A.C.)

  18. Simulated annealing method for electronic circuits design: adaptation and comparison with other optimization methods; La methode du recuit simule pour la conception des circuits electroniques: adaptation et comparaison avec d`autres methodes d`optimisation

    Energy Technology Data Exchange (ETDEWEB)

    Berthiau, G

    1995-10-01

    The circuit design problem consists in determining acceptable parameter values (resistors, capacitors, transistors geometries ...) which allow the circuit to meet various user given operational criteria (DC consumption, AC bandwidth, transient times ...). This task is equivalent to a multidimensional and/or multi objective optimization problem: n-variables functions have to be minimized in an hyper-rectangular domain ; equality constraints can be eventually specified. A similar problem consists in fitting component models. In this way, the optimization variables are the model parameters and one aims at minimizing a cost function built on the error between the model response and the data measured on the component. The chosen optimization method for this kind of problem is the simulated annealing method. This method, provided by the combinatorial optimization domain, has been adapted and compared with other global optimization methods for the continuous variables problems. An efficient strategy of variables discretization and a set of complementary stopping criteria have been proposed. The different parameters of the method have been adjusted with analytical functions of which minima are known, classically used in the literature. Our simulated annealing algorithm has been coupled with an open electrical simulator SPICE-PAC of which the modular structure allows the chaining of simulations required by the circuit optimization process. We proposed, for high-dimensional problems, a partitioning technique which ensures proportionality between CPU-time and variables number. To compare our method with others, we have adapted three other methods coming from combinatorial optimization domain - the threshold method, a genetic algorithm and the Tabu search method - The tests have been performed on the same set of test functions and the results allow a first comparison between these methods applied to continuous optimization variables. (Abstract Truncated)

  19. Study of hydrogenated amorphous silicon devices under intense electric field: application to nuclear detection; Etude de dispositifs electroniques en silicium amorphe hydrogene sous fort champ electrique: application a la detection nucleaire

    Energy Technology Data Exchange (ETDEWEB)

    Ilie, A. [CEA Centre d`Etudes de Saclay, 91 - Gif-sur-Yvette (France). Direction des Technologies Avancees]|[Paris-11 Univ., 91 - Orsay (France)

    1996-12-31

    The goal of this work was the study, development and optimization of hydrogenated amorphous silicon (a-Si:H) devices for use in detection of ionizing radiation. Thick p-i-n devices, capable of withstanding large electric fields (up to 10{sup 6} V/cm) with small currents (nA/cm{sup 2}), were developed. To decrease fabrication time, films were made using the `He diluted` PECVD process and compared to standard a-Si:H films. Aspects connected to specific detector applications as well as to the fundamental physics of a-Si:H were considered: the internal electric field technique, in which the depletion charge was measured as a function of the applied bias voltage; study of the leakage current of p-i-n devices permitted us to demonstrate different regimes: depletion, field-enhanced thermal generation and electronic injection across the p layer. The effect of the electric field on the thermal generation of the carriers was studied considering the Poole-Frenkel and tunneling mechanisms. A model was developed taking under consideration the statistics of the correlated states and electron-phonon coupling. The results suggest that mechanisms not included in the `standard model` of a Si:h need to be considered, such as defect relaxation, a filed-dependent mobility edge etc...; a new metastable phenomenon, induced by prolonged exposure to a strong electric field, was observed and studied. It is characterized by marked decrease of the leakage current and the detector noise, and increase in the breakdown voltage, as well as an improvement of carrier collection efficiency. This forming process appears to be principally due to an activation of the dopants in the p layer; finally, the capacity of thick p-i-n a Si:H devices to detect ionizing radiation has been evaluated. We show that it is possible, with 20-50 micron thick p-i-n devices, to detect the full spectrum of alpha and beta particles. With an appropriate converter, neutron detection then becomes possible. (author). 137 refs.

  20. Study of thermodynamics and electronics properties of hybrids of substituted Haucke compounds; Contribution a l'etude des proprietes thermodynamiques et electroniques d'hydrures de composes de Haucke substitues

    Energy Technology Data Exchange (ETDEWEB)

    Crivello, J.C

    2005-06-15

    This manuscript presents a combined experimental and theoretical contribution to the study of the substituted Haucke phase AB5. These compounds can reversibly absorb hydrogen under conditions of pressure and temperature satisfactory for many technological applications including hydrogen storage. The thermodynamic characterization of the solid-gas reaction was carried out for mono and poly-substituted compounds. In the respect of good conditions of growth (decomposition) of the hydride phase, we sought to determine the thermodynamic trajectories allowed during some various transformations. The experimental results showed that the rate of transformation and the hierarchy of the return-points memory are the only parameters allowing to draw a general law related to the irreversible character of hysteresis. These systems evolve in 'static' mode, independent of the time and whatever the nature of host materials. Moreover, the effect of substitution elements on electronic properties has been studied using ab initio band structure calculations for the ANi{sub 5} (A=La, Y, Ca) and LaNi{sub 5-x}M{sub x} compounds, where M is an element of the type s-p (Al, Si, Ge, Sn), of type s (Cu), or a transition metal (Mn, Fe, Co). While dissociating the structural effects, the role of the chemical interaction with hydrogen was analyzed. These results made it possible to identify the factors which control the stability of the hydrides and their maximum absorption capacity. The bulk moduli of these materials were calculated and their variation was discussed in relation to the properties of hydrogen absorption. (author)

  1. One-photon two-electron processes in helium close to the double ionization threshold; Diexcitation electronique de l'helium par un photon au voisinage du seuil de double ionisation

    Energy Technology Data Exchange (ETDEWEB)

    Bouri, C

    2007-04-15

    This work presents a study of the {sup 1}P{sup 0} excited states of He that can be reached by absorption of a single photon carrying an energy close to the double ionization threshold (DIT) (79 eV). Above the DIT, these states are the double continuum states; below, they are the double excited states. These two types of states are tightly coupled to the single continuum states with or without excitation of the residual ion He{sup +}, owing to their degeneracy in energy. In a one-photon process, these states can only be formed owing to the electronic correlations in the system which must be well described to obtain quantitative good results. Our study is a part of the work which aims at a united description of all these doubly excited, ionized-excited, and double continuum states. We use the Hyperspherical R-Matrix with Semiclassical Outgoing Waves (HRM-SOW) method, initially dedicated to double photoionization studies. We extend it to extract information on the single continuum. This extension allows us to compute cross sections of single photoionization with or without excitation up to n 50 for an excess of 100 meV just above the double ionization threshold. A deep insight into this process is given by a partial waves analysis. The results obtained shed light on the key role of angular and radial correlations. The numerous data we obtain on double and single ionization allow us to establish a continuity relation between these two processes. We show that single ionization with an infinite excitation of the residual ion merges into double photoionization when the excess energy is redistributed between the two electrons. It appears that this relation is valid not only for low but also for high photon energies. Since the HRM-SOW can produce the integrated cross section for double photoionization with high accuracy in the low energy domain, we check the Wannier threshold law. The parameters extracted support strongly this threshold law, and are in good agreement with experimental results. We complete this work with the study of doubly excited autoionizing states.

  2. Electronic structure of ZrO{sub 2}: calculation of optical absorption and of losses; Structure electronique de ZrO{sub 2}: calcul de l'absorption optique et des pertes

    Energy Technology Data Exchange (ETDEWEB)

    Vast, N. [CEA Saclay (DSM/IRAMIS/LSI), 91 - Gif-sur-Yvette (France)

    2007-07-01

    This work is a part of the CEA-CNRS program on the behaviour of materials under irradiation. Its aim is to contribute to scientifically base the predicting methods of the behaviour of ceramic materials under irradiation in using the important development of calculation means. In particular, its role has been 1)to develop the basic knowledge and the interactions physics and 2)to elaborate calculation models at relevant scales. The studied topics are until now, the damage mechanisms, the diffusion under irradiation, the micro-structural evolutions and the incidences on the mechanical properties. (O.M.)

  3. Production and study of mixed Al-Al{sub 2}O{sub 3} thin films for passive electronic circuits; Realisation et etude des couches minces mixtes Al-Al{sub 2}O{sub 3} pour circuits electroniques passifs

    Energy Technology Data Exchange (ETDEWEB)

    Pruniaux, B [Commissariat a l' Energie Atomique, 38 - Grenoble (France). Centre d' Etudes Nucleaires

    1967-07-01

    A new vacuum deposition process, named reactive evaporation, is used to realize passive thin film circuits. Using aluminium, oxidized at various steps in its vapor phase, we obtain: - Al-Al{sub 2}O{sub 3} cermet resistors (R{sub {open_square}} = 10000 {omega}{sub {open_square}}, CTR <{+-} 150 ppm/deg. C) which show oscillations of the resistivity versus the thickness of the layer, in distinction to classical theory. - Al{sub 2}O{sub 3} capacitors (C{sub {open_square}} = 60000 pf/cm{sup 2}, tg {delta} < 0.5 per cent). These thin film components present good electrical behaviour and should find interesting applications in integrated circuits. (author) [French] Une nouvelle technique de depot sous vide, l'evaporation reactive est utilisee pour realiser des circuits passifs en couches minces. En oxydant, en phase vapeur, de l'aluminium a differents degres, on obtient: - des resistances en cermet Al-Al{sub 2}O{sub 3} (R{sub {open_square}} = 10000 {omega}{sub {open_square}}, CTR <{+-} 150 ppm) dont Ia resistivite oscille en fonction de l'epaisseur, contrairement aux previsions de la theorie classique. - Des capacites en Al{sub 2}O{sub 3} (C{sub {open_square}} = 60000 pf/cm{sup 2}, tg {delta} < 0.5 pour cent). Ces elements presentent de bonnes caracteristiques electriques et seraient avantageusement utilises en circuits integres. (auteur)

  4. Electronic structure of Pu-Ce(-Ga) and Pu-Am(-Ga) alloys, stabilized in the {delta} phase; Structure electronique d'alliages Pu-Ce(-Ga) et Pu-Am(-Ga) stabilises en phase {delta}

    Energy Technology Data Exchange (ETDEWEB)

    Dormeval, M

    2001-09-01

    The behaviour of {delta}-plutonium, stable between 319 and 451 deg C, exhibits numerous singularities which are still a mystery for both physicists and metallurgists. This is due to its complex electronic structure, and in particular to the 5f electrons, which are at the edge between localization and delocalization. The stability domain of the {delta} phase can be extended down to room temperature by alloying with so called 'deltagen atoms' such as gallium (Ga), aluminum (A1), cerium (Ce) or americium (Am). The present work deals, one the one hand, with the influence of cerium and americium solutes regarding the localization of the 5f electrons of {delta}-plutonium, in binary Pu-Ce and Pu-Am alloys. On the other hand, the effect of two different deltagen solutes, simultaneously present, on the stability of the {delta} phase has been studied in ternary Pu-Am-Ga and Pu-Ce-Ga alloys. The electronic structure being strongly related to the crystalline organization, characterization methods such as X-Ray diffraction and EXAFS measurements were used together with electrical resistivity and magnetic susceptibility experiments. These showed that the roles of cerium and americium, supposed to be similar at the beginning of this investigation, are actually very different. Moreover, the additive effect of cerium and gallium, and, americium and gallium, has been demonstrated. Studying plutonium alloys, which are radioactive, also means following their evolution in time. The characteristics of the alloys have then been followed which allowed to detect, in Pu-Ce(-Ga) alloys, a destabilization of the {delta} phase and, to observe, in Pu-Am(-Ga) alloys, the influence of self-irradiation defects on the magnetic response. (author)

  5. Data acquisition interface for calculating heat diffusion in certain electronic circuits; Interface d`acquisition des donnees permettant le calcul de la diffusion de la chaleur dans certains circuits electroniques

    Energy Technology Data Exchange (ETDEWEB)

    Spiesser, Ph.

    1996-05-01

    A user interface has been developed for geometrical and thermal data acquisition, in order to allow calculations of heat diffusion in certain types of electronic circuits such as power hybrids and compact electronic modules, using computerized simulations. Data management, structure and organization, the data acquisition interface program, and variables and sources, are described

  6. Studies of suprathermal emission due to cyclotron-electronic heating of the tokamak TCV plasma; Etudes du rayonnement suprathermique emis lors du chauffage cyclotronique electronique du plasma du tokamak TCV

    Energy Technology Data Exchange (ETDEWEB)

    Blanchard, P

    2002-07-01

    Photo sensitization of wide band gap semiconductors is used in a wide range of application like silver halide photography and xerography. The development of a new type of solar cells, based on the sensitization of meso porous metal oxide films by panchromatic dyes, has triggered a lot of fundamental research on electron transfer dynamics. Upon excitation, the sensitizer transfers an electron in the conduction band of the semiconductor. Recombination of the charge separated state is prevented by the fast regeneration of the dye by an electron donor present in solution. Until recently, most of the work in this area has been focused on the competition between the recombination and the regeneration processes, which take place in the nanosecond to millisecond regime. With the development of solid-state femtosecond laser, the measurement of the dynamics of the first electron transfer step occurring in the solar cell has become possible . Electron injection from ruthenium(Il) poly pyridyl complexes into titanium dioxide has been found to occur with a poly exponential rate, with time constants ranging from < 100 fs up to > 10 ps. In spite of the lately acquired capacity to measure the dynamics of these reactions, the physical meaning of this poly exponential kinetics and the factors that can influence this process are still poorly understood. In this work, the development of a new femtosecond pump-probe spectrometer, intended to monitor the ultrafast dynamics of electron injection, is presented. The study of this process requires an excellent temporal resolution and a large wavelength tunability to be able to excite a great variety of dyes and to probe the different products of the reaction. These specifications were met using the latest progress made in optical parametric amplification, which allowed the construction of a versatile experimental set-up. The interfacing by computer of the different devices used during the experiments increase the ease of use of the set-up. Transient absorption spectra, using a white light continuum probe beam, were recorded to characterize the absorption features of the species involved in the electron injection process. The dynamics of the injection were then followed with a better accuracy, using two non collinear optical parametric amplifiers generating the pump and probe beams. Enhancement of the pump and probe pulses interaction geometry, improvement of the detection limit of the experiment, removal of the coherent artifact and characterization, by Kerr gating in glass, of the chirp of the white light continuum were realized to optimize the experimental set-up. Dynamics of injection of eosin adsorbed on metal oxide colloids was revisited. Discrepancies present in the literature were rationalized by an effect of distance between the sensitizer and semiconductor surface, induced by the presence of polyvinyl alcohol. It was also found that on non-injecting particles, eosin dimers present on the surface underwent ultrafast intermolecular electron transfer. This reaction competed with electron injection when the dye was adsorbed on titanium dioxide particles, resulting in a decrease in the yield of electron injection. Electron injection from a ruthenium(ll) terpyridyl complex into a titanium dioxide nanostructured film was monitored and compared with the dynamics of the excited state of the dye in solution. A good agreement with previous studies, undertaken with similar compounds, was observed. The double exponential, required to fit the data, had time constants of 0.8 and 17 ps. An ultrafast component was hidden by the convolution of the pump and probe pulses. Quantum dots have shown to inject efficiently in wide band gap semiconductors. Among these systems, lead sulfide adsorbed on titanium dioxide seems to be a promising scheme for solar energy to electricity conversion applications. The transient absorption of the conduction band electrons in lead sulfide decays on two time scales of 1.0 ps and 30 ps attributed to the deep trapping of the electron and to the electron-hole recombination, respectively. These dynamics are observed independently of the adsorption of the nanoparticle on an injecting or non-injecting surface. The presence of a hole conductor allowed the interception of the hole in the valence band of lead sulfide with 4 ps time scale and enhances the charge separation. This work is a first step towards a better understanding of electron injection from a dye into the conduction band of a semiconductor. The set-up has been shown to allow the monitoring of ultrafast kinetics, which are in agreement with the literature. The application of the femtosecond spectrometer to photosensitized semiconductors particles ensured the measurement of ultrafast charge transfer dynamics. The design of new experiments should allow for a better comprehension of the factors governing the rate of electron injection. (author)

  7. Dosimetry of an accident in mixed field (neutrons, photons) using the spectrometry by electronic paramagnetic resonance(EPR); Dosimetrie d'accident en champ mixte (neutrons, photons) utilisant la spectrometrie par resonance paramagnetique electronique (RPE)

    Energy Technology Data Exchange (ETDEWEB)

    Herve, M.L

    2006-03-15

    In a radiological accident, the assessment of the dose received by the victim is relevant information for the therapeutic strategy. Two complementary dosimetric techniques based on physical means are used in routine practice in the laboratory: EPR spectroscopy performed on materials removed from the victim or gathered from the vicinity of the victim and Monte Carlo calculations. EPR dosimetry, has been used successfully several times in cases of photon or electron overexposures. Accidental exposure may also occur with a neutron component. The aim of this work is to investigate the potentiality of EPR dosimetry for mixed photon and neutron field exposure with different organic materials (ascorbic acid, sorbitol, glucose, galactose, fructose, mannose, lactose and sucrose). The influence of irradiation parameters (dose, dose rate, photon energy) and of environmental parameters (temperature of heating, light exposure) on the EPR signal amplitude was studied. To assess the neutron sensitivity, the materials were exposed to a mixed radiation field of experimental reactors with different neutron to photon ratios. The relative neutron sensitivity was found to range from 10% to 43% according to the materials. Prior knowledge of the ratio between the dose in samples measured by EPR spectrometry and organ or whole body dose obtained by calculations previously performed for these different configurations, makes it possible to give a first estimation of the dose received by the victim in a short delay. The second aim of this work is to provide data relevant for a quick assessment of the dose distribution in case of accidental overexposure based on EPR measurements performed on one or several points of the body. The study consists in determining by calculation the relation between the dose to the organs and whole body and the dose to specific points of the body, like teeth, bones or samples located in the pockets of victim clothes, for different external exposures corresponding to most representative configurations. (author)

  8. Échecs thérapeutiques chez les enfants infectés par le VIH en suivi de routine dans un contexte à ressources limitées au Cameroun

    Science.gov (United States)

    Penda, Calixte Ida; Bebey, Francine Same; Mangamba, Danielle Kedy; Moukoko, Else Carole Eboumbou; Ngwa, Victoria; Makouet, Nicaise; Bissek, Anne-Cécile; Minkemdefo, Blaise Dupont; Tetanye, Ekoe; Ndombo, Paul Koki

    2013-01-01

    Introduction L'objectif de cette étude était de déterminer les facteurs associés aux échecs thérapeutiques chez les enfants infectés par le VIH à l'Hôpital Laquintinie de Douala. Méthodes Une étude transversale rétrospective a été menée sur une période de 5 mois en 2010, recrutant 222 enfants âgés de 1 à 18 ans et sous TARV depuis au moins 24 semaines. Les données sociodémographiques, cliniques, biologiques et de l'observance thérapeutique des patients ont été collectés à partir des dossiers des patients, et analysées avec le logiciel SPSS (version 16). Résultats 39 (17,6%) des enfants étaient en échec thérapeutique (délai moyen de survenue 26,8 mois) et 73,4% d'entre eux sont passés en seconde ligne. Les garçons avaient en moyenne un risque 5 fois plus élevé de faire un échec thérapeutique que les filles (OR=3,9; p=0,035). 94,4% des enfants suivis avaient un faible taux de CD4 à l'initiation (‘ 25%) associé au risque élevé d’échec thérapeutique (OR=5,2; p=0,007). Les enfants issus de famille monoparentale représentaient près de la moitié des cas d’échecs thérapeutiques. Sur 39 cas en échec thérapeutique, 41% des enfants étaient des orphelins. Parmi les enfants sous TARV, 46% prenaient leur trithérapie sous forme de médicaments séparés parmi lesquels 52,1% étaient en échec thérapeutique. Conclusion Les échecs thérapeutiques et le passage en seconde ligne dépendaient du contexte familial des enfants, de leur statut immunologique à l'initiation du traitement, de leur sexe et de la forme galénique du TARV. PMID:24171063

  9. Ressource efficient IT in schools. Options of an energie-efficient and material-efficient use in information technology; Ressourceneffiziente IT in Schulen. Optionen des energie- und materialeffizienten Einsatzes von Informationstechnik (IT)

    Energy Technology Data Exchange (ETDEWEB)

    Clausen, Jens; Fichter, Klaus [Borderstep Insitut, Berlin (Germany)

    2009-12-15

    The number of computers in schools increases continuously. This requires a use of material-efficient and energy-efficient IT technologies. As an alternative to traditional large desktop personal computers (PC), there are three types of computer solutions with a significant improvement: Mini PCs, notebooks and Thin Client and Server Based Computing. Schools need to reflect fundamentally on more material-efficient and more energy-efficient IT solutions and consider the system change to server-based computing as an alternative. Thus, the information and training of IT personnel in schools plays as a central role such as the expansion of the competence of advising and supervising system houses. This is the only way to reduce material costs, energy consumption and administration costs despite an increasing number of computer devices and to exploit existing potentials for resource efficiency.

