WorldWideScience

Sample records for developpement des methodes

  1. Developpement d'une methode calorimetrique de mesure des pertes ac pour des rubans supraconducteurs a haute temperature critique

    Science.gov (United States)

    Dolez, Patricia

    Le travail de recherche effectue dans le cadre de ce projet de doctorat a permis la mise au point d'une methode de mesure des pertes ac destinee a l'etude des supraconducteurs a haute temperature critique. Pour le choix des principes de cette methode, nous nous sommes inspires de travaux anterieurs realises sur les supraconducteurs conventionnels, afin de proposer une alternative a la technique electrique, presentant lors du debut de cette these des problemes lies a la variation du resultat des mesures selon la position des contacts de tension sur la surface de l'echantillon, et de pouvoir mesurer les pertes ac dans des conditions simulant la realite des futures applications industrielles des rubans supraconducteurs: en particulier, cette methode utilise la technique calorimetrique, associee a une calibration simultanee et in situ. La validite de la methode a ete verifiee de maniere theorique et experimentale: d'une part, des mesures ont ete realisees sur des echantillons de Bi-2223 recouverts d'argent ou d'alliage d'argent-or et comparees avec les predictions theoriques donnees par Norris, nous indiquant la nature majoritairement hysteretique des pertes ac dans nos echantillons; d'autre part, une mesure electrique a ete realisee in situ dont les resultats correspondent parfaitement a ceux donnes par notre methode calorimetrique. Par ailleurs, nous avons compare la dependance en courant et en frequence des pertes ac d'un echantillon avant et apres qu'il ait ete endommage. Ces mesures semblent indiquer une relation entre la valeur du coefficient de la loi de puissance modelisant la dependance des pertes avec le courant, et les inhomogeneites longitudinales du courant critique induites par l'endommagement. De plus, la variation en frequence montre qu'au niveau des grosses fractures transverses creees par l'endommagement dans le coeur supraconducteur, le courant se partage localement de maniere a peu pres equivalente entre les quelques grains de matiere

  2. Developpement d'un modele analytique pour l'analyse en elasticite lineaire de champs de deformation et contrainte au sein d'un polycristal. comparaison avec la methode des elements finis =

    Science.gov (United States)

    Bretin, Remy

    L'endommagement par fatigue des materiaux est un probleme courant dans de nombreux domaines, dont celui de l'aeronautique. Afin de prevenir la rupture par fatigue des materiaux il est necessaire de determiner leur duree de vie en fatigue. Malheureusement, dues aux nombreuses heterogeneites presentes, la duree de vie en fatigue peut fortement varier entre deux pieces identiques faites dans le meme materiau ayant subi les memes traitements. Il est donc necessaire de considerer ces heterogeneites dans nos modeles afin d'avoir une meilleure estimation de la duree de vie des materiaux. Comme premiere etape vers une meilleure consideration des heterogeneites dans nos modeles, une etude en elasticite lineaire de l'influence des orientations cristallographiques sur les champs de deformations et de contraintes dans un polycristal a ete realisee a l'aide de la methode des elements finis. Des correlations ont pu etre etablies a partir des resultats obtenus, et un modele analytique en elasticite lineaire prenant en compte les distributions d'orientations cristallographiques et les effets de voisinage a pu etre developpe. Ce modele repose sur les bases des modeles d'homogeneisation classique, comme le schema auto-coherent, et reprend aussi les principes de voisinage des automates cellulaires. En prenant pour reference les resultats des analyses elements finis, le modele analytique ici developpe a montre avoir une precision deux fois plus grande que le modele auto-coherent, quel que soit le materiau etudie.

  3. Contribution au developpement d'une methode de controle des procedes dans une usine de bouletage

    Science.gov (United States)

    Gosselin, Claude

    overall (economic) satisfaction in the production process, but rather in proposing it as an "observer" of the system's state. The first implementation steps have already demonstrated the method's feasibility as well as other numerous industrial impacts on production processes within the company. Namely, the emergence of the economical aspect as a strategic variable that assures better governance of production processes where quality variables present strategic issues.

  4. Development op finite volume methods for fluid dynamics; Developpement de methodes de volumes finis pour la mecanique des fluides

    Energy Technology Data Exchange (ETDEWEB)

    Delcourte, S

    2007-09-15

    We aim to develop a finite volume method which applies to a greater class of meshes than other finite volume methods, restricted by orthogonality constraints. We build discrete differential operators over the three staggered tessellations needed for the construction of the method. These operators verify some analogous properties to those of the continuous operators. At first, the method is applied to the Div-Curl problem, which can be viewed as a building block of the Stokes problem. Then, the Stokes problem is dealt with with various boundary conditions. It is well known that when the computational domain is polygonal and non-convex, the order of convergence of numerical methods is deteriorated. Consequently, we have studied how an appropriate local refinement is able to restore the optimal order of convergence for the Laplacian problem. At last, we have discretized the non-linear Navier-Stokes problem, using the rotational formulation of the convection term, associated to the Bernoulli pressure. With an iterative algorithm, we are led to solve a saddle-point problem at each iteration. We give a particular interest to this linear problem by testing some pre-conditioners issued from finite elements, which we adapt to our method. Each problem is illustrated by numerical results on arbitrary meshes, such as strongly non-conforming meshes. (author)

  5. Amenagements sportifs et developpement durable : Des enjeux ...

    African Journals Online (AJOL)

    ... contredite » éprouvée par (Jeu, 1977), comme l'apanage d'une double hybridation culturelle des pays en développement. Derrière l'apparence de la dislocation des héritages, doit émerger une définition nouvelle sur les rapports que les sports devraient entretenir avec l'environnement pour un développement durable.

  6. An example of the use of the DELPHI method: future prospects of artificial heart techniques in France; Un exemple d'utilisation de la methode DELPHI: perspectives de developpement en France des techniques de coeur artificiel

    Energy Technology Data Exchange (ETDEWEB)

    Derian, Jean-Claude [Commissariat a l' energie atomique et aux energies alternatives - CEA, Centre d' Etudes Nucleaires de Fontenay-aux-Roses, Departement des Programmes, Section des Etudes Economiques Generales (France); Morize, Francoise [Commissariat a l' energie atomique et aux energies alternatives - CEA, Centre d' Etudes Nucleaires de Saclay, Institut National des Sciences et Techniques Nucleaires (France); Vernejoul, Pierre de [Faculte de Medecine Necker - Enfants Malades (France); Service Hospitalier Frederic Joliot (France); Vial, Renee [Direction de Protection et Surete Radiologiques (France)

    1971-07-01

    The artificial heart is still only a research project surrounded by numerous uncertainties which make it very difficult to estimate, at the moment, the possibilities for future development of this technique in France. A systematic analysis of the hazards which characterize this project has been undertaken in the following report: restricting these uncertainties has required a taking into account of opinions of specialists concerned with type of research or its upshot. We have achieved this by adapting an investigation technique which is still unusual in France, the DELPHI method. This adaptation has allowed the confrontation and statistical aggregation of the opinions given by a body of a hundred experts who were consulted through a program of sequential interrogations which studied in particular, the probable date of the research issue, the clinical cases which require the use of an artificial heart, as well as the probable future needs. After having taken into account the economic constraints, we can deduce from these results the probable amount of plutonium 238 needed in the hypothesis where isotopic generator would be retained for the energetics feeding of the artificial heart [French] Le coeur artificiel n'est encore actuellement qu'un projet de recherche auquel sont attachees de nombreuses incertitudes qui rendent difficile l'appreciation des possibilites de developpement futures de cette technique en France. Une analyse systematique des aleas qui caracterisent ce projet est entreprise dans l'etude ci-apres: circonscrire ces aleas necessite la prise en compte d'opinions emanant des specialistes concernes par cette recherche ou par son issue: c'est ce qui a ete realise en adaptant une methodologie non classique en France, la methode DELPHI. Cette adaptation a permis la confrontation et l'agregation statistique des opinions fournies par un college d'une centaine d'experts consultes par un programme d'interrogations sequentielles, envisageant en particulier les

  7. Developpement

    Directory of Open Access Journals (Sweden)

    Fok Michel

    2002-03-01

    Full Text Available Cette contribution souligne le fait que la plupart des innovations techniques ont bénéficié d’arrangements institutionnels adaptés qui ont favorisé l’adoption de pratiques techniques nouvelles. Elle met en exergue la nécessité de considérer conjointement les innovations techniques et institutionnelles pour aider à réaliser un gain de productivité qui permettrait de renforcer la place des pays cotonniers de l’Afrique de l’Ouest et du Centre dans le monde. Malgré leur intérêt, les nouvelles technologies ne constituent pas la réponse unique, comme ce serait le cas dans les pays économiquement développés, dans la conception de nouvelles techniques culturales pour ces pays africains. Ces techniques doivent d’abord être conformes aux contraintes des paysans, par exemple, en termes de limitation de main-d’œuvre ou de finance. Le comportement des petits paysans face à l’incertitude et la limitation de leurs moyens est brièvement étudié. Cette analyse permet de mettre en évidence les éléments de cahier des charges des nouvelles techniques destinées à soulager les contraintes des paysans. Des exemples de techniques possibles sont présentés. Des cas spécifiques d’interaction entre innovation technique et innovation institutionnelle sont examinés. La mise au point de techniques efficaces et adaptées exige un changement dans le financement et dans la réalisation de la recherche.

  8. Development and application of the discrete ordinate method in orthogonal curvilinear coordinates; Developpement et application de la methode des ordonnees discretes en coordonnees curvilignes orthogonales

    Energy Technology Data Exchange (ETDEWEB)

    Vaillon, R; Lallemand, M; Lemonnier, D [Ecole Nationale Superieure de Mecanique et d` Aerotechnique (ENSMA), 86 - Poitiers (France)

    1997-12-31

    The method of discrete ordinates, which is more and more widely used in radiant heat transfer studies, is mainly developed in Cartesian, (r,z) and (r,{Theta}) cylindrical, and spherical coordinates. In this study, the approach of this method is performed in orthogonal curvilinear coordinates: determination of the radiant heat transfer equation, treatment of the angular redistribution terms, numerical procedure. Some examples of application are described in 2-D geometry defined in curvilinear coordinates along a curve and at the thermal equilibrium. A comparison is made with the discrete ordinates method in association with the finite-volumes method in non structured mesh. (J.S.) 27 refs.

