WorldWideScience

Sample records for les experimentations nucleaires

  1. Associative memories in nuclear physics; Les memoires associatives en physique nucleaire

    Energy Technology Data Exchange (ETDEWEB)

    Blanca, E; Carriere, A [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1967-07-01

    Experiments in nuclear physics involve the use of large size 'memories'. After showing the difficulties arising from the use of such memories, the authors give the principles of the various programming methods which make it possible to operate the memories associatively thus benefiting from a reduction in size and better operational conditions. They attempt to estimate the shape and dimensions of an associative memory with cable connections which could be designed specially for nuclear research, contrary to those actually in service. (authors) [French] Les experiences de physique nucleaire necessitent l'emploi de 'memoires' de grandes dimensions. Apres avoir montre les inconvenients que presente l'utilisation de telles memoires, les auteurs exposent les principes des diverses methodes de programmation qui permettent d'assurer un fonctionnement des memoires sur le mode associatif donc une reduction de leurs dimensions et un meilleur usage. Ils tentent d'evaluer le format d'une memoire associative cablee qui, contrairement a celles qui existent actuellement, serait prevue specialement pour l'experimentation nucleaire. (auteurs)

  2. Experimental study of the hydrodynamic instabilities occurring in boiling-water reactors; Etude experimentale des instabilites hydrodynamiques survenant dans les reacteurs nucleaires a ebullition

    Energy Technology Data Exchange (ETDEWEB)

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

    1964-10-01

    The subjects is an experimental out-of pile loop study of the hydrodynamic oscillations occurring in boiling-water reactors. The study was carried out at atmospheric pressure and at pressure of about 8 atmospheres, in channels heated electrically by a constant and uniform specified current. In the test at 8 atmospheres the channel was a round tube of approximately 6 mm interior diameter. At 1 atmosphere a ring-section channel was used, 10 * 20 mm in diameter, with an inner heating tube and an outer tube of pyrex. It was possible to operate with natural convection and also with forced convection with test-channel by-pass. The study consists of 3 parts: 1. Preliminary determination of the laws governing pressure-drop during boiling. 2. Determination of the fronts at which oscillation appears, within a wide range of the parameters involved. 3. A descriptive study of the oscillations and measurement of the periods. The report gives the oscillation fronts with natural and forced convection for various values of the singular pressure drop at the channel inlet and for various riser lengths. The results are presented in non-dimensional form, which is available, in first approximation, for all geometric scales and for all fluids. Besides the following points were observed: - the wall (nature and thickness) can be an important factor ; - oscillation can occur in a horizontal channel. (author) [French] II a ete effectue une etude experimentale, en boucle hors-pile, des oscillations hydrodynamiques survenant dans les reacteurs a ebullition. L'etude a ete effectuee a la pression atmospherique et a une pression voisine de 8 atmospheres dans des canaux chauffes electriquement a puissance imposee constante et uniforme. Dans les essais a 8 atmospheres le canal etait un tube circulaire de diametre interieur 6 mm environ. A 1 atmosphere le canal etait de section annulaire 10 * 20 mm avec un tube interieur chauffant et un tube exterieur en pyrex. Le fonctionnement etait possible

  3. Experimental study of the hydrodynamic instabilities occurring in boiling-water reactors; Etude experimentale des instabilites hydrodynamiques survenant dans les reacteurs nucleaires a ebullition

    Energy Technology Data Exchange (ETDEWEB)

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

    1964-10-01

    The subjects is an experimental out-of pile loop study of the hydrodynamic oscillations occurring in boiling-water reactors. The study was carried out at atmospheric pressure and at pressure of about 8 atmospheres, in channels heated electrically by a constant and uniform specified current. In the test at 8 atmospheres the channel was a round tube of approximately 6 mm interior diameter. At 1 atmosphere a ring-section channel was used, 10 * 20 mm in diameter, with an inner heating tube and an outer tube of pyrex. It was possible to operate with natural convection and also with forced convection with test-channel by-pass. The study consists of 3 parts: 1. Preliminary determination of the laws governing pressure-drop during boiling. 2. Determination of the fronts at which oscillation appears, within a wide range of the parameters involved. 3. A descriptive study of the oscillations and measurement of the periods. The report gives the oscillation fronts with natural and forced convection for various values of the singular pressure drop at the channel inlet and for various riser lengths. The results are presented in non-dimensional form, which is available, in first approximation, for all geometric scales and for all fluids. Besides the following points were observed: - the wall (nature and thickness) can be an important factor ; - oscillation can occur in a horizontal channel. (author) [French] II a ete effectue une etude experimentale, en boucle hors-pile, des oscillations hydrodynamiques survenant dans les reacteurs a ebullition. L'etude a ete effectuee a la pression atmospherique et a une pression voisine de 8 atmospheres dans des canaux chauffes electriquement a puissance imposee constante et uniforme. Dans les essais a 8 atmospheres le canal etait un tube circulaire de diametre interieur 6 mm environ. A 1 atmosphere le canal etait de section annulaire 10 * 20 mm avec un tube interieur chauffant et un tube exterieur en pyrex. Le fonctionnement etait possible en

  4. Molten salts in nuclear reactors; Les sels fondus dans les reacteurs nucleaires

    Energy Technology Data Exchange (ETDEWEB)

    Dirian, J; Saint-James, [Commissariat a l' Energie Atomique, Saclay (France).Centre d' Etudes Nucleaires

    1959-07-01

    Collection of references dealing with the physicochemical studies of fused salts, in particular the alkali and alkali earth halides. Numerous binary, ternary and quaternary systems of these halides with those of uranium and thorium are examined, and the physical properties, density, viscosity, vapour pressure etc... going from the halides to the mixtures are also considered. References relating to the corrosion of materials by these salts are included and the treatment of the salts with a view to recuperation after irradiation in a nuclear reactor is discussed. (author) [French] Bibliographie regroupant l'etude physico-chimique des sels fondus, en particulier des halogenures alcalins et alcalino-terreux. On etudie de nombreux systemes binaires, ternaires et quaternaires de ces halogenures avec des halogenures d'uranium, et de thorium. On etudie egalement les proprietes physiques des halogenures ou des melanges d'halogenures (densite, viscosite, tension de vapeur, etc...). On donne egalement des references quant a la corrosion des materiaux par ces sels, et le traitement de ceux-ci en vue de recuperation, apres irradiation dans un reacteur nucleaire. (auteur)

  5. Nuclear biological studies in France; Les etudes de biologie nucleaires en France

    Energy Technology Data Exchange (ETDEWEB)

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

    1961-07-01

    On the occasion of a colloquium on radiobiological research programmes, a number of documents dealing with French accomplishments and projects in this field were collected together. We felt that it would be useful to assemble these papers in one report; although they are brief and leave gaps to be filled in, they provide certain data, give an overall view of the situation, and can also suggest a rough plan for the general policy to adopt in the field of 'nuclear' biological research; i.e. research based on the nuclear tracer method or devoted to the action of ionising radiations. (author) [French] Un colloque sur les programmes de recherche en radiobiologie nous a donne l'occasion de reunir des documents sur les realisations et les projets francais dans ce domaine. Il nous a semble utile de reunir en un rapport l'ensemble de ces documents, qui, malgre leur brievete et malgre les lacunes qu'ils comportent, donnent un certain nombre d'informations, permettent une vue d'ensemble et peuvent dessiner aussi l'ebauche d'une politique coherente en matiere de recherches biologiques 'nucleaires', c'est-a-dire de recherches basees sur la methode des indicateurs nucleaires ou consacrees a l'action des rayonnements ionisants. (auteur)

  6. Nuclear biological studies in France; Les etudes de biologie nucleaires en France

    Energy Technology Data Exchange (ETDEWEB)

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

    1961-07-01

    On the occasion of a colloquium on radiobiological research programmes, a number of documents dealing with French accomplishments and projects in this field were collected together. We felt that it would be useful to assemble these papers in one report; although they are brief and leave gaps to be filled in, they provide certain data, give an overall view of the situation, and can also suggest a rough plan for the general policy to adopt in the field of 'nuclear' biological research; i.e. research based on the nuclear tracer method or devoted to the action of ionising radiations. (author) [French] Un colloque sur les programmes de recherche en radiobiologie nous a donne l'occasion de reunir des documents sur les realisations et les projets francais dans ce domaine. Il nous a semble utile de reunir en un rapport l'ensemble de ces documents, qui, malgre leur brievete et malgre les lacunes qu'ils comportent, donnent un certain nombre d'informations, permettent une vue d'ensemble et peuvent dessiner aussi l'ebauche d'une politique coherente en matiere de recherches biologiques 'nucleaires', c'est-a-dire de recherches basees sur la methode des indicateurs nucleaires ou consacrees a l'action des rayonnements ionisants. (auteur)

  7. Direct interaction in nuclear reactions: a theory; L'interaction directe dans les reactions nucleaires: theorie

    Energy Technology Data Exchange (ETDEWEB)

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

    1959-07-01

    General treatment of the foundations of direct interaction in nuclear reactions; representation of the instantaneous elastic scattering amplitude by the scattering amplitude due to a complex potential; expansion of the instantaneous inelastic scattering amplitude and discussion of the 1. Bohr approximation (distorted waves) contribution to individual and collective states of excitation. (author) [French] Expose general sur les fondements de l'interaction directe dans les reactions nucleaires; representation de l'amplitude de diffusion instantanee elastique par celle due a un potentiel complexe; developpement de l'amplitude de diffusion instantanee inelastique et discussion de la contribution de la premiere approximation de Bohr (sur des distendues) a l'excitation d'etats individuels et collectifs. (auteur)

  8. French research in the field of nuclear agronomy; Les recherches francaises en agronomie nucleaire

    Energy Technology Data Exchange (ETDEWEB)

    Guerin De Montgareuil, P. [Commissariat a l' Energie Atomique, Cadarache (France). Centre d' Etudes Nucleaires

    1964-07-01

    , industrial firms, university laboratories scientific institutes. The role of the Commissariat a l'Energie Atomique is defined: on the one hand it supplies information and support, and on the other hand it takes charge of specifically nuclear aspects of the work. Its part in the field has recently found expression in the creation, within the Biology Department, of a Radio-agronomy Section; its objective are described,, as well as the, means placed att its disposal at the Centre d'etudes Nucleaires, Cadarache. (author) [French] On propose un bilan des travaux les plus significatifs effectues en France depuis la deuxieme conference internationale en matiere d'agronomie nucleaire et qui vont d'une recherche apparemment desinteressee a l'application la plus directe. Une telle differenciation recouvre de moins en moins, au fur et a mesure de l'evolution des programmes, la distinction qui est faite dans l'expose entre l'action biologique des rayonnements et les autres emplois des techniques nucleaires. C'est ainsi que les recherches do radiogenetique agricole sont poursuivies dans deux directions: d'un point de vue theorique et methodologique avec l'etude comparative de l'action des divers types de rayonnements, l'influence du debit de dose et de la temperature, l'action des agents mutagenes chimiques, la production de chimeres sous irradiation gamma; et d'autre part, sous un aspect pratique aboutissant a la creation de varietes nouvelles plus resistantes ou plus precoces (riz, mil, arachide). Les problemes de destruction des insectes (eradication) et de conservation des denrees sous irradiation se trouvent egalement abordes par des voies et avec des objectifs tres divers. A la demarche globale representee par une irradiation pure et simple (grains humides, pommes de terre...) sont parfois associees des etudes souvent originales, d'ordre biochimique ou microbiologique (par exemple: alteration de l

  9. French research in the field of nuclear agronomy; Les recherches francaises en agronomie nucleaire

    Energy Technology Data Exchange (ETDEWEB)

    Guerin De Montgareuil, P [Commissariat a l' Energie Atomique, Cadarache (France). Centre d' Etudes Nucleaires

    1964-07-01

    , industrial firms, university laboratories scientific institutes. The role of the Commissariat a l'Energie Atomique is defined: on the one hand it supplies information and support, and on the other hand it takes charge of specifically nuclear aspects of the work. Its part in the field has recently found expression in the creation, within the Biology Department, of a Radio-agronomy Section; its objective are described,, as well as the, means placed att its disposal at the Centre d'etudes Nucleaires, Cadarache. (author) [French] On propose un bilan des travaux les plus significatifs effectues en France depuis la deuxieme conference internationale en matiere d'agronomie nucleaire et qui vont d'une recherche apparemment desinteressee a l'application la plus directe. Une telle differenciation recouvre de moins en moins, au fur et a mesure de l'evolution des programmes, la distinction qui est faite dans l'expose entre l'action biologique des rayonnements et les autres emplois des techniques nucleaires. C'est ainsi que les recherches do radiogenetique agricole sont poursuivies dans deux directions: d'un point de vue theorique et methodologique avec l'etude comparative de l'action des divers types de rayonnements, l'influence du debit de dose et de la temperature, l'action des agents mutagenes chimiques, la production de chimeres sous irradiation gamma; et d'autre part, sous un aspect pratique aboutissant a la creation de varietes nouvelles plus resistantes ou plus precoces (riz, mil, arachide). Les problemes de destruction des insectes (eradication) et de conservation des denrees sous irradiation se trouvent egalement abordes par des voies et avec des objectifs tres divers. A la demarche globale representee par une irradiation pure et simple (grains humides, pommes de terre...) sont parfois associees des etudes souvent originales, d'ordre biochimique ou microbiologique (par exemple: alteration de l'amidon, metabolisme glucidique des tubercules irradies, radioresistance des levures

  10. Corrosion by cooling gases in nuclear reactors; la corrosion par les gaz caloporteurs dans les reacteurs nucleaires

    Energy Technology Data Exchange (ETDEWEB)

    Darras, R. [Commissariat a l' energie atomique et aux energies alternatives - CEA, Centre de Saclay, Section d' etude de la corrosion par gaz et metaux liquides (France)

    1960-07-01

    This article begins with a review of the various materials which can be used and the cooling gases in which they may be heated, emphasis being placed on the importance of reaching temperatures as high as possible. This is followed by a few general remarks on the dry oxidation of metals and alloys, particularly with regard to diffusion phenomena and their various possible mechanisms, and also the methods of investigation employed. Finally, the behaviour of the chief nuclear materials heated in the various gases is studied successively. Materials used for fuel (metallic uranium, uranium oxide, carbides and silicides), canning materials (magnesium, aluminium, zirconium, beryllium, stainless and refractory steels), structural materials (ordinary or slightly alloyed steels), and finally moderators (graphite, beryllium oxide) are deal with in this way. This account is backed up both by the results obtained at the CEA and by work published outside or abroad up to the present day. In conclusion, every effort has been made to direct future research on the basis of the foregoing. Reprint of a paper published in Industries Atomiques - no. 9/10, 1959, p. 3-23 [French] Dans cet article, on passe tout d'abord en revue les divers materiaux utilisables et les gaz de refroidissement dans lesquels ils peuvent etre chauffes, en insistant sur l'interet d'atteindre des temperatures aussi elevees que possible. On rappelle ensuite quelques generalites sur l'oxydation seche des metaux et alliages, notamment en ce qui concerne les phenomenes de diffusion et leurs divers mecanismes possibles ainsi que les methodes d'etude. Enfin, le comportement des principaux materiaux nucleaires chauffes dans les divers gaz est etudie successivement. On traita ainsi des materiaux combustibles (uranium metallique, oxyde, carbures et siliciures d'uranium), des materiaux de gainage (magnesium, aluminium, zirconium, beryllium, aciers inoxydables et refractaires), des materiaux de structure (aciers ordinaires

  11. The dangers of irradiate uranium in nuclear reactors; Les dangers de l'uranium irradie dans les reacteurs nucleaires

    Energy Technology Data Exchange (ETDEWEB)

    Jammet, H; Joffre, H [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1955-07-01

    The danger of the uranium cans sur-activated by the use in the nuclear reactors is triple: - Irradiation from afar, during manipulations of the cans. - Contamination of air when decladding. - Contamination of air by fire of uranium in a reactor in function The first two dangers are usual and can be treated thanks to the rules of security in use in the atomic industry. The third has an accidental character and claimed for the use of special and exceptional rules, overflowing the industrial setting, to reach the surrounding populations. (authors) [French] Le danger des cartouches d'uranium suractive par utilisation dans les reacteurs nucleaires est triple: - Irradiation a distance, lors des manipulations des cartouches. - Contamination de l'air au moment de leur degainage. - Contamination de l'air par incendie d'uranium dans un reacteur en fonctionnement. Les deux premiers dangers sont habituels et peuvent etre traites grace aux regles de securite en usage dans l'industrie atomique. Le troisieme revet un caractere accidentel et reclame l'emploi de regles speciales et exceptionnelles, debordant le cadre industriel, pour atteindre celui des populations environnantes. (auteurs)

  12. Health problems raised by the elimination of radioactive wastes and nuclear accidents; Problemes sanitaires poses par l'elimination des dechets radioactifs et par les accidents nucleaires

    Energy Technology Data Exchange (ETDEWEB)

    Jammet, H; Mechali, D; Dousset, M [Commissariat a l' Energie Atomique, Fontenay-aux-Roses (France). Centre d' Etudes Nucleaires

    1964-07-01

    The rapid development of nuclear energy demands an urgent solution to the health problems arising from the discharge into the environment of radioactive residues produced by nuclear installations. - To be able to evaluate the risks run by the population and to fix tolerance limits for waste discharge, it is necessary to possess an exact knowledge of the course taken by the radioelements discharged, from their source until they reach man. The incorporation of radioelements in food cycles is the first risk to take into consideration. The factors involved in all stages of this transmission must be foreseen, whether they concern physical or biological media, because of their continuity and their interdependence. Finally, socio-economic and dietetic data must be collected in order that the risks and tolerance levels estimated are based on concrete and experimental rather than theoretical knowledge. The risk of nuclear accidents in the atomic industry, although very improbable, must be taken into consideration because of the seriousness of their consequences. The health problems arise in the field of professional hygiene on the one hand and in that of public hygiene on the other. In the first field the risk is two-fold and involves irradiation and contamination. The public sphere is reduced essentially to the risk of contamination by radioactive substances accidentally released in the surrounding medium. The health studies to be conducted in this field therefore include research not only on irradiation or contamination therapeutics but also on the transfer of radioelements from the accident site to man, mainly through food cycles, in their physical and in their biological components. Studies of this kind form the basis of decisions in the health field which would have to be taken in the case of an accident. (authors) [French] Le developpement rapide de l'energie nucleaire rend urgente la solution des problemes sanitaires poses par le rejet dans le milieu ambiant des

  13. Contribution to the study of nuclear resonance in magnetic media (1963); Contribution a l'etude de la resonance nucleaire dans les milieux magnetique (1963)

    Energy Technology Data Exchange (ETDEWEB)

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

    1963-06-15

    An attempt is made to interpret the results of nuclear magnetic resonance experiments made by various workers on ferro and ferrimagnetic compounds of the iron group. The problems encountered are the following: effects of the dipolar fields and the hyperfine structure anisotropy; signal intensity; frequency pulling due to the Suhl-Nakamura interaction between nuclear spins ; nuclear relaxation and ferrimagnetic resonance in single domain samples of impure YIG; nuclear relaxation in the Bloch walls of insulators. The results of our calculations are generally in good agreement with experiment. (author) [French] On se propose d'interpreter les resultats d'experiences de resonance magnetique nucleaire fates par divers auteurs sur des composes ferro et ferrimagnetiques du groupe du fer. Les problemes abordes sont les suivants: effets des champs dipolaires et de l'anisotropie de structure hyperfine; intensite des signaux; deplacement de frequence du a l'interaction de Suhl-Nakamura entre spins nucleaires; relaxation nucleaire et resonance ferrimagnetique dans les echantillons monodomaines de grenat de fer et d'yttrium impur; relaxation nucleaire dans les parois de Bloch des isolants. Les resultats des calculs sont generalement en bon accord avec l'experience. (auteur)

  14. Contribution to the study of nuclear resonance in magnetic media (1963); Contribution a l'etude de la resonance nucleaire dans les milieux magnetique (1963)

    Energy Technology Data Exchange (ETDEWEB)

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

    1963-06-15

    An attempt is made to interpret the results of nuclear magnetic resonance experiments made by various workers on ferro and ferrimagnetic compounds of the iron group. The problems encountered are the following: effects of the dipolar fields and the hyperfine structure anisotropy; signal intensity; frequency pulling due to the Suhl-Nakamura interaction between nuclear spins ; nuclear relaxation and ferrimagnetic resonance in single domain samples of impure YIG; nuclear relaxation in the Bloch walls of insulators. The results of our calculations are generally in good agreement with experiment. (author) [French] On se propose d'interpreter les resultats d'experiences de resonance magnetique nucleaire fates par divers auteurs sur des composes ferro et ferrimagnetiques du groupe du fer. Les problemes abordes sont les suivants: effets des champs dipolaires et de l'anisotropie de structure hyperfine; intensite des signaux; deplacement de frequence du a l'interaction de Suhl-Nakamura entre spins nucleaires; relaxation nucleaire et resonance ferrimagnetique dans les echantillons monodomaines de grenat de fer et d'yttrium impur; relaxation nucleaire dans les parois de Bloch des isolants. Les resultats des calculs sont generalement en bon accord avec l'experience. (auteur)

  15. The experimental nuclear reactor: AQUILON; Le reacteur nucleaire experimental: AQUILON

    Energy Technology Data Exchange (ETDEWEB)

    Girard, Y; Koechlin, J C; Moreau, J M [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1958-07-01

    'Aquilon' is an experimental reactor specially designed for the neutronic study of heterogeneous multiplying media with solid fuel and liquid moderator. Since this study is in general incompatible with energy production, the power of the reactor has been limited to a minimum so as to be able to obtain a simple and compact structure, easy access, good handling and great flexibility of operation and utilisation. (author) [French] 'Aquilon' est un reacteur experimental specialement concu pour l'etude neutronique de milieux multiplicateurs heterogenes a combustible solide et ralentisseur liquide. Cette etude etant en general incompatible avec la production d'energie, on a limite au minimum la puissance du reacteur pour pouvoir obtenir une structure simple et peu encombrante, un acces facile, une bonne maniabilite et une grande souplesse de fonctionnement et d'utilisation. (auteur)

  16. Health problems raised by the elimination of radioactive wastes and nuclear accidents; Problemes sanitaires poses par l'elimination des dechets radioactifs et par les accidents nucleaires

    Energy Technology Data Exchange (ETDEWEB)

    Jammet, H.; Mechali, D.; Dousset, M. [Commissariat a l' Energie Atomique, Fontenay-aux-Roses (France). Centre d' Etudes Nucleaires

    1964-07-01

    The rapid development of nuclear energy demands an urgent solution to the health problems arising from the discharge into the environment of radioactive residues produced by nuclear installations. - To be able to evaluate the risks run by the population and to fix tolerance limits for waste discharge, it is necessary to possess an exact knowledge of the course taken by the radioelements discharged, from their source until they reach man. The incorporation of radioelements in food cycles is the first risk to take into consideration. The factors involved in all stages of this transmission must be foreseen, whether they concern physical or biological media, because of their continuity and their interdependence. Finally, socio-economic and dietetic data must be collected in order that the risks and tolerance levels estimated are based on concrete and experimental rather than theoretical knowledge. The risk of nuclear accidents in the atomic industry, although very improbable, must be taken into consideration because of the seriousness of their consequences. The health problems arise in the field of professional hygiene on the one hand and in that of public hygiene on the other. In the first field the risk is two-fold and involves irradiation and contamination. The public sphere is reduced essentially to the risk of contamination by radioactive substances accidentally released in the surrounding medium. The health studies to be conducted in this field therefore include research not only on irradiation or contamination therapeutics but also on the transfer of radioelements from the accident site to man, mainly through food cycles, in their physical and in their biological components. Studies of this kind form the basis of decisions in the health field which would have to be taken in the case of an accident. (authors) [French] Le developpement rapide de l'energie nucleaire rend urgente la solution des problemes sanitaires poses par le rejet dans le milieu ambiant des

  17. Damage caused to houses and equipment by underground nuclear explosions; Degats dus aux explosions nucleaires souterraines sur les habitations et les equipements

    Energy Technology Data Exchange (ETDEWEB)

    Delort, F; Guerrini, C [Commissariat a l' Energie Atomique, Bruyeres-le-Chatel (France). Centre d' Etudes

    1969-07-01

    A description is given of the damaged caused to various structures, buildings, houses, mechanical equipment and electrical equipment by underground nuclear explosions in granite. For each type of equipment or building are given the limiting distances for a given degree of damage. These distances have been related to a parameter characterizing the movement of the medium; it is thus possible to generalize the results obtained in granite, for different media. The problem of estimating the damage caused at a greater distance from the explosion is considered. (authors) [French] Les degats sur diverses structures, constructions, habitations, equipements mecaniques et materiels electriques provoques par des explosions nucleaires souterraines dans le granite sont decrits. On a indique pour chaque type de materiel ou de construction, les distances limites correspondant a un degre de gravite de dommage observe. Ces distances ont ete reliees a un parametre caracterisant le mouvement du milieu, permettant ainsi de generaliser les resultats obtenus dans le granite, a differents milieux. Le probleme de la prevision des degats en zone lointaine a ete aborde. (auteurs)

  18. The nuclear power stations of the French atomic energy programme (1960); Les centrales nucleaires de puissance du programme francais (1960)

    Energy Technology Data Exchange (ETDEWEB)

    Leduc, C [Commissariat a l' Energie Atomique, Saclay (France).Centre d' Etudes Nucleaires; Roux, J P [Electricite de France (EDF), 75 - Paris (France)

    1960-07-01

    After recalling the entry of nuclear energy into energy production in France, the paper emphasizes the evolution of techniques applied in the designing of French nuclear power plants and describes the means employed for reducing costs per kWh of EDF2 and EDF3 compared with EDF1: the electric power per ton of uranium varies from 493 kW/t for EDF1 to 970 kW/t for EDF3. For this purpose the thermal power and electric power of units are changed respectively from 290 MWt for EDF1 to 1200 or 1600 MWt for EDF3 and from 28 to 250 MW. The results are obtained by an improvement in neutronic characteristics, developments in nuclear fuel technology, and simplification of the system of charging the reactor, whose means of maintenance are increased; the EDF2 heat-exchangers have been so designed as to increase the unit power of the elements, which will attain 9 MWt, as against 3 for EDF1. For EDF3 an advance project forecasts a thermodynamic layout with only one pressure stage. The paper ends with a description of the burst-slug detection systems, and an appendix gives a detailed comparative table of EDF1, EDF2 and EDF3 plant characteristics. (author) [French] Apres avoir rappele l'integration de l'energie nucleaire parmi les moyens de production de l'energie en France, les auteurs se penchent surtout sur l'evolution des techniques appliquees dans l'equipement des centrales nucleaires francaises et decrivent les moyens mis en oeuvre pour reduire les prix de revient du kWh d'EDF2 et d'EDF3 par rapport a EDF1: la puissance electrique par tonne d'uranium varie de 493 kW/t pour EDF1 a 970 kW/t pour EDF3. C'est dans ce but que les puissances thermiques et la puissance unitaire des groupes turbo-alternateurs passent respectivement de 290 MWt pour EDF1 a 1200 ou 1600 MWt pour EDF3 et de 82 a 250 MW. Les resultats sont obtenus par une amelioration des caracteristiques neutroniques, des progres realises sur la technologie des elements combustibles, une simplification du systeme de

  19. Plutonium, nuclear fuel; Le plutonium, combustible nucleaire

    Energy Technology Data Exchange (ETDEWEB)

    Grison, E [Commissariat a l' Energie Atomique, Fontenay aux Roses (France). Centre d' Etudes Nucleaires, Saclay

    1960-07-01

    A review of the physical properties of metallic plutonium, its preparation, and the alloys which it forms with the main nuclear metals. Appreciation of its future as a nuclear fuel. (author) [French] Apercu sur les proprietes physiques du plutonium metallique, sa preparation, ses alliages avec les principaux metaux nucleaires. Consideration sur son avenir en tant que combustible nucleaire. (auteur)

  20. Description of methods for making activation detectors for use in nuclear reactors; Description des procedes de fabrication des detecteurs d'activation utilises dans les reacteurs nucleaires

    Energy Technology Data Exchange (ETDEWEB)

    Barbalat, R; Le Coguie, R; Leger, P; Salon, L; Thierry, M [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1968-07-01

    A brief description of methods currently used for making activation detectors, thin films and various deposits used in nuclear reactors. The thicknesses required vary from about a few tenths of a micron to a few tenths of a millimeter. Different techniques are used for fixing the large variety of elements: rolling, moulding, painting, electrolysis, vacuum deposition, thin films, wires, enamels, protective linings, etc. (authors) [French] Expose succinct des procedes actuellement mis en oeuvre pour la realisation des detecteurs d'activation, feuilles minces et depots divers utilises dans les reacteurs nucleaires. La gamme des epaisseurs necessaires s'etendant approximativement des dixiemes de micrometre aux dixiemes de millimetre. La diversite des elements a fixer justifiant les techniques differentes selon les cas: laminage, moulage, peinture, electrolyse, depot sous vide, couches minces, fils, emaux, revetements protecteurs, etc. (auteurs)

  1. Possibilities and limitations of analogue methods for studying the dynamics of nuclear power stations; Possibilites et limitations du calcul analogique pour les etudes dynamiques de centrales nucleaires

    Energy Technology Data Exchange (ETDEWEB)

    Caillet, C; Deat, M [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1958-07-01

    1. Introduction: the present paper is devoted to analog simulation of problems related to nuclear reactors other than the simulation of the kinetic equations which is well known. 2. Thermodynamic problems: various problems relative to temperature evolution in a reactor, in a pipe, in an exchanger, in a turbine, are studied, and simulation techniques used by earlier authors are critically reviewed. 3. Pipe simulators: it is shown that this problem can be solved by the use of specialized simulators which will be described and analysed. 4. Rotating machine simulators: the particular aspect of rotating machine calculations introducing frequent use of diagrams is emphasized. A simulator requiring both digital and analogue methods is described. 5. The study of a nuclear power station: as an example it is proposed to discuss problems a rising in connection with the preceding elements (a, b, c, d) when simulating the behaviour of large nuclear plants. The part played by ordinary computing elements for the simulation of the different servomechanism transfer functions is considered and process of regulation is outlined. 6. Conclusion: the necessity of the use of high quality simulators and computers is underlined and the accuracy of the solutions is discussed. (author)Fren. [French] 1. Cinetique des reacteurs: la simulation des equations cinetiques d'un reacteur nucleaire ne pose desormais plus de probleme. II est donc possible de faire le point des differentes applications de la technique analogique dans ce domaine. 2. Les problemes thermodynamiques: on discute les differents problemes poses par l'evolution des temperatures dans un reacteur, dans une tuyauterie, dans un echangeur, dans une turbine, et on passe en revue les techniques de simulation proposees jusqu'a ce jour. 3s simulateurs de tuyauteries: on montre comment les differents problemes poses ci-dessus peuvent etre resolus, pour une classe tres vaste de reacteurs par l'emploi de simulateurs speciaux que l

  2. Some fundamental aspects of boiling in nuclear reactors; Quelques aspects fondamentaux de l'ebullition dans les reacteurs nucleaires

    Energy Technology Data Exchange (ETDEWEB)

    Mondin, H; Lavigne, P; Semeria, R [Commissariat a l' Energie Atomique, Grenoble (France). Centre d' Etudes Nucleaires

    1964-07-01

    oscillation, the conditions of burnout are compared with those obtained under steady conditions. The burn-out flux following uniform 'stopped' heating has been studied in a channel containing still water. The flux shows a maximum as a function of unsaturation. The influence of the geometry and the nature of the metal was investigated. 4 - Output Oscillations: Using a low pressure (8 atm) loop, the influence of various parameters on the periods of output oscillations in a boiling channel on the thresholds at which they appear, was studied. Some new aspects of this complex phenomena were observed and are reported. (authors) [French] On indique les principaux resultats obtenus a Grenoble depuis quatre ans dans le domaine des mecanismes de l'ebullition et des phenomenes connexes dans les reacteurs nucleaires. 1 - OBSERVATION DE L'EBULLITION: Par photographie et cinematographie ultrarapide (8000 images par seconde maximum) on a observe l'ebullition en vase ou en canal jusqu'a 140 kg/cm{sup 2}. On a denombre les populations de germes (sites) generateurs de bulles et obtenu une correlation donnant leur nombre par unite de surface en fonction du flux thermique et de la pression. Le diametre des bulles se detachant de la paroi a ete etudie jusqu'a 140 kg/cm{sup 2}. On a mis en evidence trois types de bulles: - Les bulles en equilibre dont le diametre suit la formule de Fritz et Ende, - Les bulles d'ebullition dont le diametre diminue rapidement avec la pression (1/100 mm a 140 kg/cm{sup 2}), - Les coalescences apparaissant en liquide sature au-dessus de 15 W/cm{sup 2} et dont la proportion est independante de la pression. Par visualisation en strioscopie on observe les mouvements du film thermique associes a l'amorcage des germes, au depart et a la condensation des bulles; les mecanismes responsables de l'excellent transfert de chaleur ont pu ainsi etre precises. 2 - PERTES DE PRESSION EN ECOULEMENT DIPHASE: On a etabli un modele de variation continue du taux de vide dans un canal

  3. Contribution to the Study of Nuclear Magnetic Resonance in Ferromagnets; Contribution a l'etude de la resonance nucleaire dans les corps ferromagnetiques

    Energy Technology Data Exchange (ETDEWEB)

    Robert, C. [Commissariat a l' Energie Atomique, Centre d' Etudes Nucleaires de Saclay, 91 - Gif-sur-Yvette (France)

    1962-07-01

    Properties of nuclear magnetic resonance in the field acting on the nucleus in a ferromagnet were studied. Nuclei were {sup 57}Fe in iron and yttrium iron garnet. Static properties of resonance (frequency, line-width, dipolar structure) were investigated and compared with magnetic behavior and magnetic structure of the materials. Relaxation in garnet points out importance of long range fluctuations induced by impurities in a ferromagnetic lattice. (author) [French] Nous avons etudie les proprietes de la resonance nucleaire dans le champ existant a remplacement d'un noyau dans un corps ferromagnetique (champ local). Les noyaux etaient ceux de {sup 57}Fe dans le fer et dans le grenat d'yttrium et de fer. Les proprietes statiques de la resonance (frequence de resonance, largeur de la raie, structures dues a l'interaction dipolaire) ont ete etudiees et reliees aux caracteristiques magnetiques et a la structure de ces corps. La relaxation dans le grenat a mis en evidence les fluctuations a longue distance induites par des impuretes dans un reseau ferromagnetique. (auteur)

  4. Contribution to the Study of Nuclear Magnetic Resonance in Ferromagnets; Contribution a l'etude de la resonance nucleaire dans les corps ferromagnetiques

    Energy Technology Data Exchange (ETDEWEB)

    Robert, C [Commissariat a l' Energie Atomique, Centre d' Etudes Nucleaires de Saclay, 91 - Gif-sur-Yvette (France)

    1962-07-01

    Properties of nuclear magnetic resonance in the field acting on the nucleus in a ferromagnet were studied. Nuclei were {sup 57}Fe in iron and yttrium iron garnet. Static properties of resonance (frequency, line-width, dipolar structure) were investigated and compared with magnetic behavior and magnetic structure of the materials. Relaxation in garnet points out importance of long range fluctuations induced by impurities in a ferromagnetic lattice. (author) [French] Nous avons etudie les proprietes de la resonance nucleaire dans le champ existant a remplacement d'un noyau dans un corps ferromagnetique (champ local). Les noyaux etaient ceux de {sup 57}Fe dans le fer et dans le grenat d'yttrium et de fer. Les proprietes statiques de la resonance (frequence de resonance, largeur de la raie, structures dues a l'interaction dipolaire) ont ete etudiees et reliees aux caracteristiques magnetiques et a la structure de ces corps. La relaxation dans le grenat a mis en evidence les fluctuations a longue distance induites par des impuretes dans un reseau ferromagnetique. (auteur)

  5. Thermal energy of nuclear origin produced in non-fissile materials (1962); Energie calorifique d'origine nucleaire degagee dans les materiaux non fissiles (1962)

    Energy Technology Data Exchange (ETDEWEB)

    Naudet, G [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires; Millies, P; Berger, J [Commissariat a l' Energie Atomique, Grenoble (France). Centre d' Etudes Nucleaires

    1962-07-01

    A first part is devoted to the description of the interaction phenomena between elementary particles and material that may be observed during the irradiation process in a nuclear reactor: nuclear reactions due to neutrons, production of gamma rays and absorption of those gamma rays through various processes. In a second part the phenomena producing calorific energy in irradiated material are quantitatively examined. In the third part results are summed up in a formulary. The fourth part presents tables and figures giving to the reader all the numerical values necessary for practical calculations. (authors) [French] Une premiere partie est consacree a l'examen des principaux phenomenes d'interaction des particules avec la matiere qui interviennent lors d'une irradiation dans un reacteur: reactions nucleaires dues aux neutrons, production des rayons gamma et absorption de ces derniers par les divers processus. Une deuxieme partie etudie quantitativement les phenomenes qui conduisent a l'apparition d'energie calorifique dans le materiau irradie. En troisieme partie, un formulaire resume les resultats etablis. Dans une quatrieme partie, des tableaux et des courbes fournissent a l'experimentateur toutes les valeurs numeriques necessaires aux calculs pratiques. (auteurs)

  6. Material movement of medium surrounding an underground nuclear explosion; Mouvement materiel du milieu environnant une explosion nucleaire souterraine

    Energy Technology Data Exchange (ETDEWEB)

    Guerrini, C; Garnier, J L [Commissariat a l' Energie Atomique, Bruyeres-le-Chatel (France). Centre d' Etudes

    1969-07-01

    The results of measurements of the mechanical effects in the, intermediate zone around underground nuclear explosions in Sahara granite are presented. After a description of the main characteristics of the equipment used, the laws drawn up using experimental results for the acceleration, the velocity, and the material displacement are presented. These laws are compared to those published in other countries for nuclear tests in granite, in tuff and in alluvial deposits. (authors) [French] Les resultats de mesures d'effets mecaniques en zone intermediaire autour d'essais nucleaires souterrains dans le granite du Sahara sont exposes. Apres avoir decrit, dans leurs grandes lignes, les materiels utilises, on presente les lois etablies avec les resultats experimentaux pour l'acceleration, la vitesse et le deplacement materiel. Ces lois sont comparees a celles publiees a l'etranger pour des essais nucleaires dans le granite, le tuf et les alluvions. (auteur)

  7. Atomic Transport Problems of Interest in Nuclear Systems; Problemes de Transport Atomique Presentant un Interet dans les Systemes Nucleaires; Problemy perenosa atomov, predstavlyayushchie interes v yadernykh sistemakh; Problemas de Transporte Atomico de Interes para la Ingenieria Nuclear

    Energy Technology Data Exchange (ETDEWEB)

    Lundy, T. S.; Winslow, F. R. [Oak Ridge National Laboratory, TN (United States)

    1966-02-15

    ) [French] Les auteurs discutent plusieurs problemes qui surgissent lorsqu'on veut appliquer les constantes fondamentales de diffusion a des systemes presentant un interet pratique, notamment a ceux que l'on rencontre dans le genie nucleaire. Ces problemes comprennent des experiences de diffusion isotherme, la diffusion sous gradient thermique et les effets de rayonnements sur les processus de diffusion. La plupart des donnees dignes de foi sur la diffusion dans les solides ont ete obtenues a partir de cas dans lesquels il n'y avait essentiellement pas de gradient de concentration des especes diffusantes. Toutefois, dans les systemes qui presentent un interet pour les specialistes du genie nucleaire, il y a presque invariablement des gradients de concentration. C'est pourquoi il faut avoir une connaissance pratique de la relation entre les coefficients d'autodiffusion et de diffusion chimique pour pouvoir determiner les coefficients applicables dans chaque cas d'espece. En outre, il faut egalement connaitre les coefficients d'activite thermodynamique en fonction de la composition. Recemment, il a ete clairement demontre qu'il est dangereux d'utiliser aveuglement une expression d'Arrhenius pour decrire les variations de la diffusion selon la temperature, car cela peut entrainer des erreurs considerables dans le calcul theorique des coefficients de diffusion. Les auteurs discutent les consequences qui en decoulent, particulierement pour les systemes cubiques centres refractaires. Ils ont etudie, tant theoriquement qu'experimentalement, l'effet d'un gradient thermique sur la distribution des impuretes de substitution dans un metal. Ces travaux ont permis de mieux apprecier l'importance de cet effet dans des systemes presentant un interet du point de vue nucleaire. L'accroissement de la diffusion par les champs de rayonnements demeure toujours un probleme d'un interet reel. Les auteurs ont fait les premieres mesures directes de l'effet du bombardement par des particules rapides

  8. Nuclear magnetic resonance of iron-57 nuclei in local fields in yttrium and iron garnets; Resonance magnetique nucleaire des noyaux du fer 57 dans les champs locaux du grenat d'yttrium et de fer

    Energy Technology Data Exchange (ETDEWEB)

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

    1961-07-01

    We have demonstrated the nuclear resonance of {sup 57}Fe nuclei in the local field of each of the two magnetic sub-lattices of yttrium and iron garnets. The resonance frequencies and the relaxation times have been measured as a function of the temperature. (author) [French] Nous avons mis en evidence la resonance nucleaire des noyaux de {sup 57}Fe dans le champ local de chacun des deux sous-reseaux magnetiques du grenat d'yttrium et de fer. Les frequences de resonances et les temps de relaxation ont ete mesures en fonction de la temperature. (auteur)

  9. Can-rupture detection in gas-cooled nuclear reactors; La detection des ruptures de gaine dans les piles nucleaires refroidies par gaz

    Energy Technology Data Exchange (ETDEWEB)

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

    1965-07-01

    Can-rupture detection (DRG) is one important aspect of pile safety, more particularly so in the case of gas-cooled reactors. A rapid and sure detection constitutes also an improvement as far as the efficiency of electricity-producing nuclear power stations are concerned. Among the numerous can-rupture detection methods, that based on the measurement of the concentration of short-lived fission gases in the heat-carrying fluid has proved to be the most sensitive and the most rapid. A systematic study of detectors based on the electrostatic collection of the daughter products of fission gases has been undertaken with a view to equip the reactors EL 2, G 3, EDF 1, EDF 2 and EDF 3, the gas loops of PEGASE and EL 4. The different parameters are studied in detail in order to obtain a maximum sensitivity and to make it possible to construct detection devices having the maximum operational reliability and requiring the minimum maintenance. The primary applications of these devices are examined in the case of the above-mentioned reactors. (author) [French] La Detection des Ruptures de Gaines (D. R. G.) est un aspect important de la securite des piles et plus particulierement des piles refroidies par un gaz. Une detection rapide et sure constitue aussi un element d'amelioration du rendement des centrales nucleaires productrices d'energie electrique. Parmi les nombreuses methodes de detection des ruptures de gaines, la mesure de la concentration dans le fluide caloporteur des gaz de fission a vie courte s'est revelee comme la plus sensible et la plus rapide. Une etude systematique des detecteurs a collection electrostatique des descendants des gaz de fission a ete entreprise en vue d'equiper les piles EL 2, G 3, EDF 1, EDF 2 et EDF 3, les boucles a gaz de la pile Pegase et la pile EL 4. Les divers parametres sont etudies en detail pour obtenir une sensibilite maximum et permettre la realisation de dispositifs de detection ayant le maximum de securite de

  10. Can-rupture detection in gas-cooled nuclear reactors; La detection des ruptures de gaine dans les piles nucleaires refroidies par gaz

    Energy Technology Data Exchange (ETDEWEB)

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

    1965-07-01

    Can-rupture detection (DRG) is one important aspect of pile safety, more particularly so in the case of gas-cooled reactors. A rapid and sure detection constitutes also an improvement as far as the efficiency of electricity-producing nuclear power stations are concerned. Among the numerous can-rupture detection methods, that based on the measurement of the concentration of short-lived fission gases in the heat-carrying fluid has proved to be the most sensitive and the most rapid. A systematic study of detectors based on the electrostatic collection of the daughter products of fission gases has been undertaken with a view to equip the reactors EL 2, G 3, EDF 1, EDF 2 and EDF 3, the gas loops of PEGASE and EL 4. The different parameters are studied in detail in order to obtain a maximum sensitivity and to make it possible to construct detection devices having the maximum operational reliability and requiring the minimum maintenance. The primary applications of these devices are examined in the case of the above-mentioned reactors. (author) [French] La Detection des Ruptures de Gaines (D. R. G.) est un aspect important de la securite des piles et plus particulierement des piles refroidies par un gaz. Une detection rapide et sure constitue aussi un element d'amelioration du rendement des centrales nucleaires productrices d'energie electrique. Parmi les nombreuses methodes de detection des ruptures de gaines, la mesure de la concentration dans le fluide caloporteur des gaz de fission a vie courte s'est revelee comme la plus sensible et la plus rapide. Une etude systematique des detecteurs a collection electrostatique des descendants des gaz de fission a ete entreprise en vue d'equiper les piles EL 2, G 3, EDF 1, EDF 2 et EDF 3, les boucles a gaz de la pile Pegase et la pile EL 4. Les divers parametres sont etudies en detail pour obtenir une sensibilite maximum et permettre la realisation de dispositifs de detection ayant le maximum de securite de fonctionnement et le

  11. General trends in the use of uranium in the nuclear industry; Tendances generales d'emploi de l'uranium dans les industries nucleaires

    Energy Technology Data Exchange (ETDEWEB)

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

    1960-07-01

    It can be seen from a consideration of the development of the military and civil needs for uranium that, in the long run, the main outlet for the metal will be provided by its industrial applications. The technical uncertainties concerning the best method of producing atomic energy are still numerous and in fact reflect the hesitation in choosing one of two classes of fuel: that based on the metal and that based on the oxide. Four main factors should influence the choice: - the neutron reactivity and the enrichment of the uranium; - the operating temperature; - the resistance to radiation effects; - the chemical stability; but in actual fact, when the choice for a particular use has to be made, it will be another type of factor, such as the cost price, and weight and space considerations which will determine the choice of either metallic uranium or uranium oxide reactors. (author) [French] D'apres le developpement des besoins militaires ou civils en uranium, on voit que les usages industriels de ce metal constituent, a long terme, le debouche essentiel. Les incertitudes techniques, sur le procede optimum pour faire de l'energie nucleaire, restent nombreuses, et se traduisent finalement par une hesitation entre deux grandes classes de combustibles: ceux a base de metal et ceux a base d'oxyde: la preference a l'une ou l'autre de ces deux categories doit s'inspirer de quatre considerations: - la reactivite neutronique et l'enrichissement de l'uranium; - la temperature de fonctionnement; - la resistance aux effets du rayonnement; - la stabilite chimique; mais en definitive, lorsqu'il s'agira d'une application determinee, ce seront des considerations d'un autre ordre, comme le prix de revient, le poids et l'encombrement, qui determineront le choix entre piles a uranium metallique et piles a oxyde d'uranium. (auteur)

  12. Study relating to the physico-chemical behaviour of heavy water in nuclear reactors; Etudes relatives au comportement physico-chimique de l'eau lourde dans les reacteurs nucleaires

    Energy Technology Data Exchange (ETDEWEB)

    Chenouard, J; Dirian, G; Roth, E; Vignet, P; Platzer, R [Commissariat a l' Energie Atomique, Grenoble (France). Centre d' Etudes Nucleaires

    1959-07-01

    Chemical and isotope pollution, and radiolytic decomposition are the two most important ways in which heavy water becomes degraded in nuclear reactors. Chemical pollution has led to the creation of ion exchange purification loops specially designed for reactors: the report contains a description in detail of the application of this purification method in CEA research reactors, including the analysis required, results obtained, and their interpretation. The intelligence obtained on radiolytic decomposition with the same facilities is also discussed, as well as the recombination apparatus and control equipment utilized. Finally, investigation to date in the CEA on recombination circuits for power reactors is also discussed. (author) [French] Parmi les degradations subies par l'eau lourde dans les reacteurs nucleaires, les deux plus importantes sont la pollution chimique et isotopique et la decomposition radiolytique. La pollution chimique a conduit a mettre au point pour le cas particulier des reacteurs, des circuits d'epuration par echange d'ions. On decrit ici en detail la mise en oeuvre de cette methode dans les reacteurs de recherche du CEA; les controles qu'elle necessite, les resultats obtenus et leur interpretation. En ce qui concerne la dissociation radiolytique de l'eau, les renseignements obtenus sur ces memes reacteurs sont communiques, ainsi que les details des dispositifs de recombinaison et des moyens de controle. Enfin, on fait le point des etudes poursuivies au CEA sur ces memes problemes de recombinaison dans le cas des reacteurs de puissance. (auteur)

  13. Study relating to the physico-chemical behaviour of heavy water in nuclear reactors; Etudes relatives au comportement physico-chimique de l'eau lourde dans les reacteurs nucleaires

    Energy Technology Data Exchange (ETDEWEB)

    Chenouard, J.; Dirian, G.; Roth, E.; Vignet, P.; Platzer, R. [Commissariat a l' Energie Atomique, Grenoble (France). Centre d' Etudes Nucleaires

    1959-07-01

    Chemical and isotope pollution, and radiolytic decomposition are the two most important ways in which heavy water becomes degraded in nuclear reactors. Chemical pollution has led to the creation of ion exchange purification loops specially designed for reactors: the report contains a description in detail of the application of this purification method in CEA research reactors, including the analysis required, results obtained, and their interpretation. The intelligence obtained on radiolytic decomposition with the same facilities is also discussed, as well as the recombination apparatus and control equipment utilized. Finally, investigation to date in the CEA on recombination circuits for power reactors is also discussed. (author) [French] Parmi les degradations subies par l'eau lourde dans les reacteurs nucleaires, les deux plus importantes sont la pollution chimique et isotopique et la decomposition radiolytique. La pollution chimique a conduit a mettre au point pour le cas particulier des reacteurs, des circuits d'epuration par echange d'ions. On decrit ici en detail la mise en oeuvre de cette methode dans les reacteurs de recherche du CEA; les controles qu'elle necessite, les resultats obtenus et leur interpretation. En ce qui concerne la dissociation radiolytique de l'eau, les renseignements obtenus sur ces memes reacteurs sont communiques, ainsi que les details des dispositifs de recombinaison et des moyens de controle. Enfin, on fait le point des etudes poursuivies au CEA sur ces memes problemes de recombinaison dans le cas des reacteurs de puissance. (auteur)

  14. Some aspects of nuclear graphite production in France; Etude generale sur les graphites nucleaires produits en France

    Energy Technology Data Exchange (ETDEWEB)

    Gueron, J; Hering, H [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires; Legendre, A [Pechiney, 75 - Paris (France)

    1958-07-01

    1) Manufacturing: A summary and results on the CEA-Pechiney purification process are given. Variations in the preparation of green pastes and their effects on graphitized material are described. 2) Physical and mechanical properties: Results are given on: - Statistics of dimensional variatior products having square cross-section. - Statistical variation of thermal expansion coefficients and of electrical conductivity. - Density of normals to carbon layer planes and their connexion with thermal expansion. - Stress-strain cycles and conclusions drawn therefrom. - Mechanical resistance and gas permeability of items for supporting fuel elements. 3) Behaviour under radiation: Alteration under radiation of French graphites irradiated either in G1 pile or in experimental piles, and thermal annealing of those alterations, are given. (author)Fren. [French] 1) Fabrication: On resume le procede d'epuration CEA-PECHINEY, ainsi que diverses modalites de preparation des pates et on expose les resultats obtenus. 2) Proprietes physiques et mecaniques: On indique le resultat d'etudes sur: - la statistique des dimensions de produits a section carree. - celle des variations des coefficients de dilatation thermique et de la conductibilite electrique. - la densite des normales aux plans graphitiques et leur connexion avec la dilatation thermique. - la compression mecanique du graphite. - la solidite mecanique et la permeabilite aux gaz de pieces destinees a supporter des cartouches de combustible. 3) Tenue sous rayonnement: Modification sous rayonnement des graphites fran is irradies soit dans la pile G1, soit dans des piles experimentales, et guerison thermique de ces modifications. (auteur)

  15. Experimental measurements and mathematics; Les mesures experimentales et les mathematiques

    Energy Technology Data Exchange (ETDEWEB)

    Abraham, I.; Bruno, S.; Durand, O.; Gaillard, P.; Lagrange, J.M.; Lamy, F.; Peyrat, J.P. [CEA Bruyeres-le-Chatel, 91 (France); Choux, A.; Druoton, L.; Pascal, G.; Sulpice, F. [CEA Valduc, 21 - Is-sur-Tille (France); Busvelle, E.; Garnier, L. [Universite de Bourgogne, Lab. d' Electronique, Informatique et Image, 21 - Dijon (France); Gauthier, J.P. [Laboratoire des Sciences de l' Information et des Systemes, 83 - Toulon (France); Langevin, R. [Institut Mathematique de Bourgogne, 21 - Dijon (France)

    2011-01-15

    Many problems that appear in experimental works can be solved by using mathematical methods, from the conception phase to the interpretation of measurements. We illustrate the use of these methods at CEA-DAM by pointing out some examples in 3 typical domains: treatment of experimental data, geometrical controls of targets, and analysis of a huge quantity of data. (authors)

  16. Health physics problems in the context of the development of industrial uses of nuclear energy; Les problemes de radioprotection devant le developpement de l'utilisation industrielle de l'energie nucleaire

    Energy Technology Data Exchange (ETDEWEB)

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

    1964-07-01

    fate of radioactive ions in the hydrosphere may be determined. - experiments and studies linked with the possibilities for disposal a underground storage of wastes. All these studies cover a complementary field, that of radioprotection, which forms the necessary link between nuclear safety proper, which concerns the actual operation of nuclear installations and medical supervision which directly concerns the health of the individual and the population. At the same time each one of the Health Physics disciplines possesses an independence which increases their efficiency on the safety level. (authors) [French] Le developpement de l'utilisation industrielle de l'energie nucleaire a mis l'accent sur la necessite de promouvoir une doctrine rationnelle et coherente en matiere de securite des installations atomiques et plus particulierement en matiere de securite des sites nucleaires. Le but principal de la securite est de diminuer, voire d'annuler les risques d'irradiation ou de contamination des travailleurs et de la population, consecutifs au fonctionnement normal ou accidentel des installations. La securite est obtenue par la mise en oeuvre d'un ensemble complexe de moyens. Parmi ces moyens les auteurs considerent essentiellement ceux qui presentent une certaine independance a l'egard du type d'installation: moyens d'alerte et de mesure et leur mise en oeuvre - preparation psychologique et technique des individus - evaluation de la capacite d'un site a absorber les rejets radioactifs sans dommage pour la population. Il est clair en effet que les consequences d'un accident sont diminuees par l'augmentation de la valeur des moyens de surveillance, de mesure et d'alerte, l'elevation du niveau technique et l'entrainement du personnel, l'education de la population. Ceci est particulierement vrai aupres d'une installation nucleaire ou l'etude des dangers presente un caractere abstrait et

  17. Health physics problems in the context of the development of industrial uses of nuclear energy; Les problemes de radioprotection devant le developpement de l'utilisation industrielle de l'energie nucleaire

    Energy Technology Data Exchange (ETDEWEB)

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

    1964-07-01

    fate of radioactive ions in the hydrosphere may be determined. - experiments and studies linked with the possibilities for disposal a underground storage of wastes. All these studies cover a complementary field, that of radioprotection, which forms the necessary link between nuclear safety proper, which concerns the actual operation of nuclear installations and medical supervision which directly concerns the health of the individual and the population. At the same time each one of the Health Physics disciplines possesses an independence which increases their efficiency on the safety level. (authors) [French] Le developpement de l'utilisation industrielle de l'energie nucleaire a mis l'accent sur la necessite de promouvoir une doctrine rationnelle et coherente en matiere de securite des installations atomiques et plus particulierement en matiere de securite des sites nucleaires. Le but principal de la securite est de diminuer, voire d'annuler les risques d'irradiation ou de contamination des travailleurs et de la population, consecutifs au fonctionnement normal ou accidentel des installations. La securite est obtenue par la mise en oeuvre d'un ensemble complexe de moyens. Parmi ces moyens les auteurs considerent essentiellement ceux qui presentent une certaine independance a l'egard du type d'installation: moyens d'alerte et de mesure et leur mise en oeuvre - preparation psychologique et technique des individus - evaluation de la capacite d'un site a absorber les rejets radioactifs sans dommage pour la population. Il est clair en effet que les consequences d'un accident sont diminuees par l'augmentation de la valeur des moyens de surveillance, de mesure et d'alerte, l'elevation du niveau technique et l'entrainement du personnel, l'education de la population. Ceci est particulierement vrai aupres d'une installation nucleaire ou l'etude des dangers presente un caractere abstrait et ou les moyens technologiques de protection sont multiples et complexes. Les etudes de

  18. The behaviour of some polyatomic gases in nuclear reactors; Le comportement de quelques gaz polyatomiques dans les reacteurs nucleaires

    Energy Technology Data Exchange (ETDEWEB)

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

    1958-07-01

    'influence des radiations. La radiolyse de NH{sub 3}, procede par un mecanisme complexe, et la cinetique obeit a une loi d'ordre 2,5 environ qui augmente avec le taux de decomposition. La decomposition de l'hydrogene sulfure est notablement plus rapide que celle de NH{sub 3}. Le seul produit gazeux de la reaction est l'hydrogene. Le soufre, qui se depose sur les parois des ampoules, est nettement perceptible a l'oeil. On a obtenu jusqu'ici des decompositions allant jusqu'a 84 pour cent. L'influence de la reaction {sup 32}S (n, p) {sup 32}P est consideree. La decomposition radiochimique du protoxyde d'azote N{sub 2}O se fait avec des rendements eleves. La reaction est compliquee des ses debuts par la formation d'oxydes superieurs de l'azote que nous identifions et mesurons. Le methane donne par decomposition radiochimique des quantites d'hydrocarbures superieurs. Certains de ces systemes gazeux pourraient trouver des applications dans la mesure de fortes doses de rayonnement. Ce probleme est discute en conclusion. (auteur)

  19. Exotic nuclei: another aspect of nuclear structure; Les noyaux exotiques: un autre regard sur la structure nucleaire

    Energy Technology Data Exchange (ETDEWEB)

    Dobaczewski, J [Warsaw Univ., Institute of Theoretical Physics (Poland); Blumenfeld, Y; Flocard, H; Garcia Borge, M J; Nowacki, F; Rombouts, S; Theisen, Ch; Marques, F M; Lacroix, D; Dessagne, P; Gaeggeler, H

    2002-07-01

    This document gathers the lectures made at the Joliot Curie international summer school in 2002 whose theme that year was exotic nuclei. There were 11 contributions whose titles are: 1) interactions, symmetry breaking and effective fields from quarks to nuclei; 2) status and perspectives for the study of exotic nuclei: experimental aspects; 3) the pairing interaction and the N = Z nuclei; 4) borders of stability region and exotic decays; 5) shell structure of nuclei: from stability to decay; 6) variational approach of system with a few nucleons; 7) from heavy to super-heavy nuclei; 8) halos, molecules and multi-neutrons; 9) macroscopic approaches for fusion reactions; 10) beta decay: a tool for spectroscopy; 11) the gas phase chemistry of super-heavy elements.

  20. Excitations in superfluid systems: contributions of the nuclear structure; Excitations dans les systemes superfluides: contributions de la structure nucleaire

    Energy Technology Data Exchange (ETDEWEB)

    Khan, E

    2005-12-15

    The author presents successively the theoretical aspect, the experimental aspect and the applied aspect of excitations in nuclear structures. The quasi-particle random phase approximation (QRPA) tool is first described. Recent approaches on QRPA are based on the theory of the density function where the ground state and excited states are described from the same nucleon-nucleon interaction. 2 methods for measuring the collective excitations are then presented: the proton scattering that has the potentiality to investigate the evolution of magicity, the second method is in fact a new method for measuring the giant mono-polar resonance (GMP) in exotic nuclei. Nuclear reactions are considered as a compulsory step on the way from observables like cross-sections to nuclear structure. The author highlights the assets of the convolution model that can generate the optical potential from the effective nucleon-nucleon interaction and from proton and neutron densities of the nuclei involved. R-processes in nucleosynthesis and neutron stars are reviewed as applications of collective excitations in the field of nuclear astrophysics. (A.C.)

  1. Comparative Studies of Chemical Effects following Nuclear Reactions and Transformations on Metal Organic Phenyl Compounds; Etudes Comparatives des Effets Chimiques Induits par les Reactions et les Transformations Nucleaires sur des Composes Phenylmetalliques; 0421 0420 0410 0414 ; Estudios Comparativos de los Efectos Quimicos de las Reacciones y Transformaciones Nucleares en Compuestos Fenil-Organometalicos

    Energy Technology Data Exchange (ETDEWEB)

    Merz, E.; Riedel, H. J. [Kernforschungsanlage, Juelich, Federal Republic of Germany (Germany)

    1965-04-15

    molecule by the nuclear recoil and the resulting excitation. The hypothesis is put forward that the kind and quantity of certain new radioactive species produced in connection with nuclear events is less a function of the nature and concentration of primary recoil fragments than are the ions, radicals and lattice defects imparted to the irradiated materials by secondary recoil effects (elastic and inelastic interactions) , including the peculiar influence of oxygen. (author) [French] Les auteurs ont etudie les effets chimiques provoques par les atomes chaud de recul resultant des reactions nucleaires dans les solides et dans les liquides en se fondant sur une vaste comparaison des produits des processus (n,{gamma}) et (n,2n) dans les composes phenyles du germanium, de l'etain, du plomb, de l'arsenic et de l'antimoine. En outre, ils ont compare les produits de recul radioactifs formes apres capture K dans le tetraphenyl- germanium-{sup 68}Ge avec les resultats du processus (n,{gamma}) dans le triphenylgalliumet du processus (n,p) sur le tetraphenylgermanium. Enfin, ils ont etudie la transition {beta}{sup -} dans laquelle {sup 77}Ge est remplace par {sup 77}As dans le compose. En appliquant differentes methodes de separation, par exemple la chromatographie d'adsorption sur alumine, l'echange d'ions et l'electrophorese, ils ont separe les divers produits de recul radioactifs et determine les rendements individuels. Ils ont constate que, dans les reactions nucleaires, les composes des metaux cites ayant des coordinats identiques forment pratiquement les memes classes.de produits de recul. Toutefois, pour la distribution des rendements, il y a des differences caracteristiques entre la reaction (n,{gamma}) et la reaction (n,2n). L'influence sur les rendements est a peine perceptible lorsque les irradiations ont lieu dans des liquides ou des solutions. Mais les differences trouvees pour les nouveaux composes formes par des transformations nucleaires sont frappantes, en ce qui

  2. Integration of the nuclear energy among the production facilities of energy in France; Integration de l'energie nucleaire parmi les moyens de production de l'energie en france

    Energy Technology Data Exchange (ETDEWEB)

    Ailleret, P [Electricite de France (EDF), 75 - Paris (France). Direction des Etudes et Recherches; Taranger, P [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1955-07-01

    The present report gives an overview of the present facilities of energy productions in France and their perspectives. the electric production comes for half about power stations hydraulics and for half of thermal power stations. However due to the increase of the energy consumption, France is particularly interested by the atomic energy that appears to bring a supply in due time to the hydraulics and to limit a development of the thermal power stations to which the natural resources of France in classic fuel would not permit to cope presumably. The integration of the nuclear plants to the other production facilities will make itself gradually according to the evolution of the energy needs. (M.B.) [French] Le present rapport donne un apercu des moyens actuels de productions energetiques en France et de ses perspectives. la production electrique provient pour moitie environ de centrales hydraulique et pour moitie de centrales thermiques. Cependant face a l'augmentation de la consommation energetique, la France est tres particulierement interessee par l'energie atomique qui parait devoir apporter en temps utile la releve a l'hydraulique et limiter un developpement des centrales thermiques auxquels les ressources naturelles de la France en combustible classique ne permettraient vraisemblablement pas de faire face. L'integration des centrales nucleaires aux autres moyens de production se fera graduellment en fonction de l'evolution des besoins energetiques. (M.B.)

  3. Contribution to the study of the action of electromagnetic fields on the angular correlations of nuclear radiation (1960); Contribution a l'etude de l'action des champs electromagnetiques sur les correlations angulaires des rayonnements nucleaires (1960)

    Energy Technology Data Exchange (ETDEWEB)

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

    1959-01-15

    This work deals with the study of interaction of E.M. fields with nuclear moments of nuclei emitting gamma rays. We describe first experiments on delayed angular correlation showing the role played by statistic quadrupole interaction. We have measured the magnetic moment of the second excited state of {sup 19}F using an external magnetic field. In the case of {sup 19}O, experiments of angular distributions and angular correlations of gamma -rays taking into account the possibility of perturbations, allow us to determine the spin and parities of the three first levels. (author) [French] Le present travail concerne l'etude de l'interaction des champs electromagnetiques et des moments nucleaires de noyaux emettant des rayonnements gamma. Nous decrivons des experiences de correlation angulaire differee dont l'interpretation met en coincidence le role joue par les interactions quadrupolaires statiques. Nous avons mesure le moment magnetique de {sup 19}F dans un etat excite en utilisant un champ magnetique exterieur a la source radioactive. Enfin, dans le cas de {sup 19}O, nous montrons l'utilite d'un examen des possibilites de perturbations dans l'interpretation des resultats fournis par des correlations ou des distributions angulaires. (auteur)

  4. Contribution to the study of the action of electromagnetic fields on the angular correlations of nuclear radiation (1960); Contribution a l'etude de l'action des champs electromagnetiques sur les correlations angulaires des rayonnements nucleaires (1960)

    Energy Technology Data Exchange (ETDEWEB)

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

    1959-01-15

    This work deals with the study of interaction of E.M. fields with nuclear moments of nuclei emitting gamma rays. We describe first experiments on delayed angular correlation showing the role played by statistic quadrupole interaction. We have measured the magnetic moment of the second excited state of {sup 19}F using an external magnetic field. In the case of {sup 19}O, experiments of angular distributions and angular correlations of gamma -rays taking into account the possibility of perturbations, allow us to determine the spin and parities of the three first levels. (author) [French] Le present travail concerne l'etude de l'interaction des champs electromagnetiques et des moments nucleaires de noyaux emettant des rayonnements gamma. Nous decrivons des experiences de correlation angulaire differee dont l'interpretation met en coincidence le role joue par les interactions quadrupolaires statiques. Nous avons mesure le moment magnetique de {sup 19}F dans un etat excite en utilisant un champ magnetique exterieur a la source radioactive. Enfin, dans le cas de {sup 19}O, nous montrons l'utilite d'un examen des possibilites de perturbations dans l'interpretation des resultats fournis par des correlations ou des distributions angulaires. (auteur)

  5. Siloette, Siloe mock-up; Siloette, modele nucleaire de siloe

    Energy Technology Data Exchange (ETDEWEB)

    Delcroix, V; Jeanne, G; Mitault, G; Schulhof, P [Commissariat a l' Energie Atomique, Grenoble (France). Centre d' Etudes Nucleaires

    1964-07-01

    Siloette is the Siloe mock-up. The main installations are described: various tanks, building, auxiliaries, control systems... Precis ions are given about precautions taken for using spent fuel elements. (authors) [French] Siloette est le modele nucleaire de SILOE. On decrit ses diverses installations: bassins, batiments, auxiliaires, controle... Des precisions sont donnees sur les precautions prises pour y utiliser des elements uses. (auteurs)

  6. Study of thick, nuclear-compensated silicon detectors; Etude des detecteurs epais au silicium compense nucleairement

    Energy Technology Data Exchange (ETDEWEB)

    Le Coroller, Y. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1964-09-01

    A study is made here, from the point of view of the realization and the performance, of thick nuclear-compensated silicon detectors. After recalling the need for compensation and reviewing the existing methods, the author describes in detail the controlled realization of thick detectors by nuclear compensation from the theoretical and experimental points of view. The practical precautions which should be observed are given: control of the homogeneity of the starting material, control of the evolution of the compensation, elimination of parasitic processes. The performances of the detectors obtained are then studied: electrical characteristics (current, life-time) on the one hand, detection and spectrometry of penetrating radiations on the other hand. The results show, that the compensated diodes having an effective thickness of two millimeters operate satisfactorily as detectors for applied voltages of about 500 volts. The resolutions observed are then about 2 per cent for mono-energetic electrons and about 4 per cent for the gamma; they can be improved by the use of a pre-amplifier of very low background noise. (author) [French] Les detecteurs epais au silicium compense nucleairement sont etudies ici du double point de vue realisation et performances. Apres un rappel sur la necessite de la compensation et les procedes existants, la realisation controlee des detecteurs epais par compensation nucleaire est decrite en detail sous l'aspect theorique et l'aspect experimental. On met en evidence les precautions a prendre dans la pratique: controle de l'homogeneite du materiau de base, controle de l'evolution de la compensation, elimination des processus parasites. On etudie ensuite les performances de detecteurs obtenus : caracteristiques electriques (courant, duree de vie) d'une part, d'autre part detection et spectrometrie des rayonnements penetrants. Les resultats montrent que les diodes compensees ayant une epaisseur utile de deux

  7. Study of thick, nuclear-compensated silicon detectors; Etude des detecteurs epais au silicium compense nucleairement

    Energy Technology Data Exchange (ETDEWEB)

    Le Coroller, Y [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1964-09-01

    A study is made here, from the point of view of the realization and the performance, of thick nuclear-compensated silicon detectors. After recalling the need for compensation and reviewing the existing methods, the author describes in detail the controlled realization of thick detectors by nuclear compensation from the theoretical and experimental points of view. The practical precautions which should be observed are given: control of the homogeneity of the starting material, control of the evolution of the compensation, elimination of parasitic processes. The performances of the detectors obtained are then studied: electrical characteristics (current, life-time) on the one hand, detection and spectrometry of penetrating radiations on the other hand. The results show, that the compensated diodes having an effective thickness of two millimeters operate satisfactorily as detectors for applied voltages of about 500 volts. The resolutions observed are then about 2 per cent for mono-energetic electrons and about 4 per cent for the gamma; they can be improved by the use of a pre-amplifier of very low background noise. (author) [French] Les detecteurs epais au silicium compense nucleairement sont etudies ici du double point de vue realisation et performances. Apres un rappel sur la necessite de la compensation et les procedes existants, la realisation controlee des detecteurs epais par compensation nucleaire est decrite en detail sous l'aspect theorique et l'aspect experimental. On met en evidence les precautions a prendre dans la pratique: controle de l'homogeneite du materiau de base, controle de l'evolution de la compensation, elimination des processus parasites. On etudie ensuite les performances de detecteurs obtenus : caracteristiques electriques (courant, duree de vie) d'une part, d'autre part detection et spectrometrie des rayonnements penetrants. Les resultats montrent que les diodes compensees ayant une epaisseur utile de deux millimetres fonctionnent

  8. Some problems on the aqueous corrosion of structural materials in nuclear engineering; Problemes de corrosion aqueuse de materiaux de structure dans les constructions nucleaires

    Energy Technology Data Exchange (ETDEWEB)

    Coriou, H; Grall, L [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1964-07-01

    The purpose of this report is to give a comprehensive view of some aqueous corrosion studies which have been carried out with various materials for utilization either in nuclear reactors or in irradiated fuel treatment plants. The various subjects are listed below. Austenitic Fe-Ni-Cr alloys: the behaviour of austenitic Fe-Ni-Cr alloys in nitric medium and in the presence of hexavalent chromium; the stress corrosion of austenitic alloys in alkaline media at high temperatures; the stress corrosion of austenitic Fe-Ni-Cr alloys in 650 C steam. Ferritic steels: corrosion of low alloy steels in water at 25 and 360 C; zirconium alloys; the behaviour of ultrapure zirconium in water and steam at high temperature. (authors) [French] On presente un ensemble d'etudes de corrosion en milieu aqueux effectuees sur des materiaux utilises, soit dans la construction des reacteurs soit pour la realisation des usines de traitement des combustibles irradies. Les differents sujets etudies sont les suivants. Les alliages austenitiques Fer-Nickel-Chrome: comportement d'alliages austenitiques fer-nickel-chrome en milieu nitrique en presence de chrome hexavalent; Corrosion sous contrainte d'alliages austenitiques dans les milieux alcalins a haute temperature; Corrosion sous contrainte dans la vapeur a 650 C d'alliages austenitiques fer-nickel-chrome. Les aciers ferritiques; Corrosion d'aciers faiblement allies dans l'eau a 25 et 360 C; le zirconium et ses alliages; Comportement du zirconium tres pur dans l'eau et la vapeur a haute temperature. (auteurs)

  9. Contribution to the experimental survey of the nuclear isomerism. Application of the deferred coincidences method to research and to the survey of metastable states of short period; Contribution a l'etude experimentale de l'isomerie nucleaire. Application de la methode des coincidences differees a la recherche et a l'etude d'etats metastables de periode courte

    Energy Technology Data Exchange (ETDEWEB)

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

    1953-06-15

    Various methods of the physics brought many informations on the nuclear elements which one can arrange some ponderable quantities, what is the case of the steady elements and some, unsteady elements, as most of natural radioelements. On the other hand, elements of shorter life duration, and notably those that are carried to an excited state, are more badly known, and one can get information to their consideration that by the mediator of the properties of the transitions that they undergo, when they give birth has best-known nuclear cash: among these transitions represent the isomeric transitions. The goal of this work is the survey of the isomeric transitions from metastable states of short period, included in the domain of the microsecond to some milliseconds. The method of the deferred coincidences has been put to the point and applied in this goal while using the advantages of the selectors to several channels, under two main aspects where the device to several channels was either a selector of time, either a selector of amplitudes. This method served to study the working of Geiger-Muller counter and to measure with precision the period of {sup 181}Ta{sup *} in of the varied experimental conditions. The adopted value is 17,2 {+-}0,2 {mu}s. This work also found an immediate practical application to the setting in evidence of very weak quantities of hafnium in zirconium, of which it constitutes a tenacious and difficult impurity to analyze by the ordinary ways. (M.B.) [French] Les diverses methodes de la physique ont apporte de nombreux renseignements sur les especes nucleaires dont on peut disposer en quantites ponderables, ce qui est le cas des especes stables et de certaines especes instables, comme la plupart des radioelements naturels. Par contre, les noyaux de duree de vie plus courte, et notamment ceux qui sont portes a un etat excite, sont plus mal connus, et on ne peut obtenir de renseignements a leur egard que par l'intermediaire des proprietes des

  10. Calculation of the shock-wave in the region close to an underground nuclear explosion (method Cades); Calcul de l'onde de choc en zone proche d'une explosion nucleaire souterraine (methode cades)

    Energy Technology Data Exchange (ETDEWEB)

    Supiot, F; Brugies, J [Commissariat a l' Energie Atomique, Bruyeres-le-Chatel (France). Centre d' Etudes

    1969-07-01

    The outline of a method is presented for calculating the characteristics of a shock wave produced by an underground nuclear explosion (pressure, wave velocity, velocity of the medium, energy left in the medium by the shock, etc.). By means of an application to a granitic medium and of a comparison with results obtained during French nuclear explosions, it has been possible to show the good agreement existing between the calculations and the experimental results. The advantages of such a method for studying the industrial applications of underground nuclear explosions are stressed. (authors) [French] On expose les grandes lignes d'une methode de calcul des caracteristiques de l'onde de choc issue d'une explosion nucleaire souterraine (pression, vitesse de l'onde, vitesse du milieu, energie deposee par le choc dans le milieu...). Une application a un milieu granitique et une comparaison aux resultats obtenus au cours d'explosions nucleaires francaises permet de montrer la bonne concordance entre le calcul et les resultats experimentaux. On souligne l'interet d'une telle, methode pour l'etude d'applications industrielles des explosions nucleaires souterraines. (auteurs)

  11. RANS / LES coupling applied to high Reynolds number turbulent flows of the nuclear industry; Application du couplage RANS / LES aux ecoulements turbulents a haut nombre de Reynolds de l'industrie nucleaire

    Energy Technology Data Exchange (ETDEWEB)

    Benarafa, Y

    2005-12-15

    The main issue to perform a computational study of high Reynolds numbered turbulent flows consists on predicting their unsteadiness without implying a tremendous computational cost. First, the main drawbacks of large-eddy simulation with standard wall model on a coarse mesh for a plane channel flow are highlighted. To correct these drawbacks two coupling RANS/LES methods have been proposed. The first one relies on a sophisticated wall model (TBLE) which consists on solving Thin Boundary Layer Equations with a RANS type turbulent closure in the near wall region. The second one consists on a RANS/LES methods have been proposed. The second one consists on a RANS/LES coupling method using a forcing term approach. These various approaches have been implemented in the TRIO-U code developed at CEA (French Atomic Center) at Grenoble, France. The studied flow configurations are the fully developed plane channel flow and a flow around a surface-mounted cubical obstacle. Both approaches provide encouraging results and allow a surface-mounted cubical obstacle. Both approaches provide encouraging results and allow unsteady simulations for a low computational cost. (author)

  12. Research means to back the development of nuclear reactors; Les moyens de recherche en support a l'evolution des reacteurs nucleaires

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2005-07-01

    After 50 year long feedback experience on nuclear reactor operations it is legitimate to wonder whether experimental facilities used to support nuclear power programs are still necessary. The various participants of this conference said yes for mainly 4 reasons: -) to validate the extension of the service life of a reactor without putting at risk its high safety standard, -) to give the reactor more flexibility to cope with the power demand, -) to confront the results given by computerized simulations with experimental data, and -) to qualify the nuclear systems of tomorrow. (A.C.)