  10. Conséquences de l'interaction entre préférences pour l'habitat et quantité de ressources trophiques sur les communautés d'insectes coprophages (Coleoptera: Scarabaeoidea)

    Science.gov (United States)

    Kadiri, Nassera; Lobo, Jorge M.; Lumaret, Jean-Pierre

    Between the years 1988 and 1995, five dung beetle communities were studied in combined conditions of habitat and trophic resources. Investigations were conducted on La Viale experimental farm, in the Causse Méjean, southern France. At each site, dung beetle traps of standard design were set up simultaneously. In most situations, the vegetation cover acted like a filter that allowed the penetration of several ubiquitous but fundamentally open-habitat dung beetle species into forest, at the same time drastically limiting their numbers. Open and close sites differed significantly, open and grazed sites showing the highest richness, abundance and biomass in beetles. Both in open and close sites, a significant increase in trophic resources led to an increase of the diversity and evenness. However in open-habitat, when resources were too abundant, few species were favoured and the diversity and evenness decreased. In forest-habitat, a continuous grazing during several years (increase in resources) modified the dung beetle community, with a high increase in the numbers and biomass of beetles but a smaller increase in richness. Numbers in forest habitat readjusted to the level observed in open habitat with equivalent trophic resources. Similarly to what was observed in open pastures, the forest communities were able to adjust their numbers to the level of available trophic resources. Resources were a more active variable than the structure of habitat on the dung beetle communities. Important resources go against the filter effect which allows the penetration under cover of open-habitat species. Changes were slow (several years), and forest communities remained weak. The poverty of forest habitats is discussed: This scarcity in species is probably due to long time human activities in Europe which drastically reduced forest habitats and developped grazing, favouring generalist and heliophilous open-habitat dung beetle species. Actual grassland communities in Europe are richer than their homologous communities in North America. Conversely, in North America where human activities are recent, the true forest dung beetle communities are still diverse and richer than grassland communities.

  11. CO sub 2 induced climate change in Ontario: Interdependencies and resource strategies. Changement climatique cause par le CO sub 2 en Ontario: Interdependances et strategies en matiere de ressources

    Energy Technology Data Exchange (ETDEWEB)

    1988-01-01

    A summary is presented of a workshop held in November 1985 which was convened to extend the results of an earlier study on the effect of CO{sub 2}-induced climate change on specific components of the air-water-land biota systems and resource uses in Ontario. The workshop examined the interdependencies of those impact sectors and possible resource and socio-economic strategies to mitigate the effects of climate change. Impacts on such matters as streamflow, water quality, wetlands, snowfall, solar energy, municipal water use, hydroelectric power, tourism and recreation, food production, forest resources, and residential heating requirements were evaluated. It was found that almost all components of the climate system and resource use were affected by CO{sub 2}-induced warming, but the nature and magnitude of these impacts vary considerably across resource sectors and are intricately interdependent. Direct impacts are driven by changes in temperature, precipitation, or cloud cover and affect climate system components, and interdependencies among these sectors cause indirect impacts which affect resource use. For example, changes in temperaure and precipitation affect streamflow which indirectly impacts water use, commercial shipping, and recreation. Strategies to mitigate these effects include both preventive and adjustment strategies, some of which require significant forward planning. The timing and pattern of CO{sub 2}-induced change are important in determining the most likely and desirable strategies. A 5-point framework was developed to evaluate strategies and identify research priorities. Among resource and socioeconomic adjustment strategies, research into the forestry sector is of primary importance.

  12. Déplier le dispositif. La mobilité du chercheur comme ressource pour l’étude de l’expertise médico-légale1

    OpenAIRE

    Juston, Romain

    2017-01-01

    Cet article propose de voir dans la notion de dispositif un type de problématisation invitant le chercheur à adopter une démarche en mouvement. Il illustre cette proposition à partir de notre recherche sur l’expertise médico-légale. Saisi comme un dispositif, cet objet peut être déplié sur deux plans distincts à partir desquels l’enquête de terrain s’est déroulée : le plan des protocoles qui, des ministères aux services, vise à organiser les activités médico-légales ; celui des rapports d’exp...

  13. Développement durable à l'échelle de la planète et gestion des ressources en eau et en solsSustainable development on a global scale and management of water and soil resources

    Science.gov (United States)

    Petit, Michel

    2003-06-01

    Despite some controversies, an international consensus on what is sustainable development has emerged, the nature of which is first specified. Then the author explains why the implementation of the measures consistent with this consensus comes up against obstacles, particularly political ones, which makes clear why the topic is still under animated debate. Examples will be taken in the domain of the management of water and soils resources. To cite this article: M. Petit, C. R. Geoscience 335 (2003).

  14. Etablissement de scénarios alternatifs de valorisations alimentaires et non alimentaires des ressources céréalières wallonnes à l'horizon 2030

    Directory of Open Access Journals (Sweden)

    Van Stappen, F.

    2014-01-01

    Full Text Available Alternative scenarios for food and non-food uses of Walloon cereals by 2030. Topic. Based on the current uses of cereals grown in Wallonia (Belgium, various scenarios defining possible futures for the Walloon cereal sector have been created. Purpose. These scenarios lay the basis for research aiming at assessing the sustainability of food and non-food uses of cereals. Method. Based on contrasted hypotheses, four scenarios for the uses of Walloon cereals by 2030 have been defined with the support of stakeholders involved in all the steps of the chain. Results. The first scenario, called "Business-as-Usual", extrapolates trends from 15 years before 2010 and up to 2030. In the second scenario, called "Strategic", the current system is optimized from the environmental, economic and social point of view. The third and fourth scenarios break with current trends. The third scenario, called "Localization", considers an increased autonomy and the development of new cereal processing units in Wallonia. The fourth scenario, called "Globalization", focuses on a massive level of cereal export in response to an increasing demand from the global market and deals with high added-value products within Wallonia. Conclusions. Issues such as competition between food uses and non-food uses of cereals and of Walloon dependency on imports are addressed in these scenarios illustrating possible future situations, from food self-sufficiency to dramatic globalization, through the development of new outlets combining the adaptation of cropping practices, consumption, the evolution of habits and the use of new technologies.

  15. Extension spatiale de la salinisation des ressources en eau et modèle conceptuel des sources salées dans la plaine des Triffa (Maroc nord-oriental)

    Science.gov (United States)

    Boughriba, Mimoun; Melloul, Abderrahmane; Zarhloule, Yassine; Ouardi, Abdelillah

    2006-09-01

    The succession of drought years and excessive abstraction in the plain of Triffa caused deterioration in water quality and endangers future exploitation of groundwater resources. A combination of geophysical surveys, including electrical resistivity and hydrochemical data has been used to identify the geographical extension of salinization and identify its origin. Electrical conductivity measurements are used to show the history of salinization in space and time. In this paper, a first conceptual model of the brackish springs has been established. To cite this article: M. Boughriba et al., C. R. Geoscience 338 (2006).

  16. Étude méthodologique de la conservation de ressources génétiques de ray-grass anglais (graminée fourragère) par multiplication en pools de populations naturelles

    OpenAIRE

    Balfourier , François; Charmet , G

    1994-01-01

    À partir d’une collection de 547 populations naturelles de ray-grass anglais, préalablement étudiées pour des caractères d’intérêt agronomique, 42 populations sont choisies à l’aide d’analyses multivariables et en fonction de critères agronomiques et écogéographiques, afin de constituer 9 pools typés et représentatifs de la diversité observée. Cette méthode de constitution de pools est présentée comme une étape de présélection, permettant la conservation de la diversité et la préparation...

  17. Multiple criteria decision aid : a tool for implementing integrated resource management; L`aide a la decision multicritere : un outil de mise en oeuvre de la gestion integree des ressources forestieres

    Energy Technology Data Exchange (ETDEWEB)

    Boivin, R. [Quebec Univ., Dept. des sciences de l`environnement, Montreal, PQ (Canada); Waaub, J.P. [Quebec Univ., Dept. de geographie, Montreal, PQ (Canada)

    1999-05-01

    A proposal of a multicriteria multistakeholder decision making process for use in resource management is presented. The important issues surrounding decision making are described and the general methodology of the process is explained. The ecological mapping contributions as part of a spatial analysis framework for species biodiversity assessment are also reviewed. The process makes use of the PROMETHEE-GAIA multicriteria multistakeholder software package. The proposed process is discussed in the context of wood harvesting operations and biodiversity conservation in a multi-resource environment.

  18. Le déploiement d'une capacité d'Open Marketing dans une organisation marketing : analyse selon une approche par les ressources, les capacités et les compétences marketing

    OpenAIRE

    Moraux, Hélène

    2014-01-01

    Marketing has been given a strong interface and connection role within the literature, creating the assumption of a naturally “open” marketing. However, specifically, the opening of the marketing organization is not so obvious. In a theoretical paper, Day (2011) introduces the Open Marketing concept, defined as a capability to open the marketing organization to partners’ networks so as to gain marketing insights and capabilities in order to enrich the firm’s marketing. The concept is interest...

  19. Les algues, une ressource aux applications multiples : Nutrition, Santé, Cosmétologie, Bioénergie, Environnement [The algae, a resource with multiple applications: Nutrition, Health, Cosmetics, Bioenergy, Environment

    Directory of Open Access Journals (Sweden)

    Gérard TREMBLIN

    2016-06-01

    Full Text Available Marine algae present a potential source of compounds with numerous applications in fields as different as, food processing, health, cosmetics, aquaculture, nutraceuticals, environment and renewable energy. Lipids and pigments are the main products of interest in large seaweeds or macroalgae and in microalgae composing the phytoplankton. Macroalgae have long been the subject of industrial use as gelling source (agar, carrageenan, alginate or food uses (nori, wakame, kombu. Some species are harvested and others are grown. Microalgae, for their part are the focus, for recent years, of many industrial projects such as, pigment production, omega-3 fatty acids production or more generally lipids for a future use as a biofuel resource. They are cultured in photo-bioreactors or open tanks in many regions of the world. Among the microalgae, a diatom rich in omega-3, cultivated industrially in the region of "Pays de la Loire" and commercialized as a human food supplement, has been studied in order to optimize its valorisation. Results, obtained for optimal conditions of development in culture and the advantages of using it as a food supplement for preventing cardiovascular risk factors in rats subjected to a high fat diet, are presented.

  20. Etude ethnobotanique des ressources forestières ligneuses de la forêt marécageuse d'Agonvè et terroirs connexes au Bénin

    Directory of Open Access Journals (Sweden)

    Tenté, AHB.

    2012-01-01

    Full Text Available Ethnobotanical Study of Ligneous Species in Agonvè Swampy Forest and Surrounding Area in Benin. Quantitative ethnobotanical study was conducted with the local community around Agonve forest, which is one of southern Benin swampy forest. This study enables to describe the different use categories of woody plant species for local population and to determine the use value (UV of each species. A total of 28 woody species were identified as useful species for the local population in different use categories such as medicine, food, fire wood and construction. The principal component analysis on the matrix (use forms* species showed that the populations did not log the tree species which they considered as useful for food or medicine. There was no significant difference regarding the overall ethnobotanical use value between the surrounding villages (p= 0.344, F= 1.08 and dF= 2. Among the useful species, Dialium guineense (UVT= 8.98, Spondianthus preussii (UVT= 7.68 and Raphia hookeri (UVT= 7.16 were the most use species by the local population. Finally the study pointed out the importance of the ethnobotanical use value as tool to select the species which conservation must be emphasized in the management plans to meet not only the need of the populations but also to improve the conservation statute of the species.

  1. Optimisation de l'utilisation des ressources communes dans le bassin arachidier du Sénégal : évaluation ex ante de plans et d'alternatives de gestion durable

    Directory of Open Access Journals (Sweden)

    Sanogo, D.

    2014-01-01

    Full Text Available Optimizing the use of common resources in the groundnut basin of Senegal: An ex-ante evaluation of plans and alternatives for sustainable management. The preservation of inter village forestry and pastoral spaces (ESPIVs is an endogenous initiative, introduced by local communities in the groundnut basin of Senegal, to meet the combined effects of climate change and resource degradation. Located outside crop-growing areas, these community reserves are a source of fodder for livestock and for local transhumance, and they provide additional income for rural populations. The preservation of these ESPIVs is supported by management tools such as the Simple Management Plan (PSG and the Development and Management Plan (PAG. In some cases, the economic impact of these plans on poverty reduction at the community level is very noticeable. But in other cases, the expectations of the communities are not being met. This article is an ex-ante evaluation of the projected management plans of two ESPIVs in the groundnut basin of Senegal. The results show that simpler management options involving reduced areas would make only a small contribution to local development, even when consolidated with various incitative measures. Management options involving interventions in the infrastructure of vast areas with a high forest-product potential would have a positive impact on the economic surplus of the members of those communities, hence reinforcing possibilities for local development. However, this approach is controversial and simpler management options therefore need to be re-assessed. These simpler options would involve alternatives for revenue generation, such as taxation for access to common land resources by transhumant livestock and the marketing of non-ligneous forest products. This study shows the limits of PSG compared to PAG and proposes alternatives for improved approaches to managing ESPIVs. Thus, the study provides decision-makers with possible negotiating tracks in a situation requiring the sustainable management of common resources within a context of decentralization.

  2. La pollution des sols des champs d’épandage d’eaux usées, contrainte et/ou ressource pour le développement durable en plaine de Bessancourt-Herblay-Pierrelaye

    Directory of Open Access Journals (Sweden)

    Vincent Mandinaud

    2005-11-01

    Full Text Available Historiquement affectés à l’assainissement des eaux usées brutes et à l’amendement des sols, les champs d’épandage de la ville de Paris, puis du SIAAP, sont au début de l’année 1997 en passe d’être publiquement reconnus pollués par des Eléments Traces Métalliques (ETM . Différentes opérations participent de ce double processus de reconsidération des risques associés à l’épandage et de requalification des entités territoriales concernées. La présentation dynamique des prises et des contraintes développées, en plaine de Bessancourt-Herblay-Pierrelaye singulièrement, permet de montrer comment la pollution des sols peut (réactiver localement une réflexion collective sur un développement territorial durable.

  3. Diagnosis and management of acute coronary syndrome

    Directory of Open Access Journals (Sweden)

    Baker Hamilton

    2013-09-01

    La prévalence des maladies cardiovasculaires connaît une croissance rapide dans les pays en développement, entraînant une incidence croissante du syndrome coronarien aigu (SCA. Les modalités de diagnostic et de traitement de cette maladie continuent d’évoluer, et il convient de tenir compte des ressources locales lors de la réalisation d’un diagnostic et la détermination des options thérapeutiques. Cet article constitue un guide à la prise en charge du SCA fondé sur l’expérience, et fournit des recommandations spécifiques destinées aux médecins hospitaliers travaillant dans les pays à bas et moyen revenu. Le diagnostic du SCA, y compris les SCA sans élévation du ST et avec élévation du ST, se concentre sur la stratification du risque, la vigilance relative aux manifestations subtiles ou atypiques, et la prise en considération d’autres causes des douleurs poitrinaires. Le processus de diagnostic implique l’évaluation des facteurs de risque, la connaissance des antécédents médicaux défavorables et les conclusions de l’examen physique (des variantes étant susceptibles d’exister dans les différentes populations, ainsi que l’utilisation de tests de diagnostic appropriés. Il est recommandé d’utiliser de l’aspirine à titre de traitement initial, parallèlement à un antiagrégant plaquettaire supplémentaire. Le prasugrel est préféré au clopidogrel si le patient présente un SCA avec élévation du ST et qu’une intervention coronaire percutanée (ICP est prévue. La bivalidurine devrait être le premier choix pour éviter la coagulation dans les SCA avec élévation du ST, suivie de l’enoxaparine (qui ne nécessite pas de perfusion, puis d’héparine non fractionnée. Pour les patients présentant un SCA sans élévation du ST et en cas de risque de saignement accru, le fondaparinux devrait être envisagé à la place de l’énoxaparine. Les patients souffrant de dyspnée, présentant des signes d

  4. : tous les projets | Page 197 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Les initiatives de réduction de la consommation de sel qui visent l'ensemble de la population et qui ciblent la teneur en sodium des aliments et sensibilisent les consommateurs sont susceptibles de réduire la consommation de sel dans toutes les couches de la population et d'améliorer la santé cardiovasculaire.

  5. Prevalence de l'hypertension arterielle et des principaux facteurs de ...

    African Journals Online (AJOL)

    Prevalence de l'hypertension arterielle et des principaux facteurs de risque cardiovasculaire en milieu professionnel a Lome. ... La definition de lfhypertension arterielle retenue etait celle de lfOMS et JNC VI (TA . 140/90 mmHg. Un examen clinique et un bilan minimal de lfOMS etaient realises pour chaque travailleur.

  6. Research

    African Journals Online (AJOL)

    abp

    24 juin 2015 ... Page number not for citation purposes. 1. Epaisseur de l'intima-média carotidienne et facteurs de risque cardio-vasculaires. Nicolas Fanantenana Herinirina1, Lova Hasina Ny Ony Narindra Rajaonarison2,&, Andry Roussel Herijoelison3, Ahmad Ahmad2. 1Service Imagerie Médicale, Centre Hospitalier ...

  7. Geluid en gezondheid : achtergrondstudie

    NARCIS (Netherlands)

    Passchier-Vermeer, W.

    1993-01-01

    Dit rapport geeft een overzicht van de huidige kennis op het terrein van de invloed van geluid op de gezondheid van de mens. Er wordt niet alleen nagegaan wat de invloed is van blootstelling aan geluid op lichamelijke functies, zoals het cardiovasculaire systeem en het gehoororgaan, maar komen ook

  8. Journal de la Recherche Scientifique de l'Université de Lomé

    African Journals Online (AJOL)

    Journal de la Recherche Scientifique de l'Universite de Lome. ... B.A.K. Dossa, V.J. Mama, S Karimou, A.C. Mamam-Djibril, T Houetchegnon, I Toko .... des facteurs de risque cardiovasculaire et de cancer dans l'aire sanitaire de Zowla au Togo ...