  9. Development and application of the discrete ordinate method in orthogonal curvilinear coordinates; Developpement et application de la methode des ordonnees discretes en coordonnees curvilignes orthogonales

    Energy Technology Data Exchange (ETDEWEB)

    Vaillon, R.; Lallemand, M.; Lemonnier, D. [Ecole Nationale Superieure de Mecanique et d`Aerotechnique (ENSMA), 86 - Poitiers (France)

    1996-12-31

    The method of discrete ordinates, which is more and more widely used in radiant heat transfer studies, is mainly developed in Cartesian, (r,z) and (r,{Theta}) cylindrical, and spherical coordinates. In this study, the approach of this method is performed in orthogonal curvilinear coordinates: determination of the radiant heat transfer equation, treatment of the angular redistribution terms, numerical procedure. Some examples of application are described in 2-D geometry defined in curvilinear coordinates along a curve and at the thermal equilibrium. A comparison is made with the discrete ordinates method in association with the finite-volumes method in non structured mesh. (J.S.) 27 refs.

  10. Development of characterization methods applied to radioactive wastes and waste packages; Le developpement des methodes de caracterisation appliquees aux dechets et colis de dechets radioactifs

    Energy Technology Data Exchange (ETDEWEB)

    Guy, C.; Bienvenu, Ph.; Comte, J.; Excoffier, E.; Dodi, A. [CEA Cadarache (DEN/CAD-DEC/SA3C/LARC), 13 - Saint Paul lez Durance (France); Gal, O.; Gmar, M.; Jeanneau, F.; Poumarede, B.; Tola, F. [CEA Saclay (DRT/SAC-DETECS/SSTM/L2MA), 91 - Gif sur Yvette (France); Moulin, V. [CEA Grenoble (DRT/GRE-LETI/DTBS/STD), 38 (France); Jallu, F.; Lyoussi, A.; Ma, J.L.; Oriol, L.; Passard, Ch.; Perot, B.; Pettier, J.L.; Raoux, A.C.; Thierry, R. [CEA Cadarache (DEN/CAD-DTN/SMTM/LMN), 13 - Saint Paul lez Durance (France)

    2004-07-01

    This document is a compilation of R and D studies carried out in the framework of the axis 3 of the December 1991 law about the conditioning and storage of high-level and long lived radioactive wastes and waste packages, and relative to the methods of characterization of these wastes. This R and D work has permitted to implement and qualify new methods (characterization of long-lived radioelements, high energy imaging..) and also to improve the existing methods by lowering detection limits and reducing uncertainties of measured data. This document is the result of the scientific production of several CEA laboratories that use complementary techniques: destructive methods and radiochemical analyses, photo-fission and active photonic interrogation, high energy imaging systems, neutron interrogation, gamma spectroscopy and active and passive imaging techniques. (J.S.)

  11. Developments based on stochastic and determinist methods for studying complex nuclear systems; Developpements utilisant des methodes stochastiques et deterministes pour l'analyse de systemes nucleaires complexes

    Energy Technology Data Exchange (ETDEWEB)

    Giffard, F.X

    2000-05-19

    In the field of reactor and fuel cycle physics, particle transport plays and important role. Neutronic design, operation and evaluation calculations of nuclear system make use of large and powerful computer codes. However, current limitations in terms of computer resources make it necessary to introduce simplifications and approximations in order to keep calculation time and cost within reasonable limits. Two different types of methods are available in these codes. The first one is the deterministic method, which is applicable in most practical cases but requires approximations. The other method is the Monte Carlo method, which does not make these approximations but which generally requires exceedingly long running times. The main motivation of this work is to investigate the possibility of a combined use of the two methods in such a way as to retain their advantages while avoiding their drawbacks. Our work has mainly focused on the speed-up of 3-D continuous energy Monte Carlo calculations (TRIPOLI-4 code) by means of an optimized biasing scheme derived from importance maps obtained from the deterministic code ERANOS. The application of this method to two different practical shielding-type problems has demonstrated its efficiency: speed-up factors of 100 have been reached. In addition, the method offers the advantage of being easily implemented as it is not very to the choice of the importance mesh grid. It has also been demonstrated that significant speed-ups can be achieved by this method in the case of coupled neutron-gamma transport problems, provided that the interdependence of the neutron and photon importance maps is taken into account. Complementary studies are necessary to tackle a problem brought out by this work, namely undesirable jumps in the Monte Carlo variance estimates. (author)

  12. Developments based on stochastic and determinist methods for studying complex nuclear systems; Developpements utilisant des methodes stochastiques et deterministes pour l'analyse de systemes nucleaires complexes

    Energy Technology Data Exchange (ETDEWEB)

    Giffard, F X

    2000-05-19

    In the field of reactor and fuel cycle physics, particle transport plays and important role. Neutronic design, operation and evaluation calculations of nuclear system make use of large and powerful computer codes. However, current limitations in terms of computer resources make it necessary to introduce simplifications and approximations in order to keep calculation time and cost within reasonable limits. Two different types of methods are available in these codes. The first one is the deterministic method, which is applicable in most practical cases but requires approximations. The other method is the Monte Carlo method, which does not make these approximations but which generally requires exceedingly long running times. The main motivation of this work is to investigate the possibility of a combined use of the two methods in such a way as to retain their advantages while avoiding their drawbacks. Our work has mainly focused on the speed-up of 3-D continuous energy Monte Carlo calculations (TRIPOLI-4 code) by means of an optimized biasing scheme derived from importance maps obtained from the deterministic code ERANOS. The application of this method to two different practical shielding-type problems has demonstrated its efficiency: speed-up factors of 100 have been reached. In addition, the method offers the advantage of being easily implemented as it is not very to the choice of the importance mesh grid. It has also been demonstrated that significant speed-ups can be achieved by this method in the case of coupled neutron-gamma transport problems, provided that the interdependence of the neutron and photon importance maps is taken into account. Complementary studies are necessary to tackle a problem brought out by this work, namely undesirable jumps in the Monte Carlo variance estimates. (author)

  13. Development of new non destructive methods for bituminized radioactive waste drums characterization; Developpement de nouvelles methodes de caracterisation non destructive pour des dechets radioactifs enrobes dans du bitume

    Energy Technology Data Exchange (ETDEWEB)

    Pin, P

    2004-10-15

    Radioactive waste constitute a major issue for the nuclear industry. One of the key points is their characterization to optimize their management: treatment and packaging, orientation towards the suited disposal. This thesis proposes an evaluation method of the low-energy photon attenuation, based on the gamma-ray spectra Compton continuum. Effectively, the {sup 241}Am measurement by gamma-ray spectrometry is difficult due to the low energy of its main gamma-ray (59.5 keV). The photon attenuation strongly depends on the bituminous mix composition, which includes very absorbing elements. As the Compton continuum also depends on this absorption, it is possible to link the 59.5 keV line attenuation to the Compton level. Another technique is proposed to characterize uranium thanks to its fluorescence X-rays induced by the gamma emitters already present in the waste. The uranium present in the drums disturbs the neutron measurements and its measurement by self-induced X-ray fluorescence allows to correct this interference. Due to various causes of error, the total uncertainty is around 50 % on the activity of the radioisotope {sup 241}Am, corrected by the peak to Compton technique. The same uncertainty is announced on the uranium mass measured by self induced X-ray fluorescence. As a consequence of these promising results, the two methods were included in the industrial project of the 'Marcoule Sorting Unit'. One major advantage is that they do not imply any additional material because they use information already present in the gamma-ray spectra. (author)

  14. Technical and Economic Problems Associated with the Development of Methods of Processing and Using Radioactive Waste; Problemes techniques et economiques lies au developpement des methodes de traitement et d'utilisation des dechets radioactifs

    Energy Technology Data Exchange (ETDEWEB)

    Thiriet, L; Sauteron, J; Oger, C [Commissariat a l' Energie Atomique, Fontenay-Aux-Roses (France). Centre d' Etudes Nucleaires

    1968-07-01

    The paper briefly reviews the various techniques used in processing the radioactive wastes which unavoidably result from the generation of electric power from nuclear sources. The paper goes on to define the relative importance, in nuclear fuel cycles, of the problem raised by these wastes. Emphasis is placed on the economic influence of management policies on the cost of power generation, and hence on the relative position of nuclear energy. A substantial percentage of these wastes can be economically utilized. Attention is drawn to the major technical and economic features of the industry which will come into being as a result of this utilization. The major uses anticipated are discussed: radiation sources, heat sources, auxiliary power generation. The paper concludes that satisfactory solutions have already been found to these problems, and describes possible improvements. (author) [French] La communication rappelle d'abord succinctement les differentes techniques de traitement des dechets radioactifs resultant necessairement de la production d'electricite d'origine nucleaire. On situe ensuite l'importance du probleme pose par ces residus dans le cycle du combustible nucleaire. On fait ressortir l'influence economique du choix des methodes de gestion sur le cout de production de l'energie, et par consequent sur la place devolue a l'energie nucleaire. Une part importante de ces dechets peut faire l'objet d'une utilisation rentable de l'industrie qui naitra de cette utilisation. Les principales applications envisagees sont evoquees: sources d'irradiation, sources chauffantes, generateurs auxiliaires d'energie. On conclut que d'ores et deja des solutions satisfaisantes ont ete apportees a ces problemes, et l'on decrit les perspectives d'amelioration concevables. (auteur)

  15. Analysis and development of spatial hp-refinement methods for solving the neutron transport equation; Analyse et developpement de methodes de raffinement hp en espace pour l'equation de transport des neutrons

    Energy Technology Data Exchange (ETDEWEB)

    Fournier, D.

    2011-10-10

    flux behaviour is very different depending on the energy, there is no reason to use the same spatial discretization. Such an approach implies to modify the initial estimators in order to take into account the coupling between groups. This study is done from a theoretical as well as from a numerical point of view. (author) [French] Pour la conception des coeurs de reacteurs de 4eme generation, une precision accrue est requise pour les calculs des differents parametres neutroniques. Les ressources memoire et le temps de calcul etant limites, une solution consiste a utiliser des methodes de raffinement de maillage afin de resoudre l'equation de transport des neutrons. Le flux neutronique, solution de cette equation, depend de l'energie, l'angle et l'espace. Les differentes variables sont discretisees de maniere successive. L'energie avec une approche multigroupe, considerant les differentes grandeurs constantes sur chaque groupe, l'angle par une methode de collocation, dite approximation SN. Apres discretisation energetique et angulaire, un systeme d'equations hyperboliques couplees ne dependant plus que de la variable d'espace doit etre resolu. Des elements finis discontinus sont alors utilises afin de permettre la mise en place de methodes de raffinement dite hp. La precision de la solution peut alors etre amelioree via un raffinement en espace (h-raffinement), consistant a subdiviser une cellule en sous-cellules, ou en ordre (p-raffinement) en augmentant l'ordre de la base de polynomes utilisee. Dans cette these, les proprietes de ces methodes sont analysees et montrent l'importance de la regularite de la solution dans le choix du type de raffinement. Ainsi deux estimateurs d'erreurs permettant de mener le raffinement ont ete utilises. Le premier, suppose des hypotheses de regularite tres fortes (solution analytique) alors que le second utilise seulement le fait que la solution est a variations bornees. La

  16. Awareness of households to the development of wind energy sites - Reporting on a survey; Receptivite des menages au developpement des sites eoliens. Rapport d'enquete

    Energy Technology Data Exchange (ETDEWEB)

    Voisard, M.