  13. Communication Received from Certain Member States Regarding Guidelines for Transfers of Nuclear-related Dual-use Equipment, Material, Software and Related Technology; Communication recue de certains Etats Membres concernant les directives applicables aux transferts d'equipements, de matieres et de logiciels a double usage dans le domaine nucleaire, ainsi que de technologies connexes

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2010-09-09

    The Agency has received a Note Verbale from the Permanent Mission of Hungary, dated 14 June 2010, in which it requests that the Agency circulate to all Member States a letter of 7 May 2010 from the Chairman of the Nuclear Suppliers Group, Ambassador Ms. Gyorgyi Martin Zanathy, to the Director General, on behalf of the Governments of Argentina, Australia, Austria, Belarus, Belgium, Brazil, Bulgaria, Canada, China, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Japan, Kazakhstan, Republic of Korea, Latvia, Lithuania, Luxemburg, Malta, Netherlands, New Zealand, Norway, Poland, Portugal, Romania, Russian Federation, Slovakia, Slovenia, South Africa, Spain, Sweden, Switzerland, Turkey, Ukraine, the United Kingdom of Great Britain and Northern Ireland and the United States of America,1 providing further information on those Governments' Guidelines for Nuclear Transfers [French] L'Agence a recu une note verbale de la mission permanente de la Hongrie, en date du 14 juin 010, lui demandant de communiquer a tous les Etats Membres une lettre du 7 mai 2010 du president du Groupe des fournisseurs nucleaires, l'ambassadeur Gyorgyi Martin Zanathy, adressee au Directeur general au nom des gouvernements des Etats suivants : Afrique du Sud, Allemagne, Argentine, Australie, Autriche, Belarus, Belgique, Bresil, Bulgarie, Canada, Chine, Croatie, Chypre, Danemark, Espagne, Estonie, Etats-Unis d'Amerique, Federation de Russie, Finlande, France, Grece, Hongrie, Irlande, Islande, Italie, Japon, Kazakhstan, Lettonie, Lituanie, Luxembourg, Malte, Norvege, Nouvelle-Zelande, Pays-Bas, Pologne, Portugal, Republique de Coree, Republique tcheque, Roumanie, Royaume-Uni de Grande-Bretagne et d'Irlande du Nord, Slovaquie, Slovenie, Suede, Suisse, Turquie et Ukraine1. Cette lettre apporte des informations supplementaires sur les Directives de ces gouvernements applicables aux transferts nucleaires.

  14. Communication Received from the Permanent Mission of Brazil regarding Certain Member States' Guidelines for the Export of Nuclear Material, Equipment and Technology; Communication recue de la mission permanente du Bresil concernant les Directives de certains Etats Membres applicables a l'exportation de matieres, d'equipements et de technologie nucleaires

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2007-12-03

    The Agency has received a Note Verbale from the Permanent Mission of Brazil, dated 22 March 2007, in which it requests that the Agency circulate to all Member States a letter of 12 December 2006 from the Chairman of the Nuclear Suppliers Group, Ambassador Jose Artur Denot Medeiros, to the Director General, on behalf of the Governments of Argentina, Australia, Austria, Belarus, Belgium, Brazil, Bulgaria, Canada, China, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Ireland, Italy, Japan, Kazakhstan, Republic of Korea, Latvia, Lithuania, Luxemburg, Malta, Netherlands, New Zealand, Norway, Poland, Portugal, Romania, Russian Federation, Slovakia, Slovenia, South Africa, Spain, Sweden, Switzerland, Turkey, Ukraine, the United Kingdom of Great Britain and Northern Ireland and the United States of America, providing further information on those Governments' Guidelines for Nuclear Transfers [French] L'Agence a recu une note verbale de la mission permanente du Bresil, en date du 22 mars 2007, lui demandant de diffuser a tous les Etats Membres une lettre du 12 decembre 2006 du president du Groupe des fournisseurs nucleaires, l'ambassadeur Artur Denot Medeiros, adressee au Directeur general au nom des gouvernements des Etats suivants : Afrique du Sud, Allemagne, Argentine, Australie, Autriche, Belarus, Belgique, Bresil, Bulgarie, Canada, Chine, Chypre, Croatie, Danemark, Espagne, Estonie, Etats-Unis d'Amerique, Federation de Russie, Finlande, France, Grece, Hongrie, Irlande, Italie, Japon, Kazakhstan, Lettonie, Lituanie, Luxembourg, Malte, Norvege, Nouvelle-Zelande, Pays-Bas, Pologne, Portugal, Republique de Coree, Republique tcheque, Roumanie, Royaume-Uni de Grande-Bretagne et d'Irlande du Nord, Slovaquie, Slovenie, Suede, Suisse, Turquie et Ukraine. Cette lettre apporte des informations supplementaires sur les Directives de ces gouvernements applicables aux transferts nucleaires.

  15. Communication Received from the Permanent Mission of the Netherlands regarding Certain Member States' Guidelines for the Export of Nuclear Material, Equipment and Technology; Communication recue de la mission permanente des Pays-Bas concernant les Directives de certains Etats Membres applicables a l'exportation de matieres, d'equipements et de technologie nucleaires

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2011-09-05

    The Agency has received a Note Verbale from the Permanent Mission of the Kingdom of the Netherlands, dated 12 July 2011, in which it requests that the Agency circulate to all Member States a letter of 12 July 2011 from the Chairman of the Nuclear Suppliers Group, Ambassador Piet de Klerk, to the Director General, on behalf of the Governments of Argentina, Australia, Austria, Belarus, Belgium, Brazil, Bulgaria, Canada, China, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Japan, Kazakhstan, Republic of Korea, Latvia, Lithuania, Luxembourg, Malta, the Netherlands, New Zealand, Norway, Poland, Portugal, Romania, Russian Federation, Slovakia, Slovenia, South Africa, Spain, Sweden, Switzerland, Turkey, Ukraine, the United Kingdom of Great Britain and Northern Ireland and the United States of America, providing further information on those Governments' Guidelines for Nuclear Transfers [French] L'Agence a recu une note verbale de la mission permanente du Royaume des Pays-Bas, en date du 12 juillet 2011, lui demandant de communiquer a tous les Etats Membres une lettre du 12 juillet 2011 du president du Groupe des fournisseurs nucleaires, l'ambassadeur Piet de Klerk, adressee au Directeur general au nom des gouvernements des Etats suivants : Afrique du Sud, Allemagne, Argentine, Australie, Autriche, Belarus, Belgique, Bresil, Bulgarie, Canada, Chine, Croatie, Chypre, Danemark, Espagne, Estonie, Etats-Unis d'Amerique, Federation de Russie, Finlande, France, Grece, Hongrie, Irlande, Islande, Italie, Japon, Kazakhstan, Lettonie, Lituanie, Luxembourg, Malte, Norvege, Nouvelle-Zelande, Pays-Bas, Pologne, Portugal, Republique de Coree, Republique tcheque, Roumanie, Royaume-Uni de Grande-Bretagne et d'Irlande du Nord, Slovaquie, Slovenie, Suede, Suisse, Turquie et Ukraineb. Cette lettre apporte des informations supplementaires sur les Directives de ces gouvernements applicables aux transferts nucleaires.

  16. The atolls of Mururoa and Fangataufa (French Polynesia). The nuclear testings. Radiological aspects; Les atolls de Mururoa et de Fangataufa (Polynesie Francaise). Les experimentations nucleaires. Aspects radiologiques

    Energy Technology Data Exchange (ETDEWEB)

    Martin, G

    2007-07-01

    This report provides a review of the radiological measures implemented during the thirty year period of French nuclear tests in Polynesian atolls of Mururoa and Fangataufa. It presents full details of the practices deployed throughout these tests, including, in particular, aspects concerning radiological protection for the population and the environment. It contains all the scientific results and measurements of radioactivity performed during this period, providing concrete facts that can be used to assess the consequences these tests have had on the personnel involved, the population and the environment. (author)

  17. Catalytic Activity and Nuclear Radiation; L'activite catalytique et les rayonnements nucleaires; Kataliticheskaya aktivnost' i yadernoe izluchenie; La actividad catalitica y las radiaciones nucleares

    Energy Technology Data Exchange (ETDEWEB)

    Turkevich, J.; Ikawa, T.; Nozaki, F.; Stamires, D. [Princeton University, N.J (United States)

    1963-11-15

    New work is to be presented on the effect of gamma radiation on the catalytic activity of alumina silica gel and decationateii molecular sieves of the Linde Y-type. A graded set of alumina silica coprecipitated gel catalysts have been made with the atomic ratio of alumina silica having ten different equally spaced values. Another set of catalysts was made by partially replacing the sodium of a Linde molecular Y-sieve Na{sub 56}(AlO{sub 2}){sub 56}(SiO{sub 2}){sub 126} by ammonium ion and then decomposing it to drive both the ammonia and the water away to produce a de-cationated position in the sieve: A graded set of such catalysts has been prepared containing varying amounts of these de-cationated sites from zero to 100% of the original sodium content. These two sets of catalysts have been characterized for catalytic activity before and after gamma radiation by studying the kinetics of cumene decomposition into benzene and propylene, the double bond isomerization of butene-1 to butene-2 and the hydrogen/deuterium exchange reaction. The number of active sites was determined by progressive poisoning using quinoline and the activity per site was thus characterized. The materials were also studied by measuring the electron spin resonance of adsorbed electron transfer agents such as triphenylamine, perylen'e and symmetrical diphenyl ethylene. The ability to transfer electrons was found to be parallel to catalytic activity. Proton resonance of adsorbed water was'used to characterize the nature of the catalytic site. (author) [French] Les auteurs se proposent de presenter des recherches nouvelles consacrees aux effets des rayons gamma sur l'activite catalytique du gel de silice et d'alumine et des tamis moleculaires decationises du type Linde Y. Pour cela ils ont prepare une serie de catalyseurs en coprecipitant de la silice et de l'alumine dans des proportions successivement egales a dix nombres regulierement espaces. Ils ont prepare une deuxieme serie de catalyseurs en

  18. High-resolution nuclear magnetic resonance of quadrupolar nuclei in solids; Resonance magnetique nucleaire haute-resolution des noyaux quadrupolaires dans les solides

    Energy Technology Data Exchange (ETDEWEB)

    Charpentier, Th

    1998-10-23

    After a brief review of existing methods in high-resolution NMR of quadrupolar nuclei, the manipulation of multi-quantum coherencies by radiofrequency pulses is studied. Results are then applied to the determination of optimal conditions for performing the recently introduced multiple-quantum magic-angle experiment (MQMAS). The principles of this new method, the different pulse sequences and the data processing are described in detail. Applications on aluminum hydrates and cement pastes show the improvements of this new technique over the previous ones. In a second part, after an investigation of the Floquet theory, a new formalism has been devised for studying the behavior of a spin submitted to a strong quadrupolar interaction and radiofrequency field in a rotating sample. This formalism is then applied to a quantitative study of the phenomenon of rotational induced adiabatic transfer of coherencies (RIACT). The extension of our theoretical approach to two-dimensional experiments provides a powerful tool for quantitative analyses of MQMAS spectra. Agreement between experimental data and simulations demonstrates the reliability of our approach. Preliminary results concerning the application of MQMAS spectroscopy, using our simulation programs, to structural study of amorphous materials are presented. The third and last part presents a theoretical and experimental investigation of dipolar order in a rotating sample. Two theoretical models are described, the first for the slow spinning speed regime where an adiabatic approximation can be made, and the second for the fast spinning speed regime. (author)

  19. Solubility of actinides and surrogates in nuclear glasses; Solubilite des actinides et de leurs simulants dans les verres nucleaires. Limites d'incorporation et comprehension des mecanismes

    Energy Technology Data Exchange (ETDEWEB)

    Lopez, Ch

    2003-07-01

    The nuclear wastes are currently incorporated in borosilicate glass matrices. The resulting glass must be perfectly homogeneous. The work discussed here is a study of actinide (thorium and plutonium) solubility in borosilicate glass, undertaken to assess the extent of actinide solubility in the glass and to understand the mechanisms controlling actinide solubilization. Glass specimens containing; actinide surrogates were used to prepare and optimize the fabrication of radioactive glass samples. These preliminary studies revealed that actinide Surrogates solubility in the glass was enhanced by controlling the processing temperature, the dissolution kinetic of the surrogate precursors, the glass composition and the oxidizing versus reducing conditions. The actinide solubility was investigated in the borosilicate glass. The evolution of thorium solubility in borosilicate glass was determined for temperatures ranging from 1200 deg C to 1400 deg C.Borosilicate glass specimens containing plutonium were fabricated. The experimental result showed that the plutonium solubility limit ranged from 1 to 2.5 wt% PuO{sub 2} at 1200 deg C. A structural approach based on the determination of the local structure around actinides and their surrogates by EXAFS spectroscopy was used to determine their structural role in the glass and the nature of their bonding with the vitreous network. This approach revealed a correlation between the length of these bonds and the solubility of the actinides and their surrogates. (author)

  20. Treatment of effluent at the Saclay Centre d'Etudes Nucleaires (1960); Le traitement des effluents du Centre d'Etudes Nucleaires de Saclay (1960)

    Energy Technology Data Exchange (ETDEWEB)

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

    1960-07-01

    The Centre d'Etudes Nucleaires at Saclay possesses several installations from which liquid radioactive effluent is rejected, and it has thus been found necessary to construct a station for the purification of radioactive liquids and to settle various chemical, analytical and technological problems. This report describes, in the following order: - the disposal possibilities at the Centre d'Etudes Nucleaires, Saclay, - the effluents produced at the centre, - the set-up for collecting effluent, - treatment of the effluent, - results of these treatments. (author) [French] La presence, au Centre d'Etudes Nucleaires de Saclay, de plusieurs installations susceptibles de rejeter des effluents liquides radioactifs a necessite la construction d'une station d'epuration d'eaux radioactives et la mise au point de differents problemes chimiques, analytiques et technologiques. Dans ce rapport, nous exposerons successivement: - les possibilites de rejet du Centre d'Etudes Nucleaires de Saclay, - les effluents du centre, - le dispositif de collecte des effluents, - le traitement de ces effluents, - les resultats de ces traitements. (auteur)

  1. Platinoids and molybdenum in nuclear waste containment glasses: a structural study; Les platinoides et le molybdene dans des verres d'interet nucleaires: etude structurale

    Energy Technology Data Exchange (ETDEWEB)

    Le Grand, M. [CEA/VALRHO - site de Marcoule, Dept. de Recherche en Retraitement et en Vitrification (DRRV), 30 - Marcoule (France)]|[Paris-7 Univ., 75 (France)

    2000-07-01

    This work deals with the structure of borosilicate nuclear glasses and with some relationships between structure and macroscopic properties. Two types of elements which may disturb the industrial process - platinoids (Ru and Pd) and molybdenum - are central to this work. Platinoids induce weak modifications on the structure of the glass, causing a depolymerization of the glassy network, an increase of the {sup [3]}B/{sup [4]}B ratio and a modification of the medium range order around Si between 3.3 and 4.5 angstrom. The modifications of viscosity and density induced by platinoids in the glass are not due to the structural effect of the platinoids. The increase of viscosity is attributed to needle shaped RuO{sub 2}. It can be moderated by imposing reducing conditions during the elaboration of the glass. The slight difference between experimental and calculated densities is due to the increase of the volume percentage of bubbles in the glass with increasing platinoid content. Mo is either present in the glass as molybdic groupings, or mobilized in chemically complex molybdic crystalline phases. The chemical composition and mineralogy of these phases has been obtained using electronic microprobe data and XRD with Rietveld analysis. The distribution of the different elements between the crystalline phases and the glass is strongly influenced by the structural role of the various cations in the glass. The Mo present in the glass appears as MoO{sub 4} tetrahedra, independent of the borosilicate network. The formation of the crystalline phases can be explained by the existence of a precursor in which the MoO{sub 4} tetrahedra are concentrated in rich alkali and earth-alkali bearing areas of the glass. (author)

  2. Platinoids and molybdenum in nuclear waste containment glasses: a structural study; Les platinoides et le molybdene dans des verres d'interet nucleaires: etude structurale

    Energy Technology Data Exchange (ETDEWEB)

    Le Grand, M [CEA/VALRHO - site de Marcoule, Dept. de Recherche en Retraitement et en Vitrification (DRRV), 30 - Marcoule (France); [Paris-7 Univ., 75 (France)

    2000-07-01

    This work deals with the structure of borosilicate nuclear glasses and with some relationships between structure and macroscopic properties. Two types of elements which may disturb the industrial process - platinoids (Ru and Pd) and molybdenum - are central to this work. Platinoids induce weak modifications on the structure of the glass, causing a depolymerization of the glassy network, an increase of the {sup [3]}B/{sup [4]}B ratio and a modification of the medium range order around Si between 3.3 and 4.5 angstrom. The modifications of viscosity and density induced by platinoids in the glass are not due to the structural effect of the platinoids. The increase of viscosity is attributed to needle shaped RuO{sub 2}. It can be moderated by imposing reducing conditions during the elaboration of the glass. The slight difference between experimental and calculated densities is due to the increase of the volume percentage of bubbles in the glass with increasing platinoid content. Mo is either present in the glass as molybdic groupings, or mobilized in chemically complex molybdic crystalline phases. The chemical composition and mineralogy of these phases has been obtained using electronic microprobe data and XRD with Rietveld analysis. The distribution of the different elements between the crystalline phases and the glass is strongly influenced by the structural role of the various cations in the glass. The Mo present in the glass appears as MoO{sub 4} tetrahedra, independent of the borosilicate network. The formation of the crystalline phases can be explained by the existence of a precursor in which the MoO{sub 4} tetrahedra are concentrated in rich alkali and earth-alkali bearing areas of the glass. (author)

  3. Contribution to the study of thermal-hydraulic problems in nuclear reactors; Contribution a l`etude de problemes de thermohydraulique dans les reacteurs nucleaires

    Energy Technology Data Exchange (ETDEWEB)

    Cognet, G

    1998-07-07

    In nuclear reactors, whatever the type considered, Pressurized Water Water Reactors (PWRs), Fast Breeder reactors (FBRs)..., thermal-hydraulics, the science of fluid mechanics and thermal behaviour, plays an essential role, both in nominal operating and accidental conditions. Fluid can either be the primary fluid (liquid or gas) or a very specific fluid called corium, which, in case of severe accident, could result from core and environning structure melting. The work reported here represents a 20-year contribution to thermal-hydraulic issues which could occur in FBRs and PWRs. Working on these two types of reactors, both in nominal and severe accident situations, has allowed me to compare the problems and to realize the importance of communication between research teams. The evolution in the complexity of studied problems, unavoidable in order to reduce costs and significantly improve safety, has led me from numerical modelling of single-phase flow turbulence to high temperature real melt experiments. The difficulties encountered in understanding the observed phenomena and in increasing experimental databases for computer code qualification have often entailed my participation in specific measurement device developments or adaptations, in particular non-intrusive devices generally based on optical techniques. Being concerned about the end-use of this research work, I actively participated in `in-situ` thermalhydraulic experiments in the FBRs: Phenix and Super-Phenix, of which I appreciated their undeniable scientific contribution. In my opinion, the thermal-hydraulic questions related to severe accidents are the most complex as they are at the cross-roads of several scientific specialities. Consequently, they require a multi-disciplinary approach and a continuous see-saw motion between experimentalists and modelling teams. After a brief description of the various problems encountered, the main ones are reported. Finally, the importance for research teams to

  4. The nuclear refugees; Les refugies du nucleaire

    Energy Technology Data Exchange (ETDEWEB)

    Linton, M.

    2011-06-15

    The authors propose a report on the various situations of people who had to be evacuated after the Fukushima accident. Along with examples of people who left their homes with taking with them a single object, the authors describe and comment how this evacuation occurred, the problems faced by the authorities for refugee reception and accommodation. This evacuation has been either organised or spontaneous. Hospitals had to be evacuated as well. Then, local authorities faced food shortage. Some animals have been saved, other starved to death. Dead animals are covered with lime. Dead bodies are decontaminated before being given back to families. Tests are regularly performed to assess people contamination. A second article discussed the bad news concerning the different Fukushima reactors with their melted cores. The geophysical aspects of the earthquake are evoked in a last article

  5. Is it possible to recycle nuclear wastes? Costs, risks and stakes of the plutonium industry; Peut-on recycler les dechets nucleaires? Couts, risques et enjeux de l'industrie du plutonium

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2009-07-01

    This document, published by the French association 'Sortir du nucleaire' (Get out of nuclear), gives some information on the chain reaction from uranium to plutonium, the difference between reprocessing (which does not reduce waste volumes but multiply waste types) and recycling, the high risks associated with plutonium transport, La Hague as the most dangerous nuclear site in France, reprocessing as the alibi for the French nuclear industry, Areva as an expert in propaganda, reprocessing as an absurd world strategy, plutonium as a fuel for proliferation, the myth of unlimited energy with the breeder reactors, and so on

  6. Evaluation of a Consistent LES/PDF Method Using a Series of Experimental Spray Flames

    Science.gov (United States)

    Heye, Colin; Raman, Venkat

    2012-11-01

    A consistent method for the evolution of the joint-scalar probability density function (PDF) transport equation is proposed for application to large eddy simulation (LES) of turbulent reacting flows containing evaporating spray droplets. PDF transport equations provide the benefit of including the chemical source term in closed form, however, additional terms describing LES subfilter mixing must be modeled. The recent availability of detailed experimental measurements provide model validation data for a wide range of evaporation rates and combustion regimes, as is well-known to occur in spray flames. In this work, the experimental data will used to investigate the impact of droplet mass loading and evaporation rates on the subfilter scalar PDF shape in comparison with conventional flamelet models. In addition, existing model term closures in the PDF transport equations are evaluated with a focus on their validity in the presence of regime changes.

  7. Advanced Supersonic Nozzle Concepts: Experimental Flow Visualization Results Paired With LES

    Science.gov (United States)

    Berry, Matthew; Magstadt, Andrew; Stack, Cory; Gaitonde, Datta; Glauser, Mark; Syracuse University Team; The Ohio State University Team

    2015-11-01

    Advanced supersonic nozzle concepts are currently under investigation, utilizing multiple bypass streams and airframe integration to bolster performance and efficiency. This work focuses on the parametric study of a supersonic, multi-stream jet with aft deck. The single plane of symmetry, rectangular nozzle, displays very complex and unique flow characteristics. Flow visualization techniques in the form of PIV and schlieren capture flow features at various deck lengths and Mach numbers. LES is compared to the experimental results to both validate the computational model and identify limitations of the simulation. By comparing experimental results to LES, this study will help create a foundation of knowledge for advanced nozzle designs in future aircraft. SBIR Phase II with Spectral Energies, LLC under direction of Barry Kiel.

  8. 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)

  9. The First Two Years of Operating Experience of the Kahl Nuclear Power Station; Experience acquise pendant les deux premieres annees de fonctionnement de la centrale nucleaire de Kahl; Opyt pervykh dvukh let ehkspluatatsii atomnoj ehlektrostantsii v Kale; Experiencia adquirida en los primeros cuatro anos de funcionamiento de la central nucleoelectrica de Kahl

    Energy Technology Data Exchange (ETDEWEB)

    Bruchner, H. J. [Aeg-Kernenergieanlagen, Frankfurt-am-Main (Germany); Weckesser, A. [Versuchs-Atomkraftwerk Kahl Gmbh, Kahl (Germany)

    1963-10-15

    , une boucle experimentale destinee a l'etude de la surchauffe nucleaire. (author) [Spanish] La central de Kahl constituye la primera central nucleoelectrica europea de propiedad privada, y funciona en carga desde junio de 1961. Esta equipada con un reactor de agua hi que trabaja en ciclo indirecto por circulacion natural. Su capacidad electrica neta asciende a 15 MW y hasta febrero de 1963 habia producido 140 millones de kWh. La memoria revisara la experiencia adquirida durante su funcionamiento, ante todo con el extenso programa de ensayos sobre el comportamiento transitorio y la exploracion gamma. Presentara datos acerca del resultado que han dado en funcionamiento ciertas partes de la central, tales como el dispositivo de accionamiento de las barras de control, el sistema de purificacion de los gases de escape y la turbina. Una vez terminado el programa de ensayos, la planta se exploto en carga basica durante algun tiempo a fin de reunir datos sobre el rendimiento del combustible en la ptactica. Una vez completada esta fase, se instalara en el reactor de Kahl un circuito experimental de sobrecalentamiento nuclear. (author) [Russian] Atomnaya ehlektrostantsiya v Kale, pervaya v Evrope chastnaya atomnaya ehlektrostantsiya, ehkspluatiruetsya pod nagruzkoj s iyunya 1961 goda. Na ehlektrostantsii ustanovlen reaktor s kipyashchej vodoj, kosvennym tsiklom i estestvennoj tsirkulyatsiej. Chistaya ehlektricheskaya moshchnost' reaktora sostavlyaet 15 mgvt. Do fevralya 1963 goda kolichestvo poluchennoj ehnergii sostavilo 140 mln. kvt.ch. Rassmotren opyt ehkspluatatsii, v chastnosti rasshirennaya programma ispytanij: naprimer,povedenie reaktora pri perekhodnom protsesse i kontrol' gamma-izlucheniya. Budut predstavleny rezul'taty izucheniya ehkspluatatsionnoj kharakteristiki nekotorykh komponentov ustanovki, naprimer sistemy privoda reguliruptsikh sterzhnej, sistemy udaleniya gaza i turbiny. Posle osushchestvleniya ehtoj programmy ispytanij ustanovka v techenie nekotorogo vremeni

  10. 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

  11. LES Modeling with Experimental Validation of a Compound Channel having Converging Floodplain

    Science.gov (United States)

    Mohanta, Abinash; Patra, K. C.

    2018-04-01

    Computational fluid dynamics (CFD) is often used to predict flow structures in developing areas of a flow field for the determination of velocity field, pressure, shear stresses, effect of turbulence and others. A two phase three-dimensional CFD model along with the large eddy simulation (LES) model is used to solve the turbulence equation. This study aims to validate CFD simulations of free surface flow or open channel flow by using volume of fluid method by comparing the data observed in hydraulics laboratory of the National Institute of Technology, Rourkela. The finite volume method with a dynamic sub grid scale was carried out for a constant aspect ratio and convergence condition. The results show that the secondary flow and centrifugal force influence flow pattern and show good agreement with experimental data. Within this paper over-bank flows have been numerically simulated using LES in order to predict accurate open channel flow behavior. The LES results are shown to accurately predict the flow features, specifically the distribution of secondary circulations both for in-bank channels as well as over-bank channels at varying depth and width ratios in symmetrically converging flood plain compound sections.

  12. The Pegase reactor loops; Les boucles du reacteur Pegase

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1968-07-01

    After 4 years operation, experimentation and maintenance of the gas loops built especially for the nuclear fuel testing reactor Pegase, it appears desirable not only to gather together in a single document the essential characteristics and particularities of these devices and of their associated equipment, but also to give the reasons for the technical modifications and the way in which they were carried out; this is done here by the persons themselves who were responsible, day after day, for operating these loops. This essentially practically experience thus complements the careful research and preliminary testing carried out on these loops or on their prototypes. It should be of interest to those who deal with problems concerned with the design or operation of irradiation loops in experimental reactors or of similar equipment. (authors) [French] Apres 4 annees de fonctionnement, d'experimentation et d'entretien sur les boucles a gaz, construites specialement pour le reacteur d'essai des combustibles nucleaires Pegase, il a paru souhaitable non seulement de rassembler dans un meme document les caracteristiques et les particularites essentielles de ces dispositifs et des appareillages qui leur sont associes, mais aussi d'y preciser les raisons et les modalites des mises au point techniques, apportees par ceux qui, jour apres jour pendant cette periode, ont eu la charge de mettre en oeuvre ces boucles. Cette experience essentiellement pratique complete donc les etudes minutieuses et les essais preliminaires de ces boucles ou de leurs prototypes. Elle doit etre de quelque interet pour ceux qui sont confrontes aux problemes de conception ou d'exploitation de boucles d'irradiation dans des reacteurs experimentaux ou des dispositifs analogues. (auteurs)

  13. Contribution to the study of several chemical hazards in the Centre d'Etudes Nucleaires of Fontenay-aux-Roses; Contribution a l'etude de quelques nuisances chimiques au centre d'etudes nucleaires de Fontenay-aux-Roses

    Energy Technology Data Exchange (ETDEWEB)

    Megemont, C; Grau, C [Commissariat a l' Energie Atomique, Fontenay-aux-Roses (France). Centre d' Etudes Nucleaires

    1968-10-01

    From the checking of 2750 index cards of hazards, the study relates the distribution of the chemical hazards in the Centre d'Etudes Nucleaires of Fontenay-aux-Roses. Those concerning the greatest number of agents in the Centre are classified according to the categories corresponding to the different conditions of working. Thus, the most important are put forward. Then, the authors rapidly make a review of hazards which may have some special interest because they appear more specific of the nuclear energy or because they are the most frequently noted on the index cards of hazards. The case of the tributylphosphate is studied more precisely. (authors) [French] A partir de l'examen de 2750 fiches de nuisances, l'etude porte sur la repartition des nuisances chimiques au Centre d'Etudes Nucleaires de Fontenay-aux-Roses. Celles qui concernent le plus grand nombre d'agents du Centre sont classees selon les categories correspondant aux differentes conditions de travail. Les plus importantes d'entre elles sont ainsi mises en evidence. | Les auteurs passent ensuite en revue, rapidement, les nuisances qui peuvent presenter un interet particulier soit parce qu'elles semblent plus specifiques de l'Energie Nucleaire, soit parce qu'on les rencontre le plus frequemment sur les fiches de nuisances. Le cas du tributylphosphate est envisage de facon plus detaillee. (auteurs)

  14. Relationship between the nuclear resonance of cobalt metal and its ferromagnetic properties; Relations entre la resonance nucleaire du cobalt metallique et ses proprietes ferromagnetiques

    Energy Technology Data Exchange (ETDEWEB)

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

    1964-05-15

    Theoretical study of nuclear magnetic resonance in ferromagnetic metals shows the near dependence of ferromagnetic properties and unusual feature of this nuclear resonance. This results from a strong interaction between nuclei and magnetic electrons. They excite the nuclei, and, in Bloch walls, submit them to a RF field much stronger than those directly applied. The parameters of the resonance are determined from wall movement and depend consequently of ferromagnetic constants. The theory is enable to provide quantitatively some peculiar effects, specially those of a continuous magnetic field and of temperature. Experimental study was made on cobalt powders, and is in good agreement with theory. However one must take the skin-effect into consideration and accordingly adjust, the theory. This can explain some observed divergences, as well as the influence at particles size and magnetic field over the line shape. Original informations have been obtained about some typical ferromagnetic properties of cobalt, when studying magnetic field effect, and it has been able to apply this method to other ferromagnetic materials. In consideration of the peculiar characteristics of this nuclear resonance, which occurs without external magnetic field and whose line width is large, new models of spectrographs have been realized and have permitted accurate measures of the line shape. The weak intensity of the signals obtained in some cases, has induced the elaboration of an original method of extraction whose theory and practical uses are described here. The whole of this experiment reveals the nuclear resonance as a strong way for the study of ferromagnetism, which is able to detect microscopic phenomenons, not easily accessible by classical methods. (author) [French] L'etude theorique de la resonance magnetique nucleaire dans les metaux ferromagnetiques revele l'etroite liaison entre les proprietes ferromagnetiques et l'aspect inhabituel de cette resonance. Ceci

  15. Relationship between the nuclear resonance of cobalt metal and its ferromagnetic properties; Relations entre la resonance nucleaire du cobalt metallique et ses proprietes ferromagnetiques

    Energy Technology Data Exchange (ETDEWEB)

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

    1964-05-15

    Theoretical study of nuclear magnetic resonance in ferromagnetic metals shows the near dependence of ferromagnetic properties and unusual feature of this nuclear resonance. This results from a strong interaction between nuclei and magnetic electrons. They excite the nuclei, and, in Bloch walls, submit them to a RF field much stronger than those directly applied. The parameters of the resonance are determined from wall movement and depend consequently of ferromagnetic constants. The theory is enable to provide quantitatively some peculiar effects, specially those of a continuous magnetic field and of temperature. Experimental study was made on cobalt powders, and is in good agreement with theory. However one must take the skin-effect into consideration and accordingly adjust, the theory. This can explain some observed divergences, as well as the influence at particles size and magnetic field over the line shape. Original informations have been obtained about some typical ferromagnetic properties of cobalt, when studying magnetic field effect, and it has been able to apply this method to other ferromagnetic materials. In consideration of the peculiar characteristics of this nuclear resonance, which occurs without external magnetic field and whose line width is large, new models of spectrographs have been realized and have permitted accurate measures of the line shape. The weak intensity of the signals obtained in some cases, has induced the elaboration of an original method of extraction whose theory and practical uses are described here. The whole of this experiment reveals the nuclear resonance as a strong way for the study of ferromagnetism, which is able to detect microscopic phenomenons, not easily accessible by classical methods. (author) [French] L'etude theorique de la resonance magnetique nucleaire dans les metaux ferromagnetiques revele l'etroite liaison entre les proprietes ferromagnetiques et l'aspect inhabituel de cette resonance. Ceci resulte du

  16. Problems related with the power regulation of reactors by physico-chemical methods, and the behaviour of water and heavy water in nuclear reactors; Comportement de l'eau et de l'eau lourde dans les reacteurs nucleaires et problemes de la regulation de puissance par voie physico-chimique

    Energy Technology Data Exchange (ETDEWEB)

    Dolle, L; Conan, D; Dirian, G [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1964-07-01

    Experience of the CEA heavy water reactors and a systematic study of the radiolytic decomposition of water in the core of swimming-pool reactors are described. Setting up of reactivity control by physico-chemical methods. Reactivity control by homogeneous poisoning of the reactor A comparison of the evolution of xenon poisoning with the residual anti reactivity of the poison in solution during its nuclear consumption establishes the programme which must govern the variation in its concentration if the exact compensation is to be produced The behaviour of the poison towards the reactor materials under the particular operational conditions must be taken into account. Radiolytic decomposition of water in the reactors in the presence of soluble poisons: A study of the effect of certain chemically inert salts, present in small concentrations in the water, on its radiolytic decomposition rate, has led to some new results which are discussed. The choice of a soluble poison is justified on the basis of the above results. Reactivity control by the use of a gaseous absorbent The use of a gas control rod circuit for compensation purposes, in place of solid control rods is described. The use of soluble poisons in the moderator to compensate the xenon effect, and of a gaseous absorbent in a circuit known as a gas control rod form original aspects of the reactivity control in the reactor EL 4. (authors) [French] L'observation du comportement de l'eau et de l'eau lourde dans les reacteurs en exploitation, contribue au fonctionnement sur de ceux-ci et oriente certaines etudes relatives aux techniques de controle de la reactivite par mise en oeuvre de poisons solubles. L'utilisation de poisons nucleaires dissous dans l'eau du reacteur entraine une pollution chimique de celle-ci. Les conditions d'emploi permettant d'eviter les effets indesirables de cette pollution sont etudiees. Les problemes analytiques - bien qu'importants - ne sont pas abordes dans le cadre de la communication

  17. Spectral content of seismic movements produced by underground nuclear explosions; Contenu spectral des mouvements seismiques dus aux explosions nucleaires souterraines

    Energy Technology Data Exchange (ETDEWEB)

    Albaret, A; Duclaux, F [Commissariat a l' Energie Atomique, Bruyeres-le-Chatel (France). Centre d' Etudes

    1969-07-01

    After a summary of available data, both theoretical and experimental, concerning the spectral content of seismic movements, a description is given of the experiments carried out during the French nuclear explosions in the Sahara, and of the results obtained on the volume waves. A comparison is then made with certain American results. A new method is described for studying the amplitude spectra; it has made it possible to show that the amount of low frequencies in the spectrum increases with the power of the explosion, and decreases with the distance to the zero point and with the filtering effect of the weathered zone. A calculation is then made of the low cut-off ground filter, this giving a better representation of the initial seismic phenomenon. (authors) [French] Apres avoir resume les connaissances disponibles, aussi bien theoriques qu'experimentales, sur le contenu spectral des mouvements seismiques, on decrit les experiences effectuees a l'occasion des explosions nucleaires francaises du Sahara et les resultats obtenus sur les ondes de volume. Puis on les compare avec certains resultats americains. On decrit une nouvelle methode d'etude des spectres d'amplitudes qui montre que le spectre est d'autant plus riche en basses frequences que la puissance de l'explosion est grande, que la distance au point zero est faible et qu'il est moins filtre par la zone alteree superficielle. Puis on calcule le filtre terrain coupe-bas qui permet de donner une representation plus fidele du phenomene seismique initial. (auteurs)

  18. Acute pulmonary injury induced by experimental muscle trauma Lesão pulmonar aguda induzida por trauma muscular experimental

    Directory of Open Access Journals (Sweden)

    Márcia Andréa da Silva Carvalho Sombra

    2011-01-01

    Full Text Available PURPOSE: To develop an easily reproducible model of acute lung injury due to experimental muscle trauma in healthy rats. METHODS: Eighteen adult Wistar rats were randomized in 3 groups (n=6: G-1- control, G-2 - saline+trauma and G-3 - dexamethasone+trauma. Groups G-1 and G-2 were treated with saline 2,0ml i.p; G-3 rats were treated with dexamethasone (DE (2 mg/kg body weight i.p.. Saline and DE were applied 2h before trauma and 12h later. Trauma was induced in G-2 and G-3 anesthetized (tribromoethanol 97% 100 ml/kg i.p. rats by sharp section of anterior thigh muscles just above the knee, preserving major vessels and nerves. Tissue samples (lung were collected for myeloperoxidase (MPO assay and histopathological evaluation. RESULTS: Twenty-four hours after muscle injury there was a significant increase in lung neutrophil infiltration, myeloperoxidase activity and edema, all reversed by dexamethasone in G-3. CONCLUSION: Trauma by severance of thigh muscles in healthy rats is a simple and efficient model to induce distant lung lesions.OBJETIVO: Desenvolver um modelo facilmente reprodutível de lesão pulmonar aguda decorrente de trauma muscular experimental em ratos sadios. MÉTODOS: Dezoito ratos Wistar adultos foram randomizados em 3 grupos (n=6: G-1-controle, G-2 - trauma+salina e G-3 - trauma+dexametasona. Grupos G-1 e G-2 foram tratados com salina 2,0 ml ip, G-3 ratos foram tratados com dexametasona (DE (2 mg/kg peso corporal ip. Salina e DE foram aplicadas 2h antes e 12h depois do trauma. Trauma foi induzido em ratos G-2 e G-3 anestesiados (tribromoetanol 97% de 100 ml/kg, i.p. por secção da musculatura anterior da coxa logo acima da articulação do joelho, preservando os grandes vasos e nervos. Amostras de tecido (pulmão foram coletadas para avaliação da mieloperoxidase (MPO, e exames histopatológicos. RESULTADOS: Vinte e quatro horas após a indução da lesão muscular houve um aumento significativo na infiltração de neutr

  19. New features of nuclear excitation by {alpha} particles scattering; Nouveaux aspects de l'excitation nucleaire par diffusion de particules {alpha}

    Energy Technology Data Exchange (ETDEWEB)

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

    1962-07-01

    Inelastic scattering of medium energy a particles by nuclei is known to excite preferentially levels of collective character. We have studied the scattering of isotopically enriched targets of Ca, Fe, Ni, Cu, Zn. In part I, we discuss the theoretical features of the interaction. In part II, we describe the experimental procedure. Results are presented and analysed in part III. {alpha} particles scattering by Ca{sup 40} is showed to excite preferentially odd parity levels. In odd nuclei we have observed multiplets due to the coupling of the odd nucleon with the even-even core vibrations. For even-even nuclei, a few levels are excited with lower cross-sections between the well-known first 2{sup +} and 3{sup -} states. Some could be members of the two phonon quadrupole excitation and involve a double nuclear excitation process. (author) [French] On sait que la diffusion inelastique des particules alpha de moyenne energie excite preferentiellement des niveaux de caractere collectif. Nous avons etudie la diffusion des particules alpha de 44 MeV du cyclotron de Saclay par des isotopes separes de Ca, Fe, Ni, Cu, Zn. Dans la premiere partie nous exposons les theories de cette interaction. Dans la seconde nous decrivons le systeme experimental. Les resultats sont donnes dans la troisieme partie. Nous montrons que les niveaux excites preferentiellement pour {sup 40}Ca par diffusion ({alpha},{alpha}') sont de parite negative. Dans les noyaux pair-impair nous avons observe des multiplets dus au couplage du nucleon celibataire avec les vibrations du coeur pair-pair. Pour les noyaux pair-pair nous avons pu etudier entre le premier niveau 2{sup +} et le niveau 3{sup -} deja bien connus certains etats plus faiblement excites. Il semble qu'ils sont dus a une excitation quadrupolaire a deux phonons et impliquent un processus de double excitation nucleaire. (auteur)

  20. Technique of nuclear reactors controls; Technique des controles des reacteurs nucleaires

    Energy Technology Data Exchange (ETDEWEB)

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

    1953-12-15

    This report deal about 'Techniques of control of the nuclear reactors' in the goal to achieve the control of natural uranium reactors and especially the one of Saclay. This work is mainly about the measurement into nuclear parameters and go further in the measurement of thermodynamic variables,etc... putting in relief the new features required on behalf of the detectors because of their use in the thermal neutrons flux. In the domain of nuclear measurement, we indicate the realizations and the results obtained with thermal neutron detectors and for the measurement of ionizations currents. We also treat the technical problem of the start-up of a reactor and of the reactivity measurement. We give the necessary details for the comprehension of all essential diagrams and plans put on, in particular, for the reactor of Saclay. (author) [French] Nous avons aborde le probleme de la ''Technique du Controle des reacteurs nucleaires'' dans le but de realiser le controle du reacteur de Saclay. C'est ainsi que nous avons ete amene a etudier le probleme dans son ensemble, tel qu'il se pose pour tout reacteur a uranium naturel. Ce travail traite principalement du domaine des mesures a caractere nucleaire et s'etend dans le domaine des mesures thermodynamque de niveaux, etc... mettant en relief les caracteristiques nouvelles exigees de la part des detecteurs du fait de leur utilisation dans le flux de neutrons thermiques. Dans le domaine de mesures nucleaires, nous indiquons principalement les realisations et les resultats obtenus pour les detecteurs de neutrons thermiques et pour la mesure de courants d'ionisations. Nous traitons egalement du probleme technique du demarrage d'un reacteur et du probleme de la mesure de la reactivite. Nous donnons les details necessaires a la comrehension de tous les schemas et plans de cablages essentiels mis au point, en particulier, pour le reacteur de Saclay. (auteur)

  1. The Text of the Agreement between Belgium, Denmark, the Federal Republic of Germany, Ireland, Italy, Luxembourg, The Netherlands, the European Atomic Energy Community and the Agency in Connection with the Treaty on the Non-Proliferation of Nuclear Weapons; Texte de l'Accord entre la Belgique, le Danemark, la Republique Federale d' Allemagne, l'Irlande, l'Italie, le Luxembourg, les Pays-Bas, la Communaute Europeenne de l'En-Ergie Atomique et L'Agence En Application Du Traite Sur La Non-Proliferation Des Armes Nucleaires

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1973-09-14

    The text of the Agreement, and of the Protocol thereto, between Belgium, Denmark, the Federal Republic of Germany, Ireland, Italy, Luxembourg, The Netherlands, the European Atomic Energy Community and the Agency in implementation of Article III (1) and (4) of the Treaty on the Non-Proliferation of Nuclear Weapons (reproduced in document INFCIRC/140) is reproduced in this document for the information of all Members [French] Le texte de l'Accord, ainsi que celui du Protocole qui y est joint, entre la Belgique, le Danemark, la Republique fdrale d'Allemae, l'Irlande, l'Italie, le Luxembourg, les Pays-Bas, la Communaute europenne de l'energie atomique et l'Agence condu en application des paragraphes 1 et 4 de l'article III du Traite sur la non proliferation des armes nucleaires sont reproduits dans le present document pour l'information de tous les Membres.

  2. A sepse como causa de lesão renal aguda: modelo experimental

    Directory of Open Access Journals (Sweden)

    Carolina Ferreira Pinto

    2012-10-01

    Full Text Available A sepse associada à falência de múltiplos órgãos como a lesão renal aguda (LRA demonstra alta taxa de mortalidade no paciente crítico. Este estudo investigou a LRA induzida pela sepse em modelo experimental. Foram utilizados ratos da raça Wistar, adultos e machos divididos nos seguintes grupos: Controle - controle cirúrgico e Sepse - indução da sepse pela ligadura e punção do cécon (LPC. Foram avaliados os parâmetros fisiológicos (temperatura retal, pressão arterial média - PAM, glicemia sérica e fluxo urinário; a função renal (clearance de creatinina; o estresse oxidativo (peróxidos urinários e substâncias reativas com ácido tiobarbitúrico - TBARS e realizada a análise histológica renal. O estudo conclui que a LRA induzida pela sepse caracteriza-se por lesão endotelial com disfunção hemodinâmica, liberação de mediadores inflamatórios e geração de espécies reativas de oxigênio (EROs por células tubulares, caracterizando-se como uma associação de vasoconstrição renal de origem hemodinâmica e inflamatória.

  3. Nuclear techniques in food and agriculture and international cooperation in their use; Les sciences nucleaires dans l'alimentation et l'agriculture et la cooperation internationale dans ce domaine

    Energy Technology Data Exchange (ETDEWEB)

    Fried, M.; Sigurbjörnsson, B. [Joint FAO/IAEA Division of Atomic Energy in Food and Agriculture, International Atomic Energy Agency, Vienna (Austria)

    1970-01-15

    that the medfly attacking citrus, the olive fly, the codling moth attacking apples, the tsetse fly and a number of other insects can be eliminated in this way. Radiation can be used to attenuate parasitic larvae attacking animals. The parasites which have thus lost their virulence are used in the production of animal vaccines. In fact, this is still the only known method of producing such vaccines. Isotopic tracers are used to study the movement and metabolism of nutrients in animal production and are particularly useful in studies of essential micronutrients. This unique ability of isotopic tracers to enable detection of chemicals in minute quantities forms the basis for a new program on studies of harmful pesticide residues on plant and animal foods. The sterilizing and killing effect of radiation has been shown to be uniquely effective in preventing or delaying spoilage in a variety of food commodities. Radiation preservation can, for example, be applied to perishable products which do not tolerate cooking or freezing - even after the products are packed. To foster international activities in the field of nuclear science in food and agriculture, the Joint FAO/IAEA Division of Atomic Energy in Food and Agriculture carries out a single joint program of work approved by the two parent organizations. To carry out work in all these fields, the Division relies heavily on the concept of coordinated research based on research contracts or research agreements. A large part of the work is carried out under various technical assistance projects including expert advice, equipment and training and through the two UNDP Special Fund Projects executed by the IAEA. The IAEA Laboratory plays an indispensable role in the Division’s programs by providing various coordinating services, research, and specialized training. (author) [French] Les méthodes nucléaires sont employées dans la recherche et la production à tous les niveaux successifs de la chaîhe alimentaire: sol et eau

  4. Determination of the cross-sections of some nuclear reactions occurring as a result of cosmic radiation (1963); Determination des sections efficaces de quelques reactions nucleaires intervenant dans les effets ou rayonnement cosmique (1963)

    Energy Technology Data Exchange (ETDEWEB)

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

    1962-06-15

    The high energy reactions studied during this research are reactions liable to occur as a result of cosmic radiation. On the one hand the reaction {sup 16}O(p, 3p){sup 14}C was studied and its cross-section measured between 65 MeV and 2.7 GeV; a value of 2.3 mb {+-} 0.5 was found. These values have mode it possible to forecast measurable quantities of carbon-14 in meteorites and also to measure them. On the other hand the reactions {sup 12}C({sup 16}O...), {sup 12}C({sup 14}N...) and {sup 12}C({sup 12}C...) have been studied and an attempt has been made to explain the mechanism of these reactions. (author) [French] Les reactions a hautes energies qui ont ete etudiees au court de ce travail sont des reactions susceptibles de se produire sous l'effet du rayonnement cosmique. Il s'agit d'une part de la reaction {sup 16}O(p, 3p){sup 14}C dont on a mesure la section efficoce egale a 2,3 mb {+-} 0,5 entre 65 MeV et 2,7 GeV. Ces valeurs ont permis de prevoir des quantites mesurables de carbone 14 dans les meteorites et par suite de les determiner. D'autre part les reaction {sup 12}C({sup 16}O...), {sup 12}C({sup 14}N...) et {sup 12}C({sup 12}C...) ont ete etudiees et on a tente d'expliquer le mecanisme de ces reactions. (auteur)

  5. Nuclear explosion and internal contamination; Explosion nucleaire et contamination interne

    Energy Technology Data Exchange (ETDEWEB)

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

    1956-07-01

    By the study of the conditions of internal contamination due to the radioactive mixture produced by a nuclear explosion, the parts played by the relative weights of the different elements and the mode of expression of the doses are considered. Only the knowledge of the weight composition of the contamination mixture and of its evolution as a function of time can provide the required basis for the study of its metabolism in the organism. The curves which give the composition of the fission product mixture - in number of nuclei - - as a function of time - have been established. These curves are applied to some practical examples, particularly relative to the nature of contamination, radiotoxicity of some elements and assessment of hazards. (author) [French] Etudiant les modalites de la contamination interne par les elements radioactifs apparus lors d'une explosion nucleaire, le role de la 'masse' et le mode d'expression des doses sont envisages. La connaissance de la composition en 'masse' du melange contaminant et de son evolution en fonction du temps peut seule apporter les bases necessaires a l'etude de son comportement dans l'organisme. Les courbes donnant la composition du melange de produits de fission - en nombre de noyaux - - en fonction du temps - ont ete etablies. Quelques applications pratiques, relatives en particulier a la nature de la contamination, a la radiotoxicite de certains elements et a l'evaluation de risque, sont envisagees a titre d'exemple. (auteur)

  6. Contribution to the study of the fission-gas release in metallic nuclear fuels; Contribution a l'etude du degagement des gaz de fission dans les combustibles nucleaires metalliques

    Energy Technology Data Exchange (ETDEWEB)

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

    1969-10-01

    In order to study the effect of an external pressure on the limitation of swelling due to fission-gas precipitation, some irradiations have been carried out at burn-ups of about 35.000 MWd/ton, and at average sample temperatures of 575 Celsius degrees, of non-alloyed uranium and uranium 8 per cent molybdenum gained in a thick stainless steel can. A cylindrical central hole allows a fuel swelling from 20 to 33 per cent according to the experiment. After irradiation, the uranium samples showed two types of can rupture: one is due to the fuel swelling, and the other, to the pressure of the fission gases, released through a network of microcracks. The cans of the uranium-molybdenum samples are all undamaged and it is shown that the gas release occurs by interconnection of the bubbles for swelling values higher than those obtained in the case of uranium. For each type of fuel, a swelling-fission gas release relationship is established. The results suggest that good performances with a metallic fuel intended for use in fast reactor conditions can be obtained. (author) [French] Afin d'etudier l'effet d'une pression exterieure sur la limitation du gonflement due a la precipitation des gaz de fission, on a irradie a des taux de combustion d'environ 35.000 MWj/t et a des temperatures moyennes de 575 degres des echantillons d'uranium non allie et d'uranium-molybdene 8 pour cent contenus dans une gaine en acier inoxydable epaisse. Un trou cylindrique central permet au combustible de gonfler librement de 20 a 33 pour cent suivant les cas. Apres irradiation les echantillons d'uranium presentent deux types de ruptures de gaine: l'une due au gonflement du combustible, l'autre a la pression des gaz degages, ce degagement des gaz etant provoque par un reseau de micro-fissures. Les gaines des echantillons d'alliage uranium-molybdene sont toutes intactes et l'on montre que le relachement des gaz opere par interconnexion des bulles pour des valeurs de gonflement plus elevees que dans

  7. Multiphase Reactors: Models and Experimental Verification Les réacteurs polyphasés : modèles et vérification expérimentale

    Directory of Open Access Journals (Sweden)

    Dudukovic M. P.

    2006-11-01

    implementation of a convection dispersion model. The planned implementation of fan-beam tomography would quantify the two-dimensional holdup distribution and together with CARPT provide all the data necessary for verification of fundamental two phase flow models. Pressure drop, holdup, flow regime transition and phase distribution in trickle-beds has received considerable attention but no generally accepted theory for prediction of these quantities exists. Here we describe a phenomenological model for the low interaction regime which views the bed as an array of slits with liquid film flow. Universal velocity profile is used to describe the flow in both liquid films and the gas core and a large data bank for pressure drop and holdup was used to confirm that in the low interaction regime each of the two phases ignores the presence of the other one. The final model contains only two parameters, which are determined from single phase flow experiments, and contains no constants fitted to two phase flow data. The model predicts pressure drop and holdup in the uniform low interaction regime better than any of the existing models. Furthermore, introducing the Kapitza's criterion for laminar liquid film instability into the model the flow regime transition to pulsing is predicted well for all the data that satisfy the conditions for the theory to apply. Other pore level transition mechanisms are suspected for other data. The above phenomenological model is also used as a basis for predicting liquid distribution in a cell model of a trickle-bed. Experimental confirmation awaits the application of PET technology. L'identification et la quantification des régimes, des distributions des rétentions de phase, des schémas de flux et du mélange en retour sont d'une importance primordiale pour extrapoler à l'échelle et concevoir correctement les réacteurs polyphasés. Les modèles existants sont, malheureusement, bien souvent étayés par des résultats expérimentaux inadéquats. Nous d

  8. IPSN's experimental programmes on fires; Les recherches experimentales de l'IPSN sur les feux

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-07-06

    Every year fires occur in nuclear installations as they do in any industrial facility. They feed on cables, electrical equipment cabinets, oils, solvents..., they might lead to the degradation of the safety standard of the installation or they might threaten the confinement of radioactive materials. In this document IPSN presents its experimental programmes and its facilities in Saclay and Cadarache designed to study the triggering and the propagation of fires and flames in closed and ventilated premises. (A.C.)

  9. The formation of scientists and technicians at the 'Centre d'Etudes Nucleaires' at Saclay; Formation des scientifiques et des techniciens au Centre d'Etudes Nucleaires de Saclay

    Energy Technology Data Exchange (ETDEWEB)

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

    1958-07-01

    The considerable needs in research workers and scientists which are asked by the nuclear energy obliged the Commissariat a l'Energie atomique to deal with a particular effort to increase the quantitative and qualitative formation of scientists. Most various ways have been used. 1- A National Institute of Nuclear Sciences and Nuclear Techniques was created, by a joint decree of the Prime Minister and the Minister for National Education (june 18, 1957). This Institute of Higher Teaching (250 students) indulges in the following matters: atomic engineering, quantum mechanics, theory and technic of particle accelerators, special metallurgy, radiobiology, thermic and mechanics of fluids. 2- An associated centre of the 'Conservatoire National des Arts et Metiers' waeated (200 students) for technical assistants, drawers, etc. 3- In contribution with both electronic industry and Ministry of Work, the Centre d'Etudes Nucleaires contributes to an accelerated formation of technical assistants into Professional Centres. Conclusion: Training of scientists and research workers is one of the most important activities of the Centre d'Etudes Nucleaires de Saclay. Without losing its technical efficiency, it has supplied and varied means adapted to the various purposes that we shall reach. (author)Fren. [French] Les besoins considerables actuels et previsibles en chercheurs et scientifiques necessites par l'avevement de l'energie nucleaire imposaient au Commissariat a I'Energie atomique un effort particulier pour augmenter la formation quantitative et qualitative des scientifiques. Les moyens les plus divers ont ete mis en oeuvre: 1- Creation de l'Institut National des Sciences et Techniques Nucleaires par decret de la Presidence du Conseil et de l'Education Nationale en date du 18.6.57. Cet Institut d'Enseignement Superieur (250 etudiants) donne des cours en: genie atomique, mecanique quantique, theorie et technique des Accelerateurs de particules, metallurgie speciale, radiobiologie

  10. Resonance quadripolaire nucleaire dans les halogenures d'actinides, ThBr 4, ThCl 4 ET UCl 4. II. Polymorphisme et transition de phase du premier ordre dans ThBr 4. Resonance du Brome dans UBr 4.

    Science.gov (United States)

    Gourdji, M.; Péneau, A.; Genet, M.; Guibé, L.

    1983-12-01

    La poursuite de recherches antérieures a permis de caractériser la résonance quadripolaire du brome dans la phase α de ThBr 4 et d'étudier la variation, en fonction de la température, entre 63 et 295 K, de la fréquence de résonance, ν Q(T), correspondante. Une première analyse des conditions expérimentales du passage de la transition α↔β à 426 C a été faite. La résonance du brome dans UBr 4 a également été observée et l'étude en fonction de la température des fréquences de résonance (il y a deux résonances distinctes pour chacun des deux isotopes du brome dans ce composé) a révélé un comportement inattendu en ce sens que les pentes dν Q/dT des courbes ν Q(T) correspondant aux deux résonances sont de signe contraire.

  11. An absolute nuclear magnetic resonance magnetometer; Magnetometre absolu a resonance magnetique nucleaire

    Energy Technology Data Exchange (ETDEWEB)

    Salvi, A [Commisariat a l' Energie Atomique, Grenoble (France). Centre d' Etudes Nucleaires

    1961-10-15

    After an introduction in which the various work undertaken since the discovery of nuclear magnetic resonance is rapidly reviewed, the author describes briefly In the first chapter three types of NMR magnetometers, giving the advantages and disadvantages of each of them and deducing from this the design of the apparatus having the greatest number of qualities Chapter II is devoted to the crossed coil nuclear oscillator which operates continuously over a wide range (800 gamma). To avoid an error due to a carrying over the frequency, the measurement is carried out using bands of 1000 {gamma}. Chapter III deals with frequency measurements. The author describes an original arrangement which makes possible the frequency-field conversion with an accuracy of {+-} 5 x 10{sup -6}, and the differential measurement between two nuclear oscillators. The report finishes with a conclusion and a few recordings. (author) [French] Apres une introduction rappelant les divers travaux effectues en resonance magnetique nucleaire depuis sa mise en evidence, l'auteur decrit sommairement dans le premier chapitre trois types de magnetometre a R.M.N. enumerant les avantages et les inconvenients de chacun a partir desquels il projet, l'appareillage reunissant le maximum de qualites. Le chapitre II est consacre a l'oscillateur nucleaire a bobines croisees permettant un fonctionnement continu dons une large plage (800 gamma). Pour eviter une erreur due a l'entrainement de frequence, la mesure s'effectue par bandes de 1000 {gamma} chacune. Le chapitre III traite la mesure de frequence. L'auteur expose un montage original permettant la traduction frequence-champ avec une precision egale a {+-} 5.10{sup -6}, et la mesure differentielle entre deux oscillateurs nucleaires. Une conclusion et quelques enregistrements terminent ce travail. (auteur)

  12. Pointing Out Main Factors from Design, Construction and Operating Experience of Existing Nuclear Plants for Assisting in Shaping Future Nuclear Power Programmes; Les principaux criteres degages de l'etude, de la construction et de l'exploitation des centrales nucleaires existantes et leur interet pour l'elaboration des futurs programmes d'energie d'origine nucleaire; Ukazanie osnovnykh faktorov proektirovaniya, stroitel'stva i opyta ehkspluatatsii sushchestvuyutsikh atomnykh ehlektrostantsij, chto dolzhno pomoch' pri sostavlenii budushchikh programm atomnoj ehnergetiki; Principales consideraciones relativas al diseno, construccion y explotacion de centrales nucleares, encaminadas a facilitar la preparacion de programas futuros de energia nucleoelectrica

    Energy Technology Data Exchange (ETDEWEB)

    Dalla Volta, F. [Comitato Nazionale per l' Energia Nucleare, Rome (Italy)

    1963-10-15

    enseignements qui ont ete fournis, aux points de vue technique et economique, par l'etude, la construction et l'exploitation des premieres centrales nucleaires, et qui peuvent etre particulierement utiles pour l'implantation de nouvelles centrales de ce genre dans l'avenir, notamment eu egard aux conditions qui regnent en Italie. La technologie actuelle des reacteurs et les progres qu'elle continue de faire revelent une tendance marquee vers la reduction du cout, non seulement des cycles de combustible, mais aussi des elements de la centrale. Cette evolution se trouve d'ailleurs favorisee par la tendance croissante a construire des centrales plus grandes et par le fait que l'etude du developpement du reseau electrique semble indiquer que, sur le plan economique, il y a plus d' avantage ainstaller des centrales nucleaires plus puissantes que d'augmenter la puissance des centrales classiques. Se fondant sur l'experience acquise concernant l'etu de, la construction et l'essai des divers types de centrales existantes, l'auteur donne un apercu des principaux facteurs dont il convient de tenir compte lors de l'etablissement des programmes futurs. Il insiste sur le probleme de l'isolement, vu les incidences favorables que peut avoir sur le choix du site de la centrale la mise au point d'ecrans de protection tres surs, qui puissent etre construits sans augmentation sensible du prix de revient, en tirant notamment parti, pour resoudre certains aspects de ce probleme, des conditions particulieres qui se trouvent reunies en Italie. Quant a l'experience du fonctionnement de certaines centrales d'un modele eprouve, l'auteur examine dans quelle mesure ces installations peuvent etre construites sans difficulte et satisfaire la demande du reseau; il se refere ici egalement au role croissant qu'il est prevu d'attribuer a l'energie d'origine nucleaire en Italie. Enfin, l'auteur souligne a quel point le rassemblement et l'interpretation des donnees relatives aux trois centrales, qui doivent

  13. The use of an experimental device for disposal into the ground at the Centre d'Etudes Nucleaires at Saclay; Utilisation d'un dispositif experimental de rejet dans le sol au C.E.N. de Saclay

    Energy Technology Data Exchange (ETDEWEB)

    Amavis, R; Vaccarezza, J [Commissariat a l' Energie Atomique, Saclay (France).Centre d' Etudes Nucleaires

    1960-07-01

    This report presents the results of the {sup 3}H and {sup 90}Sr percolation tests carried out with Saclay soil, both in the laboratory in the ground itself. The extrapolation using the parameters introduced by Hiester and Vermeulen, as well as by W.J. Kaufman, appear satisfactory when the soil sample is homogeneous. (author) [French] Ce rapport presente les resultats d'essais de percolation de {sup 3}H et de {sup 90}Sr, realises avec le sol de Saclay, en laboratoire et sur le terrain. L'extrapolation utilisant les parametres introduits par Hiester et Vermeulen, ainsi que par W.J. Kaufman, parait satisfaisante lorsque le sol en place est homogene. (auteur)

  14. Nuclear isomerism in fission fragments produced by the spontaneous fission of {sup 252}Cf; Isomerisme nucleaire dans les fragments de fission produits dans la fission spontanee du {sup 252}Cf

    Energy Technology Data Exchange (ETDEWEB)

    Gautherin, C

    1997-09-01

    This thesis is devoted to the study of the nuclear structure of neutron-rich nuclei, via the search of isomeric nuclear states. Neutron-rich nuclei were produced in the spontaneous fission of {sup 252}Cf. The experimental study of isomeric states in these nuclei was performed with the {gamma}-array EUROGAM II, coupled to an additional and original fission fragment detector composed by photovoltaic cells, SAPhIR. The photovoltaic cells are well adapted to detect low energy heavy ions and have good energy and time resolutions to obtain a good fission fragment detection. This experiment led to the discovery of new isomeric states in {sup 135}Xe, {sup 104}Mo, {sup 146,147,148}Ce and {sup 152,154,156}Nd, with lifetimes between 60 ns and 2 {mu}s. Level schemes of these nuclei have been completed. An interpretation of the isomeric states in the nuclei {sup 154,156}Nd and {sup 156,158}Sm was performed by Hartree-Fock-Bogolyubov calculations using the DIS Gogny force with two quasi-particles excitations. The confrontation with the experimental results led to an interpretation of these isomeric states as K-isomers. (author)

  15. The molten salt reactors (MSR) pyro chemistry and fuel cycle for innovative nuclear systems; Congres sur les reacteurs a sels fondus (RSF) pyrochimie et cycles des combustibles nucleaires du futur

    Energy Technology Data Exchange (ETDEWEB)

    Brossard, Ph. [GEDEON, Groupement de Recherche CEA CNRS EDF FRAMATOME (France); Garzenne, C.; Mouney, H. [and others

    2002-07-01

    In the frame of the studies on next generation nuclear systems, and especially for the molten salt reactors and for the integrated fuel cycle (as IFR), the fuel cycle constraints must be taken into account in the preliminary studies of the system to improve the cycle and reactor optimisation. Among the purposes for next generation nuclear systems, sustainability and waste (radio-toxicity and mass) management are important goals. These goals imply reprocessing and recycling strategies. The objectives of this workshop are to present and to share the different strategies and scenarios, the needs based on these scenarios, the experimental facilities available today or in the future and their capabilities, the needs for demonstration. It aims at: identifying the needs for fuel cycle based on solid fuel or liquid fuel, and especially, the on-line reprocessing or clean up for the molten salt reactors; assessing the state-of-the-art on the pyro-chemistry applied to solid fuel and to present the research activities; assessing the state-of-the-art on liquid fuels (or others), and to present the research activities; expressing the R and D programs for pyro-chemistry, molten salt, and also to propose innovative processes; and proposing some joint activities in the frame of GEDEON and PRACTIS programs. This document brings together the transparencies of 18 contributions dealing with: scenario studies with AMSTER concept (Scenarios, MSR, breeders (Th) and burners); fuel cycle for innovative systems; current reprocessing of spent nuclear fuel (SNF) in molten salts (review of pyro-chemistry processes (non nuclear and nuclear)); high temperature NMR spectroscopies in molten salts; reductive extraction of An from molten fluorides (salt - liquid metal extraction); electrochemistry characterisation; characterisation with physical methods - extraction coefficient and kinetics; electrolytic extraction; dissolution-precipitation of plutonium in the eutectic LiCl-KCl (dissolution and

  16. Problems to be Expected in Disposing of Fission Products from a Possible Nuclear Power Programme; Problemes Eventuels d'Elimination des Produits de Fission dans les Futures Centrales Nucleaires; 0412 0415 0420 041e 042f 0414 ; Problemas que Puede Plantear la Evacuacion de Productos de Fision Resultantes de la Ejecucion de un Programa de Produccion de Energia de Origen Nuclear

    Energy Technology Data Exchange (ETDEWEB)

    Dickson, G. K. [Cenral Technical Services, Engineering and Development Group, United Kingdom Atomic Energy Authority, Risley (United Kingdom)

    1960-07-01

    typical British nuclear power programme covering the next few decades is examined. The types of reactor to be erected and the types of fuel to be initially used in them are well appreciated but of course the author's conclusions will necessarily become less certain with the passage of time. The chemical processes which must be applied to irradiated fuels will depend on the type of fuel, its burn-up etc., and so will change during the period under review. Consideration is therefore given to the quantities of fission products and heavy isotopes which may be produced, the forms in which they may leave the chemical processing streams and the methods available for handling them safely, either by storage or by disposal. (author) [French] L'auteur examine un programme d'energie nucleaire caracteristique pour la Grande-Bretagne et s'etendant sur les prochaines decennies. Il donne une evaluation fort judicieuse des types de reacteurs dont la construction est envisagee et des genres de combustibles qu'il est question d'y utiliser pendant la periode initiale; toutefois, ses conclusions auront avec le temps de moins en moins de valeur. En effet, le traitement chimique auquel on devra soumettre le combustible irradie depend du genre de ce dernier, de son taux de combustion, etc.; il subira inevitablement des modifications au cours de la periode consideree. L'auteur tient donc compte des quantites de produits fissiles et d'isotopes lourds qu'il sera possible de produire, des formes sous lesquelles ils pourront se presenter a la fin du traitement chimique et des methodes existantes permettant d'assurer leur manipulation sans danger en vue de leur stockage ou de leur elimination. (author) [Spanish] Esta memoria estudia un programa britanico caracteristico de produccion de energia nuclear que cubre las proximas decadas. Se sabe con bastante certeza que tipos de reactores se construiran y el tipo de combustible que se empleara en ellos en un principio, pero estos conocimientos son

  17. Alterações vesicais na lesão medular experimental em ratos Urinary bladder changes in experimental spinal cord injury

    Directory of Open Access Journals (Sweden)

    Fernando Meyer

    2003-06-01

    Full Text Available O trauma raquemedular é uma das lesões traumáticas com maior impacto sobre a sociedade, o que faz com que enormes investimentos sejam feitos em estudos visando sua cura. Para a realização de pesquisas sobre lesão medular, é necessário que se utilize um modelo reprodutível desta lesão. A padronização de um sistema de lesão medular experimental provoca alterações não só no sistema nervoso mas também sistêmicas. OBJETIVO: O presente estudo visa avaliar as alterações vesicais na fase aguda da lesão medular experimental. MÉTODOS Foram utilizados 34 ratos Wistar machos divididos em grupo controle (A e grupo experimento (B. Enquanto os animais do grupo B foram submetidos à laminectomia no nível T9-T10 seguida de lesão medular, os do grupo A (n=4 foram submetidos somente à laminectomia. Os animais do grupo B foram dividos em 6 grupos distintos (n=5 e foram submetidos à eutanásia após 2, 4, 8, 24, 48 horas e 4 dias. RESULTADOS: Verificou-se redução da camada urotelial em todos animais do grupo B, presença de células inflamatórias e congestão vascular principalmente após 8 horas, entre outros achados. CONCLUSÃO: As alterações histológicas na fase aguda da lesão medular evidenciaram importante comprometimento vesical, sendo essa uma alteração sistêmica de relevância em lesados medulares.Spinal cord trauma is one of the lesions with highest socioeconomical impact. To develop research on spinal cord field it is mandatory to use a reproductible model for inducing lesions. Standardized spinal cord injury (SCI promotes changes not only in the nervous system but also systemic changes. PURPOSE: The aim of this study was to evaluate urinary bladder changes during the acute phase of experimental spinal cord injury. METHODS: Thirty four Wistar male rats were allocated in 2 groups: controll (A and experiment (B. While animals from group B underwent laminectomy at T9-T10 level followed by SCI, group A underwent only

  18. Regulatory oversight report 2009 concerning nuclear safety in Swiss nuclear installations; Aufsichtsbericht 2009 zur nuklearen Sicherheit in den schweizerischen Kernanlagen/Rapport de surveillance 2009 sur la securite nucleaire dans les installations nucleaires en Suisse/Regulatory oversight report 2009 concerning nuclear safety in Swiss nuclear installations

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2010-04-15

    nuclear facilities in Switzerland. Chapter 9 provides an update on the three applications submitted so far for the outline approval of a new nuclear power plant. Chapter 10 provides information on the geological repository for radioactive waste and Chapter 11 deals with generic aspects not specific to any individual facility. The overall nuclear safety of the Beznau and Goesgen NPPs is rated as satisfactory. Based on its Systematic Safety Reviews at the Leibstadt and Muehleberg plants, ENSI rates their operating safety as good. All these facilities complied with their operating licenses. The licensees complied with the statutory reporting requirements, with exception of the Goesgen NPP which delayed notification of an incident in 2008 by several months. In 2009 there were 22 notifiable incidents at NPPs: 11 incidents occurred at Beznau NPP, 4 at Muehleberg, 3 at Goesgen, and 4 at Leibstadt. The incident at Beznau on 3 August 2009 was rated at Level 2 on INES scale, the one at Goesgen on 24 June 2008, where notification was delayed, was rated at level 1 on INES, and the remaining incidents during 2009 were rated as INES 0. ZWILAG consists of several interim storage halls, a conditioning plant, and the plasma plant. At the end of 2009, the cask storage hall contained 33 transport/storage casks with spent fuel assemblies and vitrified residue packages as well as 6 casks with decommissioned waste from the former experimental NPP at Lucens. About 16% of the capacity of the HLW store and about 21% of the capacity of the ILW store were occupied. The nuclear safety of the storage buildings and the hot cell was good. During 2009, there were 3 notifiable incidents at ZWILAG. In 2009 ENSI granted approval for the unrestricted use of the plasma plant. ZWILAG conducted two operations to process, incinerate and melt radioactive waste. At PSI the decommissioning work at the two research reactors DIORIT and SAPHIR continued smoothly. Experiments on the PROTEUS research reactor were

  19. Thermal Bremsstrahlung probing nuclear multifragmentation in nucleus-nucleus collisions around the Fermi energy; Bremsstrahlung thermique comme sonde de la multifragmentation nucleaire dans les collisions noyau-noyau aux energies de Fermi

    Energy Technology Data Exchange (ETDEWEB)

    D' Enterria, D.G

    2000-05-15

    The thermodynamical properties of nuclear matter at moderate temperatures and densities, in the vicinity of the predicted nuclear liquid-gas phase transition, are studied using as experimental probe the hard-photons (E{sub {gamma}} > 30 MeV) emitted in nucleus-nucleus collisions. Photon and charged-particle production in four different heavy-ion reactions (Ar{sup 36} + Au{sup 197}, Ag{sup 107}, Ni{sup 58}, C{sup 12} at 60 A*MeV) is measured exclusively and inclusively coupling the TAPS photon spectrometer with two charged-particle and intermediate-mass-fragment detectors covering nearly 4{pi}. We confirm that Bremsstrahlung emission in first-chance (off-equilibrium) proton-neutron collisions (pn{gamma}) is the dominant origin of hard photons. We also firmly establish the existence of a thermal radiation component emitted in second-chance proton-neutron collisions. This thermal Bremsstrahlung emission takes place in semi-central and central nucleus-nucleus reactions involving heavy targets. We exploit this observation i) to demonstrate that thermal equilibrium is reached during the reaction, ii) to establish a new thermometer of nuclear matter based on Bremsstrahlung photons, iii) to derive the thermodynamical properties of the excited nuclear sources and, in particular, to establish a 'caloric curve' (temperature versus excitation energy), and iv) to assess the time-scales of the nuclear break-up process. (author)

  20. A mathematical model for cost of maritime transport. Application to competitiveness of nuclear vessels; Modele mathematique du cout de transport maritime application a la competitivite du navire nucleaire

    Energy Technology Data Exchange (ETDEWEB)

    Dorval, C [Commissariat a l' Energie Atomique, 75 - Paris (France)