  9. Browse Title Index

    African Journals Online (AJOL)

    Journal de la Recherche Scientifique de l'Universite de Lome. ... Épidémiologie managériale des facteurs de risque cardiovasculaire et de cancer dans l'aire ... NC Kelome, M Agassounon Djikpo Tchibozo, L Ayi Fanou, J Vihotogbe, D Mama.

  10. Steroids and steroid analogues for Hormone Replacement Therapy; Metabolism in target tissues

    NARCIS (Netherlands)

    Blom, M.J.

    2001-01-01

    Bij vrouwen na de menopause is er een sterke daling van de oestradiol concentraties in het bloed. Hoewel oestradiol oorspronkelijk alleen beschouwd werd als een geslachtshormoon, heeft dit hormoon ook invloed op een groot aantal andere organen, waaronder het skelet, het cardiovasculaire systeem en

  11. Effective lifestyle interventions to improve type II diabetes self-management for those with schizophrenia or schizoaffective disorder: : a systematic review

    NARCIS (Netherlands)

    prof Berno van Meijel

    2012-01-01

    Patiënten met schizofrenie of een schizo-affectieve stoornis hebben een verhoogde kans op diverse somatische ziektes, zoals cardiovasculaire aandoeningen, virale ziektes, diabetes, respiratoire aandoeningen en seksuele stoornissen. Deze ziektes dragen ertoe bij dat de levensverwachting van deze

  12. Malformations vasculaires au cours du syndrome de Williams ...

    African Journals Online (AJOL)

    Le syndrome de Williams-Beuren est une maladie génétique rare, il associe classiquement une dysmorphie faciale assez spécifique, des malformations cardiovasculaires et un profil neuropsychologique particulier. Nous rapportons les observations de trois enfants atteints du syndrome de Williams-Beuren en insistant ...

  13. Electrochemical reduction of graphited materials in LiClO{sub 4}-EC and LiClO{sub 4}-PC media: characterization of interface products by transmission electron microscopy; Reduction electrochimique de materiaux graphites en milieux LiCIO{sub 4}-EC et LiCIO{sub 4}-PC: caracterisation des produits d`interface par microscopie electronique a transmission

    Energy Technology Data Exchange (ETDEWEB)

    Billaud, D.; Naji, A.; Ghanbaja, J. [Universite Henri Poincare Nancy, 54 - Vandoeuvre-les-Nancy (France); Willmann, P. [Centre National d`Etudes Spatiales (CNES), 31 - Toulouse (France)

    1996-12-31

    The electrochemical intercalation of non-solvated lithium in different graphited materials has been performed in LiClO{sub 4}-ethylene carbonate (EC) medium. The irreversible capacity observed during the first output is mainly due to the formation of a passivation layer made of electrolyte reduction products. These products have been characterized for different electrode reduction potentials using transmission electron microscopy (image, diffraction) and electron energy loss spectroscopy (EELS). EC reduction on the electrode surface in presence of LiClO{sub 4} leads to the formation of Li{sub 2}CO{sub 3} for potentials close to 0.8 V vs Li{sup +}/Li. For lower potentials, the electrolyte reduction reaction goes on with the formation of different lithium alkyl-carbonates. In LiClO{sub 4}-propylene carbonate (PC) medium, the interface phenomena are different. The reduction of a graphite electrode is characterized by the exfoliation phenomenon which hinders lithium intercalation. On the contrary, the formation of the passivation layer by graphite reduction in LiClO{sub 4}-EC medium allows the cycling of the electrode in the LiClO{sub 4}-PC electrolyte. In this case, the irreversible capacity observed during the first output depends on the experimental conditions of formation of the passivation layer. Abstract only. (J.S.)

  14. Study of secondary electron emission from thin carbon targets with swift charged particles: heavy ions, hydrogen ions; Etude experimentale de l`emission electronique secondaire de cibles minces de carbone sous l`impact de projectiles rapides: ions lourds, ions hydrogene (atomiques, moleculaires ou sous forme d`agregats)

    Energy Technology Data Exchange (ETDEWEB)

    Billebaud, A

    1995-07-12

    The main subject of this work is the study of electron emission from the two surfaces of thin solid targets bombarded with swift charged particles. The slowing down of swift ions in matter is mainly due to inelastic interaction with target electrons (ionization, excitation): the energy transfer to target electrons is responsible for the secondary electron emission process. The phenomenological and theoretical descriptions of this phenomena are the subject of the first chapter. We focused on secondary electron emission induced by different kind of projectiles on thin carbon foils. In chapter two we describe hydrogen cluster induced electron emission measurement between 40 and 120 keV/proton. These projectiles, composed of several atoms, allowed us to study and highlight collective effects of the electron emission process. We extended our study of electron emission to molecular (H{sub 2}{sup +}, H{sub 3}{sup +}) and composite (H{sup -}, H{sup 0}) projectiles at higher energies (<= 2 MeV): we have designed an experimental set-up devoted to electron emission statistics measurements which allowed us to study, among others things, the role of projectile electrons in secondary electron emission. This experiment is described in the third chapter. Finally, the fourth chapter describes new measurements of electron emission induced by energetic (13 MeV/u) and highly charged argon ion provided by the medium energy beam line (SME) of GANIL (Caen), which have been analyzed in the framework of a semi-empirical model of secondary electron emission. This set of experiments brings new results on composite projectile interaction with matter, and on the consequences of high energy deposition in solids. (author).

  15. Study of an electronic and algorithmic circuit intended for the management of autonomous systems of photovoltaic energy production; Etude d'un circuit electronique et algorithmique destine a la gestion de systemes autonomes de production d'energie photovoltaique

    Energy Technology Data Exchange (ETDEWEB)

    Izzo, P.

    2002-12-15

    This PhD thesis is connected to the EDF-ADEME project concerned with the decentralized rural electrification in Developing countries. More particularly we are concerned with renewable energies. Solar energy appears tempting because of the abundance of sunlight in some countries. Photovoltaic development currently undergoes a fast expansion, especially in the case of individual installations. The improvements of the functionalities of these installations as well as the reduction in the costs constitute a priority. The analysis of the systems in function shows that the element most ill used is the battery and that the management of it is not always adapted to preserve the system during the most critical situations. The work presented in this thesis concentrates on a phenomenon in lead-acid batteries, and which is critical when the battery is used for managing photovoltaic energy systems: recrystallization of sulphates. Tests in real conditions, confirmed in laboratory, showed the precocity of the phenomena of recrystallization. It appeared that this phenomenon is combined with the stratification of the electrolyte. It is known indeed that the stratification supports the recrystallization, which leads to the sulphate formation known as 'irreversible'. We noted that the recrystallization and the operations of de-stratification could be in contradiction. The work done at the level of management functionalities consisted in: - initially, to correct the effects of recrystallization, and the parameters of the de-stratification functions, -secondly to develop new functions in order to recover the active matter trapped in the form of 'irreversible sulphates'. These functionalities are carried out for two families of managers: elementary kits for minimal systems and multi-batteries managers for more consequent installations. (author)

  16. Study of the appearance of oscillating electron neutrinos issued from muon neutrino beam in the K2K experiment; Etude de l'apparition de neutrinos electroniques oscillant a partir de neutrinos muoniques du faisceau de l'experience K2K

    Energy Technology Data Exchange (ETDEWEB)

    Argyriades, J

    2006-05-15

    The work presented in this thesis has been done in the K2K experiment. His principle consists in the use of a beam of muon neutrinos, which flux has been measured at short and long distances. Those data enable us to study the effects of neutrino oscillation, particularly by measuring {nu}{sub {mu}} disappearance. Although this is not an appearance experiment, electronic neutrinos oscillation has been searched. In spite of no signal of appearance, this study enables to constrain oscillation parameters ({delta}m{sub 23}{sup 2}, sin{sup 2}2{theta}{sub 13}). With one event for 1,07 expected event from background, the exclusion area edges are close to the best actual limits, provided by Chooz experiment. By setting {delta}m{sub 23}{sup 2}.= 2,8.10{sup -3} eV{sup 2}, a limit at 90% confident level is reached: sin{sup 2}2{theta}{sub 13} < 0,2. (author)

  17. Development of a heterodyne micro-wave reflectometer with ultra-fast sweeping. The study of the plasma turbulence influence on the measurements of electron density profile; Developppement d`un reflectometre micro-onde heterodyne a balayage ultra rapide. Etude de l`influence de la turbulence du plasma sur la mesure des profils de densite electronique

    Energy Technology Data Exchange (ETDEWEB)

    Moreau, Philippe [Aix-Marseille-1 Univ., 13 - Marseille (France)

    1997-10-17

    The density profile of the fusion plasmas can be investigated by the reflectometry diagnostics. The measurement principle is based on the radar techniques which calculate the phase shift of a millimeter wave propagating into the plasma and reflected at a cut-off layer. However, this propagation is perturbed by the plasma turbulence. These phenomena affect the phase delay measurement by not well understood a process. In this work we have tried to find the mechanisms and origin of the turbulence which is responsible for the phase disturbance. We point out the role of collisionality and plasma radiation in controlling the instability and also, demonstrate that the phase delay of the probing wave is very sensitive to the plasma MHD phenomena and is less affected by the micro-turbulence. The second part of this work is the development and the use of a new heterodyne reflectometer. The principal characteristics are given. Its heterodyne detection allows the separation of phase and amplitude information from the detected signal and then to study their contribution to the mechanism of signal perturbation. The use of this reflectometer allows us to point out the following points: - a high dynamic availability, required by the large amplitude drops, often greater than 30 db; - fast sweep operation requirement to `freeze` the plasma turbulence; - multiple reflection effects which modulate the amplitude and phase of the probing wave if they are not suppressed by filtering the detected signal; - very good localisation of the measurement (of the order of millimeter). The heterodyne reflectometer developed during this work offers several advantages of different distinct reflectometry techniques (fast sweep, absolute and differential phase measurements, heterodyne detection). It could be developed to work over higher frequency range so as to measure density profile over larger radial extension with very high performances. (author) 93 refs., 101 figs., 8 tabs. 3 ills.

  18. A study of an optimal technological solution for the electronics of particle position sensitive gas detectors (multiwire proportional chambers); Etude d`une solution technologique optimale pour l`electronique de localisation des particules avec des detecteurs a gaz (chambre proportionelle multifils)

    Energy Technology Data Exchange (ETDEWEB)

    Zojceski, Z. [Institut de Physique Nucleaire, CNRS - IN2P3 Universite Paris Sud, 91406 Orsay Cedex (France)

    1997-12-31

    This work aims at optimizing the electronics for position sensitive gas detectors. The first part is a review of proportional chamber operation principles and presents the different possibilities for the architecture of the electronics. The second part involves electronic signal processing for best signal-to-noise ratio. We present a time-variant filter based on a second order base line restorer.It allows a simple pole-zero and tail cancellation at high counting rates. Also, various interpolating algorithms for cathode strip chambers have been studied. The last part reports the development of a complete electronic system, from the preamplifiers up to the readout and control interface, for the cathode strip chambers in the focal plane of the BBS Spectrometer at KVI, Holland. The system is based on application specific D-size VXI modules. In all modules, the 16-bit ADCs and FIFO memory are followed by a Digital Signal Processor, which performs data filtering and cathode induced charge interpolation. Very good analog noise performance is obtained in a multi-processor environment. (author). 127 refs.

  19. Electron microscopy and auger spectroscopy study of the wetting of the grain boundaries in the systems Mo-Pb, Mo-Sn, Mo-Ni and Ni-Pb; Etude par microscopie electronique et spectroscopie auger du mouillage des joints de grains dans les systemes Mo-Pb, Mo-Sn, Mo-Ni et Ni-Pb

    Energy Technology Data Exchange (ETDEWEB)

    Charai, A. [Faculte des Sciences et Techniques de Saint Jerome, Lab. TECSEN, UMR 6122 du CNRS, 13 - Marseille (France); Kutcherinenko, I.; Priester, L. [Paris-11 Univ., ISMA, 91 - Orsay (France); Penisson, J.M. [CEA Grenoble, Dept. de Recherche Fondamentale sur la Matiere Condensee, DRFMC-SP2M, 38 (France); Pontikis, V. [Centre National de la Recherche Scientifique (CNRS), Centre d' Etudes de Chimie Metallurgique, 94 - Vitry-sur-Seine (France); Wolski, K. [Ecole NationaleSuperieure des Mines de Saint Etienne, Centre SMS/MPI, URA 1884 du CNRS, 42 - Saint Etienne (France); Vystavel, T. [Academy of Sciences of Czech Republic, Institute of Physics, Praha (Czech Republic)

    2002-09-01

    Understanding the mechanism of the intergranular penetration of a liquid phase into a metallic solid is an important problem. The structural and chemical characterization of nano-metric films at grain boundaries is now possible by using high resolution electron microscopy associated with X-ray micro-analysis, electron energy loss spectroscopy and Auger spectroscopy. In order to study this problem, two different classes of model materials were selected according to their crystallographic structure: a bcc metal (molybdenum) and an fcc one (nickel). The wetting element was either lead or tin or nickel. In a first approach, the metallic matrix was polycrystalline. The conditions in which the liquid phase penetrates into the grain boundaries were studied by using special preparation and observation techniques. In particular, the use of a Focused Ion Beam microscope (FIB) allowed the preparation of thin foils located very precisely inside the matrix as well as multi-scale observations. These specimens were further observed in electron microscopy with a very high resolution. (authors)

  20. Study of a continuous plasma generated by electron bombardment and its mixing with a laser induced plasma. Influence of collisions on resonance cone phenomenon; Contribution a l`etude d`un plasma cree de facon continue par bombardement electronique et de son melange avec un photo-plasma pulse. Influence des collisions sur les cones de resonance

    Energy Technology Data Exchange (ETDEWEB)

    Besuelle, E.

    1997-02-25

    This thesis deals with three different fields of plasma physics. In the first part, we studied free expansion of an ionised uranium vapour generated in an electron beam evaporator. The electron temperature and the electron density of the expanding plasma have been measured by a Langmuir probe. The experimental results have been compared with the ones obtained by numerical simulation using a fluid code. The calculated points are in the error bars. We observe that there are two electron populations with different temperatures, which undergo a mixing during the plasma expansion. The neutral density influence on the electron temperature by collisional relaxation is also studied. The second part deals with a plasma diagnostic which can replace Langmuir probe in the case of a cold magnetized plasma: the resonance cone phenomenon. After recalling the wave propagation theory in a cold plasma, we introduce a new calculation of the potential radiated by an antenna in a collisional magnetized plasma. The domain where the resonance cone exists in considerably reduced because of collisions. More of that, the cone angle is reduced by this phenomenon too. The experiments performed show that we must take into account a wave turbulence phenomenon to explain the High collision frequency that we observe. The third part is about the study of the expansion of a plasma into another one. We solve this problem with fluid codes and Particle-In-Cell (PIC) code. THe electron families have a counter stream motion locally. Then, we study the electrostatic extraction of two plasmas-one pulsed, one continuous-in which we observe electron unfurling. (author).

  1. Study and realization of the electronic power supply of a variable reluctance motor for electric-powered vehicle - motor experimenting; Etude et realisation de l'alimentation electronique d'un moteur a reluctance variable pour vehicule electrique - experimentation du moteur

    Energy Technology Data Exchange (ETDEWEB)

    Mouchoux, J.C.

    1994-10-15

    This work deals with the development of a propulsion system comprising a 27 kW double salience variable reluctance motor supplied by a tri-phase inverter with asymmetrical half-bridges capable to switch 400 A under 120 V. Control is ensured by a numerical control system based on a digital signal processor. The control strategy comprises two control modes: a torque trapeze one in order to minimize the undulations at low speed, and a full voltage wave one for high speeds (up to 10000 rpm) in order to use the full motor efficiency. This study presents: the operation principle of the motor and the control laws chosen, the converter design and testing, the elaboration of a single-phase numerical model of the motor, the analysis of the power supply simulation results for each control mode chosen, and the measurements of the control-converter-motor efficiencies. (J.S.)

  2. Study of isobutyric acid reactivity by electron spin resonance and infrared spectroscopy of the sodium salt and of 1-vanado-11-molybdophosphoric acid; Etude de la reactivite de l`acide isobutyrique par spectroscopie infrarouge et resonance paramagnetique electronique du sel de sodium et de l`acide de l`ion 1-vanado-11-molybdophosphorique

    Energy Technology Data Exchange (ETDEWEB)

    Rabia, C.; Bettahar, M.M. [Universite des sciences et de technologies, Houari-Boumediene, Algiers (Algeria); Fournier, M. [Universite des Sciences et technologies de Lille, 59 - Villeneuve d`Ascq (France)

    1997-11-01

    The alkaline salt 1-vanado-11-molybdo-phosphore acid as been investigated in isobutyric absorption-desorption-re-oxidation cycles by IR and ESR spectroscopies in comparison to the bulk acid compound. The stability of the active phase in catalysis seems to be related to the formation of a cubic phase depending strongly on the presence of water vapor in the gas stream. This phase can be generated from an alkali precursor subject to a moderate thermal treatment leading to a dispersion of di-oxovanadium cation into the alkali-12-molybdophosphate lattice. (authors) 14 refs.

  3. Contribution to the electrothermal simulation in power electronics. Development of a simulation methodology applied to switching circuits under variable operating conditions; Contribution a la simulation electrothermique en electronique de puissance. Developpement d`une methode de simulation pour circuits de commutation soumis a des commandes variables

    Energy Technology Data Exchange (ETDEWEB)

    Vales, P.

    1997-03-19

    In modern hybrid or monolithic integrated power circuits, electrothermal effects can no longer be ignored. A methodology is proposed in order to simulate electrothermal effects in power circuits, with a significant reduction of the computation time while taking into account electrical and thermal time constants which are usually widely different. A supervising program, written in Fortran, uses system call sequences and manages an interactive dialog between a fast thermal simulator and a general electrical simulator. This explicit coupling process between two specific simulators requires a multi-task operating system. The developed software allows for the prediction of the electrothermal power dissipation drift in the active areas of components, and the prediction of thermally-induced coupling effects between adjacent components. An application to the study of hard switching circuits working under variable operating conditions is presented

  4. Electric properties of organic and mineral electronic components, design and modelling of a photovoltaic chain for a better exploitation of the solar energy; Proprietes electriques des composants electroniques mineraux et organiques, conception et modelisation d'une chaine photovoltaique pour une meilleure exploitation de l'energie solaire

    Energy Technology Data Exchange (ETDEWEB)

    Aziz, A

    2006-11-15

    The research carried out in this thesis relates to the mineral, organic electronic components and the photovoltaic systems. Concerning the mineral semiconductors, we modelled the conduction properties of the structures metal/oxide/semiconductor (MOS) strongly integrated in absence and in the presence of charges. We proposed a methodology allowing characterizing the ageing of structures MOS under injection of the Fowler Nordheim (FN) current type. Then, we studied the Schottky diodes in polymers of type metal/polymer/metal. We concluded that: The mechanism of the charges transfer, through the interface metal/polymer, is allotted to the thermo-ionic effect and could be affected by the lowering of the potential barrier to the interface metal/polymer. In the area of photovoltaic energy, we conceived and modelled a photovoltaic system of average power (100 W). We showed that the adaptation of the generator to the load allows a better exploitation of solar energy. This is carried out by the means of the converters controlled by an of type MPPT control provided with a detection circuit of dysfunction and restarting of the system. (author)

  5. A study of an optimal technological solution for the electronics of particle position sensitive gas detectors (multiwire proportional chambers); Etude d`une solution technologique optimale pour l`electronique de localisation des particules avec des detecteurs a gaz (chambre proportionelle multifils)

    Energy Technology Data Exchange (ETDEWEB)

    Zojceski, Z [Institut de Physique Nucleaire, CNRS - IN2P3 Universite Paris Sud, 91406 Orsay Cedex (France)

    1998-12-31

    This work aims at optimizing the electronics for position sensitive gas detectors. The first part is a review of proportional chamber operation principles and presents the different possibilities for the architecture of the electronics. The second part involves electronic signal processing for best signal-to-noise ratio. We present a time-variant filter based on a second order base line restorer.It allows a simple pole-zero and tail cancellation at high counting rates. Also, various interpolating algorithms for cathode strip chambers have been studied. The last part reports the development of a complete electronic system, from the preamplifiers up to the readout and control interface, for the cathode strip chambers in the focal plane of the BBS Spectrometer at KVI, Holland. The system is based on application specific D-size VXI modules. In all modules, the 16-bit ADCs and FIFO memory are followed by a Digital Signal Processor, which performs data filtering and cathode induced charge interpolation. Very good analog noise performance is obtained in a multi-processor environment. (author). 127 refs.