    2000-07-01

    This report for the Swiss Federal Office of Energy presents in tables and diagrams the results of a survey involving 421 households in Switzerland, about their awareness to energy issues and, in particular, to all what regards wind energy and wind power plants. Globally, 80% of the persons asked for their opinion believe that electric power demand will continue to increase. 66% of them are in favour of increased use of renewable energy sources and would consequently agree with a 10% more expensive end-user energy price. 89% of the persons taking part to the survey approve the installation of wind energy farms in Switzerland. Moreover, statistics indicates that the households living in regions already equipped with wind farms are significantly more favorable to the creation of new wind energy sites than those not living in these regions. By the end of the day, it turns out that the main reasons for accepting wind energy are environmental concerns as well as the fear of being obliged to use nuclear power. [French] Ce rapport presente par des graphiques et des tableaux le resultat d'un sondage d'opinion aupres de 421 menages en Suisse, sur la sensibilite du public aux problemes de l'energie et plus particulierement sur sa perception de tout ce qui concerne l'energie du vent et son exploitation par l'implantation d'eoliennes. Globalement, 80% des menages pensent que la demande d'energie electrique va poursuivre sa croissance. 66% d'entre eux sont favorables au developpement des energies renouvelables et prets a accepter en consequence une augmentation du prix de l'energie allant jusqu'a 10%. 89% des personnes interrogees sont favorables au developpement des eoliennes en Suisse. De plus, la statistique montre de maniere significative que les menages des regions dans lesquelles sont deja implantes des sites eoliens sont plus favorables au developpement des eoliennes que les autres. Finalement, le respect de l

  17. Awareness of households to the development of wind energy sites - Reporting on a survey; Receptivite des menages au developpement des sites eoliens. Rapport d'enquete

    Energy Technology Data Exchange (ETDEWEB)

    Voisard, M

    2000-07-01

    This report for the Swiss Federal Office of Energy presents in tables and diagrams the results of a survey involving 421 households in Switzerland, about their awareness to energy issues and, in particular, to all what regards wind energy and wind power plants. Globally, 80% of the persons asked for their opinion believe that electric power demand will continue to increase. 66% of them are in favour of increased use of renewable energy sources and would consequently agree with a 10% more expensive end-user energy price. 89% of the persons taking part to the survey approve the installation of wind energy farms in Switzerland. Moreover, statistics indicates that the households living in regions already equipped with wind farms are significantly more favorable to the creation of new wind energy sites than those not living in these regions. By the end of the day, it turns out that the main reasons for accepting wind energy are environmental concerns as well as the fear of being obliged to use nuclear power. [French] Ce rapport presente par des graphiques et des tableaux le resultat d'un sondage d'opinion aupres de 421 menages en Suisse, sur la sensibilite du public aux problemes de l'energie et plus particulierement sur sa perception de tout ce qui concerne l'energie du vent et son exploitation par l'implantation d'eoliennes. Globalement, 80% des menages pensent que la demande d'energie electrique va poursuivre sa croissance. 66% d'entre eux sont favorables au developpement des energies renouvelables et prets a accepter en consequence une augmentation du prix de l'energie allant jusqu'a 10%. 89% des personnes interrogees sont favorables au developpement des eoliennes en Suisse. De plus, la statistique montre de maniere significative que les menages des regions dans lesquelles sont deja implantes des sites eoliens sont plus favorables au developpement des eoliennes que les autres. Finalement, le respect de l'environnement et la crainte d'avoir a recourir a l

  18. Developpement des betons semi autoplacants a rheologie adaptee pour des infrastructures

    Science.gov (United States)

    Sotomayor Cruz, Cristian Daniel

    Au cours des dernières décennies, les infrastructures canadiennes et québécoises comportent plusieurs structures en béton armé présentant des problèmes de durabilité dus aux conditions climatiques sévères, à la mauvaise conception des structures, à la qualité des matériaux, aux types des bétons choisis, aux systèmes de construction ou à l'existence d'événements incontrôlables. En ce qui concerne le choix du béton pour la construction des infrastructures, une vaste gamme de béton divisée en deux principaux types peut être utilisée: le béton conventionnel vibré (BCV) et le béton autoplaçant (BAP). Dans le cas d'un BCV, la consolidation inadéquate par vibration a été un problème récurrent, occasionnant des dommages structuraux. Ceci a conduit à une réduction de la durabilité et à une augmentation du coût d'entretien et de réparation des infrastructures. Rien que l'utilisation d'un BAP a des avantages tels que l'élimination de la vibration, la réduction des coûts de main d'oeuvre et l'amélioration de la qualité des structures, néanmoins, le coût initial d'un BAP par rapport à un BCV ne permet pas encore de généraliser son utilisation dans l'industrie de la construction. Ce mémoire présente la conception d'une nouvelle gamme de béton semi-autoplaçant pour la construction des infrastructures (BSAP-I) exigeant une vibration minimale. Il s'agit de trouver un équilibre optimal entre la rhéologie et le coût initial du nouveau béton pour conférer une bonne performance structurale et économique aux structures. Le programme expérimental établi a premièrement permis d'évaluer la faisabilité d'utilisation des BSAP-I pour la mise en place des piliers d'une infrastructure de pont à Sherbrooke. En plus, l'utilisation d'un plan d'expériences a permis l'évaluation de trois paramètres de formulation sur les propriétés des mélanges de BSAP-I à l'état frais et durci. Finalement, l'évaluation de la performance des

  19. Developments in natural uranium - graphite reactors; Developpement des reacteurs a graphite et uranium naturel

    Energy Technology Data Exchange (ETDEWEB)

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

    1964-07-01

    in order to show the advantages resulting from such developments in gas-graphite natural metallic uranium reactor systems; these are: a doubling of the specific and volume powers, and a three-fold reduction in the number of channels. The research now under way will make it possible to calculate the reduction in capital costs which will result from these important technical advances. (authors) [French] Le programme francais de centrales a graphite et uranium naturel s'est developpe, d'EDF 1 a EDF 4 - dans la voie d'un accroissement de la puissance unitaire des installations, de la puissance specifique et de la puissance volumique, et d'une amelioration des conditions de securite de fonctionnement. La puissance elevee d'EDF 4 (500 MWe) et l'integration du circuit primaire dans le caisson, lui-meme en beton precontraint, permettent ainsi de tirer le meilleur parti des elements combustibles tubulaires utilises des EDF 1, et d'arriver ainsi a une solution tres satisfaisante. L'emploi d'un element combustible refroidi interieurement (element annulaire) permet de faire un nouveau pas en avant: il devient alors possible d'augmenter la pression du gaz de refroidissement sans craindre le fluage du tube d'uranium. L'emploi d'un caisson en beton precontraint permet une telle augmentation de pression, et l'integration du circuit primaire elimine les risques d'une depressurisation rapide qui aurait presente dans ce cas un risque majeur. On aborde dans ce rapport les principaux problemes poses par ce nouveau type de centrale et on indique les grandes lignes des recherches et etudes effectuees en France: - Les etudes de neutronique et thermique ont permis d'envisager l'emploi d'elements combustibles de grandes dimensions (diametre interne = 77 mm, diametre externe = 95 mm), tout en conservant l'uranium naturel. - Les problemes de fabrication de ces elements, et de leur comportement en pile, font l'objet d'un programme important, tant hors pile que dans les piles de puissance (EDF 2

  20. Developments in natural uranium - graphite reactors; Developpement des reacteurs a graphite et uranium naturel

    Energy Technology Data Exchange (ETDEWEB)

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

    1964-07-01

    in order to show the advantages resulting from such developments in gas-graphite natural metallic uranium reactor systems; these are: a doubling of the specific and volume powers, and a three-fold reduction in the number of channels. The research now under way will make it possible to calculate the reduction in capital costs which will result from these important technical advances. (authors) [French] Le programme francais de centrales a graphite et uranium naturel s'est developpe, d'EDF 1 a EDF 4 - dans la voie d'un accroissement de la puissance unitaire des installations, de la puissance specifique et de la puissance volumique, et d'une amelioration des conditions de securite de fonctionnement. La puissance elevee d'EDF 4 (500 MWe) et l'integration du circuit primaire dans le caisson, lui-meme en beton precontraint, permettent ainsi de tirer le meilleur parti des elements combustibles tubulaires utilises des EDF 1, et d'arriver ainsi a une solution tres satisfaisante. L'emploi d'un element combustible refroidi interieurement (element annulaire) permet de faire un nouveau pas en avant: il devient alors possible d'augmenter la pression du gaz de refroidissement sans craindre le fluage du tube d'uranium. L'emploi d'un caisson en beton precontraint permet une telle augmentation de pression, et l'integration du circuit primaire elimine les risques d'une depressurisation rapide qui aurait presente dans ce cas un risque majeur. On aborde dans ce rapport les principaux problemes poses par ce nouveau type de centrale et on indique les grandes lignes des recherches et etudes effectuees en France: - Les etudes de neutronique et thermique ont permis d'envisager l'emploi d'elements combustibles de grandes dimensions (diametre interne = 77 mm, diametre externe = 95 mm), tout en conservant l'uranium naturel. - Les problemes de fabrication de ces elements, et de leur comportement en pile

  1. Developpement d'une methode de Monte Carlo dependante du temps et application au reacteur de type CANDU-6

    Science.gov (United States)

    Mahjoub, Mehdi

    CANDU-6. Les sections efficaces dependantes du temps ont ete par la suite utilisees dans un calcul de diffusion espace-temps pour un reacteur CANDU-6 subissant un accident de type LOCA affectant la moitie du coeur afin d'observer son comportement durant toutes les phases de la perturbation. Dans la phase de developpement, nous avons choisi de demarrer avec le code OpenMC, developpe au MIT,comme plateforme initiale de developpement. L'introduction et le traitement des neutrons retardes durant la simulation ont presente un grand defi a surmonter. Il est important de noter que le code developpe utilisant la methode Monte Carlo peut etre utilise a grande echelle pour la simulation de tous les types des reacteurs nucleaires si les supports informatiques sont disponibles.