    1966-05-01

    In studying the competitiveness of a nuclear merchant vessel, economic assessments in terms of figures were discarded in favor of a simplified model, which gives a clearer idea of the mechanism of the comparison between alternative vessels and the particular influence of each parameter. An expression is formulated for the unit cost per ton carried over a given distance as a function of the variables (speed and deadweight tonnage) and is used to determine the optima for conventional and nuclear vessels. To represent the freight market involved in the optimization studies, and thus in the competitiveness computation, two cases are taken into account: the tonnage to be carried annually is limited, and the tonnage to be carried annually is not limited. In both cases the optima are calculated and compared for a conventional and a nuclear vessel. Competitiveness curves are plotted as a function of the ratios of nuclear and conventional fuel costs and nuclear and conventional marginal power costs. These curves express the limiting values of the above two ratios for which the transport costs of the nuclear and conventional vessels are equal. The competitiveness curves vary considerably according to the hypothesis adopted for the freight market and the limit of tonnage carried annually. (author) [French] Pour etudier la competitivite du navire marchand nucleaire, plutot que de nous livrer a des evaluations economiques chiffrees, discutables dans l'etat actuel des etudes, nous utilisons un modele simplifie permettant de mieux saisir le mecanisme de la comparaison des navires et l'influence particuliere de chaque parametre. Nous etablissons une expression du cout unitaire de la tonne transportee sur un parcours donne en fonction des variables vitesse et port en lourd. Et nous l'utilisons pour determiner les optima des navires classiques et nucleaires. Pour representer le marche du fret qui intervient dans les etudes d'optimisation, et donc dans la recherche de la

  1. Contribution to the study of the effects of {alpha}-irradiation in nuclear glasses; Contribution a l'etude des effets de l'irradiation {alpha} sur les verres nucleaires

    Energy Technology Data Exchange (ETDEWEB)

    Abbas, A

    2001-07-01

    The main topic of this work is to characterise the effects of {alpha}-disintegration in nuclear waste glasses. Experimental and numerical approaches have been considered. The structure of the French nuclear waste glass (R7T7) has been simulated using four- and six-oxides simplified glasses which contain the main elements of the R7T7 glass: SiO{sub 2}, B{sub 2}O{sub 3}, Na{sub 2}O, ZrO{sub 2}, Al{sub 2}O{sub 3} and CaO. Four- and six-oxides glasses have been irradiated with 1 MeV-He{sup +} (ionisation) and 2.1 MeV-Kr{sup 3+} (ionisation and atomic collisions) ions in order to reproduce the effects of the {alpha}-particle and of the recoil nucleus emitted during {alpha}-disintegration of actinides, and also to differentiate electronic and ballistic effects. Irradiated glasses have been characterised using several techniques, which have been adapted to the peculiarities of our samples (isolated material, small irradiated depth). The results point out the salient role of sodium in the observed modifications: depth concentration profiles obtained with RBS show an accumulation of sodium at the irradiated surface. We found a apparent acceleration of sodium release in leaching experiments which confirm that point. Modifications observed in Raman spectra of irradiated glasses show an increase of the polymerisation (increase of Q{sub 3}/Q{sub 2} ratio) due to sodium migration. In simplified glasses we have found that the modifications of mechanical properties by external irradiations reproduce the modifications observed in actinide doped nuclear glass (decrease of hardness and increase of fracture toughness). At the same time, we performed Molecular Dynamics simulations of a six-oxides glass. We have shown that the surface modifies the glass structure down to a depth of 10 Angstrom: modification of depth concentration profiles, decrease of the atomic coordination number (A1, B and Si). During cascades, we found that atomic displacements are easier near the surface. This

  2. Contribution to the study of thermal mixing between nuclear spin systems; Contribution a l'etude du melange thermique entre systemes de spins nucleaires

    Energy Technology Data Exchange (ETDEWEB)

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

    1967-02-15

    This work describes methods of dynamic nuclear polarization in solids based on the thermal mixing between nuclear spin systems. The description of the thermal mixing processes involves most of the fundamental aspects of the spin temperature theory. The experiments, conducted with paradichlorobenzene and para-dibromobenzene, yield a detailed confirmation of the theoretical predictions. (author) [French] Ce travail decrit des methodes de polarisation dynamique nucleaire dans les solides basees sur le melange thermique entre systemes de spins nucleaires. La description des processus de melange thermique met en jeu la plupart des aspects fondamentaux de la theorie de la temperature de spin. Les experiences, realisees avec du paradichlorobenzene et du paradibromobenzene, apportent une confirmation detaillee des previsions theoriques. (auteur)

  3. A critical summary of microscopic fast-neutron interactions with reactor structural, fissile and fertile materials; Apercu critique des interactions microscopiques des neutrons rapides avec les materiaux de construction et les matieres fissiles et fertiles utilisees dans les reacteurs; Kriticheskij obzor mikroskopicheskog o vzaimodejstviya bystrykh nejtronov s konstruktsionnymi, rasshcheplyayushchimis ya i vosproizvodyashchim i reaktornymi materialami; Resumen critico de las interacciones microscopicas de los neutrones rapidos con los materiales estructurales fisionables y fertiles utilizados en los reactores

    Energy Technology Data Exchange (ETDEWEB)

    Smith, A B [Argonne National Laboratory, Argonne, IL (United States)

    1962-03-15

    Prevailing knowledge of fast-neutron-induced reactions utilized in the nuclear design of reactor systems is reviewed. Principal emphasis is placed upon microscopic experimental methods, results and precisions. Fast-neutron scattering is considered in detail, including the results of experimental determinations of scattering from oxygen, iron, zirconium, niobium, tungsten, thorium and uranium. Representative results of experimental studies of fast-neutron capture and fast-neutron-induced fission are given. The measurements discussed not only provide results of considerable applied usefulness but axe also examples of the application of advanced experimental nuclear techniques. Areas of limited, conflicting or non-existent experimental information are outlined. A prognosis of future knowledge of fast-neutron reactions is made, with emphasis on the fulfillment of reactor requirements for basic nuclear data. (author) [French] L'auteur fait le point des connaissances sur les reactions provoquees par les neutrons rapides sur lesquelles on tend a fonder les projets de reacteurs. Il met en relief les methodes, les resultats et la precision de mesures experimentales a l'echelle microscopique. Il etudie en detail la diffusion des neutrons rapides, et donne les resultats de mesures experimentales de diffusion dans l'oxygene, le fer, le zirconium, le niobium, le tungstene, le thorium et l'uranium. Il donne les resultats les plus significatifs d'etudes experimentales sur la capture des neutrons rapides et sur la fission provoquee par des neutrons rapides. Les mesures etudiees, non seulement fournissent des renseignements d'une utilite pratique considerable, mais aussi constituent des exemples de l'application de techniques experimentales nucleaires a la pointe du progres. L'auteur indique les domaines ou les donnees experimentales sont limitees, contradictoires ou inexistantes. Il se livre a des pronostics sur le developpement des connaissances experimentales en matiere de

  4. Chemical Effects of Nuclear Recoil in Organic Halide Systems: A New Theoretical Treatment and Experimental Verification of the Theory; Effets Chimiques du Recul Nucleaire dans des Systemes Organiques Halogenes: Nouveau Traitement Theorique et Verification Experimentale de la Theorie; Khimicheskie vozdejstviya yadernoj otdachi v organicheskikh galoidnykh sistemakh: novoe teoreticheskoe tolkovanie i ehksperimental'noe podtverzhdenie teorii; Efectos Quimicos del Retroceso Nuclear en Sistemas de Haluros Organicos: Nuevo Tratamiento Teorico y Verificacion Experimental de la Teoria

    Energy Technology Data Exchange (ETDEWEB)

    Kontis, S. S.; Sanitwongs, P.; Weston, M. [Londonderry Laboratory for Radiochemistry, University of Durham, Durham (United Kingdom)

    1965-04-15

    Methods have been developed for calculating the organic retention of radiohalogen to be expected following neutron activation of mixtures of two organic halides and the corresponding free halogen. The methods are based on the concepts of the Libby ''billiard-ball'' process of hot-atom labelling and retentions are expressed in terms of two types of parameters: (1) the fractional chance that collision of a hot radiohalogen atom with a particular molecule will lead to retention of the hot atom in that molecule; (2) the upper and lower energy limits for what is termed a hot bromine atom. It is shown how the former type of parameter may be derived from experiments with binary mixtures of an organic halide and the corresponding free halogen: the second type of parameter must be deduced from nuclear and chemical data. These methods have been tested by studies on the systems C{sub 2}H{sub 5}Br/CCl{sub 4}/Br{sub 2} and C{sub 2}H{sub 5}Br/C{sub 6}H{sub 5}Br/Br{sub 2}. The calculated retentions (using parameters derived from studies of the systems C{sub 2}H{sub 5}Br/Br{sub 2}, CCl{sub 4}/Br{sub 2} and C{sub 6}H{sub 5}Br/Br{sub 2}) are in good agreement with those found experimentally in mixtures with a bromine mole-fraction greater than about 0.1. It is therefore considered that the Libby mechanism is adequate to explain the observed organic retentions in such mixtures. As the bromine mole-fraction is reduced, below 0.1 the observed retentions become progressively higher than calculated values. This is attributed to there being additional modes of hot-atom labelling which become operative when the bromine concentration is not high enough to give adequate radical scavenging. (author) [French] Lesauteuts ont mis au point des methodes pour calculer la retention organique du radiohalogene a laquelle on peut s'attendre apres activation par les neutrons de melanges de deux halogenures organiques et de l'halogene libre correspondant. Ces methodes sont basees sur les principes du

  5. Non-nuclear energies; Les energies autres que le nucleaire

    Energy Technology Data Exchange (ETDEWEB)

    Nifenecker, H. [Laboratoire de Physique Subatomique et de Cosmologie, IN2P3-CNRS/UJF/INPG, 53 av. des Martyrs, 38026 Grenoble Cedex and Sauvons le Climat (http://www.sauvonsleclimat.org), Grenoble (France)

    2007-07-01

    The different meanings of the word 'energy', as understood by economists, are reviewed and explained. Present rates of consumption of fossil and nuclear fuels are given as well as corresponding reserves and resources. The time left before exhaustion of these reserves is calculated for different energy consumption scenarios. On finds that coal and nuclear only allow to reach the end of this century. Without specific dispositions, the predicted massive use of coal is not compatible with any admissible value of global heating. Thus, we discuss the clean coal techniques, including carbon dioxide capture and storage. One proceeds with the discussion of availability and feasibility of renewable energies, with special attention to electricity production. One distinguishes controllable renewable energies from those which are intermittent. Among the first we find hydroelectricity, biomass, and geothermal and among the second, wind and solar. At world level, hydroelectricity will, most probably, remain the main renewable contributor to electricity production. Photovoltaic is extremely promising for providing villages remote deprived from access to a centralized network. Biomass should be an important source of bio-fuels. Geothermal energy should be an interesting source of low temperature heat. Development of wind energy will be inhibited by the lack of cheap and massive electricity storage; its contribution should not exceed 10% of electricity production. Its present development is totally dependent upon massive public support. A large part of this paper follows chapters of the monograph 'L'energie de demain: technique, environnement, economie', EDP Sciences, 2005. (author)

  6. The Problems of Controlling Defects in the Materials Used for the First Czechoslovak Nuclear-Power Station; Problemes de Controle des Defauts dans les Materiaux Utilises a la Premiere Centrale Nucleaire de Tchecoslovaquie; Problemy defektoskopicheskogo kontrolya stroitel'nykh materialov reaktora pervoj chekhoslovatskoj atomnoj ehlektrostantsii; Problemas de Control de Defectos en los Materiales Utilizados en la Primera Central Nuclear de Checoslovaquia

    Energy Technology Data Exchange (ETDEWEB)

    Radislav, Filipp [Zavody Im.V.I. Lenina, Pl' zen, Czechoslovakia (Czech Republic)

    1965-09-15

    cassettes. In radiographing thick welds, betatrons of Czechoslovak manufacture are used. The paper describes the methods used for testing and the results obtained and compares the Czechoslovak 15-MeV betatron with the Siemens' betatron. (author) [French] Le memoire donne une description succincte de la cuve du reacteur de la premiere centrale nucleaire de Tchecoslovaquie. En raison des specifications rigoureuses auxquelles doivent repondre les methodes de construction et d'assemblage de la cuve du reacteur, en acier inoxydable faiblement allie de grande epaisseur (650 mm), il a fallu elaborer une methode de controle non destructif du materiau de base et des soudures, fondes sur l'emploi de ' temoins ' . Pour controler la qualite du materiau de base et des sourdures, on utilise essentiellement des ultrasons puises et une sonde. Le memoire decrit les methodes d'essais et l'evaluation des donnees au cours de l'examen du materiau de base, ainsi que le procede qui permet de verifier la qualite des soudures electriques a scorie, des soudures en atmosphere de gaz carbonique et des soudures a l'arc faites a la main. Le controle des plaques forgees et laminees se fait au moyen d'un dispositif automatique de defectoscopie qui a ete mis au point en Tchecoslovaquie. Ce dispositif se compose de deux parties: un mecanisme mobile et un detecteur a ultrasons du type U1D-A2, de fabrication tchecoslovaque. Il comprend plusieurs elements inedits. On a compense l'effet de la distance sur l'ampleur du signal declenche par un defaut de maniere que cette ampleur reste constante. On a compense aussi l'effet du aux irregularites de la liaison acoustique, les impulsions etant communiquees a un dispositif d'enregistrement a distance. L'importance du defaut est evalue a l'aide d'unattenuateur. On metau point un dispositif automatique pour controler une surface cylindrique verticale. Les soudures d'assemblage circulaire doivent etre verifiees a une temperature elevee. Dans les usines V. I. Lenine de

  7. Contribution to the study of solid helium-3 by nuclear magnetic resonance; Contribution a l'etude de l'helium trois solide par resonance magnetique nucleaire

    Energy Technology Data Exchange (ETDEWEB)

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

    1968-07-01

    Due to the unusually large zero point motion of helium three atoms in the solid, the overlap of the atomic wave functions is very important. As a consequence, there are exchange interactions, the theoretical calculation and the experimental measurement of which are discussed. Nuclear magnetic resonance is especially well suited for the latter.A detailed theory is given for both exchange narrowing and Zeeman-exchange cross relaxation, which phenomena are used to measure the exchange interaction as a function of molar volume. The alignment temperature is thus known; it goes down when the pressure goes up and is never higher than three milli degrees. An influence of helium four impurities on the exchange interactions between helium three atoms which are neighbours of the substitutional He is shown. (author) [French] Par suite de l'amplitude exceptionnelle des mouvements de point zero dans l'helium trois solide, le recouvrement des fonctions d'onde atomiques est tres important. Il en resulte des interactions d' echange dont on discute l'evaluation theorique et la mise en evidence experimentale. Cette derniere peut se faire par resonance magnetique; on etudie theoriquement les phenomenes de retrecissement par echange et de relaxation Zeeman-echange que l'on met a profit pour determiner les interactions d'echange en fonction du volume molaire. On en deduit que la temperature d'alignement nucleaire diminue quand on comprime le solide et est au plus de 3x10{sup -3} K. L'influence des impuretes d'helium quatre sur les interactions d'echange entre atomes {sup 3}He voisins de {sup 4}He est mise en evidence. (auteur)

  8. Nuclear Accident Dosimetry at Argonne National Laboratory; Dosimetrie dans les Cas d'Accidents Nucleaires au Laboratoire National d'Argonne; 0421 041b 0423 0416 0411 0410 0414 ; Dosimetria en Casos de Accidente Nuclear en el Laboratorio Nacional de Argonne

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, L. L.; Duffy, T. L.; Sedlet, J.; O' Neil, D. P. [Argonne National Laboratory, Argonne, IL (United States)

    1965-06-15

    This report summarizes current planning at Argonne National Laboratory with respect to dose determination following a criticality incident. The discussion relates chiefly to two types of commercially obtained dosimeter packages, and includes the results of independent calibrations performed at the Laboratory. The primary dosimeter system incorporates threshold detectors developed at Oak Ridge National Laboratory for neutron spectrum measurement. Fission foil decay calibration curves have been determined experimentally for scintillation counting equipment routinely used at Argonne. This equipment also has been calibrated for determination of sodium-24 activity in blood. Dosimeter units of the type designed at Savannah River Laboratory are deployed as secondary stations. Data from the neutron activation components of these units will be used to make corrections to, the neutron spectrum for intermediate as well as thermal energies. The epicadmium copper foil activation, for a given fluence of intermediate energy neutrons, has been shown relatively insensitive to neutron spectrum variations within the region, and a meaningful average of copper cross-section has been determined. Counter calibration factors determined at Argonne are presented for the copper, indium, and sulphur components. The total neutron fluence is computed using the corrected spectrum in conjunction with a capture probability function and the blood sodium result. One or more specifications of neutron dose then may be calculated by applying the spectral information to the appropriate conversion function. The gamma portion of the primary dosimeter package contains fluorescent rods and a thermoluminescent dosimeter in addition to a two-phase chemical dosimeter. The gamma dosimeter in the secondary package is a polyacrylamide solution which is degraded by exposure to gamma radiation. The absorbed dose is derived from a measured change insolution viscosity. Difficulties in evaluation, placement, and

  9. France's nuclear power programme; Le programme nucleaire francais

    Energy Technology Data Exchange (ETDEWEB)

    Cabanius, J [Electricite de France (EDF), 75 - Paris (France); Horowitz, J [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1964-07-01

    -increasing importance, by using the country's resources of natural uranium, and later plutonium, to the best ends. (authors) [French] Les perspectives d'evolution de la consommation d'energie electrique francaise confirment l'aggravation du deficit des ressources energetiques metropolitaines. Les centrales nucleaires doivent permettre de diminuer ce deficit si un certain nombre d'incertitudes actuelles sont levees. Le premier programme presente par MM AILLERET et TARANGER a la Conference de Geneve en 1955 visait la mise en service pour 1965 de 850 MWe; il a ete consacre au developpement de la filiere uranium naturel - graphite - gaz et s'acheve avec la realisation d'EDF 3, premiere unite capable de 500 MWe engagee dans le monde. Avant de passer du stade des prototypes a celui des duplications, ELECTRICITE DE FRANCE a decide, en accord avec le COMMISSARIAT A L'ENERGIE ATOMIQUE, la realisation d'EDF 4 qui, en reprenant la partie reacteur d'EDF 3 ainsi que l'appareil de chargement et de dechargement, l'ensemble de controle et divers materiels, apporte une innovation importante en incorporant les echangeurs et les soufflantes a l'interieur du caisson en beton precontraint contenant le coeur. En meme temps, les etudes se poursuivent dans cette meme filiere et laissent entrevoir les possibilites d'utiliser un nouvel element combustible annulaire dont l'emploi ameliorerait notablement les performances d'EDF 5. Dans la filiere eau lourde, la realisation d'EL 4 a Brennilis par le COMMISSARIAT A L'ENERGIE ATOMIQUE et ELECTRICITE DE FRANCE se poursuit. Les etudes d'un reacteur de 500 MWe de cette filiere ont deja commence. Dans la filiere a eau pressurisee, la centrale de CHOOZ est realisee en association par ELECTRICITE DE FRANCE et les Producteurs Belges. Enfin, le COMMISSARIAT A L'ENERGIE ATOMIQUE poursuit a Cadarache la realisation du surgenerateur 'Rapsodie' et les etudes d'un reacteur de puissance plus important. Ainsi, les connaissances techniques et economiques acquises dans ces diverses

  10. Nuclear study of Melusine; Etude nucleaire de Melusine

    Energy Technology Data Exchange (ETDEWEB)

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

    1959-07-01

    In this report are reviewed - with respect to starting of experiments - the main nuclear characteristics of a 20 per cent enriched uranium lattice, with light water as moderator and reflector. The reactor is to operate at 1 MW. 1) Study of various critical masses. 2) Control. Effectiveness of cadmium. Control rods and of a stainless steel regulating rod. 3) Study of the effect on reactivity of disturbances in the core center. 4) Study of xenon and samarium poisoning. 5) Temperature factor. 6) Heat exchanges in a fuel element. (author) [French] On etudie, dans ce rapport, les principales proprietes nucleaires d'un reseau a uranium enrichi (20 pour cent), dont le moderateur et le reflecteur sont l'eau legere en vue des experiences de demarrage. Ce reacteur devra fonctionner a 1 MW. 1) Etude de diverses masses critiques. 2) Controle. Efficacite des barres de controle en cadmium et d'une barre de reglage en acier inoxydable. 3) Etude de l'effet sur la reactivite de perturbation au centre du coeur. 4) Etude de l'empoisonnement xenon et samarium. 5) Coefficient de temperature. 6) Echanges thermiques dans un element. (auteur)

  11. The Radioisotopic Determination of Diffusion Coefficients and Currents in Natural Waters. Surface Collection of Radioactive Fall-Out on a Large Alpine Lake; Determination par detection nucleaire des coefficients de diffusion et des courants dans les eaux naturelles. Evolution de la surface de collection d'un grand lac alpin pour les retombees radioactives; Opredelenie koehffitsienta diffuzii i skorosti techeniya estestvennykh vod pri pomoshchi yadernogo detektirovaniya. Ehvolyutsiya poverkhnosti sbora radioaktivnykh osadkov na bol'shom al'pijskom ozere; Determinacion por deteccion nuclear de los coeficientes de difusion y de las corrientes en las aguas naturales evolucion de la superficie de captacion de un gran lago alpino para las precipitaciones radiactivas

    Energy Technology Data Exchange (ETDEWEB)

    Chesselet, R.; Nordemann, D. [Service d' Electronique Physique, Centre d' Etudes Nucleaires de Saclay (France); Dussart, B. [Centre de Recherches Hydrobiologiques, CNRS, Gif-sur-Yvette (France)

    1963-08-15

    'un coefficient de diffusion pour l'emetteur utilise et a la mesure eventuelle de la vitesse du courant au point ou la mesure est effectuee (dans le cas decrit, le lac Leman). Dans une seconde etape, en correlation avec une etude de geophysique concernant le probleme general des retombees radioactives, les auteurs ont utilise l'apport des retombees radioactives ayant pour origine les essais nucleaires atmospheriques (octobre 1961-janvier 1962). Des mesures de la radioactivite ont ete effectuees chaque jour sur des prelevements d'eau du lac Leman a des profondeurs de 0 m, 10 m, 20 m et sur un collecteur de retombees atmospheriques seches et humides. Malgre la complexite du regime des apports en fonction du temps, l'interpretation des diagrammes obtenus peut contribuer a resoudre le probleme du devenir des produits radioactifs dans les conditions de diffusion et de courants rencontrees. L'utilisation de la diffusion de produits radioactifs en tres faibles quantites et des differentes techniques de detection nucleaires a haute sensibilite actuellement disponibles peut conduire a une meilleure connaissance de la diffusion in situ et du mouvement des masses d'eaux naturelles. (author) [Spanish] En una primera etapa, los autores ha i provecado la difusion in situ de un emisor radiactivo, el sodio-22 en forma de Na{sup +}, de actividad muy baja (inferior al milicurie). La aplicacion de las leyes de la difusion a este caso facilita el calculo de la velocidad de difusion de la ''nube radiactiva''. Por consiguiente, el registro en funcion del tiempo de las actividades medidas con dos detectores gamma dispuestos de modo conveniente permite asignar un coeficiente de difusion ai emisor empleado y, eventualmente, evaluar la velocidad de la corriente en el punto en que se efectua la medicion (en el caso descrito, el lago Leman). En una segunda etapa, en relacion con un estudio geofisico del problema general de las precipitaciones radiactivas, los autores utilizaron la aportacion de las

  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. Neutron noise in nuclear reactors; Le bruit neutronique des reacteurs nucleaires

    Energy Technology Data Exchange (ETDEWEB)

    Blaquiere, A. [Institut National des Sciences et Techniques Nucleaires (France); Pachowska, R. [Universite Technique de Varsovie (Poland)

    1961-06-15

    The power of a nuclear reactor, in the operating conditions, presents fluctuations due to various causes. This random behaviour can be included in the study of 'noises'. Among other sources of noise, we analyse hereafter the fluctuations due: a) to the discontinuous emissions of neutrons from an independent source; b) to the multiplication of neutrons inside the reactor. The method which we present makes use of the analogies between the rules governing a nuclear reactor in operation and a number of radio-electrical systems, in particular the feed-back loops. The reactor can be characterized by its 'passing band' and is described as a system submitted to a sequence of random pulses. In non linear operating condition, the effect of neutron noise is defined by means of a non-linear functional, this theory is thus related to previous works the references of which are given at the end of the present report. This leads us in particular in the case of nuclear reactors to some results given by A. Blaquiere in the case of radio-electrical loops. (author) [French] La puissance d'un reacteur nucleaire, dans les conditions du regime, est affectee de fluctuations dont les causes sont tres diverses. Ce comportement aleatoire rentre dans le cadre general de l'etude des 'bruits'. Entre autres sources ce bruit, nous analysons ici les fluctuations dues: a) a l'emission discontinue des neutrons provenant d'une source autonome; b) a la multiplication des neutrons au sein du reacteur. La methode que nous introduisons exploite les analogies entre les lois qui regissent un reacteur nucleaire au regime et certains systemes radioelectriques, en particulier les circuits a boucle de reaction. Le reacteur est caracterise par sa 'bande passante' et est decrit comme un systeme soumis a une succession d'impulsions aleatoires. Dans les conditions de fonctionnement non lineaires, l'effet du bruit neutronique est precise en utilisant une fonctionnelle non lineaire, ce qui relie cette theorie a

  14. First session: needs for experimental programs; Session 1: Les besoins et programmes experimentaux

    Energy Technology Data Exchange (ETDEWEB)

    Waeckel, N.; Beguin, S.; Delbecq, M. [Electricite de France (EDF), 92 - Clamart (France); Assedo, R.; Hittner, D. [AREVA/FRAMATOME, 92 - La Defense (France); Carre, F.; Renault, C. [CEA Saclay, Dir. du Developpement et de l' Innovation Nucleares (DEN/DDIN/DPSF), 91 - Gif Sur Yvette (France); Bardelay, J. [Institut de Radioprotection et de Surete Nucleaire (IRSN/DSRE), 92 - Fontenay-aux-Roses (France)

    2005-07-01

    Adequate experimental facilities for material irradiation or material / system qualification must be available, first for the development of the current PWR-type reactor concerning the extension of its operating life, the optimization of its nuclear fuel and its capacity to fit the power demand, secondly for the development of the fourth generation of reactors which implies important experimental research work particularly in the fields of: - new nuclear fuels particularly nitrides and carbides, - materials able to sustain high and very high temperatures, - high temperature helium cooling systems, or - feasibility studies for a completely closed fuel cycle inside the reactor core allowing both a complete recycling and the separation of actinides. (A.C.)

  15. Review of Development Status of Nuclear Superheat; Expose sur l'etat actuel des travaux concernant la surchauffe nucleaire; Obzor razrabotki voprosa o yadernykh peregrevatelyakh; Estudio de los progresos realizados en niateria de sobrecalentamiento nuclear

    Energy Technology Data Exchange (ETDEWEB)

    Imhoff, D. H.; Pennington, R. T. [General Electric Company, San Jose, CA (United States)

    1963-10-15

    fuel irradiation performance, in-pile and out-of-pile uniform and localized corrosion evaluations, results from thermal superheat critical experiments, results from experimental heat-transfer testing and a brief appraisal of the economic incentives of the separate superheat reactor, integral superheat reactor, and mixed-spectrum superheat reactor design studies. (b) A brief description is given of the USAEC-Sponsored ESADA-VESR nuclear superheat fuel development programme. The development tasks, the initial core superheat fuel-element design, the range of experimental variables, and the expected results for the three-year fuel development programme are discussed. (author [French] Depuis 1959, la Societe General Electric s'occupe activement de mettre au point la surchauffe nucleaire dans les reacteurs ralentis a l'eau ordinaire. A cette epoque, le ''Superheat Advance Demonstration Experiment'' (SADE), finance par la societe, a permis d'obtenir, pour la premiere fois aux Etats-Unis, de la vapeur surchauffee par un dispositif nucleaire. Les auteurs du memoire font le point de la situation actuelle concernant la surchauffe nucleaire. Ils decrivent, dans une premiere partie, les trois principales installations de surchauffe nucleaire utilisees par la General Electric et, dans la seconde, les deux principaux programmes de recherches sur la surchauffe ainsi que les resultats les plus importants obtenus jusqu'ici dans ce domaine. 1. Principales installations pour les experiences de surchauffe: a) Breve description du SADE utilise dans le reacteur a eau bouillante de Vallecitos (VBWR), avec tableaux des conditions dans lesquelles se deroulent les experiences, et des elements combustibles irradies pendant la periode comprise entre mai 1959 et juin 1962; puis examen critique des resultats les plus importants ainsi obtenus. b) Breve description de l' ''Expanded Superheat Advance Demonstration Experiment'' (E-SADE) installe dans le reacteur de Vallecitos, avec tableaux des

  16. Nuclear Materials Management and its Relationship to Nuclear Safety and Criticality Control; La Gestion des Matieres Nucleaires et ses Rapports avec la Securite Nucleaire et le Controle de la Criticite; Obrashchenie s yadernymi materialami i ego svyaz' s yadernoj bezopasnost'yu i kontrolem nad kritichnost'yu; La Administracion de Materiales Nucleares y sus Relaciones con la Seguridad Nuclear y el Control de la Criticidad

    Energy Technology Data Exchange (ETDEWEB)

    Tingey, F. H. [Phillips Petroleum Company, Idaho Falls, ID (United States)

    1966-02-15

    dictated by the technical considerations and familiar with the operational limitations. The administrative problems are solved through procedural restrictions placed by the supervisor. The NMM office can be most valuable in further support to the supervisor in these activities. The primary responsibility of this office is to alert responsible supervision to potentially hazardous situations as indicated either from information made available through the routine processing of accountability data or from material balance calculations. Any information pertaining to criticality studies as requested from the NMM office must be accurate and precise. A vigorous inventory management policy must be pursued to lessen the problems presented by accumulation of fissile materials. Internal audit by the NMM staff of inventory holdings can also serve to verify adherence to safeguard procedures. A vigorous orientation programme can be implemented by the NMM staff in its dealing with those individuals handling nuclear materials to make them more aware of the hazards involved. The integration of the NMM group into the general criticality safeguard problems at the NRT and has provided an effective system for assisting the line supervision in discharging this very important responsibility. (author) [French] Il est essentiel pour tous ceux qui travaillent dans l'industrie nucleaire de savoir comment eviter que des matieres nucleaires ne se trouvent rassemblees en quantites, selon une geometrie ou dans un milieu tels qu'elles puissent donner lieu a une reaction neutronique en chaine. Ceci interesse tout particulierement ceux qui, dans l'exercice de leurs fonctions, sont responsables de la manipulation, du transfert et de l'entreposage des matieres fissiles. Ces memes personnes participent au systeme de gestion des matieres nucleaires. Elles ont au premier chef la responsabilite de fournir et de recevoir les donnees comptables par l'intermediaire du service de gestion des matieres nucleaires

  17. Evolution of nuclear chemical industry in France; Evolution de l'industrie chimique nucleaire en France

    Energy Technology Data Exchange (ETDEWEB)

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

    1959-07-01

    'impulsion du CEA, mais aussi de maitres d'oeuvres tels qu'Electricite de France et la Marine Marchande, l'effort nucleaire fran is atteint pour les annees 1957-1961, environ 600 milliards de francs: plus de la moitie de cette somme sera depensee par l'industrie chimique en recherches, installations pilotes, constructions d'usines et livraisons. Faire bien, vite et rentable sont les buts recherches. Ces objectifs sont atteints grace a une collaboration intime des grands services de l'etat et de l'industrie privee. Ce gros effort s'exerce principalement dans les voies suivantes: - Un traitement chimique pousse de tonnages croissants des minerais de l'Union fran ise, visant a produire un uranium pur, abondant et bon marche. - Une preparation soigneuse de combustibles nucleaires economiques et parfaitement adaptes aux divers types de reacteurs en fonctionnement ou en construction. - Un retraitement des combustibles irradies pour en extraire le plutonium de facon complete ainsi que l'uranium et certains produits de fission. - Une fabrication industrielle des materiaux nucleairement purs ou resistants a la corrosion exiges par la technologie des reacteurs producteurs d'energie et de recherches. - La fourniture aux multiples utilisateurs etrangers et fran is d'isotopes et de traceurs radioactifs reclames par la medecine, l'industrie et l'agriculture en nombre toujours croissant. - Un traitement chimique meticuleux des effluents gazeux ou liquides dans des stations au controle rigoureux afin de rendre les reacteurs et leurs annexes parfaitement surs d'emploi. Cet expose aura montre l'ampleur de l'effort deploye par une industrie chimique nucleaire jeune, dynamique et en plein essor. Ayant assure ses techniques, realise de nombreuses installations, elle est largement en etat de faire face au programme atomique fran is. En outre, elle est capable et desireuse d'etre associee aux developpements de l'industrie atomique etrangere notamment dans te cadre de l'Euratom et d

  18. Theoretical and Experimental Studies of High-Frequency Plasma Structures; Etudes Theoriques et Experimentales sur les Structures HF a Plasma

    Energy Technology Data Exchange (ETDEWEB)

    Consoli, T. [CEA, Centre d' Etudes Nucleaires de Saclay (France)

    1969-03-15

    The author has studied high-frequency structures at the resonance {omega}{sub ec} = {omega}{sub HF} in an inhomogeneous magnetic field. The following points have been developed theoretically: the complete (relativistic and non-linear) analytical description of individual movement, taking into account the fact that the number of revolutions of the particles in the resonance zone is high; study of the self-consistent space charge field, with a view to establishing the conditions necessary for the energy of the ions to be of the order of the energy gained by the electrons in the resonance zone; calculation of the self-consistent HF field in the accelerated plasma, with a view to establishing the conditions for optimum operation of the HF accelerator; the problem of the mirror losses. The experimental results were obtained with various devices constructed for the purpose of verifying the theoretical predictions. With the Circe-Pleiade, where the ionization and acceleration functions have been separated by means of ionization with a Circe device ({lambda} = 3 cm, 300 W), it has been verified the relativistic law of variation of the parallel ion energy as a function of the injected density (existence of a minimum density for the entrainment of ions) and of the applied HF power (TE{sub 111} cavity, 3 GHz, 700 W). With the Circe accelerator ({lambda} =3 cm, P = 2.5kW, CW) it has been verified that, for n{sub plasma} n{sub c} , because of the strong attenuation of the field due to the high index. With the Icare device ({lambda} = 25 cm, P{sub HF} = 1 MW for 100 {mu}s), operating with pre-ionization by laser focalization on a solid D{sub 2} target with an injection density always higher than the cut-off density, accelerated deuteron

  19. Underground nuclear explosions. Geological survey of the cavities; Explosions nucleaires souterraines etude geologique des cavites

    Energy Technology Data Exchange (ETDEWEB)

    Faure, J [Commissariat a l' Energie Atomique, Bruyeres-le-Chatel (France). Centre d' Etudes

    1969-07-01

    A geological survey of underground nuclear explosions makes it possible to determine the main characteristics of the cavity formed. The lower portion is spherical; the same was very likely true of the roof, which collapses in the majority of media with the exception of rock-salt. Its radius, for a given bomb size, can vary by a factor of two according to the type of rock. The lay-out of its contents depends on the characteristics of the solid and liquid products at the moment of the roof collapse; according to the medium involved, mixing of the rubble and the mud-flow occurs (granite) or does not occur (tuff and alluvia). In all media, the average physical properties can be evaluated. (author) [French] L'etude geologique d'explosions nucleaires souterraines permet de determiner les principaux caracteres de la cavite creee. Sa partie inferieure est spherique; il en etait vraisemblablement de meme de sa voute, effondree dans la plupart des milieux a l'exception du sel gemme. Son rayon, a energie d'engin egale, varie selon les roches du simple au double. La disposition de son contenu depend des caracteristiques des produits solides et liquides au moment de la chute du toit; selon le cas, il n'y a pas (tuf et alluvions) ou il y a (granite) melange des eboulis et des laves. Dans tous les milieux, les proprietes physiques moyennes peuvent etre evaluees. (auteur)

  20. The coupling of high-speed high resolution experimental data and LES through data assimilation techniques

    Science.gov (United States)

    Harris, S.; Labahn, J. W.; Frank, J. H.; Ihme, M.

    2017-11-01

    Data assimilation techniques can be integrated with time-resolved numerical simulations to improve predictions of transient phenomena. In this study, optimal interpolation and nudging are employed for assimilating high-speed high-resolution measurements obtained for an inert jet into high-fidelity large-eddy simulations. This experimental data set was chosen as it provides both high spacial and temporal resolution for the three-component velocity field in the shear layer of the jet. Our first objective is to investigate the impact that data assimilation has on the resulting flow field for this inert jet. This is accomplished by determining the region influenced by the data assimilation and corresponding effect on the instantaneous flow structures. The second objective is to determine optimal weightings for two data assimilation techniques. The third objective is to investigate how the frequency at which the data is assimilated affects the overall predictions. Graduate Research Assistant, Department of Mechanical Engineering.

  1. Chemical interactions between the metallic silver aerosols and the iodide compounds in the containment building of a PWR reactor during a serious accident; Interactions chimiques entre les aerosols d'argent metallique et les composes iodes dans l'enceinte de confinement d'un reacteur nucleaire a eau pressurisee en cas d'accident grave

    Energy Technology Data Exchange (ETDEWEB)

    Serra, D.; Saint-Raymond, O.; Zoulalian, A. [Universite Henri Poincare, LERMAB-ENSTIB, 54 - Vandoeuvre-les-Nancy (France); Montanelli, T. [CEA/Cadarache, Inst. de Protection et de Surete Nucleaire, IPSN/DRS/SESHP/LEATS, 13 - Saint-Paul-lez-Durance (France)

    2000-07-01

    During an hypothetical severe accident in a PWR, the iodide fission products can be transferred into the liquid phase of the containment with silver particles (or silver colloid) resulting from the fusion and the vaporization of neutronic control rods. The chemical interactions between the iodide ions and the molecular iodine with the silver particles are studied in an aqueous phase separately and without radiation. The interaction between the iodide ions and silver particles requires a preliminary oxidation step of the silver particles the rate of which depends on the pH, the temperature and the liquid oxygen concentration. A kinetic model including two independent stoichiometries allows to represent correctly the whole experimental runs. At pH = 3, the chemical interactions between molecular iodine and silver particles do not require an oxidation step and a second order kinetic model is able to represent the experimental results considering the operating conditions studied. (authors)

  2. Theoretical and Experimental Methods in Hypersonic Flows (Les Methodes Theoriques et Experimentales pour l’Etude Des Ecoulements Hypersoniques)

    Science.gov (United States)

    1993-04-01

    vibrationicl (fans des tuNZ~rcs tesi pri~sentee. Pour les conditions g~n~iatr-iccs consid~r~es, 1 onisation I es tenoes tie flux die Moude parfait son...lenus figures possibles, deux initialisations du champ valcurs de Y/delta (Y ktant Is distance A Ia peau wont disponibles : et DELTA , I’kpaissenr de...maillage support on calcule Plus de details sont disponibles dans les les distances des nocuds A la peau tres references . prkciskment. Le code N.S

  3. Statistical pulses generator. Application to nuclear instrumentation (1962); Generateur d'impulsions aleatoires. Application a l'instrumentation nucleaire (1962)

    Energy Technology Data Exchange (ETDEWEB)

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

    1962-07-01

    This report describes a random pulses generator adapted to nuclear instrumentation. After a short survey on the statistical nature of electronic signals, the different ways for generating pulses with a Poisson's time-distribution are studied. The final generator built from a gaseous thyratron in a magnetic field is then described. Several tests are indicated : counting-rate stability, Pearson's criterion, distribution of time-intervals. Applications of the generator in 'whole testing' of nuclear instrumentation are then indicated for sealers, dead time measurements, time analyzers. In this application, pulse-height spectrums have been made by Poissonian sampling of a recurrent or random low-frequency signal. (author) [French] Cette etude decrit un generateur d'impulsions aleatoires et ses applications a l'instrumentation nucleaire. Apres un bref rappel sur la nature statistique des signaux en electronique nucleaire, sont passes en revue les principaux moyens d'obtenir des impulsions distribuees en temps suivant une loi de Poisson. Le generateur utilisant un thyratron a gaz dans un champ magnetique est ensuite decrit; diverses methodes de test sont appliquees (stabilite du taux de comptage, criterium de Pearson, spectre des intervalles ds temps). Les applications du generateur a l'electronique nucleaire dans le domaine des 'essais globaux' sont indiques: test des echelles de comptage et mesure des temps morts, test des analyseurs en temps apres division du taux de comptage par une puissance de deux, test des analyseurs multicanaux en amplitude. Pour cette derniere application, on a realise des spectres d'amplitudes suivant une loi connue, par echantillonnage poissonien d'un signal basse frequence recurrent ou aleatoire. (auteur)

  4. Study of some continuous spectra produced by nuclear reactions with light nuclei; Etude de quelques spectres continus produits par reactions nucleaires avec des noyaux legers

    Energy Technology Data Exchange (ETDEWEB)

    Marquez, L

    1966-07-01

    The continuous spectra coming from several nuclear reactions with light nuclei were measured. The spectra can be explained by a two-step reaction mechanism; however, the reactions produced by {sup 6}Li are different. A mechanism was proposed to explain their spectra based on the following assumptions: {sup 6}Li makes a nuclear molecule with the target which subsequently breaks up in such a way that an {alpha} particle comes out with the kinetic energy that it has in the molecule. The calculated spectra and those measured are in good agreement. (author) [French] Nous avons mesure les spectres continus produits dans plusieurs reactions nucleaires avec des noyaux legers. A l'exception des spectres produits par {sup 6}Li, on a trouve qu'on pouvait expliquer ces spectres par le mecanisme des reactions en deux etapes. Nous avons propose un mecanisme pour expliquer les spectres produits par {sup 6}Li. On suppose que {sup 6}Li forme une molecule nucleaire avec la cible qui eclate ensuite de facon telle qu'une particule alpha de la molecule sort avec l'energie cinetique de son mouvement propre dans la molecule. Les spectres calcules avec ces hypotheses et les spectres mesures sont en bon accord. (auteur)

  5. Primary Distributions of Nuclear Charge for Fission-Fragment Masses 132, 134, 136 and 137 from Thermal Fission of U{sup 235}; Repartition Primaire de la Charge Nucleaire pour les Fragments de Masse 132, 134, 136 et 137, Provenant de la Fission de {sup 235}U par Neutrons Thermiques; 041f 0415 0420 0414 ; Distribuciones Primarias de las Cargas Nucleares de los Fragmentos de Masa 132, 134, 136 y 137, Resultantes de la Fision del {sup 235}U por Neutrones Termicos

    Energy Technology Data Exchange (ETDEWEB)

    Konecny, E.; Opower, H.; Guenther, H.; Goebel, H. [Physik-Department der Technischen Hochschule Muenchen, Munich and II. Physikalisches Institut der Justus Liebig-Universitaet Giessen, Federal Republic of Germany (Germany)

    1965-07-15

    the statistical error arising from the transformation from 2{pi}- to 4{pi}-distribution, and for various kinetic energies as parameters, are in preparation. (author) [French] A l'aide d'un spectrometre de masse, on separe avec precision les fragments de la fission thermique de {sup 235}U d'apres leur masse et leur energie cinetique dans la microseconde qui suit la fission. Les fragments separes sont retenus dans une emulsion Ilford G 5 sensible aux particules {beta}, qui est placee dans le plan focal du spectrometre. Les emulsions irradiees sont developpees, dans la mesure du possible, apres un delai relativement long par rapport a la periode la plus longue de la serie radioactive consideree. Les periodes de l'ordre de plusieurs jours ou plus longues encoxe ne sont pas prises en consideration, mais il est facile d'appliquer un facteur de correction approprie. Apres avoir developpe les emulsions, on peut observer au microscope toutes les traces {beta} qui prolongent chacune des traces de fragments de fission. La possibilite d'etablir une correlation entre une trace {beta} et une trace de fragment de fission permet d'evaluer le nombre n(x) de fragments de fission possedant un nombre x de traces {beta}, ce qui indique non seulement la longueur moyenne de la serie mais aussi la distribution des particules {beta}. Le nucleide stable de chaque serie etant connu, la distribution des particules {beta} constitue une image exacte de la repartition primaire des charges nucleaires. Au cours des mesures effectuees jusqu'a present, on n'a en-' registre que les particules {beta} emises dans le demi-angle solide forme par la plaque d'emulsion, mais un calcul statistique simple permet d'evaluer la distribution. 4{pi} voulue. Grace a cette methode, on obtient la distribution des particules 0 a des energies cinetiques determinees proches de l'energie cinetique moyenne de chaque fragment pour les masses 132, 134, 136 et 137. Pour les masses 132 et 134, c'est a la couche de neutrons N

  6. Communications Received from Certain Member States Regarding Guidelines for Transfers of Nuclear-related Dual-use Equipment, Materials, Software and Related Technology; Communications recues de certains Etats Membres concernant les directives applicables aux transferts d'equipements, de matieres et de logiciels a double usage dans le domaine nucleaire, ainsi que de technologies connexes

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2006-04-10

    The Director General of the International Atomic Energy Agency has received Notes Verbales, dated 1 December 2005, from the Resident Representatives to the Agency of Argentina, Australia, Austria, Belarus, Belgium, Brazil, Bulgaria, Canada, Croatia, Czech Republic, Estonia, Finland, France, Germany, Greece, Hungary, Ireland, Italy, Japan, Republic of Korea, Latvia, Lithuania, Luxembourg, Malta, the Netherlands, New Zealand, Poland, Portugal, Slovenia, South Africa, Spain, Sweden, Switzerland, Turkey, Ukraine, the United Kingdom of Great Britain and Northern Ireland and the United States of America, relating to transfers of nuclear-related dual-use equipment, materials, software and related technology [French] Le Directeur general de l'Agence internationale de l'energie atomique a recu des notes verbales datees du 1er decembre 2006 des representants permanents aupres de l'Agence des Etats suivants : Afrique du Sud, Allemagne, Argentine, Australie, Autriche, Belarus, Belgique, Bresil, Bulgarie, Canada, Croatie, Espagne, Estonie, Etats-Unis d'Amerique, Finlande, France, Grece, Hongrie, Irlande, Italie, Japon, Lettonie, Lituanie, Luxembourg, Malte, Nouvelle-Zelande, Pays-Bas, Pologne, Portugal, Republique de Coree, Republique tcheque, Royaume-Uni de Grande-Bretagne et d'Irlande du Nord, Slovenie, Suede, Suisse, Turquie et Ukraine, au sujet des transferts d'equipements, de matieres et de logiciels e double usage dans le domaine nucleaire, ainsi que de technologies connexes.

  7. Dynamic problems of power reactors and analogic devices; Les problemes dynamiques du reacteur de puissance et les machines analogiques

    Energy Technology Data Exchange (ETDEWEB)

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

    1955-07-01

    The raise of the nuclear physics came with heavy mathematical developments. The analogical installations became especially useful for precise calculations of parameters which depend the running of a reactor. They permit between other to study of kinetic problems and especially ''cybernetics'' of nuclear reactors. It doesn't make a doubt that their use will become widespread, not only in the calculations laboratories, in services for servo-mechanisms study, but also in the control panels of the reactors themselves. (M.B.) [French] L'essor de la physique nucleaire s'est accompagne de lourds developpements mathematiques. Les montages analogiques sont devenus particulierement utiles pour les calculs precis des parametres dont depend le fonctionnement d'un reacteur. Elles permettent entre autre l'etude des problemes cinetiques et surtout ''cybernetiques'' des reacteurs nucleaires. Il ne fait pas de doute que leur usage se generalisera, non seulement dans les laboratoires de calculs, les services d'etudes de servomecanismes, mais aussi pres des tableaux de commande des reacteurs eux-memes. (M.B.)

  8. General problems arising from the analogical resolution of the kinetic equations of nuclear reactors (1961); Problemes generaux poses par la resolution analogique des equations cinetiques des reacteurs nucleaires (1961)

    Energy Technology Data Exchange (ETDEWEB)

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

    1961-07-01

    The author reviews precisely the analogical techniques used for the resolution of the kinetic equations of nuclear reactors. Prior to this, he recalls the reasons which oblige physicians and engineers, even today, to use electronic machines in this domain. The author then considers the technological problems posed by the range of values which the various nuclear parameters adopt. In each case, he shows that a compromise is possible allowing an optimum precision. He compares the results to those obtained by arithmetic calculation and uses the examples chosen in a critical analysis of the present possibilities of the two methods of calculation. (author) [French] L'auteur cherche a faire un point aussi exact que possible des techniques analogiques utilisees pour resoudre les equations cinetiques des reacteurs nucleaires. Il rappelle auparavant les raisons pour lesquelles physiciens et ingenieurs sont obliges, encore aujourd'hui, de faire appel aux machines electroniques dans ce domaine. Puis il etudie les problemes technologiques que souleve le champ des valeurs prises par les differents parametres nucleaires. Dans chacun des cas, il montre l'existence d'un compromis qui permet d'atteindre une precision optimum. Il compare les resultats obtenus a ceux provenant de calculateurs arithmetiques et profite des exemples choisis pour faire une analyse critique des possibilites actuelles offertes par les deux modes de calcul. (auteur)

  9. French people and nuclear wastes; Les francais et les dechets nucleaires

    Energy Technology Data Exchange (ETDEWEB)

    D' Iribarne, Ph [Centre National de la Recherche Scientifique (CNRS), 75 - Paris (France)

    2005-07-01

    On March 21, 2005, the French minister of industry gave to the author of this document, the mission to shade a sociological light on the radioactive wastes perception by French people. The objective of this study was to supply an additional information before the laying down in 2006 of the decisions about the management of high-level and long-lived radioactive wastes. This inquiry, carried out between April 2004 and March 2005, stresses on the knowledge and doubts of the questioned people, on the vision they have of radioactive wastes and of their hazards, and on their opinion about the actors in concern (experts, nuclear companies, government, anti-nuclear groups, public). The last two parts of the report consider the different ways of waste management under study today, and the differences between the opinion of people living close to the Bure site and the opinion of people living in other regions. (J.S.)

  10. Nuclear physics: large instruments and challenges; La physique nucleaire: les grands instruments et les defis

    Energy Technology Data Exchange (ETDEWEB)

    Harar, S. [CEA Centre d`Etudes Nucleaires de Saclay, 91 - Gif-sur-Yvette (France). Direction des Sciences de la Matiere

    1997-12-31

    Researches on nuclear physics and atomic nucleus can be divided into three periods of time at the CEA: from 1950 to 1970, the characteristics of atomic nucleus structure are measured and accelerators are used; in the early 70`s, heavy ion physics, with the Ganil accelerator, allows for the study of large perturbations in nuclei, while the meson physics study the nucleon interactions using the Saclay 700 MeV electron linear accelerator. In the early 90`s, the radioactive beams provided by the SPIRAL/Ganil device allows for the study of the nucleon internal structure, the quarks, and their effects while their deconfinement is studied by the means of the relativistic heavy ions provided by the LHC accelerator

  11. Factors and uncertainties in the profitability of using nuclear energy in desalination of water; Facteurs et incertitudes de la rentabilite du recours a l'energie nucleaire dans le dessalement des eaux

    Energy Technology Data Exchange (ETDEWEB)

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

    1969-07-01

    One of the economic advantages of nuclear energy consists of the small proportional element in its cost structure. Economies of scale favour the nuclear station as compared with the conventional thermal one, and when the demand for electricity and heat, in particular for desalination, are sufficient, nuclear energy may, subject to certain conditions, prove advantageous. The object of this paper is to discuss the validity of the conclusions reached according to the hypotheses adopted. In the first part, the different kind of uncertainties connected with technical, economic and financial data (the various transmission coefficients, the life of equipment according to the choice of materials, changes in prices, the form of price functions and interest rates), and with the various constraints, are examined and discussed. In the second part the uncertainties connected with the method of optimisation used and the criterion of selection adopted are examined and discussed. It is shown thereby that it is usually extremely difficult to assume absolutely the competitiveness, or conversely the non-competitiveness, of using nuclear energy in the desalination of water, and that a large number of aspects have to be carefully examined. (author) [French] On sait que l'un des avantages economiques de l'energie nucleaire reside dans la faible part proportionnelle dans la structure de son cout. Les economies d'echelle favorisent le nucleaire par rapport au thermique classique, et lorsque les demandes d'electricite et de chaleur, notamment pour le dessalement, sont suffisantes on peut envisager favorablement, sous certaines hypotheses, le recours a l'energie nucleaire. L'objet de cette communication est de discuter la validite des conclusions auxquelles on parvient selon les hypotheses envisagees. Dans une premiere partie, on etudie et on discute les differentes sortes d'incertitudes, liees aux donnees techniques, economiques et financieres (les divers coefficients de transmission, les

  12. General phenomenology of underground nuclear explosions; Phenomenologie generale des explosions nucleaires souterraines

    Energy Technology Data Exchange (ETDEWEB)

    Derlich, S; Supiot, F [Commissariat a l' Energie Atomique, Bruyeres-le-Chatel (France). Centre d' Etudes

    1969-07-01

    An essentially qualitatively description is given of the phenomena related to underground nuclear explosions (explosion of a single unit, of several units in line, and simultaneous explosions). In the first chapter are described the phenomena which are common to contained explosions and to explosions forming craters (formation and propagation of a shock-wave causing the vaporization, the fusion and the fracturing of the medium). The second chapter describes the phenomena related to contained explosions (formation of a cavity with a chimney). The third chapter is devoted to the phenomenology of test explosions which form a crater; it describes in particular the mechanism of formation and the different types of craters as a function of the depth of the explosion and of the nature of the ground. The aerial phenomena connected with explosions which form a crater: shock wave in the air and focussing at a large distance, and dust clouds, are also dealt with. (authors) [French] On donne une description essentiellement qualitative des phenomenes lies aux explosions nucleaires souterraines (explosion d'un seul engin, d'engins en ligne et explosions simultanees). Dans un premier chapitre sont decrits les phenomenes communs aux explosions contenues et aux explosions formant un cratere (formation et propagation d'une onde de choc provoquant la vaporisation, la fusion et la fracturation du milieu). Le deuxieme chapitre decrit les phenomenes lies aux tirs contenus (formation d'une cavite et d'une cheminee). Le troisieme chapitre est consacre a la phenomenologie des tirs formant un cratere et decrit notamment le mecanisme de formation et les differents types de crateres en fonction de la profondeur d'explosion et de la nature du terrain. Les phenomenes aeriens lies aux explosions formant un cratere: onde de pression aerienne et focalisation a grande distance, nuages de poussieres, sont egalement abordes. (auteurs)

  13. Piles used for the nuclear control of materials; Empilements pour le controle nucleaire des materiaux

    Energy Technology Data Exchange (ETDEWEB)

    Raievski, V; Sautiez, B; Bailly du Bois, B; Tretiakoff, O; Thome, P; Vidal, R; Koppel Martelly, J [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1958-07-01

    The devices which make it possible to check on the nuclear qualities of the materials used in reactor construction are described. These verifications bear on substantial masses of materials, following the last stage of their machining. The components found in all these are a graphite pile into which the material to be investigated is inserted, a source of neutrons made up of an Ra-Be system, and a proportional BF{sub 3} counter. The devices described here bear on checking graphite, beryllium oxide and uranium absorption, as well as on a verification of the {sup 235}U content of fuel elements. (author)Fren. [French] On decrit des dispositifs permettant de controler les qualites nucleaires de materiaux utilises dans la construction des piles. Ce controle s'effectue sur des masses importantes de materiaux apres la phase finale d'usinage. Ces dispositifs ont en commun un empilement de graphite recevant le materiau a etudier, une source de neutrons de Ra-Be et un compteur proportionnel a BF{sub 3}. Les dispositifs decrits concernent le controle de l'absorption du graphite, de la glucine et de l'uranium, ainsi que le controle de la teneur en {sup 235}U des elements de combustion. (auteur)

  14. Study of the chimney produced by an underground nuclear explosion; Etude de la cheminee creee par une explosion nucleaire souterraine

    Energy Technology Data Exchange (ETDEWEB)

    Derlich, S [Commissariat a l' Energie Atomique, Bruyeres-le-Chatel (France). Centre d' Etudes

    1969-07-01

    Underground nuclear explosions lead to the formation of a cavity which is roughly of spherical shape. The roof of this cavity is unstable and collapses in most cases, leading to the formation of a chimney. The height and the diameter depend on the energy of the charge and on the nature of the surroundings. The chronology of the various stages can be determined by seismic observations. The interior of the chimney is filled, either partially or completely, with rubble earth. This phenomenon is of great importance as far as the use of nuclear explosions for industrial applications is concerned. (author) [French] Les explosions nucleaires souterraines creent une cavite de forme grossierement spherique. La voute de cette cavite est instable et s'effondre dans la plupart des cas, donnant lieu a la formation d'une cheminee. La hauteur et le diametre sont fonction de l'energie du tir et de la nature du milieu. La chronologie des evenements peut etre determinee par des observations seismiques. L'interieur des cheminees est occupe, en partie ou en totalite, par des eboulis. Ce phenomene presente un grand interet pour l'utilisation des explosions nucleaires a des fins industrielles. (auteur)

  15. Nuclear purity and the production of uranium (1962); La purete nucleaire et la fabrication de l'uranium (1962)

    Energy Technology Data Exchange (ETDEWEB)

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

    1962-07-01

    When the production of 'nuclear grade' uranium is dealt with, it is difficult, the author of this study points out, to separate its chemical, technical, and economical bearings. While recalling the evolution of chemical processes in various countries and describing the technic of uranium manufacture in the plant of the French 'Commissariat a l'Energie Atomique' at Le Bouchet, the author outlines the effect of economical contingencies on the problems the chemists and engineer are faced with. The question of cost price is also considered here with particular attention. (author) [French] Lorsqu'il s'agit de la production d'uranium de 'qualite nucleaire', il est difficile, souligne l'auteur de cette etude, de separer les aspects chimique, technique et economique. Aussi, en retracant l'evolution des procedes chimiques dans divers pays et decrivant les techniques de fabrication de l'uranium a l'usine du Bouchet du Commissariat a l'Energie Atomique, l'auteur ne manque-t-il pas de rappeler les incidences de la conjoncture economique sur les problemes posees au chimiste et a l'ingenieur. La question du prix de revient, egalement, est traitee ici avec une attention particuliere. (auteur)

  16. Status of computational and experimental correlations for Los Alamos fast-neutron critical assemblies; Correlation entre les calculs et les experiences sur les ensembles critiques a neutrons rapides de Los Alamos; Sostoyanie vychislitel'nykh i ehksperimental'nykh korrelyatsij dlya Los-Alamosskoj kriticheskoj sistemy na bystrykh nejtronakh; Conjuntos criticos de neutrones rapidos de Los Alamos; correlacion entre resultados calculados y experimentales

    Energy Technology Data Exchange (ETDEWEB)

    Hansen, G E [Los Alamos Scientific Laboratory, University of California, Los Alamos, NM (United States)

    1962-03-15

    New assemblies and improved measuring techniques call for periodic review of the status of computation vs. experiment. It is appropriate to emphasize neutron-spectral characterizations because of the particularly elusive problems associated with absolute spectral-index measurement and the need for checks of computation beyond simple critical size. The ever-improving spectral-index measurements in conjunction with increasing precision, both of microscopic data for detector and assembly materials and of computational techniques, produce a gradual clarification of the characteristics of a family of fast-neutron critical assemblies. This family now includes unreflected and thick-uranium-reflected U{sup 233} in spherical geometry. Direct correlations among the experimental data will be presented to indicate the a priori possibilities for successful correlations with computation. Sensitivity of computed spectra and critical sizes to neutron-transport models (transport and linear approximations ) and arithmetic approximations (finite angular segmentations and multi-group representations) will be presented for several typical assemblies to help establish the necessary computational detail. Comparisons between experiment and prediction will include, in addition to spectral indices and critical sizes, neutron lifetimes and delayed-neutron fractions. (author) [French] Du fait de la mise en service de nouveaux reacteurs et de l'amelioration des methodes de mesure, il est necessaire de faire periodiquement la correlation des experiences et des calculs. Il est utile d'insister sur les caracterisations de spectres de neutrons a cause des problemes particulieremen t delicats que pose la mesure absolue de l'indice spectral et de la necessite de verifier les calculs au-dela des simples dimensions critiques. Les mesures constamment ameliorees de l'indice spectral, associees a la precision croissante des donnees microscopiques relatives aux materiaux utilises dans les detecteurs et

  17. Contribution to the study of the evolution of radiation induced He in Be O; Etudes sur l'evolution de l'helium produit par reactions nucleaires dans l'oxyde de beryllium

    Energy Technology Data Exchange (ETDEWEB)

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

    1966-11-15

    The purpose of this work in-pile investigation of He formed by (n, 2n) and (n, {alpha}) nuclear reactions, released from irradiated BeO, in the temperature range 1000 - 1350 deg. C. The experimental results show that, for an instantaneous neutron fast flux of 10{sup 13} n cm{sup -2} sec{sup -1}, an equilibrium is attempted, after several days, for a part lower than 20 per cent of the quantity of He formed, theoretically calculated from the neutron cross sections of nuclear reactions, and from the analytical form of the neutron fast flux, releases from the solid. The validity of the values of calculated helium and the gas chromatographic analytical method are also verified by dissolution of the BeO pellets in cryolite. A new fast neutron flux measuring method may be so defined. The discussion of the experimental results enables to establish that the processus of He release is characterized by two phenomena: the first one which controls the release of He atoms out of the solid and the second which reveals a capture processus, connected to the irradiation and probably due to the vacancies induced in the lattice. (author) [French] On etudie en pile le degagement de l'helium forme par reactions nucleaires (n, 2 n) et (n, {alpha}) dans l'oxyde de beryllium irradie entre 1000 et 1350 deg. C. Les resultats experimentaux montrant que, pour un flux rapide instantane de 10{sup 13} n{sub r} cm{sup -2} s{sup -1}, on aboutit, au bout de quelques jours, a un etat d'equilibre pour lequel une partie, inferieure a 20 pour cent de la quantite d'helium forme, calculee theoriquement a partir des sections efficaces des reactions nucleaires et de la forme analytique du flux rapide, s'echappe du solide. On verifie egalement par dissolution des echantillons de BeO dans la cryolithe la validite du calcul de l'helium et de la methode de dosage par chromatographie en phase gazeuse. On peut ainsi definir une methode nouvelle de mesure des flux rapides. La discussion des resultats experimentaux

  18. Contribution to the study of the evolution of radiation induced He in Be O; Etudes sur l'evolution de l'helium produit par reactions nucleaires dans l'oxyde de beryllium

    Energy Technology Data Exchange (ETDEWEB)

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

    1966-11-15

    The purpose of this work in-pile investigation of He formed by (n, 2n) and (n, {alpha}) nuclear reactions, released from irradiated BeO, in the temperature range 1000 - 1350 deg. C. The experimental results show that, for an instantaneous neutron fast flux of 10{sup 13} n cm{sup -2} sec{sup -1}, an equilibrium is attempted, after several days, for a part lower than 20 per cent of the quantity of He formed, theoretically calculated from the neutron cross sections of nuclear reactions, and from the analytical form of the neutron fast flux, releases from the solid. The validity of the values of calculated helium and the gas chromatographic analytical method are also verified by dissolution of the BeO pellets in cryolite. A new fast neutron flux measuring method may be so defined. The discussion of the experimental results enables to establish that the processus of He release is characterized by two phenomena: the first one which controls the release of He atoms out of the solid and the second which reveals a capture processus, connected to the irradiation and probably due to the vacancies induced in the lattice. (author) [French] On etudie en pile le degagement de l'helium forme par reactions nucleaires (n, 2 n) et (n, {alpha}) dans l'oxyde de beryllium irradie entre 1000 et 1350 deg. C. Les resultats experimentaux montrant que, pour un flux rapide instantane de 10{sup 13} n{sub r} cm{sup -2} s{sup -1}, on aboutit, au bout de quelques jours, a un etat d'equilibre pour lequel une partie, inferieure a 20 pour cent de la quantite d'helium forme, calculee theoriquement a partir des sections efficaces des reactions nucleaires et de la forme analytique du flux rapide, s'echappe du solide. On verifie egalement par dissolution des echantillons de BeO dans la cryolithe la validite du calcul de l'helium et de la methode de dosage par chromatographie en phase gazeuse. On peut ainsi definir une methode nouvelle de mesure des flux rapides. La

  19. Coupling of a real time computer to nuclear detectors systems; Couplage d'un calculateur en temps reel a un ensemble experimental de detection

    Energy Technology Data Exchange (ETDEWEB)

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

    1967-06-01

    Electronic computers are now included in nuclear physics experiment systems. This corresponds to a general trend to replace conventional multichannel analyzers by on line, real time, computers. An one line computer performing nuclear data acquisition and storage, offers the advantage of reduction and calculation routines in real time. This advantage becomes a need when the number of experimental parameters increase. At the Saclay variable energy cyclotron we have connected a C 90-10 computer of C.I.I. We describe the input/output hardware features. In order to establish a dialogue with physicists, we have built a main display unit able to control many display consoles at different points: we describe them as well as some utility routines. (author) [French] Les experiences de physique nucleaire font appel, de plus en plus, a des calculateurs electroniques. Ceux-ci se substituent alors aux analyseurs multicanaux traditionnels. Un calculateur en ligne assurant l'acquisition et le stockage des donnees experimentales, presente l'avantage de pouvoir executer, en temps reel, des programmes simples de calcul et de reduction. Nous montrons la necessite de prise en charge, par un calculateur, des experiences de physique nucleaire ou le nombre des parametres experimentaux devient important. Au cyclotron a energie variable de Saclay, la solution retenue est l'emploi d'un calculateur C 90-10 de la C.I.I. Nous decrivons les interfaces necessaires au couplage. Afin d'assurer un dialogue avec les physiciens, un systeme de visualisation est realise; nous le decrivons ainsi que quelques programmes types d'utilisation de l'ensemble du systeme. (auteur)

  20. The pulsed neutron method applied to the determination of the nuclear constants of graphite (1961); La methode des neutrons pulses appliquee a la determination des constantes nucleaires du graphite (1961)

    Energy Technology Data Exchange (ETDEWEB)

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

    1961-07-01

    A method for determining the nuclear constants {sigma}{sub a} and {lambda}{sub t} of a moderator is described. The disappearance of a burst of neutrons introduced into a finite medium is studied as a function of time. This decrease in the thermal neutron density is the product of two exponentials; one representing the absorption, the other the leakage. By varying one or other of these factors, the constants of the factor left unvaried can be determined, and from this the nuclear constant values are deduced. (author) [French] On decrit une methode permettant de determiner les constantes nucleaires {sigma}{sub a} et {lambda}{sub t} d'un moderateur. On etudie la decroissance dans le temps d'une bouffee de neutrons introduite dans un milieu fini. Cette decroissance de la densite en neutrons thermiques est le produit de deux exponentielles; l'une represente l'absorption, l'autre les fuites. Par variation de l'un ou l'autre de ces facteurs, on determine les constantes du facteur laisse invariant dont on deduit les valeurs des constantes nucleaires. (auteur)

  1. Experimental investigation of the effects of aqueous species on the dissolution kinetics of R7T7 glass; Etude experimentale de l`influence d`especes aqueuses sur la cinetique de dissolution du verre nucleaire R7T7

    Energy Technology Data Exchange (ETDEWEB)

    Gin, S

    1994-10-01

    This contribution to the study of aqueous corrosion of the French ``R7T7`` reference nuclear containment glass includes a bibliographic survey of prior investigations, highlighting the problems encountered in interpreting the interactions in systems containing clay materials in contact with the glass. An experimental methodology is proposed to investigate the effects of inorganic aqueous species separately from those of a few organic acids on the dissolution mechanisms and kinetics of R7T7 glass at 90 deg. C. The experimental results discussed support the idea that several glass network forming elements may have a kinetically limiting role. The most likely hypothesis to account for the absence of saturation conditions with respect to the glass in certain clay media involves the formation of complexes with kinetically limiting metallic elements such as aluminum released by glass corrosion. This work contributes to a better understanding of the basic mechanisms of nuclear glass dissolution in a geological repository environment. It facilitates the interpretation of glass alteration studies in realistic or actual solutions and may contribute to specifying near field chemical barriers in the form of additives (amorphous silica, aluminum hydroxides or phosphates) around the glass disposal package to enhance the stability of the glass matrix. (author). 148 refs., 40 figs., 32 tabs., 1 append.

  2. Modul.LES: a multi-compartment, multi-organism aquatic life support system as experimental platform for research in ∆g

    Science.gov (United States)

    Hilbig, Reinhard; Anken, Ralf; Grimm, Dennis

    In view of space exploration and long-term satellite missions, a new generation of multi-modular, multi-organism bioregenerative life support system with different experimental units (Modul.LES) is planned, and subunits are under construction. Modul.LES will be managed via telemetry and remote control and therefore is a fully automated experimental platform for different kinds of investigations. After several forerunner projects like AquaCells (2005), C.E.B.A.S. (1998, 2003) or Aquahab (OHB-System AG the Oreochromis Mossambicus Eu-glena Gracilis Aquatic Habitat (OmegaHab) was successfully flown in 2007 in course of the FOTON-M3 Mission. It was a 3 chamber controlled life support system (CLSS), compris-ing a bioreactor with the green algae Euglena gracilis, a fish chamber with larval cichlid fish Oreochromis mossambicus and a filter chamber with biodegrading bacteria. The sensory super-vision of housekeeping management was registered and controlled by telemetry. Additionally, all scientific data and videos of the organisms aboard were stored and sequentially transmitted to relay stations. Based on the effective performance of OmegaHab, this system was chosen for a reflight on Bion-M1 in 2012. As Bion-M1 is a long term mission (appr. 4 weeks), this CLSS (OmegaHab-XP) has to be redesigned and refurbished with enhanced performance. The number of chambers has been increased from 3 to 4: an algae bioreactor, a fish tank for adult and larval fish (hatchery inserted), a nutrition chamber with higher plants and crustaceans and a filter chamber. The OmegaHab-XP is a full automated system with an extended satellite downlink for video monitoring and housekeeping data acquisition, but no uplink for remote control. OmegaHab-XP provides numerous physical and chemical parameters which will be monitored regarding the state of the biological processes and thus enables the automated con-trol aboard. Besides the two basic parameters oxygen content and temperature, products of the

  3. The 1989 annual report of the Institut de Physique Nucleaire-Orsay

    International Nuclear Information System (INIS)

    1989-01-01

    The activity report of the Institut de Physique Nucleaire (Orsay-France) from 1 Sep 1988 to 1 Aug 1989 is presented. Theoretical and experimental investigations were carried out in the following fields: light and medium exotic nuclei, on line spectroscopy, discrete high spin states, new radioactivities, thermal fission, detection systems, giant resonances, high excitation energy structure, reaction mechanisms at energies below 10 MeV/u and at 200 MeV/u and their evolution between 10 and 100 MeV/u, meson production, transfer reactions, spin modes in nuclei, dibaryonic resonances, inelastic scattering of polarized protons. Research programs in the field of radiochemistry and relating to inter-disciplinary fields are included. The activities involving teaching, the lists of publications conferences, seminars and theses are presented [fr

  4. Radioelements: their detection and measurement; Les radioelements: detection et mesure

    Energy Technology Data Exchange (ETDEWEB)

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

    1960-07-01

    A brief review of the properties of nuclear radiations is followed by a description of the basic techniques used for their detection: autoradiography, methods using the ionisation of gases (ionisation chambers, proportional counters, Geiger-Muller counters), scintillation techniques. The principles of the different methods of measurement are explained, whether they concern the activity or the energy absorbed (dosimetry). This is followed by a description of the basic techniques (4 {pi} counter, defined solid angle, {beta}-{gamma} coincidences). (author) [French] Apres un bref rappel des proprietes des rayonnements nucleaires, on decrit les techniques fondamentales employees pour leur detection: autoradiographie, procedes utilisant l'ionisation des gaz (chambres d'ionisation, compteurs proportionnels, compteurs de Geiger-Muller), technique des scintillations. On expose le principe des differentes methodes de mesure concernant soit l'activite, soit l'energie absorbee (dosimetrie). Les techniques fondamentales (compteur 4 {pi}, angle solide defini, coincidences {beta}-{gamma}) sont ensuite decrites. (auteur)

  5. Radioelements: their detection and measurement; Les radioelements: detection et mesure

    Energy Technology Data Exchange (ETDEWEB)

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

    1960-07-01

    A brief review of the properties of nuclear radiations is followed by a description of the basic techniques used for their detection: autoradiography, methods using the ionisation of gases (ionisation chambers, proportional counters, Geiger-Muller counters), scintillation techniques. The principles of the different methods of measurement are explained, whether they concern the activity or the energy absorbed (dosimetry). This is followed by a description of the basic techniques (4 {pi} counter, defined solid angle, {beta}-{gamma} coincidences). (author) [French] Apres un bref rappel des proprietes des rayonnements nucleaires, on decrit les techniques fondamentales employees pour leur detection: autoradiographie, procedes utilisant l'ionisation des gaz (chambres d'ionisation, compteurs proportionnels, compteurs de Geiger-Muller), technique des scintillations. On expose le principe des differentes methodes de mesure concernant soit l'activite, soit l'energie absorbee (dosimetrie). Les techniques fondamentales (compteur 4 {pi}, angle solide defini, coincidences {beta}-{gamma}) sont ensuite decrites. (auteur)

  6. Production of nuclear graphite in France; Production de graphite nucleaire en France

    Energy Technology Data Exchange (ETDEWEB)

    Legendre, P; Mondet, L [Societe Pechiney, 74 - Chedde (France); Arragon, Ph; Cornuault, P; Gueron, J; Hering, H [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1955-07-01

    The graphite intended for the construction of the reactors is obtained by the usual process: confection of a cake from coke of oil and tar, cooked (in a electric oven) then the product of cook is graphitized, also by electric heating. The use of the air transportation and the control of conditions cooking and graphitization have permitted to increase the nuclear graphite production as well as to better control their physical and mechanical properties and to reduce to the minimum the unwanted stains. (M.B.) [French] Le graphite destine a la construction des reacteurs est obtenu par le procede usuel: confection d'une pate a partir de coke de petrole et de brai, cuisson de cette pate (au four electrique) puis graphitation du produit cuit, egalement par chauffage electrique. L'usage du transport pneumatique et le controle des conditions cuisson et de graphitation ont permit d'augmenter la production de graphite nucleaire ainsi que de mieux controler ses proprietes physiques et mecaniques et de reduire au minimum les souillures accidentelles. (M.B.)

  7. Major accident analyses for experimental zero-power fast reactor assemblies; Analyse des accidents graves pouvant survenir dans les reacteurs experimentaux a neutrons rapides de puissance zero; Analiz krupnoj avarii dlya ehksperimental'ny kh reaktornykh ustanovok nulevoj moshchnosti na bystrykh nejtronakh; Analisis de los accidentes graves que pueden producirse en los reactores experimentales rapidos de potencia cero

    Energy Technology Data Exchange (ETDEWEB)

    Fischer, G.; Barts, E. W.; Kapil, S.; Tomabechi, K. [Argonne National Laboratory, Argonne, IL (United States)

    1962-03-15

    systems with the very soft neutron-energy spectra characteristic of large oxide power breeders. (author) [French] Les auteurs ont etudie la possibilite, le mecanisme et les consequences de la fusion et autres accidents nucleaires graves dans les reacteurs experimentaux a neutrons rapides de puissance zero, du type ZPR-III, a coeur divise. Cette etude a ete completee par une evaluation de l'importance de l'effet Doppler sur un grand nombre de reacteurs de ce type. Les auteurs demontrent qu'il est fort peu probable qu'une fusion se produise, du fait que la conjonction des circonstances qui pourraient la provoquer est difficilement realisable. L'expose du mecanisme de fusion est suivi de l'analyse des resultats de calculs couples neutronique-hydrodynamiqu e relatifs a deux reacteurs de puissance zero. On a choisi pour cette etude un coeur de 1200 l, qui correspond a un reacteur relativement grand a coeur normal. L'etude a egalement porte sur un coeur plus petit ayant un coefficient cavitaire plus important, qui pourrait presenter un plus grand danger. Chaque systeme a eu un comportement en fonction du temps tout a fait different. Si un accident grave survient dans un reacteur de puissance zero, les atomes de {sup 235}U, isoles dans les plaques d'uranium enrichi, s'echauffen t tres rapidement tandis que le reste du coeur demeure pratiquement froid; il y a ainsi formation d'un gaz du {sup 235}U qui donne lieu a la pression de rupture. Les auteurs expliquent l'adaptation qu'ils ont faite du code AX-I de neutronique-hydrodynamiqu e pour l'appliquer a un gaz de Van der Waals. Une autre modification importante de l'equation d'etat utilisee dans ce code consiste a employer une equation du type Mie-Grueneisen, derivee de la theorie de l'etat solide. Cette modification permet d'evaluer de facon plus satis- faisante le terme de pression pour les coeurs de composition variable. Du fait que les plaques en uranium fortement enrichi d'un reacteur de puissance zero s'echauffent plus

  8. Methode d’Identification des Forces Aerodynamiques Instationnaires sur les Essais en Vol, Validation Experimentale (Method of Mathematical Identification of Unsteady Airloads From Flight Measurements, Experimental Validation)

    Science.gov (United States)

    2000-05-01

    gage en vol de rdponses de jauges de contraintes en responses in maneuver, illustrated by an example manoeuvre, illustrd par un exemple issu de la coming...sous ddrapage, ... , braquages gouvernes,..) la forme: -Les mesures sont directement les rkponses de - minimiser Z = Q(k - Xj tb) 2 jauges de...3, la rdponse - les facteurs de ponddration des mesures, fli ou incidence de l’avion, la rdponse de la jauge plus ou momns subjectifs, sont remplacds

  9. LES and experimental studies of cold and reacting flow in a swirled partially remixed burner with and without fuel modulation

    NARCIS (Netherlands)

    Sengissen, A.X.; van Kampen, J.F.; Huls, R.A.; Stoffels, Genie G.M.; Kok, Jacobus B.W.; Poinsot, T.J.