  6. Electronic structure of the actinides and their dioxides. Application to the defect formation energy and krypton solubility in uranium dioxide; Etude de la structure electronique des actinides et de leurs dioxydes. Application aux defauts ponctuels et aux gaz de fission dans le dioxyde d`uranium

    Energy Technology Data Exchange (ETDEWEB)

    Petit, T. [CEA Centre d`Etudes Nucleaires de Grenoble, 38 (France)]|[CEA Centre d`Etudes de Grenoble, 38 (France). Dept. de Thermohydraulique et de Physique

    1996-09-28

    Uranium dioxide is the standard nuclear fuel used in French h power plants. During irradiation, fission products such as krypton and xenon are created inside fuel pellets. So, gas release could become, at very high burnup, a limiting factor in the reactor exploitation. To study this subject, we have realised calculations using the Density Functional Theory (DFT) into the Local Density Approximation (LDA) and the Atomic Sphere Approximation (ASA). First, we have validated our approach by calculating cohesive properties of thorium, protactinium and uranium metals. The good agreement between our results and experimental values implies that 5f electrons are itinerant. Calculated lattice parameter, cohesive energy and bulk modulus for uranium and thorium dioxides are in very good agreement with experiment. We show that binding between uranium and oxygen atoms is not completely ionic but partially covalent. The question of the electrical conductivity still remains an open problem. We have been able to calculate punctual defect formation energies in uranium dioxide. Accordingly to experimental observations, we find that it is easier to create a defect in the oxygen sublattice than in the uranium sublattice. Finally, we have been able to predict a probable site of krypton atoms in nuclear fuel: the Schottky trio. Experiences of Extended X-ray Absorption Fine structure Spectroscopy (EXAFS) and X-ray Photoelectron Spectroscopy (XPS) on uranium dioxide doped by ionic implantation will help us in the comprehension of the studied phenomena and the interpretation of our calculations. (author). 256 refs.

  7. Electric properties of organic and mineral electronic components, design and modelling of a photovoltaic chain for a better exploitation of the solar energy; Proprietes electriques des composants electroniques mineraux et organiques, conception et modelisation d'une chaine photovoltaique pour une meilleure exploitation de l'energie solaire

    Energy Technology Data Exchange (ETDEWEB)

    Aziz, A

    2006-11-15

    The research carried out in this thesis relates to the mineral, organic electronic components and the photovoltaic systems. Concerning the mineral semiconductors, we modelled the conduction properties of the structures metal/oxide/semiconductor (MOS) strongly integrated in absence and in the presence of charges. We proposed a methodology allowing characterizing the ageing of structures MOS under injection of the Fowler Nordheim (FN) current type. Then, we studied the Schottky diodes in polymers of type metal/polymer/metal. We concluded that: The mechanism of the charges transfer, through the interface metal/polymer, is allotted to the thermo-ionic effect and could be affected by the lowering of the potential barrier to the interface metal/polymer. In the area of photovoltaic energy, we conceived and modelled a photovoltaic system of average power (100 W). We showed that the adaptation of the generator to the load allows a better exploitation of solar energy. This is carried out by the means of the converters controlled by an of type MPPT control provided with a detection circuit of dysfunction and restarting of the system. (author)

  8. Two strongly correlated electron systems: the Kondo mode in the strong coupling limit and a 2-D model of electrons close to an electronic topological transition; Deux systemes d'electrons fortement correles: le modele de reseau Kondo dans la limite du couplage fort et un modele bidimensionnel d'electrons au voisinage d'une transition topologique electronique

    Energy Technology Data Exchange (ETDEWEB)

    Bouis, F

    1999-10-14

    Two strongly correlated electron systems are considered in this work, Kondo insulators and high Tc cuprates. Experiments and theory suggest on one hand that the Kondo screening occurs on a rather short length scale and on the other hand that the Kondo coupling is renormalized to infinity in the low energy limit. The strong coupling limit is then the logical approach although the real coupling is moderate. A systematic development is performed around this limit in the first part. The band structure of these materials is reproduced within this scheme. Magnetic fluctuations are also studied. The antiferromagnetic transition is examined in the case where fermionic excitations are shifted to high energy. In the second part, the Popov and Fedotov representation of spins is used to formulate the Kondo and the antiferromagnetic Heisenberg model in terms of a non-polynomial action of boson fields. In the third part the properties of high Tc cuprates are explained by a change of topology of the Fermi surface. This phenomenon would happen near the point of optimal doping and zero temperature. It results in the appearance of a density wave phase in the under-doped regime. The possibility that this phase has a non-conventional symmetry is considered. The phase diagram that described the interaction and coexistence of density wave and superconductivity is established in the mean-field approximation. The similarities with the experimental observations are numerous in particular those concerning the pseudo-gap and the behavior of the resistivity near optimal doping. (author)

  9. Study, development and validation of a dead-timeless electronic architecture concept for highly sensitive PET (Positron Emission Tomograph); Etude, developpement et validation d'un concept d'architecture electronique sans temps mort pour TEP de haute sensibilite

    Energy Technology Data Exchange (ETDEWEB)

    Vert, P.E

    2007-03-15

    Positron emission tomographs (PET) are fitted with highly capable reading electronics, which owns qualities and drawbacks. Highly accused at first as an explanation of the poor sensitivity of these imagers, the present study points out that the dead-times shared along the chains contribute to only 16 % in the data losses at a typical activity of 10 {mu}Ci/ml. The gross acquisition rates could thus be raised by 20 % through a suppression of these saturations. Looking in details at the philosophy of the acquisition procedure, a property appears to circumscribe the sensitivity even more: the timing resolution. The latter conditions, to the first order, the rejection capabilities of random events, part of the scattered ones and hence noise which is finally rated to the true coincidences the signal is made up of. Minimizing the resolving time goes through the suppression of the unneeded actors along with the adoption of a well adapted time-stamping method (optimal filtering). In doing so, the intrinsic channel resolution appears to be possibly lowered by a factor 7, reducing to 350 ps. The bottom value of the coincidence window may be narrowed as a consequence, leading to an increase of the NECR (noise equivalent count rate) by 50 per cent. At this stage, a time of flight (TOF) algorithms can be implemented. As an opportunist, it promises a reduction of the noise variance by 430 %, a gain that echoes on the NECR figure. Finally merging all these ideas allows to expect an improvement close to an order of magnitude on the NECR, with the hope of routine exams shortened by the same amount. In this context, it appeared logical to imagine a new electronics acquisition synoptic dedicated to fully pixelized PET. The number of channels blows up by the way when compared to the existing, this statement being partially balanced by the decision to fully integrate the electronics. The measures of the energy and time are planned to be performed with a single channel, with a continuous and dead-timeless reading of the events. The development of the microelectronics circuits is under way, the three first blocks being described in this dissertation. (author)

  10. Design and realization of a space-borne reflectron time of flight mass spectrometer: electronics and measuring head; Conception et realisation d'un spectrometre de masse a temps de vol spatialisable de type 'reflectron' electronique et tete de mesure

    Energy Technology Data Exchange (ETDEWEB)

    Devoto, P

    2006-03-15

    The purpose of this thesis is the design of the electronics of a time of flight mass spectrometer, the making and the vacuum tests of a prototype which can be put onboard a satellite. A particular effort was necessary to decrease to the maximum the mass and electric consumption of the spectrometer, which led to the development of new circuits. The work completed during this thesis initially concerns the electronics of the measuring equipment which was conceived in a concern for modularity. A complete 'reflectron' type mass spectrometer was then designed, simulated and developed. The built prototype, which uses the developed electronics, was exposed to ion flows of different masses and energies in the CESR vacuum chambers. Its measured performances validate the implemented principles and show that an identical mass spectrometer can be put onboard a satellite with profit, for planetary or solar missions. (author)

  11. Scanning electron microscopy and X-ray photoelectron studies of high temperature oxidation mechanism of a Fe-Cr-Al alloy; Etude par microscopie electronique a balayage et spectroscopie de photoelectrons des mecanismes d'oxydation a haute temperature d'un alliage Fe-Cr-Al

    Energy Technology Data Exchange (ETDEWEB)

    Delaunay, F.; Berthier, C.; Lameille, J.M. [CEA Saclay, Dept. d' Entreposage et de Stockage des Dechets (DCC/DPE/SPCP), 91 - Gif-sur-Yvette (France)

    2000-07-01

    The lifetime of high temperature materials is strongly dependent on their resistance to high temperature oxidation. Hence the technical applications of these materials require the formation of a protective, slow growing oxide scale. The efficiency of Cr{sub 2}O{sub 3}- forming alloys above 1100 deg C is limited because Cr{sub 2}O{sub 3} reacts with oxygen to form volatile CrO{sub 3}. It is known that doping alloys with small additions (< 0.1 wt %) can improve mechanical properties and/or alloy oxidation resistance. Fe{sub 20}Cr{sub 5}Al based alloys form protective scale of alumina with slow growth rates at temperatures above 1000 deg C. The alloy composition is given in Table 1. Various techniques have been used to determine the scale morphology, structure and composition of oxide scale, including Scanning Electron Microscopy coupled with Energy Dispersive X-ray Spectrometry, grazing incidence X-ray diffraction, and XPS. During heat treatment at 1150 C, ranging from 5 minutes to 24 hours, a parabolic regime is observed, leading to a protective layer against oxidation. The oxide scale structure mainly consists of thermodynamically stable {alpha}-Al{sub 2}O{sub 3}. After 1 hour, (Mg{sub 1-X}Fe{sub X})Al{sub 2}O{sub 4} appears and increases with treatment time. After 5 minutes at 1150 deg C, X ray maps indicating the location of the elements in the oxide scale were prepared with SEM-EDS. Figure 2 shows that the oxide scale mainly consists of alumina. The secondary electron image shows little islands consisting of yttrium and zirconium on the oxide scale. For longer oxidation time, I hour, XPS results reveal chemical species like Al{sub 2}O{sub 3}),Ti(IV) (TiO{sub 2}), Cr(III) that yttrium and zirconium are not detected. After 24 hours, scale thickness is about 2 {mu}m. Small islands of yttrium and zirconium (and to a lesser degree titanium) are still present. In Figure 4, magnesium and titanium are located on the alumina scale. X-ray maps on cross-sections in Figure 5 show continuous, uniform and adherent scale, in good agreement with Mennicke and al, who also observed that yttrium in Fe{sub 20}Cr{sub 5}Al improves the adherence and uniformity of the protective alumina scale. However, these small islands, when located at the surface, offer oxygen a diffusion path towards the underlying alloy. Figure 5 confirms that titanium and magnesium, present in low concentrations in the alloy, can diffuse across the alumina scale to be oxidized at the surface. In conclusion, oxide scale initially mainly consists of thermodynamically stable {alpha}-Al{sub 2}O{sub 3}, and after longer exposure, titanium and magnesium diffuse towards the surface to form TiO{sub 2} and MgAl{sub 2}O{sub 4}. The addition of yttrium improves the adhesion and uniformity of alumina scale. Little islands of yttrium, zirconium and titanium are present in the alloy, probably due to low solubility, and they may play a role in improving scale adherence by acting as anchoring points. (authors)

  12. Development of an integrated circuit VLSI used for time measurement and selective read out in the front end electronics of the DIRC for the Babar experience at SLAC; Developpement d'un circuit integre VLSI assurant mesure de temps et lecture selective dans l'electronique frontale du compteur DIRC de l'experience babar a slac

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, B

    1999-07-01

    This thesis deals with the design the development and the tests of an integrated circuit VLSI, supplying selective read and time measure for 16 channels. This circuit has been developed for a experiment of particles physics, BABAR, that will take place at SLAC (Stanford Linear Accelerator Center). A first part describes the physical stakes of the experiment, the electronic architecture and the place of the developed circuit in the research program. The second part presents the technical drawings of the circuit, the prototypes leading to the final design and the validity tests. (A.L.B.)

  13. Semi-conducting plastics for disposable electronic devices - What are the organic semi-conductors arriving on the market?; Des plastiques semi-conducteurs pour l'electronique jetable. Qui sont les semi-conducteurs organiques qui arrivent sur le marche?

    Energy Technology Data Exchange (ETDEWEB)

    Nueesch, F. A. [EMPA, Duebendorf (Switzerland)

    2010-07-01

    This is a popularization article that describes basic properties of semi-conductors and reports on the status of research and development of organic semi-conductors. In a first part, fundamentals of semi-conductors are recalled. Comparisons are made between inorganic and organic (i.e. based on carbon polymers) compounds. Indications are given on how semi-conducting polymers are obtained. Potential applications are listed: flexible organic solar cells, light emitting diodes, flexible organic displays, intelligent cards for ticketing, etc. Research on organic semi-conductors is of great interest for industry, worldwide, and several companies are widely investing in this area.

  14. Making of an electronic interferometer to study emissive properties of field-effect microtips. Diffraction and interferences of slow electrons; Construction d`un interferometre electronique pour l`etude des proprietes emissives de micropointes a effet de champ. Diffraction et interferences d`electrons lents

    Energy Technology Data Exchange (ETDEWEB)

    Py, C

    1993-10-01

    The substitution of hot filaments by field-effect microtips has several advantages in many electronic applications. LETI has already proved the interest of this principle for flat panel displays; many people believe it could also provide novel microwave sources. Moreover, the properties of the emission enable to seek new electron optics applications that were not possible with hot filaments. An interferometry experiment was designed, developed and characterized in order to evaluate the potential of the microtips fabricated in the LETI for such applications. This experiment is composed of a Mollenstedt biprism, of electrostatic lenses and an imaging system composed of deflection plates, a small aperture diaphragm (1 {mu}m) and a channel electron multiplier. Quantum wave effects have been observed, which confirms the good coherence properties of the source. Moreover, this experimental setup enables to better understand the physical phenomenon of the emission of the tips fabricated in the LETI, and to propose some technological improvements for the applications we seek. It is also designed for electron holography applications, and should allow the study of new compact electron optics apparatus taking account of the wave properties of the electrons emitted by microtips. (author). 68 figs. 2 annexes. 41 refs.

  15. Abstracts and electronic proceedings of the Canadian Dam Association's 2009 annual conference : protecting people, property and the environment; Resumes et actes electroniques du congres annuel 2009 de l'Association canadienne des barrages : proteger les personnes, les biens et l'environnement

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2009-07-01

    The Canadian Dam Association (CDA) is the Canadian leader in advancing knowledge and practices related to dams. This annual conference provided a professional development opportunity on a broad range of dam-related topics. The technical sessions addressed issues such as adaptation to climate change; the application of safety design for discharge facilities; risks associated with rockfill dams; underlying problems of design floods and dam safety; guidelines for public safety around dams and psychology of safety; the dam safety review process; and run-of-river hydro dams. During the related sessions, Canadian members of the International Committee on Large Dams (ICOLD) commented on international practice and developments. The workshops focused on incident investigations; reliability-centered maintenance; flow discharge gate reliability; piping damage to till core dams; and mining dams. The sessions of the conference were entitled: design floods and dam safety; dam breach flood modelling; dam safety management; public safety; mining dams; flood handling and modelling; case studies; ice loads on structures; seepage control; dam safety reviews and remediation; remote sensing for dams; protecting the environment; seismic hazard and response modelling; and the performance of dams in 2008 earthquake in Sichuan, China. The conference featured 61 presentations, of which 59 have been catalogued separately for inclusion in this database. refs., tabs., figs.

  16. Electrochemical reduction of graphited materials in LiClO{sub 4}-EC and LiClO{sub 4}-PC media: characterization of interface products by transmission electron microscopy; Reduction electrochimique de materiaux graphites en milieux LiCIO{sub 4}-EC et LiCIO{sub 4}-PC: caracterisation des produits d`interface par microscopie electronique a transmission

    Energy Technology Data Exchange (ETDEWEB)

    Billaud, D; Naji, A; Ghanbaja, J [Universite Henri Poincare Nancy, 54 - Vandoeuvre-les-Nancy (France); Willmann, P [Centre National d` Etudes Spatiales (CNES), 31 - Toulouse (France)

    1997-12-31

    The electrochemical intercalation of non-solvated lithium in different graphited materials has been performed in LiClO{sub 4}-ethylene carbonate (EC) medium. The irreversible capacity observed during the first output is mainly due to the formation of a passivation layer made of electrolyte reduction products. These products have been characterized for different electrode reduction potentials using transmission electron microscopy (image, diffraction) and electron energy loss spectroscopy (EELS). EC reduction on the electrode surface in presence of LiClO{sub 4} leads to the formation of Li{sub 2}CO{sub 3} for potentials close to 0.8 V vs Li{sup +}/Li. For lower potentials, the electrolyte reduction reaction goes on with the formation of different lithium alkyl-carbonates. In LiClO{sub 4}-propylene carbonate (PC) medium, the interface phenomena are different. The reduction of a graphite electrode is characterized by the exfoliation phenomenon which hinders lithium intercalation. On the contrary, the formation of the passivation layer by graphite reduction in LiClO{sub 4}-EC medium allows the cycling of the electrode in the LiClO{sub 4}-PC electrolyte. In this case, the irreversible capacity observed during the first output depends on the experimental conditions of formation of the passivation layer. Abstract only. (J.S.)