  2. Study of the asymptotic expansion of multiple integrals in mathematical physics; Etudes sur les developpements asymptotiques des integrales multiples de la physique mathematique

    Energy Technology Data Exchange (ETDEWEB)

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

    1968-07-01

    , provided one interprets in a proper manner the results derived from the two methods, especially the expression of the geometrical wave. (author) [French] Nous avons applique la methode de la phase stationnaire pour evaluer les integrales doubles et multiples du type: (A) U(k) = g(x)e{sup ik{phi}}{sup (x)} d(x), (x)=(x{sub 1},..., x{sub n}) pour les grandes valeurs du parametre k. Dans la premiere partie nous avons etendu d'une maniere rigoureuse la methode de la phase stationnaire aux integrales doubles et multiples de type (A). De plus, nous avons obtenu un developpement asymptotique de (A), lorsque l'amplitude et la phase peuvent se developper sous forme canonique au voisinage de points critiques ou stationnaires de l'integrale (A). Ce developpement contient comme cas particuliers tous les cas importants dans les applications physiques et particulierement en diffraction et diffusion d'ondes electromagnetiques et corpusculaires par des systemes optiques, corps diffractants et potentiels de diffusions. Dans la seconde partie nous avons considere le probleme de la convergence du developpement de la contribution principale a l'integrale, au sens asymptotique de Poincare. La preuve est basee sur la methode des majorantes, utilisee en analyse mathematique. La troisieme partie contient la derivation des series asymptotiques diverses, due aux types varies de points critiques ou stationnaires lies aux fonctions d'amplitude et de phase. Dans la quatrieme partie nous avons generalise la methode aux integrales multiples et au cas ou le parametre k entre implicitement dans la fonction de phase. Ce dernier type d'integrales permet l'extension du premier type a de nombreux problemes physiques, par exemple a la propagation d'ondes en milieux dispersifs et absorbants. Au dernier chapitre, nous faisons l'etude des integrales doubles de diffractions (theorie de Kirchhoff) et nous comparons les resultats par l'application de la methode de la phase stationnaire et de la methode Young

  3. Recent developments in the field of refractory fuels; Developpements recents dans le domaine des combustibles refractaires

    Energy Technology Data Exchange (ETDEWEB)

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

    1964-07-01

    or arc fusion). This latter method is based on fusion by electronic bombardment associated with the continuous casting. (authors) [French] L'effort des recentes annees au Commissariat a l'Energie Atomique dans le domaine des combustibles ceramiques a surtout porte sur le bi-oxyde d'uranium et les alliages uranium-carbone. Le bi-oxyde d'uranium est etudie dans l'optique de son utilisation comme combustible de la premiere charge d'EL 4, dans laquelle on impose au point le plus charge une conductibilite thermique integree de 29 W/cm pour une temperature de surface de 750 C environ. On s'est specialement preoccupe de mettre en place un procede de preparation d'une poudre de bi-oxyde de bonnes caracteristiques et le frittage industriel de cette poudre, et d'evaluer les principales proprietes des corps obtenus en relation avec les conditions des corps obtenus en relation avec les conditions prevues de leur utilisation: - aspect de micro-structure et distribution des pores, - comportement mecanique et thermique en geometrie cylindrique, - controle de l'oxygene excedentaire dans les produits industriels, - compatibilite aux hautes temperatures avec les oxydes utilisables comme isolants thermiques, - comportement des produits de fission gazeux a haute temperature apres irradiation ou au cours de l'irradiation. Dans le cas des carbures d'uranium, notre but a ete de determiner les conditions de fabrication industrielle d'un combustible satisfaisant de composition voisine de UC. Ceci nous a conduits a entreprendre un certain nombre d'etudes fondamentales Sur le domaine d'existence de UC non stoechiometrique, - l'influence, sur les proprietes de UC, des elements O et N dissous dans ce materiau, - la compatibilite des alliages uranium-carbone avec differents materiaux de gaine metalliques ou ceramiques, - la corrosion des alliages uranium-carbone par H{sub 2}O et CO{sub 2}, - les methodes de preparation d'echantillons de haute purete, - les dispositifs d'irradiation en pile

  4. Development of numerical methods to calculate the propagation and the absorption of the hybrid wave in tokamaks; Developpement des methodes numeriques pour la resolution de la propagation et de l`absorption de l`onde hybride dans les tokamaks

    Energy Technology Data Exchange (ETDEWEB)

    Sebelin, E

    1997-12-15

    Full-wave calculations based on trial functions are carried out for solving the lower hybrid current drive problem in tokamaks. A variational method is developed and provides an efficient system to describe in a global manner both the propagation and the absorption of the electromagnetic waves in plasmas. The calculation is fully carried out in the case of circular and concentric flux surfaces. The existence and uniqueness of the solution of the wave propagation equation is mathematically proved. The first realistic simulations are performed for the high aspect ratio tokamak TRIAM-1M. It is checked that the main features of the lower-hybrid wave dynamics are well described numerically. (A.C.) 81 refs.

  5. Developpement D'un Modele Climatique Regional: Fizr Simulation des Conditions de Janvier de la Cote Ouest Nord Americaine

    Science.gov (United States)

    Goyette, Stephane

    1995-11-01

    Le sujet de cette these concerne la modelisation numerique du climat regional. L'objectif principal de l'exercice est de developper un modele climatique regional ayant les capacites de simuler des phenomenes de meso-echelle spatiale. Notre domaine d'etude se situe sur la Cote Ouest nord americaine. Ce dernier a retenu notre attention a cause de la complexite du relief et de son controle sur le climat. Les raisons qui motivent cette etude sont multiples: d'une part, nous ne pouvons pas augmenter, en pratique, la faible resolution spatiale des modeles de la circulation generale de l'atmosphere (MCG) sans augmenter a outrance les couts d'integration et, d'autre part, la gestion de l'environnement exige de plus en plus de donnees climatiques regionales determinees avec une meilleure resolution spatiale. Jusqu'alors, les MCG constituaient les modeles les plus estimes pour leurs aptitudes a simuler le climat ainsi que les changements climatiques mondiaux. Toutefois, les phenomenes climatiques de fine echelle echappent encore aux MCG a cause de leur faible resolution spatiale. De plus, les repercussions socio-economiques des modifications possibles des climats sont etroitement liees a des phenomenes imperceptibles par les MCG actuels. Afin de circonvenir certains problemes inherents a la resolution, une approche pratique vise a prendre un domaine spatial limite d'un MCG et a y imbriquer un autre modele numerique possedant, lui, un maillage de haute resolution spatiale. Ce processus d'imbrication implique alors une nouvelle simulation numerique. Cette "retro-simulation" est guidee dans le domaine restreint a partir de pieces d'informations fournies par le MCG et forcee par des mecanismes pris en charge uniquement par le modele imbrique. Ainsi, afin de raffiner la precision spatiale des previsions climatiques de grande echelle, nous developpons ici un modele numerique appele FIZR, permettant d'obtenir de l'information climatique regionale valide a la fine echelle spatiale

  6. Contributions to the Monte-Carlo methods development for the criticality studies: the anisotropy diffusion representation, the perturbations study; Contributions au developpement des methodes de Monte-Carlo pour les etudes de criticite: representation de l'anisotropie de la diffusion, etude des perturbations

    Energy Technology Data Exchange (ETDEWEB)

    Le Cocq, A

    1998-11-23

    The aim of this work is the performances improvement of the Monte-Carlo codes for the criticality studies. MORET IV is especially concerned. With multigroup approximations, the anisotropy equations are very irregular and show quick variations. In a Monte-Carlo codes, they are estimated only by the first coefficients of Legendre polynomials development. Many methods have been characterised using variable number of these coefficients, allowing their reconstruction. So reference representations were defined. Thus they showed that the approximation by only one Dirac could lead to a reactivity under-evaluations. Referring to these representations, new methods have been introduced in MORET IV and instructions have been proposed. Two methods (the correlated samples method and the derivatives sampling method) have been studied to define the divergence between two closely configurations result. A few variance formula of the collision density variation for an infinite medium to an energy group, have been established. These formula have been perfected by simulation for a finite medium. (A.L.B.)

  7. Contributions to the Monte-Carlo methods development for the criticality studies: the anisotropy diffusion representation, the perturbations study; Contributions au developpement des methodes de Monte-Carlo pour les etudes de criticite: representation de l'anisotropie de la diffusion, etude des perturbations

    Energy Technology Data Exchange (ETDEWEB)

    Le Cocq, A

    1998-11-23

    The aim of this work is the performances improvement of the Monte-Carlo codes for the criticality studies. MORET IV is especially concerned. With multigroup approximations, the anisotropy equations are very irregular and show quick variations. In a Monte-Carlo codes, they are estimated only by the first coefficients of Legendre polynomials development. Many methods have been characterised using variable number of these coefficients, allowing their reconstruction. So reference representations were defined. Thus they showed that the approximation by only one Dirac could lead to a reactivity under-evaluations. Referring to these representations, new methods have been introduced in MORET IV and instructions have been proposed. Two methods (the correlated samples method and the derivatives sampling method) have been studied to define the divergence between two closely configurations result. A few variance formula of the collision density variation for an infinite medium to an energy group, have been established. These formula have been perfected by simulation for a finite medium. (A.L.B.)

  8. 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.)

  9. New modelling method for fast reactor neutronic behaviours analysis; Nouvelles methodes de modelisation neutronique des reacteurs rapides de quatrieme Generation

    Energy Technology Data Exchange (ETDEWEB)

    Jacquet, P.