    2007-01-01

    In devices where air and fuel are injected separately, combustion processes are influenced by oscillations of the air flow rate but may also be sensitive to fluctuations of the fuel flow rate entering the chamber. This paper describes a joint experimental and numerical study of the mechanisms

  10. The turbulent viscosity models and their experimental validation; Les modeles de viscosite turbulente et leur validation experimentale

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-12-31

    This workshop on turbulent viscosity models and on their experimental validation was organized by the `convection` section of the French society of thermal engineers. From the 9 papers presented during this workshop, 8 deal with the modeling of turbulent flows inside combustion chambers, turbo-machineries or in other energy-related applications, and have been selected for ETDE. (J.S.)

  11. Investigation of heat transfer and flow using ribs within gas turbine blade cooling passage: Experimental and hybrid LES/RANS modeling

    Science.gov (United States)

    Kumar, Sourabh

    Gas turbines are extensively used for aircraft propulsion, land based power generation and various industrial applications. Developments in innovative gas turbine cooling technology enhance the efficiency and power output, with an increase in turbine rotor inlet temperatures. These advancements of turbine cooling have allowed engine design to exceed normal material temperature limits. For internal cooling design, techniques for heat extraction from the surfaces exposed to hot stream are based on the increase of heat transfer areas and on promotion of turbulence of the cooling flow. In this study, it is obtained by casting repeated continuous V and broken V shaped ribs on one side of the two pass square channel into the core of blade. Despite extensive research on ribs, only few papers have validated the numerical data with experimental results in two pass channel. In the present study, detailed experimental investigation is carried out for two pass square channels with 180° turn. Detailed heat transfer distribution occurring in the ribbed passage is reported for steady state experiment. Four different combinations of 60° and Broken 60° V ribs in channel are considered. Thermocouples are used to obtain the temperature on the channel surface and local heat transfer coefficients are obtained for various Reynolds numbers, within the turbulent flow regime. Area averaged data are calculated in order to compare the overall performance of the tested ribbed surface and to evaluate the degree of heat transfer enhancement induced by the ribs with. Flow within the channels is characterized by heat transfer enhancing ribs, bends, rotation and buoyancy effects. Computational Fluid Dynamics (CFD) simulations were carried out for the same geometries using different turbulence models such as k-o Shear stress transport (SST) and Reynolds stress model (RSM). These CFD simulations were based on advanced computing in order to improve the accuracy of three dimensional metal

  12. Irradiation and development of the nuclear emulsions exposed to intense fluxes of thermal neutrons with {gamma} rays; Irradiation et developpement des emulsions nucleaires exposees a des flux intenses de neutrons thermiques, accompagnes de rayons {gamma}

    Energy Technology Data Exchange (ETDEWEB)

    Faraggi, H; Bonnet, A; Cohen, J [Commissariat a l' Energie Atomique, Lab. du Fort de Chatillon, Fontenay-aux-Roses (France). Centre d' Etudes Nucleaires

    1952-07-01

    The thermal neutron fluxes provided by nuclear reactors permit the survey of relatively rare phenomenons, and dosage of very weak quantities of some elements. One of the most favorable detection technique are constituted by the use of the nuclear emulsions. one can mention: - the dosage of uranium by counting in the emulsion the number of traces due to fission fragments after irradiation. - The dosage of the lithium and the boron as trace amounts with the help of nuclear reactions (n, {alpha}) and thermal neutrons. - The research of reactions (n, {alpha}) or (n, p) of very weak cross section for middle or heavy elements. These different applications require however important neutrons fluxes. It had therefore obliged us to search for the most favorable irradiation and development of the emulsions conditions, to get the best visibility of the trajectories and decrease the phenomena of fog on the emulsion, which prevents any observation. (M.B.) [French] Les flux de neutrons thermiques fournis par les reacteurs nucleaires permettent l'etude de phenomenes relativement rares, et le dosage de tres faibles quantites de certains elements. Un des moyens de detection les plus favorables est constitue par l'utilisation des emulsions nucleaires. on peut citer: - le dosage de l'uranium par comptage dans l'emulsion du nombre de traces dues aux fragments de fission apres irradiation. - Le dosage du lithium et du bore a l'etat de traces a l'aide des reactions (n, {alpha}) sous l'action des neutrons thermiques. - La recherche de reactions (n,{alpha}) ou (n,p) de tres faible section efficace pour des elements moyens ou lourds. Ces differentes applications necessite cependant des flux de neutrons important. On a donc ete amene a rechercher les conditions les plus favorables d'irradiation et de developpement des emulsions, de maniere a obtenir la meilleure visibilite des trajectoires et diminuer les phenomenes de voile de l'emulsion, qui empeche toute observation. (M.B.)

  13. Les aciers inoxydables dans les fixations

    CERN Document Server

    CETIM

    2010-01-01

    Cet ouvrage, qui fait la synthèse de plusieurs travaux menés par le Cetim, propose une vue d'ensemble sur les aciers inoxydables utilisés pour les fixations. Au sommaire : les normes EN, ISO et ATSM qui s'y rapportent , les désignations symboliques , les nuances et caractéristiques mécaniques , les différentes formes de corrosion, les méthodes pour les détecter , les règles du métier , les mises en oeuvre. L'ouvrage comprend plusieurs fiches matériaux et des tableaux qui présentent les équivalences entre les désignations.

  14. Nuclear developments at the international inter govern mental level (1961); Developpements nucleaires sur le plan international intergouvernemental (1961)

    Energy Technology Data Exchange (ETDEWEB)

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

    1961-07-01

    The United Nations organisation and nuclear energy rose simultaneously, in 1945, to occupy an important place in the public eye. The spiritual succession of the League of Nations which had foundered during the war was taken up by the new organisation which sought to implant its political ideal in a more tangible reality, so that it might thereby be inspired by concrete and substantial objectives. This is one of the reasons for the existence of the dozen specialized agencies created by the family of the United Nations and dealing with Health, Culture, Agriculture, Finance, etc. Nuclear energy is one of these techniques. Becoming suddenly an important power factor and exploiting for itself the prestige of Science, it became the favorite domain for the growth of this new spirit, as much in its universal form in 1945 as in its more regional form which it was later to adopt. The achievements are numerous and of varying importance; they deserve te be studied carefully. (author) [French] L'organisation des Nations Unies et le nucleaire ont ete places simultanement, en 1945, au premier plan de la scene mondiale. La Societe des Nations ayant sombre pendant la guerre, son heritage spirituel fut recueilli par la nouvelle organisation qui chercha a enraciner son ideal politique dans une realite plus materielle, de facon a y puiser une nourriture concrete et substantielle. C'est une des raisons d'existence de la douzaine d'institutions specialisees gravitant dans la famille des Nations Unies et s'occupant de Sante, de Culture, d'Agriculture, de Finances, etc. Le nucleaire est l'une de ces techniques. Devenu soudainement un facteur primordial de puissance, Cristallisant a son benefice le prestige de la Science, c'etait un terrain de predilection pour le developpement du nouvel esprit, aussi bien sous la forme universelle de 1945, que sous les formes regionales qui ont vu le jour ensuite. Les travaux realises que nombreux, d'importance tres inegale. Ils meritent qu'on les examine

  15. Nuclear developments at the international inter govern mental level (1961); Developpements nucleaires sur le plan international intergouvernemental (1961)

    Energy Technology Data Exchange (ETDEWEB)

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

    1961-07-01

    The United Nations organisation and nuclear energy rose simultaneously, in 1945, to occupy an important place in the public eye. The spiritual succession of the League of Nations which had foundered during the war was taken up by the new organisation which sought to implant its political ideal in a more tangible reality, so that it might thereby be inspired by concrete and substantial objectives. This is one of the reasons for the existence of the dozen specialized agencies created by the family of the United Nations and dealing with Health, Culture, Agriculture, Finance, etc. Nuclear energy is one of these techniques. Becoming suddenly an important power factor and exploiting for itself the prestige of Science, it became the favorite domain for the growth of this new spirit, as much in its universal form in 1945 as in its more regional form which it was later to adopt. The achievements are numerous and of varying importance; they deserve te be studied carefully. (author) [French] L'organisation des Nations Unies et le nucleaire ont ete places simultanement, en 1945, au premier plan de la scene mondiale. La Societe des Nations ayant sombre pendant la guerre, son heritage spirituel fut recueilli par la nouvelle organisation qui chercha a enraciner son ideal politique dans une realite plus materielle, de facon a y puiser une nourriture concrete et substantielle. C'est une des raisons d'existence de la douzaine d'institutions specialisees gravitant dans la famille des Nations Unies et s'occupant de Sante, de Culture, d'Agriculture, de Finances, etc. Le nucleaire est l'une de ces techniques. Devenu soudainement un facteur primordial de puissance, Cristallisant a son benefice le prestige de la Science, c'etait un terrain de predilection pour le developpement du nouvel esprit, aussi bien sous la forme universelle de 1945, que sous les formes regionales qui ont vu le jour ensuite. Les travaux realises que nombreux, d

  16. 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)

  17. The Technical Training Programme for Nuclear Power Station Personnel; Programme de formation technique du personnel des centrales nucleaires; Programma tekhnicheskoj podgotovki personala yadernoj ehlektrostantsii; El programa de formacion tecnica del personal de una central nucleoelectrica

    Energy Technology Data Exchange (ETDEWEB)

    Howey, G. R. [Hydro-Electric Power Commission of Ontario, Toronto, Ontario (Canada)

    1963-10-15

    .), responsible for maintenance of all mechanical equipment; and (5) Service maintainers: responsible for a wide variety of less skilled tasks requiring lower qualifications. In addition to these general categories a few specialists are required, such as chemists and radiation protection officers. Organization of the NPD staff and training for future nuclear-power needs will be discussed. (author) [French] La centrale nucleaire de demonstration canadienne (NPD), creee par un organisme federal, l'Atomic Energy of Canada Limited, est exploitee par une compagnie provinciale de distribution d'electricite, la Hydro-Electric Power Commission of Ontario, qui pourvoit aussi aux besoins en personnel. Le recrutement et la formation du personnel de la centrale ont ete difficiles du fait que, recemment encore, la plupart des besoins en electricite de l'Ontario pouvaient etre satisfaits par les abondantes ressources hydro-electriques de cette province. La multiplication des centrales thermiques, depuis 1950, a cree une enorme demande de personnel. Pour faire face a cette situation, on a organise la formation de personnel pour les centrales nucleaires de la maniere suivante: a) un groupe initial d'ingenieurs a ete selectionne parmi des specialistes ayant une vaste experience des travaux dans le domaine nucleaire de l 'exploitation des centrales thermiques et de la production d'electricite; b) on a selectionne un autre groupe d'operateurs et d'agents des services d'entretien hautement qualifies; c) ces groupes ont recu une formation systematique comprenant l'exploitation de centrales nucleaires et de centrales thermiques a charbon, un enseignement theorique et pratique et des instructions donnees par les specialistes qui ont concu les plans de NPD ; d) un centre de formation nucleaire a ete cree et charge de la selection et de la formation du personnel supplementaire ainsi que de l 'organisation des examens officiels; il doit s'assurer, d'une maniere generale, de la competence du personnel

  18. Nuclear reactor (1960); Reacteurs nucleaires (1960)

    Energy Technology Data Exchange (ETDEWEB)

    Maillard, M L [Commissariat a l' Energie Atomique, Saclay (France).Centre d' Etudes Nucleaires; Leo, M B [Electricite de France (EDF), 75 - Paris (France)

    1960-07-01

    The first French plutonium-making reactors G1, G2 and G3 built at Marcoule research center are linked to a power plant. The G1 electrical output does not offset the energy needed for operating this reactor. On the contrary, reactors G2 and G3 will each generate a net power of 25 to 30 MW, which will go into the EDF grid. This power is relatively small, but the information obtained from operation is great and will be helpful for starting up the power reactor EDF1, EDF2 and EDF3. The paper describes how, previous to any starting-up operation, the tests performed, especially those concerned with the power plant and the pressure vessel, have helped to bring the commissioning date closer. (author) [French] Les premiers reacteurs industriels plutonigenes francais G1 - G2 - G3 du Centre de Marcoule comportent une installation de recuperation d'energie. La production d'electricite de G1 ne compense pas l'energie depensee par ailleurs pour le fonctionnement de l'ensemble, par contre, G2 et G3 doivent fournir chacun une puissance de 25 a 30 MW au reseau national d'Electricite de France. Cette puissance est modeste, mais l'experience acquise grace a ces reacteurs est tres grande et c'est grace a elle qu'il nous sera possible de mettre en exploitation les reacteurs energetiques EDF1 - EDF2 - EDF3. Le memoire decrit comment, avant tout demarrage du reacteur, les essais effectues, en particulier ceux concernant l'installation de recuperation d'energie et le caisson, ont permis d'abreger la phase de montee en puissance. (auteur)

  19. Thermoluminescent Dosimeter as the Gamma Component of a Nuclear Accident Dosimeter; Utilisation du Dosimetre Thermoluminescent Comme Element Detecteur Gamma d'un Dosimetre pour les cas d'Accident Nucleaire; 0422 0415 0420 041c 0414 ; Los Detectores de Termoluminiscencia Como Elemento Gammametrico de un Dosimetro para Casos de Accidente Nuclear

    Energy Technology Data Exchange (ETDEWEB)

    Handloser, J. S. [Edgerton, Germeshausen and Grier, Inc., Santa Barbara, CA (United States)

    1965-06-15

    dans les dosimetres a utiliser en cas d'accident. Il a essaye diverses sortes de dosimetres en verre, de dosimetres a films, de dosimetres chimiques et de dosimetres a polymerisation, mais le dosimetre thermoluminescent est celui qui presente le plus d'avantages. En raison de sa grande etendue de mesure, le dosimetre thermoluminescent peut etre utilise a la fois comme appareil de controle radiologique quotidien et comme dosimetre en cas d'accident. Ce systeme rend inutile remploi d'instruments speciaux pour la dosimetrie des accidents et permet d'utiliser a cette fin les instruments bien calibres d'usage quotidien. Habituellement, l'etendue de mesure d'un dosimetre thermoluminescent est de 5 mr a 100 000 r, avec une reproductibilite de {+-} 10%. L'auteur a concu et fabrique un modele unique de dosimetre a fluorure de calcium avec dispositif de lecture pouvant mesurer de 5 mr a 5000 r. La lecture du dosimetre est realisee par chauffage du phosphore et mesure de la lumiere emise. On dispose d'instruments de lecture a six echelles de graduation et des systemes entierement automatises sont prevus. La lecture a l'aide de chacun de ces appareils ne prend pas plus de 20 s par dosimetre. Un autre avantage du dosimetre thermoluminescent est sa faible reponse aux neutrons. La reponse aux neutrons varie selon le type du support et le type de phosphore. Un modele de dosimetre au fluorure de calcium a une reponse aux neutrons de 0.27 x 10{sup -9} rad/n/cm{sup 2}. L'auteur examine deux formes physiques de dosimetres thermoluminescents. Le premier est un dosimetre a chauffage interne place sous vide dans une capsule de verre; il a approximativement les dimensions suivantes: diametre 1 cm, longueur 6 cm. Le second modele est constitue par un tube de verre de faible section dans lequel le phosphore est scelle. Ce dosimetre a un diametre de 0,8 mm et une longueur de 6 mm. L'auteur a concu des ecrans de correction de la reponse a l 'energie pour ces deux types de dosimetres. (author

  20. Les Africaines Et Les Tic

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

    Enquête sur les technologies, la question de genre et autonomisation ...... Polachek, S. (1981) «Occupational self-selection: a human capital approach to sex ...... in the Computer Science major », Communications of the ACM, 44(5) : 108–14.

  1. Experimental study of flux depressions and anti-reactivities created by irradiation loops; Etude experimentale des depressions de flux et antireactivites creees par les dispositifs d'irradiation

    Energy Technology Data Exchange (ETDEWEB)

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

    1967-07-01

    Methods for fast computing of thermal flux depressions and reactivities created by irradiation-loops in natural water reactors are studied in this report. The classical methods of approximation which have been used are: diffusion theory or absorption-probability calculations for the flux-depression and perturbation theory for the anti-reactivities. Pertinent formulae are compiled together with graphs from theoretical calculations. These formulae and graphs have been checked from numerous experiments which show that the approximations used here are quite close to the actual physical situation, even when the theories are based from assumptions which cannot be verified here. (author) [French] Ce rapport propose aux experimentateurs des piles a eau legere des methodes de determination rapide des depressions de flux thermique et antireactivites creees par les dispositifs d'irradiation. Les methodes classiques d'approximation sont utilisees, a savoir: theorie de diffusion ou calcul de probabilites d'absorption pour les depressions de flux, theorie des perturbations pour les antireactivites. Un formulaire pratique, accompagne d'abaques est deduit des calculs theoriques et verifie par de nombreuses experiences qui montrent que les evaluations faites sont tres proches de la realite, meme dans le cas ou les hypotheses relatives aux theories utilisees ne sont pas respectees. (auteur)

  2. Nuclear raw materials; Matieres premieres nucleaires

    Energy Technology Data Exchange (ETDEWEB)

    Cameron, J. [Division of Nuclear Power and Reactors, International Atomic Energy Agency, Vienna (Austria)

    1970-01-15

    It is clear that in the next decades there will be a substantial and increasing demand for uranium to fuel nuclear power stations. In a developing country, the discovery and development of uranium resources can be of importance either for the development of national nuclear power or for the commercial export of uranium. As the time taken between the start of a uranium exploration program and the uranium production stage.may be of the order of 6 - 10 years, it is now opportune to start new exploration so that advantage of the increased demand in the mid-1970s may be achieved. Thorium will also be of interest, but in the more distant future when the thorium cycle for advanced converters and breeder reactors is fully developed [French] Il est certain qu' au cours des prochaines décennies la demande d'uranium pour les centrales nucléaires sera importante et ne cessera de croître. Dans un pays en voie de développement, la découverte et la mise en valeur de ressources d'uranium peut avoir une grande importance, soit en vue de produire de l'énergie nucléoélectrique, soit en vue d'exporter l'uranium. Etant donné que les délais entre le démarrage d'un programme de prospection de l'uranium et le début de la production peuvent être de l'ordre de six ans, il est actuellement opportun de commencer les opérations d'exploration pour pouvoir profiter de la demande accrue qui s' affirmera vers le milieu de la prochaine décennie. Le thorium présentera aussi un certain intérêt, mais à plus long terme. Il faut pour cela que le cycle du thorium pour convertisseurs avancés et surgénérateurs ait été pleinement développé. (author)

  3. Use of particles other than neutrons in activation analysis; Emploi de particules autres que les neutrons en analyse par actuation

    Energy Technology Data Exchange (ETDEWEB)

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

    1964-07-15

    Nuclear reactions obtained by irradiation in {gamma} Bremsstrahlung, {alpha} particles and protons are particularly suitable for dosing very small traces of light elements. We consider the possibilities presented by activation in {gamma} radiation of 28 MeV maximum energy, mainly for the measurement of C, F, N, O, P and S. Non-destructive methods of analysis for beryllium are described. Under certain conditions they may also be used for other elements such as B, Ca, Li and Na. We give also the results of our first experiments carried out in an attempt to find a method for dosing carbon and oxygen by irradiation in {alpha} particles and protons. For each type of activation the possible types of interference with other nuclear refections are considered. (author) [French] Des reactions nucleaires obtenues par irradiation dans des rayons {gamma} de freinage, des particules {alpha} et des protons, sont particulierement indiquees pour les dosages de traces ultimes de certains elements legers. Nous etudions les possibilites offertes par les activations en rayons {alpha} d'energie maximum 28 MeV, principalement pour les dosages de C, F, N, O, P et S. Des methodes d'analyse non destructives appliquees au beryllium sont decrites. Sous certaines conditions, elles peuvent egalement etre utilisees pour d'autres materiaux comme B, Ca, Li et Na. Nous donnons d'autre part les resultats de nos premieres experiences effectuees pour la mise au point des methodes de dosage du carbone et de l'oxygene par irradiation dans les particules {alpha} et les protons. Pour chaque type d'activation, les possibilites d'interferences avec d'autres reactions nucleaires sont examinees. (auteur)

  4. Analysis of crack initiation in the vicinity of an interface in brittle materials. Applications to ceramic matrix composites and nuclear fuels; Analyse de la fissuration au voisinage d'une interface dans les materiaux fragiles. Applications aux composites a matrice ceramique et aux combustibles nucleaires

    Energy Technology Data Exchange (ETDEWEB)

    Poitou, B

    2007-11-15

    In this study, criterions are proposed to describe crack initiation in the vicinity of an interface in brittle bi-materials. The purpose is to provide a guide for the elaboration of ceramic multi-layer structures being able to develop damage tolerance by promoting crack deflection along interfaces. Several cracking mechanisms are analyzed, like the competition between the deflection of a primary crack along the interface or its penetration in the second layer. This work is first completed in a general case and is then used to describe the crack deviation at the interface in ceramic matrix composites and nuclear fuels. In this last part, experimental tests are carried out to determine the material fracture properties needed to the deflection criteria. An optimization of the fuel coating can be proposed in order to increase its toughness. (author)

  5. Report by the AERES on the unit: Unit of researches on neutron transport and radioactivity confinement in nuclear installations under the supervision of the establishments and bodies: IRSN; Rapport de l'AERES sur l'unite: Unite de recherches en neutronique et confinement de la radioactivite dans les installations nucleaires sous tutelle des etablissements et organismes: IRSN

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2010-07-15

    This report is a kind of audit report on a research laboratory whose activity is organized in three departments: neutron transport and criticality (themes: numerical methods, maths and statistics related to the simulation of neutral particle propagation, nuclear data, uncertainty propagation and bias estimation, code qualification and associated experimental programs, neutron transport in reactors and fuel cycle, criticality accidents), radionuclide transfer in radioactive waste disposals (site identification strategy, hydro-mechanical phenomena affecting storage performance, physical-chemical evolution factors, storage modelling), and metrology and confinement of radioactive gases and aerosols. The authors discuss an assessment of the unit activities in terms of strengths and opportunities, aspects to be improved and recommendations, productions and publications. A more detailed assessment is presented for each department in terms of scientific quality, influence and attractiveness (awards, recruitment capacity, capacity to obtain financing and to tender, participation to international programs), strategy and governance, and project

  6. Balance between automation and human actions in nuclear power plant operation. Results of international cooperation; Equilibre entre automatisation et action humaine dans la conduite des centrale nucleaires, resultats de la cooperation internationale

    Energy Technology Data Exchange (ETDEWEB)

    Sun, B [CEA Centre d' Etudes Nucleaires de Fontenay-aux-Roses, 92 (France). Dept. d' Analyse de Surete; Bastl, W [Gesellschaft fuer Reaktorsicherheit m.b.H. (GRS), Garching (Germany); Olmstead, R [Atomic Energy of Canada Ltd, Mississauga (Canada); Oudiz, A [Electric Power Research Inst., Palo Alto, CA (United States); Jenkinson, J [Nuclear Electric PLC, Gloucester (United Kingdom); Kossilov, A [International Atomic Energy Agency, Vienna (Austria)

    1990-07-01

    Automation has long been an established feature of power plants. In some applications, the use of automation has been the significant factor which has enabled plant technology to progress to its current state. Societal demands for increased levels of safety have led to greater use of redundancy and diversity and this, in turn, has increased levels of automation. However, possibly the greatest contributory factor in increased automation has resulted from improvements in information technology. Much recent attention has been focused on the concept of inherently safe reactors, which may simplify safety system requirements and information and control system complexity. The allocation of tasks between man and machine may be one of the most critical activity in the design of new nuclear plants and major retro-fits and it therefore warrants a design approach which is commensurate in quality with the high levels of safety and production performance sought from nuclear plants. Facing this climate, in 1989 the International Atomic Energy Agency (IAEA) formed an advisory group from member countries with extensive experience in nuclear power plant automation. The task of this group was to advise on the appropriate balance between manual and automatic actions in plant operation. (author) [French] L'automatisation a longtemps ete une caracteristique bien etablie des centrales nucleaires. Dans certaines applications, l'utilisation de l'automatisation a ete le facteur decisif qui a permis a la technologie des centrales de progresser jusqu'a son etat actuel. Les exigences de l'opinion publique en matiere de securite renforcee ont conduit a l'utilisation d'une plus grande redondance et a une plus grande diversification et ceci, en retour, a encore accru le niveau d'automatisation. Toutefois, il est possible que le facteur preponderant de cet accroissement de l'automatisation soit constitue par les progres effectues dans la technologie de l'information. Plus recemment, l'attention s

  7. The atomic energy course of the 'Institut National des Sciences et Techniques nucleaires' at the centre d'Etudes Nucleaires at Saclay; L'enseignement de genie atomique de l'Institut national des Sciences et Techniques nucleaires au Centre d'Etudes nucleaires de Saclay

    Energy Technology Data Exchange (ETDEWEB)

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

    1958-07-01

    foreign students. 8- Annexe: list of courses, practical work, pile projects drawn up by the 1957 students. (author)Fren. [French] 1- Les raisons de sa creation. L'electricite de France et l'industrie interessee par le developpement de l'Energie atomique ont demande au Commissariat a l'Energie atomique de former des ingenieurs capables d'etudier des projets de piles et de diriger leur construction. 2- Recrutement et Droits d'inscription. Les demandes d'inscription ont toujours depasse les possibilites. Cette annee, les cours sont suivis par 74 eleves permanents, dont 20 etrangers, et une centaine d'auditeurs libres. Tous les elevont deja ingenieurs ou nantis de grades universitaires eleves. Droit d'inscription: 250 000 F pour les eleves, 125 000 F pour les auditeurs. 3- Organisation de l'Enseignement. II comprend deux options: physique et chimie et dans chaque option: une centaine de conferences, une trentaine de travaux pratiques, des stages dans les services, l'etude d'un projet de reacteur par un groupe de 4 ou 5 eleves. L'ensemble occupe l'annee universitaire du 1 novembre au 14 juillet. 4- Sanction. Un examen final combinant les notes de deux epreuves theoriques, des travaux pratiques, du stage, et du projet conduit a un diplome d'ingenieur en genie atomique. Il n'est pas cree en realite de nouveaux ingenieurs; une mention nouvelle est seulement ajoutee a un diplome deja acquis. Les resultats ont toujours ete excellents. Le pourcentage des echecs est tres faible. 5- Placement des Diplomes. Ils reviennent tous dans leurs industries d'origine qui ont paye leurs salaires et les droits d'inscription en se privant de leurs services pendant les neuf mois de duree des cours. 6- Creations analogues. Un cours analogue a ete cree au Centre d'Etudes Nucleaires de Grenoble. Tandis que celui de SACLAY s'adresse plus specialement aux ingenieurs deja en fonctions, celui de Grenoble est, en principe, destine aux jeunes ingenieurs sortant des ecoles. 7- Conclusion. L

  8. Padronização e avaliação histológica de um modelo experimental de lesão medular

    Directory of Open Access Journals (Sweden)

    José Ademar Villanova Junior

    2014-06-01

    Full Text Available A lesão medular é incapacitante, irreversível e de custo econômico e social elevado. Neste estudo, objetivou-se padronizar um modelo de lesão medular, que produza paraplegia, com o uso de cateter e avaliar histologicamente a efetividade da lesão para estudos com terapia celular. Foram realizadas as lesões medulares em ratos Wistar, utilizando-se o cateter Fogarty n.3 e compressão na região toracolombar (T8-T9 durante 5 minutos. Foram estudados três grupos: grupo A, animais controle sem lesão medular; grupo B, animais submetidos à lesão, utilizando-se 50µL de compressão; grupo C, animais submetidos à lesão, utilizando-se 80µL de compressão. Foi realizada avaliação motora pela aplicação da escala BBB, antes da compressão, após recuperação anestésica, 24 e 72 horas depois da compressão e sete dias após a compressão. Após o sétimo dia da lesão, os animais foram submetidos à eutanásia, foi feita a retirada da medula espinhal, fígado e rins e realizada a análise histológica com a coloração hematoxilina-eosina. A mortalidade variou entre os grupos, com 0% no grupo A, 38,5% no B e 48% no C. Nesses dois últimos grupos, a causa da morte foi edema pulmonar neurogênico, confirmado clínica e histologicamente. As medulas espinhais histologicamente apresentaram diferentes graus de edema, congestão vascular e hemorragia, enquanto que os fígados e os rins apresentaram diferentes graus de congestão vascular e necrose. Em relação à recuperação dos movimentos, no grupo A, verificou-se 100% de escore 21; no B, 25% de escore 21; 37,5% de escore 11; e 37,5% de escore 0; enquanto, no grupo C, verificou-se 100% de escore 0. Conclui-se que o procedimento realizado utilizando-se 80µL de solução salina para preencher o balão do cateter foi mais eficiente, apesar de maior mortalidade, pois apresentou maior porcentagem de animais com lesão completa (paraplegia.

  9. Study of transfers and their interactions with self-healing in the cracks to increase the service life of infrastructures (bridges, nuclear centrals); Etude des transferts et de leurs interactions avec la cicatrisation dans les fissures pour prolonger la duree de service des infrastructures (ponts, centrales nucleaires)

    Energy Technology Data Exchange (ETDEWEB)

    Ismail, M

    2006-04-15

    Concrete structures are frequently cracked by the action of different types of physicochemical mechanisms (external loads, restrained shrinkage, internal expansion). Cracks could impair the durability of concrete structures by creating preferential paths for the penetration of various types of potentially aggressive agents (liquids, gases, and ions). The aim of this thesis is to study transport properties in mechanically induced cracks. The first objective of the study is to better understand the potential effect of critical crack opening and self-healing. Cracks were generated in an inert material (brick) and in old mortar samples of 28 days and 2 years of age. A mechanical expansive core was used to generate cracks of constant width across the thickness of the sample. For the brick material, results show that a mechanical interaction between the fracture surfaces (critical crack opening) can affect the chloride-diffusion process along a crack path. A critical crack opening was also found for mortar samples. The age at which cracks were generated is also an important parameter. Self-healing was found to be more important in young mortars (28 days). The second objective of this thesis is the prediction of airflow in cracked cementitious material samples. A model proposed by Rizkalla et al. was evaluated through the experimental measurement of the flow coefficient n and the friction coefficient k. A simplified model was proposed to predict airflow through a crack for laminar type flow. The third research objective is to study the effect of self-healing on airflow through cracked mortar samples stored in a 100% relative humidity environment. Results show that self-healing mainly occurs during the first two months of storage. SEM analysis of fracture surfaces shows the formation of self-healing products such as calcite, C-S-H, and ettringite. (author)

  10. Study of the retention of radionuclides by ion-exchange resins contained in the circuits of a Pressurized Water Reactor; Etude de la retention des radionucleides dans les resines echangeuses d'ions des circuits d'une centrale nucleaire a eau sous pression

    Energy Technology Data Exchange (ETDEWEB)

    Gressier, F.

    2008-11-15

    Physico-chemical quality of fluids in nuclear power plant circuits must be maintained in order to limit contamination and dose rate especially when the shutdown takes place. Nevertheless, an optimum between diminishing liquid waste and limiting solid waste production has to be reached, but at affordable costs. Ion-exchange resins of purification circuits are used to fulfill this goal. In this work, different resin types have been characterized (exchange capacity, water and electrolyte sorption) and their selectivity towards Co{sup 2+}, Ni{sup 2+}, Cs{sup +} and Li{sup +} cations have been studied. We have shown that the two cation-exchange resins selectivity varies according to the nature and concentrations of their counter-ions. Moreover, flow rate (and thus hydro-kinetics) impact on species retention in a column has been characterized: the more the flow rate, the more the ionic leakage (output concentration divided by input concentration) is fast and the more the output concentration front is spread. A literature revue has enabled to put in light advantages and drawbacks of the models of interest to simulate operations of ion-exchange resins. Thus, the pure end-members mixing model associated to a non-ideality description of the resin phase based on the regular solutions model has been retained for modelling ion-exchange equilibrium. Ion-exchange kinetics has been described by mass transfer coefficients. Using the experimental results to determine model parameters, these last ones have been implemented in a speciation code CHESS, coupled with a hydrodynamic code in HYTEC. On the one hand, equilibrium experiments of ion retention have been simulated and, on the other hand, column retention tests have been modelled. Finally, selectivity variations and hydro-kinetics impacts have been simulated on some test cases so as to demonstrate the importance of taking these into account when simulating ion-exchange resins operations. (author)

  11. Nuclear fragmentation for Xe+Au and Xe+Ag systems at an energy of 44 A.MeV, formation and decay of hot nuclei; Etude de la fragmentation nucleaire pour les systemes XE+AU et XE+AG a 44 A.MeV, production et decroissance de noyaux chauds

    Energy Technology Data Exchange (ETDEWEB)

    Meslin, C.

    1995-01-01

    A study of the formation and the decay of hot nuclear fragments produced in the reactions Xe+Au and Xe+Ag at an energy of 44 A.MeV is presented in this thesis. The 4{pi} experimental setup consisted of four multidetectors -two for the detection of the fragments (Z>7; DELF and XYZT) and two for the detection of the charged particles (Z<6; MUR and TONNEAU) and allowed an analysis using ``complete events`` (80 % of the total charge and the total parallel linear momentum of the entrance channel) to be carried out. The reaction mechanism is binary with as observed at low energy an almost complete relaxation of the incident energy. The collision results in two hot fragments at the beginning of the exit channel which decay by evaporation and/or fragmentation. In addition of these two body events, we have identified a new dynamic mechanism where we detect a small fragment, called the neck, coming form the overlap of the nuclei during the interaction, in coincidence with a projectile-like fragment and a target-like fragment. For the most dissipative collisions, the deep inelastic collision have allowed an estimation of the lifetime of the hot nuclear fragments to be made. This is possible using proximity effects and fragment-fragment space-time correlations of the decay of one or two primary partners from the deep inelastic collisions. This method is seen to reach its limits in the case of the reactions studied here. (authors). 61 refs.

  12. Defect assessment in nuclear components: R and D related to industrial problems - synthesis of the research, training and teaching activities; Analyse de nocivite de defauts dans les structures nucleaires: R et D associee aux problemes industriels - synthese des activites de recherche, d'encadrement et d'enseignement

    Energy Technology Data Exchange (ETDEWEB)

    Marie, St

    2007-06-15

    Nuclear industry pays a particular attention to structures integrity problems: well-aware of the possible catastrophic consequence of a major accident, everything is carried out to minimise the risk of such a situation. From the design, and during all the operating life of the plant, a high level of safety is required and checks by the safety authorities, on the basis of reports made by the operator. These two entities ask for R and D activities to support the improvement of the knowledge of the phenomena already identified (as in the case of the vessel of the PWR) or to bring some element of understanding to situation not considered yet, up to the first incident (as in 1998 with the fatigue problems in the thermal mixing zone, at the origin of the Civaux arrest). Among the CEA teams concerned with these problems, the Laboratory of the Structures Integrity and of Normalisation aims to study the integrity problems in metallic nuclear structures leaning on exceptional experimental means: the RESEDA platform allows the realisation of large-scaled tests on analytical tests (representative of analysed phenomena) to reproduce the industrial situation, linked to various and accurate equipment for the measures and the analyses. Three industrial thematics represent to main part of my research activities at CEA in the fracture mechanics field: - the industrial case of the PWR vessel is related to brittle fracture of the ferritic steels, - the piping components, related to ductile tearing and fracture in the brittle-to-ductile domain, - the high temperature fracture mechanics for the components submitted to very complex loadings. (author)

  13. Study of the influence of the shell correction energy on the nuclear reactions leading to the region of the superheavy nuclei; Etude de l'influence de l'energie de correction de couches sur les reactions nucleaires menant a la region des noyaux superlourds

    Energy Technology Data Exchange (ETDEWEB)

    Marchix, A

    2007-11-15

    The aim of this work is to study the influence of shell correction energy on the deexcitation of superheavy nuclei. For that purpose, a new statistical code, called Kewpie2, which is based on an original algorithm allowing to have access to very weak probabilities, was developed. The results obtained with Kewpie2 have been compared to the experimental data on residue cross sections obtained by cold fusion (Z=108 to Z=113) and by hot fusion (Z=112, Z=114 and Z=116), as well as data on fission times (Z=114, Z=120 and Z=126). Constraints on the microscopic structure of the studied nuclei have been obtained by means of the shell correction energy. By adjusting the intrinsic parameters of the models of fusion in order to reproduce the data on the fusion cross sections, this study shows the necessity of decreasing very strongly the shell correction energy predicted by the calculations of Moller and Nix, during the study of the residues cross sections as well for the nuclei produced by cold fusion as by hot fusion. On the other hand, during the confrontation of the results of Kewpie2 to the data on mean fission times, it is rather advisable to increase it. A shift of the proton shell closure predicted for Z=114 by the calculations of Moller and Nix towards larger Z would allow to explain these opposite conclusions. In this thesis, we also have shown the significant influence of the inclusion of isomeric states on fission times for the superheavy nuclei. (author)

  14. Defect assessment in nuclear components: R and D related to industrial problems - synthesis of the research, training and teaching activities; Analyse de nocivite de defauts dans les structures nucleaires: R et D associee aux problemes industriels - synthese des activites de recherche, d'encadrement et d'enseignement

    Energy Technology Data Exchange (ETDEWEB)

    Marie, St

    2007-06-15

    Nuclear industry pays a particular attention to structures integrity problems: well-aware of the possible catastrophic consequence of a major accident, everything is carried out to minimise the risk of such a situation. From the design, and during all the operating life of the plant, a high level of safety is required and checks by the safety authorities, on the basis of reports made by the operator. These two entities ask for R and D activities to support the improvement of the knowledge of the phenomena already identified (as in the case of the vessel of the PWR) or to bring some element of understanding to situation not considered yet, up to the first incident (as in 1998 with the fatigue problems in the thermal mixing zone, at the origin of the Civaux arrest). Among the CEA teams concerned with these problems, the Laboratory of the Structures Integrity and of Normalisation aims to study the integrity problems in metallic nuclear structures leaning on exceptional experimental means: the RESEDA platform allows the realisation of large-scaled tests on analytical tests (representative of analysed phenomena) to reproduce the industrial situation, linked to various and accurate equipment for the measures and the analyses. Three industrial thematics represent to main part of my research activities at CEA in the fracture mechanics field: - the industrial case of the PWR vessel is related to brittle fracture of the ferritic steels, - the piping components, related to ductile tearing and fracture in the brittle-to-ductile domain, - the high temperature fracture mechanics for the components submitted to very complex loadings. (author)

  15. Les choses…

    Directory of Open Access Journals (Sweden)

    Pierre Curie

    2012-05-01

    Full Text Available Dans la culture tant des Monuments historiques que de l’Université française, le monumental a longtemps prévalu sur l’objet, peinture, sculpture ou objet d’art qui, lui, dans l’inconscient collectif, relevait tout naturellement du musée. Dans la pensée et dans les goûts d’André Chastel, les catégories n’étaient pas aussi manichéennes et à l’Inventaire, malgré une certaine prééminence de l’architecture, l’objet - au sens large - tint, dès le début de l’aventure, une place non négligeable. Le premier des Vocabulaires parus, en 1969, fut consacré à la tapisserie, suivi, en une vingtaine d’années, par la sculpture, les objets et le mobilier civil domestique, le vitrail…In the culture of France’s historic monuments, as in French universities, the monumental has long been considered as more important than sculptures or works of art, generally seen as more to do with museums. In the writings and tastes of André Chastel, however, the categories were not so clear-cut and, at the French Inventory, although architecture has enjoyed a certain pre-eminence, the object, in the broadest sense of the term, has been taken into consideration form the outset. Over 17,000 items now feature in the national database Palissy, on moveable objects. The first scientific vocabulary, published by the Inventory services in 1969, was devoted to tapestry and, over the last twenty years, other vocabularies have dealt with sculpture, domestic civil furniture and stained glass.

  16. Numerical simulation and analysis of axial instabilities occurrence and development in turbomachines. Application to a break transient in a helium nuclear reactor; Simulation numerique et analyse du declenchement et du developpement des instabilites axiales dans les turbomachines: application a un transitoire de breche dans un reacteur nucleaire a helium

    Energy Technology Data Exchange (ETDEWEB)

    Tauveron, N

    2006-02-15

    The subject of the present work was to develop models able to simulate axial instabilities occurrence and development in multistage turbomachines. The construction of a 1D unsteady axisymmetric model of internal flow in a turbomachine (at the scale of the row) has followed different steps: generation of steady correlations, adapted to different regimes (off-design conditions, low mass flowrate, negative mass flow rate); building of a model able to describe transient behaviour; use of implicit time schemes adapted to long transients; validation of the model in comparison of experimental investigations, measurements and numerical results from the bibliography. This model is integrated in a numerical tool, which has the capacity to describe the gas dynamics in a complete circuit containing different elements (ducts, valves, plenums). Thus, the complete model can represent the coupling between local and global phenomena, which is a very important mechanism in axial instability occurrence and development. An elementary theory has also been developed, based on a generalisation of Greitzer's model. These models, which were validated on various configurations, have provided complementary elements for the validation of the complete model. They have also allowed a more comprehensive description of physical phenomena at stake in instability occurrence and development by quantifying various effects (inertia, compressibility, performance levels) and underlying the main phenomena (in particular the collapse and recovery kinetics of the plenum), which were the only retained in the final elementary theory. The models were first applied to academic configurations (compression system), and then to an innovative industrial project: a helium cooled fast nuclear reactor with a Brayton cycle. The use of the models have brought comprehensive elements to surge occurrence due to a break event. It has been shown that surge occurrence is highly dependent of break location and that surge

  17. Numerical simulation and analysis of axial instabilities occurrence and development in turbomachines. Application to a break transient in a helium nuclear reactor; Simulation numerique et analyse du declenchement et du developpement des instabilites axiales dans les turbomachines: application a un transitoire de breche dans un reacteur nucleaire a helium

    Energy Technology Data Exchange (ETDEWEB)

    Tauveron, N

    2006-02-15

    The subject of the present work was to develop models able to simulate axial instabilities occurrence and development in multistage turbomachines. The construction of a 1D unsteady axisymmetric model of internal flow in a turbomachine (at the scale of the row) has followed different steps: generation of steady correlations, adapted to different regimes (off-design conditions, low mass flowrate, negative mass flow rate); building of a model able to describe transient behaviour; use of implicit time schemes adapted to long transients; validation of the model in comparison of experimental investigations, measurements and numerical results from the bibliography. This model is integrated in a numerical tool, which has the capacity to describe the gas dynamics in a complete circuit containing different elements (ducts, valves, plenums). Thus, the complete model can represent the coupling between local and global phenomena, which is a very important mechanism in axial instability occurrence and development. An elementary theory has also been developed, based on a generalisation of Greitzer's model. These models, which were validated on various configurations, have provided complementary elements for the validation of the complete model. They have also allowed a more comprehensive description of physical phenomena at stake in instability occurrence and development by quantifying various effects (inertia, compressibility, performance levels) and underlying the main phenomena (in particular the collapse and recovery kinetics of the plenum), which were the only retained in the final elementary theory. The models were first applied to academic configurations (compression system), and then to an innovative industrial project: a helium cooled fast nuclear reactor with a Brayton cycle. The use of the models have brought comprehensive elements to surge occurrence due to a break event. It has been shown that surge occurrence is highly dependent of break location and that surge

  18. Les incommensurables

    CERN Document Server

    Houdart, Sophie

    2015-01-01

    Le Large Hadron Collider, ou grand collisionneur de hadrons, est l'accélérateur de particules le plus grand et le plus puissant du monde. Prenant la forme d'un anneau de 26,659 kilomètres de circonférence, lové 100 mètres sous terre et officiellement domicilié à Meyrin, à la frontière de la France et de la Suisse, il est constitué d'aimants supraconducteurs et de structures accélératrices qui augmentent l'énergie des particules qui y circulent. Chaque jour, à l'intérieur de l'accélérateur, deux faisceaux de particules qui circulent en sens contraire à des énergies très élevées avant de rentrer en collision l'un avec l'autre. Les particules, lancées à 99,9999991 % de la vitesse de la lumière, effectuent 11245 fois le tour de l'accélérateur par seconde et entrent en collision quelque 600 millions de fois par seconde. Les Incommensurables est une minutieuse enquête de terrain sur cette "cathédrale" enfouie qui offre la possibilité de se connecter à l'immensité et aux mystères de...

  19. Optimal sizes and siting of nuclear fuel reprocessing plants; Tailles et localisations optimales des usines de retraitement des combustibles nucleaires

    Energy Technology Data Exchange (ETDEWEB)

    Thiriet, L; Deledicq, A [Commissariat a l' Energie Atomique, Siege (France). Centre d' Etudes Nucleaires

    1967-07-01

    traite le probleme des usines de traitement de l'uranium naturel irradie associees a des centrales nucleaires a uranium naturel-graphite CO{sub 2}. La localisation et la production annuelle des reacteurs, les sites possibles d'usines et les fonctions de cout (transport et retraitement) sont supposes connus. La methode consiste a traiter d'abord le probleme des usines de traitement comme un probleme de programmation dynamique, des tranches croissantes de programmes (production totale des reacteurs) etant explorees sequentiellement. Lorsque les quantites d'uranium naturel irradie a retraiter sont fixees, la minimisation du cout de transport est alors effectuee, elle aussi comme un probleme de programmation dynamique. On explore le voisinage de l'optimum du cout de traitement pour trouver le minimum de la somme d'un cout de traitement sous-optimal et du cout de transport optimal correspondant. Le probleme de retraitement etant representable sur un graphe sequentiel, l'algorithme utilise pour calculer les sous-optima est 'l'algorithme a reflexion' que nous avons elabore. La methode s'interprete comme un mecanisme general de determination de l'optimum lorsque, a un probleme dynamique sequentiel (par exemple un programme d'equipement), se superpose un probleme complementaire (par exemple de transport). Elle permet en outre d'evaluer les pertes resultant du choix, pour des raisons autres qu'economiques, d'une politique non optimale. (auteur)

  20. Special Nuclear Material Control by the Power Reactor Operator; Controle des Matieres Nucleaires Speciales par l'Exploitant d'une Centrale Nucleaire; Spetsial'nyj kontrol' nalichiya yadernykh materialov operatorom ehnergeticheskogo reaktora; Control de Materiales Nucleares Especiales por Parte de Quienes Operan el Reactor de Potencia

    Energy Technology Data Exchange (ETDEWEB)

    Cordin, R. A. [Yankee Atomic Electric Company, Boston, MA (United States)

    1966-02-15

    insurance programme. (author) [French] L'uranium, combustible relativement nouveau et extremement interessant pour la production d'electricite, doit faire l'objet d'un controle tres strict depuis le moment ou l'exploitant de la centrale en devient financierement responsable jusqu'a celui oti, sous forme de combustible partiellement epuise, la matiere est transferee dans une autre installation et oti l'on recupere ce qui reste de sa valeur initiale. La plupart des exploitants de centrales nucleaires dirigeaient des centrales alimentees par des combustibles fossiles avant l'avenement de l'energie nucleaire et ils ont etabli depuis longtemps un controle etendu et efficace de ces combustibles fossiles. L'exploitant d'une centrale nucleaire doit exercer un controle non moins efficace sur les matieres nucleaires speciales utilisees dans son installation. La technique de l'exploitation des centrales nucleaires n'est pas ancienne et, au cours de, son existence relativement breve, les ingenieurs et hommes de science des Etats-Unis ont constamment ameliore les plans des centrales et les methodes d'exploitation afin de reduire les couts et de permettre aux centrales nucleaires de concurrencer les centrales classiques. La gestion des matieres nucleaires doit etre aussi moderne et efficace que possible pour assurer que les progres technologiques grace auxquels les prix on pu etre reduits ne soient pas mis en echec par des insuffisances dans la manipulation du combustible nucleaire et la tenue de la comptabilite des stocks. Pour assurer la gestion des matieres nucleaires, il faut que l'exploitant de la centrale etablisse et tienne a jour une comptabilite complete et detaillee, sans etre necessairement complexe pour autant; en fait, la simplicite est extremement souhaitable. Bien que le combustible nucleaire soit nouveau et qu'il n'ait rien de commun avec les combustibles classiques, aucun secret ne doit s'y attacher. Le controle des matieres nucleaires dans le cadre de la gestion des

  1. Cooperation in the Event of Nuclear Accidents; Cooperation en Matiere d'Accidents Nucleaires

    Energy Technology Data Exchange (ETDEWEB)

    Bresson, G. [CEA, Centre d' etudes nucleaires, de Fontenay-aux-Roses (France)

    1969-10-15

    This paper is concerned only with the action to be taken in respect of an individual directly affected by an accident and not with the more general measures relating to the population as a whole. Keeping the same sequence of ideas, the paper deals with nuclear establishments and cites criteria for classifying them; hence only the relationship between the establishment and the hospital, and between the radiation protection experts and medical personnel, is discussed. The complex organization of emergency measures, reception of the victim of the accident, and the treatment possibly required should be based on standard practice and published material, both national and international, allowance being made for the characteristics of each sector. A ''flexible'' plan of co-ordination is given as an illustration. Action must be taken in such cases at the site of the accident, inside and outside the establishment, and above all at the hospital. All categories of persons are involved in the process, i.e. fellow-workers, management, specialized services, and medical personnel, each with their own part to play. The manpower and equipment brought into service therefore vary, and depend upon the internal and external relations maintained by the establishment. The measures envisaged should provide for the transport, reception and treatment of those involved in the accident. An existing organization of this kind is described as an illustration. Finally, no action can be of value without full knowledge of the facts and thorough training of the personnel. Some clearly defined ideas on the.subject are considered under this heading. (author) [French] Le memoire ne traite que de la conduite a tenir envers un accidente et non du probleme, plus general, des mesures relatives a une population. Dans le meme ordre d'idees, l'etude porte sur les etablissements nucleaires et leurs criteres de classement; il ne s'agit donc que des liaisons entre retablissement et l'hopital et entre les

  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. Shippingport Atomic Power Station Operating Experience, Developments and Future Plans; La centrale nucleaire de Shippingport, experience de son fonctionnement et plans pour l'avenir; Shippingportskaya atomnaya ehlektrostantsij, opyt ehkspluatatsii, usovershenstvovaniya i plany na budushchee; Central nucleoelectrica de Shippingport; experiencia adquirida con su explotacton y programa de desarrollo

    Energy Technology Data Exchange (ETDEWEB)

    Feinroth, H. [Division of Reactor Development, United States Atomic Energy Commission, Washington, DC (United States); Oldham, G. M. [Shippingport Atomic Power Station, Duquesne Light Company, Pittsburgh, PA (United States); Stiefel, J. T. [Bettis Atomic Power.Labora Tory, Westinghouse Electric Corporation, Pittsburgh, PA (United States)

    1963-10-15

    design rating of 150 MW(e) gross and a first seed life of 10.000 effective full power hours (EFPH), Core 2 will have five and a half times the design energy output and twice the power density of Core 1. The Core 2 design is described and associated major developments in reactor physics, metallurgy, heat transfer and fluid flow, and fuel element manufacture, are summarized. Plans for decontamination of the reactor plant and for performing modifications to the plant in connection with the installation of the higher rated Core 2 are described. (author) [French] Les auteurs font le bilan des cinq annees de fonctionnement et d'essai de la centrale nucleaire de Shippingport; ils examinent les progres techniques actuels et l'avenir du programme de Shippingport. Ce programme vise a mettre au point la technologie fondamentale des reacteurs a eau legere pour permettre une reduction du prix de revient de l'energie d'origine nucleaire. La centrale nucleaire de Shippingport fonctionne depuis plus de 5 ans et s'est integree facilement dans un reseau d'interconnexion comme centrale de base ou comme centrale d'appoint. Les divers elements de la centrale se sont reveles d'un fonctionnement sur. Il n'y a pas eu de probleme de contamination ni d'elimination des dechets. On peut acceder facilement aux elements du circuit primaire de refroidissement pour l'entretien et, ce faisant, on a constate que les cartouches de combustible etaient intactes. Chacune des trois operations de rechargement effectuees depuis le demarrage de la centrale a pris moins de temps que la precedente. Recemment, la troisieme charge de combustible enrichi a ete mise en place en 32 journees de travail, soit environ le quart du temps necessaire pour le premier rechargement. Les auteurs exposent les conditions auxquelles doit satisfaire la formation du personnel et donnent un apercu des instructions ecrites en matiere d'administration, d'exploitation, etc., qui sont autant de facteurs essentiels du succes du programme de

  4. Experimental contamination of margaritana margaritifera (L) (a Fresh water bivalve) by caesium 137; Contamination experimentale de margaritana margaritifera (L) (bivalve d'eau douce) par le cesium 137

    Energy Technology Data Exchange (ETDEWEB)

    Foulquier, L; Bovard, P; Grauby, A [Commissariat a l' Energie Atomique, Cadarache (France). Centre d' Etudes Nucleaires

    1966-07-01

    The hydro biological research carried out in the Radio-Ecology Section has led the authors to study some Margaritana sampling stations situated down-stream from the Monts d'Arree nuclear power station. They describe the preservation and contamination methods used for fixing the {sup 137}Cs concentration factors in the case of Margaritana Margaritifera (L). The results of experiments carried out over a period of one hundred days show that the specific activity of the various organs is stabilized after thirty to thirty-five days. The authors have noticed a relatively low adsorption on the shell through the intermediary of micro-organisms, and a strong and rapid absorption in the soft parts. The concentration factors have values, at equilibrium, of around: 9 for the shell, 300 for all the organs, and 38 for the whole animal. A comparison of these results with work published by other authors makes it possible to draw general conclusions concerning the mechanism of {sup 137}Cs fixation by lamellibranch, as well as their capacity of fixation. (author) [French] Les etudes hydrobiologiques effectuees au sein de la Section de Radio-Ecologie ont amene les auteurs a etudier des stations de prelevement de Margaritana en aval de la Centrale Nucleaire des Monts d'Arree. Ils decrivent les methodes de conservation et de contamination utilisees pour l'etablissement des facteurs de concentration du {sup 137}Cs par Margaritana margaritifera (L). Les resultats des experimentations menees pendant cent jours montrent que les activites specifiques de la coquille et des differents organes se stabilisent au bout de trente a trente-cinq jours. Les auteurs constatent une adsorption relativement faible sur la coquille par l'intermediaire des micro-organismes et une absorption forte et rapide dans les parties molles. Les facteurs de concentration se situent, a l'equilibre, autour de: 9 pour la coquille, 300 pour l'ensemble des organes et 38 si l'on considere l'animal total. Cette etude

  5. Elecnuc. Nuclear power plants worldwide; Elecnuc. Les centrales nucleaires dans le monde

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-07-01

    This small folder presents a digest of some useful information concerning the nuclear power plants worldwide and the situation of nuclear industry at the end of 1997: power production of nuclear origin, distribution of reactor types, number of installed units, evolution and prediction of reactor orders, connections to the grid and decommissioning, worldwide development of nuclear power, evolution of power production of nuclear origin, the installed power per reactor type, market shares and exports of the main nuclear engineering companies, power plants constructions and orders situation, evolution of reactors performances during the last 10 years, know-how and development of nuclear safety, the remarkable facts of 1997, the future of nuclear power and the energy policy trends. (J.S.)

  6. The radioactive wastes management; Le dossier: les dechets nucleaires et leur gestion

    Energy Technology Data Exchange (ETDEWEB)

    Rigny, P. [Actualite Chimique, 75 - Paris (France); Bonin, B. [CEA Saclay, Dir. de l' Energie Nucleaire, 91 - Gif sur Yvette (France); Gras, J.M. [Electricite de France (EDF-RD), Recherche et Developpement, 78 - Chatou (France)

    2010-11-15

    The different types of radioactive waste are presented in this paper in the frame of the official categories which take into account their dangerousness and the lifetimes of their radioactivity. It is indicated how the less dangerous of them are handled in France. The ways of protecting the environment from the more dangerous ones (high activity and long lifetimes) are object of studies. Scientific questions, in the field of chemistry and physical chemistry, related to the implementation of deep underground repository facilities with full respect of nuclear safety are presented. (authors)

  7. Nuclear wastes: status and perspectives; Les Dechets nucleaires: etat des lieux et perspectives

    Energy Technology Data Exchange (ETDEWEB)

    Barre, B.; Bazile, F.; Bonin, B.; Marvy, A.; Ouzounian, G.; Wizsenfeld, B.

    2011-07-01

    Radioactive wastes are considered by the large public as a problem which mortgages the future of nuclear industry. Today, the main principles of radioactive wastes management are defined: separation, conditioning, storage and disposal are the main elements of a strategy allowing to protect the man and the environment from the impacts of the inevitable ultimate wastes. In a period of debate concerning the future of these wastes, this book aims at supplying to the public the elements which will allow him to build his own opinion about this hot topic. (J.S.)

  8. The diverse applications of the nuclear power; Les diverses applications du nucleaire

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2004-07-01

    The three great categories of application in industry and environment of ionizing radiations are the use of ionizing radiation to transport energy in matter it is industrial irradiation, the use of radioactive sources of low activity to analyze and measure, it is the nucleonic instrumentation, the use of radioactive tracers to follow and study the matter transfer. Are explained the treatments to improve the plastic materials and the ionisation of food. (N.C.)

  9. Radioactive wastes: a world problem. Les dechets nucleaires: un probleme mondial

    Energy Technology Data Exchange (ETDEWEB)

    Schapira, J P [Centre National de la Recherche Scientifique (CNRS), 75 - Paris (FR)

    1991-02-01

    In all countries endowed with nuclear program, radioactive wastes disposal asks scientific and public acceptance problems. This paper describes several aspects: technical problem; ethic problem and responsibility towards future generations at very long-term; political problem. Different politics followed by concerned countries and recent controversy in France is also entered upon radioactive wastes underground site selection, in deep geological formations.

  10. The wastes of nuclear fission; Les dechets de la fission nucleaire

    Energy Technology Data Exchange (ETDEWEB)

    Doubre, H. [Paris-11 Univ., Centre de Spectrometrie Nucleaire et de Spectrometrie de Masse, IN2P3/CNRS, 91 - Orsay (France)

    2005-07-01

    In this paper the author presents the problems of the radioactive wastes generated by the nuclear fission. The first part devoted to the fission phenomenon explains the incident neutron energy and the target nuclei role. The second part devoted to the nuclear wastes sources presents the production of wastes upstream of the reactors, in the reactors and why these wastes are dangerous. The third part discusses the radioactive wastes management in France (classification, laws). The last part details the associated research programs: the radionuclides separation, the disposal, the underground storage, the transmutation and the thorium cycle. (A.L.B.)

  11. Elecnuc. Nuclear power plants in the world; Elecnuc. Les centrales nucleaires dans le monde

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-07-01

    This small booklet summarizes in tables all the numerical data relative to the nuclear power plants worldwide. These data come from the French CEA/DSE/SEE Elecnuc database. The following aspects are reviewed: 1999 highlights; main characteristics of the reactor types in operation, under construction or on order; map of the French nuclear power plants; worldwide status of nuclear power plants at the end of 1999; nuclear power plants in operation, under construction and on order; capacity of nuclear power plants in operation; net and gross capacity of nuclear power plants on the grid and in commercial operation; grid connection forecasts; world electric power market; electronuclear owners and share holders in EU, capacity and load factor; first power generation of nuclear origin per country, achieved or expected; performance indicator of PWR units in France; worldwide trend of the power generation indicator; 1999 gross load factor by operator; nuclear power plants in operation, under construction, on order, planned, cancelled, shutdown, and exported; planning of steam generators replacement; MOX fuel program for plutonium recycling. (J.S.)

  12. Elecnuc. Nuclear power plants in the world; Elecnuc. Les centrales nucleaires dans le monde

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2008-07-01

    This small booklet summarizes in tables all data relative to the nuclear power plants worldwide. These data come from the IAEA's PRIS and AREVA-CEA's GAIA databases. The following aspects are reviewed: 2007 highlights; Main characteristics of reactor types; Map of the French nuclear power plants on 2007/01/01; Worldwide status of nuclear power plants (12/31/2007); Units distributed by countries; Nuclear power plants connected to the Grid- by reactor type groups; Nuclear power plants under construction on 2007; Evolution of nuclear power plants capacities connected to the grid; First electric generations supplied by a nuclear unit in each country; Electrical generation from nuclear power plants by country at the end 2007; Performance indicator of French PWR units; Evolution of the generation indicators worldwide by type; Nuclear operator ranking according to their installed capacity; Units connected to the grid by countries at 12/31/2007; Status of licence renewal applications in USA; Nuclear power plants under construction at 12/31/2007; Shutdown reactors; Exported nuclear capacity in net MWe; Exported and national nuclear capacity connected to the grid; Exported nuclear power plants under construction; Exported and national nuclear capacity under construction; Nuclear power plants ordered at 12/31/2007; Long term shutdown units at 12/31/2007; COL (combined licences) applications in the USA; Recycling of Plutonium in reactors and experiences; Mox licence plants projects; Appendix - historical development; Meaning of the used acronyms; Glossary.

  13. Elecnuc. Nuclear power plants in the world; Elecnuc. Les centrales nucleaires dans le monde

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2003-07-01

    This 2003 version of Elecnuc contents information, data and charts on the nuclear power plants in the world and general information on the national perspectives concerning the electric power industry. The following topics are presented: 2002 highlights; characteristics of main reactor types and on order; map of the French nuclear power plants; the worldwide status of nuclear power plants on 2002/12/3; units distributed by countries; nuclear power plants connected to the Grid by reactor type groups; nuclear power plants under construction; capacity of the nuclear power plants on the grid; first electric generations supplied by a nuclear unit; electrical generation from nuclear plants by country at the end 2002; performance indicator of french PWR units; trends of the generation indicator worldwide from 1960 to 2002; 2002 cumulative Load Factor by owners; nuclear power plants connected to the grid by countries; status of license renewal applications in Usa; nuclear power plants under construction; Shutdown nuclear power plants; exported nuclear power plants by type; exported nuclear power plants by countries; nuclear power plants under construction or order; steam generator replacements; recycling of Plutonium in LWR; projects of MOX fuel use in reactors; electricity needs of Germany, Belgium, Spain, Finland, United Kingdom; electricity indicators of the five countries. (A.L.B.)

  14. Licence prolongations of US nuclear power plants; Les prolongations de licence des centrales nucleaires americaines

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2004-04-01

    Licences of US nuclear reactors were initially attributed for a 40 years duration. However, the vast majority of the reactors can benefit of a licence prolongation for a period of 20 years maximum. This article recalls first the procedure to follow for the licence prolongation demands (safety analysis, components aging, environmental impact statement), and then it makes a status of the accepted prolongations, of the demands under examination, and of the demands that should be presented in the next 5 years. (J.S.)

  15. Nuclear energy and its synergies with renewable energies; Le nucleaire dans ses synergies avec les renouvelables

    Energy Technology Data Exchange (ETDEWEB)

    Carre, F. [CEA Saclay, DEN, 91 - Gif-sur-Yvette (France); Mermilliod, N. [CEA Grenoble, Dir. de la Recherche Technologique, 38 (France); Devezeaux De Lavergne, J.G. [CEA Saclay, Dir. de l' Institut de tecchnico-economie des systemes energetiques I-tese, 91 - Gif-sur-Yvette (France); Durand, S. [CEA Grenoble, European Institute of Technology -KIC InnoEnergy, 38 (France)

    2011-05-15

    France has the ambition to become a world leader in both nuclear industry and in renewable energies. 3 types of synergies between nuclear power and renewable energies are highlighted. First, nuclear power can be used as a low-carbon energy to produce the equipment required to renewable energy production for instance photovoltaic cells. Secondly, to benefit from the complementary features of both energies: continuous/intermittency of the production, centralized/local production. The future development of smart grids will help to do that. Thirdly, to use nuclear energy to produce massively hydrogen from water and synthetic fuels from biomass. (A.C.)

  16. The American and Russian plans of nuclear disarmament; Les plans americain et sovietique de desarmement nucleaire

    Energy Technology Data Exchange (ETDEWEB)

    Gallois, P.

    2010-07-15

    This text was published in 1991, at the end of the Cold War. The author comments the intentions of the US and Russia leaders, Bush and Gorbachev, on nuclear disarmament and more specifically on limitations and reductions concerning the different nuclear weapons types and vectors (ballistic missiles, submarine launched missiles, Europe-based missiles, nuclear strategic warheads, nuclear weapon movements, short range missiles, cruise missiles). He also evokes the consequences for France of the American propositions

  17. Particles identification using nuclear emulsion in OPERA; Identification des particules par les emulsions nucleaires dans OPERA

    Energy Technology Data Exchange (ETDEWEB)

    Manai, K

    2007-10-15

    The Opera experiment will try to confirm the {nu}{sub {mu}} {yields} {nu}{sub {tau}} oscillations by the appearance of the {nu}{sub {tau}} in a pure {nu}{sub {mu}} beam. Indeed, a neutrino beam almost pure is produced at CERN (CNGS Beam) and sent to the Opera detector. The detector is composed of two muons spectrometers and a target formed by walls of bricks. Each brick is an alternation of lead plates and emulsions. This modular structure allows to reconstruct the kink topology of the {tau} lepton decay with a high spatial resolution. The great challenge of the Opera experiment is to detect the {nu}{sub {tau}} interactions with the less uncertainty. To reduce this uncertainty it is essential to identify with the greatest efficiency any background event not including a tau particle. My work permits to reduce background. My principal contribution concerns the selection development, the reconstruction and the muons identification at low energy. This work is based on the setting of variables related to the deposit energy and the multiple scattering. Previously, only deposit energy was used in the analyses of pion/muon separation. This study allows doubling the muon identification efficiency at low energy. This leads to increase the background events rejection in Opera and to decrease the contamination by 30%. I also studied the nuclear emulsions capacity to identify charged particles through the analysis of a test beam carried out by the Nagoya group. This test contains protons and pions with different energies. My work proves that the European scan system gives comparable results with those obtained by the Japanese scan system. (author)

  18. Risk analysis of industrial plants operation; Integration des evenements accidentels dans les bilans sur les nuisances industrielles

    Energy Technology Data Exchange (ETDEWEB)

    Hubert, Philippe

    1989-12-01

    This study examines the possibilities of systematic technology risk analysis in view of territorial management (city, urban community, region), including chronic and accidental risks. The objective was to relate this evaluation with those done for permanent water and air pollution. Risk management for pollution are done for a long time. A number of studies were done in urban communities and regions both for air and water pollution. The second objective is related to management of industrial risks: nuclear, petrochemical, transport of hazardous material, pipelines, etc. At the beginning, three possibilities of effects are taken into account: human health, economic aspect and water, and possibilities of evaluation are identified. Elements of risk identification are presented for quantification of results. [French] Cette etude examine les possibilites d'une analyse systematique du risque accidentel technologique dans une optique d'evaluation et de gestion territoriale (ville, communaute urbaine, region), qui integre: tous les types de risque chroniques et accidentels. Un des objectifs est donc d'articuler de telles evaluations avec celles qui sont faites pour les pollutions chroniques de l'eau et de l'air. La gestion du risque dans ces domaines se fait en effet selon une approche spatiale depuis longtemps: les deux exemples les plus nets sont les agences de bassin et les reseaux de surveillance et d'alerte pour la pollution de l'air. Parallelement a ces systemes de gestion, et souvent pour les besoins de leur fonctionnement, de nombreuses etudes ont ete effectuees sur des communautes urbaines et des regions, tant pour l'air que pour l'eau. L'autre objectif est de tirer parti des analyses faites sur les objets industriels, qui sont, a l'image de la gestion de leurs risques, sectorielles: industrie nucleaire, industrie petrochimique, transport de matieres dangereuses, pipeline etc.. Dans un premier temps, les trois angles d'attaque possibles du risque accidentel sont

  19. Modulação da pressão intracraniana em um modelo experimental de hipertensão abdominal e lesão pulmonar aguda

    OpenAIRE

    Zampieri,Fernando Godinho; Almeida,Juliana Roberta; Schettino,Guilherme Pinto de Paula; Park,Marcelo; Machado,Fabio Santana; Azevedo,Luciano Cesar Pontes

    2011-01-01

    OBJETIVO: Avaliar o efeito de alterações hemodinâmicas, respiratórias e metabólicas sobre a pressão intracraniana em um modelo de lesão pulmonar aguda e síndrome compartimental abdominal. MÉTODOS: Oito porcos Agroceres foram submetidos, após a instrumentação, a cinco cenários clínicos: 1) estado basal com baixa pressão intra-abdominal e pulmão sadio; 2) pneumoperitôneo, com pressão intra-abdominal de 20 mm Hg; 3) lesão pulmonar aguda induzida por lavagem pulmonar e desativação de surfactante;...

  20. The 'Pole Nucleaire Bourgogne' for developing the nuclear components industry

    International Nuclear Information System (INIS)

    Kottmann, G.

    2012-01-01

    The 'Pole Nucleaire Bourgogne' (PNB) is a high-technology and heavy industries cluster in Burgundy with an international calling. It aims at innovating, educating and federating in order to place the French nuclear industry in a leading position. PNB gathers 76 small-, and medium-sized enterprises, most of them operating in the metal sector, in design and in the control/measuring sector. The aim of PNB is to make enterprises work and cooperate on specific topics according to their sectors of activities and their skills. PNB has identified 3 domains of strategical innovations: -) ecological manufacturing and durability of heavy components, -) controls for high performance components, and -) maintenance and dismantling techniques in hostile environments. The various industry sectors represented in PNB allows a cross-fertilization between high-tech industries (aeronautics, energy, transportation)

  1. Quantitative measurements of small isotopic samples in gaseous mixtures by utilization of some nuclear properties; Etude des possibilites de mesures de faibles quantites de gaz radioactifs dans un melange en utilisant simultanement plusieurs proprietes nucleaires

    Energy Technology Data Exchange (ETDEWEB)

    Maragnon, J; Delperie, C

    1967-12-01

    The question is to define the characteristics of a group of measurements allowing the analysis of traces of radioactive rare gases in gas mixtures of different composition. To distinguish the radioactive isotopes from each other and the activity level reaching 10{sup 6} due to their nuclear properties, the method was chosen to use several nuclear properties: gamma radiation energy, beta particle energy, lifetime of excited states. The choice of a plastic scintillator as beta detector allows to answer satisfactorilly to this demand by measurement of nuclear constants because of the short de/excitation time of this detector. Another advantage is that it can be a reservoir for the sample without any destruction nor modification of the sample. The study has been based on the mixture of Kr-85, the analysis of other rare gases follwos immediately from the adopted principle. [French] Les auteurs ont oriente leur recherche vers une solution permettant de distinguer les isotopes radioactifs les uns des autres et dans des rapports d'activite pouvant atteindre 10{sup 6}, grace a plusieurs de leurs proprietes nucleaires, energie de rayonnement gamma, energie de la particule beta, temps de vie des niveaux excites. Le choix d'un scintillateur plastique comme detecteur beta permet de repondre d'une maniere satisfaisante a la mesure des constantes nucleaires en raison du temps de de/excitation rapide de ce scintillateur. Il offre en outre l'avantage de pouvoir servir de reservoir a l'echantillon sans entrainer aucune destruction ni modification de celui-ci. L'etude a ete basee sur la mixture de Kr-85, l'analyse des autre gaz rares decoulant immediatement du principe adopte. (auteur)

  2. Les jeux de hasard chez les enfants et les adolescents

    Science.gov (United States)

    Gupta, Rina; Pinzon, Jorge L

    2012-01-01

    RÉSUMÉ Même si, au Canada, les mineurs n’ont pas le droit de jouer à des jeux de hasard légalisés, les adolescents participent souvent à des jeux de hasard soit légalisés (produits de loterie, casino, terminaux de jeux vidéo), soit autonomes (jeux de cartes, paris sportifs, dés) à la maison et en milieu scolaire. Chez les adultes, le taux de prévalence de dépendance aux jeux de hasard au cours de la vie se situe entre 1 % et 2 %. D’après les données existantes, la prévalence chez les adolescents serait de deux à quatre fois plus élevée. On ne sait pas grand-chose des facteurs de risque d’apparition et de perpétuation d’une dépendance pathologique aux jeux de hasard. Le présent document de principes vise à informer les pédiatres, les médecins de famille et les autres professionnels de la santé des connaissances émergentes sur les jeux de hasard pendant l’enfance et l’adolescence et du risque de conséquences graves qui s’y rattachent. On y exhorte également les gouvernements fédéral, provinciaux et territoriaux à inclure cette question dans leur programme et à tenir compte des facteurs sociopolitiques associés aux jeux de hasard.