  17. Contribution to the experimental study of wave particle interactions in a plasma having a two-population electronic distribution function; Contribution a l'etude experimentale de l'interaction ondes-particules dans un plasma presentant une fonction de distribution electronique a deux populations

    Energy Technology Data Exchange (ETDEWEB)

    Frank, R [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1969-07-01

    The aim of this work is the experimental study of the interaction between electrostatic waves and electrons in a plasma characterized by a so called 'bump in tail' distribution function. To study experimentally the mechanism of this interaction it is necessary to measure precisely the electron distribution and its evolution in space or in time. This was performed with an electrostatic separation probe which was designed especially. We measured also the evolution in space and time of the noise spectrum. We studied this mechanism in two different regimes of our discharge: - In the first case the distribution function is very close to that describing the interaction of a semi-infinite plasma with a cold beam injected at its edge. We showed that the instability resulting from this interaction is convective and that the growth of the waves results in a very important modification of the distribution function. The ionization due to the electric field related to the waves is also important. This modification is similar to that described by the quasi linear theory. The mechanism described by this theory remains then qualitatively valid in a strongly non linear case. - In the second case the conditions necessary for the quasi linear theory to be valid are satisfactorily fulfilled. It is then possible to measure, simultaneously, and precisely, the evolution of the distribution function and of the noise spectrum. From these measurements one can deduce the mechanism of the energy exchange between waves and particles and show that it is in good agreement with that described by the quasi linear theory. (author) [French] On presente ici l'etude experimentale detaillee du mecanisme de l'echange d'energie entre les oscillations e la frequence plasma des electrons et des electrons energetiques dans un plasma presentant une fonction de distribution du type a 'double bosse'. Pour realiser cette etude on a mis au point, une 'sonde a separation electrostatique' qui permet de mesurer avec precision la fonction de distribution en energie des electrons et son evolution dans l'espace ou dans le temps. On a pu ainsi, dans un plasma d'hydrogene cree dans une decharge a cathode chaude, etudier le mecanisme de l'interaction entre les ondes et les particules dans deux cas: - dans le premier cas, les conditions necessaires pour l'application de la theorie quasi lineaire sont sensiblement verifiees. On a pu dans ce cas suivre avec precision le developpement de l'instabilite et la deformation de la fonction de distribution qui en resulte. On a montre que dans ce cas le mecanisme decrit par la theorie quasi lineaire etait qualitativement et quantitativement verifie; - dans le second cas, l'interaction entre les ondes et les electrons est beaucoup plus forte que celle qui est decrite par la theorie quasi lineaire et se traduit en particulier par une ionisation assez importante du gaz neutre. On a pu montrer cependant que dans ce cas encore le mecanisme decrit par la theorie quasi lineaire reste qualitativement valable. (auteur)

  18. Study of irradiation effects in the silicon carbide cubic polytype by photoluminescence and electron spin resonance spectroscopies; Etude des effets d'irradiation dans le polytype cubique du carbure de silicium par les techniques spectroscopiques de photoluminescence et de resonance paramagnetique electronique

    Energy Technology Data Exchange (ETDEWEB)

    Lefevre, J

    2008-01-15

    This experimental work has consisted in the study of point defects induced by an electronic irradiation in the cubic crystallographic structure of silicon carbide with low temperature photoluminescence and electron spin resonance spectroscopies. The first one of these measurement tools has allowed to estimate the displacement threshold energy in the silicon sub-lattice and then to analyze the thermal stability of the irradiation defects in the low temperature range: (10-300 K) and then in the high temperature range: (300-1400 K). Besides, on the base of a recent theoretical model, this thesis has confirmed the proposition of the isolated silicon antisite for the D1 center whose running beyond the nominal running temperature of fission nuclear reactors (generation IV), for which SiC is in part intended, seems to be particularly problematic. Measurements carried out by ESR under lighting have at last allowed to detect a new defect in its metastable spin state S=1, possibly associated to a silicon interstitial configuration. (O.M.)

  19. A phenomenon of direct conversion of ionizing energy resulting from the formation of negative droplets by electron capture during condensation of a vapour even without electronic affinity; Sur un phenomene de conversion directe d'energie ionisante resultant de la formation de gouttelettes negatives par capture d'electrons, lors de la condensation d'une vapeur, meme sans affinite electronique

    Energy Technology Data Exchange (ETDEWEB)

    Kraux, P [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1969-06-01

    An electromotive force is produced between a cold and a hot electrode immersed in an ionized vapour. It is shown that the dissymmetry thus created consists in the formation of heavy, negative charge carriers following the condensation of the vapour in the volume close to the cold electrode. The electromotive forces produced are explained on the basis of a decrease in the floating potential of the cold electrode. (author) [French] Une force electromotrice apparaissant entre une electrode chaude et une electrode froide plongees dans une vapeur ionisee, on etablit que la disymetrie ainsi causee consiste en la formation de porteurs de charge negatifs lourds consecutive a la condensation de la vapeur en volume pres de l'electrode froide. On justifie les forces electromotrices observees par la diminution du potentiel flottant de l'electrode froide. (auteur)

  20. Contribution to the study of the sintering of ex-carbonyl iron in the {alpha} and {gamma} phases using the micro-fractographic technique; Contribution a l'etude du frittage du fer ex-carbonyle en phases {alpha} et {gamma} par examen des surfaces de rupture au microscope electronique

    Energy Technology Data Exchange (ETDEWEB)

    Oxley Gaborit de Montjou, M.Th. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1966-07-01

    The micro-fractographic study of the sintering of ex-carbonyl iron has shown or confirmed a number of phenomena of which the principal are as followed: Sintering in the a phase: -) existence of two stages of sintering differentiated by the type of rupture (inter or trans-crystalline); -) marked influence of the content of oxygen in the atmosphere and in the initial compressed sample on the speed of sintering; -) formation of striations on the grain-boundary surfaces and on the inner surface of pores caused by the presence of oxygen. Sintering in the {gamma} phase: -) a pronounced decrease in the speed of sintering: the grains in the initial powder remain in the granular state within the final {alpha} crystal in the iron sintered in the lower {gamma} range even after several hours of sintering; -) this granular structure can be eliminated by intermediate compression thus enabling the sintering process to proceed. A considerable decrease in the speed of sintering if the A{sub 3} point is passed one or more times in the {alpha} range sintering. A high speed sintering if the treatment in the {gamma} range is carried out at or above 1300 C. The results of this study agree with micrographic investigation as well as with dilatometric measurements and known auto-diffusion coefficients. (author) [French] L'etude microfractographique du frittage du fer ex-carbonyle a permis de mettre en evidence ou verifier plusieurs phenomenes dont les principaux sont les suivants: Pour le frittoge en phase {alpha}: -) existence de deux stades de frittage differencies par le type de rupture (inter et transcristalline); -) importance de la teneur en oxygene dans l'atmosphere et dans le comprime initial sur la vitesse de frittage; -) formation de stries dues a la presence d'oxygene sur les plans de joints et a l'interieur des pores. Pour le frittage en phase {gamma}: -) un ralentissement tres prononce de la cinetique du frittage: les granules de la poudre initiale demeurent a l'etat de granules a l'interieur des grains {alpha} finaux dans le fer directement fritte dans le bas du domaine {gamma}, meme apres plusieurs heures de frittage; -) une compression intermediaire permet une reprise du frittage suffisante pour depasser le stade de la structure a granules; -) un net ralentissement du frittage si le point A{sub 3} est franchi une ou plusieurs fois au cours du frittage en {alpha}; -) une cinetique du frittage elevee si le traitement en {gamma} est effectue a 1300 C ou au-dessus de 1300 C. Les resultats de cette etude sont en accord avec les observations micrographiques ainsi qu'avec les mesures dilatometriques et les valeurs connues des coefficients d'autodiffusion.

  1. Theoretical and experimental study of the double ionization by electron impact involving the Auger effect: processes and exchanges interferences; Etude theorique et experimentale de la double ionisation par impact electronique incluant l'effet auger: interferences d'echanges et de processus

    Energy Technology Data Exchange (ETDEWEB)

    Catoire, F

    2006-09-15

    In this work, double ionisation mechanisms of argon by electron impact in which the Auger effect is included have been studied as a function of the incident electron energy. Five and six fold differential cross sections in angle and in energy have been measured and analysed in a coplanar geometry. The efficiency of the apparatus has been improved by the use of a new toroidal analyser. For the first time, the six fold differential cross section in which the Auger electron and the ejected electron with identical kinetic energies (205 eV) are involved, was measured at an incident energy of 956 eV in the case of argon. In the theoretical models developed during this work, the triple continuum is represented by a manifold of coulomb waves describing the interaction of all electrons with the residual ion. Exchange effects between electrons were also included in the models. Comparison between experimental and theoretical results allows to study the relative contribution of the Auger process and the direct double ionisation on the angular dependence five fold differential cross section. In particular, the Auger process contribution seems to become increasingly important as the incident energy is increased.

  2. Importance and Limitations of Scintigraphy of the Pancreas: Results of 200 Examinations involving Electronic Subtraction of the Image of the Liver; Interet et Limites de la Scintigraphie Pancreatique: Resultats de 200 Examens Pratiques avec Soustraction Electronique de l'Image du Foie

    Energy Technology Data Exchange (ETDEWEB)

    Blanquet, P.; Beck, C.; Pigneux, J.; Hecquet, M. F. [Hopital Saint-Andre, Unite de Recherches INSERM, Bordeaux (France)

    1969-05-15

    In the course of routine hospital practice, the authors carried out 200 scintigraphic scans of the pancreas with suppression of the image of the liver. The examinations were made with an Anger camera, used in conjunction with the integrating memory of a 4096-channel pulse analyser. With this arrangement it was possible to subtract the data provided by heavy colloids of {sup 198}Au taken up by the liver from data relating to {sup 75}Se-labelled selenomethionine incorporated by the liver or the pancreas. The technique used is simple and requires immobilization of the patient for about one hour. Its purpose is to give an image of the pancreas free from any superimposed image of the liver and also to provide information on the rate at which the labelled compound is stored in the gland. The dose absorbed by the pancreas is minimal, owing to the short length of time that the radioisotope remains within the gland. The dose received by the whole body is not negligible and therefore the number of examinations made on subjects with a clinically normal pancreas was limited to five. Although its principle is open to criticism, the subtraction technique gave completely satisfactory results in practice. Suppression of the liver image was not always complete but in all cases the image of the pancreas was sufficiently isolated to allow interpretation of it as a whole. It should, however, be noted that the zone of projection common to the two organs is often somewhat inhomogenous after subtraction has been effected. In subjects free from pancreatic disorders, the scintigram was in all cases normal. In the cases of confirmed chronic pancreatitis the picture is unequivocal. The tumours can manifest themselves in a variety of scintigraphic images, but the definition of the images may be regarded as satisfactory since in one case the scintigram showed up a tumorous formation estimated to measure 2 cm at that time. (author) [French] Les auteurs ont pratique, en routine hospitaliere, 200 scintigraphies pancreatiques avec suppression de l'image du foie. Les examens ont ete realises a l'aide d'une camera d'Anger couplee a un analyseur a memoire integratrice de 4096 canaux. Cet ensemble a permis la soustraction des donnees fournies par les gros colloiedes d'or-198 fixes au niveau du foie de celles fournies par la selenomethionine marquee au selenium-75 fixee danslesglandeshepatiquesetpancreatiques. La technique est simple dans son execution; elle immobilise le sujet examine pendant une heure environ. Elle a pour objet la realisation d'une image pancreatique debarrassee de toute superposition hepatique et l'etude de la vitesse de stockage du produit marque dans la glande. La dose absorbee par le pancreas est minime etant donne le court sejour du radioelement dans la glande. Celle recue par l'organisme entier n'est pas negligeable; ainsi, le nombre des examens effectues chez des sujets a pancreas cliniquement normal a ete limite a cinq. Critiquable dans son principe, la technique de soustraction a donne entiere satisfaction dans la pratique. L'effacement de l'image du foie n'est pas toujours complete mais dans tous les cas l'image pancreatique est suffisamment isolee pour pouvoir etre interpretee dans son ensemble. Il faut pourtant remarquer que la zone de projection commune aux deux organes est souvent, apres soustraction, un peu inhomogene. Chez les sujets indemnes d'affection pancreatique, le scintigramme a toujours ete normal. Dans les cas de pancreatite chronique confirmee, le tableau est univoque. Les tumeurs peuvent avoir des traductions scintigraphiques variees, mais la definition des images parait satisfaisante puisqu'un des scintigrammes a mis en evidence une formation tumorale evaluee a 2 cm lors de l'intervention. (author)

  3. Etude des melanges co-continus d'acide polylactique et d'amidon thermoplastique (PLA/TPS)

    Science.gov (United States)

    Chavez Garcia, Maria Graciela

    Les melanges co-continus sont des melanges polymeriques ou chaque composant se trouve dans une phase continue. Pour cette raison, les caracteristiques de chacun des composants se combinent et il en resulte un materiau avec une morphologie et des proprietes particulieres. L'acide polylactique (PLA) et l'amidon thermoplastique (TPS) sont des biopolymeres qui proviennent de ressources renouvelables et qui sont biodegradables. Dans ce projet, differents melanges de PLA et TPS a une haute concentration de TPS ont ete prepares dans une extrudeuse bi-vis afin de generer des structures co-continues. Grace a la technique de lixiviation selective, le TPS est enleve pour creer une structure poreuse de PLA qui a pu etre analysee au moyen de la microtomographie R-X et de la microscopie electronique a balayage MEB. L'analyse des images 2D et 3D confirme la presence de la structure co-continue dans les melanges dont la concentration en TPS. se situe entre 66% et 80%. L'effet de deux plastifiants, le glycerol seul et le melange de glycerol et de sorbitol, dans la formulation de TPS est etudie dans ce travail. De plus, nous avons evalue l'effet du PLA greffe a l'anhydride maleique (PLAg) en tant que compatibilisant. On a trouve que la phase de TPS obtenue avec le glycerol est plus grande. L'effet de recuit sur la taille de phases est aussi analyse. Grace aux memes techniques d'analyse, on a etudie l'effet du procede de moulage par injection sur la morphologie. On a constate que les pieces injectees presentent une microstructure heterogene et differente entre la surface et le centre de la piece. Pres de la surface, une peau plus riche en PLA est presente et les phases de TPS y sont allongees sous forme de lamelles. Plus au centre de la piece, une morphologie plus cellulaire est observee pour chaque phase continue. L'effet des formulations sur les proprietes mecaniques a aussi ete etudie. Les pieces injectees dont la concentration de TPS est plus grande presentent une moindre

  4. Pipelines på universiteter og i ledelse

    DEFF Research Database (Denmark)

    Møllgaard, Peter

    2016-01-01

    På et universitet er mennesker den allervigtigste ressource. Det siger man sikkert i mange virksomheder, men forskere og samfundet investerer enorme mængder tid og ressourcer for at de samme forskere kan blive eksperter inden for deres respektive områder. Den fortsatte udvikling af forskere - og ...

  5. Er HRM andet end en sten i skoen?

    DEFF Research Database (Denmark)

    Holt Larsen, Henrik

    2015-01-01

    Ledelse. Arbejdet med virksomheders menneskelige ressourcer kræver, at ledelsen tror på det. Ellers kan det gå ud over HRM-indsatsen.......Ledelse. Arbejdet med virksomheders menneskelige ressourcer kræver, at ledelsen tror på det. Ellers kan det gå ud over HRM-indsatsen....

  6. Strategic Outsourcing in the German Engine Building Industry

    DEFF Research Database (Denmark)

    Gretzinger, Susanne

    2008-01-01

    Outsourcing is an organizational measure that changesthe ressource dependencies of a Company. In this paper, a framework is developed from the perspective of the ressource dependence approach to explain strategic outsourcing in the German engine building industry. On the basis of the NIFA panel...

  7. Gestionnaire, Relations de travail et relations avec les employés (h/f ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Assurer l'établissement de rapports organisationnels fiables sur le rendement de la gestion des ressources humaines par rapport au Plan de mise en oeuvre des ressources humaines, au Rapport annuel du CRDI, aux tableaux de bord organisationnels et autres obligations de production de rapports en coordonnant la ...

  8. Sud du Sahara | Page 74 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Langue English. Read more about Les SIG-P au service d'une gestion durable des ressources naturelles et de la sécurité alimentaire en Afrique. Langue French. Read more about Adaptation aux changements climatiques en ce qui concerne l'agriculture et les ressources en eau dans la Corne de l'Afrique. Langue French.

  9. Innovation, apprentissage et cadres institutionnels dans des ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Trois secteurs de transformation des ressources naturelles - ceux des pâtes et ... devrait déboucher sur des recommandations concrètes pour l'élaboration de ... bibliothèque de ressources aideront à améliorer les systèmes d'information et ...

  10. De l’activité virtuelle à l’activité réelle : ressources et empêchements à la créativité de cadres formés au management d’équipe avec un serious gaming

    OpenAIRE

    Martin , Lydia

    2015-01-01

    This thesis speaks about the creativity and conformity in serious gaming and the link with real work situations of executives. To explore this link, we conducted a training program using an army helicopter flight simulator that had been redesigned to train executives in teamwork. The study was conducted over two years in 16 game sessions with 44 volunteer participants from the same company. The research analyzed the gap between prescribed and real work. In English, contrary to French, there a...

  11. A new geothermal source for spa and space heating in Lavey-les-Bains; Operation geothermique de Lavey-les Bains (VD). CESLA - Chaleur des Eaux Souterraines de Lavey S.A. Realisation du forage geothermique profond P600 et exploitation de la ressource energetique par pompage dans les puits P600 et P201 (juin 1997 - decembre 2002)

    Energy Technology Data Exchange (ETDEWEB)

    Bianchetti, G.

    2002-07-01

    This report presents the construction and the operating performance of a newly drilled borehole in Lavey-les-Bains in Switzerland, which is used to extract high-temperature geothermal water. Associated with an older geothermal source, this well delivering water at the temperature of 68 {sup o}C meets 95% of the heat demand of the Lavey medical and thermal centre, without any heat pump. The heat is used for space heating, ventilation and domestic hot water preparation as well as for the pools. The flow rate from this 517 meter deep well is typically 1,100 liters per minute. The report also describes in details the drilling process as well as the various measurements performed during this period of time. Plenty of figures and schematics are given concerning the technical characteristics of the well and its exploitation procedure. The author suggests the introduction of heat recovery, as water is rejected at a temperature of at least 30 {sup o}C.

  12. Small to average output energy supply that do not burden the environment or resources with one-family houses to multiple-family dwelling; Alimentation d'habitations uni- et multi-familiales avec une energie qui ne greve ni l'environnement ni les ressources

    Energy Technology Data Exchange (ETDEWEB)

    Bloomfield, D.P. [Analytic Power Corporation (United States); Hartan, J.; Robner, I.; Wieschebrink, G. [VNG, Verbundnetz Gas AG (Germany)

    2000-07-01

    The rapid development of the general technical, economic and political conditions leads to a new point of view towards the domestic application of natural gas. The economical aspect of an in-house gas point may still be improved for instance by decentralization of energy conversion facilities by use of state-of-the-art technologies. Within the framework of various research projects the VNG Verbundnetz Gas Aktiengesellschaft Leipzig has proved its technological feasibility by its ERDGASHAUS (i.e. 'Natural Gas House') concept. This concept integrates all domestic energy conversion processes. (authors)

  13. Les nanovésicules extracellulaires sécrétées par les CSMs et les nanovésicules de synthèse issues d’agro-ressources : de leur caractérisation à leur utilisation en ingénierie tissulaire

    OpenAIRE

    Dostert , Gabriel

    2017-01-01

    Nanoscale extracellular vesicles (nEVs) derived from mesenchymal stem cells (MSCs) and synthetic nanovesicles are at the centre of many research studies for the development of new therapeutic strategies in regenerative medicine. A standardized method was used to isolate nEVs from conditioned media of CSMs and to characterize them. We focused on their size with a range of 30 to 150 nm and the presence of some of their membrane markers (CD9, CD63 and CD81). During this work, two isolation metho...

  14. Focus 2012. Awakening into a new age - Elements of a sustainable energy supply. Ressource efficiency - key competency of sustainable societies, Sustainable chemistry - fundamental building blocks of a green economy. Annual report; Schwerpunkte 2012. Aufbruch ins neue Zeitalter - Elemente einer nachhaltigen Energieversorgung, Ressourceneffizienz - Schluesselkompetenz zukunftsfaehiger Gesellschaften, Nachhaltige Chemie - elementarer Baustein einer Green Economy. Jahrespublikation

    Energy Technology Data Exchange (ETDEWEB)

    Mavromati, Fotini; Ittershagen, Martin [comps.