    2011-05-23

    Due to safety rules running on fourth generation reactors' core development, neutronics simulation tools have to be as accurate as never before. First part of this report enumerates every step of fast reactor's neutronics simulation implemented in current reference code: ECCO. Considering the field of fast reactors that meet criteria of fourth generation, ability of models to describe self-shielding phenomenon, to simulate neutrons leakage in a lattice of fuel assemblies and to produce representative macroscopic sections is evaluated. The second part of this thesis is dedicated to the simulation of fast reactors' core with steel reflector. These require the development of advanced methods of condensation and homogenization. Several methods are proposed and compared on a typical case: the ZONA2B core of MASURCA reactor. (author) [French] Les criteres de surete qui regissent le developpement de coeurs de reacteurs de quatrieme generation implique l'usage d'outils de calcul neutronique performants. Une premiere partie de la these reprend toutes les etapes de modelisation neutronique des reacteurs rapides actuellement d'usage dans le code de reference ECCO. La capacite des modeles a decrire le phenomene d'autoprotection, a representer les fuites neutroniques au niveau d'un reseau d'assemblages combustibles et a generer des sections macroscopiques representatives est appreciee sur le domaine des reacteurs rapides innovants respectant les criteres de quatrieme generation. La deuxieme partie de ce memoire se consacre a la modelisation des coeurs rapides avec reflecteur acier. Ces derniers necessitent le developpement de methodes avancees de condensation et d'homogenisation. Plusieurs methodes sont proposees et confrontees sur un probleme de modelisation typique: le coeur ZONA2B du reacteur maquette MASURCA

  10. Developpements numeriques recents realises en aeroelasticite chez Dassault Aviation pour la conception des avions de combat modernes et des avions d’affaires

    Science.gov (United States)

    2003-03-01

    Cost through Advanced Modelling and Virtual Simulation [La reduction des couts et des delais d’acquisition des vehicules militaires par la modelisation...sont les 6quations de restitution, par le mod~e, des frdquences et des amortissements des modes adrodlastiques mesurds h une prdcision F- donnde. Afin... amortissements mesurds h 37800 Pa et 60000 Pa (points nettemnent inferieurs A la vitesse critique). Comme le montre ce diagramme, le calcul, recal6 h

  11. Study and development of a method allowing the identification of actinides inside nuclear waste packages, by active neutron or photon interrogation and delayed gamma-ray spectrometry; Etude et developpement d'une technique de dosage des actinides dans les colis de dechets radioactifs par interrogation photonique ou neutronique active et spectrometrie des gamma retardes

    Energy Technology Data Exchange (ETDEWEB)

    Carrel, F

    2007-10-15

    An accurate estimation of the alpha-activity of a nuclear waste package is necessary to select the best mode of storage. The main purpose of this work is to develop a non-destructive active method, based on the fission process and allowing the identification of actinides ({sup 235}U, {sup 238}U, {sup 239}Pu). These three elements are the main alpha emitters contained inside a package. Our technique is based on the detection of delayed gammas emitted by fission products. These latter are created by irradiation with the help of a neutron or photon beam. Performances of this method have been investigated after an Active Photon or Neutron Interrogation (INA or IPA). Three main objectives were fixed in the framework of this thesis. First, we measured many yields of photofission products to compensate the lack of data in the literature. Then, we studied experimental performances of this method to identify a given actinide ({sup 239}Pu in fission, {sup 235}U in photofission) present in an irradiated mixture. Finally, we assessed the application of this technique on different mock-up packages for both types of interrogation (118 l mock-up package containing EVA in fission, 220 l mock-up package with a wall of concrete in photofission). (author)

  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

  13. Developpement energetique par modelisation et intelligence territoriale: Un outil de prise de decision participative pour le developpement durable des projets eoliens

    Science.gov (United States)

    Vazquez Rascon, Maria de Lourdes

    This thesis focuses on the implementation of a participatory and transparent decision making tool about the wind farm projects. This tool is based on an (argumentative) framework that reflects the stakeholder's values systems involved in these projects and it employs two multicriteria methods: the multicriteria decision aide and the participatory geographical information systems, making it possible to represent this value systems by criteria and indicators to be evaluated. The stakeholder's values systems will allow the inclusion of environmental, economic and social-cultural aspects of wind energy projects and, thus, a sustainable development wind projects vision. This vision will be analyzed using the 16 sustainable principles included in the Quebec's Sustainable Development Act. Four specific objectives have been instrumented to favor a logical completion work, and to ensure the development of a successfultool : designing a methodology to couple the MCDA and participatory GIS, testing the developed methodology by a case study, making a robustness analysis to address strategic issues and analyzing the strengths, weaknesses, opportunities and threads of the developed methodology. Achieving the first goal allowed us to obtain a decision-making tool called Territorial Intelligence Modeling for Energy Development (TIMED approach). The TIMED approach is visually represented by a figure expressing the idea of a co-construction decision and where ail stakeholders are the focus of this methodology. TIMED is composed of four modules: Multi-Criteria decision analysis, participatory geographic Information systems, active involvement of the stakeholders and scientific knowledge/local knowledge. The integration of these four modules allows for the analysis of different implementation scenarios of wind turbines in order to choose the best one based on a participatory and transparent decision-making process that takes into account stakeholders' concerns. The second objective

  14. Present development of scintillator counters in France; Etat actuel du developpement des compteurs a scintillation en France

    Energy Technology Data Exchange (ETDEWEB)

    Koechlin, Y; Koch, L; Lansiart, A [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires; Pietri, G [Laboratoire d' Electronique et de Physique Appliquee (France)

    1958-07-01

    For a number of years photomultipliers and scintillators have been produced on an industrial scale in France. The AEC has accepted the task of testing their performance, and advising the industry in consequence. This combined effort has resulted in the wide range of photomultipliers and scintillators summarised in the following paper. (author)Fren. [French] La france fabrique industriellement depuis quelques annees des photomultiplicateurs et des scintillateurs. Le Commissariat a l'Energie atomique s'est charge de mesurer leurs performances et de conseiller l'industrie fran ise a ce sujet. C'est ainsi que nous disposons actuellement de toute une gamme de photomultiplicateurs et de scintillateurs fran is dont nous donnons ci-dessous un apercu. (auteur)

  15. Contribution des radios communautaires a l'education des ...

    African Journals Online (AJOL)

    Contribution des radios communautaires a l'education des populations rurales pour un developpement durable au Benin: etude de cas. ... Journal de la Recherche Scientifique de l'Université de Lomé. Journal Home · ABOUT THIS JOURNAL ...

  16. Development of asymptotic methods for the study of interactions between cold atoms: determination of scattering lengths of sodium and cesium; Developpement de methodes asymptotiques pour l'etude des interactions entre atomes froids: determination de longueurs de diffusion du sodium et du cesium

    Energy Technology Data Exchange (ETDEWEB)

    T' Jampens, B

    2002-12-15

    Precise knowledge of cold-atom collision properties is essential for the studies of Bose-Einstein condensation or cold molecule formation. In such experiments, the interaction mainly occurs at rather large interatomic distance, in the so-called asymptotic region. We have developed a purely asymptotic method which allows us to fully describe the collision properties of cold alkali atoms without using the inner part of the molecular potentials, which is often known with a poor precision. The key point of the method is the setting of nodal lines, which are the lines connecting the nodes of successive radial wavefunctions near the ground state threshold. Within the framework of Born-Oppenheimer approximation, computing such nodal lines, by numerical integration of the radial Schroedinger equation in the asymptotic region only, provides a very simple way to derive scattering lengths from observed bound level positions. The method has been extended to the multichannel case and appears now as a genuine parametric method, in which a few parameters (some chosen nodal lines) replace the inner part of the potentials. These nodal lines are used as fitting parameters, which are adjusted on experimental results. Once these parameters have been determined, any collision property such as scattering lengths, clock shifts or magnetic field induced Feshbach resonances can be deduced in principle. This method has been applied to obtain the collision properties of ultracold sodium and cesium atoms. (author)

  17. 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)

  18. Development of numerical methods for reactive transport; Developpement de methodes numeriques pour le transport reactif

    Energy Technology Data Exchange (ETDEWEB)

    Bouillard, N

    2006-12-15

    When a radioactive waste is stored in deep geological disposals, it is expected that the waste package will be damaged under water action (concrete leaching, iron corrosion). Then, to understand these damaging processes, chemical reactions and solutes transport are modelled. Numerical simulations of reactive transport can be done sequentially by the coupling of several codes. This is the case of the software platform ALLIANCES which is developed jointly with CEA, ANDRA and EDF. Stiff reactions like precipitation-dissolution are crucial for the radioactive waste storage applications, but standard sequential iterative approaches like Picard's fail in solving rapidly reactive transport simulations with such stiff reactions. In the first part of this work, we focus on a simplified precipitation and dissolution process: a system made up with one solid species and two aqueous species moving by diffusion is studied mathematically. It is assumed that a precipitation dissolution reaction occurs in between them, and it is modelled by a discontinuous kinetics law of unknown sign. By using monotonicity properties, the convergence of a finite volume scheme on admissible mesh is proved. Existence of a weak solution is obtained as a by-product of the convergence of the scheme. The second part is dedicated to coupling algorithms which improve Picard's method and can be easily used in an existing coupling code. By extending previous works, we propose a general and adaptable framework to solve nonlinear systems. Indeed by selecting special options, we can either recover well known methods, like nonlinear conjugate gradient methods, or design specific method. This algorithm has two main steps, a preconditioning one and an acceleration one. This algorithm is tested on several examples, some of them being rather academical and others being more realistic. We test it on the 'three species model'' example. Other reactive transport simulations use an external chemical code CHESS. For a

  19. Development of numerical methods for reactive transport; Developpement de methodes numeriques pour le transport reactif

    Energy Technology Data Exchange (ETDEWEB)

    Bouillard, N

    2006-12-15

    When a radioactive waste is stored in deep geological disposals, it is expected that the waste package will be damaged under water action (concrete leaching, iron corrosion). Then, to understand these damaging processes, chemical reactions and solutes transport are modelled. Numerical simulations of reactive transport can be done sequentially by the coupling of several codes. This is the case of the software platform ALLIANCES which is developed jointly with CEA, ANDRA and EDF. Stiff reactions like precipitation-dissolution are crucial for the radioactive waste storage applications, but standard sequential iterative approaches like Picard's fail in solving rapidly reactive transport simulations with such stiff reactions. In the first part of this work, we focus on a simplified precipitation and dissolution process: a system made up with one solid species and two aqueous species moving by diffusion is studied mathematically. It is assumed that a precipitation dissolution reaction occurs in between them, and it is modelled by a discontinuous kinetics law of unknown sign. By using monotonicity properties, the convergence of a finite volume scheme on admissible mesh is proved. Existence of a weak solution is obtained as a by-product of the convergence of the scheme. The second part is dedicated to coupling algorithms which improve Picard's method and can be easily used in an existing coupling code. By extending previous works, we propose a general and adaptable framework to solve nonlinear systems. Indeed by selecting special options, we can either recover well known methods, like nonlinear conjugate gradient methods, or design specific method. This algorithm has two main steps, a preconditioning one and an acceleration one. This algorithm is tested on several examples, some of them being rather academical and others being more realistic. We test it on the 'three species model'' example. Other reactive transport simulations use an external

  20. La croissance demographique et son impact sur le developpement ...

    African Journals Online (AJOL)

    La croissance demographique et son impact sur le developpement des grandes villes au ... La ville de Porto-Novo au Bénin n'est pas en marge de cette réalité que ... and the need for improving its framework of life through its development.