  3. Experimental contamination of margaritana margaritifera (L) (a Fresh water bivalve) by caesium 137; Contamination experimentale de margaritana margaritifera (L) (bivalve d'eau douce) par le cesium 137

    Energy Technology Data Exchange (ETDEWEB)

    Foulquier, L.; Bovard, P.; Grauby, A. [Commissariat a l' Energie Atomique, Cadarache (France). Centre d' Etudes Nucleaires

    1966-07-01

    The hydro biological research carried out in the Radio-Ecology Section has led the authors to study some Margaritana sampling stations situated down-stream from the Monts d'Arree nuclear power station. They describe the preservation and contamination methods used for fixing the {sup 137}Cs concentration factors in the case of Margaritana Margaritifera (L). The results of experiments carried out over a period of one hundred days show that the specific activity of the various organs is stabilized after thirty to thirty-five days. The authors have noticed a relatively low adsorption on the shell through the intermediary of micro-organisms, and a strong and rapid absorption in the soft parts. The concentration factors have values, at equilibrium, of around: 9 for the shell, 300 for all the organs, and 38 for the whole animal. A comparison of these results with work published by other authors makes it possible to draw general conclusions concerning the mechanism of {sup 137}Cs fixation by lamellibranch, as well as their capacity of fixation. (author) [French] Les etudes hydrobiologiques effectuees au sein de la Section de Radio-Ecologie ont amene les auteurs a etudier des stations de prelevement de Margaritana en aval de la Centrale Nucleaire des Monts d'Arree. Ils decrivent les methodes de conservation et de contamination utilisees pour l'etablissement des facteurs de concentration du {sup 137}Cs par Margaritana margaritifera (L). Les resultats des experimentations menees pendant cent jours montrent que les activites specifiques de la coquille et des differents organes se stabilisent au bout de trente a trente-cinq jours. Les auteurs constatent une adsorption relativement faible sur la coquille par l'intermediaire des micro-organismes et une absorption forte et rapide dans les parties molles. Les facteurs de concentration se situent, a l'equilibre, autour de: 9 pour la coquille, 300 pour l'ensemble des organes et 38 si l'on considere

  4. Staff Organization in Nuclear Power Stations; Organisation du personnel des centrales nucleaires; Organizatsiya personala na atomnykh ehlektrostantsiyakh; Organizacion del personal de las centrales nucleares

    Energy Technology Data Exchange (ETDEWEB)

    Scuricini, G. B. [Comitato Nazionale Energia Nucleare, Roma (Italy)

    1963-10-15

    This paper deals with the organization of operating and maintenance staff at nuclear power stations in Italy and manpower variations, either because the plants themselves differ or are organized in some special way. Staff doing jobs for which a specific training is required are given special consideration in the paper. (author) [French] Dans le memoire, on examine l'organisation du personnel d'exploitation et d'entretien des centrales nucleaires italiennes et les differences existant dans les effectifs, differences dues soit aux caracteristiques des centrales memes, soit aux particularites d'organisation des entreprises. Le personnel charge de fonctions determinees pour lesquelles un entrainement special est requis, fait l'objet d'une attention particuliere. (author) [Spanish] En la memoria se examina la organizacion del personal de explotacion y conservacion de las centrales nucleares italianas y las diferencias que existen entre sus efectivos, diferencias que se deben a las caracteristicas de las mismas centrales o a las particularidades de organizacion de las empresas. El autor dedica especial atencion al personal encargado de funciones que requieren una formacion profesional especial. (author) [Russian] Issleduyutsya voprosy organizatsii personala, zanimayushchegosya ehkspluatatsiej ital'yanskikh atomnykh ehlektrostantsij i ukhodom za nimi, a takkhe razlichiya v sostave personala, vytekayushchie libo iz kharakternykh osobennostej samikh stantsij, libo iz osobennostej organizatsii predpriyatij. Osoboe vnimanie udelyaetsya personalu, kotoromu porucheny opredelennye funktsii, trebuyushchie spetsial'noj pod go tovki. (author)

  5. Economic Criteria Applied to Nuclear Materials Management; Criteres Economiques Applicables a la Gestion des Matieres Nucleaires; Ehkonomicheskie kriterii, primenyaemye pri kontrole i uchete yadernykh materialov; Criterios Economicos Aplicados a la Administracion de Materiales Nucleares

    Energy Technology Data Exchange (ETDEWEB)

    Shelley, W. J.; Kuehn, M. N. [Mallinckrodt Chemical Works, St. Charles, MS (United States)

    1966-02-15

    placed upon such personnel to accept, understand and perform the work. Such personnel selected must be thoroughly and minutely trained in the importance of their activity. Those responsible for the management of nuclear materials must be continually alert to the smallest kind of aberration in the quality and performance of the personnel, the process, the systems, procedures and techniques. Only through such alertness and willingness to revise, so as to secure improvement, does one secure the optimum balance of costs and needs. (author) [French] La gestion des matieres nucleaires doit etre subordonnee aux objectifs principaux du traitement de ces matieres, c'est-a-dire la production d'energie ou la fabrication de produits finis. Les responsables de la gestion des matieres nucleaires doivent donc tenir constamment compte des besoins de la production principale et adapter les methodes de gestion aux operations de facon a pouvoir assurer cette gestion avec un minimum de depenses. Le systeme de gestion des matieres nucleaires doit soigneusement tenir compte des divers facteurs qui influent sur son prix de revient. Il vient en complement des operations et doit entrainer le minimum de frais de personnel et d'analyse et provoquer le moins d'interruptions possible dans les operations. U doit etre integre a ces dernieres, de facon que les renseignements d'ordre quantitatif qu'il permet d'obtenir puissent etre communiques rapidement aux responsables du controle des operations. Le systeme d'enregistrement et de preparation des rapports doit fournir une quantite maximale de donnees subsidiaires. Il doit etre compatible avec les systemes utilises par les fournisseurs et les consommateurs et assurer la diffusion, partout ou cela est possible, de renseignements supplementaires concernant les lots de matieres nucleaires. Les donnees a fournir pour le controle des matieres nucleaires doivent se limiter a celles qui sont necessaires pour s'assurer qu'il n'y a pas de pertes importantes, de

  6. Contribution to the study of radio toxicity of aromatic and medicinal plants using solid state nuclear track detectors; Contribution a l etude de la radio toxicite des plantes aromatiques et medicinales au moyen des detecteurs solides de traces nucleaires

    Energy Technology Data Exchange (ETDEWEB)

    Mortassim, A; Misdaq, M A; Naaman, A

    2009-07-01

    The concentrations of uranium (238 U), thorium (232 Th), radon (222 Rn) and thoron (220 Rn) were measured in twenty aromatic and medicinal plants in {sup f}ind a new method based on using solid state nuclear track detectors type Cr-39 and Rs-115. He emerges from this study that the verbena and salvia have higher levels of uranium (radon) higher than that of other plants while the leaves of olive and saturja have concentrations of thorium (thoron) higher than other plants therefore radio toxicity of these plants is higher than that of others and may pose a radiological hazard if the masses are incorporated by consumers high. [French] Les concentrations en uranium (238U), thorium (232Th), radon (222Rn), et thoron (220Rn) ont ete mesurees dans vingt plantes aromatiques et medicinales en utilsant une nouvelle methode basee sur l utilisation des detecteurs solides de traces nucleaires de types CR-39 et LR-115. Il en sort de cette etude que la verveine et la salvia presentent des teneurs en uranium (radon) superieurs a celle des autres plantes alors que les feuilles d olivier et la saturja presentent des concentrations en thorium (thoron) plus elevee que celles des autres plantes par consequent la radio toxicite de ces plantes est superieure a celles des autres et peuvent presenter un risque radiologique si les masses incorporees par les consommateurs sont elevees.

  7. Irradiation and development of the nuclear emulsions exposed to intense fluxes of thermal neutrons with {gamma} rays; Irradiation et developpement des emulsions nucleaires exposees a des flux intenses de neutrons thermiques, accompagnes de rayons {gamma}

    Energy Technology Data Exchange (ETDEWEB)

    Faraggi, H.; Bonnet, A.; Cohen, J. [Commissariat a l' Energie Atomique, Lab. du Fort de Chatillon, Fontenay-aux-Roses (France). Centre d' Etudes Nucleaires

    1952-07-01

    The thermal neutron fluxes provided by nuclear reactors permit the survey of relatively rare phenomenons, and dosage of very weak quantities of some elements. One of the most favorable detection technique are constituted by the use of the nuclear emulsions. one can mention: - the dosage of uranium by counting in the emulsion the number of traces due to fission fragments after irradiation. - The dosage of the lithium and the boron as trace amounts with the help of nuclear reactions (n, {alpha}) and thermal neutrons. - The research of reactions (n, {alpha}) or (n, p) of very weak cross section for middle or heavy elements. These different applications require however important neutrons fluxes. It had therefore obliged us to search for the most favorable irradiation and development of the emulsions conditions, to get the best visibility of the trajectories and decrease the phenomena of fog on the emulsion, which prevents any observation. (M.B.) [French] Les flux de neutrons thermiques fournis par les reacteurs nucleaires permettent l'etude de phenomenes relativement rares, et le dosage de tres faibles quantites de certains elements. Un des moyens de detection les plus favorables est constitue par l'utilisation des emulsions nucleaires. on peut citer: - le dosage de l'uranium par comptage dans l'emulsion du nombre de traces dues aux fragments de fission apres irradiation. - Le dosage du lithium et du bore a l'etat de traces a l'aide des reactions (n, {alpha}) sous l'action des neutrons thermiques. - La recherche de reactions (n,{alpha}) ou (n,p) de tres faible section efficace pour des elements moyens ou lourds. Ces differentes applications necessite cependant des flux de neutrons important. On a donc ete amene a rechercher les conditions les plus favorables d'irradiation et de developpement des emulsions, de maniere a obtenir la meilleure visibilite des trajectoires et diminuer les phenomenes de voile de l'emulsion, qui

  8. SCPRI Emergency Kit for Use in the Event of a Nuclear Accident; Le Dispositif d'Intervention Rapide du SCPRI en Cas d'Accident Nucleaire

    Energy Technology Data Exchange (ETDEWEB)

    Ervet, P.; Moroni, J. P.; Pellerin, P. [Service Central de Protection Contre les Rayonnements Ionisants, Ministere des Affaires Sociales, Le Vesinet (France)

    1969-10-15

    In the event of a nuclear accident necessitating implementation of the ORSEC radiation protection plan, the Service central de protection contre les rayonnements ionisants (Central Service for Protection against Ionizing Radiations), in conjunction with the Service national de la protection civile (National Civil Defence Service), has adopted the necessary measures for rapid evaluation of possible contamination as promptly as possible. With this aim in mind the Service has prepared emergency kits, which are permanently stored at airfields in the Paris region; these can be carried by aircraft together with two engineers from the Service, thereby enabling them to reach the site of the incident with the specialized equipment in a few hours at most. This paper describes the monitoring and sampling equipment as well as the conditions under which the kit is carried and used (it operates independently by having a built-in generating unit). It is basically designed to permit an initial assessment of the situation, to furnish local authorities with data on which to base decisions for the safety of the population, and to determine any additional measures that need to be adopted. (author) [French] Dans le cas d'un accident nucleaire impliquant la mise en application du plan ORSEC radiologique, en liaison avec le Service national de la protection civile, le Service central de protection contre les rayonnements ionisants a pris les dispositions necessaires pour faire une evaluation rapide, aussi preooce que possible, des contaminations eventuelles. Dans ce but, il a realise des cantines d'intervention qui sont deposees en permanence sur les aerodromes de la region parisienne, et peuvent etre embarquees par avion avec deux ingenieurs du service qui peuvent etre ainsi sur les lieux de l'incident, avec un materiel specialise, dans un delai qui n'excede pas quelques heures. Le memoire decrit le materiel de mesure et de prelevement, ainsi que les conditions de transport et d

  9. The Use of the Moessbauer Effect in Investigating the Chemical Effects of Nuclear Transmutations in Oxygenous Compounds of Manganese and Tin; Utilisation de l'Effet Moessbauer pour l'Etude des Effets Chimiques des Transformations Nucleaires dans les Composes de Manganese et d'Etain; 0418 0421 0421 041b 0415 0414 ; Empleo del Efecto Moessbauer para Investigar las Transformaciones Nucleares de Compuestos Oxigenados de Estano y de Manganeso

    Energy Technology Data Exchange (ETDEWEB)

    Nesmejanov, An. N.; Babeshkin, A. M.; Kosev, N. P.; Bekker, A. A.; Lebedev, V. A. [Moskovskij Gosudarstvennyj Universitet Im. M.V. Lomonosova, Moskva, SSSR (Russian Federation)

    1965-04-15

    The customary methods of studying the chemical state of recoil atoms, i. e. those connected with phase transitions (chemical analysis, chromatography, electrophoresis) and also the annealing technique, permit only indirect judgments as to the stabilization mechanism of hot atoms. In analysis with the method of resonance absorption of non-recoil gamma-quanta, no changes are introduced into the sample that could influence the forms of stabilization, even where stability is not very great. In the present study we investigated the forms of stabilization of Mn56 recoil atoms in irradiated solutions and solid samples of permanganate, and of Sn{sup 119m} recoil atoms in stannic oxide and stannous oxide. The permanganate samples were irradiated in a paraffin block with a polonium-beryllium source at a neutron flux of 10{sup 7} - 10{sup 8} n/cm{sup 2}. s. The hot Mn{sup 56} atoms are formed in the +7, +4 and lower valency states. From samples (SnO and SnO{sub 2}) irradiated in a reactor for 1800 h at a flux of 2.2 x 10{sup 13} n/cm{sup 2}. s, sources were prepared directly for a study of the resonance absorption of gamma-quanta in an apparatus operating at constant speed. Suitable compounds of tin were used as absorbers. The Sn{sup 119m} recoil atoms were detected only in the +4-valency state. The data obtained are taken as the basis for a discussion of the stabilization mechanism of recoil atoms. (author) [French] Les methodes habituellement appliquees pour etudier l'etat chimique des atomes de recul (analyse chimique, chromatographie, electro- phorese) sont liees, comme le recuit, aux transitions de phases et ne permettent de determiner le mecanisme de stabilisation des atomes chauds que d'une facon indirecte. Lorsque l'analyse est faite au moyen d'une methode fondee sur l'absorption par resonance des phonons sans recul, l'echantillon ne subit aucune modification pouvant exercer une influence sur les formes de stabilisation, meme si ces formes sont peu durables. Les

  10. Lesão pulmonar de reperfusão por oclusão da aorta abdominal: modelo experimental em ratos

    Directory of Open Access Journals (Sweden)

    PINHEIRO BRUNO DO VALLE

    2000-01-01

    Full Text Available Introdução: Procedimentos cirúrgicos com oclusão da aorta têm sido associados a lesão pulmonar de reperfusão. O objetivo deste trabalho foi estudar a presença de edema pulmonar em um modelo de lesão de reperfusão por oclusão da aorta em ratos. Material e métodos: 33 ratos Wistar foram anestesiados com tiopental sódico (20mg/kg, via intraperitoneal, seguindo-se laparotomia por incisão mediana, para isolamento da aorta e cava inferior. A seguir, os animais foram randomizados em três grupos. Grupo isquemia-reperfusão (GIR, n = 5: animais submetidos a 30min de oclusão dos vasos, seguindo-se 120min de reperfusão. Grupo isquemia (GI, n = 5: animais submetidos a 30min de oclusão dos vasos. Grupo controle (GC, n = 5: animais submetidos apenas ao procedimento cirúrgico, sem oclusão dos vasos, acompanhados por 150min. Após o sacrifício, em 15 animais foram realizados estudos histopatológicos dos pulmões. Para caracterização de edema, foi realizada a análise morfométrica por contagem de pontos, determinando-se o índice de edema alveolar. Realizou-se também uma análise semiquantitativa da infiltração de polimorfonucleares nos pulmões. Em 18 animais retirou-se o pulmão direito para a determinação da relação entre os pesos úmido e seco. O índice de edema alveolar e a relação peso úmido/peso seco foram comparados entre os grupos através de ANOVA, com a correção de Bonferroni para comparação entre os grupos dois a dois. Resultados: Os animais do GIR apresentaram maior edema alveolar em relação aos do GI e GC (0,24; 0,18; 0,17; respectivamente, com p < 0,001. Não houve diferenças nas relações peso úmido/peso seco dos três grupos. Houve maior infiltração de células inflamatórias nos pulmões dos ratos submetidos a isquemia-reperfusão. Os autores concluem que a oclusão e desoclusão da aorta infra-renal está associada à lesão pulmonar. Essa lesão não foi induzida pela elevação da press

  11. Etude expérimentale des phénomènes de coalescence dans les systèmes bulles-gouttes Experimental Study of Coalescence Phenomena in Bubble-Drop Systems

    Directory of Open Access Journals (Sweden)

    Roques H.

    2006-11-01

    Full Text Available A l'occasion d'une étude sur les séparations eau-hydrocarbures par flottation, nous avons été amenés à étudier expérimentalement les coalescences bulle-goutte, goutte-goutte et bulle-bulle dans le système triphasique eau-air-kérosène. Les 4 montages expérimentaux décrits nous ont permis d'étudier les aspects statiques (structure du complexe bulle-goutte qui se forme et dynamiques (temps de coalescence moyens bulle-goutte, goutte-goutte et bulle-bulle et d'étudier l'influence de composés transférables d'une phase à l'autre sur ces temps de coalescence moyens. Du point de vue statique, la configuration stable du complexe bulle d'air-goutte de kérosène correspond à la formation à l'interface eau-air d'un film d'hydrocarbure qui entoure la bulle d'air, Par contre, la fixation d'une bulle d'air à la périphérie d'une goutte de kérosène, selon la disposition classique dans la flottation des solides, ne s'observe ici que rarement et toujours de façon transitoire. D'un point de vue cinétique on observe que : - les coalescences bulle-bulle ou goutte-goutte sont toujours favorisées (les temps de coalescence moyens diminuent lorsqu'on introduit dans la phase gaz ou dans l'une des phases liquides un composé transférable dans l'autre phase liquide; - les coalescences bulle-goutte sont favorisées par la présence dans la phase gaz d'un composé transférable dans la phase continue aqueuse ou par la présence dans la phase dispersée liquide d'un composé transférable dans la phase continue aqueuse; - les coalescences bulle-goutte sont défavorisées par la présence dans la phase continue aqueuse d'un composé transférable sur les gouttes constituant la phase dispersée liquide. During a study of water-hydrocarbon separations by flotation, we were led to make an experimental examination of bubble-drop, drop-drop and bubble-bubble coalescences in a three-phase water-air-kerosene system. The four experimental arrangements

  12. Jeux chez les Touaregs

    OpenAIRE

    Bernus, E.

    2012-01-01

    Parmi les jeux pratiqués par les Touaregs, il faut distinguer les jeux sportifs qui opposent deux équipes ou deux hommes, des jeux de société dans un cadre inscrit dans le sable, et les jeux d’esprit, véritables joutes verbales ; enfin, il faut signaler la construction par les enfants de jouets. Un certain nombre de jeux sont connus chez d’autres populations africaines. L’ouvrage de Charles Béart, Jeux et jouets de l’Ouest africain (1955), nous permet d’utiles comparaisons. Il est donc intére...

  13. Les risques du travail

    CERN Document Server

    Thébaud-Mony, Annie

    2015-01-01

    Depuis les années 1990, les conditions de travail se sont peu à peu imposées dans le débat social. Néanmoins, la situation reste critique. Les risques traditionnels n'ont pas disparu : les manutentions lourdes, l'exposition professionnelle aux cancérogènes, au bruit ou aux vibrations demeurent répandues... De plus, certaines " améliorations " n'ont fait que déplacer et dissimuler les problèmes, telle l'externalisation des risques grâce à la sous-traitance. Dans le même temps, les transformations du travail et des modalités de gestion de la main-d'œuvre ont fragilisé les collectifs et accru l'isolement des salariés, conduisant à une montée visible de la souffrance psychique. Face à ces évolutions, il est plus que jamais nécessaire que tous les acteurs concernés, en particulier les salariés eux-mêmes et leurs représentants, s'approprient les connaissances indispensables pour améliorer la protection de la santé sur les lieux du travail. Tel est le but de ce livre, qui renouvelle int�...

  14. Contribution to the study of {beta} disintegration and of nuclear structure using experiments on certain {beta}-{gamma} cascades: 198{sub Au}, 86{sub Rb}, 170{sub Tm}; Contribution a l'etude de la desintegration beta et a l'etude de la structure nucleaire a l'aide d'experiences sur certaines cascades beta-gamma: 198{sub Au}, 86{sub Rb}, 170{sub Tm}

    Energy Technology Data Exchange (ETDEWEB)

    Lachkar, J. [Commissariat a l' Energie Atomique, Bruyeres-le-Chatel (France). Centre d' Etudes; Paris-11 Univ., fabulte des Sciences 91 - Orsay (France)

    1969-07-01

    {beta}{gamma} directional angular correlations and shapes of inner beta spectra leading to the first excited level of the final nucleus enable one to determine the nuclear matrix elements typical of the {beta} transition. In the three observed first forbidden cases: {sup 170}Tm, {sup 86}Rb, {sup 198}Au, these matrix elements do not confirm the independent shell model theory. Other hypotheses are then suggested and discussed. (author) [French] Les experiences de correlation angulaire {beta}{gamma} et l'etude du spectre {beta} conduisant au premier niveau excite du noyau final permettent de determiner les elements de matrices nucleaires caracteristiques de cette transition. Dans les trois cas etudies (transitions une fois interdites): {sup 170}Tm, {sup 86}Rb, {sup 198}Au, ces elements de matrices ne peuvent etre retrouves a l'aide du modele en couches et a particules independantes. D'autres hypotheses sont alors emises et discutees. (auteur)

  15. Contribution to the study of {beta} disintegration and of nuclear structure using experiments on certain {beta}-{gamma} cascades: 198{sub Au}, 86{sub Rb}, 170{sub Tm}; Contribution a l'etude de la desintegration beta et a l'etude de la structure nucleaire a l'aide d'experiences sur certaines cascades beta-gamma: 198{sub Au}, 86{sub Rb}, 170{sub Tm}

    Energy Technology Data Exchange (ETDEWEB)

    Lachkar, J [Commissariat a l' Energie Atomique, Bruyeres-le-Chatel (France). Centre d' Etudes; Paris-11 Univ., fabulte des Sciences 91 - Orsay (France)

    1969-07-01

    {beta}{gamma} directional angular correlations and shapes of inner beta spectra leading to the first excited level of the final nucleus enable one to determine the nuclear matrix elements typical of the {beta} transition. In the three observed first forbidden cases: {sup 170}Tm, {sup 86}Rb, {sup 198}Au, these matrix elements do not confirm the independent shell model theory. Other hypotheses are then suggested and discussed. (author) [French] Les experiences de correlation angulaire {beta}{gamma} et l'etude du spectre {beta} conduisant au premier niveau excite du noyau final permettent de determiner les elements de matrices nucleaires caracteristiques de cette transition. Dans les trois cas etudies (transitions une fois interdites): {sup 170}Tm, {sup 86}Rb, {sup 198}Au, ces elements de matrices ne peuvent etre retrouves a l'aide du modele en couches et a particules independantes. D'autres hypotheses sont alors emises et discutees. (auteur)

  16. A future for nuclear sites beyond their service life. Nuclear site value development; Un avenir pour les sites nucleaires en fin de cycle. Valorisation des sites nucleaires

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2008-07-01

    As the nuclear industry moves into a new development phase, many facilities built in the fifties and sixties are reaching the end of their service life. Dismantling them and rehabilitating the sites on which they stand is a major industrial challenge which will give rise to a number of new projects. AREVA has more than 20 years' experience in these highly technical fields. As more and more sites reach the end of their service life, AREVA considers nuclear site value development as a fully-fledged industrial activity. The group's competencies in this field have been grouped together to form a dedicated entity: the Nuclear Site Value Development Business Unit, created in 2008. Several billion euros are invested in site value development projects which are far-reaching and complex, and often last for several decades. Long before work actually begins, lengthy studies and preparations are required to schedule operations, select the techniques to be used and optimize costs and deadlines. The Nuclear Site Value Development BU is currently working on four major projects involving its own facilities and those of the CEA: - La Hague: dismantling of the first generation of used fuel recycling facilities. Between 1966 and 1998, almost 5,000 tons of used fuel from graphite-moderated gas-cooled reactors, 4,500 tons of light water reactor fuel, as well as fuel from fast reactors and research reactors, were treated at UP2 400, the very first industrial recycling plant on the La Hague site. - Marcoule: first-time dismantling of a recycling plant. 1,000 rooms to be cleaned up, 30,000 tons of waste to be treated, 30 years of work. - Cadarache: first-time dismantling of a Mox fuel fabrication plant. The Cadarache plant was commissioned in 1962 to fabricate fuel for fast reactors; this was followed by MOX fuel for light water reactors, an activity which continued until the plant was shut down in 2003. - Annecy and Veurey: giving a new lease of life to former industrial sites in built-up areas. AREVA is currently working on a site value development program on two industrial sites in Annecy and Veurey, near Grenoble. Dating back to 1955 and 1957, the sites were created for the manufacture and precision machining of uranium metal. The number of clean-up and dismantling projects is set to rise steadily in the years ahead and site value development will unquestionably become a new nuclear activity in its own right. AREVA is developing the corresponding competencies and expertise: new professions are springing up (value development project manager, scenario and feedback manager, operational dismantling methods manager, flushing operator, etc.) and a dedicated theoretical and practical training program is being put together. Once a nuclear site has been shut down, the long-term dismantling and value development operations make a considerable contribution to the local economy. Site rehabilitation is an environmental necessity and improves nuclear's image in the eyes of the public. As new nuclear projects get off the ground, developing the value of disused sites will free up space for future projects and make a valuable contribution to the nuclear revival.

  17. Determination of radioactive risks connected with the working of a nuclear plant; Evaluation des risques radioactifs lies au fonctionnement d'une installation nucleaire

    Energy Technology Data Exchange (ETDEWEB)

    Lavie, J M; Doury, A [Commissariat a l' Energie Atomique, Saclay (France).Centre d' Etudes Nucleaires

    1960-07-01

    Numerous problems which are posed by the evaluation of the radioactive risks linked to the working of a nuclear plant are new problems which have not yet been satisfactorily solved. In these conditions this study must be considered only as a preliminary approach whose essential aims are the following: - development and synthesis of the existing data; - rapid determination of conservative and usable orders of greatness for the security factors, both for normal working and in the case of an accident. The most probable typical accidents are reviewed together with the nature of the resulting risks and the principal factors on which these risks depend. Among these factors, one of the most important is atmospheric diffusion which is studied in some detail using the analytic model due to Sutton. A logical graphical presentation increasing the flexibility in the use of the results and presents the responsible authorities with a flexible, practical and rapid means of evaluating the risks involved starting from a sufficiently general system of initial and simultaneously valid conditions (types of accident, atmospheric conditions). (author) [French] De nombreux problemes souleves par l'evaluation des risques radioactifs lies au fonctionnement d'une installation nucleaire sont des problemes nouveaux qui n'ont pas encore recu de solution satisfaisante. Dans ces conditions cette etude ne doit etre consideree que comme une premiere approche dont les objectifs essentiels sont les suivants: - mise au point et synthese de donnees existantes; - determination rapide d'ordres de grandeur conservatifs et utilisables de valeurs de securite, tant en fonctionnement normal qu'en cas d'accident. Les accidents types les plus probables sont passes en revue ainsi que la nature des risques qui en decoulent et les principaux facteurs dont dependent ces risques. Parmi ces facteurs, l'un des plus importants est la diffusion atmospherique qui fait l'objet d'une etude particuliere a l'aide du modele

  18. The design and construction of a nuclear free-precession magnetometer; Etude et realisation d'un magnetometre a precession libre nucleaire

    Energy Technology Data Exchange (ETDEWEB)

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

    1960-10-15

    After presenting the advantages of nuclear magnetic resonance with respect to electromagnetic processes, as far as the measurement of the earths' magnetic field is concerned, we deal with the macroscopic theory for the Bloch model and analyse Packard and Varions' experiment. The development of a particular absolute free-precession magnetometer is studied, and the conditions are determined for obtaining a maximum amplitude signal as a function of the geometrical form of the detector coil, of the method of cut-off, and of the coupling between various parts of the system. After having described in detail the technology of amplifiers, we consider the problem of the measurement of the frequency of precession for which an original solution, of analogy form, is proposed and discussed. Complete plans of the equipment are given in an appendix. (author) [French] Apres avoir presente les avantages de la resonance magnetique nucleaire relativement aux procedes electromagnetiques, en ce qui concerne la mesure du champ magnetique terrestre, on traite de la theorie macroscopique dans le modele de Bloch et analyse l'experience de Packard et Varian. On etudie une realisation particuliere d'un magnetometre absolu a precession libre et determine les conditions d'obtention d'un signal d'amplitude maximale en fonction de la forme geometrique du bobinage detecteur, de la methode de coupure, et du couplage entre les differents elements du montage. Apres avoir decrit en detail la technologie des amplificateurs, on aborde le probleme de la mesure de la frequence de precession, pour laquelle une solution originale, sous forme analogique, est proposee et discutee. En annexe est joint un dossier complet des plans de la realisation. (auteur)

  19. Some aspects of the nuclear fission process; Quelques aspects du processus de fission nucleaire

    Energy Technology Data Exchange (ETDEWEB)

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

    1961-07-01

    In the following report one can find first a short general view on the present situation of our knowledge concerning the nuclear fission process, namely on the nucleus going through the saddle-point. Then there are some aspects connected with the excitation energy of the fissioning nucleus. The measurements made at Saclay on the fast neutron fission cross-section of U{sup 233}, U{sup 235}, Pu{sup 239}, U{sup 238} are described at the beginning of this work. It appears that for U{sup 233} there is some characteristic shape modulation of the cross-section curve, in relation with the collective excited state of the deformed nucleus at the saddle-point. Good evidence of this is also given by the study of the relative fission rate with emission of long-range particles; it appears also that this ternary fission rate does not change substantially for neutron between thermal energy and 2 MeV, but that is very lower for the compound nucleus U{sup 239} than for even-even compound nuclei. At the end there are some experiments on the strong 4,5 MeV gamma-ray originated by slow neutron absorption in U{sup 235}. Time-of-flight device is used to establish that this 4,5 MeV gamma-ray seems mostly connected with radiative capture. (author) [French] Le present travail debute par un apercu de l'etat actuel de nos connaissances sur le processus de fission nucleaire, notamment sur le passage par le point-seuil. Puis sont evoques des aspects lies au niveau d'energie d'excitation auquel est porte le noyau qui subit la fission. Les mesures de sections efficaces de fission induite dans {sup 233}U, {sup 235}U, {sup 239}Pu et {sup 238}U par des neutrons rapides effectuees a Saclay sont decrites en premier lieu; elles font apparaitre pour {sup 233}U une ondulation caracteristique du role des etats collectifs d'excitation du noyau deforme au point-seuil. Des experiences sur la fission avec emission de particules de long parcours confirment cet aspect tout en demontrant que la frequence

  20. Repercussões respiratórias e hemodinâmicas do pneumoperitônio na lesão do diafragma: estudo experimental Hemodynamic and respiratory changes caused by CO2 laparoscopy in an experimental model of diaphragmatic injury

    Directory of Open Access Journals (Sweden)

    Sílvia Cristine Soldá

    2007-08-01

    Full Text Available OBJETIVO: Analisar as alterações hemodinâmicas e respiratórias secundárias à laparoscopia em modelo experimental de lesão diafragmática. MÉTODOS: Foram utilizados 15 suínos, distribuídos em três grupos com cinco animais cada, assim constituídos: Grupo 1 - Portadores de lesão diafragmática e avaliados sem pneumoperitônio (CLSP; Grupo 2 - Sem lesão diafragmática e avaliados com pneumoperitônio (SLCP; Grupo 3 - Portadores de lesão diafragmática e avaliados com pneumoperitônio (CLCP. Foram avaliadas variáveis gasométricas, hemodinâmicas e respiratórias. RESULTADOS: Houve alterações significantes da pressão média de artéria pulmonar (PAP, pressão de capilar pulmonar (PCP, PAO2, SAO2 e SVO2. CONCLUSÃO: A videolaparoscopia na presença de lesão do diafragma não acarreta alterações do débito cardíaco e pode ser realizada com segurança, desde que a pressão de pneumoperitônio não ultrapasse valores de 15 mmHg.OBJECTIVE: The objective of this study was to analyze the hemodynamic and respiratory changes caused by CO2 laparoscopy in an experimental model of diaphragmatic injury. METHODS: Fifteen animals chosen at random were submitted to diaphragmatic injury by means of CO2 laparoscopy. Evaluation consisted of drawing blood samples to analyze blood gases, as well as the hemodynamic and respiratory variables. RESULTS: Alterations occurred in APA, CPP, PAO2, ASO2, VSO2. CONCLUSION: We concluded that videolaparoscopy with pneumoperitoneum pressure under 15mmHg is a safe procedure in patients with diaphragmatic injuries because this pressure level does not cause hemodynamic changes, such as decrease of the cardiac output. [Rev Assoc Med Bras 2007; 53(4: 294-9

  1. Excision Les jeunes changent l'Afrique par les TIC

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

    Comité Inter-Africain sur les Pratiques Traditionnelles ayant effet sur la santé des ... Planche 7 - Perception genrée de la citoyenneté : les dire des femmes. 90 ...... dans le monde avec les migrations internationales, l'excision ne semble pas être ...... En utilisant les TIC pour exprimer leurs attentes et leurs besoins, les jeunes, ...

  2. Influência do antibiótico nas lesões de isquemia e reperfusão intestinal: estudo experimental em ratos The influence of antibiotics on intestinal ischemia and reperfusion: experimental study in rats

    Directory of Open Access Journals (Sweden)

    Maria de Lourdes Pessole Biondo-Simões

    2000-01-01

    Full Text Available Muito se tem questionado sobre os efeitos da isquemia intestinal seguida de reperfusão (I/R, chamando a atenção para o papel dos leucócitos na patobiologia da I/R. A fisiopatogenia das lesões está intimamente ligada à geração de radicais de oxigênio durante o período em que se processa a reperfusão. A ruptura da barreira intestinal permitindo a translocação bacteriana agravaria ainda mais estas lesões. Este estudo tem por objetivo avaliar as lesões intestinais na vigência de isquemia e na reperfusão com e sem antibioticoterapia. Submeteram-se 42 ratos Wistar à anestesia e laparotomia mediana. Obteve-se isquemia intestinal por clampeamento das artérias mesentéricas cranial e caudal por 30 minutos. Após reperfundiu-se por igual tempo. Metade destes animais receberam 50 mg/kg de eritromicina por via oral nas 24 horas que antecederam o procedimento. Cada um destes grupos foi subdividido em outros 3, constituíndo os subgrupos de controle, isquemia e isquemia/reperfusão. Ao final, ressecaram-se segmentos do intestins delgado para processamento histológico. Avaliaram-se os resultados pela escala de CHIU e col. e submeteram-se os resultados à tratamento estatístico. Observou-se que a mucosa intestinal apresentava-se com padrão normal nos grupos de controle, tanto com antibioticoprofilaxia como sem. Os intestinos submetidos à isquemia com ou se antibioticoprofilaxia mostraram, lesões com descolamento e perda de vilosidades até infartamento transmucoso. Os intestinos reperfundidos apresentavam lesões semelhantes. Verificou-se que os intestinos reperfundidos que receberam antibioticoprofilaxia apresentavam lesões mais graves do que os que sofreram isquemia sem antibioticoprofilaxia (p=0,0303. Concluiu-se que o uso de antibióticos pré-isquemia não diminui a gravidade das lesões histopatológicas da mucosa intestinal, não protegendo das lesões após a reperfusão.The role of the white blood cells in the ischemia and

  3. Avaliação da atividade hepatoprotetora do asiaticosídeo em modelo experimental de lesão hepática por paracetamol em ratos

    Directory of Open Access Journals (Sweden)

    Gustavo Henrique da Silva

    2014-08-01

    Full Text Available O asiaticosídeo é um triterpenóide presente no extrato da Centella asiatica, sendo responsável pela atividade terapêutica desta planta em doenças hepáticas crônicas. O hepatócito é a célula responsável pelas funções endócrinas e exócrinas do fígado, além de converter substâncias nocivas em materiais não tóxicos excretados pela bile. Por esse motivo, o fígado é sensível à ação de alguns fármacos, como, por exemplo, o paracetamol. Assim, utilizando o paracetamol como modelo experimental de lesão hepática, o objetivo deste estudo foi avaliar a ação hepatoprotetora do asiaticosídeo, na dose estabelecida como terapêutica, em ratos Wistar. Dois grupos compostos por vinte animais cada, tratados com asiaticosídeo (1mg/kg/dia v.o. por oito dias e não tratados foram submetidos à intoxicação com elevada dose de paracetamol (3 g/kg v.o no oitavo dia. Em seguida, os animais foram eutanasiados após 24 h ou 72 h para coleta de amostras de sangue e fragmentos de fígado. Para avaliação da atividade hepatoprotetora, foi realizada a dosagem sérica de enzimas indicativas de lesão hepática (AST, ALT e Fosfatase Alcalina e a análise histológica e morfométrica do tecido hepático. Os resultados obtidos permitiram evidenciar que na dose utilizada, o asiaticosídeo apresenta atividade hepatoprotetora, uma vez que o grupo submetido ao tratamento prévio apresentou menos lesões histológicas e menores níveis séricos de AST e ALT quando comparado ao grupo controle. Estes resultados permitem concluir que o asiaticosídeo, na dose mais usualmente empregada na fitoterapia, apresentou atividade hepatoprotetora na hepatite aguda causada por elevada dose de paracetamol.

  4. Les outils du CERN

    CERN Multimedia

    1999-01-01

    C'est le plus grand centre mondial de recherche en physique des particules. Les outils du Laboratoire, accélérateurs et détecteurs de particules, figurent parmi les instruments scientifiques les plus complexes au monde. Des prix Nobels ont d'ailleurs été attribués aux physiciens du CERN pour leurs développements.

  5. Les Malalties dels cereals

    OpenAIRE

    Puiggrós i Jové, Josep Maria

    1989-01-01

    En aquest treball es fa una descripció de les principals malalties dels cereals que han estat trobades a Catalunya. Agrupant-les segons ataquin la fulla i espiga: oïdi, rovells, septòries, Rhynchosporium, Helminthosporium, i virus; al coll i tija: Cercosporella, Ophiobolus, Rhizoctbnia i Fusarium o bé les que vénen de la llavor: carbons, càries i Helminthospbrium. A part de la descripció, hom fa esment de les observacions efectuades els darrers anys en els diferents indrets de...

  6. Practical guide to dosimetry as applied in the research reactors of the Saclay and Grenoble nuclear research centers; Guide pratique de la dosimetrie mise en oeuvre dans les reacteurs de recherche du C.E.N./G et du C.E.N./S

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1968-07-01

    Since the problems concerning neutron and gamma flux measurements which arise during irradiation experiments in the reactors in the Grenoble and Saclay Centres are of the same type, and since the solutions found are very often adopted in common, we have attempted to describe the methods we use at the present time. A brief description is given of the production of the detectors, the electronic apparatus; the formulae usually used for the interpretation of the measurements are given. A series of technical data cards give the most commonly used detector characteristics. These cards give the physical characteristics of the detectors, their nuclear constants, if any, the most suitable counting methods and the field of application. (authors) [French] Les problemes de mesures de flux de neutrons et de flux gamma qui se posent pour les experiences irradiees dans les reacteurs des Centres de Grenoble et de Saclay etant du meme type et les solutions trouvees, tres souvent adoptees en commun, nous avons cherche a decrire les methodes que nous pratiquons actuellement. On decrit tres brievement la fabrication des detecteurs, l'appareillage electronique; on rappelle les formules usuelles qui servent dans l'interpretation des mesures. Une serie de fiches techniques rassemble les caracteristiques des detecteurs les plus couramment utilises. Ces fiches indiquent les caracteristiques physiques des detecteurs, leurs constantes nucleaires s'il y a lieu, les methodes de comptage les mieux adaptees et le domaine d'utilisation. (auteurs)

  7. Study methods for the drillings around the underground nuclear explosions in the Sahara. Part 1. study of rock samples; Methodes d'etude des forages realises autour des explosions nucleaires souterraines au Sahara. Premiere partie: etude des echantillons de roche

    Energy Technology Data Exchange (ETDEWEB)

    Derlich, S [Commissariat a l' Energie Atomique, Bruyers-le-Chatel (France). Centre d' Etudes

    1969-07-01

    An examination of the mechanical effects produced on rocks by an underground nuclear explosion calls for the use of particular means of exploration which are described in this report, special attention being paid to the equipment used in connection with the French nuclear tests in the Sahara. The drilling methods used (rotary and turbo-drilling) are adapted to the particular conditions of the sampling programme, to the radioactivity and to the temperature in the region of the explosion. A study of the samples makes it possible to obtain the new characteristics of the rock and to assess the chemical and mechanical transformations which it has undergone. An examination of the core obtained from the drilling, together with a knowledge of the drilling parameters (depth of the probe, sample recovery, etc...), makes it possible to study the extent and the characteristics of the zones which have been damaged to different degrees according to their distance from the zero point: cavity, strongly powdered zone, fractured zone, chimney, zones containing high stresses leading to a particular type of fracture of the cores. The problems connected with the interpretation of the results are also presented. (author) [French] L'examen des effets mecaniques provoques par une explosion nucleaire souterraine sur la roche necessite la mise en oeuvre de moyens d'exploration particuliers dont l'expose fait l'objet de ce rapport, essentiellement pour les moyens utilises autour des essais nucleaires francais au Sahara. Les methodes de forage (rotary et turboforage) sont adaptees aux conditions particulieres dues au programme d'echantillonnage, a la radioactivite et a la temperature regnant a proximite du point de tir. L'etude des echantillons permet la determination des nouveaux caracteres de la roche et de ses transformations chimique et mecanique. L'examen des carottes et l'utilisation des parametres de forage (cotes sondeurs, recuperation des echantillons, etc...) permettent d'etudier l

  8. Les trous noirs

    CERN Document Server

    Ioli, Elena

    2016-01-01

    L'univers est peuplé par des étoiles, des planètes, des galaxies, des astéroïdes, des comètes, mais les trous noirs en sont certainement les habitants les plus mystérieux et les plus fascinants ! Grâce à cette merveilleuse histoire racontée par papy Gino, professeur d'astronomie, les trous noirs n auront plus de secrets pour vous ! C est l'été, le soleil illumine le ciel, la plage est en feu : une journée à la plage pleine de jeux et de plongée qui va se transformer pour Bernardo, Gregorio et leurs deux amis en une aventure inattendue. Ils découvriront les secrets des trous noirs, d étranges objets célestes que personne n'a jamais vus mais qui existent bel et bien ! Grand-père Gino, un professeur d astronomie à la retraite, emmènera les enfants à l'intérieur d'un trou noir, leur expliquera pourquoi ils sont noirs, comment ils sont nés et comment les scientifiques pensent qu'ils vont mourir. Et Gino leur racontera même ce qui se trouve de l'autre côté d'un trou noir...

  9. Les Cahiers du CREAD

    African Journals Online (AJOL)

    Admin

    phénomène et son évolution sur la période 1990-2009. A cet effet, ... que les dépenses publiques, le taux d'inflation, le taux de chômage et le SNMG sont les ..... economy into the dynamics of Post-Socialist economies: A framework of analysis ...

  10. Les Cahiers du CREAD

    African Journals Online (AJOL)

    Admin

    politiques, au cœur de cette stratégie développementiste qui a enfanté. 3 La formation ... humaines dans l'une des entreprises nationales algériennes pendant les ...... les années comme critères de recrutement pour deux différents niveaux ...

  11. Les Cahiers du CREAD

    African Journals Online (AJOL)

    Admin

    élimination. ... Les propriétés physiques et thermiques des différents types de déchets solides, tels ... des politiques en matière de gestion des déchets en Europe depuis les ..... soit un volume de stockage des déchets de plus de 1 520 440 m3.

  12. A study of filtering problems of background noise in nuclear spectrometry, improvement of signal-to-noise ratio, and of pulse characteristics produced by the optimum predictor device; Etude de problemes de filtrage de bruit de fond en spectrometrie nucleaire, amelioration du rapport signal sur bruit et des caracteristiques de l'impulsion mise en forme par le dispositif du predicteur optimum

    Energy Technology Data Exchange (ETDEWEB)

    Benda, J [Commissariat a l' Energie Atomique, 91 - Saclay (France). Centre d' Etudes Nucleaires

    1967-05-01

    The purpose of nuclear spectrometry is the precise measurement of particles energy. The resolving power of a spectrometer design is an important factor. Two main phenomena are involved in the limitation of this resolving power: The statistical fluctuations of the detector itself, and the background noise. For a given noise, the theory of filters enables the calculation of networks specially designed for the improvement of signal to noise ratio. The proposed system should lead to an improvement of 10.5 per cent of this ratio. Experiments have confirmed this theoretical estimation. The predictor device also makes possible the obtaining of shortened pulses. (author) [French] Les mesures en spectrometrie nucleaire ont pour but la determination precise de l'energie des particules. Le pouvoir de resolution d'une chaine de spectrometrie est une caracteristique importante. Deux phenomenes principaux concourent a limiter ce pouvoir de resolution: les fluctuations statistiques du detecteur et le bruit de fond. Pour un bruit de fond donne, la theorie des filtres permet de calculer des reseaux susceptibles de modifier le rapport signal sur bruit. Le systeme propose permet d'ameliorer de 10.5 pour cent ce rapport lorsqu'on se place dans les conditions optimales. Les resultats experimentaux confirment les previsions. Le dispositif predicteur permet aussi un raccourcissement de l'impulsion dans le temps. (auteur)

  13. Les souvenirs du fondateur

    Directory of Open Access Journals (Sweden)

    Marie-Thérèse Curie

    2009-11-01

    Full Text Available J’étais vicaire à Notre-Dame de Dole dans les années cinquante. Cette fonction, à cette époque, me mettait en contact permanent avec les mouvements de jeunesse, ceux de l’âge d’or des « patros » et des colonies de vacances. On me demanda d’ailleurs de créer plusieurs de ces « colos » de filles (La Rixouse, les Rivières, les Perrets dans le Jura, mais aussi à l’île d’Yeu pour le diocèse. Mon bon contact avec les jeunes et la confiance de ma hiérarchie me désignèrent pour m’occuper d’une paroi...

  14. Professional Nuclear Materials Management; Gestion Industrielle des Matieres Nucleaires; Obrashchenie s yadernymi materialami na professional'nom urovne; Administracion Eficiente de Materiales Nucleares

    Energy Technology Data Exchange (ETDEWEB)

    Forcella, A. A.; O' Leary, W. J. [Allis-Chalmers Manufacturing Company, Bethesda, MD (United States)

    1966-02-15

    . (author) [French] Le memoire expose en quoi consiste la gestion des matieres nucleaires dans une centrale nucleaire type, aux Etats-Unis. Comme le reacteur en question est partiellement finance a l'aide de capitaux prives, l'une des principales obligations de l'exploitant est d'assurer la protection et la rentabilite des investissements. Etant donne que les matieres nucleaires sont d'une valeur intrinseque elevee, il faut constamment proceder a des controles appropries allant au-dela des mesures de securite et de la comptabilite interessant les matieresnucleaires proprement dites afin de reduire les pertes au minimum. Il faut faire preuve de clairvoyance et planifier judicieusement pour prevenir toute perte supplementaire de capital provenant de frais inutiles ou d'un manque a gagner dans divers secteurs de l'exploitation. C'est ainsi que le gestionnaire de matieres nucleaires doit prendre des dispositions pour garantir la bonne marche des operations et assurer le respect des plans d'execution par une liaison et un controle constants, dans les domaines suivants? a) acquisition du combustible et des elements combustibles, b) utilisation des elements combustibles dans le reacteur et c) recuperation, dans le combustible irradie, des produits et matieres presentant de l'interet. Pendant la periode qui precede l'utilisation du reacteur, il faut faire une place importante dans la planification et les travaux preparatoires aux considerations d'economie dans la conception des elements combustibles, en ce qui concerne leur fabrication, leur manutention, leur transport et leur remplacement. Les differentes etapes de la fabrication doivent etre planifiees de facon a reduire au minimum le manque a gagner du a des periodes improductives d'entreposage de matieres tres couteuses. Pendant la marche du reacteur, il faut assurer une combustion maximale de la matiere fissile par des redistributions appropriees du combustible dans le coeur du reacteur. Parallelement, les temps morts dus a

  15. Experimental validation of calculation schemes connected with PWR absorbers and burnable poisons; Validation experimentale des schemas de calcul relatifs aux absorbants et poisons consommables dans les REP

    Energy Technology Data Exchange (ETDEWEB)

    Klenov, P.

    1995-10-01

    In France 80% of electricity is produced by PWR reactors. For a better exploitation of these reactors a modular computer code Apollo-II has been developed. his code compute the flux transport by discrete ordinate method or by probabilistic collisions on extended configurations such as reactor cells, assemblies or little cores. For validation of this code on mixed oxide fuel lattices with absorbers an experimental program Epicure in the reactor Eole was induced. This thesis is devoted to the validation of the Apollo code according to the results of the Epicure program. 43 refs., 65 figs., 1 append.

  16. Numerical and Experimental Study on the Combustion and Emission Characteristics of a Dimethyl Ether (DME Fueled Compression Ignition Engine Études numériques et expérimentales sur les caractéristiques de combustion et d’émissions d’un éther diméthylique (EDM- moteur à auto-allumage rempli de combustible

    Directory of Open Access Journals (Sweden)

    Kim Hyung Jun

    2012-05-01

    Full Text Available A numerical investigation was carried out to study on the combustion and emission characteristics of dimethyl ether (DME with wide ranges of injection timings in compression ignition engines. In order to simulate DME combustion processes, a KIVA-3V code coupled with a chemistry solver was used to solve the detailed chemical kinetics model of DME oxidation. In addition, the Kelvin-Helmholtz-Rayleigh-Taylor (KH-RT hybrid breakup model and Renormalization Group (RNG k-ε  models were applied to analyze the spray characteristics and turbulent flow, respectively. To predict the NOx formation during DME combustion, a reduced Gas Research Institute (GRI NO mechanism was used. From these results on the combustion and emission, the calculated results were compared with experimental ones for the same operating conditions. In the combustion characteristics, the calculated combustion pressure and heat release rates agreed well with experimental results. The levels of experimental NOx emissions was reduced as the start of the injection timing retarded, and also these trends appeared in calculated emission characteristics. Additionally, the calculated CO and HC emissions show an increasing trend as the start of the injection is retarded. Dans cette étude, nous considérons la simulation de la combustion du dimethyl ether (DME dans un moteur à allumage par compression. Les caractéristiques de la combustion ainsi que les émissions polluantes sont analysées sur une large gamme d’avance à l’injection. Afin de simuler le processus de combustion du EDM, le code KIVA-3V couplé à un solveur chimique a été utilisé pour résoudre la cinétique détaillée de l’oxydation du EDM. Le modèle de rupture de Kelvin-Helmholtz-Rayleigh- Taylor (KH-RT ainsi que le modèle de turbulence k-ε  RNG ont été appliqués pour analyser respectivement les caractéristiques du jet et l’écoulement turbulent. Pour prévoir la formation de NOx pendant la combustion

  17. Nuclear program of Iran. Towards de-escalation of a nuclear crisis. Advisory letter; Nucleair programma van Iran. Naar de-escalatie van een nucleaire crisis. Briefadvies

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2012-04-15

    The Dutch government, partly at the request of the House of Representatives (Second Chamber), the AIV asked to give an opinion about the position of Iran in the region and the role of the nuclear program of Iran in the geopolitical relations, in view of the most recent developments [Dutch] De Nederlandse regering heeft, mede op verzoek van de Tweede Kamer der Staten-Generaal, de AIV gevraagd advies uit te brengen over de positie van Iran in de regio en de rol van het nucleaire programma van Iran in de geopolitieke verhoudingen hierin, mede gelet op de meest recente ontwikkelingen.

  18. A study of the fluorescence of the rare gases excited by nuclear particles. Use of the principle for the detection of nuclear radiation by scintillation; Etude de la fluorescence des gaz rares excites par des particules nucleaires. Utilisation pour la detection des rayonnements nucleaires par scintillation

    Energy Technology Data Exchange (ETDEWEB)

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

    1959-12-15

    composantes, l'une tres breve due a la desexcitation directe du gaz rare, l'autre relativement plus lente, due au transfert d'energie sur les impuretes. La mesure des durees de vie des etats excites a confirme l'hypothese precedente, la partie breve de l'impulsion est extremement courte: inferieure a 2,25.10{sup -9} s dans le cas du xenon, la partie plus lente a une duree qui depend etroitement de la concentration d'azote, l'azote etant l'impurete dont le role est preponderant dans tous les cas. L'etude des gaz rares soumis a un champ electrique a permis de montrer que la quantite de lumiere produite par une particule {alpha} peut etre multipliee (par 60 dans un champ de 600 V/cm par exemple) ce qui correspond a un rendement de luminescence superieur a celui de INa TI. Dans la deuxieme partie on a etudie les caracteristiques des gaz rares comme scintillateurs, la plus importante est l'absence de saturation de la fluorescence lorsque la densite d'excitation transmise au gaz devient tres grande. Ceci joint au temps de scintillation tres court a permis d'etudier un certain nombre d'applications a la physique nucleaire (mesure d'energie des particules lourdes, etude cinetique des reacteurs nucleaires, spectroscopie des neutrons...). (auteur)

  19. Development of mercury porosimeter. Application to nuclear graphite studies (1961); Mise au point d'un porosimetre a mercure. Application a l'etude des graphites nucleaires (1961)

    Energy Technology Data Exchange (ETDEWEB)

    Bocquet, M; Genisson, J; Sailleau, J [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1961-07-01

    A mercury porosimeter, model IFP-CEA, has been developed for application to nuclear graphite studies. The apparatus is based on the capillary depression phenomenon. The relationship between the radius of a pore and the pressure at which mercury fills it is pr = -2 {sigma} cos {theta} ( {sigma} is the surface tension, {theta} the angle of contact of the mercury). After some theoretical consideration, the apparatus is described. The mercury pressure is increased step-wise from 0 to 1000 kg/cm{sup 2} thus yielding the complete distribution of pores from 92 {mu} to 75 A. Results are, then presented concerning nuclear graphites which show the evolution of the porous structure under the effect of bitumen impregnation. In general, the volume of the large pores decreases while that of the small pores increases. The structure of impregnated products appears to depend to a certain extent on that of the starting materials. It has also been possible to study other products with this porosimeter; the range of measurements possible is such that it may be used for the study of the majority of porous materials. (authors) [French] Un porosimetre a mercure modele IFP-CEA a ete mis au point en vue de son application a l'etude de graphites nucleaires. Le fonctionnement de l'appareil repose sur le phenomene de depression capillaire. On etablit la relation existant entre le rayon r d'un pore et la pression p pour laquelle le mercure peut y penetrer: pr = -2 {sigma} cos {theta} ( {sigma} tension superficielle, {theta} angle de contact du mercure). Apres quelques considerations theoriques, l'appareil utilise est decrit. Il permet de faire varier par palier la pression du mercure entre 0 et 1000 kg/cm{sup 2} et d'etablir ainsi la distribution complete des rayons de pores compris entre 92 {mu} et 75 A. Les resultats d'une etude faite sur des graphites nucleaires sont alors presentes faisant apparaitre l'evolution de la structure poreuse sous l'effet des impregnations au brai. D'une facon

  20. Les poissons de Guyane

    OpenAIRE

    Ifremer

    1992-01-01

    Vous trouverez dans ce document les 24 poissons les plus courants de Guyane (sur un nombre d'espèces approchant les 200) avec leurs principales caractéristiques, leurs noms scientifiques, français, anglais et espagnol et leurs photographies. Ils sont classés, de l'acoupa au vivaneau ti yeux, par ordre alphabétique. Si vous ne trouvez pas de chiffres sur la production de telle ou telle espèce, c'est parce qu'ils n'existent pas, mais aussi et surtout parce qu'ils ne signifieraient rien, l...

  1. Mesurer et comparer les contextes et les politiques alimentaires en ...

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

    En Amérique latine, les maladies non transmissibles (MNT) sont responsables de trois décès sur quatre. Une mauvaise alimentation fait augmenter de plus en plus les décès et les maladies évitables et prématurées liés aux MNT. Dans le but de régler ce problème, ce projet suivra et comparera les contextes et les ...

  2. Heat exchange and pressure drop of herring-bone fin surfaces. Experimental cell results at constant wall temperature; Echange de chaleur et perte de charge de surfaces a ailettes en chevrons. Resultats experimentaux en cellule a temperature de paroi constante

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1968-07-01

    The increase in the specific power of nuclear reactors of the gas-graphite type has necessitated the use of high performance exchange surfaces for canning the fuel (natural uranium). For this, experiments were carried out on cans fitted with herring-bone fins, at constant wall temperature; a flow of water at 100 deg. C passes inside the can which is cooled externally by a flow of CO{sub 2} at 15 bars pressure. This experimental set-up makes it possible to compare the aero-thermal performances of the different cans with an accuracy of 5 per cent. This report presents the results obtained in the form of a friction coefficient f{sub 0} and mean Margoulis number m{sub 0} as a function of the Reynolds number Re{sub 0}, this latter varying from 3 x 10{sup 5} to 9 x 10{sup 5}. (authors) [French] L'augmentation de la puissance specifique des reacteurs nucleaires de la filiere graphite-gaz a necessite l'utilisation de surfaces d'echange a hautes performances pour gainer le combustible (uranium naturel). Dans cette optique, des gaines munies d'ailettes disposees en chevron ont ete experimentees a temperature de paroi constante: un courant d'eau a 100 deg. C circule a l'interieur de la gaine qui est refroidie exterieurement par un ecoulement de CO{sub 2} sous une pression de 15 bars. Cette methode experimentale permet de situer les performances aerothermiques des gaines les unes par rapport aux autres a 5 pour cent pres. Ce rapport presente les resultats obtenus sous la forme d'un coefficient de frottement f{sub 0} et d'un nombre de Margoulis moyen m{sub 0} en fonction du nombre de Reynolds Re{sub 0}, ce dernier pouvant varier de 3. 10{sup 5} a 9. 10{sup 5}. (auteurs)

  3. Behaviour of semiconductor nuclear-particle detectors; Comportement des semi-conducteurs comme detecteurs de particules nucleaires; Povedenie detektorov yadernykh chastits na poluprovodnikakh; Propiedades de los detectores de particulas nucleares a base de semiconductores

    Energy Technology Data Exchange (ETDEWEB)

    Walter, F J; Dabbs, J W.T.; Roberts, L D [Oak Ridge National Laboratory, Oak Ridge, TN (United States)

    1962-04-15

    . Matched expansion-coefficient fabrication techniques which have been successfully used to make detectors up to 8 cm{sup 2} in active area are also described. (author) [French] Les auteurs ont fait des etudes theoriques et experimentales sur le comportement des semi-conducteurs comme detecteurs de particules nucleaires a des temperatures allant de 0,2{sup o} K a 300{sup o} K. Ils presentent un modele theorique simple du comportement du detecteur qui correspond au comportement observe pour toute une gamme de valeurs des parametres. Ils examinent quelle est l'importance de la purete du semi-conducteur et de la tension de polarisation en ce qui concerne l'amplitude de l'impulsion, le temps de montee de l'impulsion et la surface du detecteur. Des etudes empiriques sur le bruit et la resolution en energie montrent que, pour des particules alpha, les plus petites largeurs de crete observees sont tres nettement plus importantes que les largeurs que l'on avait prevues en tenant compte du bruit d'origine electrique provenant du detecteur et de l'amplificateur. A 77{sup o}K, on a releve pour un detecteur a barriere de surface au silicium, d'une surface de 40 mm{sup 2}, des intensites de bruit equivalant a {<=} 3 keV (largeur totale a mi-hauteur du maximum). Les semi-conducteurs presentent un a l'egard des fragments de fission. On a tout lieu de penser que ce defaut n'est pas du a une . Si des champs electriques insuffisants pour assurer une complete sont la cause de ce defaut, le gradient de champ necessaire (a la surface) est superieur a 3 {center_dot} 10{sup 4} V/cm dans le cas de fragments de fission contre 2 {center_dot} 10{sup 3} V/cm dans le cas de particules alpha de Ge et de Si. Des etudes detaillees sur le temps de montee des impulsions au niveau de l'amplificateur ont montre que pour des substances de grande resistivite le temps de relaxation dielectrique et la resistance propres aux substances de base non appauvries peuvent

  4. Les chemins du savoir

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

    Cathy Egan

    solutions africaines aux problèmes causés par les politiques d'ajustement structurel sévères imposées par les institutions financières internationales. Aujourd'hui, cet organisme à but non lucratif, se place au premier rang des organismes de recherche en économie en. « Quand la démocratie bat de l'aile dans un pays, tout.

  5. LES PAYS EN TRANSITION

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

    Cathy Egan

    En 2002, une certaine paix sociale avait été rétablie, bien qu'elle fut instable et souvent entachée de violence. Le pays amorçait le ... mieux comprendre comment il recueille et diffuse l'information destinée ... transition) et les technologies de l'information et de la communication (TIC). Les étapes suivantes ont consisté à ...

  6. Separation of Graphitic Line in Debyegram of the Reactor Graphite; Separation de la raie graphitique dans le debyegramme du graphite nucleaire; Otdelenie linii grafita v debaiegramme reaktornogo grafita; Separacion de la linea grafitica en el diagrama de debye del grafito nuclear

    Energy Technology Data Exchange (ETDEWEB)

    Pandic, B. [Institut Rudjer Boskovio, Zagreb, Yugoslavia (Croatia)

    1963-11-15

    The author sets forth a method for the determination of crystallite dimensions L{sub c} in reactor graphite. The method consists of the mathematical correction of the diffraction profile (002) obtained by means of a Philips diffractometer with scintillation counter. During the work CuK{sub {beta}} radiation is used. The convenience of using CuK{sub {beta}} radiation rather than that of a CuK{sub {alpha}} doublet is discussed. All instrumental errors except that of the sample adsorption are eliminated using corresponding slits. Sample adsorption is corrected mathematically. Highly symmetrical lines of graphitic and non-graphitic phase could be analytically separated from such corrected line profiles. Experimental error in the determination of the half-height and half-width of these lines does not exceed 5%. (author) [French] On a elabore une methode pour determiner la hauteur moyenne L{sub c} des cristallites du graphite nucleaire. Il s'agit d'une methode mathematique de correction du profil de la raie de diffraction (002), obtenu par le diffractometre Philips avec un compteur a scintillation. On a discute les avantages des rayons CuK{sub {beta}} par rapport au doublet CuK{sub {alpha}}. Le choix des ouvertures elimine toutes les erreurs, sauf l'erreur d'absorption dans les echantillons, que l 'on ecarte mathematiquement. Les raies de diffraction pures et tres symetriques des phases graphitique et non graphitique peuvent etre separees du profil corrige de cette facon. L'incertitude dans la mesure de la demi-largeur de ces raies n'est pas superieure a 5%. (author) [Spanish] El autor de la memoria expone un metodo para determinar la altura media Lc de las cristalitas del grafito nuclear. Consiste en corregir matematicamente el perfil de la linea de difraccion (002) obtenido con un difractometro Philips y un contador de centelleo. En la memoria se explican las ventajas que la radiacion CuK{sub {beta}} ofrece sobre el doblete CuK{sub {alpha}} Si se elige correctamente la

  7. Lesles sexospécifiques et la violence dans les villes | CRDI ...

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

    20 oct. 2017 ... Une croissance rapide et des identités sexuelles ancrées favorisent la violence ... services des villes mettent les femmes et les minorités sexuelles en danger. .... Une étude de cas sur les femmes et les transports à Guwahati ...

  8. Abolir les obstacles que constituent les frais de santé : les ...

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

    10 juin 2016 ... Abolir les obstacles que constituent les frais de santé : les ... Le financement des services de santé repose sur un système de ... Dans les années 1980, conformément aux recommandations d'organismes internationaux, ...

  9. Information manual for the experimentation of the deployment of optical fibers on public power distribution networks; Notice d'information pour l'experimentation du deploiement de fibres optiques sur les reseaux publics d'electricite

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-07-01

    During the French inter-ministry committee for the national development (CIADT) of July 9, 2001, the government decided to launch a feasibility study about the deployment of telecommunication optical fibers over the whole territory using the electricity transportation grid. The aim is to give access to high-speed Internet to everyone and at a reasonable cost. This manual summarizes the technical, legal and economical results of the study carried out by the working group: 1 - the actors in concern (managers of power transportation and distribution networks, country authorities, managers and users of telecommunication infrastructures, regulatory agencies, financial organizations); 2 - the telecommunication networks on power lines; 3 - the feasibility of the experimentation (relations between the different partners, conditions); 4 - the implementation of the experimentation (useful contacts, contracts); 5 - the experimentation areas. Appendixes. (J.S.)

  10. Information manual for the experimentation of the deployment of optical fibers on public power distribution networks; Notice d'information pour l'experimentation du deploiement de fibres optiques sur les reseaux publics d'electricite

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-07-01

    During the French inter-ministry committee for the national development (CIADT) of July 9, 2001, the government decided to launch a feasibility study about the deployment of telecommunication optical fibers over the whole territory using the electricity transportation grid. The aim is to give access to high-speed Internet to everyone and at a reasonable cost. This manual summarizes the technical, legal and economical results of the study carried out by the working group: 1 - the actors in concern (managers of power transportation and distribution networks, country authorities, managers and users of telecommunication infrastructures, regulatory agencies, financial organizations); 2 - the telecommunication networks on power lines; 3 - the feasibility of the experimentation (relations between the different partners, conditions); 4 - the implementation of the experimentation (useful contacts, contracts); 5 - the experimentation areas. Appendixes. (J.S.)

  11. Double protection passive pour les equipages de l'helicoptere d'attaque "Tigre" : Concept et etude experimentale (Design and Experimental Study of the Passive Double Hearing Protection for the Crew of the Attack Helicopter "Tiger")

    National Research Council Canada - National Science Library

    Baudou, J; Reynaud, G; Poussin, G; Leger, A

    2005-01-01

    .... Par sa simplicite de mise en oeuvre, sans impact sur le casque, son faible cout et son efficacite d'attenuation propre, la protection complementaire offerte par les bouchons d'oreille passifs s'est...

  12. Inhibition of the radiolytic hydrogen production in the nuclear waste of 'bitumen coated' type: study of the interaction between hydrogen and cobalt hydroxo-sulphide; Inhibition de la production d'hydrogene radiolytique dans les dechets nucleaires de type 'enrobes bitumineux': etude de l'interaction entre l'hydrogene et l'hydroxosulfure de cobalt

    Energy Technology Data Exchange (ETDEWEB)

    Pichon, C

    2006-11-15

    sulphide in gaseous phase and the Co(OH){sub 2} phase disappearance, could be explained according to the reaction (2): 9 Co(OH){sub 2} + 8 H{sub 2}S + H{sub 2} = Co{sub 9}S{sub 8} + 18 H{sub 2}O (2). By taking account of (1) and (2), the theoretical ratio of the quantity of hydrogen fixed per mole of cobalt is 0.56, which is in agreement with the experimental value (0.59). The analysis of the kinetic curves deduced from the gravimetry experiments were qualitatively analysed in terms of nucleation and growth processes in order to explain the phenomenon of 'trapping' at various temperatures. (auth0008.

  13. Lesões perinatais em bovinos na intoxicação experimental por Ateleia glazioviana (Leg.Papilionoideae Perinatal lesions in cattle experimentally poisoned by Ateleia glazioviana (Leg. Papilionoideae

    Directory of Open Access Journals (Sweden)

    Maria del Carmen García y Santos

    2004-12-01

    Full Text Available Folhas de Ateleia glazioviana Baill., dessecadas em estufa a 100ºC por 16 a 20 horas, foram administradas a sete vacas sem raça definida. Duas vacas receberam 9 g/kg da planta seca aos 4 meses de gestação em dose única. Três vacas no 8º mês de gestação, receberam doses diárias de 1 a 2 g/kg da planta seca, perfazendo totais de 10, 21 e 28 g/kg. Duas outras, também no 8º mês de gestação, receberam a planta seca em dose única 15,5 e 18 g/kg. Duas vacas, no 4º mês de gestação, receberam 35 g/kg da planta verde, em dose única. A vaca que recebeu 21 g/kg da planta seca foi a única a apresentar sinais clínicos de intoxicação e o bezerro nasceu morto. As demais vacas não apresentaram sinais clínicos. Os bezerros das vacas que receberam a planta seca nas doses de 9, 15,5 e 28 g/kg, apresentaram sinais clínicos de debilidade, dificuldade de manter-se em pé e mamar e foram sacrificados. Macroscopicamente, no bezerro que nasceu morto, foram observados áreas esbranquiçadas e espessamento da parede do ventrículo cardíaco direito. Os demais bezerros que nasceram fracos foram sacrificados e não apresentaram lesões macroscópicas, com exceção do bezerro da vaca que recebeu a planta seca, na dose total de 28g/kg, que apresentou, também, espessamento da parede do ventrículo direito. As alterações histológicas do bezerro que nasceu morto e dos que foram sacrificados por apresentarem sinais clínicos de debilidade caracterizaram-se por tumefação e vacuolização de feixes de fibras musculares e proliferação de tecido fibroso entre os cardiomiócitos. Essas lesões são semelhantes às observadas em casos espontâneos da intoxicação. Os cardiomiócitos mostraram reação PAS positiva no sarcoplasma, mais acentuada do que no animal controle. No bezerro que nasceu morto foi observado, também, espongiose discreta na substância branca do cerebelo, colículos rostrais e tálamo. O estudo ultra-estrutural do cora

  14. Experimental study of flux depressions and anti-reactivities created by irradiation loops; Etude experimentale des depressions de flux et antireactivites creees par les dispositifs d'irradiation

    Energy Technology Data Exchange (ETDEWEB)

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

    1967-07-01

    Methods for fast computing of thermal flux depressions and reactivities created by irradiation-loops in natural water reactors are studied in this report. The classical methods of approximation which have been used are: diffusion theory or absorption-probability calculations for the flux-depression and perturbation theory for the anti-reactivities. Pertinent formulae are compiled together with graphs from theoretical calculations. These formulae and graphs have been checked from numerous experiments which show that the approximations used here are quite close to the actual physical situation, even when the theories are based from assumptions which cannot be verified here. (author) [French] Ce rapport propose aux experimentateurs des piles a eau legere des methodes de determination rapide des depressions de flux thermique et antireactivites creees par les dispositifs d'irradiation. Les methodes classiques d'approximation sont utilisees, a savoir: theorie de diffusion ou calcul de probabilites d'absorption pour les depressions de flux, theorie des perturbations pour les antireactivites. Un formulaire pratique, accompagne d'abaques est deduit des calculs theoriques et verifie par de nombreuses experiences qui montrent que les evaluations faites sont tres proches de la realite, meme dans le cas ou les hypotheses relatives aux theories utilisees ne sont pas respectees. (auteur)

  15. Nuclear systems of the future - generation 4. Proposals of strategic orientations for the nuclear systems of the future; Les systemes nucleaires du futur - generation 4. Propositions d'orientations strategiques pour les systemes nucleaires du futur

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2007-07-01

    Several points, specific to France, must be taken into consideration for the long term strategic choice of future nuclear systems, in particular: taking the best profit of the progress potentialities of water reactors, optimizing the opportunities offered by the renewal of power plants in operation, integrating the consequences and the implementation of a strategy of optimized management of radioactive wastes, and looking for improvements that would make nuclear energy an active contributor to sustainable development. The prospective researches carried out by the CEA and its industrial partners have led to propose a R and D strategy with 3 complementary goals: search for innovations for water reactors, development of fast neutron reactors with closed fuel cycle (sodium fast reactor (SFR), gas fast reactor (GFR)), and development of key-technologies for nuclear hydrogen production (very high temperature reactor (VHTR)). The R and D effort concerns also the subcritical systems devoted to transmutation, the new cycle processes for a global management of actinides, and some other nuclear systems like the molten salt reactors (MSR) and the supercritical water reactors (SCWR). This paper presents the R and D strategy for each technology with its priorities, steps, financial means and collaborations. (J.S.)

  16. Efeito da utilização de um centrifugado de medula óssea no tratamento de lesão muscular: estudo experimental em coelhos Effect of use of bone-marrow centrifugate on muscle injury treatment: experimental study on rabbits

    Directory of Open Access Journals (Sweden)

    Daniel Ferreira Fernandes Vieira

    2011-01-01

    Full Text Available OBJETIVO: O objetivo deste estudo foi de avaliar o efeito de um centrifugado de medula óssea na cicatrização de lesão muscular em coelhos. MÉTODOS: Este estudo experimental envolveu a utilização de 15 coelhos machos, adultos, da raça Nova Zelândia Branco. Em cada animal, realizou-se uma lesão transversal na região média do músculo tibial anterior direito, onde se adicionou uma esponja de colágeno absorvível, embebida em um centrifugado de aspirado de medula óssea do osso ilíaco ipsilateral. O membro posterior esquerdo foi utilizado como controle, sendo submetido à mesma lesão; porém, neste caso, adicionando-se somente a esponja de colágeno absorvível. Após 30 dias, os animais foram sacrificados para o estudo da cicatrização muscular. As áreas de cicatrização muscular foram submetidas à análise histológica com histomorfometria, interessando-se a mensuração do número de células musculares em regeneração por micrômetro quadrado e a proporção de fibrose formada. RESULTADOS: O método de centrifugação utilizado neste estudo resultou em uma concentração média de células nucleadas maior que o número destas células nos aspirados originais, sem provocar destruição celular significativa. A adição do centrifugado de medula óssea não resultou em aumento significante do número de células musculares em regeneração em relação ao grupo controle. Também não houve diferença significante na proporção de fibrose formada em relação ao grupo controle. CONCLUSÃO: A administração de centrifugado de medula óssea utilizada neste estudo não favoreceu a cicatrização de lesão muscular em coelhos.OBJECTIVE: The objective of this study was to evaluate the effect of bone-marrow centrifugate on the healing of muscle injuries in rabbits. METHODS: This experimental study involved use of fifteen adult male New Zealand White rabbits. Each animal received a transverse lesion in the middle of the right

  17. Artaud et les Tarahumaras

    Directory of Open Access Journals (Sweden)

    Marta Mariasole Raimondi

    2008-01-01

    Full Text Available Ce film propose des scènes de vie des Tarahumaras, une ethnie originaire du Mexique installée dans le territoire de l'Etat de Chiuahua, dans un milieu montagneux très sauvage. La caméra reprend les danses et les rites de ces mangeurs de peyotl d'un regard rapide et saccadé primant des cadrages de détail où prédominent les pieds, pour nous montrer ces corps d'homme et de femme en mouvement, courant, dansant, bondissant au milieu des leurs éléments naturels : rocailles, rivières, rochers, sans...

  18. Prospects for the Use of Plutonium in Reactors; Prospective d'Utilisation du Plutonium dans les Reacteurs

    Energy Technology Data Exchange (ETDEWEB)

    Fossoul, E.; Haubert, P. [BELGONUCLEAIRE (Belgium); Hirschberg, D.; Morlet, E. [International Business Machines of Belgium, Bruxelles (Belgium)

    1967-09-15

    The introduction, at an increasing rate, of power reactors using slightly enriched uranium will inevitably lead to the production of considerable quantities of plutonium over the next decade. Fast reactors will not be capable of absorbing this material before 1980. The question thus arises of whether one should store the plutonium far future use in fast reactors, recycle it in existing thermal reactors, or try to sell it. The problem has been studied for an electric power generating system that does not foresee selling the plutonium produced by its reactors and does not buy plutonium outside, which enables a good approximation to be made and eliminates the major unknown quantity represented by the future market price of plutonium. Assuming within this system a programme that provides for the construction of power reactors of a given type and capacity at specific dates, the utilization of the plutonium produced can be optimized by linear programming techniques so as to minimize the discounted total cost of the power generated over a given period. A later stage consists in optimizing, by various techniques, not only the utilization but also the production of plutonium by appropriate selection of the power reactor types to be constructed. (author) [French] L'implantation, a un rythme croissant, de centrales nucleaires a uranium legerement enrichi entrainera la production ineluctable d'une quantite importante de plutonium au cours de la prochaine decennie. Les reacteurs a neutrons rapides ne seront capables d'absorber cette production qu'apres 1980. La question se pose donc de savoir s'il est preferable de stocker le plutonium en vue de son utilisation ulterieure dans les reacteurs a neutrons rapides plutot que de le recycler dans les reacteurs actuels a neutrons thermiques ou d'essayer de le vendre. Ce probleme a ete etudie dans le cadre d'un systeme de production d'energie electrique qui ne prevoirait pas la vente du plutonium produit par ses reacteurs nucleaires ni

  19. Nuclear Energy, a way for tomorrow spacecrafts; L'energie nucleaire, une voie pour les vaisseaux spatiaux de demain

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2002-07-01

    To better explore the solar system, the NASA will uses new propulsion modes, in particular the nuclear energy. These articles present the research programs in the domain and the particularities of the nuclear energy in the projects. (A.L.B.)

  20. How will fourth-generation nuclear systems be deployed?; Comment les systemes nucleaires de 4. generation se deploieront-ils?