    2012-05-30

    The Federal Environmental Agency (Dessau-Rosslau, Federal Republic of Germany) sees excellent opportunities to move the economic regeneration forward by means of environmental protection. Under this aspect, the annual report ''Focus 2012'' under consideration presents the following contributions: (1) Green Economy as a new model for economic development; (2) Elements of a sustainable energy supply; (3) Resource efficiency as a key competence for sustainable societies; (4) Green Chemistry as a fundamental building block of Green Economy.

  15. No 2902. Proposal of law dealing with the durable management of forest resources in the consideration of the fight against greenhouse effect; No 2902 proposition de loi portant sur la prise en compte de la lutte contre l'effet de serre par la gestion durable des ressources forestieres

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2006-02-15

    This proposal of law aims at implementing viable financial incentive systems for the improvement of forests management resources in France. The easily available but still unemployed wood fuel resource represents today about 10 million tons. (J.S.)

  16. Prognosis, prospecting and development of gas fields in the far north of Siberia - as a single methodological approach to an optimal development of the territorial resources; Prevision, prospection et developpement des champs de gaz naturel du grand nord Siberien - approche methodologique unique pour un developpement optimal des ressources du territoire

    Energy Technology Data Exchange (ETDEWEB)

    Remizov, V.V.; Dmitrievsky, A.N.; Ermilov, O.M.; Neelov, Y.V.; Chugunov, L.S.; Gurari, F.G.; Goldin, S.V.; Karagodin, Y.N. [OJSC Gaprom, Russian Academy of Sciences (Russian Federation)

    2000-07-01

    This presentation realizes a systems approach to the study of the oil and gas complex of the Far North of Siberia as a single sophisticated system starting from prognosis and prospecting of fields to their development at different stages of operation. This paper shows for the first time the whole complex of studies, including the methodology of systems studies of the structure, evolution and genesis of oil and gas reservoirs, the model of geologic structure and the evaluation of oil and gas resources, the technique of prospecting and surveys of oil and gas fields, techniques and methods of an effective system of prospecting and development, particularly at the stage of achieving maximum and the onset of production decrease. (authors)

  17. La marque «Parc Naturel Régional» :un dispositif original pour valoriser des stratégies de développement durable fondées sur les ressources agricoles et agroalimentaires des territoires insulaires ultramarins

    Directory of Open Access Journals (Sweden)

    Armelle Caron

    2009-06-01

    Full Text Available Les Parcs Naturels Régionaux (PNR français créés en 1967 constituent de véritables laboratoires pour la mise en œuvre d’un développement durable avant la lettre. Ils ont expérimenté diverses initiatives visant à valoriser la conservation des patrimoines naturel et culturel de leur territoire, notamment une politique de marquage de produits et de services territorialement ancrés. Dans cet article, nous nous interrogeons sur la pertinence de ces instruments de développement local pour les territoires insulaires à partir de l'exemple de la politique de marquage mise en œuvre par le PNR de la Martinique. Nous intéressant plus particulièrement aux impacts des démarches de marquage en termes de dynamique d’action collective, nous centrons notre analyse sur la dimension « sociale » de la durabilité.French Regional Nature Parks (RNP, created in 1967, can be considered as precursory sustainable development laboratories. Different initiatives dedicated to promote local development and draw benefits from the improved status of sustainably managed areas have been implemented in the RNP and among them a labelling policy through the development of RNP collective trademarks. In this article, we wonder about the consistency of this RNP labelling policy for the French overseas department of Martinique. According to our analytical references (local governance and collective action, we focus on the social dimension of sustainable development.

  18. Soil - a scarce resource. The Ministry of Food, Agriculture and Fisheries' report on the interaction between food, feed and bioenergy. Danish potential in an international perspective; Jorden - en knap ressource. Foedevareministeriets rapport om samspillet mellem foedevarer, foder og bioenergi. Dansk potentiale i et internationalt perspektiv

    Energy Technology Data Exchange (ETDEWEB)

    2008-01-15

    The competition concerning utilization of agricultural soil has multiple causes. Prospects of climate change, growing energy consumption, environmental related controls on agricultural production, increase in population and wealth in e.g. China and India are some of the challenges that will influence future acreage use in agriculture. The present debate on biofuels based on agricultural crops puts focus on utilization of agricultural soil. Knowledge synthesis on biomass has documented that production and use of biomass is a complex area which is highly influenced by global conditions. The complexity is underlined by the numerous significant aspects within economy, trade, technology, environment and ethics which influence biomass. Therefore the political interest and regulation of biomass are subject to many considerations, especially as regards international regulation. In May 2007 the Danish Ministry of Food, Agriculture and Fisheries appointed a project group in order to clarify the relationship between the various uses of biomass, including the risk of not being able to maintain the present balance between growing food and crops for other purposes. The group has taken stock of the overall situation. The group's results are presented in this report. (BA)

  19. Discussion of risks of platinum resources based on a function orientated criticality assessment. Shown by cytostatic drugs and automotive catalytic converters; Diskussion der Risiken der Ressource Platin auf Basis eines um funktionale Faktoren erweiterten Kritikalitaetsassessments. Dargestellt am Beispiel platinhaltiger Zytostatika und Autoabgaskatalysatoren

    Energy Technology Data Exchange (ETDEWEB)

    Thorenz, Andrea; Reller, Armin [University of Augsburg, Chair of Resource Strategy, Environment Science Center, Augsburg (Germany)

    2011-12-15

    The purpose of the study is the enhancement of criticality assessments for resources in order to address function specific factors like dissipation, recycling, bio-activity and toxicity. The developed methodology is applied to platinum-containing cytostatic drugs and automotive catalytic converters. Methods: The study is methodically based on an analysis of resource specific factors like exploration rates, reserves-to-production ratio and regional distribution of exploration areas as well as on the investigation of product/functional depending factors like recycling rates, dissipation rates, bio-diversity and toxicity. Taking into account that economic and ecological risks may occur at any stage of the supply, consumption and dissipation processes, the whole life cycles of the two analyzed products (cytostatic drugs and automotive catalytic converters) are considered. As an approach to reduce potential economic and ecological risks the study is especially focused on recycling strategies. In order to get a better understanding of platinum as an essential resource for the development of our society the history and the cultural impact of the term ''resource'' are introduced. The availability of platinum is crucial for several products of our modern society. Areas of application are e.g. jewellery, automotive catalytic converters, investments (coins, bars), computers, mobile devices, fertilizers and cytostatic drugs. Economic risks are caused by limited sources and dynamic demand of new application areas like fuel cells and drugs. Platinum-containing drugs are used for the treatment of several kinds of cancer such as testicular, breast, colon and prostate. Currently the pharmaceutical industry requires 6,9 tons per year (3 percent of the total demand of platinum). Due to the improvement of medical standards and the ageing society, especially in developing countries, the demand of platinum-containing drugs will rise significantly. The dissipation of toxic soluble salts and the lack of advanced waste-water treatment and recycling systems is a problem of the usage of platinum.containing drugs. Compared with cytostatic drugs (14.6 kg/a for Germany) the dissipation of platinum particles of mobile catalytic converters is much higher (5-20 tons/a only in North America, Europe and Japan; 184,2 kg/a in Germany). On the other hand the emission of platinum nano-particles of automotive catalytic converters seems less critical. Furthermore advanced recycling technologies are already available for them. The evaluation of resources has to consider resource specific and functional depending factors. In order to reduce economic and ecological risks of the dissipation of platinum salts in cytostatic drugs three principle options can be identified: the development of ecologically compatible and cost-effective substitutes, efficient recycling systems and future-oriented sanitary-systems as well as waste-water treatment facilities, which are able to separate platinum salts. Concerning the dissipation of platinum particles of mobile converters relevant research questions are the identification of adequate substitutes as well as the extension of recycling capacities. The study demonstrates a research gap concerning substitutes for automotive catalytic converters as well as for platinum-containing cytostatic drugs. The development and implementation of recycling concepts, technologies and capacities to reuse platinum as a secondary resource is an essential issue. As a consequence the economic and ecological risks can be reduced by increasing the resource efficiency. Special research has to be done concerning the development of future-oriented sanitary-systems and waste-water treatment facilities in order to separate platinum in waste water. Furthermore, if the future demand of new products like fuel cells is considered, a resource conflict concerning the potential functional applications will be evident. In order to address these challenges the criticality assessment has to be enhanced by ethic and social factors.

  20. La concurrence entre les diverses ressources énergétiques fossiles sur le marché européen et mondial à l'horizon 2000 Competition Between Different Fossil Energy Resources on the European and World Markets Between Now and the Year 2000

    Directory of Open Access Journals (Sweden)

    Brunner G.

    2006-11-01

    Full Text Available Le pétrole continuera à dominer la scène énergétique mondiale d'ici l'an 2000 mais sa part relative se réduira progressivement. Il est vraisemblable qu'il continuera a jouer son rôle de prix directeur de l'énergie. Le gaz naturel est actuellement lié dans son prix au fuel oil mais son prix de revient dépend de nombreux facteurs : coûts d'exploration, de transport de gestion de réseau et de stockage qu'il faudra prendre en considération pour assurer la rentabilité des investissements. Le charbon n'est pas compétitif pour une grande partie de sa production dans la Communauté et l'on ne doit guère s'attendre à ce que cette situation change totalement dans l'avenir. Hors d'Europe par contre, particulièrement aux USA, le charbon est tout à fait concurrentiel et d'ici l'an 2000 on doit s'attendre à une croissance considérable du commerce international vers l'Europe occidentale. En fait, nucléaire et charbon supplanteront le fuel oil et joueront des rôles complémentaires dans la production d'électricité mais le nucléaire gardera un avantage sur le thermique classique beaucoup moins protégé contre le risque de hausse des prix des combustibles. Les autres combustibles fossiles sont abondants mais leur production sera limitée en raison des coûts et des problèmes d'environnement. Oil will continue to dominate the world energy scene between now and the year 2000, but its relative share will gradually be reduced. It will probably continue ta play the role of price setter for energy. The price of natural gas is currently linked to that of fuel oil, but its cost price depends on various factors such as the costs of exploration, transportation, management of the network and storage, all of which must be taken into consideration in seeing that investments are profitable. Most of the cool produced in the EEC is not competitive, and this situation can hardly be expected to undergo a total change in the future. Outside of Europe, however, especially in the USA, cool is entirely competitive, and between now and the year 2000 we can expect a considerable increase in international trade toward Western Europe. Actually, nuclear energy and cool will take the place of fuel oil and will play complementary roles in electricity production, but nuclear energy will maintain on advantage over conventional thermal energy which is much less protected against the risk of rises in fuel prices. Other fossil fuels are abundant, but their production will be limited because of costs and environmentai problems.

  1. Focus 2012. Awakening into a new age - Elements of a sustainable energy supply. Ressource efficiency - key competency of sustainable societies, Sustainable chemistry - fundamental building blocks of a green economy. Annual report; Schwerpunkte 2012. Aufbruch ins neue Zeitalter - Elemente einer nachhaltigen Energieversorgung, Ressourceneffizienz - Schluesselkompetenz zukunftsfaehiger Gesellschaften, Nachhaltige Chemie - elementarer Baustein einer Green Economy. Jahrespublikation

    Energy Technology Data Exchange (ETDEWEB)

    Mavromati, Fotini; Ittershagen, Martin (comps.)

    2012-05-30

    The Federal Environmental Agency (Dessau-Rosslau, Federal Republic of Germany) sees excellent opportunities to move the economic regeneration forward by means of environmental protection. Under this aspect, the annual report ''Focus 2012'' under consideration presents the following contributions: (1) Green Economy as a new model for economic development; (2) Elements of a sustainable energy supply; (3) Resource efficiency as a key competence for sustainable societies; (4) Green Chemistry as a fundamental building block of Green Economy.

  2. Early Biological Evolution in Relation to Mineral and Energy Resources: Igcp Project 157 Évolution biologique précoce en relation avec des ressources énergétiques et minérales : projet 157 de l'IGPC

    Directory of Open Access Journals (Sweden)

    Oehler J. H.

    2006-10-01

    Full Text Available Project 157 of the International Geological Correlation Program is concerned with the timing of major events in biological history (such as the advent of bacterial sulfate reduction and the development of oxygen-releasing photosynthesis and how these events may have been related to the formation of mineral and fossil fuel deposits. Both direct and indirect forms of microbial involvement are being investigated. Examples of direct involvement would be contributions of sulfate-reducing bacteria to the formation of certain stratiform sulfide mineral deposits and massive accumulation of microbial remains to form bog head coals and oil shales. An example of indirect involvement would be photosynthetic oxygenation of the Proterozoic atmosphere providing conditions amenable to the formation of red bed copper deposits. Two aspects of Project 157 are directly applicable to the search for petroleum reserves. One is the subproject thut deals with pre-Devonian crude oils; a major conclusion of our work in this area is that many Proterozoic sedimentary sequences have oil and gas potential and should not be neglected by explorationists. The other is the subproject that deals with organic diagenesis of modern microbial mat communities; among other things, work in this area should lead to the recognition of new biological tracer compounds that can be used for oil-to-source correlations. Le projet 157 du Programme International de Corrélations Géologiques concerne le déroulement dans le temps des événements majeurs de l'histoire biologique (comme l'apparition de la réduction bactérienne des sulfates et le développement de la photosynthèse productive d'oxygène et comment ces événements sont en relation avec la formation de minerais et de combustibles fossiles. On étudie les actions microbiologiques directes ou indirectes. Des exemples d'actions directes peuvent être le rôle des bactéries réductrices des sulfates dans la formation de minerais sulfurés stratiformes et dans l'accumulation massive de restes microbiologiques pour former des charbons boghead et des schistes à huiles. Un exemple d'action indirecte serait l'oxygénation photo-synthétique de l'atmosphère protérozoïque donnant des conditions favorables à la formation de couches rouges à cuivre. Deux aspects du projet 157 sont directement applicables à la recherche de réserves de pétrole. L'un est le sous-projet qui s'occupe des huiles brutes pré-dévoniennes. Une des conclusions principales de nos travaux dans ce domaine est que beaucoup de séries sédimentaires protérozoïques ont un potentiel en huile et en gaz et ne doivent pas être négligées par les explorateurs. L'autre aspect est un sous-projet qui traite de la diagenèse organique des communautés de mattes microbiologiques actuelles. Parmi d'autres résultats, les travaux dans ce domaine peuvent conduire à l'identification de nouveaux indicateurs biologiques utilisables pour les corrélations entre l'huile et les roches mères.

  3. sodium

    International Development Research Centre (IDRC) Digital Library (Canada)

    Les initiatives de réduction de la consommation de sel qui visent l'ensemble de la population et qui ciblent la teneur en sodium des aliments et sensibilisent les consommateurs sont susceptibles de réduire la consommation de sel dans toutes les couches de la population et d'améliorer la santé cardiovasculaire. Ce projet a ...

  4. Prevalence de l'infection a VIH chez les patients victimes d'un ...

    African Journals Online (AJOL)

    Introduction: Le VIH/SIDA et son traitement antirétroviral sont associés à un risque élevé de maladies cardiovasculaires comme les accidents vasculaires cérébraux (AVC). L'objectif de cette étude était d'estimer la prévalence du VIH et d'identifier ses facteurs associés chez les patients hospitalisés pour un AVC. Méthode: ...

  5. Réduction de la consommation de sel dans l'ensemble de la ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    tante cause d'hypertension, laquelle augmente les risques de maladies cardiovasculaires, renales et de décès. Des ini- tiatives nationales visant à réduire la consommation de sel peuvent améliorer la tension artérielle au niveau de l'ensem- ble de la population. Cependant, plusieurs défis subsistent afin de réduire la ...

  6. IDRA 2016 IDRC Thematic Priorities Word doc_FR

    International Development Research Centre (IDRC) Digital Library (Canada)

    Carole Labrie

    chroniques liées aux aliments (comme l'hypertension, le diabète et les maladies cardiovasculaires); prévenir et réduire les risques de maladie liés aux pandémies et aux maladies infectieuses émergentes, et le risque de maladie lié au tabac. 2) Économies inclusives. Le domaine thématique Économies inclusives investit ...

  7. Case series

    African Journals Online (AJOL)

    raoul

    18 janv. 2012 ... d'asthme, d'une affection cardiaque préexistante (valvulopathie ou une autre atteinte), de prise d'anorexigènes. Nous avons en outre apprécié les données cliniques (dont les signes fonctionnels cardio-vasculaires, dermatologiques), les signes généraux (constantes hémodynamiques, état général), les ...

  8. Faible taux de succes du sevrage tabagique a court et moyen termes au decours d�un infarctus aigu du myocarde dans un service de cardiologie de Dakar au Senegal

    Directory of Open Access Journals (Sweden)

    Alassane Mbaye

    2011-10-01

    Full Text Available e le tabac pendant l�hospitalisation. Apres un suivi de 3 mois, 45% des patients ont repris le tabac, 65% a 6 mois et 85% a 12 mois. CONCLUSION: Le tabagisme est assez frequent chez les patients senegalais presentant un infarctus du myocarde. Le taux de sevrage tabagique a court et moyen termes est faible. Le sevrage tabagique devrait alors constituer un objectif privilegie dans la prevention des maladies cardio-vasculaires.

  9. Prévalence, facteurs associés et prédisposant au syndrome ...

    African Journals Online (AJOL)

    Introduction: Le syndrome métabolique est associé aux maladies cardiovasculaires. L'infection au VIH est devenue aujourd'hui une maladie chronique. L'objectif de cette étude est de déterminer la prévalence, les facteurs associés et prédisposant au syndrome métabolique chez les patients infectés par le VIH sous ...

  10. Triglycéridémie postprandiale, insulinémie, leptinémie et distribution des apolipoprotéines CIII entre TGRL et HDL chez l’homme normolipidémique

    Directory of Open Access Journals (Sweden)

    Le Roy Brigitte

    2002-07-01

    Full Text Available Notre article, publié en 1998 dans OCL sur la « Leptine, épuration et utilisation postprandiales des lipides chez l’homme », faisait état pour la première fois d’un lien entre cette hormone produite par le tissu adipeux et le risque de maladies cardiovasculaires lié à un défaut d’épuration des lipides en période postprandiale.

  11. Short communication

    African Journals Online (AJOL)

    abp

    15 mai 2013 ... cardiovasculaire, 55% étaient hypertendus, alors que 6,4% avaient des troubles cognitifs. Les sujets âgés en hémodialyse chronique représentent une population de patients fragiles. Ils nécessitent une surveillance particulière et régulière afin de prévenir certaines complications propres au sujet âgé et ...

  12. Case report

    African Journals Online (AJOL)

    abp

    17 nov. 2017 ... diminué compte tenu de la prise en charge médicale plus agressive diminuant la fréquence à 0.2%, cependant la mortalité reste très élevée [2]. C'est une urgence extrême imposant une prise en charge multidisciplinaire associant les urgentistes, les cardiologues et les chirurgiens cardiovasculaires.

  13. Virksomhedens personalearbejde

    DEFF Research Database (Denmark)

    Virksomhedens personalearbejde er et tema som dækker over forskellige tilgange til ledelse og administration af de menneskelige ressourcer i organisationen. Både den personaleadministrative tilgang og Human Ressource Management (HRM) - tilgangen præsenteres i bogen. Et af hovedsynspunkterne i bogen...... er, at der ikke findes generelle principper for ledelse og administration af de menneskelige ressourcer i den enkelte organisation. Bogens ide er at samle udvalgte centrale emner med relevans for virksomhedens personalearbejde i praksis. Følgende emner behandles: Virksomhedens personalearbejde i...