  1. Study of the interaction operator between two groups of particles in a completely ionised plasma. Development of the distribution functions in a series of orthogonal polynomials (1963); Etude de l'operateur d'interaction entre deux groupes de particules dans un plasma completement ionise. Developpement des fonctions de distribution en series de polynomes orthogonaux (1963)

    Energy Technology Data Exchange (ETDEWEB)

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

    1963-05-15

    indiquee par ROSENBLUTH - MAC DONALD - JUDD. On developpe les fonctions de distribution en series de polynomes orthogonaux dans l'espace des vitesses. Dans un premier stade ces fonctions sont d'abord decomposees en series d'harmoniques spheriques (ou, sous une forme equivalente, en series de produits scalaires de tenseurs cartesiens irreductibles), avec des coefficients qui sont fonction du module de la vitesse ainsi que des coordonnees d'espace et de temps. Dans le second stade ces coefficients sont developpes en series de fonctions orthogonales du module de la vitesse; on represente l'harmonique d'ordre 1 par le produit d'une distribution de MAXWELL et d'une serie de polynomes de SONINE, d'indice 1 + 1/2, qui ont pour variable l'energie reduite des particules (rapportee a une temperature de base), avec des coefficients qui ne dependent plus que des coordonnees d'espace et de temps. Dans la premiere partie on etablit des relations entre les coefficients du developpement et les moments de la fonction de distribution ainsi que les grandeurs hydrodynamiques. Dans la deuxieme partie on reporte dans l'equation de FOKKER-PLANCK le developpement en serie d'harmoniques spheriques. On donne l'expression generale du second membre et les expressions particulieres correspondant aux cas ou l'operateur est linearise. Dans la troisieme partie on reporte dans l'equation de FOKKER-PLANCK le developpement complet en serie de polynomes orthogonaux. Les coefficients numeriques des termes d'interaction s'obtiennent par le developpement en serie de fonctions generatrices. On donne l'expression des fonctions generatrices pour tous les harmoniques dans le cas de l'operateur linearise, ainsi que les equations de transport pour les quatre premiers harmoniques. (auteur)

  2. Methods for determining thermal stresses values. Some examples relating to nuclear reactors; Methodes de determination des contraintes thermiques. Quelques exemples d'application aux reacteurs

    Energy Technology Data Exchange (ETDEWEB)

    Bernard, J; Gautier, A [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires; Peres, A [Israel Institute of Technology, Dept. of Nuclear Science Technion (Israel)

    1958-07-01

    As modern techniques develop more elaborate machines, and make their way towards higher and higher temperatures and pressures, the thermal stresses become a matter of major importance in the design of mechanical structures. In the first part of this paper, the authors examine the problem from a theoretical standpoint, and try to evaluate the aptitude and limitation of mathematical techniques to attain the quantitative values of thermal stresses. This paper deals mainly with the experimental methods to measure thermal stresses. The authors show some examples relating to nuclear reactors. (author)Fren. [French] Au fur et a mesure que la technique moderne developpe des machines plus poussees et s'oriente vers des temperatures et des pressions toujours plus elevees, les contraintes thermiques deviennent un facteur d'importance capitale dans le calcul des structures mecaniques. Les auteurs examinent d'abord l'aspect theorique du probleme, ainsi que l'aptitude et les limites du calcul pour exprimer quantitativement la valeur des contraintes thermiques. Les auteurs exposent principalement, ensuite, les methodes experimentales qui permettent de mesurer ces contraintes, et illustrent cet expose de quelques exemples relatifs aux installations nucleaires. (auteur)

  3. Recent developments concerning French fuel elements used in natural uranium - graphite - CO{sub 2} reactor systems; Developpements recents des elements combustibles francais de la filiere uranium naturel - graphite - CO{sub 2}

    Energy Technology Data Exchange (ETDEWEB)

    Salesse, M; Stohr, J A; Jeanpierre, G [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1964-07-01

    internal can of the annular element, has necessitated very much research work. - the exact temperature drop at the contact between the uranium and the can, and the strength of the lower end of the cartridge are points which are increasingly crucial in the case of the annular element. All in all the annular element thus calls for a great research effort. This effort is justified by the big step forwards in which it will result in the case of the EDF reactors thanks to its high specific power and to the high weight of uranium in each cartridge. (authors) [French] La politique choisie en France pour le developpement des elements combustibles destines aux reacteurs de l'Electricite de France, consiste a chercher, pour chaque pile nouvelle, a beneficier au maximum des progres techniques les plus recents en etudiant chaque fois un nouvel element combustible permettant une puissance par canal aussi elevee que possible. Les derniers elements combustibles ainsi etudies par le Commissariat a l'Energie Atomique sont de deux types differents: un element a tube d'uranium ferme aux deux extremites et refroidi exterieurement (ce type d'element, retenu pour les reacteurs EDF 2, EDF 3 et EDF 4 permet des puissances specifiques maximum de l'ordre de 6 MW/t). Un element a tube d'uranium ouvert, refroidi interieurement et exterieurement, appele clemont annulaire et dont on etudie la possibilite pour EDF5. Un tel element peut permettre des puissances specifiques superieures a 12 MW/t. Ces deux types d'elements possedent des caracteristiques communes: la gaine, pour le refroidissement externe, comporte des ailettes en chevron. Ce type de profil, qui a recu recemment des ameliorations notables augmentant son efficacite thermique, a l'avantage important d'eviter les vibrations de cartouche mais a pose des problemes technologiques de tenue au cyclage thermique qui ont necessite une etude approfondie. les cartouches sont placees a l'interieur de chemise en graphite, ce qui limite les efforts

  4. Beach sediments drift study by means of radioactive tracers; L'etude du transport littoral par la methode des traceurs radioactifs

    Energy Technology Data Exchange (ETDEWEB)

    Hours, R [Commissariat a l' Energie Atomique, Saclay (France).Centre d' Etudes Nucleaires; Jaffry, P [Electricite de France (EDF), 78 - Chatou (France). Lab. National d' Hydraulique

    1959-07-01

    The present state of the sediments drift studies by means of radioactive tracers is exposed. Various processes of labelling, immersion and detection, used in France and other countries, are reviewed. A more extended analysis of some aspects of the problem by the same authors can be found in 'La Houille Blanche', number 3, may-june 1959 (Rapport C.E.A. number 1269). (author) [French] L'etude du transport littoral des sediments et galets par la methode des traceurs radioactifs est en plein developpement. Le present rapport precise l'etat actuel de la question. Les techniques de marquage, d'immersion et de detection utilisees en France et a l'etranger sont decrites; une analyse plus detaillee de certains aspects de la question est presentee par les memes auteurs dans 'La Houille Blanche', numero 3, mai-juin 1959 (Rapport C.E.A. numero 1269). (auteur)

  5. Participation en projets et dissonance cognitive des beneficiaires en ...

    African Journals Online (AJOL)

    Participation en projets et dissonance cognitive des beneficiaires en Afrique : la symbolique des paradoxes de la double contrainte institutionnelle dans la mise en oeuvre d'un projet de developpement au Benin.

  6. Developpement dune methode de simulation de pompage au sein d'un compresseur multi-etage

    Science.gov (United States)

    Dumas, Martial

    Surge is an unsteady phenomenon which appears when a compressor operates at a mass flow that is too low relative to its design point. This aerodynamic instability is characterized by large oscillations in pressure and mass flow, resulting in a sudden drop in power delivered by a gas turbine engine and possibly important damage to engine components. The methodology developed in this thesis allows for the simulations of the flow behavior inside a multi-stage compressor during surge and, by extension, predict at the design phase the time variation of aerodynamic forces on the blades and of the pressure and temperature at bleed locations inside the compressors for turbine cooling. While the compressor is the component of interest and the trigger for surge, the flow behavior during this event is also dependent on other engine components (combustion chamber, turbine, ducts). However, the simulation of the entire gas turbine engine cannot be carried out in a practical manner with existing computational technologies. The approach taken consists of coupling 3-D RANS CFD simulations of the compressor with 1-D equations modeling the behavior of the other components applied as dynamic boundary conditions. The method was put into practice in a commercial RANS CFD code (ANSYS CFX) whose integrated options facilitated the implementation of the 1-D equations into the dynamic boundary conditions of the computational domain. In addition, in order to limit computational time, only one blade passage was simulated per blade row to capture surge which is essentially a one-dimensional phenomenon. This methodology was applied to several compressor geometries with distinct features. Simulations on a low-speed (incompressible) three-stage axial compressor allowed for a validation with experimental data, which showed that the pressure and mass flow oscillations are captured well. This comparison also highlighted the strong dependence of the oscillation frequency on the volume of the

  7. L’évaluation des dimensions territoriale et institutionnelle du developpement durable : le cas des politiques de Gestion Intégrée des Zones Côtières

    Directory of Open Access Journals (Sweden)

    Hélène Rey-Valette

    2006-12-01

    Full Text Available Cet article se propose d’étudier dans quelle mesure la prise en compte du développement durable au sens d’un nouveau référentiel prônant des logiques de transversalité, de long terme et de participation pour les politiques publiques oblige à revoir les méthodes d’évaluation de ces politiques. Le champ d’étude porte sur la Gestion Intégrée des Zones Côtières (GIZC qui est un cas exemplaire de la prise en compte du développement durable à l’échelle d’un espace spécifique, le littoral, par ailleurs porteur d’enjeux importants. L’analyse est centrée sur la dimension institutionnelle du développement durable ainsi que sur l’évaluation de la gouvernance au sein des dispositifs de GIZC, et plus généralement sur l’évaluation des politiques d’aménagement des territoires.This paper studies to what extent public policy evaluation practices need to be revised whilst considering sustainable development as a system of references regarding transversality, the long-run as well as public participation. We focus on Integrated Coastal Zone Management (ICZM that takes into account sustainable development in costal management. We analyze the institutional part of sustainable development and governance processes in ICZM implementation schemes, and we show new insights in planning policy evaluation.