    Energy Technology Data Exchange (ETDEWEB)

    Bonin, B.; Carre, F. [CEA Saclay, Dir. de l' Energie Nucleaire, 91 - Gif sur Yvette (France)

    2007-07-01

    If it is to be fully consonant with a sustainable development perspective, nuclear energy needs must rely on systems that will ensure the greatest optimization of fissile material utilization, while minimizing production of ultimate waste. Deployment scenarios, for systems of the new generation, remain very much open. (authors)

  1. Radioactive waste and its impact on the environment; Les dechets nucleaires: quel impact sur l'environnement?

    Energy Technology Data Exchange (ETDEWEB)

    Bonin, B. [Institut de Radioprotection et de Surete Nucleaire en Detachement a Cogema, Dir. de la Recherche et du Developpement, 78 - Velizy (France)

    2002-07-01

    What impact will radioactive waste have on the environment and mankind ultimately? If category B waste and all or some of category C waste is disposed of in a deep geological facility, after an interim storage period which presents its own risks, scientists can now predict that its worst case impact will be minimal and localized. While they cannot strictly demonstrate the safety of disposal over the time scales in question, they can nevertheless vouch for sound, well-engineered design. They can furnish a whole host of convergent evidence to demonstrate that they really have thought of all the events that could affect radioactive packages disposed of in a given environment, separated from the biosphere by barriers with well-defined properties. (author)

  2. Health survey on cancers about the Tricastin nuclear site; Etude sanitaire sur les cancers autour du site nucleaire du Tricastin

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2010-07-01

    This survey aims at describing the health status of the population around the Tricastin site, and more particularly at determining whether there is a difference between death or cancer occurrence frequencies observed around this site with respect to reference frequencies. It does not aim at assessing the health impact of the site industrial installations. Cancer mortality data, cancer diagnosis data, demographic data, child cancer data, data related to hospital stays in relationship with cancer, long duration hospital stay data, and mortality data are used. Several indicators are defined and used: standardised mortality ratio, standardised hospitalisation ratio. Data are also analysed in terms of location, and socio-demographic categories. It appears that there is no specific health situation for the considered area, except for pancreas cancer for women

  3. Regional and international implications of the Iranian nuclear crisis; Les implications regionales et internationales de la crise nucleaire iranienne

    Energy Technology Data Exchange (ETDEWEB)

    Reveillard, Ch

    2006-07-15

    Iran is distinguished in the Middle East and the world by its geopolitical situation, qualified Middle Empire of the crossed worlds, which are all among the most active zones of the planet on the geopolitical and strategic plans. It undergoes on the one hand, region-al influences and inevitably in return acts in-depth on economic, strategic, diplomatic and cultural reality of its regional space made up of the three wholes: Central Asia, The Middle East, Persian Gulf open on the Indian Ocean. In addition, the singularity of its national policy, that tries to make move back the Anglo-Saxon impregnation of re-modelling the Middle East and the containment of the regional powers. (author)

  4. Y2K bug and nuclear installations; Le passage a l'an 2000 sur les installations nucleaires

    Energy Technology Data Exchange (ETDEWEB)

    Anon

    1999-10-01

    Most nuclear installations except power plants, will be shut down on the eve of new year. By september 1999, EDF will have realized all the corrective and preventive actions that are necessary to pass Y2K. CEA has committed to present to safety authorities a complete report concerning preventive actions in its own basic nuclear installations. Safety authorities plan to organize a crisis center in order to face any problem. (A.C.)

  5. The disappointments for nuclear energy in Japan; Les deconvenues pour l'energie nucleaire au Japon

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2004-07-01

    Several dysfunctions are reported in this paper: A reactor (Onagawa) closed after a nitrogen leakage; a small leakage of radioactive water in the nuclear power plant of Mihama assessment raised to five deaths, the operator stops its nuclear power plants for inspection, the Japan face to its ageing nuclear power plants, the truth about the cost of M.O.X., the seven reactors of Japan closed for inspection after cracks and leaks hidden to authorities, Tokai MURA accident. (N.C.)

  6. The Iran nuclear ambitions and the international consequences; Les ambitions nucleaires de l'Iran et leurs consequences internationales

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2005-01-15

    This analysis of the Iran situation concerning the nuclear policy, is presented and discussed in three parts: the data and hypothesis of the iranian nuclear program, the regional strategy of Iran and evolution scenario and their consequences. (A.L.B.)

  7. Dismantling of nuclear facilities: the industrial know-how; Demantelement des installations nucleaires: les voies de la maitrise industrielle

    Energy Technology Data Exchange (ETDEWEB)

    Lellament, R. [Societe Francaise d' Energie Nucleaire (SFEN), Groupe de Reflexion Energie/Environnement, 75 - Paris (France)

    2004-11-01

    Numerous nuclear facilities in laboratories or research reactors have been decommissioned and dismantled over the 2 last decades throughout the world. The valuable feedback experience has allowed nuclear industry to design, upgrade and test specific techniques for dismantling. These techniques are efficient although they have been validated on a reduced number of nuclear power plants. In France only 3 power units have been dismantled: Chinon A1, A2 and Brennilis (EL4) and they are not representative of the real park of EDF'reactors. 6 PWR-type reactors have already been dismantled in the Usa. The results of a survey concerning 26 countries shows that the dismantling cost is around 320 dollars/kWe, it represents 15% of the construction cost which is far from being excessive as it is often read in the media. The dismantling costs can be broken into: - de-construction (25-55%), - wastes from dismantling (17-43%), - security and monitoring (8-13%), - site reclamation (5-13%), and - engineering and project management (5-24%). (A.C.)

  8. Security report on Siloe - the descriptive part. (1963); Rapport de surete de Siloe - partie descriptive (1963)

    Energy Technology Data Exchange (ETDEWEB)

    Ageron, P; Chatoux, J; Denielou, G; Jacquemain, M; Mitault, G; Robien, E de; Rossillon, F [Commissariat a l' Energie Atomique, Grenoble (France). Centre d' Etudes Nucleaires

    1963-07-01

    This report is a full description of the site, the reactor, the building and the experimental facilities. It gives the nuclear, thermodynamic and hydrodynamic characteristics of the core. (authors) [French] Ce rapport decrit completement le site, le reacteur, les batiments et les installations experimentales. Il donne les caracteristiques nucleaires, thermodynamiques et hydrodynamiques du coeur. (auteurs)

  9. Experimental similitude determination of the influence of perturbations in the thickness of a heating channel on the isolated wall temperatures (1960); Determination experimentale en similitude de l'influence de perturbations dans l'epaisseur d'un canal chauffant sur les temperatures de la paroi isolee (1960)

    Energy Technology Data Exchange (ETDEWEB)

    Vernier, Ph [Commissariat a l' Energie Atomique, Grenoble (France).Centre d' Etudes Nucleaires; Commissariat a l' Energie Atomique, Saclay (France).Centre d' Etudes Nucleaires

    1960-07-01

    A study is made of the local heating phenomena produced on the isolated wall of a channel heated by the Joule effect by a sudden fluctuation in the conducting thickness. By the use of an experimental scale model it has been possible to measure the differences in the isolated wall temperature along the abscissa of the perturbation. The tests carried out show that the temperature differences are contained within a range of {+-} 4 per cent with respect to the temperature differences between the isolated and the isolated walls. (author) [French] On analyse le phenomene thermique local cree sur la paroi isolee d'un canal chauffe par effet Joule, par une perturbation brusque de l'epaisseur conductrice. Un modele experimental a l'echelle a permis de mesurer les ecarts de temperature de la paroi isolee a l'abscisse de la perturbation. Les essais realises ont montre que les ecarts de temperature se situaient dans une bande de {+-} 4 pour cent par rapport a l'ecart de temperature moyen entre paroi isolee et paroi refroidie. (auteur)

  10. Alteration of 'R7T7' type nuclear glasses: statistical approach, experimental validation, local evolution model; Alteration des verres nucleaires de type 'R7T7': demarche statistique, validation experimentale, modele local d'evolution

    Energy Technology Data Exchange (ETDEWEB)

    Thierry, F

    2003-02-01

    The aim of this work is to propose an evolution of nuclear (R7T7-type) glass alteration modeling. The first part of this thesis is about development and validation of the 'r(t)' model. This model which predicts the decrease of alteration rates in confined conditions is based upon a coupling between a first-order dissolution law and a diffusion barrier effect of the alteration gel layer. The values and the uncertainties regarding the main adjustable parameters of the model ({alpha}, Dg and C*) have been determined from a systematic study of the available experimental data. A program called INVERSION has been written for this purpose. This work lead to characterize the validity domain of the 'r(t)' model and to parametrize it. Validation experiments have been undertaken, confirming the validity of the parametrization over 200 days. A new model is proposed in the second part of this thesis. It is based on an inhibition of glass dissolution reaction by silicon coupled with a local description of silicon retention in the alteration gel layer. This model predicts the evolutions of boron and silicon concentrations in solution as well as the concentrations and retention profiles in the gel layer. These predictions have been compared to measurements of retention profiles by the secondary ion mass spectrometry (SIMS) method. The model has been validated on fractions of gel layer which reactivity present low or moderate disparities. (author)

  11. Experimental study of improvement of exchanged power in gases by catalytic dissociation: ammonia (1961); Etude experimentale de l'amelioration des echanges de chaleur avec les gaz par dissociation catalytique: ammoniac (1961)

    Energy Technology Data Exchange (ETDEWEB)

    Perroud, P [Commissariat a l' Energie Atomique, Grenoble (France). Centre d' Etudes Nucleaires; De La Harpe, A [Centre National de la Recherche Scientifique(CNRS), 75 - Paris (France)

    1961-07-01

    Rates of ammonia dissociation and resulting coefficients of improvement of exchanged power have been measured in an annular channel under following conditions: mean wall temperature until 1500 deg. C (tungsten rod, diameter 3 mm), mass velocity until 11 g/cm{sup 2}.s and absolute pressure between 1.5 and 7 kg/cm{sup 2}. Rate of dissociation is mainly function of wall temperature and total mass flow rate of ammonia; it depends little on entrance gas temperature and is practically independent of pressure. Apparent coefficients of improvement of exchanged power under above conditions (including radiation) have reached 1.8; this maximum was obtained for a mean wall temperature of 1250 deg. C. These coefficients decrease when Reynolds number increases. Finally, a theoretical analysis of the phenomenon is given as well as possibilities of application. (authors) [French] Les taux de dissociation d'ammoniac et les coefficients d'amelioration de puissance echangee resultants ont ete mesures en espace annulaire dans les conditions suivantes: temperature moyenne de paroi jusqu'a 1500 deg. C (barreau de tungstene de diametre 3 mm), vitesse massique jusqu'a 11 g/cm{sup 2}.s et pression absolue comprise entre 1,5 et 7 kg/cm{sup 2}. Le taux de dissociation est surtout fonction de la temperature de paroi et du debit en masse total d'ammoniac; il depend peu de la temperature d'entree du gaz et est pratiquement independant de la pression. Les coefficients d'amelioration apparents de la puissance echangee dans les conditions d'experience (rayonnement compris) ont atteint 1,8. Ce maximum observe se place vers une temperature moyenne de la paroi de 1250 deg. C. Ces coefficients decroissent quand le nombre de Reynolds de l'ecoulement croit. Finalement, une analyse theorique du phenomene est donnee ainsi que les perspectives d'applications. (auteurs)

  12. Contribution to the study of deformed heavy nuclei by means of nuclear reactions; Contribution a l'etude des noyaux lourds deformes au moyen de reactions nucleaires

    Energy Technology Data Exchange (ETDEWEB)

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

    1968-06-01

    The experimental results obtained in the study of the (d,p) reactions, at E{sub d} = 12 MeV, on the three even-even deformed nuclei {sup 170}Yb, {sup 172}Yb and {sup 174}Yb have been analysed in terms of DWBA calculations. The spectroscopic information relative to the odd final nuclei have been compared with the predictions of the collective model and of the Nilsson's model. The effect of various parameters used in the DWBA analysis (form factors, optical wave functions) has been carefully studied. The observed differences between the three final nuclei are qualitatively reproduced in the experimental study of resonances, seen in excitation functions of elastically and inelastically scattered protons on the same target nuclei, and corresponding to analogue states in the three nuclei {sup 171}Lu, {sup 173}Lu and {sup 175}Lu. (author) [French] Les resultats experimentaux de l'etude des reactions (d.p) a E{sub d} = 12 MeV, sur les noyaux deformes pairs-pairs {sup 170}Yb, {sup 172}Yb et {sup 174}Yb ont ete interpretes dans le cadre de l'approximation de Born des ondes deformees. Les informations spectroscopiques relatives aux noyaux impairs finals ont ete comparees aux predictions du modele collectif et du modele de Nilsson, apres avoir examine avec soin l'influence des differents parametres (facteurs de forme, fonctions d'onde 'optiques') utilises lors de l'analyse. Les differences observees entre les trois noyaux finals sont qualitativement reproduites par les resultats experimentaux de l'etude de resonances dans les fonctions d'excitation de diffusion elastique et inelastique de protons sur les memes noyaux-cibles, lors de la recherche d'etats analogues dans les noyaux {sup 171}Lu, {sup 173}Lu et {sup 175}Lu. (auteur)

  13. The Management of Nuclear Materials in a Research Establishment; Gestion des Matieres Nucleaires dans un Centre de Recherche; Uchet yadernykh materialov v nauchno-issledovatel'skom uchrezhdenii; Administracion de Sustancias Nucleares en un Centro de Investigaciones

    Energy Technology Data Exchange (ETDEWEB)

    Wright, W. J.; Hocking, D. R. [Australian Atomic Energy Commission Research Establishment, Lucas Heights, NSW (Australia)

    1966-02-15

    The functions of a nuclear materials management scheme are reviewed in relation to the activities of research establishments. Since these activities are normally non-repetitive, there is little opportunity to establish statistical quality and quantity control. The risks of an error in the material accounts must therefore be established from relatively few analytical measurements and the implications of this are discussed. Similar arguments are applied to illustrate the difficulties of quality control on suppliers when a large variety of materials are being purchased in small quantities. (author) [French] Les auteurs examinent le role d'un systeme de gestion des matieres nucleaires applique aux activites des centres de recherche. Comme ces activites ne sont normalement pas appelees a se repeter, il n'est guere possible d'organiser un controle statistique quantitatif et qualitatif. Il faut donc determiner les possibilites d'erreurs dans la comptabilite matieres en s'appuyant sur un nombre relativement restreint de mesures analytiques et les auteurs examinent les conclusions a tirer de cette situation. Ils recourent a une argumentation analogue pour illustrer les difficultes inherentes au controle de la qualite des matieres livrees par les fournisseurs lorsqu'il doit porter sur une grande diversite de matieres en petites quantites. (author) [Spanish] Los autores examinan el funcionamiento de un sistema de administracion de materiales nucleares en relacion con las actividades de los centros de investigaciones. Como estas actividades son por lo comun muy diversas, hay pocas oportunidades de establecer un control estadistico de la calidad y la cantidad. Por ello es necesario determinar los riesgos de error en la contabilidad de los materiales partiendo de un numero relativamente reducido de mediciones analiticas; en la memoria se examinan las consecuencias de este hecho. Los autores aplican razonamientos analogos para poner de manifiesto las dificultades con que, en el

  14. Les Cahiers du CREAD

    African Journals Online (AJOL)

    Admin

    Les opérations de croissance externe ayant une portée stratégique sont celles qui s'inscrivent dans une .... localisées dans des lieux différents, la politique de rationalisation est souvent ..... (recrutement de personnel, achat d'une machine, etc.) ...

  15. LES PAYS EN TRANSITION

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

    Cathy Egan

    Cette définition englobe les transformations bien connues .... soutenus à tout le moins par un directeur régional, un directeur de programme au siège et le ... Innover, aussi bien sur le plan de la conception des programmes que sur celui.

  16. les cahiers du cread

    African Journals Online (AJOL)

    Our Journal “les cahiers du cread” is a quarterly economic review publishing original findings of empirical research and theoretical debates on fields pertaining to our mission coverage (Macro Economics, Industrial Economics and Firms, Human Development & Social Economics, Agriculture & Environment). Other websites ...

  17. Preparation and study of the properties of lead telluride and cadmium telluride diodes for use in nuclear spectrometry; Preparation et etude des proprietes de diodes au tellurure de plomb et au tellurure de cadmium en vue d'une utilisation en spectrometrie nucleaire

    Energy Technology Data Exchange (ETDEWEB)

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

    1969-07-01

    This work studies the possibility of using high atomic number compound semiconductors, like lead telluride and cadmium telluride as to realize nuclear radiation detectors, specially in gamma ray spectrometry because of their high absorption coefficient. The problems related to the preparation of binary compounds are exposed. Experiments on PbTe show the influence of the conditions of preparation on the electrical properties of the semiconductor which are greatly dependent on the stoichiometry of the compound. PbTe surface-barrier diodes were realized and have been used to study the surface properties of this semiconductor. These diodes cannot detect nuclear radiations because of the too weak resistivity of our material. Different types of devices made of Cd Te have been studied. One of these diodes has been used as an alpha particle detector. We explain the relative poor performances of that detector by the presence of lattice defects in Cd Te where charge carriers may recombine themselves. By analysing the properties of gold diffused Cd Te diodes we identified this defect, the cadmium vacancy, the presence of which is due to the deviation from stoichiometry during the preparation of the material. (author) [French] Ce travail etudie la possibilite d'utiliser des semiconducteurs composes d'elements a numero atomique eleve, tels que le tellurure de plomb et le tellurure de cadmium pour la realisation de detecteurs de rayonnements nucleaires, grace notamment a la section efficace de capture elevee qu'ils presentent vis-a-vis des rayons gamma. On souligne les problemes relatifs a la preparation des composes binaires. Les experiences realisees sur PbTe mettent en evidence l'influence des conditions de preparation sur les proprietes electriques du semiconducteur qui dependent fortement de la stoechiometrie du compose. Nous avons realise des diodes au PbTe a barriere de surface qui ont permis de preciser les proprietes de surface de ce semiconducteur. La trop faible

  18. Development of a software for a multi-processor system aimed at the on-line control of nuclear physics experiments; Developpement de logiciel pour un systeme multiprocesseur destine au controle en ligne d'experiences de physique nucleaire

    Energy Technology Data Exchange (ETDEWEB)

    Poggioli, Jean Renaud

    1984-03-02

    This research thesis reports the development of a software for an acquisition computer aimed at the on-line control of nuclear physics experiments. An original architecture, based on the assignment of a processor to each fundamental task, enables the implementation of a high performance system. In order to make the user free of programming constraints, the author developed a software for dynamic generation of acquisition and processing codes. These codes are created from a data base which is programmed by the user by using a language close to the physical reality. Procedures of interactive control of the experiment are thus simplified by displaying function menus on the operator terminal. The author evokes possible hardware improvements and possible extensions of the system [French] Cette these rend compte du developpement logiciel realise pour un calculateur d'acquisition destine au controle en ligne d'experiences de Physique Nucleaire. Une architecture originale, basee sur l'attribution d'un processeur a chacune des taches fondamentales permet de facon simple la mise en oeuvre d'un systeme a hautes performances. Le souci de liberer l'utilisateur des contraintes de programmation a conduit a l'elaboration d'un logiciel de generation dynamique des codes acquisition et traitement; ces derniers sont crees a partir d'une base de donnees que l'experimentateur programme a l'aide d'un langage approchant la realite physique. Les procedures de controle interactif de l'experience se trouvent simplifiees par l'affichage de menus de fonctions sur la console operateur. En conclusion sont evoquees les ameliorations materielles et les extensions possibles du systeme. (auteur)

  19. Contribution to the study of nuclear fuel materials with a metallic uranium base; Contribution a l'etude des materiaux combustibles nucleaires a base d'uranium metallique

    Energy Technology Data Exchange (ETDEWEB)

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

    1957-11-15

    In a power reactor destined to supply industrially recoverable thermal energy, the most economical source of heat still consists of natural metallic uranium. However, the nuclear fuel material, most often employed in the form of rods of 20 to 40 mm diameter, is subjected to a series of stresses which lead to irreversible distortions usually incompatible with the substructure of the reactor. As a result the fuel material must possess at the outset a certain number of qualities which must be determined. Investigations have therefore been carried out, first on the technological characters peculiar to each of the three allotropic phases of pure uranium metal, and on their interactions on the stabilisation of the material which consists of either cast uranium or uranium pile-treated in the {gamma} phase. (author) [French] Dans un reacteur de puissance destine a fournir de l'energie thermique industriellement recuperable, la source de chaleur la plus economique reste constituee par de l'uranium metallique naturel. Or, le materiau combustible nucleaire, employe le plus souvent sous forme de barreaux de 20 a 40 mm de diametre, se trouve soumis a un ensemble de contraintes qui provoque des deformations irreversibles, le plus souvent incompatibles avec l'infrastructure du reacteur. Par consequent, le materiau combustible doit presenter a l'origine un certain nombre de qualites qu'il est necessaire de determiner. Aussi a-t-on d'abord etudie les caracteres technologiques propres a chacune des trois phases allotropiques de l'uranium-metal pur et leurs interactions sur la stabilisation du materiau constitue soit par de l'uranium coule, soit par de l'uranium traite en pile en phase {gamma}. (auteur)

  20. Critical experiments and nuclear calculations - LAMPRE-I; Experiences critiques et calculs nucleaires concernant le LAMPRE-I; Kriticheskie opyty i yadernye raschety - LAMPRE-I; Experimentos criticos u calculos nucleares relativos al LAMPRE-I

    Energy Technology Data Exchange (ETDEWEB)

    Battat, M E [Los Alamos Scientific Laboratory, University of California, Los Alamos, NM (United States)

    1962-03-15

    As part of a programme to develop plutonium fuels for fast-breeder reactors, the Los Alamos Scientific Laboratory has constructed and is operating a 1-MW sodium-cooled test reactor whose core contains a molten alloy of plutonium andiron (90 at. % Pu, 10 at. % Fe, m.p. 410 deg. C). Reactivity control is provided by the use of a stainless-steel reflector and four nickel control-rods located external to the core. Experiments have been performed at core temperatures (isothermal) of 80, 160 and 480 deg. C to determine critical mass and reflector worth at each of these temperatures. Control-rod worths, from period measurements, and temperature coefficient of reactivity were also measured. Calculations have been made, using the S{sub n} method for solving the neutron transport problem, to determine the basic nuclear parameters of the system. The comparison between calculated and measured values of parameters such as temperature coefficient, control-element worths, and critical mass is also of interest in evaluating the reliability of the design calculations. (author) [French] Un reacteur d'essais de 1 MW refroidi au sodium, dont le coeur contient un alliage fondu de plutonium et defer (90 at. % Pu, 10 at. % Fe, p. f. 410 deg. C), a ete construit et est en fonctionnement au Laboratoire scientifique de Los Alamos, dans le cadre d'un programme d'etudes sur les combustibles au plutonium pour reacteurs surgenerateurs a neutrons rapides. Le controle de la reactivite est assure au moyen d'un reflecteur en acier inoxydable et de quatre barres de controle en nickel, a l'exterieur du coeur. On a fait des experiences a des temperatures du coeur de 80, 160 et 480 deg. C afin de determiner la masse critique et la quantite de reflecteur qui correspond a chacune de ces temperatures. On a aussi mesure l'efficacite des barres de controle, a partir de mesures de periode, ainsi que le coefficient thermique de reactivite. Afin de determiner les parametres nucleaires de base du reacteur, on a

  1. Study of the origin of elements of the uranium-235 family observed in excess in the vicinity of the experimental nuclear EL4 reactor under dismantling. Lessons got at this day and conclusions; Etude de l'origine des elements de la famille de l'uranium-235 observes en exces dans les environs du reacteur nucleaire experimental EL4 en cours de demantelement. Enseignements retires a ce jour et conclusion

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2007-07-01

    This study resumes the discovery of an excess of actinium 227 found around by EL4 nuclear reactor actually in dismantling. The search for the origin of this excess revealed a real inquiry of investigation during three years. Because a nuclear reactor existed in this area a particular attention will have concerned this region. The doubt became the line of conduct to find the answer to the human or natural origin of this excess. Finally and against any evidence, it appears that the origin of this phenomenon was natural, consequence of the particular local geology. The detail of the different investigations is given: search of a possible correlation with the composition of elevations constituent of lanes, search (and underlining) of new sites in the surroundings of the Rusquec pond and the Plouenez station, study of the atmospheric deposits under winds of the nuclear power plant and in the east direction, search of a possible relationship with the gaseous effluents of the nuclear power plant in the past, historical study of radioactive effluents releases in the fifty last years by the analysis of the sedimentary deposits in the Saint-Herbiot reservoir, search of a possible correlation between the excess of actinium 227 and the nuclear power plant activity; search of a possible correlation with a human activity without any relationship with the nuclear activities, search of a correlation with the underground waters, search of a correlation with the geological context, collect of information on the possible transfers in direction of the food chain, determination of the radiological composition of the underground waters ( not perturbed by human activity), search of the cause of an excess of actinium 227 in the old channel of liquid effluents release of the nuclear power plant. The results are given and discussed. And contrary to all expectations the origin of the excess of actinium 227 is completely natural. (N.C.)

  2. LES of flow in the street canyon

    Science.gov (United States)

    Fuka, Vladimír; Brechler, Josef

    2012-04-01

    Results of computer simulation of flow over a series of street canyons are presented in this paper. The setup is adapted from an experimental study by [4] with two different shapes of buildings. The problem is simulated by an LES model CLMM (Charles University Large Eddy Microscale Model) and results are analysed using proper orthogonal decomposition and spectral analysis. The results in the channel (layout from the experiment) are compared with results with a free top boundary.

  3. The formation of scientists and technicians at the 'Centre d'Etudes Nucleaires' at Saclay

    International Nuclear Information System (INIS)

    Debiesse, J.

    1958-01-01

    The considerable needs in research workers and scientists which are asked by the nuclear energy obliged the Commissariat a l'Energie atomique to deal with a particular effort to increase the quantitative and qualitative formation of scientists. Most various ways have been used. 1- A National Institute of Nuclear Sciences and Nuclear Techniques was created, by a joint decree of the Prime Minister and the Minister for National Education (june 18, 1957). This Institute of Higher Teaching (250 students) indulges in the following matters: atomic engineering, quantum mechanics, theory and technic of particle accelerators, special metallurgy, radiobiology, thermic and mechanics of fluids. 2- An associated centre of the 'Conservatoire National des Arts et Metiers' was created (200 students) for technical assistants, drawers, etc. 3- In contribution with both electronic industry and Ministry of Work, the Centre d'Etudes Nucleaires contributes to an accelerated formation of technical assistants into Professional Centres. Conclusion: Training of scientists and research workers is one of the most important activities of the Centre d'Etudes Nucleaires de Saclay. Without losing its technical efficiency, it has supplied and varied means adapted to the various purposes that we shall reach. (author) [fr

  4. Analytic index for nuclear physicians uses; Repertoire analytique a l'usage des physiciens nucleaires

    Energy Technology Data Exchange (ETDEWEB)

    Ballini, R.; Barloutaud, R.; Bernas, R.; Bretonneau, P.; Chaminade, R.; Cohen, R.; Conjeaud, M.; Cotton, E.; Faraggi, H.; Grjebine, T.; Joffre, H.; Laboulaye, H. de; Lesueur, C.; Leveque, A.; Moreau, J.; Naggiar, V.; Papineau, L.; Prugne, P.; Schuhl, C.; Studinowski, FJ.; Netter, F.; Raievski, V.; Valladas, G. [Commissariat a l' Energie Atomique, Lab. du Fort de Chatillon, Fontenay-aux-Roses (France). Centre d' Etudes Nucleaires; Marty, N.; Renard, G. [College de France, Lab. de Chimie Nucleaire (France)

    The problem of the documentation in nuclear physics becomes constantly more complex. Every week brings its share of new publications, always more numerous and more varied. To remedy to this facts that we tried, in the service of Nuclear Physics of the CEA, to give to the documentation a character of a collective and systematized work. The present report covers the literature appeared between first January 1950 and first July 1951. (Volume 1: CEA report number 120; Volume 2: CEA report number 184). (M.B.) [French] Le probleme de la documentation en physique nucleaire devient sans cesse plus complexe. Chaque semaine apporte son lot de publications, toujours plus nombreuses et plus diversifiees. C'est pour essayer de porter remede a cet etat de choses que nous avons essaye, au service de Physique Nucleaire du C.E.A., de donner a la documentation le caractere d'un travail collectif systematise. Le present rapport couvre la litterature parue entre le premier Janvier 1950 et le premier Juillet 1951. (Tome 1: Rapport CEA numero 120; Tome 2: Rapport CEA numero 184). (M.B.)

  5. Les barrages alpins

    Directory of Open Access Journals (Sweden)

    Alain Marnezy

    2009-03-01

    Full Text Available Les barrages-réservoirs de montagne ont été réalisés initialement dans les Alpes pour répondre à la demande d’énergie en période hivernale. Une certaine diversification des usages de l’eau s’est ensuite progressivement développée, en relation avec le développement touristique des collectivités locales. Aujourd’hui, la participation des ouvrages d’Électricité De France à la production de neige de culture représente une nouvelle étape. Dans les régions où les aménagements hydroélectriques sont nombreux, les besoins en eau pour la production de neige peuvent être résolus par prélèvements à partir des adductions EDF. Les gestionnaires de stations échappent ainsi aux inconvénients liés à la construction et à la gestion des « retenues collinaires ». Cette évolution, qui concerne déjà quelques régions alpines comme la haute Maurienne ou le Beaufortin, apparaît comme une forme renouvelée d’intégration territoriale de la ressource en eau.Mountain reservoirs were initially built in the Alps to meet energy needs in the winter. A certain diversification in the uses of water then gradually developed, related to tourism development in the local communities. Today, the use of facilities belonging to EDF (French Electricity Authority to provide water for winter resorts to make artificial snow represents a new phase. By taking water from EDF resources to supply snow-making equipment, resort managers are thus able to avoid the problems related to the construction and management of small headwater dams. This new orientation in the use of mountain water resources already affects a number of alpine regions such as the Upper Maurienne valley and Beaufortain massif and represents a renewed form of the territorial integration of water resources.

  6. Experimental Model of Spinal Cord Injury (SCI in rats: management guidelines Modelo Experimental de Lesión de Médula Espinal (SCI en ratas: guías de manejo Modelo Experimental de Lesão Medular (SCI em ratos: diretrizes de manejo

    Directory of Open Access Journals (Sweden)

    Asdrubal Falavigna

    2013-01-01

    Full Text Available Surgical experiments with laboratory animals are necessary for medical research. These studies aim to clarify the mechanism of disease, investigate the action and efficacy of new drugs or biological markers, as well as develop and enhance new therapies and apply new techniques. Regarding the models of spinal cord injury (SCI, there are several different methods that address the handling of the animals, especially concerning the use of analgesics, antibiotics and pre- and postoperative management. The lack of uniformity and standardization among the studies does not allow the understanding of the model of SCI or the proper handling of the paraplegic animals, hampering the adequate interpretation and comparison of results. The goal of this study is to establish a standard protocol on the handling of animals subjected to experimental models of SCI.La realización de experimentos quirúrgicos con animales de laboratorio son necesarios para la investigación médica. Estos estudios tienen por objeto aclarar el mecanismo de las enfermedades, investigar la acción de nuevos medicamentos y marcadores biológicos, así como desarrollar y mejorar nuevas terapias y aplicar nuevas técnicas. En cuanto a los modelos animales de lesión de la médula espinal (SCI, existen varios métodos diferentes que abordan el cuidado de estos animales, especialmente en relación con el uso de analgésicos, antibióticos y manejo pre y post operatorio. La falta de uniformidad y estandarización entre los estudios no permite la comprensión del modelo de SCI o el manejo adecuado del animal parapléjico, lo que dificulta la interpretación y comparación adecuada de los resultados. El objetivo de este estudio es establece un protocolo estándar de manejo de animales sometidos a modelos experimentales de SCI.Experimentações cirúrgicas em nível laboratorial com o uso de animais são necessárias para o desenvolvimento da pesquisa médica. Estes estudos têm o objetivo de

  7. Les Mayas à Hollywood.

    Directory of Open Access Journals (Sweden)

    Boris Jeanne

    2007-02-01

    Full Text Available Les Mayas de nos jours ce sont surtout des grandes pyramides au milieu de la forêt à un jet d’avion de Cancún : pour nombre de touristes américains et européens, c’est une occasion de s’acoquiner avec la culture, la grande culture des civilisations perdues, en continuant de boire des piña coladas le soir au bord de la plage. Et puis au mois de décembre les Mayas ont débarqué en force dans le paysage culturel local des Américains et des Européens, dans leurs cinémas, au moyen de deux films in...

  8. Les mots du jazz

    OpenAIRE

    Roueff, Olivier

    2007-01-01

    L’ouvrage d’André Schaeffner constitue la première analyse savante du jazz (1926). Il a marqué une étape importante dans le processus de réinvention du jazz en France en contribuant notamment, par sa réception et les polémiques qu’il a suscitées, à transformer l’identification du jazz d’une musique « américaine » à une musique « noire-américaine » (c’est-à-dire aux « racines » africaines). Les analyses proposées dans cet ouvrage, alors qu’elles désignaient des musiques que la critique de jazz...

  9. Les Cahiers du CREAD

    African Journals Online (AJOL)

    Admin

    politique de bas prix exercée par la Russie et le Qatar vient confirmer ce constat ; s'ajoute à cela l'entrée éventuelle du gaz non conven- tionnel, dont son prix actuel de 3/4 $US, offre aux USA l'opportunité d'être exportateur de ..... les compagnies à produire en matière du gaz naturel, tels le prix du gaz naturel, le prix des ...

  10. Les Tinamous. Tinami

    NARCIS (Netherlands)

    Schlegel, H.

    1880-01-01

    Les Tinamous forment une tribu d’oiseaux parfaitement isolée et circonscrite, et bornée à la partie de l’Amérique comprise entre le Mexico méridional et la Patagonie. Ils se rattachent, toutefois, naturellement à l’ordre des Gallinae, tout en offrant certaines affinités avec l’ordre des Autruches.

  11. les racines du gnosticisme

    African Journals Online (AJOL)

    5 déc. 2003 ... gonies orphiques, au vrai peu populaires, comprenaient trop d'éléments asia- tiques pour pouvoir être ..... n'est pas celle, intensément existentielle: 'Que dois-je faire pour être sauvé de mes péchés? ... thèmes astrologiques et magiques, des traditions égyptiennes.28 Dans les. Diagrammes Ophites, autre ...

  12. Les Cahiers du CREAD

    African Journals Online (AJOL)

    Admin

    6 juil. 2007 ... La problématique du développement du secteur de l'artisanat en. Algérie a été très peu abordée par les chercheurs, qu'ils soient universitaires ou .... La loi a institué une taxe d'apprentissage dont le taux a été fixé à. 1% de la ...

  13. Les Cahiers du CREAD

    African Journals Online (AJOL)

    Admin

    aux intérêts objectifs de leurs auteurs sans avoir été expressément conçue à cette fin » (Bourdieu P, (1980). Questions de sociologie, éd, Minuit, Paris, p119). De ce point de vue, notre objectif est de proposer une définition opérationnelle propre, touchant ...... les années comme critères de recrutement pour deux différents.

  14. Les Fleurs bleues (R. Queneau

    Directory of Open Access Journals (Sweden)

    Séverine Manhaval

    1999-09-01

    « neo-Babelian ». All languages pervade and correspond with one another. Each of them brings its own contribution to the language of the book and together, they progressively unveil the scientific and philosophical extensions of the latter. Thus does Queneau elaborate his own linguistic and literary system, in the experimental arch of the novel, where the future language is in gestation.As he takes up Noah's torch, the writer takes his readers on a crossing the deluge in which dream and reality are intermingled, as well as humour and nostalgia for the one original language, or the virtuosity of style and rigour of composition. The novel dismantles the geographical and historical borderlines and thus transforms Noah into a new figure of the artist, who saves and rebuilds the Verb, and praises the infinite potentiality of language. Its aesthetics is grounded on the dialectic of constraint and freedom, deconstruction and reconstruction, based on a lively and scathing style. The storywriter, the poet and the mathematician meet and put their wisdom in common in this complex and bewildering novel, the roman à clef of a deep and original linguistic experiment.Les Fleurs bleues, novela publicada en 1965, propone un viaje fascinante por el tiempo y el espacio geográfico de los idiomas, una odisea por el centro de la problemática babeliana, de la que se hace el portavoz. Queneau juega con los particularismos linguísticos, los idiolectas y las sintaxis, en una perspectiva transhistórica y cosmopólita, creando un nuevo esperanto novelesco : el « neo-babeliano ». Todos los idiomas se interpenetran y se corresponden, enriquecen la escritura de la obra y revelan poco a poco sus prolongamientos a la vez cientificos y filosóficos. Queneau elabora así su proprio sistema linguistico y literario, en este laboratorio del area novelesca, donde el idioma futuro está en gestación.Reemprendiendo la obra de Noé, el escritor arrastra a sus lectores en una travesía del

  15. Les tactiques de Chronos

    CERN Document Server

    Klein, Etienne

    2009-01-01

    Nous ne doutons pas de l'existence du temps, qui demeure pourtant un objet introuvable. Nous voyons, entendons, goûtons, touchons dans le temps, mais non le temps lui-même. Il concerne toute chose, contraint tout, mais de quelle façon ? Est-il apparu en même temps que l'univers ou l'a t-il précédé ? Est-il dans le monde ou le contient-il ? S'écoule-t-il en sens unique ? Serait-ce la mort qui nous obligerait à penser le temps ? Au XXe siècle, la physique a bouleversé notre conception du temps et en vient à effleurer des questions jusque la façon dont l'homme choisit de vivre et de se vivre. Quelles sont les convergences et les différence entre le temps physique et le temps sensible, existentiel ? Pour éclairer les paradoxes, répondre aux questions, Etienne Klein puise, en contrepoint de la physique, dans la philosophie, la psychologie, la littérature, ma poésie... et le sport.

  16. Contribution to the theoretical and experimental study of the electron-volt effect in N-P junctions; Contribution a l'etude theorique et experimentale de l'effet electronvoltaique dans les jonctions N-P

    Energy Technology Data Exchange (ETDEWEB)

    Nguyen Van, Dong [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1959-07-15

    , taking into account other phenomena which occur at low temperature. In the fourth part, results concerning the healing of the defects and protection measures against too energetic {beta} rays are described. A healing difference was observed between the lifetime and the conductivity. Finally, interesting results were obtained from experiments using a cadmium sulphide film to transform the {beta} particles of {sup 90}Sr-{sup 90}Y into photons. (author) [French] Le but propose dons le cadre de ce travail est d'etudier le comportement d'une jonction semi-conductrice sous l'action des rayons {beta}. L'etude a porte d'une part sur la conversion directe de l'energie rayonnee par une source radioactive en energie electrique utilisable a l'aide des jonctions N-P, et d'autre part sur la cinetique des defauts produits dans les cristaux de semi-conducteur par les rayons {beta} de grande energie. Dans la premiere partie du travail, on a essaye de completer les theories anterieures de l'effet electron-voltaique dans les jonctions en faisant une analyse mathematique de l'effet. Ceci a permis d'atteindre une equation unique dans laquelle figurent les parametres electriques et geometriques du semi-conducteur, de la jonction et les proprietes du rayonnement incident. D'autre part, on a etudie d'une maniere plus approfondie le courant de diffusion des porteurs de charge crees par le bombardement en tenant compte de tous les facteurs intervenant dans l'expression de l'efficacite de collection de charge d'une jonction. Dans la deuxieme partie, ou des experiences d'irradiation des jonctions N-P ont ete effectuees avec une source de {sup 90}Sr- {sup 90}Y, on a signale l'interet particulier d'une jonction d'arseniure de gallium susceptible de travailler a des temperatures relativement elevees (voisines de 100 deg. C). La troisieme partie presente l'etude des defauts crees dans un cristal de semi-conducteur par les rayons {beta} de grande energie, selon la methode de l'effet electron

  17. Contribution to the theoretical and experimental study of the electron-volt effect in N-P junctions; Contribution a l'etude theorique et experimentale de l'effet electronvoltaique dans les jonctions N-P

    Energy Technology Data Exchange (ETDEWEB)

    Nguyen Van, Dong [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1959-07-15

    , taking into account other phenomena which occur at low temperature. In the fourth part, results concerning the healing of the defects and protection measures against too energetic {beta} rays are described. A healing difference was observed between the lifetime and the conductivity. Finally, interesting results were obtained from experiments using a cadmium sulphide film to transform the {beta} particles of {sup 90}Sr-{sup 90}Y into photons. (author) [French] Le but propose dons le cadre de ce travail est d'etudier le comportement d'une jonction semi-conductrice sous l'action des rayons {beta}. L'etude a porte d'une part sur la conversion directe de l'energie rayonnee par une source radioactive en energie electrique utilisable a l'aide des jonctions N-P, et d'autre part sur la cinetique des defauts produits dans les cristaux de semi-conducteur par les rayons {beta} de grande energie. Dans la premiere partie du travail, on a essaye de completer les theories anterieures de l'effet electron-voltaique dans les jonctions en faisant une analyse mathematique de l'effet. Ceci a permis d'atteindre une equation unique dans laquelle figurent les parametres electriques et geometriques du semi-conducteur, de la jonction et les proprietes du rayonnement incident. D'autre part, on a etudie d'une maniere plus approfondie le courant de diffusion des porteurs de charge crees par le bombardement en tenant compte de tous les facteurs intervenant dans l'expression de l'efficacite de collection de charge d'une jonction. Dans la deuxieme partie, ou des experiences d'irradiation des jonctions N-P ont ete effectuees avec une source de {sup 90}Sr- {sup 90}Y, on a signale l'interet particulier d'une jonction d'arseniure de gallium susceptible de travailler a des temperatures relativement elevees (voisines de 100 deg. C). La troisieme partie presente l'etude des defauts crees dans un cristal de

  18. Study and installation of concrete shielding in the civil engineering of nuclear construction (1960); Etude et mise en place des betons de protection dans le genie civil des ouvrages nucleaires (1960)

    Energy Technology Data Exchange (ETDEWEB)

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

    1960-07-01

    sont decrites telles qu'elles ont ete realisees au Centre d'Etudes Nucleaires de Saclay. Des specifications sont donnees pour les betons de barytine et pour la fabrication des blocs de protection du synchrotron a protons 'Saturne'. (auteur)

  19. Study and installation of concrete shielding in the civil engineering of nuclear construction (1960); Etude et mise en place des betons de protection dans le genie civil des ouvrages nucleaires (1960)

    Energy Technology Data Exchange (ETDEWEB)

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

    1960-07-01

    etudes, deux applications pratiques sont decrites telles qu'elles ont ete realisees au Centre d'Etudes Nucleaires de Saclay. Des specifications sont donnees pour les betons de barytine et pour la fabrication des blocs de protection du synchrotron a protons 'Saturne'. (auteur)

  20. As bases experimentais da lesão por isquemia e reperfusão do fígado: revisão The experimental basis of hepatic ischemia-reperfusion injury: review

    Directory of Open Access Journals (Sweden)

    Luiz Eduardo C. Miranda

    2004-01-01

    Full Text Available O transplante hepático tornou-se o procedimento de escolha para o tratamento da doença hepática terminal. Não obstante o sucesso da cirurgia, a disfunção pós-operatória do fígado enxertado ainda representa importante causa de morbidade e mortalidade. O restabelecimento do fluxo sangüíneo ao fígado recém transplantado impõe a ele nova agressão, agravando a lesão causada pelo período de isquemia. Este fenômeno pouco compreendido é conhecido como lesão por isquemia e reperfusão e envolve disfunção endotelial, seqüestro de leucócitos e agregação de plaquetas, lesão por radicais livre de oxigênio, e distúrbios da microcirculação hepática. Essa revisão discute os vários aspectos fisiopatológicos que estão envolvidos na lesão por isquemia e reperfusão do fígado.Hepatic transplantation has become the main treatment for patients with terminal hepatic disease. Whatever the success of such surgery, the hepatic dysfunction associated with liver transplantation is an important cause of morbidity and mortality. Paradoxically, on restoring the blood supply, the liver is subjected to a further insult, aggravating the injury already caused by ischemia. This complex phenomenon is termed ischemia-reperfusion injury and involves endothelial cell dysfunction, leukocyte entrapment, platelet aggregation, oxidant stress and hepatic microcirculatory perfusion failure. This review discusses the physiopathlogicals mechanisms of liver ischemia-reperfusion injury.

  1. Nuclear Calculations of Light-Water Moderated Reactors and Experimental Correlations; Calculs de Riacteurs Ralentis a l'Eau Ordinaire et Comparaison avec les Risultats Expirimentaux; Raschet reaktorov s zamedlitelem iz obychnoj vody i sravnenie s ehksperimental'nymi rezul'tatami; Calculos Nucleares de Reactores Moderados por Agua Ligera y Correlacion Experimental

    Energy Technology Data Exchange (ETDEWEB)

    Solanilla, R. [Comision Nacional de Energia Atomica, Buenos Aires (Argentina)

    1964-02-15

    and experimental reactivity. (author) [French] En appliquant la theorie a deux groupes modifiee pour tenir compte des fissions epithermiques, on a analyse une serie d'assemblages critiques avec reflecteur et ralentisseur a l'eau ordinaire, qui differaient par le degre d'enrichissement en {sup 235}U. Les sections efficaces du groupe thermique sont celles qui figurent dans les tables d'Amster pour les melanges hydrogenes a differentes temperatures et pour differentes concentrations de {sup 235}U et des absorbants en l/v. L'effet de l'heterogeneite des sections efficaces a ete traite approximativement en modifiant la concentration de l'absorbant par variation spatiale du flux thermique dans la cellule. On a calcule le facteur de desavantage en appliquant la formule d'Amouyal-Benoist. Par definition, le coefficient de diffusion thermique est l'inverse du triple de la section efficace macroscopique de transport, homogeneise sur tout le volume de la cellule. On a calcule les constantes du groupe rapide conformement au systeme d'Ombrellaro a trois groupes rapides de diffusion (de 10 MeV a 0,821 MeV; de 0,821 MeV a 5,5 keV; 5,5keV a 0,625 eV) avec des sections efficaces microscopiques adaptees a chaque groupe. La definition que donne Ombrellaro pour les constantes neutioniques des trois groupes rapides en fonction des sections efficaces ajustees a ete modifiee pour le troisieme groupe conformement au traitement de l'absorption effective de resonance de {sup 238}U, proposee par Hick, et fondee sur le calcul de l'integrale de resonance effective. On a calcule l'integrale de resonance effective de {sup 238}U a l'aide de la formule deduite de la theorie par l'auteur, la relation S/M etant reduite conformement a l'approximation de Bell pour l'effet 'Dancoff' . La correlation entre les resultats du calcul et les donnees experimentales disponibles - qui correspondent a de nombreuses valeurs pour les caracteristiques du ralentisseur et pour la composition des matieres et a de

  2. Papel do óxido nítrico no desenvolvimento de lesões cardíacas na fase aguda da infecção experimental pelo Trypanosoma cruzi Role of nitric oxide in the development of cardiac lesions during the acute phase of experimental infection by Trypanosoma cruzi

    Directory of Open Access Journals (Sweden)

    Cláudia Renata Bibiano Borges

    2009-04-01

    Full Text Available A doença de Chagas é causada pelo Trypanosoma cruzi e o coração é o órgão mais acometido. O óxido nítrico apresenta importante ação anti-Trypanosoma, porém, com pouca evidência de seu papel no mecanismo de lesão tecidual. O objetivo deste estudo foi analisar a contribuição do óxido nítrico no desenvolvimento da inflamação e da fibrose cardíaca na fase aguda da infecção experimental por cepas Y e Colombiana do Trypanosoma cruzi. A inflamação foi significativamente maior nos animais infectados pela cepa Colombiana, comparada com os infectados com a cepa Y, tanto nos animais C57BL/6 (3,98x1,87%; p=0,004 quanto nos animais C57BL/6 deficientes na sintase do óxido nítrico induzível (3,99x2,4%; p=0,013. O parasitismo cardíaco dos animais C57BL/6 deficientes na sintase do óxido nítrico induzível infectados pela cepa Colombiana foi significativamente maior que o destes mesmos animais infectados com a cepa Y (2,78x0,17 ninhos/mm²; p=0,004 assim como, os animais C57BL/6 infectados com a cepa Colombiana (2,78x1,33 ninhos/mm²; p=0,006 ou cepa Y (2,78x0,53 ninhos/mm²; p=0,005. Os dados reforçam o papel do óxido nítrico no controle do parasitismo e sugerem seu papel na proteção tecidual, controlando a inflamação e potencialmente diminuindo lesões cardíacas durante a fase aguda na doença de Chagas experimental.Chagas disease is caused by Trypanosoma cruzi and the heart is the organ most affected. Nitric oxide has notable anti-Trypanosoma action, but with little evidence regarding its role in the mechanism for tissue injury. The objective of this study was to analyze the contribution of nitric oxide towards the development of inflammation and cardiac fibrosis during the acute phase of experimental infection by Y and Colombian strains of Trypanosoma cruzi. The inflammation was significantly more intense in animals infected with the Colombian strain, compared with those infected with the Y strain, both in C57BL/6

  3. Chemical elimination of alumina in suspension in nuclear reactors heavy water; Elimination de l'alumine en suspension dans l'eau lourde des reacteurs nucleaires par voie chimique

    Energy Technology Data Exchange (ETDEWEB)

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

    1967-02-01

    Corrosion of aluminium in contact with moderating water in nuclear reactor leads to the formation of an alumina hydrosol which can have an adverse effect on the operation of the reactor. Several physical methods have been used in an attempt to counteract this effect. The method proposed here consists in the elimination of the aluminium by dissolution and subsequent fixation in the ionic form on mixed-bed ion-exchange resin. In order to do this, the parameters and the values of these parameters most favorable to the dissolution process have been determined. If the moderator is heavy water, the deuterated acid can be prepared by converting a solution in heavy water to a salt of the acid using a deuterated cationic resin. (author) [French] La corrosion de l'aluminium au contact de l'eau moderatrice des reacteurs nucleaires, donne lieu a la formation d'un hydrosol d'alumine nuisible au bon fonctionnement des reacteurs. Plusieurs methodes physiques ont ete mises en oeuvre pour pallier ces inconvenients. On propose ici d'eliminer l'alumine par solubilisation pour la fixer ensuite sous forme ionique par des resines echangeuses d'ions, en lit melange. A cette fin on determine les parametres et leurs grandeurs favorables a cette solubilisation. Si le moderateur est de l'eau lourde la preparation d'acide deutere peut etre effectuee par passage d'une solution en eau lourde a un sel de l'acide sur resine cationique deuteree.

  4. Case Study in Internal Audit of Nuclear Material; Etude d'un Systeme de Verification Comptable Interne des Matieres Nucleaires; Izuchenie primera organizatsii vnutrennego ucheta yadernykh materialov na predpriyatii; Estudio de la Fiscalizacion Interna de los Materiales Nucleares

    Energy Technology Data Exchange (ETDEWEB)

    Kops, S. [United States Atomic Energy Commission, Argonne, IL (United States)

    1966-02-15

    sont generalement les principaux facteurs a considerer lorsque l'on veut determiner s'il y a lieu d'etablir un systeme classique de verification comptable interne. L'auteur analyse les besoins et les caracteristiques d'un systeme de verification comptable interne dans le cas particulier d'une organisation qui manipule des matieres brutes ou des produits fissiles speciaux (matieres nucleaires), en les confrontant a ceux d'un systeme de verification classique. Il montre comment, etant donne le prix eleve et la valeur strategique des matieres, il est necessaire d'etablir un systeme special de verification comptable. Le memoire etudie en detail l'organisation du systeme de verification comptable interne dans une installation produisant des matieres nucleaires; il indique notamment comment fixer la date des controles et comment proceder a la verification des livres et inventaires. Il indique egalement la competence et les qualifications professionnelles que doit avoir le personnel charge de la verification comptable, ainsi que les considerations d'ordre statistique a appliquer pour determiner les donnees qui devront faire l'objet d'une verification. Le memoire decrit de facon detaillee la maniere dont ces dispositions sont appliquees dans la pratique de la verification comptable interne. Il indique les modifications qui peuvent etre apportees aux normes etablies ainsi que les differentes manieres d'envisager le probleme de la verification des comptes et montre que, s'il est possible dans le cas d'autres fabrications de proceder simplement a une verification comptable des stocks, il est necessaire dans l'industrie nucleaire de proceder effectivement a l'inventaire materiel du stock. Le memoire presente les divers moyens utilises pour communiquer les resultats de la verification interne. La presentation du rapport comptable et sa teneur sont determinees en fonction des besoins des differents services. Le memoire indique les diverses manieres dont le rapport comptable peut

  5. Association "Les Simples"

    OpenAIRE

    Thouzery, Michel

    2014-01-01

    Fondée par les producteurs du Syndicat Inter-Massifs pour la Production et l’Économie des Simples (S.I.M.P.L.E.S), l’association base son action sur la recherche et le maintien d’une production de qualité (herboristerie et préparations à base de plantes) qui prend en compte le respect de l’environnement et la pérennité des petits producteurs en zone de montagne. Actions de formation Stages de découverte de la flore médicinale sauvage, Stages de culture et transformation des plantes médicinale...

  6. Les perspectives nutritionnelles offertes par les OGM en alimentation humaine

    Directory of Open Access Journals (Sweden)

    Pascal Gérard

    2004-03-01

    Full Text Available Une étude des brevets récents, des publications scientifiques ainsi que des documents présentant les projets des firmes de biotechnologie constituent la base de cet article qui présente les perspectives de développement en alimentation humaine des organismes génétiquement modifiés (OGM présentant un intérêt nutritionnel. Si l’on trouve dans les brevets et les publications scientifiques des applications qui concernent l’amélioration ou l’enrichissement de la composition en macro- et micronutriments, ces applications restent curieusement à l’état de projets, très loin de la mise sur le marché. Les critiques aussi bien que les louanges dont sont l’objet les rares cas dont on pourrait envisager une mise en œuvre à moyen terme, comme le « riz doré », sont aussi injustifiées et excessives les unes que les autres. Les violentes polémiques autour des OGM risquent de handicaper le développement d’une technique puissante, qui n’est certes pas indispensable pour apporter une solution à l’éradication de la faim dans le monde, mais qui peut apporter des améliorations à la nutrition des populations, aussi bien des populations des pays en développement que des pays développés.

  7. Archives: les cahiers du cread

    African Journals Online (AJOL)

    Items 1 - 24 of 24 ... Archives: les cahiers du cread. Journal Home > Archives: les cahiers du cread. Log in or Register to get access to full text downloads. Username, Password, Remember me, or Register · Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current Issue · Archives. 1 - 24 of 24 Items. 2016 ...

  8. Traumatic brain injury: clinical and pathological parameters in an experimental weightdrop model Lesão cerebral traumática: parâmetros clínicos e patológicos em um modelo experimental de queda de peso

    Directory of Open Access Journals (Sweden)

    Danilo dos Santos Silva

    2011-04-01

    Full Text Available PURPOSE: To investigate the function of an experimental cranium trauma model in rats. METHODS: The equipment, already described in the literature and under discreet adaptations, is composed by a platform that produces closed head impact controlled by weight drop with pre-defined and known energy. 25 Wistar male rats (Rattus norvegicus albinus were divided into five equal groups that received different quantities of cranial impact energy: G1, G2, G3 and G4 with 0,234J, 0,5J, 0,762J and 1J respectively and G5 (Sham. Under intense analgesia, each group was evaluated clinically in a sequence of intervals and had their encephalon removed for pathologic analysis. RESULTS: Important clinical alterations (convulsions, bradycardia, bradypnea and abnormal postures and focal pathologic (hematomas and hemorrhages kept proportion with the intensity of the impact. No fracture was observed and the group 4 had 80% mortality rate. CONCLUSION: The experimental cranium trauma animal model by weight drop is an alternative of low cost and easy reproduction that allows evaluating clinical and pathological alterations in accordance with studies in experimental surgery aims for new traumatic brain injury approach in rats.OBJETIVO: Investigar o uso de um modelo de trauma craniano experimental em ratos. MÉTODOS: O equipamento, já descrito na literatura e sob discretas adaptações, contitui-se de uma plataforma para produção de lesão craniana fechada controlada por queda de peso com energia pré-definida e conhecida. 25 ratos Wistar machos (Rattus norvegicus albinus foram divididos em cinco grupos iguais que receberam níveis diferentes de energia de impacto craniano: G1, G2, G3 e G4 com 0,234J, 0,5J, 0, 762J e 1J respectivamente e G5 (Sham. Sob intensa analgesia, cada grupo foi avaliado clinicamente em uma seqüência de intervalos e tiveram seus encéfalos removidos para análise patológica. RESULTADOS: Alterações clínicas importantes (convulsões, bradicardia

  9. Utilisation de l'essai comete et du biomarqueur gamma-H2AX pour detecter les dommages induits a l'ADN cellulaire par le 5-bromodeoxyuridine post-irradiation

    Science.gov (United States)

    La Madeleine, Carole

    Ce memoire est presente a la Faculte de medecine et des sciences de la sante de l'Universite de Sherbrooke en vue de l'obtention du grade de maitre es sciences (M.Sc.) en radiobiologie (2009). Un jury a revise les informations contenues dans ce memoire. Il etait compose de professeurs de la Faculte de medecine et des sciences de la sante soit : Darel Hunting PhD, directeur de recherche (departement de medecine nucleaire et radiobiologie), Leon Sanche PhD, directeur de recherche (departement de medecine nucleaire et radiobiologie), Richard Wagner PhD, membre du programme (departement de medecine nucleaire et radiobiologie) et Guylain Boissonneault PhD, membre exterieur au programme (departement de biochimie). Le 5-bromodeoxyuridine (BrdU), un analogue halogene de la thymidine reconnu depuis les annees 60 comme etant un excellent radiosensibilisateur. L'hypothese la plus repandue au sujet de l'effet radio sensibilisant du BrdU est qu'il augmente le nombre de cassures simple et double brin lorsqu'il est incorpore dans l'ADN de la cellule et expose aux radiations ionisantes. Toutefois, de nouvelles recherches semblent remettre en question les observations precedentes. Ces dernieres etudes ont confirme que le BrdU est un bon radiosensibilisateur, car il augmente les dommages radio-induits dans l'ADN. Mais, c'est en etant incorpore dans une region simple brin que le BrdU radiosensibilise l'ADN. Ces recherches ont egalement revele pour la premiere fois un nouveau type de dommages produits lors de l'irradiation de l'ADN contenant du BrdU : les dimeres interbrins. Le but de ces travaux de recherche est de determiner si la presence de bromodeoxyuridine dans l'ADN augmente l'induction de bris simple et / ou double brin chez les cellules irradiees en utilisant de nouvelles techniques plus sensibles et specifiques que celles utilisees auparavant. Pour ce faire, les essais cometes et la detection des foci H2AX phosphorylee pourraient permettre d'etablir les effets engendres par

  10. The 9. European nuclear conference; La 9. conference nucleaire europeenne

    Energy Technology Data Exchange (ETDEWEB)

    Maurel, V.; Lewis, D.; Smirnov, V.P.; Gutierrez, J.E.; Paulin, Ph.; Markov, D.V.; Smirnov, A.V.; Polenok, V.S.; Horhoianu, G.; Olteanu, G.; Van der Schaaf, B.; Gavillet, D.; Lapena, J.; Ohms, C.; Roth, A.; Van Dyck, St.; Mardon, J.P.; Thomas, A.; Cipiere, M.F.; Faidy, C.; Hedin, F.; Delnondedieu, M.; Chassignole, B.; Doudet, L.; Dupond, O.; Kang, K.; Park, K.; Kim, K.; Ha, J.; Hoon-Seok, Jung; Yong-koo, Lee; Kwang-Ho, Kim; Seungwoo, Paek; Heui-Joo, Choi; Do-Hee, Ahn; Kwang-Rag, Kim; Minsoo, Lee; Sung-Paal, Yim; Hongsuk, Chung; Detroux, P.; Meessen, O.; Defloor, J.; Lars-Erik, Holm; Barescut, J.C.; Vacquier, B.; Laurier, D.; Caer, S.; Quesne, B.; Oudalova, A.; Geras' kin, St.; Dikarev, V.; Dikareva, N.; Chernonog, E.; Yang-Geun, Chung; Gab-Bock, Lee; Sun-Young, Bang; Yong-Sun, Lee; Bolognese-Milsztajn, T.; Frank, D.; Lacoste, V.; Pihet, P.; Lacronique, J.F.; Chauliac, C.; Verwaerde, D.; Pavageau, O.; Zaetta, A.; Varaine, F.; Warin, D.; Hudelot, J.P.; Bioux, Ph.; Klann, R.; Petruzzi, A.; D' auria, F.; Yung Kwon, Jin; Chul Jin, Chol; Mihalache, M.; Radu, V.; Pavelescu, M.; Schneidesch, Ch.R.; Jinzhao, Zhang; Dalleur, J.P.; Nuttin, A.; Meplan, O.; Wilson, J.; Perdu, F.; Campioni, G.; Mounier, C.; Sigrist, J.F.; Laine, Ch.; Broc, D.; Robbe, M.F.; Cariou, Y.; Seok-Kyun, Yoon; Win, Naing; Myung-Hyun, Kim; Kyung, Hee; Fridman, E.; Shwageraus, E.; Galperin, A.; Meplan, O.; Laulan, O.; Mechel-Sendis, F.; Belgaid, M.; Kadem, F.; Amokrane, A.; Hamidouche, T.; El-Khider, Si-Ahmed

    2005-11-15

    This issue gathers the abstracts of the papers presented at the ninth European nuclear conference (ENC-2005). The main part of the conference is split into 20 sessions. These sessions cover all technical aspects of nuclear power, from reactor design to waste management, without forgetting experimental and research reactors, reactor dismantling, economy, resources, safety, radioprotection and education issues. Perspectives of a nuclear renaissance are clearly visible in the world. This renaissance, mainly due to political, economical, societal and ecological factors, is fuelled by scientific and technical progress. This conference was the opportunity to present together these aspects of nuclear power and to analyze their mutual interactions.

  11. Fluctuations in a system depending on several random parameters. Application to reactors (1962); Fluctuations d'un systeme dependant de plusieurs parametres aleatoires. Application aux reacteurs nucleaires (1962)

    Energy Technology Data Exchange (ETDEWEB)

    Blaquiere, A [Faculte des Sciences de Paris, 75 (France); Pachowska, R [Universite Technique de Varsovie (Poland)

    1962-07-01

    We have previously developed a method for studying neutronic fluctuations in nuclear reactors using the analogy between the behaviour of a reactor and that of certain common radioelectric circuits. The fluctuations may then be calculated by introducing into the circuit a suitable noise source. By this method we have been able to consider the overall fluctuations in a particularly simple form and we have provided a physical significance for certain results obtained more laboriously by other methods. The object of the present report is to generalise this method and in particular to extend it to the case of a reactor having a cellular structure and to apply it to fluctuations within a cell. It is thus shown that the fluctuations in a cell are the resultant of two terms: - a rapidly evolving Poissonian noise, not related to the overall fluctuations; - a slowly evolving noise, when the reactor is not too far from criticality, which is related to the overall fluctuations. The first term arises from a rapid 'ordering' of the system, during which time the cells come mutually into equilibrium. The second term is due to the coordinated evolution of all the cells, after the end of the first transitory phase. The conclusions reached show that it would be useful to complete the study with an analysis of non-linear phenomena which can considerably influence the transitory behaviour of the cells during the initial pre-equilibrium phase. This report also Stresses the relationship of the new method to the old methods. It tends also to place pile fluctuation theory in a more general framework, that of the fluctuations of a system depending on several random parameters; from this point of view, the method could easily be transposed and adapted to the study of other physical problems of this type. (authors) [French] Nous avons precedemment developpe une methode d'etude des fluctuations neutroniques des reacteurs nucleaires mettant a profit l'analogie entre le comportement d

  12. The United States Atomic Energy Commission Programme of Nuclear Materials Management; Le Programme de Gestion des Matieres Nucleaires Applique par L'USAEC; Programma komissii po atomnoj ehnergii ssha v oblasti obrashcheniya s yadernymi materialami; El Programa de Administracion de Materiales Nucleares de la Comision de Energia Atomica de los Estados Unidos

    Energy Technology Data Exchange (ETDEWEB)

    George, D. E. [United States Atomic Energy Commission, Washington, DC (United States)

    1966-02-15

    Nuclear materials management as conceived by the US Atomic Energy Commission is defined and its development traced from 1943 to the present time. The general programme is outlined and its principal features discussed. Emphasis is placed on administration of those portions of the USAEC programme which pertain to the development and maintenance of quantity data, the establishment of internal controls and the evaluation of performance. The current techniques whereby transfer data are recorded and processed within the USAEC are discussed in some detail, as are the techniques for presentation of material balance reports which periodically summarize the transactions and the results of operations. The techniques used by the USAEC to ascertain the effectiveness of the nuclear materials management programmes of its operating contractors are also discussed. In addition to material being held by contractors which operate USAEC-owned plants and laboratories, there are large quantities of special nuclear material held under a wide variety of financial and administrative arrangements, e.g. under lease, private ownership, under contract with the USAEC where the user is financially liable for losses, as well as those where the risk of losses is taken by the USAEC. This divergence of circumstances causes significant variation in the emphasis and approach used by the AEC and this variation is noted. A brief summary of unresolved problem areas concludes the presentation. (author) [French] L'auteur definit la gestion des matieres nucleaires telle qu'elle est concue par l'USAEC et decrit son evolution depuis 1943 jusqu'a nos jours. Il expose le programme general et discute ses principales caracteristiques. Le memoire souligne les aspects administratifs des parties du programme qui ont trait a la preparation et la tenue a jour des donnees relatives aux quantites, a l'application de controles internes et a l'evaluation de l'efficacite des mesures prises. L'auteur commente en detail la

  13. Theoretical and experimental study of a calorimetric technique for measuring energy deposition in materials caused by complex pile irradiation; Etude theorique et experimentale d'une technique calorimetrique de mesure des depots d'energie dans les materiaux dus au rayonnement complexe de pile

    Energy Technology Data Exchange (ETDEWEB)

    Mas, P; Sciers, P; Droulers, Y [Commissariat a l' Energie Atomique. Centre d' Etudes Nucleaires, 38 - Grenoble (France)

    1962-07-01

    Calorimetric methods may be used to measure gamma fluxes greater than 10{sup 6} r/h near the cores of swimming pool reactors. The theory, design, and properties of isothermal calorimeters are discussed, and experimental results obtained with two types are presented. Measurement of energy deposition in materials and the long term integration of energy depositions are other uses of these devices. Results of measurements on heat deposition in steel and water are given. Fluxes were also measured. (authors) [French] Une premiere partie traite de la theorie des calorimetres isothermes mis en oeuvre au C.K.N. Grenoble. La puissance deposee dans le calorimetre par les flux de rayonnement echauffe celui-ci. L'echauffement est mesure a l'aide d'un thermocouple. On montre que l'on a ainsi une mesure absolue de cette puissance. Une deuxieme partie traite de l'etude experimentale de: deux types d'appareils utilises: leur construction, les resultats experimentaux, leurs utilisations. Trois de celles-ci sont particulierement interessantes: - la mesure des hauts flux gamma, - la mesure du depot d'energie dans les materiaux, - l'integration pendant une longue duree des depots d'energie (un modele de calorimetre a fonctionne a ce jour 2 500 heures et a integre 9 x 10 puissance 10 rads gamma et 6 x 10 puissance 18 neutrons rapides). La troisieme partie est consacree a l'etude des qualites de l'appareil: robustesse, fidelite, precision, sensibilite, gamme de mesure. Enfin dans la derniere partie sont decrites deux applications de la methode calorimetrique a la mesure du depot d'energie dans un acier special et dans l'eau. (auteurs)

  14. Preliminary studies on the closed cycle magneto aerodynamic converter; Etudes preliminaires sur les convertisseurs magnetohydrodynamiques fonctionnant hors d'equilibre thermodynamique

    Energy Technology Data Exchange (ETDEWEB)

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

    1964-07-01

    electron heating in argon-potassium can be achieved by magnetic fields from 1 to 2 Ts. Plans are being made to build an important facility which will work on the principle of hot shots. The gas generator will deliver cesium-seeded helium shots at a temperature of 2100 deg. K. The shot will last 1/ 10 s and the instantaneous thermal power will reach 1 MW. (author) [French] A cote des convertisseurs magnetoaerodynamiques a cycle ouvert qui transforment l'energie thermique contenue dans les gaz de combustion on etudie tres attentivement le convertisseur a cycle ferme qui peut tirer son energie de toute source de chaleur a haute temperature et tout particulierement des sources nucleaires. Avant une etude pratique de l'ensemble de la centrale les performances du convertisseur lui-meme doivent etre bien delimitees. Ces performances sont largement fonction de la conductivite du gaz utilise. Mais cette conductivite ne doit pas etre payee par une temperature techniquement inadmissible pour l'echangeur de chaleur. Dans le fluide de conversion on est amene a associer un gaz porteur, helium ou argon, et une semence facilement ionisable cesium ou potassium. L'ionisation purement thermique n'est efficace qu'a partir de 2500 deg. K, par contre le champ electrique developpe par induction dans le convertisseur peut, sous certaines conditions, accroitre la temperature electronique et developper une ionisation bien superieure a la valeur d'equilibre. Il devient alors possible d'ioniser le gaz a temperature moderee. Des travaux en cours ont pour but de preciser les conditions permettant de creer cette ionisation hors d'equilibre dans les gaz rares ensemenses. Des mesures ont ete faites a l'aide d'un plasmatron triphase do 500 kVA alimente a l'argon ensemence de potassium. On a fait debiter cet appareil dans une cellule permettant de mesurer les composantes tensorielles de la conductivite en presence de champ magnetique. Les valeurs trouvees dans les conditions d'equilibre thermodynamique

  15. Some equipment for graphite research in swimming pool reactors; Quelques dispositifs d'etude du graphite dans les piles piscines

    Energy Technology Data Exchange (ETDEWEB)

    Seguin, M; Arragon, Ph; Dupont, G; Gentil, J; Tanis, G [Commissariat a l' Energie Atomique, Grenoble (France). Centre d' Etudes Nucleaires

    1964-07-01

    The irradiation devices described are used for research concerning reactors of the natural uranium type, moderated by graphite and cooled by carbon dioxide. The devices are generally designed for use in swimming pool reactors. The following points have been particularly studied: - maximum use of the irradiation volume, - use of the simplest technological solutions, - standardization of certain constituent parts. This standardization calls for precision machining and careful assembling; these requirements are also true when a relatively low irradiation temperature is required and the nuclear heating is pronounced. Finally, the design of these devices is suitable for the irradiation of other fissile or non-fissile materials. (authors) [French] Les dispositifs d'irradiation decrits servent aux etudes relatives a la filiere des reacteurs a uranium naturel, moderes au graphite et refroidis par le gaz carbonique. Ils sont generalement concus pour etre utilises dans des piles piscines. L'accent a ete mis sur: - l'utilisation au maximum du volume d'irradiation, - le recours aux solutions technologiques les plus simples, - la standardisation de certaines parties constitutives. Cette standardisation impose un usinage precis et un montage soigne, lesquels sont egalement necessaires lorsqu'on doit obtenir une temperature d'irradiation relativement basse alors que l'echauffement nucleaire est important. Enfin, la conception de ces dispositifs est valable pour irradier d'autres materiaux non fissiles ou fissiles. (auteurs)

  16. Former les jeunes chercheurs en vue d'influencer les politiques de ...

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

    2 mai 2016 ... Les conférences, les séances de tutorat et les stages financés par le CRDI en Asie, en Afrique et en Amérique latine renforcent les capacités des jeunes chercheurs en vue d'éclairer les politiques de télécommunications. Communications Policy Research South (CPRsouth) : les conférences présentent les ...

  17. Les lueurs des sables

    CERN Multimedia

    Les lueurs des sables

    2013-01-01

    Two CERN ladies are getting ready for the “Trophée Roses des Sables” rally adventure: Julie and Laetitia are finalizing the last details before setting off on Monday 7th October 2013. Julie from EN-MEF group and Laetitia from DGS-SEE group, met at the CERN Rugby club. This year, they are participating in the 100 % female rally which will take place in Morocco from 10 to 20 October. They will be carrying along 100 kg of humanitarian donation for children such as some clothes, books and medical material. Do not hesitate to show your support at their farewell party to be held on Monday 7 October, from 4 to 6 pm in front of the St Genis-Pouilly Mairie (city Hall). Follow their exciting adventure on the blog leslueursdessables.trophee-roses-des-sables.org and on their association’s Facebook page Les Lueurs des Sables.

  18. Les Fleurs artificielles

    OpenAIRE

    Lucken, Michael

    2016-01-01

    L’image de Japonais imitateurs possède une longue histoire : en Europe, elle émerge au xviiie et a connu jusqu’à récemment différentes phases caractéristiques. Bien que liée à la modernisation, cette histoire n’éclaire pas uniquement la rencontre du Japon avec la culture européenne, elle est aussi le miroir des conceptions de l’art en Occident où des contremodèles étaient nécessaires afin de soutenir l’idée que la création est la valeur suprême. La première partie de ce livre a pour objectif ...

  19. Criteria for Special Nuclear Materials Inventory and Control Procedures; Criteres a Suivre Pour Proceder a l'Inventaire des Matieres Nucleaires Speciales et aux Mesures de Controle; Kriterii dlya inventarizatsii spetsial'nykh yadernykh materialov i metody ucheta; Criterios a Que Deben Ajustarse los Procedimientos de Inventario y Control de los Materiales Nucleares Especiales

    Energy Technology Data Exchange (ETDEWEB)

    Kinderman, E. M.; Tarrice, R. R. [Stanford Research Institute, Menlo Park, CA (United States)

    1966-02-15

    and the total inventory of these special nuclear materials. A matrix of solutions to the management and inventory control of special nuclear materials will be presented. The multiplicity and relative effectiveness of varied techniques at key stages of the materials supply, utilization and recovery are assessed. (author) [French] L'un des plus importants problemes qui, dans le domaine nucleaire et notamment dans l'exploitation commerciale de l'energie d'origine nucleaire, se posera aux societes d'investissement, aux directeursetaux exploitants est celui du controle efficace de l'inventaire des matieres nucleaires dont la valeur depassera, d'ici 1980, 5 milliards de dollars des Etats-Unis. Comparativement a la plupart des matieres utilisees commercialement, les matieres nucleaires speciales sont couteuses; aux Etats-Unis par exemple, l'uranium enrichi a 90%, l'uranium enrichi a 3% sous forme d'hexa- fluorure et l'eau lourde coutent respectivement 10808 dollars, 254 dollars et 61,60 dollars le kilo. En outre, ces matieres sont frequemment soumises, pour des raisons de protection sanitaire et de securite, a des controles gouvernementaux speciaux sans rapport direct avec leur valeur monetaire. En depit de leur prix eleve, ces matieres sont destinees a etre utilisees en grandes quantites; par exemple, on utilisera de 50 a 75 t de combustible enrichi a 3{sup o}{r_brace}o dans un reacteur de 500 MW modere a l'eau ordinaire et 200 a 300 reacteurs de cette puissance fonctionneront vraisemblablement dans le monde en 1980. L'experience acquise a permis la mise au point et l'application de methodes speciales pour le controle commercial de grandes quantites de matieres de faible valeur comme le charbon ou le minerai de fer ou de petites quantites de matieres de grande valeur comme les metaux precieux. Tout en ayant des prix comparables a ces derniers, les matieres nucleaires speciales sont de nature differente et seront utilisees en quantites beaucoup plus importantes que les

  20. Les jardins de la physique

    CERN Document Server

    Allemand, Luc

    2017-01-01

    À l'écart du monde, loin des laboratoires, en contact avec la nature, des savants réputés du monde entier viennent enseigner les grands sujets de la physique et partager les dernières avancées avec de nombreux élèves. À l'écart du monde, loin des laboratoires, en contact avec la nature, des savants réputés du monde entier viennent enseigner les grands sujets de la physique et partager les dernières avancées avec de nombreux élèves. Ces hauts-lieux sont propices à la méditation et procurent autant d'opportunités de rencontres et d'échanges. La liberté de pensée qui y règne permet d'explorer de nouvelles pistes pour la physique de demain. Car les grandes découvertes surviennent rarement comme des illuminations : elles résultent plutôt de lentes maturations, accompagnées de travail acharné et de discussions suivies. De tels lieux existent depuis les années 1950 en France : l'Institut d'Études scientifiques de Cargèse, en Corse, et l'École de Physique des Houches, dans les Alpes, ...