  14. L’intégration du capital humain dans un outil de pilotage de la performance : le cas du tableau de bord stratégique

    OpenAIRE

    Borchani, Manel; Cheffi, Walid

    2005-01-01

    Cette communication examine comment un outil de contrôle de gestion, le tableau de bord stratégique (TdB), permet-il d’intégrer le capital humain dans le pilotage de la performance globale de l’entreprise ? La théorie des ressources (resource based view theory) considère que les Ressources Humaines (RH) sont des ressources internes précieuses pour l’entreprise. Cette théorie établit un lien entre elles, les compétences distinctives et l’avantage concurrentiel durable de l’entreprise. Un tel a...

  15. Theoretical interpretations and experimental verifications of a radioelectric resonance method for measuring the electronic density and collision frequency in a discharge plasma in gases; Interpretations theoriques et verifications experimentales d'une methode de resonance radioelectrique pour la mesure de la densite d'une decharge dans les gaz

    Energy Technology Data Exchange (ETDEWEB)

    Nguyen Trong, Khoi [Commissariat a l' Energie Atomique, Saclay (France).Centre d' Etudes Nucleaires

    1960-07-01

    Theoretical discussions and experimental verifications of one radioelectric resonance method for measuring plasma electronic density and collision frequency. (author) [French] Discussions theoriques et verifications experimentales sur une methode de resonance radioelectrique pour la mesure de la densite electronique et de la frequence de collision d'un plasma d'une decharge dans le gaz. (auteur)

  16. Journal des Sciences Pour l'Ingénieur - Vol 12 (2010)

    African Journals Online (AJOL)

    DOWNLOAD FULL TEXT DOWNLOAD FULL TEXT. M Pasquinelli, D Maestre, K Lagha, D Barakel, J Le Rouzo, C Alfonso, O Palais ... Modele electrique d'une pile a combustible « pem » pour utilisation electronique de puissance · EMAIL FULL TEXT EMAIL FULL TEXT DOWNLOAD FULL TEXT DOWNLOAD FULL TEXT.

  17. RF sources for recent linear accelerator projects

    International Nuclear Information System (INIS)

    Terrien, J.C.; Faillon, G.; Guidee, P.

    1992-01-01

    We present the state of the art of high power klystrons at Thomson Tubes Electroniques, along with the main technological limitations for peak power and pulse width. Then we describe the work that is under way to upgrade performance and some of the alternative RF sources that have been developed. (Author) 3 refs., 4 figs., 2 tabs

  18. Author Details

    African Journals Online (AJOL)

    Meddereg, AW. Vol 9, No 2 (1999) - Articles Solution Gestion Electronique de Document pour l'archivage des manuscrits. Abstract. ISSN: 1111-0015. AJOL African Journals Online. HOW TO USE AJOL... for Researchers · for Librarians · for Authors · FAQ's · More about AJOL · AJOL's Partners · Terms and Conditions of Use ...

  19. Tüür, Erkki-Sven: Crystallisatio. Requiem / Pierre Gervasoni

    Index Scriptorium Estoniae

    Gervasoni, Pierre

    1996-01-01

    Uuest heliplaadist "Tüür, Erkki-Sven: Crystallisatio. Requiem. Architectonics VI. Passion. Illusion. E.-S. Tüür (electronique en direct), Kaia Urb (soprano), Tiit Kogermann (tenor), Choeur de chambre Philharmonique d'Estonie, Orchestre de chambre de Tallinn, Tõnu Kaljuste. ECM New Series ECM 1590, distribution Polygram 449 459-2 (CD:158 F)

  20. International conference on signals and images in medicine and biology (BIOSIGMA 78), Paris, 24-28 April 1978. Colloque international sur les signaux et les images en medecine et en biologie (BIOSIGMA 78), Paris, 24-28 avril 1978

    Energy Technology Data Exchange (ETDEWEB)

    1978-01-01

    Proceedings of an important international colloquium organized by the SEE (Societe des Electriciens, des Electroniciens et des Radioelectriciens) and the GIEL (Groupement des Industries Electroniques) are presented. The aim of this meeting is the development of biomedical techniques, specially, in the fields of nuclear medicine and medical electronic and computer equipment.

  1. Nuclear electronic equipment for control and monitoring boards. MCH/MENT Recommendations

    International Nuclear Information System (INIS)

    Roquefort, H.

    1975-01-01

    The constitution of the group ''Materiel de Controle Homologue - Materiel Electronique Nucleaire pour Tableaux de controle et de commande'' is given. This group has to define, work out, and propose general and particular specifications related to reactor control-board instrumentation. These specifications are useful in France and abroad. Published documents are listed [fr

  2. The electron diffraction: a prime technique to characterize the behaviour of the Li{sub 1-x}C{sub y} / Li{sub x}NiO{sub 2} positive electrode; La diffraction electronique: une technique de choix pour caracteriser le comportement de l`electrode positive Li{sub 1-x}C{sub y} / Li{sub x}NiO{sub 2}

    Energy Technology Data Exchange (ETDEWEB)

    Peres, J.P.; Delmas, C.; Weill, F. [Centre National de la Recherche Scientifique (CNRS), 33 - Pessac (France). Institut de Chimie de la Matiere Condensee de Bordeaux; Broussely, M.; Perton, F.; Biensan, Ph. [SAFT, Advanced and Industrial Battery Group, 86 - Poitiers (France); Willmann, P. [Centre National d`Etudes Spatiales (CNES), 31 - Toulouse (France)

    1996-12-31

    LiNiO{sub 2} is one of the most promising material for positive electrodes of lithium-ion batteries. However, its behaviour during cycling and the existence of several phase transitions induced by the lithium ions de-intercalation process has not been explained so far. A transition electron microscopy study of various Li{sub x}NiO{sub 2} (0.25

  3. Experiment search of the electroweak symmetry breaking in the H {yields} {gamma}{gamma} channel and of a solution of the hierarchy problem in the Atlas experiment: participation to the tests of the electronics of the electromagnetic calorimeter; Recherche experimentale de la brisure spontanee de symetrie electrofaible dans le canal H {yields} {gamma}{gamma} et d'une solution au probleme de hierarchie dans ATLAS. Participation a la preparation de l'electronique du calorimetre electromagnetique

    Energy Technology Data Exchange (ETDEWEB)

    Escalier, M

    2005-04-15

    This thesis deals with the understanding of the spontaneous electroweak symmetry breaking mechanism in the ATLAS experiment at LHC collider, by studying two complementary topics: the search for the Higgs boson in the H {yields} {gamma}{gamma} channel, and a search for extra dimensions in the gluon sector. Tests of the electronic of the electromagnetic calorimeter allowed us to validate various cards that were under the responsibility of the LPNHE. Using full simulation data of the detector allowed us to precisely compute mass resolution of the di-photon system. Due to recent theoretical improvements, signal and background have been studied at the next order of the perturbative development, which increases cross-sections. With regards to the jet background, a study has been done using discriminating variables in order to obtain, for a 80 % photons efficiency, a rejection factor of 7000. The discovery potential benefits from this change of cross-sections and increases by 50 % in comparison with the same analysis done at the leading order. In addition to this, a new analysis using a maximum likelihood method allowed us to increase by 40 % the discovery potential in comparison with our classical analysis. In conclusion, the Higgs boson of 120 GeV/c{sup 2} can be now discovered in this channel with an integrated luminosity of 10 fb{sup -1}. Furthermore, the consistency of the problem of the Higgs boson mass can be solved by introducing extra dimensions in which gluons can propagate. We have shown that it was possible to discover extra-dimensions up to a compactification scale of 15 TeV. (author)

  4. Electron paramagnetic resonance study of radicals formed by radiolysis at 77 K of nitroalkanes and of their solutions in organic glasses. Chromatography analysis of radiolysis products of nitromethane in ethanol solution in a vitreous medium; Etude par resonance paramagnetique electronique des radicaux formes par radiolyse a 77 K des nitroalcanes et de leurs solutions dans les verres organiques analyse par chromatographie des produits de la radiolyse du nitromethane en solution dans l'ethanol en milieux vitreux

    Energy Technology Data Exchange (ETDEWEB)

    Rosilio, C [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1968-05-01

    With a view to explaining the formation of the final products resulting from the photolysis and the radiolysis of nitro-alkanes, we have attempted to identify the paramagnetic species formed as intermediates during the radiolysis. Our work has covered the structure and the reactivity of the radicals formed by 7 irradiation of the nitrogen containing derivatives at 77 K, and on the mechanism of formation and of disappearance of these radicals in the various matrices used. The radicals resulting from the removal of a hydrogen atom in the {alpha} position of the NO{sub 2} group, and the radicals resulting from addition reactions on the nitrogen group characterized by an unpaired electron on the nitrogen have been identified, either during the radiolysis of pure nitroalkanes, or during the radiolysis of nitro-alkanes in solution in organic glasses at 77 K. A study has been made of the conformation and the movements of radicals in the matrices, and the mechanism of formation of the observed radicals produced generally by the capture by the nitro-alkanes of primary radiolysis species. The nitro-alkanes in ethanol solution can behave as traps both for electrons and for free radicals. The study of the radiolysis of nitro-alkanes in solution in a polar ethanol glass has been completed with chemical analyses on the final radiolysis products; it has been possible to deduce the capture efficiency of trapped electrons and of free radicals by nitro-alkanes in ethanol. For this we have determined the radio-chemical yields of hydrogen, acetaldehyde and glycol as a function of the capture agent concentration, for the nitro-methane-ethanol system. A mechanism for the disappearance of the observed radicals is proposed. (author) [French] Dans le but d'expliquer la formation des produits finals formes au cours de la photolyse et la radiolyse des nitroalcanes, nous nous sommes proposes d'identifier les especes paramagnetiques se formant intermediairement au cours de la radiolyse. Notre etude porte sur la structure et la reactivite des radicaux formes par irradiation 7 des derives nitres a 77 K, et sur le mecanisme de formation et de disparition de ces radicaux dans les differentes matrices utilisees. Les radicaux resultant de l'arrachement d'un hydrogene en {alpha} du groupe NO{sub 2}, et les radicaux resultant de reactions d'addition sur le groupe nitre caracterises par un electron non apparie sur l'azote ont ete identifies, soit dans la radiolyse des nitroalcanes purs, soit dans la radiolyse a 77 K des nitroalcanes en solution dans les verres organiques. La conformation et les mouvements des radicaux dans les matrices, le mecanisme de formation des radicaux observes resultant generalement de la capture par les nitroalcanes des especes primaires de la radiolyse ont ete etudies. Les nitroalcanes en solution dans l'ethanol se manifestent a la fois comme capteurs d'electrons et de radicaux libres. L'etude de la radiolyse des nitroalcanes en solution dans un verre polaire d'ethanol a ete completee par des analyses chimiques des produits finals de la radiolyse; elle nous a permis de deduire l'efficacite de capture des electrons pieges et des radicaux libres par les nitroalcanes dans l'ethanol. Pour cela nous avons dose, pour le systeme nitro-methane - ethanol les rendements radiochimiques de-l'hydrogene, de l'acetaldehyde et du glycol en fonction de la concentration en capteur. Un mecanisme de disparition des radicaux observes a ete propose. (auteur)

  5. Use of the statistical control of processes through checking before treatment realised with the ionization chamber and by electronic portal system of imaging (E.P.I.D.) in intensity modulated radiotherapy (I.M.R.T.); Utilisation de la maitrise statistique des processus dans le cadre des controles avant traitement realises avec la chambre d'ionisation et par systeme d'imagerie portale electronique (EPID) en radiotherapie conformationnelle avec modulation d'intensite (RCMI)

    Energy Technology Data Exchange (ETDEWEB)

    Villani, N.; Gerard, K.; Noel, A. [Nancy univ., Lab. de Recherche en Radiophysique, CRAN UMR 7039, CNRS, Centre Alexis-Vautrin, 54 - Vandoeuvre-les-Nancy (France); Marchesi, V.; Huger, S. [Centre Alexis-Vautrin, Unite de Radiophysique Medicale, 54 - Vandoeuvre-les-Nancy (France)

    2009-10-15

    The expected results are to demonstrate that it is possible to reduce the times devoted to the pre-treatment controls, while keeping an optimal safety, on substituting the measures of the ionization chamber by this one of the electronic portal imaging device (E.P.I.D.). (N.C.)

  6. Electronic and magnetic properties study of neptunium compounds: NpX{sub 3} and Np{sub 2}T{sub 2}X by Moessbauer effect, neutrons diffraction and Squid magnetometry; Etude des proprietes magnetiques et electroniques de composes de neptunium NpX{sub 3} et Np{sub 2}T{sub 2}X par spectrometrie mossbauer, diffraction de neutrons et magnetometrie squid

    Energy Technology Data Exchange (ETDEWEB)

    Colineau, E.

    1996-07-11

    This work is a contribution to the study of magnetic and electronic properties of the intermetallic compounds: NpX{sub 3} (X= Al, Ga, In, Sn) and Np{sub 2}T{sub 2}X (T= Co, Ni, Ru, Rh, Pd, Pt; X= In, Sn). These properties have been determined by Moessbauer effect, neutron diffraction and Squid magnetometry. The obtained results for NpX{sub 3} show particularly that NpAl{sub 3} orders in a type II (k= 1/2 1/2 1/2) antiferromagnetic structure at T{sub N} {approx_equal} 37 K. The antiferromagnetic phase NpGa{sub 3} orders in a type II too and the magnetic moments carried by neptunium in the ferromagnetic phase are oriented along the (111) axes. The two NpIN{sub 3} magnetic phases observed by Moessbauer effect (4.2 K-10 K and 10 K- 14 K) are identified by neutron diffraction as ferromagnetic and antiferromagnetic (k= 3/8 3/8 3/8). In this last phase the moments are oriented along the (111) axes. The magnetization measures on monocrystals show a weak anisotropy with (111) at all the temperatures and reveal the presence of a third magnetic phase between 8.2 and 10 K. At last, the fundamental state of the compounds NpAl{sub 3}, NpGa{sub 3} and NpIn{sub 3} is attributed to the {Gamma}{sub 5} crystal field and the strong reduction of the ordered moment in NpSn{sub 3} to a Kondo effect. Concerning the Np{sub 2}T{sub 2}X compounds, the Moessbauer effect measures have revealed that eight of these compounds order and three do not order. (O.M.). 239 refs.

  7. RIFIFI: Analytical calculation method of the critical condition and flux in a varied regions reactor by two-group theory and one dimension developed for the Mercury-Ferranti computer; Rififi: methode de calcul analytique de la condition critique et des flux d'une pile a regions variees en theorie a deux groupes et a une dimension programmee pour le calculateur electronique Mercury (Ferranti)

    Energy Technology Data Exchange (ETDEWEB)

    Amouyal, A; Bacher, P; Lago, B; Mengin, F L; Parker, E [Commissariat a l' Energie Atomique, Saclay (France).Centre d' Etudes Nucleaires

    1960-07-01

    The calculation method presented in this report has been developed for the Mercury-Ferranti computer of the C.E.N.S. This calculation method allows to resolve the diffusion equations and continuity equations of flux and flow with two groups of neutrons and one dimension in spherical, cylindrical and linear geometry. In the cylindrical and linear configurations, we can take the height and extrapolated radius into account. The critical condition can be realised by varying linearly one or more parameters: k{sub {infinity}}, medium frontier, height or extrapolated radius. The calculation method enables also to calculate the flux, adjoint flux and various integrals. In the first part, it explains what is needed to know before using the method: data presentation, method possibilities, results presentation with some information about restrictions, accuracy and calculation time. The complete formulation of the calculation method is given in the second part. (M.P.)

  8. Electron paramagnetic resonance study of radicals formed by radiolysis at 77 K of nitroalkanes and of their solutions in organic glasses. Chromatography analysis of radiolysis products of nitromethane in ethanol solution in a vitreous medium; Etude par resonance paramagnetique electronique des radicaux formes par radiolyse a 77 K des nitroalcanes et de leurs solutions dans les verres organiques analyse par chromatographie des produits de la radiolyse du nitromethane en solution dans l'ethanol en milieux vitreux

    Energy Technology Data Exchange (ETDEWEB)

    Rosilio, C. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1968-05-01

    With a view to explaining the formation of the final products resulting from the photolysis and the radiolysis of nitro-alkanes, we have attempted to identify the paramagnetic species formed as intermediates during the radiolysis. Our work has covered the structure and the reactivity of the radicals formed by 7 irradiation of the nitrogen containing derivatives at 77 K, and on the mechanism of formation and of disappearance of these radicals in the various matrices used. The radicals resulting from the removal of a hydrogen atom in the {alpha} position of the NO{sub 2} group, and the radicals resulting from addition reactions on the nitrogen group characterized by an unpaired electron on the nitrogen have been identified, either during the radiolysis of pure nitroalkanes, or during the radiolysis of nitro-alkanes in solution in organic glasses at 77 K. A study has been made of the conformation and the movements of radicals in the matrices, and the mechanism of formation of the observed radicals produced generally by the capture by the nitro-alkanes of primary radiolysis species. The nitro-alkanes in ethanol solution can behave as traps both for electrons and for free radicals. The study of the radiolysis of nitro-alkanes in solution in a polar ethanol glass has been completed with chemical analyses on the final radiolysis products; it has been possible to deduce the capture efficiency of trapped electrons and of free radicals by nitro-alkanes in ethanol. For this we have determined the radio-chemical yields of hydrogen, acetaldehyde and glycol as a function of the capture agent concentration, for the nitro-methane-ethanol system. A mechanism for the disappearance of the observed radicals is proposed. (author) [French] Dans le but d'expliquer la formation des produits finals formes au cours de la photolyse et la radiolyse des nitroalcanes, nous nous sommes proposes d'identifier les especes paramagnetiques se formant intermediairement au cours de la radiolyse. Notre etude porte sur la structure et la reactivite des radicaux formes par irradiation 7 des derives nitres a 77 K, et sur le mecanisme de formation et de disparition de ces radicaux dans les differentes matrices utilisees. Les radicaux resultant de l'arrachement d'un hydrogene en {alpha} du groupe NO{sub 2}, et les radicaux resultant de reactions d'addition sur le groupe nitre caracterises par un electron non apparie sur l'azote ont ete identifies, soit dans la radiolyse des nitroalcanes purs, soit dans la radiolyse a 77 K des nitroalcanes en solution dans les verres organiques. La conformation et les mouvements des radicaux dans les matrices, le mecanisme de formation des radicaux observes resultant generalement de la capture par les nitroalcanes des especes primaires de la radiolyse ont ete etudies. Les nitroalcanes en solution dans l'ethanol se manifestent a la fois comme capteurs d'electrons et de radicaux libres. L'etude de la radiolyse des nitroalcanes en solution dans un verre polaire d'ethanol a ete completee par des analyses chimiques des produits finals de la radiolyse; elle nous a permis de deduire l'efficacite de capture des electrons pieges et des radicaux libres par les nitroalcanes dans l'ethanol. Pour cela nous avons dose, pour le systeme nitro-methane - ethanol les rendements radiochimiques de-l'hydrogene, de l'acetaldehyde et du glycol en fonction de la concentration en capteur. Un mecanisme de disparition des radicaux observes a ete propose. (auteur)

  9. The electron diffraction: a prime technique to characterize the behaviour of the Li{sub 1-x}C{sub y} / Li{sub x}NiO{sub 2} positive electrode; La diffraction electronique: une technique de choix pour caracteriser le comportement de l`electrode positive Li{sub 1-x}C{sub y} / Li{sub x}NiO{sub 2}