  8. Neutron thermalization in absorbing infinite homogeneous media: theoretical methods; Methodes theoriques pour l'etude de la thermalisation des neutrons dans les milieux absorbants infinis et homogenes

    Energy Technology Data Exchange (ETDEWEB)

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

    1963-11-15

    After a general survey of the theory of neutron thermalization in homogeneous media, one introduces, through a proper formulation, a simplified model generalizing both the Horowitz model (generalized heavy free gas approximation) and the proton gas model. When this model is used, the calculation of spectra is reduced to the solution of linear second order differential equations. Since it depends on two arbitrary functions, the model gives a good approximation of any usual moderator for reactor physics purposes. The choice of these functions is discussed from a theoretical point of view; a method based on the consideration of the first two moments of the scattering law is investigated. Finally, the possibility of discriminating models by using experimental informations is considered. (author) [French] Apres un passage en revue de generalites sur la thermalisation des neutrons dans les milieux homogenes, on developpe un formalisme permettant de definir et d'etudier un modele simplifie de thermaliseur. Ce modele generalise l'approximation proposee par J. HOROWITZ (''gaz lourd generalise'') et comporte comme cas particulier le modele ''hydrogene gazeux monoatomique''. Il ramene le calcul des spectres a la resolution d'equations differentielles lineaires du second ordre. Il fait intervenir deux fonctions arbitraires, ce qui lui permet de representer les thermaliseurs usuels de facon satisfaisante pour les besoins de la physique des reacteurs. L'ajustement theorique de ces fonctions est discute; on etudie une methode basee sur la consideration des deux premiers moments de la loi de diffusion. On envisage enfin la possibilite de discriminer les modeles d'apres des renseignements d'origine experimentale. (auteur)

  9. Notes on the development of the gibbs potential; Sur le developpement du potentiel de gibbs

    Energy Technology Data Exchange (ETDEWEB)

    Bloch, C; Dominicis, C de [Commissariat a l' Energie Atomique, Saclay (France).Centre d' Etudes Nucleaires

    1959-07-01

    A short account is given of some recent work on the perturbation expansion of the Gibbs potential of quantum statistical mechanics. (author) [French] Expose en resume de quelques travaux sur le developpement dans la theorie des perturbations du potentiel de Gibbs de la Mecanique Statistique. (auteur)

  10. Ex-post evaluation of local energy efficiency and demand-side management operations - State of the art, bottom-up methods, applied examples and approach for the development of an evaluation practical culture; L'evaluation ex-post des operations locales de maitrise de la demande en energie - Etat de l'art, methodes bottom-up, exemples appliques et approche du developpement d'une culture pratique de l'evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Broc, J S

    2006-12-15

    Energy end-use Efficiency (EE) is a priority for energy policies to face resources exhaustion and to reduce pollutant emissions. At the same time, in France, local level is increasingly involved into the implementation of EE activities, whose frame is changing (energy market liberalization, new policy instruments). Needs for ex-post evaluation of the local EE activities are thus increasing, for regulation requirements and to support a necessary change of scale. Our thesis focuses on the original issue of the ex-post evaluation of local EE operations in France. The state of the art, through the analysis of the American and European experiences and of the reference guidebooks, gives a substantial methodological material and emphasises the key evaluation issues. Concurrently, local EE operations in France are characterized by an analysis of their environment and a work on their segmentation criteria. The combination of these criteria with the key evaluation issues provides an analysis framework used as the basis for the composition of evaluation methods. This also highlights the specific evaluation needs for local operations. A methodology is then developed to complete and adapt the existing material to design evaluation methods for local operations, so that stakeholders can easily appropriate. Evaluation results thus feed a know-how building process with experience feedback. These methods are to meet two main goals: to determine the operation results, and to detect the success/failure factors. The methodology was validated on concrete cases, where these objectives were reached. (author)

  11. Ex-post evaluation of local energy efficiency and demand-side management operations - State of the art, bottom-up methods, applied examples and approach for the development of an evaluation practical culture; L'evaluation ex-post des operations locales de maitrise de la demande en energie - Etat de l'art, methodes bottom-up, exemples appliques et approche du developpement d'une culture pratique de l'evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Broc, J.S

    2006-12-15

    Energy end-use Efficiency (EE) is a priority for energy policies to face resources exhaustion and to reduce pollutant emissions. At the same time, in France, local level is increasingly involved into the implementation of EE activities, whose frame is changing (energy market liberalization, new policy instruments). Needs for ex-post evaluation of the local EE activities are thus increasing, for regulation requirements and to support a necessary change of scale. Our thesis focuses on the original issue of the ex-post evaluation of local EE operations in France. The state of the art, through the analysis of the American and European experiences and of the reference guidebooks, gives a substantial methodological material and emphasises the key evaluation issues. Concurrently, local EE operations in France are characterized by an analysis of their environment and a work on their segmentation criteria. The combination of these criteria with the key evaluation issues provides an analysis framework used as the basis for the composition of evaluation methods. This also highlights the specific evaluation needs for local operations. A methodology is then developed to complete and adapt the existing material to design evaluation methods for local operations, so that stakeholders can easily appropriate. Evaluation results thus feed a know-how building process with experience feedback. These methods are to meet two main goals: to determine the operation results, and to detect the success/failure factors. The methodology was validated on concrete cases, where these objectives were reached. (author)

  12. New developments in the analysis and measurement of thicknesses by {beta}-particle excitation of X fluorescent rays; Nouveaux developpements de l'analyse et de la mesure des epaisseurs par excitation des raies de fluorescence X au moyen de particules {beta}; Novye usovershenstvovaniya analiza i izmereniya plotnosti putem vozbuzhdeniya fluorestsiruyushchikh spektrov rentgenovskogo lucha beta-chastitsami; Nuevos adelantos en el analisis y la medicion de espesores mediante la excitacion de rayos X por particulas beta

    Energy Technology Data Exchange (ETDEWEB)

    Martinelli, P [Commissariat a l' Energie Atomique, Saclay (France); Seibel, G [Institut de Recherches de la Siderurgie, St-Germain-en-Laye (France)

    1962-01-15

    The method of analysing and measuring the thickness of deposits by {beta}-X fluorescence which we previously described has been further developed. Using Pm{sup 147} and Kr{sup 85} sources, it is possible to reduce the background observed with Sr{sup 90}. We quote the results obtained for various thickness measurements of metal deposits, an analysis of the solutions, and the continuous measurement of calcium and iron in core samples. We describe experiments made for analysis of the X-radiation by crystal. (author) [French] Le procede d'analyse et de mesure des epaisseurs de depots par fluorescence {beta}-X que nous avons precedemment decrit a fait l'objet de nouveaux developpements. L'emploi de sources de {sup 147}Pm et de {sup 85}Kr permet de reduire le bruit de fond que l'on observe avec le {sup 90}Sr. Nous donnons les resultats obtenus pour diverses mesures d'epaisseurs de depots metalliques, l'analyse des solutions et la mesure en continu du calcium et du fer dans les carottes de minerais. Nous decrivons les essais effectues en vue d'analyser le rayonnement X au moyen d'un cristal. (author) [Spanish] Los autores han introducido nuevos perfeccionamientos en su procedimiento de analisis y de medicion de espesores de depositos por fluorescencia de rayos X excitada por particulas beta. La utilizacion de fuentes de {sup 147}Pm y de {sup 85}Kr permite reducir la actividad de fondo que se observa empleando {sup 90}Sr. Los autores exponen los resultados obtenidos en materia de mediciones de espesores de depositos metalicos, analisis de soluciones y medicion continua del calcio y del hierro en muestras de minerales extraidas por sondeo. Tambien describen los ensayos realizados con miras a analizar los rayos X por medio de un cristal. (author) [Russian] Protsess analiza i izmereniya plotnosti sloev putem fluorestsiruyushchikh beta- i rentgenovskikh luchej, kotoryj opisyvalsya nami ran'she, byl predmetom novykh usovershenstvovanij. Ispol'zovanie istochnikov prometeya-147 i

  13. New developments in the analysis and measurement of thicknesses by excitation of the fluorescent lines by means of {beta} particles; Nouveaux developpements de l'analyse et de la mesure des epaisseurs par excitation des raies de fluorescence au moyen de particules {beta}

    Energy Technology Data Exchange (ETDEWEB)

    Martinelli, P [Commissariat a l' Energie Atomique, Saclay (France).Centre d' Etudes Nucleaires; Seibel, G [Institut de Recherches de la Siderurgie, 78 - Saint-Germain-en-Laye (France)

    1960-07-01

    The process for analysing and measuring the thickness of deposits by {beta}-X fluorescence which we have already described has undergone further development. The use of promethium-147 and krypton-85 sources makes it possible to reduce the background noise which is observed with strontium-90. We present the results obtained for various measurements of the thickness of metallic coatings and the continuous measurement of calcium and of iron in ore samples. We describe the tests carried out with a view to analysing the X-rays by means of a crystal. (author) [French] Le procede d'analyse et de mesure des epaisseurs de depots par fluorescence {beta}-X que nous avons precedemment decrit a fait l'objet de nouveaux developpements. L'emploi de sources de prometheum-147 et de krypton-85 permet de reduire le bruit de fond que l'on observe avec le strontium-90. Nous dormons les resultats obtenus pour diverses mesures d'epaisseurs de depots metalliques et la mesure en continu du calcium et du fer dans les carottes de minerais. Nous decrivons les essais effectues en vue d'analyser le rayonnement X au moyen d'un cristal. (auteur)

  14. Methods and tools in development in the field of maintenance; Methodes et outils pour la maintenance en cours de developpement

    Energy Technology Data Exchange (ETDEWEB)

    Le Reverend, D.; Tortolano, M. [Electricite de France (EDF/RD), 78 - Chatou (France); Leniaud, F. [Electricite de France (EDF), Div. Production Nuleaire, 93 - Saint-Denis (France)

    2004-07-01

    This article is dedicated to the maintenance strategy followed by EDF for its nuclear power plants. This strategy is based on the American method RCM (reliability centered method) that has been extended to passive components such as structures and relies on 4 axis. The first axis can be defined as the optimization of maintenance with regard to safety, outage and costs. The aim is to set the border between preventive maintenance and remedial maintenance. The second axis is the condition based maintenance that is the maintenance action that is triggered by the real state of the equipment. This type of maintenance implies the search for reliable and accurate diagnostics. The third axis is the design of simulation and planning tools required for the management of the moving of tools, machinery and spare-parts on a maintenance work site. The fourth axis is the design of tools able to repair some important equipment, this way may be a valid alternative to the replacement of equipment in terms of cost and outage time. (A.C.)