  1. Experimental study of heat transfer and pressures drops for cans with spiral herring-bone fins; Etude experimentale du transfert de chaleur et des pertes de charges des gaines a ailettes helicoidales en chevron

    Energy Technology Data Exchange (ETDEWEB)

    Pelce, J; Francois, S; Houseaux, O; Pierre, B [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1964-07-01

    Cans fitted with herring-bone fins are used for cooling uranium in certain nuclear reactor. By herring-bone is meant a staggered arrangement of the fins which have a plane of symmetry parallel to the general direction of liquid flow. The main geometrical parameter are then: the number of fins, the number of herring-bones, the angle of inclination of the fins with respect to the can axis, the dimensions of the fins, the can diameter and the channel diameter. The research is essentially experimental. The test are of three types: full size tests, in conditions approaching those in the reactor (constant flux, CO{sub 2} under pressure); full size tests but with a constant wall temperature, much easier to set up, and intended to distinguish rapidly between the merits of the various types of can; large-scale tests with air at atmospheric pressure for studying the phenomena in more detail. For each can tried out there is a corresponding pressure drop coefficient, a mean thermal exchange coefficient Mo-bar and a minimum exchange coefficient Mo{sub min} and Mo-bar are related by the expression Mo{sub min} = Mo-bar * f{sub c} * f, where f{sub c} and f are respectively circumferential and longitudinal singularity factor determined from a statistical study of all the temperatures measured for each can. The results are presented in about thirty tables and figures the most noteworthy results being summarized in the conclusion. (authors) [French] Les gaines a ailettes en chevron sont utilisees pour le refroidissement de l'uranium dans certains reacteurs nucleaires. Par chevron, on entend une disposition alternee des ailettes ayant un plan de symetrie parallele a la direction generale de l'ecoulement fluide. Les principaux parametres geometriques sont alors: le nombre des ailettes, le nombre de chevrons, l'angle d'inclinaison des ailettes par rapport a l'axe de la gaine, les dimensions des ailettes, le diametre de la gaine et le diametre du canal. L'etude est essentiellement

  2. Impedance de surface dans les supraconducteurs quasi-bidimensionnels

    Science.gov (United States)

    Achkir, Driss Brice

    Ce travail a caractere experimental et theorique vise l'etude de l'etat supraconducteur de trois familles de composes: les supraconducteurs conventionnels, les organiques et les cuprates YBCO. Pour ce faire, nous avons utilise une technique hyperfrequence, a savoir la mesure d'impedance de surface en fonction de la temperature et du champ magnetique. Dans les supraconducteurs conventionnels, nous avons mesure pour la premiere fois le pic de "coherence" dans la partie reelle de la conductivite. Bien que predit par la theorie BCS, ce pic n'avait pas ete clairement observe en raison de difficultes techniques liees a ce type d'experience. D'autre part, la theorie d'Eliashberg appliquee a la partie reelle de la conductivite du niobium nous a revele l'importance des mesures hyperfrequences pour mieux extraire la partie basse frequence de la densite spectrale alphasp2F(omega). Cette possibilite est attrayante puisque c'est precisement la region de frequences de alphasp2F(omega) ou les donnees d'effet tunnel sont imprecises. Les resultats obtenus sur la longueur de penetration dans les organiques et les cuprates ont permis de montrer que le gap presente des lignes de zeros au niveau de Fermi ou qu'il est, a tout le moins, fortement anisotrope. En effet, la dependance en temperature de la longueur de penetration dans les cristaux purs est lineaire a basse temperature et elle devient quadratique dans les cristaux dopes. Pour le cas des supraconducteurs organiques quasi-bidimensionnels (Et)sb2X, nous avons aussi observe un maximum sur la partie reelle de la conductivite qui n'a rien a voir avec un pic de coherence. Pour ces composes, nous avons effectue une des toutes premieres etudes des fluctuations supraconductrices en temperature et en champ magnetique. Nous montrons que la paraconductivite sigmasp' due aux fluctuations presente un comportement de type Aslamazov-Larkin de nature tridimensionnelle. Ces mesures sont appuyees par les resultats theoriques d'un modele Ginzburg

  3. 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)

  4. 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)

  5. Les figures multiples du maire.

    Directory of Open Access Journals (Sweden)

    Olivier Lebraud

    2004-06-01

    Full Text Available Alors même que l’ensemble du personnel gouvernemental et parlementaire est sujet à une relative désaffection de la part des citoyens, les maires français jouissent, on le sait, d’une popularité qui fait d’eux les figures centrales de la scène politique. Au-delà de la décentralisation, qui a souvent renforcé leur image de décideurs, ils ont su tirer parti de la dimension identitaire qui caractérise l’échelon communal pour devenir les acteurs indispensables de la vie locale. ...

  6. Les attaques des Termites (Isoptera) dans les parcelles de ...

    African Journals Online (AJOL)

    SARAH

    31 août 2016 ... habitations, les agro systèmes et les pâturages dans une savane sahélienne à Matam. (Sénégal). Mémoire de DEA, Université Ch. A. Diop de Dakar, pp. 51. Silvestri F : 1914-15. Contribuzione alla conoscenza dei. Termitidi e Termitophili dell'Africa occidentale. I. Termitidi. Bolletino del Laboratorio di ...

  7. Les changements climatiques et l'urbanisation menacent les ...

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

    5 sept. 2014 ... Cette perception correspond-elle aux données scientifiques ? Shah Alam Khan. Dans les quatre villes étudiées, on observe effectivement de réels changements dans les précipitations annuelles, mais pas nécessairement une diminution. À Gurgaon, il y aurait diminution selon l'opinion générale, ce qui ...

  8. Renforcer les partenariats entre les conseils subventionnaires de la ...

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

    Les conseils subventionnaires de la recherche scientifique sont essentiels au financement et à la promotion de la recherche et de l'innovation. Une récente étude de délimitation de la portée financée par le CRDI a souligné le rôle important qu'ils jouent dans les réseaux scientifiques nationaux en Afrique subsaharienne.

  9. Les chercheurs inquiets malgre les promesses de Claudie Haignere

    CERN Multimedia

    2003-01-01

    "Le 9 avril, lors d'un colloque sur l'innovation, la ministre deleguee a la recherche et aux nouvelles technologies a annonce, "en plein accord, dit-elle, avec le premier ministre", que "les etablissements publics a caractere scientifique et technologique (EPST) ne connaitront en 2003 aucune nouvelle annulation de credits de paiement et d'autorisations de programme" et que "les reserves de precaution sont entierement levees" (1 page).

  10. Les dyslipidemies et antiretroviraux chez les personnes vivant avec ...

    African Journals Online (AJOL)

    hypercholestérolémie, l'hyper LDL-cholestérolémie, l'hypo HDLcholestérolémie ont été retrouvées respectivement chez 41,4%, 23,5% et 17,4% des patients. La différence n'est pas significative entre les fréquences des troubles lipidiques chez les ...

  11. Les approches multisectorielles pour prévenir les grossesses ...

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

    Ce projet vise à générer, à travers une recherche opérationnelle, des connaissances sur le phénomène des grossesses précoces et de développer des stratégies multisectorielles, centrées sur les adolescents et prenant en compte les acteurs du système de l'éducation, de la santé, du milieu judiciaire et des communautés.

  12. LES VIBRIONS DANS LES PRODUITS DE LA PÊCHE

    African Journals Online (AJOL)

    PC_WINDOWS

    Santé Publique (ENSP) à Rennes et le Centre National de Référence des vibrions et du Choléra (CNRVC) à l'Institut Pasteur ... l'Alimentation, en France, dans le but de normaliser les protocoles d'étude et de recherche de V. cholerae et ..... Vibrio présente dans l'environnement avec les méthodes de détection habituelles.

  13. Les institutions sportives et les pouvoirs publics en Afrique noire ...

    African Journals Online (AJOL)

    La restitution plus fine des données archivées et leur analyse plus approfondie révèlent alors que : la réexportation des pratiques socioéducatives de l'école vers les clubs civils s'est plutôt arrimée aux enjeux économiques, politiques, diplomatiques et dans une moindre mesure éducatifs, tant et si bien que les acteurs ...

  14. Les representations sociales des musees par les jeunes de la ...

    African Journals Online (AJOL)

    La participation culturelle des jeunes reste un élément fondamental de la vie sociale. Ainsi, les musées sont des institutions culturelles qui contribuent à cette perspective. Mais, il est à constater que les visites muséales sont presque absentes des activités culturelles des jeunes. Le présent article propose une analyse des ...

  15. Association entre les hormones sexuelles, les marqueurs de ...

    African Journals Online (AJOL)

    Introduction: Le présent travail se propose d'étudier la relation entre les hormones sexuelles, notamment l'oestradiol et l'indice de l'oestradiol libre, le sulfate de déhydroépiandrosterone et la sex hormone binding globulin, les marqueurs de remodelage osseux et la densité minérale osseuse chez une population de ...

  16. The System for Controlling Source and Special Nuclear Material at the Eurochemic Reprocessing Plant; Systeme de Controle des Matieres Nucleaires Brutes et Speciales a l'Usine de Traitement D'Eurochemic; Sistema kontrolya nad iskhodnym i spetsial'nym yadernym materialom na zavode evrokhimicheskoj kompanii po regeneratsii yadernogo topliva; Control de Materiales Nucleares Basicos y de Materiales Fisionables Especiales en la Planta de Regeneracion de la Eurochemic

    Energy Technology Data Exchange (ETDEWEB)

    Frenzel, W.; Schueller, W. [EUROCHEMIC, MOL (Belgium)

    1966-02-15

    Eurochemic is constructing a reprocessing plant near Mol (Belgium). The main characteristics of the plant and the different process steps are summarized. To maintain proper control of source and special nuclear material, the facilities of the company are divided into material balance areas. All transfers into and out of these areas are determined. Depending on their significance for the overall material balance, different precision requirements have been established according to a scale of significance which is briefly discussed. To adjust the book balance, physical inventories are periodically performed. The corresponding inventory procedures are outlined. The books used for nuclear materials accounting and the principles of the accounting system are summarized. (author) [French] La societe Eurochemic fait actuellement construire une usine de traitement chimique pres de Mol (Belgique). L'auteur indique succinctement les principales caracteristiques de l'usine et les differentes etapes du traitement. Pour assurer un controle correct des matieres nucleaires brutes et speciales, les installations d'Eurochemic sont divisees en secteurs de mesures. Tous les transferts entre ces secteurs de mesure sont determines quantitativement. Les mesures sont faites avec des degres de precision differents qui ont ete fixes en fonction de leur importance pour le bilan matieres general; les auteurs examinent brievement les criteres appliques a cette fin. Pour verifier le bilan, on procede periodiquement a des inventaires materiels. La facon dont sont menes ces inventaires est exposee dans ses grandes lignes. Les auteurs indiquent les livres utilises pour la comptabilite des matieres nucleaires et resument les principes du systeme comptable. (author) [Spanish] La compania Eurochemic esta construyendo una planta de regeneracion en Mol (Belgica). Los autores resumen las principales caracteristicas de la instalacion, y las distintas fases del proceso industrial. Para mantener un control

  17. Study, with the help of nuclear indicators (HTO, Urea {sup 14}C and {sup 24}Na), of the renewal of water, urea and sodium in different parts of the rat kidney in aqueous diuresis and of the gerbil kidney in osmotic diuresis or in oliguria; Etude, a l'aide d'indicateurs nucleaires (HTO, UREE {sup 14}C et {sup 24}Na), du renouvellement de l'eau, de l'uree et du sodium dans les differentes regions du rein de rat en diurese aqueuse et de merion en diurese osmotique ou en oligurie

    Energy Technology Data Exchange (ETDEWEB)

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

    1965-06-01

    In the kidney of the gerbil in oliguria there exists a cortico-papillary gradient in the concentration of the sodium and of the urea; this gradient disappears in the gerbil kidney in osmotic diuresis or in the rat kidney in aqueous diuresis; in these three states of diuresis there is no significant difference in the potassium concentration between the surface and interior regions of the kidneys. Kinetic studies using tritiated water, urea {sup 14}C and {sup 24}Na show that water and urea in the interior regions of the kidney are only renewed very slowly (1 h) whereas the sodium is rapidly changed (1 mn). These results can be explained using WIRZ's theory concerning the mechanism of the counter-current concentration of urine. Furthermore, the evolution of the specific radioactivity of urea {sup 14}C is favorable for a cortical synthesis of urea. (author) [French] II existe dans le rein de Merions en oligurie un gradient cortico papillaire de la concentration du sodium et de l'uree; ce gradient est aboli dans le rein de Merions en diurese osmotique ou de rats en diurese aqueuse; dans ces 3 etats de diurese il n'y a pas de difference significative de la concentration du potassium entre les regions superficielles et profondes des reins. Des etudes cinetiques a l'aide d'eau tritiee, d'uree {sup 14}C et de {sup 24}Na montrent que l'eau et l'uree des regions profondes des reins ne sont renouveles que tres lentement (1 h), alors que le sodium est tres vite renouvele (1 mn). Ces resultats s'expliquent par la theorie de WIRZ sur le mecanisme de la concentration de l'urine par contre-courant. En outre, l'evolution renale de la radioactivite specifique de l'uree {sup 14}C est en faveur d'une synthese corticale de l'uree. (auteur)

  18. Les migrants de Beyrouth

    Directory of Open Access Journals (Sweden)

    Agnès Deboulet

    2009-03-01

    Full Text Available Depuis la fin de la guerre (1990 l’importation d‘une main-d’œuvre peu qualifiée majoritairement féminine est devenue massive au Liban. Qu’ils soient en situation régulière ou non, des migrants non arabes dits « temporaires » ou « en transit », mais dont certains sont là depuis une dizaine d’années, ont fait leur entrée sur le marché du travail et tentent de s’inscrire, pour nombre d’entre eux, dans un « milieu » aux identités multiples et conflictuelles dans des quartiers périphériques où il est plus facile de trouver à se loger. En s’appuyant sur des enquêtes de terrain menées dans la banlieue de Bourj-Hammoud à l’est de Beyrouth et dans les quartiers sud de Jnah et de Ouzaï, les auteures décrivent des situations migratoires qui sans être généralisables n’en sont pas moins exemplaires de la place de cette main-d’œuvre immigrée.Since the end of the war, in 1990, unqualified, mostly feminine, workers have been massively entering Lebanon. Whether they have regular registration or not, non-Arab, so-called ‘temporary’, or ‘transit’ migrants have entered the labour market, but some of them have been there for about ten years. Many try to join the mixed, full of conflicts environment of peripheral districts, in which it is easier to find housing. Using fieldwork they have been conducting in the Borj-Hamoud suburb, in the east of Beirut, and Jnah and Ouzaï, in the south, the authors describe migratory situations which, although they cannot be applied generally, are nevertheless a good example of the place held by these immigrant

  19. LES MALADIES NEUROLOGIQUES OBSERVEES EN ...

    African Journals Online (AJOL)

    LES MALADIES NEUROLOGIQUES OBSERVEES EN HOSPITALISATION, SUR UNE PERIODE DE 10 ANS DANS LA REGION DU DELTA AU NIGERIA NEUROLOGIC ADMISSIONS IN THE NIGER DELTA AREA OF NIGERIA – A TEN YEAR REVIEW (English)

  20. Les Miserables (2012) : Motion Picture

    OpenAIRE

    Lauri Lucente, Gloria; Buhagiar, Celaine

    2013-01-01

    Les Miserables : In 19th-century France, Jean Valjean, who for decades has been hunted by the ruthless policeman Javert after breaking parole, agrees to care for a factory worker's daughter. The decision changes their lives for ever.

  1. Advances in Electrochemical Models for Predicting the Cycling Performance of Traction Batteries: Experimental Study on Ni-MH and Simulation Développement de modèles électrochimiques de batteries de traction pour la prédiction de performances : étude expérimentale de batteries NiMH et simulations

    Directory of Open Access Journals (Sweden)

    Bernard J.

    2009-11-01

    Full Text Available Rigorous electrochemical models to simulate the cycling performance of batteries have been successfully developed and reported in the literature. They constitute a very promising approach for State-of-Charge (SoC estimation based on the physics of the cell with regards to other methods since SoC is an internal parameter of these physical models. However, the computational time needed to solve electrochemical battery models for online applications requires to develop a simplified physics-based battery model. In this work, our goal is to present and validate an advanced 0D-electrochemical model of a Ni-MH cell, as an example. This lumped-parameter model will be used to design an extended Kalman filter to predict the SoC of a Ni-MH pack. It is presented, followed by an extensive experimental study conducted on Ni-MH cells to better understand the mechanisms of physico-chemical phenomena occurring at both electrodes and support the model development. The last part of the paper focuses on the evaluation of the model with regards to experimental results obtained on Ni-MH sealed cells but also on the related commercial HEV battery pack. Des modèles électrochimiques fins permettant de simuler le comportement de batteries ont été développés avec succès et reportés dans la littérature. Ils constituent une alternative aux méthodes classiques pour estimer l’état de charge (SoC pour State of Charge des batteries, cette variable étant ici un paramètre interne du modèle physique. Cependant, pour les applications embarquées, il est nécessaire de développer des modèles simplifiés sur la base de ces modèles physiques afin de diminuer le temps de calcul nécessaire à la résolution des équations. Ici, nous présenterons à titre d’exemple un modèle électrochimique 0D avancé d’un accumulateur NiMH et sa validation. Ce modèle à paramètres concentrés sera utilisé pour réaliser un filtre de Kalman qui permettra la prédiction de l

  2. Les violences conjugales à Dakar

    Science.gov (United States)

    Soumah, Mohamed Maniboliot; Issa, Abdoul Wahab; Ndiaye, Mor; Ndoye, El Hadj Oumar; Sow, Mamadou Lamine

    2015-01-01

    L'objectif était d’évaluer les aspects épidémiologiques des violences conjugales, identifier les facteurs de risques et les différents types de violences conjugales, évaluer les conséquences des violences conjugales sur la santé des victimes, afin d'améliorer la prise en charge des victimes et la prévention du phénomène. Il s'est agit d'une étude transversale effectuée de décembre 2012 à janvier 2013 à Dakar. Les données ont été recueillies, après consentement, sur fiche d'enquête anonyme soumise à toute personne volontaire vivant en couple et résidant à Dakar. L'analyse statistique a été effectuée avec le logiciel SPSS 13.0. Le nombre de personnes victimes de violences conjugales était de 60 soit 37,30% dont 31 femmes (51,70%) et 29 hommes (48,30%). Le sex-ratio était de 0,93. Parmi les victimes, 53 étaient scolarisées soit 88,30%. Le régime matrimonial était de type monogame dans 39 cas (65%) et polygame dans 21 cas (35%). La vie en couple durait depuis moins de 11 ans dans 60% des cas et durait de 11 ans à 20 ans au plus dans 26,6% des cas. L’étude des types de violences montrait la fréquence des agressions physiques. Les armes utilisées étaient surtout les armes naturelles. Les principaux facteurs de risque de violence conjugale sont les facteurs sociodémographiques, culturels et économiques comme le jeune âge, l'inégalité du genre, les jeunes couples, la précarité, le niveau d'instruction élevé. La prise en charge des victimes et la prévention du phénomène restent insuffisantes dans nos pays. PMID:26918077

  3. The use radioactive tracers in the study of solid transport in water streams; Emploi de traceurs radioactifs pour l'etude du transport solide dans les cours d'eau

    Energy Technology Data Exchange (ETDEWEB)

    Courtois, G [Commissariat a l' Energie Atomique, Saclay (France).Centre d' Etudes Nucleaires; Jaffry, P; Heuzel, M [Laboratoire National d' Hydraulique de Chatou, 78 (France)

    1960-07-01

    The Laboratoire National d'Hydraulique which has been studying, during the last few years in conjunction with the Centre d'Etudes Nucleaires at Saclay, the development of apparatus and of methods of investigation of sediment transport by radioactive tracer techniques, is at the moment trying to perfect a genuinely quantitative method of investigation. Two experiments have recently been carried out in rivers, the first designed to investigate the transport of pebbles in the river Rhone, the other to investigate the movement of sands in the Niger. This second experiment has been supported by parallel experiments carried out on a reduced scale model of the Niger built at the laboratories of Chatou: in this experiment are used the radiation from {sup 56}Mn and {sup 24}Na obtained by direct activation of the crushed apricot store which represents, in the scale model, the natural sediment on the bed of the Niger. The combined efforts of the laboratories of Chatou and of the Centre d'Etudes Nucleaires at Saclay are at the moment directed to the application of radioactive tracers to studies on the scale models with the double aim: a) of having a single investigational method for the actual experiment and for the model making it possible to control the accuracy of the model in the preliminary stage of calibrating this model; b) of making the most of the possibilities of observation and of direct measurement offered by the scale models for studying the possibility of improving the tracer method, in particular with respect to the collecting of quantitative data. (author) [French] La Laboratoire National d'Hydraulique qui, depuis quelques annees a developpe, en collaboration avec le Centre d'Etudes Nucleaires de Saclay, les appareillages et les techniques d'etudes des mouvements de sediments par la methode des traceurs radioactifs, s'efforce actuellement de mettre au point un moyen d'investigation veritablement quantitatif. Deux experiences ont ete effectuees recemment en

  4. Le CRDI dans les Philippines

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

    Le CRDI appuie la recherche dans les. Philippines depuis 1972. Le travail qu'y ont accompli des universités et des instituts de recherche vigoureux et la participation active de la société civile ont entraîné d'importantes améliorations dans les domaines de l'agriculture, du suivi de la pauvreté et de la gestion des forêts.

  5. Comportements Sexuels parmi les Adolescents et Jeunes

    African Journals Online (AJOL)

    AJRH Managing Editor

    Cette étude a comme objectif spécifique d'analyser les prévalences des comportements sexuels à risque et leurs facteurs sociaux dans les pays francophones d'Afrique subsaharienne parmi les adolescents et jeunes, en mettant en exergue les diversités entre pays. Les données utilisées sont celles des Enquêtes ...

  6. Study of the first collective levels of the even-even nuclei between masses 182 and 206; Etude des premiers niveaux collectifs des noyaux pairs-pairs entre les masses 182 et 206

    Energy Technology Data Exchange (ETDEWEB)

    Barloutaud, R; Leveque, A; Lehmann, P; Quidort, J [Commissariat a l' Energie Atomique, Saclay (France).Centre d' Etudes Nucleaires

    1959-07-01

    The reduced probabilities of deexcitation of the first two 2 + levels of {sup 184}W, {sup 186}W, {sup 188}Os, {sup 190}Os, {sup 192}Os and {sup 194}Pt have been deduced from coulombic excitation experiments on these nuclei.The results are included in a chart of the properties of the first two 2 + levels of even-even nuclei situated between masses 182 and 206. The variation of these properties as a function of nuclear distortion is compared with the various theoretical predictions concerning vibration levels. (author) [French] Les probabilites reduites de desexcitation des deux premiers niveaux 2 + de {sup 184}W, {sup 186}W, {sup 188}Os, {sup 190}Os, {sup 192}Os and {sup 194}Pt ont ete deduites des experiences d'excitation coulombienne de ces noyaux. Les resultats sont inseres dans une systematique des proprietes des deux premiers niveaux 2 + des noyaux pairs-pairs situes entre les masses 182 et 206. La variation de ces proprietes en fonction de la deformation nucleaire est comparee aux diverses predictions theoriques concernant les niveaux de vibration. (auteur)

  7. Winter School Les Houches

    CERN Document Server

    Lannoo, Michel; Bastard, Gérald; Voos, Michel; Boccara, Nino

    1986-01-01

    The Winter School held in Les Houches on March 12-21, 1985 was devoted to Semiconductor Heterojunctions and Superlattices, a topic which is recognized as being now one of the most interesting and active fields in semiconductor physics. In fact, following the pioneering work of Esaki and Tsu in 1970, the study of these two-dimensional semiconductor heterostructures has developed rapidly, both from the point of view of basic physics and of applications. For instance, modulation-doped heterojunctions are nowadays currently used to investigate the quantum Hall effect and to make very fast transistors. This book contains the lectures presented at this Winter School, showing in particular that many aspects of semiconductor heterojunctions and super­ lattices were treated, extending from the fabrication of these two-dimensional systems to their basic properties and applications in micro-and opto-electron­ ics. Among the subjects which were covered, one can quote as examples: molecular beam epitaxy and metallorgani...

  8. Emprego da submucosa de intestino delgado porcina no reparo de lesões do esôfago cervical. Estudo experimental em cães Small intestine submucosa for repair of cervical esophageal lesions in a dog model

    Directory of Open Access Journals (Sweden)

    Zacarias Alves de Souza Filho

    2003-06-01

    Full Text Available OBJETIVO: Pesquisar a eficácia da submucosa de intestino delgado (SID porcina como enxerto para reparo de lesões em esôfago cervical de cães. MÉTODOS: Foram operados 10 cães. Ressecou-se parcialmente uma porção da parede anterior do esôfago que foi substituída por um enxerto de SID. Avaliaram-se a resistência tensiométrica, o aspecto macroscópico, a regeneração tecidual e a concentração de colágeno da porção esofágica onde se implantou o enxerto. RESULTADOS: Não houve infecção, fístula ou estenose. Verificou-se ganho semelhante de resistência do esôfago operado em relação ao controle: 31.84N contra 28.60N em média (p=0,593. A macroscopia revelou cicatrização completa com pouca retração tecidual. O estudo anátomo-patológico por HE mostrou re-epitelização completa da mucosa, proliferação vascular discreta a moderada e proliferação fibroblástica intensa. Na análise do colágeno pelo Sirus-red obteve-se em média 54.04% de colágeno tipo I, 16,04% de colágeno tipo III e 71.58% de colágeno total. CONCLUSÃO: A SID mostrou ser, no cão, um enxerto eficaz no reparo de lesões maiores do esôfago, apresentando-se resistente à infecção e à rejeição. A SID deve ser, portanto, considerada opção importante no tratamento destas lesões.PURPOSE: Study of porcine small intestinal submucosa (SIS efficiency as a graft in the handling of lesions of the cervical esophagus in dogs. METHODS: Ten dogs were operated. A resection of a portion of the anterior wall of the esophagus was performed, followed by its repair with a SIS graft. The tensiometric resistance, macroscopic appearance regeneration process and collagen contents of the esophagus tissue were evaluated. RESULTS: No cases of fistula, stenosis or infection occured. Tensiometric evaluation showed a similar resistance in the operated esophagus when compared to the control (an average of 31.84N against 28.60N. Macroscopic analysis revealed complete healing

  9. Controverses sur les sucres [Controversies about sugars

    Directory of Open Access Journals (Sweden)

    Malika BOUCHENAK

    2016-12-01

    Full Text Available La surconsommation de sucres ajoutés et leurs effets putatifs sur diverses pathologies cardiométaboliques continuent de susciter des controverses. Dans les années 1950, le taux élevé de maladies cardiovasculaires (MCV, chez les hommes Américains a conduit à des études sur le rôle des facteurs alimentaires, tels que le cholestérol, les phytostérols, l'excès de calories, les acides aminés, les graisses, les glucides, les vitamines et les minéraux, à influencer le risque de MCV. Dans les années 60, deux éminents physiologistes, plaidant pour des hypothèses causales divergentes de MCV, John Yudkin a identifié les sucres ajoutés comme agent primaire, tandis que Ancel Keys identifiait les graisses totales, les graisses saturées et le cholestérol alimentaire. Cependant, dans les années 80, peu de scientifiques croyaient que les sucres ajoutés jouaient un rôle important dans la maladie coronarienne, et les premiers conseils nutritionnels de 1980 (1980 Dietary Guidelines for americans étaient axés sur la réduction des graisses totales, des graisses saturées et du cholestérol alimentaire pour la prévention des MCV.

  10. Les brulures electriques chez les voleurs de cuivre

    Science.gov (United States)

    Belmir, R.; Fejjal, N.; Achbouk, H.; El Mazouz, S.; Gharib, N.; Abassi, A.; Belmahi, A.

    2011-01-01

    Summary Les vols de biens fabriqués avec le cuivre semblent en hausse depuis un certain temps du fait de son prix élevé de revente, ce qui est à l’origine d’une augmentation du nombre d’accidents électriques par haut voltage (AEHV) qui sont graves du fait des brûlures profondes qu’elles provoquent le long des axes vasculo-nerveux. Les Auteurs rapportent une série de neuf cas d’AEHV traités au service de chirurgie plastique et de brûlés de l’Hôpital Ibn Sina de Rabat, Maroc, à travers laquelle ils étudient les caractéristiques épidémiologiques, cliniques et thérapeutiques. La population intéressée était jeune et active. Les brûlures étaient secondaires à un contact avec des câbles à haute tension lors de tentatives de vol par arrachement de conducteurs en cuivre dans les transformateurs dans 67% des cas, et lors de tentatives de coupure de caténaires alimentant les trains électriques sur le réseau ferroviaire dans 33% des cas. Le traitement des lésions électrothermiques a nécessité des interventions itératives avec amputation et désarticulation des segments de membres nécrosés dans 66% des cas, dont les suites étaient marquées par des séquelles fonctionnelles invalidantes. La prévention de ce type d’AEHV reste fondamentale. PMID:22262961

  11. Study, with the help of nuclear indicators (HTO, Urea {sup 14}C and {sup 24}Na), of the renewal of water, urea and sodium in different parts of the rat kidney in aqueous diuresis and of the gerbil kidney in osmotic diuresis or in oliguria; Etude, a l'aide d'indicateurs nucleaires (HTO, UREE {sup 14}C et {sup 24}Na), du renouvellement de l'eau, de l'uree et du sodium dans les differentes regions du rein de rat en diurese aqueuse et de merion en diurese osmotique ou en oligurie

    Energy Technology Data Exchange (ETDEWEB)

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

    1965-06-01

    In the kidney of the gerbil in oliguria there exists a cortico-papillary gradient in the concentration of the sodium and of the urea; this gradient disappears in the gerbil kidney in osmotic diuresis or in the rat kidney in aqueous diuresis; in these three states of diuresis there is no significant difference in the potassium concentration between the surface and interior regions of the kidneys. Kinetic studies using tritiated water, urea {sup 14}C and {sup 24}Na show that water and urea in the interior regions of the kidney are only renewed very slowly (1 h) whereas the sodium is rapidly changed (1 mn). These results can be explained using WIRZ's theory concerning the mechanism of the counter-current concentration of urine. Furthermore, the evolution of the specific radioactivity of urea {sup 14}C is favorable for a cortical synthesis of urea. (author) [French] II existe dans le rein de Merions en oligurie un gradient cortico papillaire de la concentration du sodium et de l'uree; ce gradient est aboli dans le rein de Merions en diurese osmotique ou de rats en diurese aqueuse; dans ces 3 etats de diurese il n'y a pas de difference significative de la concentration du potassium entre les regions superficielles et profondes des reins. Des etudes cinetiques a l'aide d'eau tritiee, d'uree {sup 14}C et de {sup 24}Na montrent que l'eau et l'uree des regions profondes des reins ne sont renouveles que tres lentement (1 h), alors que le sodium est tres vite renouvele (1 mn). Ces resultats s'expliquent par la theorie de WIRZ sur le mecanisme de la concentration de l'urine par contre-courant. En outre, l'evolution renale de la radioactivite specifique de l'uree {sup 14}C est en faveur d'une synthese corticale de l'uree. (auteur)

  12. Les gens, et non les choses, calment les eaux de la lagune de Tam ...

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

    Cathy Egan

    La lagune de Tam Giang au Viet Nam est un habitat naturel presque parfait pour la pêche et l'aquaculture. Longue de plus de 70 km et d'une profondeur moyenne d'à peine deux mètres, la lagune est un milieu des plus productifs, tant pour les espèces d'eau douce que pour les espèces marines. Au cours des dernières ...

  13. Les institutions de recherche sur les politiques et les ODD liés à la ...

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

    Le nouveau site Web facilitera l'enregistrement des événements démographiques afin d'améliorer l'accès aux services pour tous. Le nouveau site Web et la nouvelle bibliothèque de ressources aideront à améliorer les systèmes d'information et d'enregistrement des faits d'état civil dans les pays en développement.

  14. Les adjectifs à valeur intensive dans les groupes nominaux

    Directory of Open Access Journals (Sweden)

    Buvet Pierre-André

    2012-07-01

    Full Text Available Un dictionnaire électronique est élaboré dans la perspective du Traitement Automatique des Langues. Il s'agit d'une ressource qui est exploité par un ensemble d'outils informatiques pour donner lieu à une application dédiée au traitement de l'information textuelle. Le dictionnaire électronique présenté dans l'article concerne principalement des adjectifs prédicatifs à forme simple qui ont fait l’objet d’un recensement exhaustif et qui ont été décrits formellement. Sa macrostructure est constituée de plus de 20 000 emplois adjectivaux. Sa microstructure comporte des descripteurs normalisés de telle sorte que les informations métalinguistiques stipulées permettent d'effectuer des analyses sémantiques fines. Les adjectifs prédicatifs à forme complexe sont également incorporés au dictionnaire; ils sont décrits comme les adjectifs prédicatifs à forme simple dans la mesure où ils fonctionnent de la même façon. Dans un premier temps, nous discutons de la notion d'adjectif prédicatif en précisant préalablement les notions de prédicat et d'emploi prédicatif ainsi que celles de signification lexicale et de signification grammaticale. Nous présentons les marqueurs de l’intensité qui correspondent à des adjectifs monolexicaux et prédicatifs ou bien polylexicaux et prédicatifs. Nous discutons de ces adjectifs dans un premier temps selon qu’il s’agit de modifieurs libres, dans un deuxième temps de modifieurs liés et dans un troisième temps de constituants d’une détermination figée. Nous précisons dans les trois cas de figure quelles sont les conditions d’occurrences des adjectifs prédicatifs dans les groupes nominaux en nous appuyant sur les descriptions des adjectifs et des déterminants du français qui proviennent de deux bases de données exhaustives.

  15. Réduire les risques et les pertes attribuables aux changements ...

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

    22 août 2014 ... Entre-temps, dans les pays plus riches, comme le Japon et les États‑Unis, les bâtiments et l'infrastructure font l'objet de nouvelles conceptions visant à prévenir les conséquences des tremblements de terre. Quelle comparaison feriez‑vous entre les plans d'adaptation aux tremblements de terre et les ...

  16. Les changements climatiques brouillent les prédictions des faiseurs ...

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

    8 oct. 2010 ... Depuis des générations, les autochtones de l'ouest du Kenya comptent sur les pouvoirs mystiques que possèdent les « faiseurs de pluie » du clan Nganyi pour prédire la météo. Cependant, le temps instable amené par les changements climatiques brouille les indices grâce auxquels les faiseurs de pluie ...

  17. Understanding the corrosion phenomena to organize the nondestructive evaluation programs in the nuclear power plants; Connaitre les phenomenes de corrosion pour organiser les programmes d'end dans les centrales nucleaires

    Energy Technology Data Exchange (ETDEWEB)

    Berge, J.Ph. [Federation Europeenne de Corrosion, 75 - Paris (France); Samman, J. [Electricite de France (EDF), Div. du Production Nucleaire, 75 - Paris (France)

    2001-07-01

    The french nuclear power plants used PWR which components revealed many corrosion defects of different shapes as stress corrosion cracks or pits. Understanding the corrosion processes will help the inspection of in service power plants. The following examples describe some corrosion cases and present the corresponding developed control methods: corrosion on condenser, secondary circuit pipes and corrosion-erosion, steam generator pipes, vessels head penetration. (A.L.B.)

  18. Contribution to the study and use of ionisation chambers for nuclear reactor control (1965); Contribution a l'etude et a l'utilisation des chambres d'ionisation pour le controle des reacteurs nucleaires (1965)

    Energy Technology Data Exchange (ETDEWEB)

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

    1961-02-15

    high-power reactors. (author) [French] Les chambres d'ionisation sont actuellement les detecteurs les mieux adaptes au controle des reacteurs nucleaires par des mesures neutroniques. Nous avons cru bon de rappeler quelques generalites concernant la dynamique des reacteurs, les differents procedes de detection des neutrons, le fonctionnement des chambres d'ionisation et les methodes de mesure utilisees. Notre contribution aux techniques de controle des reacteurs consiste d'une part en une tentative de synthese des facteurs intervenant dans le fonctionnement des chambres d'ionisation, l'etude de ces facteurs, et d'autre part l'elaboration de chambres d'ionisation a fission et a bore permettant de suivre la marche d'un reacteur du demarrage jusqu'a la puissance maximale. Dans le domaine des chambres a fission, nous avons en particulier ameliore les techniques de depot d'oxyde d'uranium sur l'aluminium et realise la mise au point de depots par electrolyse sur d'autres metaux: acier inoxydable, cuivre, molybdene, nickel, tantale, titane, kovar, tungstene et beryllium. Nous avons elabore plusieurs types de chambres a fission servant au demarrage des reacteurs: un type de performances moyennes actuellement utilise dans les piles francaises un type a haute sensibilite un type a haute temperature qui a fonctionne jusqu'a 600 deg. C. En ce qui concerne les chambres a bore, nous avons etudie les perturbations apportees dans les mesures par l'exposition des chambres a d'importants flux de neutrons et a un rayonnement {gamma} intense. Cette exposition produit une modification des proprietes des materiaux constitutifs et la production dans les chambres d'un bruit de fond qui peut gener considerablement les mesures neutroniques. Nous avons montre que la technique de compensation permettait de limiter l'importance de ce bruit de fond et d'augmenter ainsi la plage de fonctionnement des chambres d'ionisation classiques destinees aux mesures de puissance. Enfin, nous avons realise deux

  19. Diffuse Scattering from Alloys and Disordered Systems: Experimental Techniques and Potentialities; Diffusion dans les Alliages et les Systemes Desordonnes; Methodes Experimentales et Possibilites d'Application; Diffuznoe rasseyanie na splavakh i razuporyadochennykh sistemakh. ehksperimental'nye metody i potentsial'nye vozmozhnosti; Dispersion Difusa en Aleaciones y Sistemas Desordenados; Tecnicas Experimentales y Posibilidades

    Energy Technology Data Exchange (ETDEWEB)

    Low, G. G. [Atomic Energy Research Establishment, Harwell, Berks (United Kingdom)

    1965-04-15

    field. Included among the latter are measurements of the diffuse magnetic scattering from paramagnetic salts. Observations of such scattering are of great interest since they contain direct information on the amount of spin transferred as a result of covalency, from a magnetic ion on to the ligands which surround it. (author) [French] Le memoire a pour objet d'examiner, du point de vue des principes et de la pratique, les divers renseignements que l'on peut obtenir en etudiant la diffusion elastique des neutrons. L'auteur traite surtout des systemes comportant une disposition stochastique des defauts, au sujet desquels on peut supposer qu'aucun n'est affecte par la presence des autres, soit en raison de la dilution, soit en raison d'une independance intrinseque 1 l'egard de l'environnement. Dans ces conditions, l'intensite diffusee est proportionnelle au carre du module d'une transformee de Fourier sur la perturbation de l'amplitude de diffusion associee a un defaut. On peut ainsi obtenir des renseignements sur la distribution spatiale de cette amplitude de diffusion en procedant aux mesures appropriees de diffusion des neutrons et en operant une inversion de Fourier. En pratique, vu le grand nombre de phenomenes qui contribuent au bruit de fond de diffusion, on n'a pu jusqu'a present faire des mesures que pour un petit nombre de champs. On a notamment realise des progres considerables en ce qui concerne les defauts magnetiques dans les ferro-aimants ou l'on peut faire varier la section efficace magnetique en modifiant la direction de magnetisation par rapport au vecteur de diffusion des neutrons. Cto parvient ainsi a separer la diffusion consideree des effets non magnetiques sous la forme d'une difference entre les deux mesures d'intensite. Un phenomene qui contribue au bruit de fond de diffusion et qui possede un caractere partiellement magnetique et par consequent n'est pas elimine par la technique susmentionnee, est la diffusion multiple de Bragg dans un polycristal

  20. ["Les Impatients": expression through art].

    Science.gov (United States)

    Lamontagne, Céline; Palardy, Lorraine

    2015-01-01

    The organization called "Les Impatients" was founded in 1992. Using a unique model, Les Impatients welcomes those with mental health issues who would like to express themselves through art. Les Impatients offers free creative workshops and encourages exchanges with the community through the sharing of its participants' creations. The name Les Impatients reinforces the idea that the organization does not consider those attending its workshops as patients, but rather creators who are eager to heal, develop their craft and find their place in society. The participants contribute to the collective objective of breaking down the stigma that surrounds mental illness.Les Impatients collaborates with various mental health organizations in Quebec, such as the Institut universitaire en santé mentale de Montréal (IUSMM) affiliated to the Université de Montréal, Douglas Mental Health University Institute (DMHUI), the Centre de santé et services sociaux Drummond (CSSS Drummond) and the Centre de santé et services sociaux Pierre-Boucher (CSSS Pierre-Boucher). Les Impatients offers more than 48 workshops in eight different locations to around 450 participants each week.Dissemination activities, remarkable events, original projects: Les Impatients stands out through its realizations. Examples are exhibitions, collections of love letters, comic books, CD, concerts, and reading nights. The organization's originality resides in the exploration of the links between the work of the participants and that of professional artists. An illustration of this interest is the annual Parle-moi d'amour auction-exhibition, which has been one of Les Impatients' major events since 1999.As part of its mission, Les Impatients conserves the works of art created by the participants during the workshops. Its collection includes more than 15,000 works of art from Les Impatients as well as pieces donated by collectors of unconventional art, commonly known as "art brut" or "outsider art". The

  1. Max Planck et les quanta

    CERN Document Server

    Boudenot, Jean-Claude

    2016-01-01

    « Les atomes, dit Jean Perrin en 1913, ne sont pas ces éléments éternels et insécables dont l'irréductible simplicité donnait au possible une borne, et, dans leur inimaginable petitesse, nous commençons à pressentir un fourmillement prodigieux de mondes nouveaux ». C'est bien dans un monde totalement nouveau, le monde quantique, que nous a fait pénétrer la découverte des quanta par Max Planck. Son article de 1900 est le déclencheur de l'une des plus grandes révolutions scientifiques de tous les temps. Les trente années qui suivent sont les plus riches de la physique ; Planck, Einstein, Bohr, Sommerfeld, de Broglie, Schrödinger, Heisenberg, Dirac, Born, Pauli… reconstruisent la physique sur de nouvelles bases sur fond de conflit des générations. Le monde est par ailleurs secoué par la guerre, Max Planck est tourmenté et vit des épreuves personnelles dramatiques. C'est l'homme, aussi bien que l'oeuvre, que les auteurs ont tenté de dépeindre dans cet ouvrage. Ils ont également souhait�...

  2. Use of 14 MeV neutrons in activation analysis. Experiments carried out at the Grenoble nuclear research Centre (1963); Utilisation de neutrons de 14 MeV en analyse par activation. Experience realisee au Centre d'etudes nucleaires de Grenoble (1963)

    Energy Technology Data Exchange (ETDEWEB)

    Auboin, G; Guazzoni, P; Laverlochere, J [Commisariat a l' Energie Atomique, Grenoble (France). Centre d' Etudes Nucleaires

    1963-07-01

    The use of 14 MeV neutron irradiation makes it possible to extend the field of application of activation analysis to elements which cannot be activated in nuclear reactors (oxygen, boron, for example) or else to consider the possibility of 'portable' measurement units for routine analyses. With this aim, tests have been carried out for studying the sensitivity and interferences in the case of the dosing of oxygen in eleven different matrices using 150 and 300 kV SAMES accelerators producing 14 MeV neutrons by the reaction {sup 3}H (d, n) {sup 4}He. The sensitivity of the dosage methods for six writer elements has also been studied. The results obtained show that, for a neutron flux of 10{sup 10} n/4{pi}, the sensitivities vary from 100 {mu}g and 1 mg for oxygen in nine matrices (Be, Ta, Nb, Ti, Zr, Fe, Al, Sb, Si) and that it is possible to dose the six elements F, B, Y, Si, N, Al with sensitivities of between 1 an 1000 micrograms. (authors) [French] L'irradiation au moyen de neutrons de 14 MeV permet d'etendre le domaine d'application de l'analyse par activation a des elements non activables en reacteur nucleaire (oxygene, bore, par exemple) ou encore d'envisager des unites de dosage ''portables'' pour des analyses de routine. Dans ce but, des essais ont ete effectues pour etudier les sensibilites et les interferences dans le cas du dosage de l'oxygene dans onze matrices differentes, au moyen d'accelerateurs SAMES 150 et 300 kV. produisant les neutrons de 14 MeV par la reaction {sup 3}H (d, n) {sup 4}He. Des sensibilites de dosage ont egalement ete etudiees pour six autres elements. Les resultats obtenus montrent que, pour un flux de neutrons de 10{sup 10} n /4{pi}, les sensibilites varient entre 100 {mu}g et 1 mg, pour l'oxygene dans neuf matrices (Be, Ta, Nb, Ti, Zr, Fe, Al, Sb, Si) et qu'il est possible de doser les six elements F, B, Y, Si, N, Al avec des sensibilites se situant entre 1 et 1000 microgrammes. (auteurs)

  3. Avis 4 sur les nanosciences et les nanotechnologies

    OpenAIRE

    Centre de Coopération Internationale en Recherche Agronomique pour le Développement

    2012-01-01

    À l'échelle nanométrique, l’imbrication entre savoirs et savoir-faire est telle que la distinction entre nanosciences et nanotechnologies devient artificielle, le Comité entendant à travers les “nanotechnologies” la profonde continuité qui prévaut au sein des sciences fondamentales et des technologies.[br/] Le Comité a dressé un panorama des applications avérées et potentielles des nanotechnologies dans le domaine de l’agriculture et de l’alimentation, y compris dans les pays du Sud, tou...

  4. Fission Data and Nuclear Technology; Constantes de Fission et Technologie NucleAire; 0414 0410 041d 041d 042b 0415 . 041e 0414 0415 041b 0415 041d 0418 0418 0418 042f 0414 0415 0420 041d 0410 042f 0422 0415 0425 041d 041e 041b 041e 0413 0418 042f ; Datos Sobre la Fision y Tecnologia Nuclear

    Energy Technology Data Exchange (ETDEWEB)

    Hanna, G. C. [Chalk River Nuclear Laboratories, Chalk River, ON (Canada)

    1965-07-15

    Accurate nuclear data for fissile nuclei are required not only by reactor designers, but also by reactor physicists for the interpretation of integral experiments, e.g. studies of the change of reactivity with irradiation. Some of the requests that have been made for such fission data, and the reasons behind them, are discussed, along with the progress that has been made towards their fulfilment. An attempt is made to outline those areas where better data are required. (author) [French] On a besoin de valeurs exactes des constantes nucleaires concernant les noyaux fissiles, non seulement pour les etudes de reacteurs, mais egalement pour la physique des reacteurs lorsqu'on veut interpreter les experiences integrales, c'est-a-dire dans les etudes sur les modifications de la reactivite avec l'irradiation. L'auteur discute certaines des demandes de renseignements sur les constantes de fission, les raisons pour lesquelles elles ont ete faites et la mesure dans laquelle elles ont pu etre satisfaites. Il s'efforce egalement de delimiter les domaines dans lesquels on aurait besoin de valeurs plus precises. (author) [Spanish] No solo quienes trabajan.en el proyecto de reactores requieren datos nucleares exactos sobre los nucleos fisionables, sino que tambien los fisicos de reactores los necesitan para interpretar los resultados de experimentos integrales, como por ejemplo, en los estudios sobre la variacion de la reactividad en funcion de la irradiacion. El autor describe algunas de las peticiories de datos de esa clase que se han formulado, asi como los adelantos realizados con objeto de satisfacerlas. Tambien indica, en lineas generales, aiquellas esferas en las que se necesitan datos mas amplios y exactos. (author) [Russian] Tochnye jadernye dannye o rasshhepljajushhihsja jadrah neobhodimy ne tol'ko konstruktoram reaktorov, no takzhe i fizikam-reak- torshhikam dlja interpretacii integral'nyh jeksperimentov, to est' dlja izuchenija izmenenija reaktivnosti po mere

  5. Contribution to the study of nuclear fuel materials with a metallic uranium base; Contribution a l'etude des materiaux combustibles nucleaires a base d'uranium metallique

    Energy Technology Data Exchange (ETDEWEB)

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

    1957-11-15

    In a power reactor destined to supply industrially recoverable thermal energy, the most economical source of heat still consists of natural metallic uranium. However, the nuclear fuel material, most often employed in the form of rods of 20 to 40 mm diameter, is subjected to a series of stresses which lead to irreversible distortions usually incompatible with the substructure of the reactor. As a result the fuel material must possess at the outset a certain number of qualities which must be determined. Investigations have therefore been carried out, first on the technological characters peculiar to each of the three allotropic phases of pure uranium metal, and on their interactions on the stabilisation of the material which consists of either cast uranium or uranium pile-treated in the {gamma} phase. (author) [French] Dans un reacteur de puissance destine a fournir de l'energie thermique industriellement recuperable, la source de chaleur la plus economique reste constituee par de l'uranium metallique naturel. Or, le materiau combustible nucleaire, employe le plus souvent sous forme de barreaux de 20 a 40 mm de diametre, se trouve soumis a un ensemble de contraintes qui provoque des deformations irreversibles, le plus souvent incompatibles avec l'infrastructure du reacteur. Par consequent, le materiau combustible doit presenter a l'origine un certain nombre de qualites qu'il est necessaire de determiner. Aussi a-t-on d'abord etudie les caracteres technologiques propres a chacune des trois phases allotropiques de l'uranium-metal pur et leurs interactions sur la stabilisation du materiau constitue soit par de l'uranium coule, soit par de l'uranium traite en pile en phase {gamma}. (auteur)

  6. Development of a power-period calculation unit for nuclear reactor Control; Etude et realisation d'un ensemble de calcul puissance periode pour le controle d'un reacteur nucleaire

    Energy Technology Data Exchange (ETDEWEB)

    Martin, J [Commissariat a l' Energie Atomique, Centre d' Etudes Nucleaires de Saclay, 91 - Gif-sur-Yvette (France)

    1966-10-01

    The apparatus studied is a digital calculating assembly which makes it possible to prepare and to present numerically the period and power of a nuclear reactor during operation, from start-up to nominal power. The pulses from a fission chamber are analyzed continuously, using real time. A small number of elements is required because of the systematic use of a calculation technique comprising the determination of a base 2 logarithm by a linear approximation. The accuracy obtained for the period is of the order of 14%; the response time of the order of the calculated period value. An approximate value of the power (30%) is given at each calculation cycle together with the power thresholds required for the control. (author) [French] L'appareil etudie est un ensemble de calcul digital permettant d'elaborer et d'afficher numeriquement la periode et la puissance, d'un reacteur nucleaire lors de son fonctionnement depuis le demarrage jusqu'a la puissance nominale. Il traite en temps reel, de facon continue, les impulsions en provenance d'une chambre de fission. Grace a l'utilisation systematique d'une technique de calcul, la determination d'un logarithme a base 2 par approximation lineaire, un nombre reduit d'elements est utilise. La precision obtenue sur la periode est de l'ordre de 14 pour cent, le temps de reponse de l'ordre de la valeur de la periode calculee. Un ordre de grandeur de la puissance (30 pour cent) est donne a chaque cycle de calcul ainsi que des seuils de puissance necessaires au controle. (auteur)

  7. DONNEES PRELIMINAIRES SUR LES HABITUDES ...

    African Journals Online (AJOL)

    Administrateur

    Le régime alimentaire des chauves-souris paillées, Eidolon helvum (Kerr, 1792) de la commune du Plateau à Abidjan, Côte d'Ivoire a été étudié d'août 2007 à juillet 2008, en vue de connaître sa composition et de déterminer la préférence alimentaire de ces animaux, ainsi que les variations saisonnières. Les résultats.

  8. Detection and location of can rupture in reactors cooled by a flow of water; Detection et localisation des ruptures de gaines sur les reacteurs refroidis par circulation d'eau

    Energy Technology Data Exchange (ETDEWEB)

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

    1968-07-01

    This report brings together the principal methods of fission-product detection used for water reactors. The position, type and method of adjustment is given for each detector. The methods for localizing the defective elements are explained, in particular those using water sampling or decreases in the flux. A few installations are briefly described. They correspond to particular types of reactors using boiling, pressurized or cold water. Amongst the many methods used, it can be noted that when the fuel is resistant, the installations are fairly compact. In nuclear super-heated reactors on the other hand, the study of fuel behaviour calls for larger installations. An identification of defective elements exists when the reactor structure allows it. If this is not possible, a localization in a group of elements is obtained by a flux depression. (author) [French] Ce rapport rassemble les principales methodes de detection de produits de fission utilisees pour des reacteurs a eau. On indique pour les detecteurs leurs emplacements, leurs types, leurs reglages. On explique quelles sont les methodes de localisation des elements defectueux, en particulier celles utilisant des prelevements d'eau ou des depressions de flux. Quelques installations sont decrites sommairement. Elles correspondent a des types particuliers de reacteurs a eau bouillante, pressurisee ou froide. Parmi les nombreuses methodes utilisees, on constate que les installations sont peu importantes, lorsque le combustible est resistant. Par contre dans les reacteurs a surchauffe nucleaire l'etude du comportement du combustible necessite des installations plus importantes. Une identification d'elements defectueux existe lorsque la structure du reacteur le permet. A defaut une localisation dans un groupe d'elements est obtenue par depression de flux. (auteur)

  9. Boundary layers affected by different pressure gradients investigated computationally by a zonal RANS-LES method

    International Nuclear Information System (INIS)

    Roidl, B.; Meinke, M.; Schröder, W.

    2014-01-01

    Highlights: • Reformulated synthetic turbulence generation method (RSTGM) is applied. • Zonal RANS-LES method is applied to boundary layers at pressure gradients. • Good agreement with the pure LES and other reference data is obtained. • The RSTGM is applicable to pressure gradient flows without modification. • RANS-to-LES boundary should be located where -1·10 6 6 is satisfied. -- Abstract: The reformulated synthetic turbulence generation (RSTG) method is used to compute by a fully coupled zonal RANS-LES approach turbulent non-zero-pressure gradient boundary layers. The quality of the RSTG method, which is based on the same shape functions and length scale distributions as in zero-pressure gradient flow, is discussed by comparing the zonal RANS-LES findings with pure LES, pure RANS, direct numerical simulation (DNS), and experimental data. For the favorable pressure gradient (FPG) simulation the RANS-to-LES transition occurs in the accelerated flow region and for the adverse pressure gradient (APG) case it is located in the decelerated flow region. The results of the time and spanwise averaged skin-friction distributions, velocity profiles, and Reynolds stress distributions of the zonal RANS-LES simulation show a satisfactory to good agreement with the pure LES, reference DNS, and experimental data. The quality of the findings shows that the rigorous formulation of the synthetic turbulence generation makes the RSTG method applicable without a priori knowledge of the flow properties but those determined by the RANS solution and without using additional control planes to regulate the shear stress budget to a wide range of Reynolds numbers and pressure gradients. The method is a promising approach to formulate embedded RANS-to-LES boundaries in flow regions where the Pohlhausen or acceleration parameter satisfies -1·10 -6 ⩽K⩽2·10 -6

  10. Towards LES Models of Jets and Plumes

    Science.gov (United States)

    Webb, A. T.; Mansour, N. N.

    2000-01-01

    As pointed out by Rodi standard integral solutions for jets and plumes developed for discharge into infinite, quiescent ambient are difficult to extend to complex situations, particularly in the presence of boundaries such as the sea floor or ocean surface. In such cases the assumption of similarity breaks down and it is impossible to find a suitable entrainment coefficient. The models are also incapable of describing any but the most slowly varying unsteady motions. There is therefore a need for full time-dependent modeling of the flow field for which there are three main approaches: (1) Reynolds averaged numerical simulation (RANS), (2) large eddy simulation (LES), and (3) direct numerical simulation (DNS). Rodi applied RANS modeling to both jets and plumes with considerable success, the test being a match with experimental data for time-averaged velocity and temperature profiles as well as turbulent kinetic energy and rms axial turbulent velocity fluctuations. This model still relies on empirical constants, some eleven in the case of the buoyant jet, and so would not be applicable to a partly laminar plume, may have limited use in the presence of boundaries, and would also be unsuitable if one is after details of the unsteady component of the flow (the turbulent eddies). At the other end of the scale DNS modeling includes all motions down to the viscous scales. Boersma et al. have built such a model for the non-buoyant case which also compares well with measured data for mean and turbulent velocity components. The model demonstrates its versatility by application to a laminar flow case. As its name implies, DNS directly models the Navier-Stokes equations without recourse to subgrid modeling so for flows with a broad spectrum of motions (high Re) the cost can be prohibitive - the number of required grid points scaling with Re(exp 9/4) and the number of time steps with Re(exp 3/4). The middle road is provided by LES whereby the Navier-Stokes equations are formally

  11. Les Houches session LXXVII

    CERN Document Server

    Feigelman, Mikhail; Kurchan, Jorge; Dalibard, Jean

    2003-01-01

    Intended for graduate students in physics and chemistry, this book touches on granular matter, protein folding, phase separating and evolution kinetics. Taking glasses as a central theme, it presents the problem of slow dynamics from several angles, a ubiquitous feature in condensed matter, mechanics and biological physics. Some of the best established workers in the field present different theoretical and experimental approaches to the subject.

  12. Les bourses du CRDI appuient les futurs chefs de file dans le ...

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

    13 mai 2015 ... Un programme de bourses de recherche du CRDI appuie les recherches novatrices et renforce le leadership futur et les connaissances sur les TIC, les ... Internet, la radio communautaire et la vidéo participative, présentent un fort potentiel pour faire face aux répercussions des changements climatiques et ...

  13. Thermal conductivity of sintered UO{sub 2} under in-pile conditions; Conductibilite thermique de l'UO{sub 2} fritte dans les conditions d'utilisation en pile

    Energy Technology Data Exchange (ETDEWEB)

    Stora, J P; Bernardy De Sigoyer, B; Delmas, R; Deschamps, P; Lavaud, B; Ringot, C [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1964-07-01

    The temperature distribution in a stack of sintered UO{sub 2} cylinders has been studied both in the laboratory where the heat energy is produced by an axial heating element, and in-pile, where the heating is due solely to nuclear effects. Under a high thermal gradient the UO{sub 2} cracks both along radial planes and along pseudo-cylindrical surfaces: these latter act as thermal barriers to the heat flow, It is therefore an apparent thermal conductivity k{sub a}(T), lower than the intrinsic value k(T) of this parameter which is measured. The efficiency of these barriers decreases when the gap decreases and when the external pressure acting on the cracked stack increases: in the limiting case, for high values of the binding strain, k{sub a}(T) {approx_equal} k(T). In the domain of phonon conduction (T {<=} 1350 deg C), the expression kw.cm{sup -1}.C{sup -1}=1/(11+0.024*T) accounts for the real thermal conductivity. Above 1350 deg C the thermal conductivity increases. Two in-pile measurements up to 1250 deg C carried out using cartridges fitted with thermocouples confirm, within the limits of experimental error, the above expression and the qualitative effects of the binding strains. Similar tests have been carried out-of-pile and in-pile on the real shape of the EL-4 fuel 'pencils'. Out-of-pile, the influence of the initial free gap, of the nature of the gas filing the 'pencil' and of the external pressure have been studied; the results are compatible with the above interpretation; It appears that an external pressure of 60 kg/cm{sup 2} is insufficient to restore completely the thermal conductivity of the fuel. (authors) [French] La distribution de temperature dans un empilement de cylindres d'UO{sub 2} fritte est etudiee a la fois au laboratoire, ou l'energie calorifique est produite par un element chauffant axial, et en pile, ou l'echauffement est uniquement nucleaire. Sous gradient thermique eleve, l'UO{sub 2} se fracture a la fois suivant des plans radiaux et

  14. Les faits,une arme contre

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

    les anime. Les villages avoisinants s'en inspirent : neuf d'entre eux ont demandé des conseils pour aménager des potagers. Selon les habitants de Lilbouré, les autres veulent suivre leur exemple. Mais, rappelle leur porte-parole, le progrès a un coût : il faut s'organiser, participer aux réunions, verser ses cotisations, tenir ...

  15. Comment diffuser les savoirs à travers les Alpes ?

    Directory of Open Access Journals (Sweden)

    Wolfgang Pfefferkorn

    2009-03-01

    Full Text Available CIPRA’s Future in the Alps Project aims at showcasing examples of successful implementation and successful projects in the Alps, and making available to others the extensive pool of experience and practical knowledge that lies in these projects. But how to transfer knowledge in an area of some 14 million inhabitants with several linguistic and cultural regions in which thousands of projects are carried out each year, that all kinds of players who work and life in completely different contexts are able to learn and benefit from one another? How do you go about something like that?Le projet « Avenir dans les Alpes » de la CIPRA (Commission Internationale pour la Protection des Alpes a pour objectif de présenter des exemples de réalisations et de projets réussis dans les Alpes, et de mettre à disposition du public l’ensemble de l’expérience et des connaissances pratiques acquises dans le cadre de ces projets. Cependant, comment transférer les savoirs dans une zone comptant quelque 14 millions d’habitants, composée de plusieurs régions linguistiques et culturelles dans lesquelles des milliers de projets sont menés à bien chaque année, et dont tous les acteurs, qui travaillent et vivent dans des contextes complètement différents, sont capables d’apprendre et de tirer profit les uns des autres ? Comment aborder ce genre de cas ?

  16. Analytic catalog for the use of the nuclear physicists; Repertoire analytique a l'usage des physiciens nucleaires

    Energy Technology Data Exchange (ETDEWEB)

    Ballini, R.; Barloutaud, R.; Bernas, R.; Chaminade, R.; Cohen, R.; Conjeaud, M.; Cotton, E.; Faraggi, H.; Grjebine, T.; Laboulaye, H. de; Lehmann, P.; Leveque, A.; Levi, C.; Moreau, J.; Naggiar, V.; Olkowsky, J.; Papineau, L.; Papineau, L.; Prugne, P.; Schuhl, C.; Szteinsznaider, D.; Tzara, C.; Valladas, G. [Commissariat a l' Energie Atomique, Saclay(France). Centre d' Etudes Nucleaires; Marty, N.; Renard, G. [College de France, Lab. de Chimie Nucleaire (France)

    1952-07-01

    The problem of the documentation in nuclear physics becomes constantly more complex. Every week brings its share of publications, always more numerous and more varied. To remedy to this problem, we tried, at the Nuclear Physics Services of the CEA, to give to the documentation the character of a collective and systematized work. The present report covers the literature appeared between January 1, 1950 and July 1, 1951. (Volume 1: CEA report number 120; Volume 2: CEA report number 184). (M.B.) [French] Le probleme de la documentation en physique nucleaire devient sans cesse plus complexe. Chaque semaine apporte son lot de publications, toujours plus nombreuses et plus diversifiees. C'est pour essayer de porter remede a cet etat de choses que nous avons essaye, au service de Physique Nucleaire du C.E.A., de donner a la documentation le caractere d'un travail collectif systematise. Le present rapport couvre la litterature parue entre le 1 Janvier 1950 et le 1 Juillet 1951. (Tome 1: Rapport CEA numero 120; Tome 2: Rapport CEA numero 184). (M.B.)

  17. Analytic catalog for the use of the nuclear physicists; Repertoire analytique a l'usage des physiciens nucleaires

    Energy Technology Data Exchange (ETDEWEB)

    Ballini, R; Barloutaud, R; Bernas, R; Chaminade, R; Cohen, R; Conjeaud, M; Cotton, E; Faraggi, H; Grjebine, T; Laboulaye, H de; Lehmann, P; Leveque, A; Levi, C; Moreau, J; Naggiar, V; Olkowsky, J; Papineau, L; Papineau, L; Prugne, P; Schuhl, C; Szteinsznaider, D; Tzara, C; Valladas, G [Commissariat a l' Energie Atomique, Saclay(France). Centre d' Etudes Nucleaires; Marty, N; Renard, G [College de France, Lab. de Chimie Nucleaire (France)

    1952-07-01

    The problem of the documentation in nuclear physics becomes constantly more complex. Every week brings its share of publications, always more numerous and more varied. To remedy to this problem, we tried, at the Nuclear Physics Services of the CEA, to give to the documentation the character of a collective and systematized work. The present report covers the literature appeared between January 1, 1950 and July 1, 1951. (Volume 1: CEA report number 120; Volume 2: CEA report number 184). (M.B.) [French] Le probleme de la documentation en physique nucleaire devient sans cesse plus complexe. Chaque semaine apporte son lot de publications, toujours plus nombreuses et plus diversifiees. C'est pour essayer de porter remede a cet etat de choses que nous avons essaye, au service de Physique Nucleaire du C.E.A., de donner a la documentation le caractere d'un travail collectif systematise. Le present rapport couvre la litterature parue entre le 1 Janvier 1950 et le 1 Juillet 1951. (Tome 1: Rapport CEA numero 120; Tome 2: Rapport CEA numero 184). (M.B.)

  18. Les Fintech sont-elles une opportunité ou une menace pour les banques traditionnelles ?

    OpenAIRE

    Blanc, Aldwin; Sonney, Frédéric

    2018-01-01

    Dans ce travail, nous étudierons les potentielles opportunités et menaces que sont les Fintech pour les institutions bancaires. Cela nous permettra de savoir si, à l’avenir, ces entreprises vont s’imposer et remplacer les banques telles que nous les connaissons ou alors aider, forcer les acteurs traditionnels à effectuer leur révolution numérique pour répondre aux nouvelles attentes des clients. Afin de répondre à cette interrogation, les trois strates de l’environnement bancaire ont été anal...

  19. Territorialisation et enclaves littorales dans les îles de la Caraïbe

    Directory of Open Access Journals (Sweden)

    Michel Desse

    2008-04-01

    Full Text Available Les littoraux de la Caraïbe ont longtemps été considérés comme des espaces de l’envers, ouverts, libres, propriété de l’Etat donc de tous, opposables à la plantation qui hiérarchise la société, structure le paysage et identifie la richesse.Aujourd’hui, les littoraux constituent les centres fonctionnels des îles, annexés parfois privatisés, ils apparaissent fortement territorialisés. Les facteurs qui expliquent ces transformations sont multiples. Les îles connaissent une forte tertiairisation ...

  20. Les présages expliqués

    CERN Document Server

    Belly

    2015-01-01

    Extrait : ""Les Romains et les Grecs avaient emprunté aux Chaldéens la plupart des arts divinatoires : Ce que disent les caractères de l'Écriture. Ce que disent les lignes du visage. Ce que disent les traits du visage. Ce que disent les cartes, etc.""

  1. LES GOITRES PLONGEANTS : PARTICULARITES CLINIQUES ...

    African Journals Online (AJOL)

    SUBSTERNAL GOITERS : SPECIAL CLINICAL,. RADIOLOGICAL AND THERAPEUTIC. M. Ben Amor, S. Dhambri, I. Hariga, W. Abid, R. Hannachi, O. Ben Gamra, S. Zribi, CH. .... L'indication chirurgicale est formelle dans les goitres plon- geantsdevant le risque de détresse respiratoire aiguë met- tant en jeu le pronostic vital ...

  2. Les femmes et la terre

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

    La terre, qui relie les aspects économique, culturel, politique et juridique de la vie ..... Le plan stratégique de 2001-2011 à l'égard du secteur foncier (Ouganda, ...... nommées aux commissions par le ministère, le recrutement se fait au moyen ...

  3. Inegalites entre les garçons et les filles dans l'evaluation en ...

    African Journals Online (AJOL)

    Cette recherche se propose d'étudier les inégalités entre les garçons et les filles dans l'évaluation en Education Physique et Sportive dans les collèges et surtout de connaître leurs sentiments par vis-à-vis de cette évaluation. Cette étude aura pour cadre les établissements secondaires de Porto-Novo et environs.

  4. Modelization of physical phenomena in research reactors with the help of new developments in transport methods, and methodology validation with experimental data; Modelisation des phenomenes physiques dans les reacteurs de recherche a l'aide de developpements realises dans les methodes de transport et qualification

    Energy Technology Data Exchange (ETDEWEB)

    Rauck, St

    2000-10-01

    The aim of this work is to develop a scheme for experimental reactors, based on transport equations. This type of reactors is characterized by a small core, a complex, very heterogeneous geometry and a large leakage. The possible insertion of neutron beams in the reflector and the presence of absorbers in the core increase the difficulty of the 3D-geometrical description and the physical modeling of the component parameters of the reactor. The Orphee reactor has been chosen for our study. Physical models (homogenization, collapsing cross section in few groups, albedo multigroup condition) have been developed in the APOLLO2 and CRONOS2 codes to calculate flux and power maps in a 3D-geometry, with different burnup and through transport equations. Comparisons with experimental measurements have shown the interest of taking into account anisotropy, steep flux gradients by using Sn methods, and on the other hand using a 12-group cross section library. The modeling of neutron beams has been done outside the core modeling through Monte Carlo calculations and with the total geometry, including a large thickness of heavy water. Thanks to this calculations, one can evaluate the neutron beams anti-reactivity and determinate the core cycle. We assure these methods more accurate than usual transport-diffusion calculations will be used for the conception of new research reactors. (author)

  5. Les métamorphoses du livre

    OpenAIRE

    Chartier, Roger

    2015-01-01

    Après avoir étudié les conditions de production et de diffusion traditionnelles des livres lors des « Rendez-vous de l'édition », la Bibliothèque propose, en prolongement de ce cycle, les rencontres « Les rendez-vous de l'édition : le livre et le numérique », afin de donner au public des informations et des repères pour comprendre les évolutions en cours. En effet, les technologies numériques permettent de développer ou de renouveler de nombreux produits et services : édition en ligne, livre...

  6. Semaine alpine 2008 : innover (dans) les Alpes

    OpenAIRE

    Bourdeau, Philippe; Bourdeau, Philippe; Corneloup, Jean; Corneloup, Jean; Finger-Stich, Andréa; Finger-Stich, Andréa; Giraut, Frédéric; Giraut, Frédéric; Kohler, Yann; Kohler, Yann; Macchiavelli, Andrea; Macchiavelli, Andrea; Scheurer, Thomas; Scheurer, Thomas; Ullrich, Aurelia

    2009-01-01

    Ce premier dossier en ligne se penche sur une question de grande actualité : l’innovation, pour interroger les conceptions et mises en œuvre de démarches innovantes dans les contextes montagnards. Ces textes sont issus de la « Semaine alpine », qui s’est déroulée en juin 2008 à l’Argentière-La Bessée, dans les Hautes-Alpes (France). Ces « Semaines alpines », en alternance avec les « Forums alpins », rassemblent tous les deux ans des chercheurs et des acteurs locaux de l’ensemble de l’arc alp...

  7. LES of flow in the street canyon

    OpenAIRE

    Brechler Josef; Fuka Vladimír

    2012-01-01

    Results of computer simulation of flow over a series of street canyons are presented in this paper. The setup is adapted from an experimental study by [4] with two different shapes of buildings. The problem is simulated by an LES model CLMM (Charles University Large Eddy Microscale Model) and results are analysed using proper orthogonal decomposition and spectral analysis. The results in the channel (layout from the experiment) are compared with results with a free top boundary.

  8. LES of flow in the street canyon

    Directory of Open Access Journals (Sweden)

    Brechler Josef

    2012-04-01

    Full Text Available Results of computer simulation of flow over a series of street canyons are presented in this paper. The setup is adapted from an experimental study by [4] with two different shapes of buildings. The problem is simulated by an LES model CLMM (Charles University Large Eddy Microscale Model and results are analysed using proper orthogonal decomposition and spectral analysis. The results in the channel (layout from the experiment are compared with results with a free top boundary.

  9. In-pile experimental device for Sirene thermionic converters; Dispositif d'experimentation en pile des convertisseurs thermoioniques sirene

    Energy Technology Data Exchange (ETDEWEB)

    Bliaux, J; Durand, J; Lazare-Chopard, G [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1969-07-01

    The irradiation device described here, was built for in pile life tests of 100 We SIRENE converters. The nuclear converter is located in a sealed vacuum chamber, which is plugged at the lower end of a coaxial tubing acting as electrical leads. The output power is available on a variable resistive load on the bank of the reactor pool. Thermal, electrical and neutronic parameters of the converter are recorded. Since 1967, two permanent devices allowed five experiments in the swimming pool TRITON (CEN-FAR) and the results, obtained till now, are presented. (authors) [French] Le dispositif d'irradiation SIRENE decrit ici a ete concu en vue d'une etude statistique de performances de convertisseurs thermoioniques nucleaires de puissance unitaire 100 We. Le dispositif doit assurer la bonne marche du convertisseur en pile, permettre le changement de la position verticale du convertisseur dans le coeur, sortir du coeur la puissance electrique convertie sans degradation notable et enregistrer les differents parametres thermiques, electriques et neutroniques du convertisseur. Depuis 1967, deux dispositifs fonctionnent en permanence et ont permis de faire cinq experiences dans le reacteur piscine TRITON du CEN-FAR. Les resultats obtenus jusqu'a present, sont presentes. (auteurs)

  10. LES of the adverse-pressure gradient turbulent boundary layer

    International Nuclear Information System (INIS)

    Inoue, M.; Pullin, D.I.; Harun, Z.; Marusic, I.

    2013-01-01

    Highlights: • The adverse-pressure gradient turbulent boundary layer at high Re is studied. • Wall-model LES works well for nonequilibrium turbulent boundary layer. • Relationship of skin-friction to Re and Clauser pressure parameter is explored. • Self-similarity is observed in the velocity statistics over a wide range of Re. -- Abstract: We describe large-eddy simulations (LES) of the flat-plate turbulent boundary layer in the presence of an adverse pressure gradient. The stretched-vortex subgrid-scale model is used in the domain of the flow coupled to a wall model that explicitly accounts for the presence of a finite pressure gradient. The LES are designed to match recent experiments conducted at the University of Melbourne wind tunnel where a plate section with zero pressure gradient is followed by section with constant adverse pressure gradient. First, LES are described at Reynolds numbers based on the local free-stream velocity and the local momentum thickness in the range 6560–13,900 chosen to match the experimental conditions. This is followed by a discussion of further LES at Reynolds numbers at approximately 10 times and 100 times these values, which are well out of range of present day direct numerical simulation and wall-resolved LES. For the lower Reynolds number runs, mean velocity profiles, one-point turbulent statistics of the velocity fluctuations, skin friction and the Clauser and acceleration parameters along the streamwise, adverse pressure-gradient domain are compared to the experimental measurements. For the full range of LES, the relationship of the skin-friction coefficient, in the form of the ratio of the local free-stream velocity to the local friction velocity, to both Reynolds number and the Clauser parameter is explored. At large Reynolds numbers, a region of collapse is found that is well described by a simple log-like empirical relationship over two orders of magnitude. This is expected to be useful for constant adverse

  11. Un projet gagnant sur tous les tableaux : les moustiquaires ...

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

    15 juil. 2011 ... La trousse est un des principaux éléments du projet de marketing social des moustiquaires imprégnées (connue sous le sigle anglais SMITN) lancé par ... je ne crois pas que la Tanzanie aurait eu assez de preuves pour prendre la décision d'implanter les moustiquaires imprégnées à l'échelle du pays » ...

  12. Les femmes se tournent vers les arbres fourragers pour engraisser ...

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

    12 févr. 2018 ... Photo : CRDI / Bartay Au Mali, les moutons sont associés à des rites de passage traditionnels et à des fêtes religieuses, mais ils sont aussi une source importante de revenus. Toutefois, la disponibilité et le coût des aliments constituent une contrainte majeure en matière de production ovine, surtout en ...

  13. El perfil arquetípic de les marques

    Directory of Open Access Journals (Sweden)

    Sabrine Dornelles

    2013-02-01

    Full Text Available Aquest article presenta una manera fàcil d'establir què significa una marca per als públics. Per això, es basa en l'inconscient col · lectiu fonamentat en les creences que tenim tots els éssers humans sobre els déus de la mitologia grega. El mètode fonamentat en l'estudi qualitatiu que permet definir els atributs de l'inconscient col · lectiu, utilitza la metodologia experimental per a concretar en base a un test de recepció el significat de les marques. L'estudi mostra els detalls de la significació i la riquesa de les marques en aquest sentit. Els resultats de l'estudi ens indica que les tres marques estudiades representen elements dels següents arquetips: Nike el d'adolescent, celebritat, explorador, heroi i inventor; Adidas el d'esposa, inventor i artista; i Puma el d'adolescent i príncep.

  14. Etudes théoriques et expérimentales de la combustion dans les moteurs Diesel d'automobiles à injection directe et à préchambre Theoretical and Experimental Research on Combustion in Diesel Automotive Engines with Direct Injection and a Prechamber

    Directory of Open Access Journals (Sweden)

    Douaud A.

    2006-11-01

    Full Text Available Certaines techniques récemment développées pour la modélisation mathématique et les investigations expérimentales sur moteur Diesel sont présentées. On insiste sur l'importance de la validation croisée entre calcul et mesure. Taux d'injection, aérodynamique interne, développement du spray sont analysés en relation avec la géométrie des chambres de combustion. Des exemples, portant principalement sur des considérations de rendement énergétiques et d'émissions polluantes sont présentés à la fois sur le moteur Diesel à préchambre et le moteur Diesel à injection directe. Various techniques developed recently for the mathematical modeling and experimental investigating of diesel engines are described. Emphasis is placed on the importance of crosschecking between computing and measuring. The injection rate, internal aerodynamics and spray development are analyzed in relation to the geometry of combustion chambers. Examples mainly concerning matters of energy efficiency and pollutant emissions are given for diesel engines both with a prechamber and with direct injection.