    Energy Technology Data Exchange (ETDEWEB)

    Peres, J P; Delmas, C; Weill, F [Centre National de la Recherche Scientifique (CNRS), 33 - Pessac (France). Institut de Chimie de la Matiere Condensee de Bordeaux; Broussely, M; Perton, F; Biensan, Ph [SAFT, Advanced and Industrial Battery Group, 86 - Poitiers (France); Willmann, P [Centre National d` Etudes Spatiales (CNES), 31 - Toulouse (France)

    1997-12-31

    LiNiO{sub 2} is one of the most promising material for positive electrodes of lithium-ion batteries. However, its behaviour during cycling and the existence of several phase transitions induced by the lithium ions de-intercalation process has not been explained so far. A transition electron microscopy study of various Li{sub x}NiO{sub 2} (0.25

  10. Experiment search of the electroweak symmetry breaking in the H {yields} {gamma}{gamma} channel and of a solution of the hierarchy problem in the Atlas experiment: participation to the tests of the electronics of the electromagnetic calorimeter; Recherche experimentale de la brisure spontanee de symetrie electrofaible dans le canal H {yields} {gamma}{gamma} et d'une solution au probleme de hierarchie dans ATLAS. Participation a la preparation de l'electronique du calorimetre electromagnetique

    Energy Technology Data Exchange (ETDEWEB)

    Escalier, M

    2005-04-15

    This thesis deals with the understanding of the spontaneous electroweak symmetry breaking mechanism in the ATLAS experiment at LHC collider, by studying two complementary topics: the search for the Higgs boson in the H {yields} {gamma}{gamma} channel, and a search for extra dimensions in the gluon sector. Tests of the electronic of the electromagnetic calorimeter allowed us to validate various cards that were under the responsibility of the LPNHE. Using full simulation data of the detector allowed us to precisely compute mass resolution of the di-photon system. Due to recent theoretical improvements, signal and background have been studied at the next order of the perturbative development, which increases cross-sections. With regards to the jet background, a study has been done using discriminating variables in order to obtain, for a 80 % photons efficiency, a rejection factor of 7000. The discovery potential benefits from this change of cross-sections and increases by 50 % in comparison with the same analysis done at the leading order. In addition to this, a new analysis using a maximum likelihood method allowed us to increase by 40 % the discovery potential in comparison with our classical analysis. In conclusion, the Higgs boson of 120 GeV/c{sup 2} can be now discovered in this channel with an integrated luminosity of 10 fb{sup -1}. Furthermore, the consistency of the problem of the Higgs boson mass can be solved by introducing extra dimensions in which gluons can propagate. We have shown that it was possible to discover extra-dimensions up to a compactification scale of 15 TeV. (author)

  11. Conservation through payments for an ecosys- tem service?

    African Journals Online (AJOL)

    tem service? In his Spotlights ... functions” and “ecosystem services” are being ridiculed by the developments in ... high price as legal marketing would avoid various middlemen. ... Diagnostic participatif de la gestion des ressources naturelles.

  12. PM A-37Tap.pmd

    African Journals Online (AJOL)

    PC1

    control. In western Senegal Sine Saloum Region, lowlands salinity is due to sea contact. ... et Gestion des Ressources Naturelles au Sine-. Saloum ...... en mesure de dire que : - les sols des bas ... determinants of irrigated rice performance in.

  13. Etude de la dynamique de la macrofaune du sol en culture d'ognon

    African Journals Online (AJOL)

    Département Gestion des Ressources Naturelles/Système de Production,. 01 BP 470 ... Agricultural Research and Training of the Institute of the Environment and Agricultural Research (INERA). The objective was to ...... Ecotoxicology and.

  14. : tous les projets | Page 517 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    amélioration des cultures et de gestion des ressources naturelles sont compromises. Date de début : 30 ... Sujet: WATER SHORTAGE, CLIMATE CHANGE, ADAPTATION TO CHANGE, DISASTER PREPAREDNESS. Région: Burkina Faso, Ivory Coast, ...

  15. tunisia

    African Journals Online (AJOL)

    lanez

    31 déc. 2014 ... l'absence des ressources fourragères, à cause des ressources en eau généralement limitées tant quantitativement ... (Réseau de Distribution d'eau potable et Sondages), alors que 10% des eaux (Citernes) sont sales, à cause de .... éleveurs assurent la désinfection des trayons après la traite (Figure 2).

  16. ferroukhi bedrani

    African Journals Online (AJOL)

    Administrateur

    (Wilaya de Médéa). Le financement de l'enquête provient du Centre de recherche en économie appliquée au développement (CREAD). Les enquêteurs ont ... concept: 1.1.1 - Pauvreté en termes de ressources. La pauvreté pourrait être interprétée comme un manque de ressources monétaires, une insuffisance des biens ...

  17. 2- Ngodi.pmd

    African Journals Online (AJOL)

    chifaou.amzat

    19 oct. 2011 ... connaître la part des ressources qui seraient nécessaires pour extraire tous les pauvres de leur situation par le biais des transferts de liquidités parfaitement ciblés. Concrètement, la profondeur de la pauvreté permet d'évaluer les ressources nécessaires pour éradiquer la pauvreté, dans le cas d'un ciblage.

  18. 1314-IJBCS-Article-Ngom Daouda

    African Journals Online (AJOL)

    KODJIO NORBERT

    en fourrage et les potentialités écologiques des parcours, constitue le principal problème qui entrave la gestion durable des ressources sylvopastorales. La présente étude se propose de caractériser les ressources herbagères de la réserve de biosphère du Ferlo. Il s'agira d'établir le cortège floristique et d'évaluer la.

  19. 1699-IJBCS-Article- Matias Fonteh

    African Journals Online (AJOL)

    hp

    Gestion intégrée des ressources en eau dans le bassin versant du lac ... En prélude à l'élaboration d'une stratégie de gestion durable de l'eau du ..... dynamique des ressources en eau à l'échelle ... régulièrement les contrôles de la qualité.

  20. Management Models of Forest Resources in the Atlas Mountain ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    31 mars 2009 ... Expérimentation Participative et Adaptative de Modèles de Gestion des Ressources Forestières dans la Chaine Montagneuse de l'Atlas (Algérie, Maroc, Tunisie). Téléchargez le PDF. Rapports. Expérimentation Participative et Adaptative de Modèles de Gestion des Ressources Forestières dans la Chaine ...

  1. One More Thing

    DEFF Research Database (Denmark)

    Schultz, Majken

    2014-01-01

    Virksomheder kan bruge historien til at være kraftfulde ressourcer for innovation og række langt ind i fremtiden. Tim Cook og Apple viste – igen – vejen ved præsentationen af det nye ur.......Virksomheder kan bruge historien til at være kraftfulde ressourcer for innovation og række langt ind i fremtiden. Tim Cook og Apple viste – igen – vejen ved præsentationen af det nye ur....

  2. Contrôleur Régional (h/f) | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    En collaboration avec la Division des ressources humaines, administrer, mettre en œuvre et évaluer des règlements administratifs, des systèmes, des contrôles et des services reliés à tous les aspects de la gestion des ressources humaines au bureau régional, ce qui comprend le recrutement, la classification et la ...

  3. 195 Evaluation de la charge polluante des rivières des eaux usées ...

    African Journals Online (AJOL)

    kapepula

    ressources financières des pouvoirs publics au niveau local et l'absence de réelles politiques environnementales sont parmi les ... sont collectés vers les quatre rivières. Généralement les aides de la gestion des déchets adéquates protègent la santé humaine et l'environnement et conserve les ressources naturelles [3].

  4. Agriculture et environnement | Page 7 | CRDI - Centre de ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Guide des promesses des ressources génétiques aquatiques merveilleusement écrit et dont on avait grand besoin […] plein de conseils importants sur des façons de réaliser le potentiel de ressources génétiques aquatiques peu appréciées et souvent malmenées. – Thomas Lovejoy (Président, Heinz Center for Science, ...

  5. Mineral Taxation Policies in Developing Countries: An Application of Resource Rent Tax (L'imposition des ressources dans les pays en développement: application du concept de taxe sur la rente minière) (Políticas de impuestos a los minerales en los países en desarrollo: Aplicación del impuesto a la renta de recursos)

    OpenAIRE

    Keith F. Palmer

    1980-01-01

    The central problem of mineral taxation policy in developing countries is to establish a stable fiscal framework that, under conditions of uncertainty, both obtains a high share of mineral rent for the resource-owning country and ensures for the investor the prospect of a return on his investment commensurate with his risk. The main concern of the paper is to propose a practical fiscal framework, based on the resource rent tax concept, that meets these objectives. The resource rent tax is a p...

  6. Anomalies échocardiographiques chez l'hémodialysé chronique: prévalence et facteurs de risqué

    OpenAIRE

    Ezziani, Mariam; Najdi, Adil; Mikou, Souad; Elhassani, Anis; Akrichi, Mohammed Amine; Hanin, Hakim; Arrayhani, Mohammed; Houssaini, Tarik Sqalli

    2014-01-01

    Introduction Les complications cardio-vasculaires sont la principale cause de mortalité et de morbidité chez les patients hémodialysés chroniques. Le but de cette étude est de décrire les différentes atteintes cardiaques à l’échocardiographie transthoracique et de dégager les facteurs associés aux principales atteintes. Méthodes Etude transversale monocentrique incluant des patients adultes hémodialysés depuis plus d'un an et ayant bénéficié d'une échocardiographie transthoracique durant l'an...

  7. Possibility of applying the gamma-gamma method to the in situ determination of uranium-ore densities; Les possibilites d'application de la methode gamma-gamma a la determination en place de la densite des minerais d'uranium

    Energy Technology Data Exchange (ETDEWEB)

    Czubek, J; Guitton, J [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1965-07-01

    The principles of the gamma-gamma method are reviewed. It is shown in particular that, under certain conditions, the method makes it possible to obtain a representative measurement of the electronic density. Chemical analyses have been carried out on samples obtained from uranium deposits. The results show that an exact correlation exists between the massive and electronic densities. It is possible to consider the possibility of measuring the density of uranium-containing rocks by the gamma-gamma method. (authors) [French] Les principes de la methode gamma-gamma sont rappeles. En particulier, il est montre que, dans certaines conditions, la methode permet une mesure representative de la densite electronique. Des analyses chimiques ont ete effectuees sur des echantillons provenant de gisements uraniferes. Les resultats indiquent qu'il existe une correlation precise entre leur densite massique et leur densite electronique. Il est possible d'envisager la mesure de la densite des roches uraniferes par la methode gamma-gamma.

  8. Browse Title Index

    African Journals Online (AJOL)

    Vol 1, No 1 (2001), Mise en évidence d'un optimum de fines dans les sables ô béton: Exemple d'un sable des dunes de la région de Dakar ( Sénégal), Abstract. IK Cissé, M ... Vol 12 (2010), Modele electrique d'une pile a combustible « pem » pour utilisation electronique de puissance, Abstract. I Sadli, S Raël, B Davat, ...

  9. Gestion des déchets d'équipements électriques et électroniques ...

    African Journals Online (AJOL)

    La gestion des Déchets d'Equipements Electriques et Electroniques (DEEE) est un défi pour le Sénégal. Leur quantité augmente rapidement et leur gestion informelle expose l'environnement et les acteurs aux risques liés aux substances toxiques qu'ils contiennent. L'étude vise à déterminer les caractéristiques des ...

  10. R. F. plasmoids and resonant discharges; Plasmoides a haute frequence et decharges resonnantes

    Energy Technology Data Exchange (ETDEWEB)

    Taillet, J. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1964-06-15

    In R.F. discharges at reduced pressure a resonance can increase by an order of magnitude the intensity of the plasma R.F. electric field. The electron density of the plasma adjusts itself to keep the resonant frequency equal to the excitation frequency. This behaviour has been observed by an electron beam technique. When such a discharge is excited in electronegative gases, the negative ion density may be higher than the electron density. Therefore, the D.C. potential distribution in plasma and sheath is modified. The plasma appears as a luminous body isolated from the walls by a large sheath (R.F. plasmoid). (author) [French] Dans les decharges H.F. a faible pression une resonance peut elever d'un ordre de grandeur l'intensite du champ electrique interne du plasma. La densite electronique s'ajuste elle-meme de facon a rendre egales la frequence d'excitation et la frequence de la resonance. Ce mecanisme a ete observe a l'aide de faisceaux electroniques. Lorsqu'une telle decharge est excitee dans un gaz electronegatif, la densite des ions negatifs peut etre plus elevee, que la densite electronique, ce qui modifie la distribution du potentiel continu dans le plasma et la gaine. Le plasma apparait comme un corps lumineux isole des parois par une large gaine (plasmoide a haute frequence). (auteur)

  11. R. F. plasmoids and resonant discharges; Plasmoides a haute frequence et decharges resonnantes

    Energy Technology Data Exchange (ETDEWEB)

    Taillet, J [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1964-06-15

    In R.F. discharges at reduced pressure a resonance can increase by an order of magnitude the intensity of the plasma R.F. electric field. The electron density of the plasma adjusts itself to keep the resonant frequency equal to the excitation frequency. This behaviour has been observed by an electron beam technique. When such a discharge is excited in electronegative gases, the negative ion density may be higher than the electron density. Therefore, the D.C. potential distribution in plasma and sheath is modified. The plasma appears as a luminous body isolated from the walls by a large sheath (R.F. plasmoid). (author) [French] Dans les decharges H.F. a faible pression une resonance peut elever d'un ordre de grandeur l'intensite du champ electrique interne du plasma. La densite electronique s'ajuste elle-meme de facon a rendre egales la frequence d'excitation et la frequence de la resonance. Ce mecanisme a ete observe a l'aide de faisceaux electroniques. Lorsqu'une telle decharge est excitee dans un gaz electronegatif, la densite des ions negatifs peut etre plus elevee, que la densite electronique, ce qui modifie la distribution du potentiel continu dans le plasma et la gaine. Le plasma apparait comme un corps lumineux isole des parois par une large gaine (plasmoide a haute frequence). (auteur)

  12. Comment financer l'allocation universelle. La stratégie de Van Parijs (1995) en question

    OpenAIRE

    Claude Gamel

    2004-01-01

    Dans l'ouvrage que Van Parijs a consacré en 1995 aux fondements philosophiques et économiques du projet d'allocation universelle, le chapitre IV est dédié au problème du financement « soutenable » d'une telle mesure. Les « rentes d'emploi » y sont présentées comme un troisième type de ressources susceptibles d'élargir l'assiette fiscale du financement, à côté des « ressources externes » et des « ressources internes » des individus. Les difficultés d'exploitation de telles rentes légitiment l'...

  13. Asie du sud | Page 7 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    L'éducation dans l'hémisphère sud est confrontée à plusieurs importants défis interdépendants dont la solution semble reposer sur les ressources éducatives libres (REL). Ces défis comprennent l'accès inégal à l'éducation, la qualité variable des ressources éducatives, de l'enseignement et du rendement des étudiants, ...

  14. Adoption and Impact of OER in the Global South | CRDI - Centre de ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    12 déc. 2017 ... L'éducation dans l'hémisphère sud est confrontée à plusieurs importants défis interdépendants dont la solution semble reposer sur les ressources éducatives libres (REL). Ces défis comprennent l'accès inégal à l'éducation, la qualité variable des ressources éducatives, de l'enseignement et du rendement ...

  15. Informationskompetence

    DEFF Research Database (Denmark)

    Schmidt, Maria Bøtker

    2014-01-01

    Det beskrives hvordan informationsøgningundervisning på læreruddannelsen på Fyn er tilrettelagt, for at sikre en sammenhæng mellem undervisning i bibliotekets ressourcer og den øvrige faglige undervisning. Teoretisk inddrages Illeris læringstrekant samt Kolb læringscirkel.......Det beskrives hvordan informationsøgningundervisning på læreruddannelsen på Fyn er tilrettelagt, for at sikre en sammenhæng mellem undervisning i bibliotekets ressourcer og den øvrige faglige undervisning. Teoretisk inddrages Illeris læringstrekant samt Kolb læringscirkel....

  16. Adoption and Impact of OER in the Global South | IDRC ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    12 déc. 2017 ... L'éducation dans l'hémisphère sud est confrontée à plusieurs importants défis interdépendants dont la solution semble reposer sur les ressources éducatives libres (REL). Ces défis comprennent l'accès inégal à l'éducation, la qualité variable des ressources éducatives, de l'enseignement et du rendement ...

  17. Successfull example for a sustainable architectural culture. Facade consisting of recycled wood wraps the administration building; Gelungenes Beispiel fuer nachhaltige Baukultur. Fassade aus Recycling-Holz umhuellt Verwaltungsbau

    Energy Technology Data Exchange (ETDEWEB)

    Blauel, Christian [BDA Mecklenburg-Vorpommern, Schwerin (Germany)

    2012-07-01

    It has a role-model status for sustainable and ecologic construction - the new headquarters for the Agency for Renewable Ressources (Guelzow, Federal Republic of Germany). The building mainly consists of renewable resources. The Agency for Renewable Ressources as a project bearer of the Federal Ministry of Food, Agriculture and Consumer Protection (Berlin, Federal Republic of Germany) and the state of Mecklenburg-Western Pomerania as a client in the public works have implemented all that of innovation and efficient use of energy and resources, for which private developers now stand more likely. The highlight is a facade fully realized by recycled oak wood.

  18. La réutilisation des eaux usées traitées en agriculture dans la délégation de Mornèg, en Tunisie

    OpenAIRE

    Selmi , Salah; Elloum , Mohamed; Hammami , Mohamed

    2005-01-01

    International audience; La rareté de l'eau en Tunisie justifie tout investissement supplémentaire pour la mobilisation et la mise à la disposition de l'eau dans les différents secteurs économiques, selon sa qualité et son usage potentiel. La réutilisation des eaux usées, après leur traitement, entre dans le cadre de la stratégie de mobilisation et de développement des ressources en eau du pays. En irrigation et par rapport aux ressources conventionnelles, la contribution des eaux usées traité...

  19. 12. Consommations alimentaires liées à la mondialisation

    OpenAIRE

    Russel, Marie; Esnouf, Catherine

    2017-01-01

    Pour qu’une alimentation soit durable, elle doit protéger la biodiversité et les écosystèmes, être acceptable culturellement, accessible économiquement, loyale, sûre, bonne pour la santé, et optimiser l’usage des ressources naturelles et humaines. La durabilité de l’alimentation est mise à l’épreuve face à un environnement de plus en plus incertain : croissance démographique, urbanisation, changement climatique, raréfaction et qualité des ressources naturelles, augmentation du prix du carbone...

  20. COMPARAISON ENERGETIQUE ET EXERGETIQUE DE SYSTEMES DE DESSALEMENT

    OpenAIRE

    Byrne , Paul; Diaby , Ahmadou ,; Sarray , Yemna; Ghoubali , Redouane; Loulergue , Patrick; Balannec , Béatrice; Maré , Thierry; Sow , Ousmane

    2016-01-01

    International audience; Dans certaines zones du monde, l'eau potable n'est pas une ressource abondante et est produite par des systèmes de dessalement. Par ailleurs, les ressources en énergie doivent être rationalisées. Les performances des systèmes de dessalement sont difficiles à comparer car les technologies peuvent être très différentes et faire appel à des procédés thermiques, électriques ou mécaniques, membranaires ou non. L'exergie correspond à l'énergie mécanique potentiellement produ...