  15. Synthesis and purification of some alkyl phenanthrenes and presentation of their infrared, ultraviolet, nuclear magnetic resonance and mass spectra; Synthese et purification de quelques alcoylphenanthrenes et presentation ds leurs spectres d'absorption infrarouge, ultraviolette, de resonance magnetique nucleaire et de masse

    Energy Technology Data Exchange (ETDEWEB)

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

    1965-01-01

    We have carried out the synthesis of: - phenanthrene - its five monomethyl derivatives - three dimethyl derivatives - two trimethyl derivatives. We have then purified these products as well as a certain number of others obtained from various sources. We have been able to obtain in the majority of cases, a purity of 99.5 per cent or over, these figures being obtained by low voltage mass spectrometry. Finally we have recorded the infrared, ultraviolet, nuclear magnetic resonance and mass spectra of these products for which an atlas has been drawn up. (author) [French] Nous avons realise la synthese: - du phenanthrene - de ses cinq derives monomethyles - de trois de ses derives dimethyles - de deux de ses derives trimethyles. Nous avons ensuite purifie ces produits ainsi qu'un certain nombre d'autres que nous avons obtenus de sources differentes. Nous avons pu atteindre, dans la plupart des cas, une purete egale ou superieure a 99,5 pour cent, chiffres determines par la spectrometrie de masse a basse tension. Enfin, nous avons enregistre les spectres infrarouges, ultraviolets, de resonance magnetique nucleaire et de masse de ces produits dont nous avons fait un atlas. (auteur)

  16. Communications of 15 November 1999 Received from Member States Regarding the Export of Nuclear Material and of Certain Categories of Equipment and Other Material; Communications En Date Du 15 Novembre 1999 Recues D'Etats Membres Concernant L'Exportation De Matieres Nucleaires Et De Certaines Categories D'Equipements Et D'Autres Matieres

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-03-15

    The Director General of the International Atomic Energy Agency has received letters of 17 October 1996 from the Resident Representatives of Argentina, Australia, Austria, Bulgaria, Canada, the Czech Republic, Denmark, Finland, France, Germany, Greece, Hungary, Ireland, Italy, Japan, Republic of Korea, the Netherlands, Norway, Poland, Portugal, Romania, the Russian Federation, the Slovak Republic, South Africa, Spain, Sweden, the United Kingdom, and the United States of America, concerning the export of nuclear material and of certain categories of equipment and other material [French] Le Directeur general de l'Agence internationale de l'energie atomique a recu des lettres datees du 15 novembre 1999 que les representants permanents des pays suivants lui ont adressees au sujet de l'exportation de matieres nucleaires et de certaines categories d'equipements et d'autres matieres : Afrique du Sud, Allemagne, Argentine, Australie, Autriche, Belgique, Bulgarie, Canada, Coree (Republique de), Danemark, Espagne, Etats-Unis d'Amerique, Finlande, France, Grece, Hongrie, Irlande, Italie, Japon, Luxembourg, Norvege, Pays-Bas, Pologne, Portugal, Republique slovaque, Republique tcheque, Roumanie, Royaume-Uni, Suede, Suisse, Turquie et Ukraine.

  17. The structure of nuclear matter; La structure de la matiere nucleaire

    Energy Technology Data Exchange (ETDEWEB)

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

    1959-07-01

    Report on the most recent developments in the theory of systems of interacting fermions. After having given the general form of the ground state energy in perturbation theory, one indicates the terms whose summation tends to the Brueckner approximation. The numerical results obtained with this theory are briefly mentioned. A discussion is given about the difficulty occurring in the case of potentials which are attractive near the Fermi surface due to the existence of the Cooper bound states. The main ideas of the proof of the Van Hove Hugenholtz theorem on the Fermi energy are indicated and its implications for the Brueckner theory are given. The extension of the methods described here to statistical mechanics are briefly mentioned. In the discussion, Professor Brueckner reports on the most recent results concerning the application of his theory to finite nuclei. Professor Migdal reviews the results which he has obtained with the method of Green's functions on the superconducting properties of finite nuclei. Professor Weisskopf gives a qualitative explanation of the success of the Brueckner theory. (author) [French] Rapport sur les recents travaux portant sur la theorie des systemes de fermions en interaction. Apres avoir donne la forme generale du developpement de l'energie de l'etat fondamental dans la theorie des perturbations, on indique les termes dont la sommation conduit a l'approximation de Brueckner. Les resultats numeriques obtenus a l'aide de cette theorie sont brievement mentionnes. Une discussion est donnee de la difficulte survenant dans le cas des potentiels attractifs au voisinage de la surface de Fermi par suite de l'existence des etats lies de Cooper. Les idees essentielles de la demonstration du theoreme de Van Hove et Hugenholtz sur l'energie de Fermi sont indiquees ainsi que ses consequences pour la theorie de Brueckner. L'extension des methodes decrites a la Mecanique Statistique est brievement mentionnee. Dans la discussion, le professeur

  18. The Enrico Fermi Atomic Power Plant; La centrais nucleaire Enrico Fermi; Atomnaya ehlektrostantsiya im Ehnriko Fermi.; La central nucleoelectrica Enrico Fermi

    Energy Technology Data Exchange (ETDEWEB)

    Hartwell, R. W. [Power Reactor Development Company, Detroit, MI (United States)

    1963-10-15

    sodium-water reaction took place in the No. 1 steam generator. The rupture disc, which was installed for such an eventuality, operated correctly. The cause and effect of this failure is currently being investigated. Completion of pre-operational testing. Anticipating the issuance of a low power licence, the final assembly and test programme is being completed in March. (author) [French] La construction de la centrale nucleaire Enrico Fermi, equipee d'un reacteur surgenerateur a neutrons rapides de 100 MWe, a ete virtuellement terminee en decembre 1961. Au cours des derniers 18 mois, on a minutieusement verifie les circuits et les parties constitutives. Ce programme de verifications avant la mise en service a ete tres utile pour verifier les plans et determiner les modifications a y apporter. Tous les problemes ont pu etre resolus. Voici la liste des principales modifications: Bouclier de graphite. En decembre 1960, on a rempli le circuit primaire de sodium liquide et on a procede a des essais tres pousses. Lorsqu'on a rouvert l'enceinte de protection primaire, apres les essais a 540{sup o}C, on a constate que la plus grande partie des blocs de graphite entourant le reacteur s'etait deterioree. Ces blocs, destines a supporter de hautes temperatures, etaient impregnes de bore; ils s'etaient dilates et avaient perdu leur resistance. Une analyse approfondie a montre que le liant du graphite avait cede. On a decide de remplacer tout le graphite, d'utiliser du carbure de bore a la place du bore, d'assujettir les blocs par des dispositifs mecaniques et de maintenir l'humidite a la valeur minimum. Modifications a l'interieur du caisson du reacteur. On a procede a des reparations et modifications pour supprimer la cause du collage des barreaux et les dommages qui en resultaient, et pour prevenir d'autres defaillances du mecanisme de manutention des cartouches. Pour ce faire, on a du retirer le mecanisme de manutention et vider le caisson contenant le sodium. Des specialistes

  19. Legal and Administrative Problems of Controlling the Disposal of Nuclear Wastes in the Sea; Problemes Juridiques et Administratifs Poses par le Controle de l'Elimination des Dechets Nucleaires dans la Mer; 041f 0420 041e 0414 ; Problemas Juridicos y Administrativos que Plantea el Control de la Evacuacion de Desechos Nucleares En El Mar

    Energy Technology Data Exchange (ETDEWEB)

    Hydeman, Lee M.; Berman, William H. [Atomic Energy Research Project, University of Michigan Law School (United States)

    1960-07-01

    The basic purpose of the paper is to present some approaches to multinational control of the sea disposal of nuclear wastes, considering both the type of international .control which may be appropriate and the means for accomplishing such control. First, the authors give a brief description of the kind of control which appears to be necessary in protecting public health against the hazards of the disposal of wastes in the sea. The second part consists of a general analysis of the legal problems posed by nuclear wastes. Emphasis is placed on the authority of coastal states to impose unilateral control on the disposal of wastes by other nations if such disposal might adversely affect their interests. The authors inquire into the adequacy of legal remedies as well as the possible rule of law regarding the prevention of damage from waste disposal and the apportionment of liability in the event that such damage does occur. The third part is an analysis of how other problems of control have been handled, both unilaterally and multilaterally. The final part consists of an inquiry into various means of internationally controlling the sea disposal of nuclear wastes. The role of existing international bodies in the maintenance of continuing administrative control at the international level is mentioned. (author) [French] Le but essentiel du memoire est d'exposer diverses facons d'envisager le probleme du controle multinational de l'evacuation des dechets nucleaires dans l'eau de mer, en examinant a la fois le type de controle international approprie et les moyens de le mettre en oeuvre. La premiere partie contiendra une description succincte du genre de controle qui semble necessaire pour la protection de la sante publique contre les effets de l'evacuation des dechets dans la mer. La deuxieme partie consistera en une analyse generale des problemes juridiques poses par. l'elimination des dechets nucleaires. Les auteurs traiteront particulierement du droit des Etats riverains

  20. Le CERN et les Institutions

    CERN Document Server

    Barbalat, Oscar

    1996-01-01

    Une première partie de l'exposéŽ sera consacrée àˆ une brève description des principaux organes de l'Union EuropéŽennne: Conseil, Parlement et Commission ainsi que la structure de la Commission. On passera ensuite en revue le Programme-Cadre de Recherche et DéŽveloppement Technologique et les principaux programmes spéŽcifiques auxquels participe le CERN (ESPRIT, ACTS, TMR) On situera ensuite les autres organisations et initiatives scientifiques européŽennes (ESA, ESO, ESRF, JET, ISTC, EUREKA, ...) pour terminer par une brève revue des relations entre le CERN avec ces difféŽrentes institutions en déŽveloppant plus particulièrement celles avec la Commission.

  1. Post-Construction Testing of the Elk River, Hallam and Piqua Power Reactor Plants; Essais apres construction des centrales nucleaires d'Elk River, de Hallam et de Piqua; Predehkspluatatsionnoe ispytanie Ehlk-riverskoj, Khehlpemskoj i Pikuaskoj ehnergeticheskikh reaktornykh ustanovok; Ensayos posteriores a la construccion de las centrales nucleoelectricas de Elk River, Hallam y Piqua

    Energy Technology Data Exchange (ETDEWEB)

    Pursel, C. A. [United States Atomic Energy Commission, Argonne, IL (United States)

    1963-10-15

    numerous, observed or suspected, deficiencies or malfunctions of components which led to additional testing and analyses. In some instances, repair or modification of components was necessary to correct fabrication or engineering errors. Major problem areas are discussed: Elk River Reactor. Discovery of cracks in portions of the reactor vessel surface cladding led to extensive investigations and analyses and required some repairs and vessel modifications. Insufficient steam separation capacity required replacement and modification of some reactor vessel internal hardware. Hallam Nuclear Power Facility. Entrainment of the helium cover gas led to modifications of the secondary sodium loops. Failure of a tube in the intermediate (sodium to sodium) heat exchanger led to analyses to determine the cause of failure followed by removal and repair of the heat exchanger. Piqua Nuclear Power Facility. Chemical cleaning of the piping system damaged several valves which required mere repair or replacement. Leaks in the organic coolant and steam tracing systems caused repeated delays. After completion of the necessary repairs and modifications, the actual performance characteristics of each of the three reactors closely matched design predictions. (author) [French] Les resultats des essais apres construction de trois centrales nucleaires, dans le cadre du programme de demonstration des centrales nucleaires de la Commission de l'energie atomique des Etats-Unis (CEA-EU), permettront peut-etre de faire certaines generalisations concernant cette phase de la construction et de l'exploitation des centrales. Ces trois centrales, le reacteur de puissance d'Elk River (ERR), la centrale nucleaire de Hallam (HNPF), et la centrale nucleaire de Piqua (PNPF), appartiennent a trois filieres differentes: reacteur a eau bouillante a circulation naturelle, reacteur a graphite et a sodium et reacteur ralenti et refroidi par un fluide organique. La periode des essais apres construction a commence a la fin

  2. La Tentation et les savoirs

    Directory of Open Access Journals (Sweden)

    Gisèle Séginger

    2009-01-01

    Full Text Available Malgré son inactualité apparente, La Tentation de Saint Antoine se rattache à une série de savoirs, de recherches historiques, d’interrogations qui caractérisent son époque et définissent une configuration épistémologique. Les savoirs sont impliqués à deux niveaux : dans l’organisation de la poétique de l’œuvre, dans les représentations de l’œuvre. Flaubert utilise des savoirs historiques, anthropologiques et psychiatriques qui légitiment l’organisation du texte et les déconstruit en même temps. Il invente une nouvelle forme de grotesque – le grotesque des idées – et met en abyme un questionnement sur les savoirs qui évolue de la première Tentation à celle de 1874.Despite its apparent irrelevancy to Flaubert's time, La Tentation de Saint Antoine is linked to a net of knowledge, historical research, questions that characterize a period and define an epistemological configuration. These types of knowledge are at play on two levels: in the organization of the poetics of the work and in its representations. Flaubert uses historical, anthropological and psychiatric knowledge which legitimates the organization of the text while at the same time he deconstructs this body of knowledge. Flaubert invents a new form of grotesque – the grotesque of ideas – and, in a mise-en-abyme from the first Tentation to the 1874 version, he questions these fields of knowledge.

  3. Du mucilage chez les algues

    NARCIS (Netherlands)

    Wildeman, de É.

    1942-01-01

    En examinant en 1939 dans une note présentée à l’Académie des Sciences de Belgique une étude de M. Ronse, nous avons été amené à reprendre des considérations sur les mucilages des végétaux et en particulier sur ceux des algues (22; 31). Déjà en 1891, dans nos ”Observations algologiques“ nous avons

  4. Prise en charge des intoxications par envenimation chez les enfants ...

    African Journals Online (AJOL)

    Les signes cliniques étaient dominés par les douleurs (98%) suivies des hémorragies (73,80%) pour les morsures de serpent, la douleur pour les piqures de scorpion (100%) et les oedèmes pour les piqures d'abeilles (100%). Les cas de morsure de serpent ont été traités par le sérum antivenimeux polyvalent. Conclusion: ...

  5. Les découvreurs

    CERN Document Server

    Boorstin, Daniel

    1986-01-01

    Sous une forme vivante, enlevée, très personnelle, Les Découvreurs raconte la plus grande épopée de l'homme : celle de sa quête pour découvrir le monde qui l'entoure. Daniel Boorstin s'écarte volontairement de la traditionnelle et fastidieuse énumération des batailles, des naissances d'empires et des grands règnes : avec lui, l'histoire de notre monde devient une féerie de découvertes et de commencements. En chaque découverte d'importance, que ce soit celle de l'Amérique par Christophe Colomb ou celle de la relativité par Einstein, il voit un épisode d'une biographie. Les héros de la saga qu'il nous raconte sont des hommes dotés d'une insatiable frénésie de connaissance et d'un courage exemplaire pour affronter l'inconnu. Daniel Boorstin nous fait découvrir sous un jour nouveau des noms familiers : Hérodote, Ptolémée, Marco Polo, Copernic, Newton, Marx, Freud, et ressuscite également quelques figures remarquables oubliées de l'histoire. Pour quelles raisons les Chinois n'ont-ils pas...

  6. Experimental study of the effect of an electric field on thermal exchanges under forced convection with gaseous carbon anhydride in presence of the radiation of the Melusine pile; Etude experimentale de l'effet d'un champ electrique sur les echanges thermiques en convection forcee avec l'anhydride carbonique gazeux en presence du rayonnement de la pile Melusine

    Energy Technology Data Exchange (ETDEWEB)

    Perroud, P.; Rebiere, J.; Verdier, J.

    1961-01-21

    Previous studies showed that, under free or forced convection, the application of a non-uniform electric field with a sufficient intensity at the neighbourhood of the heating elements resulted in a significant improvement of the thermal exchange coefficient under some flow rate and pressure conditions. But these improvements first required the creation of ions in the gas (shock ionization and existence of a corona effect above a sufficient voltage). This document therefore report further studies performed at the neighbourhood of the Melusine atomic pile which would provide ionizing radiations of much greater intensity. The objectives were, on the one hand, a global verification of work hypotheses imagined for the exchange improvement mechanism, and, on the other hand, to obtain data on the conditions under which this exchange improvement mechanism could be used in channels of a reactor. The authors present the instrumentation (measurement cells, gas circuit, heating circuit, high voltage circuit), describe how physical values are measured (pressure, gas flow rate, temperature of the heating element, gas temperature, high voltage). They describe how they compare powers exchanged under forced convection between dioxide carbon and a heated wire with or without external ionizing radiations, and report the various performed calculations (power supplied to the gas, temperature shift, Nusselt and Reynolds numbers). They report and discuss experimental results obtained outside the pile without ionizing radiations, and within the pile in presence of a ionizing radiation [French] Les essais ont ete effectues dans les conditions suivantes: nombres de Reynolds variant de 20.000 a 80.000, pression de 11 a 21 kg/cm{sup 2}, temperatures moyennes de l'element chauffant de 200 a 600 deg. C, tension electrique de 0 a 30 kV eff et intensite maximum du rayonnement γ, 3x10{sup 7} roentgen/h. On a confirme, hors pile, que l'augmentation de la puissance echangee, au dessus du seuil d

  7. Numerical and experimental study of the mixture of engine jets in the wake vortices of an airline aircraft; Etude numerique et experimentale du melange des jets de moteur dans les tourbillons de sillage d'un avion de ligne

    Energy Technology Data Exchange (ETDEWEB)

    Brunet, St.

    1999-07-01

    This study is a contribution to the understanding of the formation and duration of aircraft condensation trails. The development of a numerical code based on the direct resolution of the 3-D compressible Navier-Stokes equations has been done first. Then, an experiment has been carried out in a wind tunnel to analyze the problem of the mixture of heated jets in a wing wake. A first validation of the numerical method has been carried out from bibliographic results and measurements of the mixture evolution of an inert tracer contained in the engine jets during a flight test. In order to characterize the condensation inside the wake, the evolution of the local water vapor saturation ratio has been calculated. The influence of the Crow instability on the mixture of effluents in the high atmosphere is also shown. Finally, a comparison is made between the numerical simulation results and the experimental measurements obtained in this study. The numerical results have also permitted to characterize the low scale exchange mechanisms between a turbulent jet and a swirl flow. (J.S.)

  8. Notes on the Start-Up of the Latina Power Station; Notes concernant le demarrage de la centrale nucleaire de Latina; Zapusk ehlektrostantsii Latina; Notas sobre la puesta en marcha de la central electrica de Latina

    Energy Technology Data Exchange (ETDEWEB)

    Calabria, G.; Gualtieri, G. [AGIP Nucleare, Milano (Italy)

    1963-10-15

    Information is given on the start-up of the first Italian nuclear power plant, the Latin Power Station, designed for an electrical output of 200 MW, incorporating a natural uranium-gas-graphite reactor. After a brief description of the main characteristics of the station, details are given on die performance of the final tests of the plant, on the fuel loading and on the sequence of commissioning operations, measurements and controls subsequent to the criticality attained. The operations for the start-up and connection of the station to the electrical network are treated. The organization problems relevant to the station operation including personnel preparation and qualification, safety measures, are also illustrated. (author) [French] Le memoire donne des renseignements sur le demarrage de la premiere centrale nucleaire italienne, la centrale de Latina, dont la puissance electrique est de 200 MW et qui fonctionne avec un reacteur du type uranium naturel-gaz-graphite. Apres une breve description des caracteristiques essentielles de la centrale, des explications detaillees sont donnees sur les resultats des derniers essais auxquels elle a ete soumise, sur le chargement du combustible et sur la serie des operations de mise en service, des mesures et des verifications auxquelles il a ete procede lorsque l'etat critique a ete atteint. Les operations de demarrage et de raccordement de la centrale au reseau electrique sont etudiees dans le memoire, ainsi que les problemes d'organisation que pose l 'exploitation de la centrale, notamment en ce qui concerne la formation du personnel et les mesures de securite. (author) [Spanish] Se comunican datos sobre la puesta en marcha de la primera central nucleoelectrica italiana, en Latina, proyectada para desarrollar una potencia de 200 MW (e), que se basa en un reactor de uranio natural moderado por grafito u refrigerado por gas. Despues de describir brevemente las caracteristicas de la central, se dan detalles sobre el

  9. Technical safety Organisations (TSO) contribute to European Nuclear Safety; Les organismes techniques de surete (TSO) au service de la surete nucleaire europeenne

    Energy Technology Data Exchange (ETDEWEB)

    Repussard, J. [Institut de radioprotection et de surete nucleaire - IRSN, 92 - Clarmart (France)

    2010-11-15

    Nuclear safety and radiation protection rely on science to achieve high level prevention objectives, through the analysis of safety files proposed by the licensees. The necessary expertise needs to be exercised so as to ensure adequate independence from nuclear operators, appropriate implementation of state of the art knowledge, and a broad spectrum of analysis, adequately ranking the positive and negative points of the safety files. The absence of a Europe-wide nuclear safety regime is extremely costly for an industry which has to cope with a highly competitive and open international environment, but has to comply with fragmented national regulatory systems. Harmonization is therefore critical, but such a goal is difficult to achieve. Only a gradual policy, made up of planned steps in each of the three key dimensions of the problem (energy policy at EU level, regulatory harmonization, consolidation of Europe-wide technical expertise capability) can be successful to achieve the required integration on the basis of the highest safety levels. TSO's contribute to this consolidation, with the support of the EC, in the fields of research (EURATOM-Programmes), of experience feedback analysis (European Clearinghouse), of training and knowledge management (European Training and Tutoring Institute, EUROSAFE). The TSO's network, ETSON, is becoming a formal organisation, able to enter into formal dialogue with EU institutions. However, nuclear safety nevertheless remains a world wide issue, requiring intensive international cooperation, including on TSO issues. (author)

  10. Theme day: corrosion and surface treatments in nuclear facilities. Proceedings; Journee Thematique: Corrosion et Traitements de surface dans les Installations Nucleaires. Recueil des presentations

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2012-02-15

    This document brings together the available presentations given at the theme day organized by the Bourgogne Nuclear Pole on the topic of corrosion and surface treatments in nuclear facilities. Eleven presentations (slides) are compiled in this document: 1 - Introduction - PNB centre of competitiveness and R and D activities (A. Mantovan, PNB); 2 - Corrosion damage (M. Foucault, Areva NP - Centre Technique Le Creusot); 3 - Corrosion mechanisms (R. Oltra, UB-ICB); 4 - Examples of expertise management (C. Duret-Thual, Institut de la corrosion/Corrosion Institute); 5 - General framework of surface treatments (C. Nouveau, ENSAM Cluny Paris Tech); 6 - Surfaces et interfaces characterisation - Part A (C. Langlade, Y. Gachon, UTBM and HEF); 7 - Surfaces et interfaces characterisation - Part B (C. Langlade, Y. Gachon, UTBM and HEF); 8 - Ion beam surface treatment (Y. Le Guellec, Quertech Ingenierie); 9 - Impact surface treatment (G. Saout, Sonats); 10 - Metal oxides Characterisation by US laser (R. Oltra, UB-ICB); 11 - Detection and Characterisation of intergranular corrosion (Y. Kernin, Stephane Bourgois, Areva Intercontrole)

  11. Questions about the future of the nuclear energy; Les interrogations sur l'avenir de l'energie nucleaire

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-12-15

    The nuclear energy became a society subject much debated. This analysis discusses in three chapters the different interrogations concerning the nuclear energy: the comparison between the different energy sources to justify the preservation of the nuclear energy in France and in the world, the compatibility of the nuclear energy with the different socio-economic choices as the main condition of its development, and the role of the Government to transform the energy policy on the society choice. (A.L.B.)

  12. Plutonium: resuspension of aerosols in nuclear installations: bibliographic survey; Le plutonium: mise en suspension d'aerosols dans les installations nucleaires: synthese bibliographique

    Energy Technology Data Exchange (ETDEWEB)

    Guetat, Ph; Monfort, M; Armand, P [CEA Bruyeres-le-Chatel, Dept. Analyse Surveillance Environnement, Service Radioanalyse Chimie Environnement, 91 (France); Alloul-Marmor, L [Societe APTUS, 78 - Versailles (France)

    2006-07-01

    This document presents an analysis and a bibliographical synthesis of the studies on resuspension factors for plutonium. It aims at helping the engineers of safety to specify the scenarios of accidents which relate to their activities and to bring elements justified for the definition of their term-source 'installation' in the safety reports of the installations. (authors)

  13. Information note about the protection of nuclear facilities against aircraft crashes; Note d'information sur la protection des installations nucleaires contre les chutes d'avions

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-07-01

    The protection of nuclear facilities against external risks (earthquakes, floods, fires etc..) is an aspect of safety taken into consideration by the French authority of nuclear safety (ASN). Concerning the aircraft crashes, the fundamental safety rules make three categories of aircraft: the small civil aircraft (weight < 5.7 t), the military aircraft, and the commercial aircraft (w > 5.7 t). Nuclear facilities are designed to resist against crashes of aircraft from the first category only, because the probability of the accidental crash of a big aircraft are extremely low. This document comprises an information note about the protection of nuclear facilities against aircraft crashes, a dossier about the safety of nuclear facilities with respect to external risks in general (natural disasters and aircraft crashes), and an article about the protection of nuclear power plants against aircraft crashes (design, safety measures, regulation, surveillance, experience feedback). (J.S.)

  14. International reactions after the resumption of nuclear tests: lot of noise for nothing?; Les reactions internationales a la reprise des essais nucleaires: beaucoup de bruit pour rien?

    Energy Technology Data Exchange (ETDEWEB)

    Montesquieu, E. de

    1996-07-01

    In 1995, the French President announced that France would perform an ultimate campaign of nuclear tests before a complete banishment as soon as spring 1996. The campaign effectively ended on time and six tests took place between September 5, 1995 and January 27, 1996. The disarmament process went on and the international negotiations in progress at that time were not affected by the French policy. However, this campaign has caused a strong emotion, if not in the entire World, at least in part of the planet and in particular in Western Europe. This report analyses the reactions from the different governments and from the public opinion and shows their impact on the French diplomacy. Content: Part 1 - general considerations: 1 - lot of noise for nothing?: the objectives of French diplomacy; the acts (a quasi lack of sanctions, a temporary degradation of our relations with a limited number of countries); the rhetoric (diplomatic regrets in first time, slip-ups in the second time, the public opinion weight); 2 - the lessons learnt: the opinion and the management of the foreign policy (the image of France, the communication fight); the geopolitical lessons (European Union: community solidarity and European defense; the South Pacific area); 3 - a case study: Japan: the time of uncertainties (domestic situation, external policy); the Japanese reactions after the tests resumption. Part 2 - synthesis of reactions after the resumption of nuclear tests by France: Pacific bordering countries (South Pacific, Latin America); Western Europe countries; non-European countries; Conclusions.

  15. The bad debt of nuclear responsibility; L'heritage empoisonne du nucleaire - De la conduite a suivre pour reduire les risques

    Energy Technology Data Exchange (ETDEWEB)

    Haverkamp, J. [Greenpeace Europe (France)

    2010-11-15

    Nuclear regulation plays an important role in keeping the visible and invisible threats of radioactivity at bay. This article argues that the largest gains in nuclear safety can be made if nuclear activities with economically, socially and environmentally viable alternatives (such as nuclear energy and nuclear weapons) are phased out - similarly to what has been done for toxic substances. Unless this takes place, the legacy of radioactive waste for future generations will only increase. In this respect, the article highlights the importance of accountability, independence and transparency of nuclear regulators to contain the risks stemming from radioactivity. In the interest of safety, other uses of nuclear technology should, as a rule, apply the best available technology and the best regulatory practice. As is made clear in the article, the EURATOM Nuclear Safety Directive, adopted in 2009, hardly addresses any of these issues. The article ends on a set of demands from Greenpeace to meet the challenges posed by nuclear safety, concluding that there is still a long way to go before the sector can be considered even reasonably safe. (author)

  16. Energy of ions 3{<=}Z{<=}10 in Ilford C2 nuclear emulsions; Parcours - energie des ions 3{<=}Z{<=}10 dans les emulsions nucleaires ilford C2

    Energy Technology Data Exchange (ETDEWEB)

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

    1956-07-01

    The relationship between the path and energy of ions with 3{<=}Z{<=}10 in Ilford C2 nuclear emulsions is studied. It determined the average state of charge of ions in each velocity intervals. Results are given in a table for {sub 2}He, {sub 3}Li, {sub 4}Be, {sub 5}B, {sub 6}C, {sub 7}N, {sub 8}O and {sub 10}Ne. For each velocity interval, it is possible to apply the Blackett relation which links, for the same velocity, the path {delta}R of a particle with M (mass) and Z (charge) to the path {delta}R' of a particle with M' and Z'. Results are given in tables and graphics representing the particles energy with the particles path. (M.P.)

  17. Development of nuclear medicine techniques - radiation protection issues for patients; Evolution des techniques en medecine nucleaire - Enjeux de radioprotection pour les patients

    Energy Technology Data Exchange (ETDEWEB)

    Marchandise, Xavier [Faculte de Medecine de Lille, F-59045 Lille Cedex (France)

    2011-07-15

    Nuclear medicine uses radioactive isotopes for diagnostic or therapeutic purposes. The radiation protection culture is now well-anchored in the training of nuclear medicine specialists in France and must remain at the highest possible level. However, practices change and the immediate medical - or even media - interest in new equipment and new tracers must not obscure the fundamentals of patient radiation protection. Particular vigilance is today required with regard to two aspects: - children; - the corresponding computed tomography. (author)

  18. Life time of nuclear power plants and new types of reactors; La duree de vie des centrales nucleaires et les nouveaux types de reacteurs

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2003-05-01

    This report, realized by the Evaluation Parliamentary Office of scientific and technological choices, aims to answer simple but fundamental questions for the french electric power production. What are the phenomena which may limit the exploitation time of nuclear power plants? How can we fight against the aging, at which cost and with which safety? The first chapter presents the management of the nuclear power plants life time, an essential element of the park optimization but not a sufficient element. The second chapter details the EPR and the other reactors for 2015 as a bond between the today and tomorrow parks. The last chapter deals with the necessity of efforts in the research and development to succeed in 2035 and presents other reactors in project. (A.L.B.)

  19. Report on the possibilities of long-term storage of irradiated nuclear fuels; Rapport sur les possibilites d'entreposage a long terme de combustibles nucleaires irradies

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-07-01

    This report aims at giving a legislative aspect to the many rules that govern the activities of the back-end of the fuel cycle in France. These activities concern the unloading of spent nuclear fuels, their reprocessing, storage, recycling and definitive disposal. The following points are reviewed and commented: the management of non-immediately reprocessed fuels (historical reasons of the 'all wastes reprocessing' initial choice, evolution of the economic and political context, the future reprocessing or the definitive disposal of spent fuels in excess); the inevitable long-term storage of part of the spent fuels (quantities and required properties of long-term stored fuels, the eventuality of a definitive disposal of spent fuels); the criteria that long-term storage facilities must fulfill (confinement measures, reversibility, surveillance and control during the whole duration of the storage); storage concept to be retained (increase of storage pools capacity, long-term storage in pools of reprocessing plants, centralized storage in pools, surface dry-storage on power plant sites, reversible underground storage, subsurface storage and storage/disposal in galleries, surface dry-storage facilities); the preliminary studies for the creation of long-term storage facilities (public information, management by a public French organization, clarifying of the conditions of international circulation of spent fuels); problems linked with the presence of foreign spent fuels in France (downstream of the reprocessing cycle, foreign plutonium and wastes re-shipment); conclusions and recommendations. (J.S.)

  20. 7th international conference on Nuclear microprobe technology and applications; 7. conference internationale sur la technologie et les applications des microsondes nucleaires

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-07-01

    This colloquium gives an up-to-date report on the continuously advancing applications and development of microbeam technology. It presents abstracts and oral contributions in the following domains: microprobes facilities, analysis techniques, imaging techniques, micro-ion beam modification of materials, microelectronics, applications in Material Sciences in Biology in Medicine in earth and planetary Sciences in environment in art in archaeology, alternative techniques. (A.L.B.)

  1. Plutonium: resuspension of aerosols in nuclear installations: bibliographic survey; Le plutonium: mise en suspension d'aerosols dans les installations nucleaires: synthese bibliographique

    Energy Technology Data Exchange (ETDEWEB)

    Guetat, Ph.; Monfort, M.; Armand, P. [CEA Bruyeres-le-Chatel, Dept. Analyse Surveillance Environnement, Service Radioanalyse Chimie Environnement, 91 (France); Alloul-Marmor, L. [Societe APTUS, 78 - Versailles (France)

    2006-07-01

    This document presents an analysis and a bibliographical synthesis of the studies on resuspension factors for plutonium. It aims at helping the engineers of safety to specify the scenarios of accidents which relate to their activities and to bring elements justified for the definition of their term-source 'installation' in the safety reports of the installations. (authors)

  2. The formal notices of the French authority of nuclear safety; Les mises en demeure de l'autorite de surete nucleaire

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2002-07-01

    The French authority of nuclear safety (ASN) publishes on its web site (http://www.asn.gouv.fr) the formal notices and official statements addressed by the ASN to the concerned responsible persons (operators of nuclear facilities, directors of companies etc..) when anomalies requiring a corrective action have been noticed during on-site or off-site safety inspections. This document brings together the formal notices addressed by the ASN since June 2000 and up to April 2002. (J.S.)

  3. Should evacuation conditions after a nuclear accident be revised?; Faut-il revoir les conditions d'evacuation a la suite d'un accident nucleaire?

    Energy Technology Data Exchange (ETDEWEB)

    Nifenecker, H.

    2011-07-01

    The author proposes to draw lessons from the Fukushima accident, notably in the field of post-accident management. He discusses the definition of an as widely understandable as possible method of description of risks related to irradiations after a nuclear accident. As these irradiations are mainly low dose ones which have a carcinogenic effect, he proposes to assess the average life expectancy loss due to an irradiation. Then, this risk can be easily compared with other risks like air pollution, smoking and passive smoking, and so on. Then, once this risk assessment method is well defined, it is possible to associate the inhabitants of contaminated areas to the post-accident management. They could then decide to go back to their homes or not with full knowledge of the facts

  4. Researches on nuclear wastes. Knowledge gained and perspectives at the 2006 date line; Recherches sur les dechets nucleaires acquis et perspectives a l'echeance 2006

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2006-07-01

    The law from December 30, 1991, precisely defines 3 axes of researches for the management of high level and long-lived radioactive wastes: separation/transmutation, surface storage and underground disposal. A global evaluation report about these researches is to be supplied in 2006 by the French government to the Parliament. The responsibility of these researches is given to the French atomic energy commission (CEA) and to the national agency for radioactive wastes (ANDRA) who have to coordinate their works with other research organizations and industrialists. The aim of this colloquium is to make a status of the scientific knowledge gained before the implementation of the public and parliamentary debates on nuclear wastes management. This document gathers the presentations (slides) given at the colloquium and dealing with: separation/transmutation, storage and conditioning of waste packages; geologic disposal, the inter-disciplinary PACE program of the CNRS; synthesis of the researches evaluation process; general principles for a sustainable management of radioactive wastes; technical experience implemented by industrialists since 15 years; point of view of the nuclear safety authority; international context of nuclear waste management and related researches; a sociological enlightening: researches advance as seen by the public. (J.S.)

  5. The sea water desalination by the nuclear reactors; Le dessalement de l'eau de mer par les reacteurs nucleaires

    Energy Technology Data Exchange (ETDEWEB)

    Nisan, S. [CEA Cadarache, Dir. du Developpement et de l' Innovation Nucleares DDIN, 13 - Saint-Paul-lez-Durance (France)

    2002-07-01

    This document underlines the importance of water shortage in many areas in the world in the future. The water sea desalination can be a efficient solution to this problem. The desalination methods are presented. In this context the desalination reactors appear as a competitive solution, facing the fossil energies systems not only for the simultaneous electric power and drinking water production, but also for the minimization of greenhouse gases. (A.L.B.)

  6. Nuclear systems of the future. Stakes, R and D strategy, and international cooperation; Les systemes nucleaires du futur. Enjeux, strategie de recherche et developpement, et cooperation internationale

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2005-07-01

    As demonstrated by prospective studies, nuclear energy will represent a decisive contribution in the future energy mix. The long-term strategy of development of nuclear energy requires to foresee a new generation of nuclear systems, named generation 4. The goal of these new systems is to optimize the use of nuclear fuels, to minimize the generation of wastes and to enlarge the field of applications of nuclear energy to other applications like: hydrogen and synthetic fuels generation, heat generation for the industry etc. This document presents the French R and D strategy on nuclear systems of 4. generation that has been approved by the public authorities. This strategy follows three axes: a priority research on fast neutron systems with fuel recycle (sodium fast reactors (SFR) and gas fast reactors (GFR)), a research on key-technologies for the supply of very high temperature heat (very high temperature reactor (VHTR), fast and thermal neutron reactors, and water decomposition processes), and a continuation of researches on PWR reactors improvement. An integral recycling of all actinides in fast neutron reactors requires the development of new fuel reprocessing and fuel re-fabrication processes. A reference scenario for the progressive renewal of French nuclear facilities foresees the simultaneous development of fast neutron systems and the start-up of a new spent fuel reprocessing plant. France in involved in the development of the SFR, GFR and VHTR systems thanks to its participation to the Generation 4 international forum and to bilateral cooperation with other big nuclear partners like Russia and China. One of the main stakes of the French nuclear industry is to be able to invest in the R and D of future nuclear systems in order to valorize the experience gained so far in sodium FBR systems and in fuel cycle processes. (J.S.)

  7. The today situation and the nuclear sector perspectives in Usa; La situation actuelle et les perspectives du secteur nucleaire aux Etats-Unis

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2006-07-01

    In this analysis the author details and discusses the nuclear energy situation in the Usa: the park and the electric power production, the nuclear safety and the radiation protection, the licenses prolongation, the power increase, the regulation relative to the construction of new reactors, the combined construction permit and operating license, the uncertainties on the Yucca Mountain storage site and the Global Nuclear Energy Partnership initiative, the 2006 perspectives and the IV generation reactors. (A.L.B.)

  8. Integral measurements on Caliban and Prospero assemblies for nuclear data validation; Mesures integrales sur les assemblages Caliban et Prospero pour la validation des donnees nucleaires

    Energy Technology Data Exchange (ETDEWEB)

    Casoli, P.; Authier, N.; Richard, B. [CEA Valduc, 21 - Is-sur-Tille (France); Ducauze-Philippe, M.; Cartier, J. [CEA Bruyeres-le-Chatel, 91 (France)

    2011-07-15

    How can the quality of nuclear data libraries be checked? Performing reference experiments also called benchmarks allows the testing of evaluated data. During these experiments, integral values such as reaction rates or neutron effective multiplication coefficients are measured. In this paper, the principles of benchmark construction are explained and illustrated with several works performed on the CALIBAN et PROSPERO critical assemblies operated by the Valduc center: benchmarks for dosimetry, activation reactions studies, neutron noise measurements. (authors)

  9. Nuclear raw materials. Knowledge status after the Geneva conference (September 1958); Les matieres premieres nucleaires. Etat des connaissances apres la conference de Geneve (Septembre 1958)

    Energy Technology Data Exchange (ETDEWEB)

    Lecoq, M.; Mabile, J. [Direction des Recherches et Exploitations Minieres (France); Carrat, G. [Service Central des Recherches, Direction des Recherches et Exploitations Minieres (France); Ginocchio, A. [Service Central des Productions, Direction des Recherches et Exploitations Minieres (France); Roques, E. [Service Concentration, Direction des Recherches et Exploitations Minieres (France); Waynbaum, M. [Service Developpement et Programmes Generaux, Direction des Recherches et Exploitations Minieres (France); Chervet, J.; Branche, G.; Geffroy, J. [Service de Mineralogie, Centre d' Etudes Nucleaires de Fontenay-aux-Roses (France); Le Goff, M. [Secretariat technique de la Direction des Recherches et Exploitations Minieres (France)

    1959-05-15

    The authors propose a synthesis of the numerous contributions presented at the Geneva conference. They first address deposits: uranium deposits (studies on uranium geochemistry and metallogeny, descriptions of various deposit types such as those associated with sedimentary layers or tectonic structures or petrographic types), thorium deposits, beryllium deposits, zirconium deposits. A second part addresses research methods and equipment: descriptive mineralogical studies, analytic physical or chemical methods, analytic field methods, isotope analysis, prospecting methods (geochemical techniques, radiometry, geophysical methods, general remarks on prospecting methods, organization of prospecting operations, and techniques of deep prospecting). The third part addresses the issues of reserves and resources: definitions, assessment techniques, geographical distribution of reserves and resources. The fourth part addresses the exploitation: quarries, underground exploitation, measures for personnel protection. The fifth part addresses ore concentration: determination of uranium ore and other raw material, concentration by physical means, ore concentration by chemical means, ore sampling, and plant monitoring and regulation. The last part addresses the economy of raw materials: uranium (cost price and production, and purchase and selling prices in different countries, world market in 1960 and on a longer term), thorium, beryllium, zirconium, lithium and helium.

  10. Report on the possibilities of long-term storage of irradiated nuclear fuels; Rapport sur les possibilites d'entreposage a long terme de combustibles nucleaires irradies

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-07-01

    This report aims at giving a legislative aspect to the many rules that govern the activities of the back-end of the fuel cycle in France. These activities concern the unloading of spent nuclear fuels, their reprocessing, storage, recycling and definitive disposal. The following points are reviewed and commented: the management of non-immediately reprocessed fuels (historical reasons of the 'all wastes reprocessing' initial choice, evolution of the economic and political context, the future reprocessing or the definitive disposal of spent fuels in excess); the inevitable long-term storage of part of the spent fuels (quantities and required properties of long-term stored fuels, the eventuality of a definitive disposal of spent fuels); the criteria that long-term storage facilities must fulfill (confinement measures, reversibility, surveillance and control during the whole duration of the storage); storage concept to be retained (increase of storage pools capacity, long-term storage in pools of reprocessing plants, centralized storage in pools, surface dry-storage on power plant sites, reversible underground storage, subsurface storage and storage/disposal in galleries, surface dry-storage facilities); the preliminary studies for the creation of long-term storage facilities (public information, management by a public French organization, clarifying of the conditions of international circulation of spent fuels); problems linked with the presence of foreign spent fuels in France (downstream of the reprocessing cycle, foreign plutonium and wastes re-shipment); conclusions and recommendations. (J.S.)

  11. Production and validation of nuclear data for reactor and fuel cycle applications; Production et validation des donnees nucleaires pour les applications reacteurs et cycle du combustible

    Energy Technology Data Exchange (ETDEWEB)

    Trakas, C [Framatome ANP GmbH NBTT, Erlangen (Germany); Verwaerde, D [Electricite de France EDF, 75 - Paris (France); Toubon, H [Cogema, 78 - Velizy Villacoublay (France); and others

    2002-07-01

    The aim of this technical meeting is the improvement of the existing nuclear data and the production of new data of interest for the upstream and downstream of the fuel cycle (enrichment, fabrication, management, storage, transport, reprocessing), for the industrial reactors, the research reactors and the new reactor concepts (criticality, dimensioning, exploitation), for the instrumentation systems (external and internal sensors), the radioprotection, the residual power, the structures (neutron bombardment effect on vessels, rods etc..), and for the activation of steel structures (Fr, Ni, Co). The expected result is the collection of more reliable and accurate data in a wider spectrum of energies and temperatures thanks to more precise computer codes and measurement techniques. This document brings together the communications presented at this meeting and dealing with: the process of production and validation of nuclear data; the measurement facilities and the big international programs; the users needs and the industrial priorities; the basic nuclear data (BND) needs at Cogema; the expression and evaluation of BND; the evaluation work: the efficient cross-sections; the processing of data and the creation of activation libraries; from the integral measurement to the qualification and the feedback on nuclear data. (J.S.)

  12. Present day situation and perspectives of the nuclear sector in the USA; La situation actuelle et les perspectives du secteur nucleaire aux Etats-Unis

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2008-07-01

    With the restart-up of Browns Ferry NPP on May 22, 2007, the US nuclear park comprises now 104 reactors in operation: 35 BWR-type and 69 PWR-type. NPPs are present in only 31 states and mainly in the eastern half of the country. Nuclear energy represents 20% of the US energy mix (coal: 50%, gas: 19%, hydro-power: 6%, petroleum: 3% and other renewable energies: 2%). The highest average availability rate in power generation is reached by nuclear energy (89.9%). The nuclear power generation reached 787.2 TWh in 2006, i.e. the second best result after the 2004 record (788.5 TWh). This document presents also some nuclear safety and radioprotection indicators (number of unplanned outages, failures, injury frequency rate), the programme of licenses extension, the permissions for power increase, the demands for design certification, for early site permit, and for combined construction permit and operating license. The regulation may be different from one state to the other and sometimes not favorable to a re-launch of nuclear energy. The situation of each state in this domain is presented in appendix. (J.S.)

  13. Problems bound to the tritium in materials for the nuclear - some illustrations; Problematiques liees au tritium dans les materiaux dans le domaine nucleaire - quelques illustrations

    Energy Technology Data Exchange (ETDEWEB)

    Gastaldi, O. [CEA Cadarache (DTN/STPA/LPC), 13 - Saint-Paul-lez-Durance (France)

    2007-07-01

    The tritium control takes more and more importance in the nuclear industry because of the release more and more limited, in the environment. After a presentation on the tritium sources in the environment, the author presents the different ways of its production. Then for each reactor channel, the main problems are presented (fission and fusion). The last part deals with the behavior of the tritium in materials: the tritium inventory control in a fusion system, the tritium management after the reactor exploitation. (A.L.B.)

  14. The decommissioning of nuclear facilities; Le demantelement des installations nucleaires de base

    Energy Technology Data Exchange (ETDEWEB)

    Niel, J.Ch.; Rieu, J.; Lareynie, O.; Delrive, L.; Vallet, J.; Girard, A.; Duthe, M.; Lecomte, C.; Rozain, J.P.; Nokhamzon, J.G.; Davoust, M.; Eyraud, J.L.; Bernet, Ph.; Velon, M.; Gay, A.; Charles, Th.; Leschaeva, M.; Dutzer, M.; Maocec, Ch.; Gillet, G.; Brut, F.; Dieulot, M.; Thuillier, D.; Tournebize, F.; Fontaine, V.; Goursaud, V.; Birot, M.; Le Bourdonnec, Th.; Batandjieva, B.; Theis, St.; Walker, St.; Rosett, M.; Cameron, C.; Boyd, A.; Aguilar, M.; Brownell, H.; Manson, P.; Walthery, R.; Wan Laer, W.; Lewandowski, P.; Dorms, B.; Reusen, N.; Bardelay, J.; Damette, G.; Francois, P.; Eimer, M.; Tadjeddine, A.; Sene, M.; Sene, R

    2008-11-15

    ,; the fifth part presents the external points of view on dismantling with: the decommissioning of Saint-Laurent A, as seen by the local information committee, decommissioning: the urge for a public consultation, an evaluation of the work of the 'conseil superieur de la surete et de linformation nucleaire' (C.S.S.I.N.) - a consultative body dealing with information in the field of nuclear safety) on the issue of decommissioning basic nuclear installations, monitoring the decommissioning of nuclear facilities and examining applications. (N.C.)

  15. Economic consequences of the Swiss 'Sortir du nucleaire' and 'Moratoire-plus' popular initiatives - Analysis using a balanced model

    International Nuclear Information System (INIS)

    Mueller, A.; Wickart, M.; Van Nieuwkoop, R.

    2001-01-01

    This article is a short version of the ENET number 210359. This report for the Swiss Federal Office of Energy (SFOE) presents the results of a study made to assess the economic consequences of two models for the opting out of nuclear energy in Switzerland, as proposed in two popular initiatives. The 'Sortir du nucleaire' (electricity without atomic power) initiative calls for the shutting down of the existing nuclear power stations and the 'Moratoire-plus' initiative calls for a stop on the building of new atomic power stations for 10 years. The method used for assessing the costs and benefits resulting if the initiatives were accepted in a public vote is described. Basic assumptions made on further factors concerning the electricity and energy markets are discussed. Results of analyses made for various scenarios with respect to CO 2 emissions are presented and include discussions on risk costs, effects on employment and welfare aspects

  16. Dosimeter calibration facilities and methods at the Radiation Measurement Laboratory of the Centre d'etudes nucleaires, Grenoble

    International Nuclear Information System (INIS)

    Choudens, H. de; Herbaut, Y.; Haddad, A.; Giroux, J.; Rouillon, J.; CEA Centre d'Etudes Nucleaires de Grenoble, 38

    1975-01-01

    At the Centre d'etudes nucleaires, Grenoble, the Radiation Measurement Laboratory, which forms part of the Environmental Protection and Research Department, serves the entire Centre for purposes of dosimetry and the calibration of dose meters. The needs of radiation protection are such that one must have facilities for checking periodically the calibration of radiation-monitoring instruments and developing special dosimetry techniques. It was thought a good idea to arrange for the dosimetry and radiation protection team to assist other groups working at the Centre - in particular, the staff of the biology and radiobiology laboratories - and also bodies outside the framework of the French Commissariat a l'energie atomique. Thus, technical collaboration has been established with, for example, Grenoble's Centre hospitalier universitaire (university clinic), which makes use of the facilities and skills available at the Radiation Measurement Laboratory for solving special dosimetry problems. With the Laboratory's facilities it is possible to calibrate dose meters for gamma, beta and neutron measurements

  17. Communiquer ! les bibliothécaires, les décideurs et les journalistes

    CERN Document Server

    2010-01-01

    L'enjeu de la communication en direction des élus, des décideurs, mais aussi des journalistes, est devenu vital pour les bibliothèques : il s'agit de donner à voir aux tutelles leurs activités, de rendre intelligible leur stratégie de développement, de construire une image institutionnelle forte. De quels moyens dispose la bibliothèque pour faire la preuve du bien-fondé de son existence ? Comment communiquer en direction d'un élu municipal ou régional, d'un responsable politique de la bibliothèque ? Que peut apporter une bonne collaboration avec des journalistes, avec les partenaires naturels ou hiérarchiques au sein de l'université ou de la collectivité territoriale ? Comment utiliser à bon escient les méthodes du lobbying et du marketing, ou l'emploi des réseaux sociaux ? Voilà quelques-unes des questions abordées ici.

  18. Experimental Study of the Process of Neutron Thermalization in Time in Aqueous Moderators; Etude Experimentale du Processus de Thermalisation des Neutrons en Fonction du Temps dans les Ralentisseurs Contenant de l'Eau; Ehksperimental'noe izuchenie protsessa termalizatsii nejtronov vo vremeni v vodorodosoderzhashchikh zamedlitelyakh; Estudio Experimental del Proceso de Termalizacion de Neutrones en Funcion del Tiempo en Moderadores Acuosos

    Energy Technology Data Exchange (ETDEWEB)

    Ishmaev, S. N.; Mostovoj, V. I.; Sadikov, I. P.; Chernyshov, A. A. [Gosudarstvennyj Komitet po Ispol' zovaniju Atomnoj Ehnergii SSSR, Institut Atomnoj Ehnergii Im. I.V.Kurchatova, Moskva, SSSR (Russian Federation)

    1965-08-15

    Using a method described in another paper presented at this Symposium, the authors measured non-stationary neutron spectra in zirconium hydride and in water at room temperature as a function of slowing-down time, with a resolution of 3.5 {mu}s. The spectra measured in a large ZrH prism (B{sup 2} = 3.8 x 10{sup -2} cm{sup 2}) belong to a slowing-down time range (t > 30 {mu}s) in which the mean neutron energy is less than 0.13 eV and the energy exchange between neutron gas and the medium is caused mainly by the excitation of acoustic lattice vibrations. In this range thermalization proceeds at a comparatively slow rate and the time required to establish an equilibrium neutron spectrum is of the order of 400 {mu}s. In a small ZrH assembly (B{sup 2} Asymptotically-Equal-To 20 x 10{sup -2} cm{sup 2}) a strong diffusion-cooling effect is observed. The spectra measured at long slowing-down times are found to differ considerably from the Maxwellian distribution with the temperature of the medium. The time required to establish an equilibrium energy distribution increases with decreasing system size. The neutron energy spectra in water (B{sup 2} = 2.56 x 10{sup -2}cm{sup 2}) are presented for slowing-down times of over 13 {mu}s, where distortions from resolution are insignificant. The shape of the spectrum is only fully consistent with the Maxwellian distribution at room temperature after about 100 {mu}s following a fast neutron burst. The time required to establish an equilibrium neutron spectrum in this experiment is three to four times longer than the values calculated by various other authors. The possible reasons for this discrepancy are discussed. (author) [French] A l'aide de la methode que les auteurs ont decrite dans un autre memoire presente au Colloque, ils ont mesure, en fonction du temps de ralentissement, les spectres non stationnaires des neutrons dans l'hydrure de zirconium et dans l'eau a la temperature ambiante, avec un pouvoir de resolution de 3,5 {mu

  19. Experimental animal studies of radon and cigarette smoke

    International Nuclear Information System (INIS)

    Cross, F.T.; Dagle, G.E.; Gies, R.A.; Smith, L.G.; Buschbom, R.L.

    1992-01-01

    Cigarette-smoking is a dominant cause of lung cancer and confounds risk assessment of exposure to radon decay products. Evidence in humans on the interaction between cigarette-smoking and exposure to radon decay products, although limited, indicates a possible synergy. Experimental animal data, in addition to showing synergy, also show a decrease or no change in risk with added cigarette-smoke exposures. This article reviews previous animal data developed at Compagnie Generale des Matieres Nucleaires and Pacific Northwest Laboratory (PNL) on mixed exposures to radon and cigarette smoke, and highlights new initiation-promotion-initiation (IPI) studies at PNL that were designed within the framework of a two-mutation carcinogenesis model. Also presented are the PNL exposure system, experimental protocols, dosimetry, and biological data observed to date in IPI animals

  20. An experimental study on mineral sequestration of CO{sub 2} in basics and ultra basics rocks; Etude experimentale des reactions de carbonatation minerale du CO{sub 2} dans les roches basiques et ultrabasiques

    Energy Technology Data Exchange (ETDEWEB)

    Dufaud, F

    2006-11-15

    The first part of the thesis is dedicated to dissolution data of siderite FeCO{sub 3} and magnetite Fe{sub 3}O{sub 4} which have been monitored in situ on the FAME beamline of the european synchrotron radiation facility in Grenoble. Iron in solution close to siderite single crystals is shown to be divalent hydrated. The small size of the experimentally investigated volume of solution (200 *400 micrometer and 3 mm height) allowed to work with single crystals in well defined geometries. No specific interaction was observed between iron (II) and dissolved inorganic carbon, suggesting that modelling siderite evolution under high CO{sub 2} pressures by using CO{sub 2}-less very acidic (pH 1-2) solutions is adequate. Using initial reaction rates, we get an activation energy for siderite dissolution of 62 kJ.mol{sup -1}, consistent with existing literature data. Such a value is suggestive of a mineral/solution interface mechanism.. Data from this study and from literature are consistent over a temperature range 25 C - 125 C and a pH range pH 1-7 with an empirical law: pk = pH + E{sub a}/(ln(10)*RT(K)) - log(S/V) - 10,5 where E{sub a} = 62 kJ.mol{sup -1} and S/V is the ratio between solid surface S and fluid volume V. A value of activation energy of 73.5 kJ.mol{sup -1} is obtained in the case of magnetite, also consistent with mineral/solution processes. The second and major part of the thesis work is the realization of analogical experiments for simulating carbonation of basic and ultra basic minerals. Experiments were carried out on consolidated rock cores at 90 C and 280 bar of CO{sub 2} (low temperature experiments) and on powders contained in metallic capsules at 400-500 C and 1000-1700 bars of CO{sub 2} (high temperature experiments). The rate of mineral storage of CO{sub 2} was defined as the molar ratio of solid carbonate formed over total CO{sub 2} injected. It is of about 1% in three months in low temperature experiments whereas it reaches several tens of

  1. Le Pétrole et les dispersants dans les mers baignant le littoral canadien: évaluation des recherches et recommandations

    National Research Council Canada - National Science Library

    Sprague, John B; Vandermeulen, J. H; Wells, P. G; Birchard, E. C

    1982-01-01

    ...; les methodes d'analyse; les effets du petrole, des dispersants et du petrole disperse chimiquement sur le phytoplancton, les macrophytes, le zooplancton, les poissons, les organismes et animaux benthiques et intertidaux, les oiseaux, les mammiferes marins, les communautes et les ecosystemes. Il comporte certaines recommandations en vue de recherches futures indispensables et donne des conseils sur la facon de minimiser les effets de deversements de petrole dans le milieu marin canadien.

  2. Les non-usages des TIC

    OpenAIRE

    Abid-Zarrouk, Sandoss Ben; Alava, Séraphin; Andrieu, Bernard; Audran, Jacques; Avanzini, Guy; Azzimani, Toufik; Béziat, Jacques; Bouamri, Abderrahmane; Boujelbène, Younes; Bréant, Françoise; Chauvel, Séverine; Daguet, Hervé; Daniel, Marie-France; Dessus, Philippe; Dupré, Damien

    2012-01-01

    Les ENT (Environnements Numériques de Travail), les plates formes d'EAD (Enseignement A Distance) et les logiciels éducatifs sont généralement étudiés dans la perspective de rendre compte des transformations des situations d'enseignement-apprentissage dans lequelles ils sont utilisés. Les recherches occultent ainsi, de façon non intentionnelle, tout ce qui reste dans l'ombre de l'introduction désormais massive des TIC (Technologies de l'Information et de la Communication), et qui explique pro...

  3. Vitaminothérapie chez les volailles

    OpenAIRE

    Duchadeau, Cécile

    2001-01-01

    La distribution de vitamines dans les élevages aviaires est de plus en plus fréquente, voire systématique, alors qu'elle n'est pas toujours nécessaire ni sans risque ; l'utilisation des vitamines devrait donc être raisonnée. L'étude bibliographique de la structure et des modes d'action de chaque vitamine permet de définir les principales circonstances d'apparition des carences vitaminiques, ainsi que les symptômes susceptibles de se développer. Les carences en vitamines hydrosolubles (C, B1, ...

  4. Large Eddy Simulation (LES for IC Engine Flows

    Directory of Open Access Journals (Sweden)

    Kuo Tang-Wei

    2013-10-01

    Full Text Available Numerical computations are carried out using an engineering-level Large Eddy Simulation (LES model that is provided by a commercial CFD code CONVERGE. The analytical framework and experimental setup consist of a single cylinder engine with Transparent Combustion Chamber (TCC under motored conditions. A rigorous working procedure for comparing and analyzing the results from simulation and high speed Particle Image Velocimetry (PIV experiments is documented in this work. The following aspects of LES are analyzed using this procedure: number of cycles required for convergence with adequate accuracy; effect of mesh size, time step, sub-grid-scale (SGS turbulence models and boundary condition treatments; application of the proper orthogonal decomposition (POD technique.

  5. Chronic myocardial damage in experimental T. cruzi infection of a new world primate, Cebus sp. monkey Lesões miocárdicas crônicas na infecção experimental pelo T. cruzi no macaco (Cebus apella

    Directory of Open Access Journals (Sweden)

    Carlos Alberto Falasca

    1990-06-01

    áficos foram anteriormente publicados15 e são semelhantes àqueles vistos no homem. O achado eletrocardiográfico mais freqüente foi o bloqueio do ramo direito. Seis animais, escolhidos ao acaso, foram sacrificados. Aqueles sacrificados 20 a 25 meses após a primeira inoculação mostraram acúmulos focais de leucócitos com miocitólise. Focos de fibrose intersticial difusa com pequeno infiltrado de leucócitos entre as fibras foram observados em animais sacrificados 36 a 47 meses após a inoculação. Não foram encontrados parasitas. As lesões foram mais proeminentes nas paredes ventriculares e no septo. O achado de infiltrados predominantemente, nos animais sacrificados em tempo mais curto em relação à primeira inoculação e a fibrose mais severa naqueles sacrificados após um tempo maior sugere que existe uma progressão das lesões infiltrativas até a fibrose, com atividade leucocítica indicativa de fase crônica. Estas lesões são semelhantes àquelas descritas na doença de Chagas crônica humana. Este modelo, portanto, é útil na avaliação do progresso e conhecimento da patogênese da doença, assim como de sua imunologia, imunogenesis e da ação da quimioterapia, tanto na sua fase crônica como indeterminada.

  6. Les AOC dans la mondialisation

    Directory of Open Access Journals (Sweden)

    Jean-Claude Hinnewinkel

    2004-12-01

    Full Text Available Fruit du conflit plusieurs fois séculaire entre les producteurs et le négoce, le terroir vitivinicole est né de phénomènes de « distinction » qui en Bordelais donnent les « crus ». Ces terroirs de production identifiés, il fallut les faire durer, face à conjoncture, face au négoce. Les réussites les plus nettes sont le résultat d’un projet collectif dont l’AOC à la française est l’une des plus spectaculaires. Renforcer le terroir, compris comme un espace de production géré par les producteurs, devient alors une des conditions essentielles de la durabilité du système. L’avenir des AOC réside sans doute dans une meilleure gestion du conflit négoce/production par l’interprofession mais aussi (surtout ! dans un renforcement de la gestion de la production au sein de l’aire de production qu’est le terroir. L’avenir du terroir relève de la gouvernance de cette aire de production avec trois partenaires : la puissance publique (INAO, l’interprofession et le syndicat des producteurs. Se pose dès lors la question du partage des compétences et la durabilité des AOC paraît liée en grande partie à une définition claire du rôle et donc du statut des syndicats de producteurs, à une véritable gouvernance locale, seule capable de donner du sens à l’ancrage géographique des vins dits de « terroir ». Mais alors ne faut-il pas impliquer un troisième partenaire, la société locale toute entière à travers ses représentations démocratique et associative ?Resulting from century-long conflicts between producers and merchants, vineyards have developped out of "distinction" phenomenons which in the Bordeaux region gave birth to "crus" (vintages. Such identified terroirs had to be defended: the French collective AOC (Denomination of Origin project is one of the most spectacular success. The terroir, as production territory organized by producers, is one of the essential conditions for sustainability

  7. Aldicarbe et crimidine dans les eaux et les sédiments aux alentours ...

    African Journals Online (AJOL)

    homme et de l'environnement, sont utilisées contre les pestes et autres nuisibles. Cependant, la plupart des études menées se sont focalisées sur les organochlorés. La fréquence de détection et les concentrations des pesticides aldicarbe et ...

  8. Les tribunaux, et non pas les liens de parenté, offrent de meilleures ...

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

    29 janv. 2018 ... Les recherches menées au Bangladesh et en Inde ont révélé que les femmes et les personnes provenant de populations marginalisées ont besoin de tribunaux qui fonctionnent bien pour exploiter leur plein potentiel.

  9. De meilleures données probantes sur les dons privés dans les ...

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

    ... mesurer l'ampleur, les sources et les réussites de la philanthropie ainsi que les facteurs qui la favorisent. ... et futures grâce à son vaste réseau de partenaires individuels et institutionnels. ... Framework Agreement between IISD and IDRC.

  10. The use of an experimental device for disposal into the ground at the Centre d'Etudes Nucleaires at Saclay

    International Nuclear Information System (INIS)

    Amavis, R.; Vaccarezza, J.

    1960-01-01

    This report presents the results of the 3 H and 90 Sr percolation tests carried out with Saclay soil, both in the laboratory in the ground itself. The extrapolation using the parameters introduced by Hiester and Vermeulen, as well as by W.J. Kaufman, appear satisfactory when the soil sample is homogeneous. (author) [fr

  11. Les écoulements fluviaux

    Directory of Open Access Journals (Sweden)

    Huguette VIVIAN

    1992-06-01

    Full Text Available Cette carte présente une image des principaux fleuves et de leurs affluents, ainsi que la situation des principales stations de mesure et des lames d’eau écoulées. Cette mesure des écoulements fluviaux, effectuée d’abord à l’aide des débits mesurés dans 400 stations hydrométriques choisies parmi les 800 du réseau national, a été éventuellement enrichie par des informations complémentaires.

  12. Protection contre les radiations recommandations

    CERN Document Server

    Claude, A; Kipfer, P; Bacq, Z

    Considérations générales ; mesures de sécurité vis-à-vis des sources de rayonnement externes ; mesures de sécurité vis-à-vis des radioisotopes ; étude spéciale de la protection dans quelques cas particuliers ; mesures de sécurité vis-à-vis des neutrons ; mesures de protection pour les appareils de supervoltage ; appareils physiques de mesure et de contrôle pour la protection.

  13. The Why and How of Nuclear Accident Dosimetry; Dosimetrie en cas d'Accident Nucleaire: Raison d'Etre et Modalites; 041e 0411 041e 0421 041d 041e 0412 0414 ; Dosimetria en Casos de Accidente Nuclear: Justificacion y Modalidades

    Energy Technology Data Exchange (ETDEWEB)

    Vallario, E. J.; Wasson, H. R. [United States Atomic Energy Commission, Washington, DC (United States)

    1965-06-15

    The objective of an effective nuclear accident dosimetry programme is to ensure that a means is provided for estimating the gamma neutron dose from a nuclear accident. In this connection, the limitation of the film badge is discussed, in addition to certain accident experiences which demonstrate the need for an effective accident dosimetry programme at facilities having a potential for nuclear accidents. Certain basic parameters should be considered in the development of an effective nuclear accident dosimetry programme. These are (a) a method for screening personnel involved in nuclear accidents, (b) a fixed system (primary unit) capable of determining first collision dose within some established degree of accuracy at its point of location, (c) the need for ''secondary units'', and (d) the need for a device worn by personnel which would afford spectrum and flux information to assist in dose extrapolation from the fixed unit to the location of man. The neutron component of the system should permit flux and spectral information in order to arrive at appropriate quality factors in the dose estimation. Accuracies should be established based upon the current state of the art. The gamma -ray component of the system should permit measuring gamma radiation within the biological area of interest, i. e. from 10 to 10{sup 3}r. Consideration for the number, placement and ease of recovery of accident units are indeed an integral part of an effective system of accident dosimetry. These considerations should enable reasonable data collection across the entire fission spectrum. (author) [French] L'objet d'un programme efficace de dosimetrie en cas d'accident nucleaire est d'evaluer la dose de rayons gamma et de neutrons emise lors d'un acccident nucleaire. Le memoire examine les limitations des dosimetres a film et expose les circonstances accompagnant certains accidents, lesquelles demontrent la necessite de prevoir un programme efficace de dosimetrie dans les installations ou

  14. Physics experiments in graphite lattices (1962); Experiences sur les reseaux a graphite (1962)

    Energy Technology Data Exchange (ETDEWEB)

    Bacher, P; Cogne, F [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1962-07-01

    A review is made of the various experimental methods used to determine the physics of graphite, natural uranium lattices: integral lattice experiments; both absolute and differential, effective cross section measurements, both by activation methods and by analysis of irradiated fuels, fine structure measurements. A number of experimental results are also given. (authors) [French] On decrit les differentes methodes experimentales utilisees pour determiner les parametres physiques de reseaux a uranium-graphite. Il s'agit d'experiences globales: mesures absolues et relatives de laplaciens, mesures de sections efficaces effectives par activation et par analyses de combustibles irradies, mesures de structures fines. Un certain nombre de resultats experimentaux sont communiques. (auteurs)

  15. Adaptation dans les zones cruciales au regard des changements ...

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

    ) vise à accroître la résilience des populations pauvres dans trois « zones cruciales » au regard des changements climatiques : les bassins hydrographiques, les deltas et les régions semi-arides.

  16. Comment scolariser les enfants Roms? Les enfants Roms dans les dispositifs mis en place à Bordeaux Métropole.

    OpenAIRE

    Øhlund, Ida

    2016-01-01

    Dans ce mémoire, je m intéresse à la scolarisation des enfants Roms en France. Je présente la place des enfants Roms dans la scolarisation en Europe et en France. Je discute les efforts qu on fait en France pour scolariser ces enfants, et je prends comme exemple les mesures d intégration prises par les autorités de Bordeaux Métropole en expliquant lesles des différents acteurs locaux. Dans la première partie, j essaye de présenter le groupe minoritaire européen appelé « Rom ». J aborde l h...

  17. Influência do tempo transcorrido entre a lesão do cólon e a síntese no processo de cicatrização Influence of running time between colon injury and repair in the healing process: experimental study in rats

    Directory of Open Access Journals (Sweden)

    Maria de Lourdes Pessole Biondo-Simões

    2000-01-01

    Full Text Available O tratamento das lesões do cólon têm se modificado com relação à escolha da técnica do reparo primário à colostomia e ao reparo secundário. Entre os fatores de risco para síntese primária está o tempo transcorrido. O objetivo deste estudo é avaliar as interferências do tempo transcorrido entre a feitura da lesão e a síntese, sobre o processo de cicatrização. Para isto utilizaram-se 80 ratos Wistar PUC-PR. Sob anestesia inalatória confeccionou-se uma lesão no cólon esquerdo compromentendo 50% da circunferência da intestinal. Após 12, 18 e 24 horas procedeu-se à síntese. Comparou-se estas colorrafias com as realizadas imediatamente após a lesão. Avaliaram-se as cicatrizes com 4 e 7 dias, verificando-se a existência de deiscências, a capacidade de suportar pressão e a síntese de colágeno. Registrou-se o óbito de 5 ratos. Encontrou-se peritonites nos 3 grupos de experimento que comparadas ao controle mostraram alta significância, para o grupo B (p=0,0018, para o C (p=0,0033 e para o D (p=0,000008q Deiscências se fizeram presentes 19 vezes, tendo sido significante no grupo de 24 horas (p=0,000002. A quantidade de colágeno maturo (tipo I, no 4.º dia é semelhante ao controle no grupo de 12 e 18 horas e menor no grupo de 24 horas (pThe treatment of colonic lesions has been modified regarding the choice of primary repair technique, colostomy and secondary repair. Among risk factors for primary repair is time lapse. The aim of the present study was to evaluate the role of the time span between the induced lesion and surgical repair, regarding wound healing. Eighty PUC-PR Wistar rats were used for this purpose. Under ether anesthesia a lesion in the left colon was made, affecting 50% of the circumference of the intestine. After 12, 18 and 24 hours the repair was done. The colonic repairs were compared to the those made immediately after the lesion. Wounds were evaluated on the 4th and 7th post-operative days and the

  18. Les supraconducteurs en courant alternatif

    Science.gov (United States)

    Lacaze, A.; Laumond, Y.

    1991-02-01

    Since 1983, when the very first AC wire became available, the comprehension of electromagnetic phenomenas ruling over stability and losses of multifilamentary superconductors in AC use, has much improved. Improvements of manufacturing process has opened up the possibility of industrial scale manufacturing of up to one million, 140 nm in diameter, filaments. The AC loss performances and stability remains at the best level up to date. Les premiers brins supraconducteurs utilisables en courants alternatifs sont apparus en 1983. Depuis, des progrès importants ont été réalisés sur le plan de la compréhension des phénomènes électromagnétiques commandant les pertes et la stabilité dans des brins multifilamentaires à filaments ultrafins. L'amélioration des performances et des procédés de fabrication nous permet aujourd'hui de présenter des brins, fabriqués à l'échelle industrielle, comprenant jusqu'à près d'un million de filaments de 140 nm de diamètre, avec des niveaux de pertes et de stabilité inégalés à ce jour.

  19. Les parcs des porcelainiers Haviland

    Directory of Open Access Journals (Sweden)

    Colette Chabrely

    2012-04-01

    Full Text Available Les parcs du Reynou et de Mont-Méry en Limousin, anciennes propriétés des porcelainiers Haviland, présentent l’un et l’autre un grand intérêt paysager et botanique. Dans les deux cas, l’attribution de la création est incertaine. Cet article propose pour le Reynou une analyse de documents figurés anciens permettant de préciser la chronologie des travaux du château et du parc. Pour Mont-Méry il s’agit de poser de nouveaux jalons pour une étude plus approfondie des sources et de la composition des jardins afin d’envisager de nouvelles pistes pour leur attribution.The Reynou and Mont-Méry parks near Limoges originally belonged to the city’s porcelain manufacturers, the Havilands. Both parks are of considerable interest in terms of their landscaping and their botany. In both cases, there is some uncertainty as to the identity of their designers. This article offers an analysis of the graphic representations of the Reynou park, clarifying the chronology of the creation of the château and its park. For the Mont-Méry park, the aim is to offer some guidelines for further research in the source material and on the design of the park itself, perhaps allowing for the designer to be identified.

  20. Inquiétudes pour les emplois

    CERN Multimedia

    2002-01-01

    "Le dépassement budgétaire du LHC oblige la direction a réaliser des économies. Selon les syndicats francais et suisses, ces économies entraineraient des suppressions d'emplois, notamment chez les enterprises sous-traitantes du Cern"

  1. Les faits,une arme contre

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

    un_focus_pauvreté. Aux Philippines, les progrès reposent sur une information rigoureuse. Aux Philippines, le système de suivi communautaire de la pauvreté, d'abord projet pilote, s'est étendu, en 14 ans, à l'échelle nationale, appuyé par tous les ordres ...

  2. les cahiers du cread: About this journal

    African Journals Online (AJOL)

    les cahiers du cread: About this journal. Journal Home > les cahiers du cread: About this journal. Log in or Register to get access to full text downloads. Username, Password, Remember me, or Register · Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current Issue · Archives. People. » Contact. Policies.

  3. New Frontiers for Non-Destructive Testing in the Nuclear Age; Perspectives des Essais Non Destructifs a l'Ere Nucleaire; ''Novye rubezhi'' nedestruktivnykh ispytanij v yadernyj vek; Nuevas Posibilidades de los Ensayos No Destructivos en la Era Nuclear

    Energy Technology Data Exchange (ETDEWEB)

    Ballard, D. W. [Sandia Laboratory Albuquerque, NM (United States)

    1965-10-15

    suitable for remote television displays and recording. Test parameters, display capabilities, and continuous monitoring systems are discussed. These possibilities have. already been demonstrated in laboratory testing and their use must be extended to production testing if a new level of reliability of components in the nuclear industry is to be achieved. (author) [French] On peut attribuer en grande partie l'extraordinaire developpement des essais non destructifs depuis la deuxieme guerre mondiale aux specifications extremement strictes imposees aux materiaux et produits de l'industrie nucleaire. La complexite des installations et de leurs elements et les incidences financieres des arrets de fonctionnement ont atteint des proportions telles qu'il est imperieux de mettre au point des methodes plus efficaces d'essais non destructifs et de les appliquer tout au long de la duree de vie des produits, depuis leur mise en fabrication jusqu'a leur declassement. En meme temps que, pour tenter de satisfaire aux imperatifs techniques de perfection, on developpe considerablement les possibilites offertes par des methodes d'essais confirmees, comme la radiographie, les ultrasons et l'electromagnetisme, on met au point de nouveaux principes d'essais destines expressement au controle des performances statiques et dynamiques. Le memoire porte sur ces methodes particulierement rapides et sensibles qui ouvrent vraiment de nouvelles perspectives aux essais non destructifs. Au nombre des methodes d'essais les plus recentes discutees dans le memoire figure le controle par les infra- rouges de l'integrite des soudures. Le controle cineradiographique des structures au cours des essais de vibration, pour etudier leur comportement dynamique, est egalement traite. La detection des fuites est extremement importante pour assurer la qualite des elements combustibles. Le memoire decrit une methode de controle des elements combustibles sous gaine, qui est fondee sur l'utilisation d'un gaz radioactif et

  4. N° 341-Diagnostic et prise en charge de la torsion annexielle chez les filles, les adolescentes et les femmes adultes.

    Science.gov (United States)

    Kives, Sari; Gascon, Suzy; Dubuc, Élise; Van Eyk, Nancy

    2017-02-01

    Passer en revue les connaissances scientifiques actuelles et formuler des recommandations relatives au diagnostic et à la prise en charge de la torsion annexielle chez les filles, les adolescentes et les femmes adultes. L'étude porte sur les facteurs de risque, la précision diagnostique, les options de prise en cha