  15. The grand partition function Z ({alpha},{beta}) of a quantum system is studied, using diagrammatic representations of the perturbation expansion; La grande fonction de partition Z ({alpha},{beta}) d'un systeme quantique est etudies en utilisant des representations diagrammatiques du developpement en serie des perturbations

    Energy Technology Data Exchange (ETDEWEB)

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

    1961-07-01

    The grand partition function Z ({alpha},{beta}) of a quantum system is studied, using diagrammatic representations of the perturbation expansion. For a fermions system, it is possible to show, by proper resummation, without approximations but under some 'regularity hypothesis', that Log Z ({alpha},{beta}) takes a form where, besides trivial dependences, {alpha} and {beta} only appear through a statistical factor F{sub k}{sup -} = [1 + e{sup -{alpha}}{sup +{beta}}{sup {epsilon}{sub k}{sup 0}}{sup -{beta}}{sup W{sub k}}]{sup -1}. W{sub k} is a (real) self-consistent potential, generalized to all orders and can be defined by a stationary condition on Log Z ({alpha},{beta}) under variations of F{sub k}{sup -}. The thermodynamical quantities take a form analogous to the expressions Landau introduced for the Fermi liquids. The zero temperature limit (for isotropic systems) gives back Goldstone expressions for the ground state of a system. (author) [French] La grande fonction de partition Z ({alpha},{beta}) d'un systeme quantique est etudiee en utilisant des representations diagrammatiques du developpement en serie des perturbations. Pour un systeme de fermions on peut, par des resommations adequates, sans approximations mais sous reserve d'une 'hypothese de regularite', mettre Log Z ({alpha},{beta}) sous une forme ou, en dehors de dependances triviales, {alpha} et {beta} n'interviennent que par l'intermediaire d'un facteur statistique F{sub k}{sup -} = [1 + e{sup -{alpha}}{sup +{beta}}{sup {epsilon}{sub k}{sup 0}}{sup -{beta}}{sup W{sub k}}]{sup -1}. W{sub k} est ici un potentiel self-consistant (reel) generalise a tous les ordres et peut etre defini par une condition de stationnarite de Log Z ({alpha},{beta}) pour des variations de F{sub k}{sup -}. Les grandeurs thermodynamiques prennent une forme analogue aux expressions que LANDAU a introduites pour les liquides de FERMI. A la limite de la temperature nulle (et pour un

  16. The grand partition function Z ({alpha},{beta}) of a quantum system is studied, using diagrammatic representations of the perturbation expansion; La grande fonction de partition Z ({alpha},{beta}) d'un systeme quantique est etudies en utilisant des representations diagrammatiques du developpement en serie des perturbations

    Energy Technology Data Exchange (ETDEWEB)

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

    1961-07-01

    The grand partition function Z ({alpha},{beta}) of a quantum system is studied, using diagrammatic representations of the perturbation expansion. For a fermions system, it is possible to show, by proper resummation, without approximations but under some 'regularity hypothesis', that Log Z ({alpha},{beta}) takes a form where, besides trivial dependences, {alpha} and {beta} only appear through a statistical factor F{sub k}{sup -} = [1 + e{sup -{alpha}}{sup +{beta}}{sup {epsilon}{sub k}{sup 0}}{sup -{beta}}{sup W{sub k}}]{sup -1}. W{sub k} is a (real) self-consistent potential, generalized to all orders and can be defined by a stationary condition on Log Z ({alpha},{beta}) under variations of F{sub k}{sup -}. The thermodynamical quantities take a form analogous to the expressions Landau introduced for the Fermi liquids. The zero temperature limit (for isotropic systems) gives back Goldstone expressions for the ground state of a system. (author) [French] La grande fonction de partition Z ({alpha},{beta}) d'un systeme quantique est etudiee en utilisant des representations diagrammatiques du developpement en serie des perturbations. Pour un systeme de fermions on peut, par des resommations adequates, sans approximations mais sous reserve d'une 'hypothese de regularite', mettre Log Z ({alpha},{beta}) sous une forme ou, en dehors de dependances triviales, {alpha} et {beta} n'interviennent que par l'intermediaire d'un facteur statistique F{sub k}{sup -} = [1 + e{sup -{alpha}}{sup +{beta}}{sup {epsilon}{sub k}{sup 0}}{sup -{beta}}{sup W{sub k}}]{sup -1}. W{sub k} est ici un potentiel self-consistant (reel) generalise a tous les ordres et peut etre defini par une condition de stationnarite de Log Z ({alpha},{beta}) pour des variations de F{sub k}{sup -}. Les grandeurs thermodynamiques prennent une forme analogue aux expressions que LANDAU a introduites pour les liquides de FERMI. A la limite de la temperature nulle (et pour un systeme isotrope) on retrouve terme a terme les

  17. Optimisation des trajectoires verticales par la methode de la recherche de l'harmonie =

    Science.gov (United States)

    Ruby, Margaux

    Face au rechauffement climatique, les besoins de trouver des solutions pour reduire les emissions de CO2 sont urgentes. L'optimisation des trajectoires est un des moyens pour reduire la consommation de carburant lors d'un vol. Afin de determiner la trajectoire optimale de l'avion, differents algorithmes ont ete developpes. Le but de ces algorithmes est de reduire au maximum le cout total d'un vol d'un avion qui est directement lie a la consommation de carburant et au temps de vol. Un autre parametre, nomme l'indice de cout est considere dans la definition du cout de vol. La consommation de carburant est fournie via des donnees de performances pour chaque phase de vol. Dans le cas de ce memoire, les phases d'un vol complet, soit, une phase de montee, une phase de croisiere et une phase de descente, sont etudies. Des " marches de montee " etaient definies comme des montees de 2 000ft lors de la phase de croisiere sont egalement etudiees. L'algorithme developpe lors de ce memoire est un metaheuristique, nomme la recherche de l'harmonie, qui, concilie deux types de recherches : la recherche locale et la recherche basee sur une population. Cet algorithme se base sur l'observation des musiciens lors d'un concert, ou plus exactement sur la capacite de la musique a trouver sa meilleure harmonie, soit, en termes d'optimisation, le plus bas cout. Differentes donnees d'entrees comme le poids de l'avion, la destination, la vitesse de l'avion initiale et le nombre d'iterations doivent etre, entre autre, fournies a l'algorithme pour qu'il soit capable de determiner la solution optimale qui est definie comme : [Vitesse de montee, Altitude, Vitesse de croisiere, Vitesse de descente]. L'algorithme a ete developpe a l'aide du logiciel MATLAB et teste pour plusieurs destinations et plusieurs poids pour un seul type d'avion. Pour la validation, les resultats obtenus par cet algorithme ont ete compares dans un premier temps aux resultats obtenus suite a une recherche exhaustive qui a

  18. Optical Density Control of Autoradiographs After Photographic Processing (Preliminary Results); Controle de la Densite Optique des Autoradiogrammes Apres Developpement Photographique. (Resultats Preliminaires); Regulirovanie opticheskoj plotnosti avtoradiogramm posle fotoobrabotki; Control de la Densidad Optica de las Autorradiografias Despues del Tratamiento Fotografico. (Resultados Preliminares)

    Energy Technology Data Exchange (ETDEWEB)

    Baptista, A. M. [Comissao de Estudos de Energia Nuclear, Instituto de Alta Cultura, Lisbon (Portugal); Terrinha, A. [Instituto Portugues de Oncologia, Lisbon (Portugal)

    1965-10-15

    In many applications of photographic emulsions it would be desirable to control the optical density after the photographic processing. This would be useful for instance in certain problems of photographic dosimetry and particularly in many applications of autoradiography in medicine and biology. It would then be possible to recover information lost by overexposure as it frequently occurs unavoidably particularly in cases where important grain density variations are observed in the same autoradiograph specimen. The authors report the first results of an attempt to control the grain density after development and fixation of the photographic material by attacking the processed emulsion with diluted solutions of trypsin. By changing concentrations and temperature the attack can be made to proceed at any desirable speed so the trypsin solution acts like an ultra microtome removing very thin layers of the photographic emulsion. More important, the process could be followed continuously under the microscope by using a suitable chamber. Results are presented which suggest that this technique can give a rough idea of the incorporation with time of the radionuclide in the biological structure under observation. (author) [French] Dans diverses applications d'emulsions photographiques, il serait souhaitable de controler la densite optique apres avoir procede au developpement. Cette methode serait utile, par exemple pour resoudre certains problemes de dosimetrie photographique, et notamment dans maintes applications medicales et biologiques de l'autoradiographie. Il serait alors possible de recuperer les indications perdues en raison d'une surexposition, souvent inevitable, surtout dans les cas ou la densite du grain varie tres sensiblement dans un meme specimen autoradiographique. Les auteurs signalent les premiers resultats qu'ils ont pu obtenir en cherchant a controler la densite du grain, apres developpement et fixation de la substance photographique, en attaquant l

  19. Study and development of an optical method for the measurement of convection coefficients; Etude et developpement d'une methode optique pour la mesure du coefficient de convection

    Energy Technology Data Exchange (ETDEWEB)

    Crowther, David J.

    1990-03-06

    This research thesis addresses the field of fluid-wall thermal exchanges in which the notion of exchange coefficient is notably useful to design, size and optimise devices. A first part reports a bibliographical study which gives an overview of solutions envisaged to determine the convection coefficient in permanent regime with the use of flow sensors, as well as in transient regime. Then, the author reports the development of an unsteady method which is based on the analysis of the cooling kinetics of the front face of a convecting wall, after a unique energetic perturbation (an infinitely brief pulse, or a finite duration energy step). This method is applied to the general case (wall with finite thickness) and to the case of a semi-infinite wall which is typical of materials which are weak thermal conductors. This is extended to the case of good thermal conductors by considering a thermally thin wall. After a detailed description of the experimental bench, above-mentioned solutions are applied to insulating and good thermal conducting materials. In order to validate results of an analysis in transient regime, they are compared with measurements performed in permanent regime with a flow-metering technique. The study of the principle of the dissipation-based flow sensor, and its operation are reported. Experimental results are presented for both methods (pulse and flow sensor), and compared in order to highlight the interest of the unsteady method [French] Difficile a mesurer, le coefficient de convection reste cependant une grandeur necessaire au calcul et a l'optimisation de tout systeme thermique. L'amelioration des capteurs thermiques permet aujourd'hui de concevoir une methode optique, utilisable a distance, et non destructive. Nous proposons dans ce but, un procede de mesure en regime transitoire base sur la radiometrie photothermique impulsionnelle. L'analyse du regime de relaxation d'une paroi, apres une brusque elevation de temperature, permet de remonter

  20. Quebec energy development in a sustainable development context; Le developpement energetique du Quebec dans un contexte de developpement durable

    Energy Technology Data Exchange (ETDEWEB)

    Laplatte, Benjamin; Bourque, Francis; Granger, Francois P.

    2010-09-15

    Quebec is a net importer of oil and it is clear that the reduction of its dependence with regards to hydrocarbons must be a main preoccupation. Moreover, the energy consumption per habitant of Quebec is higher than that of the majority of the other developed countries. This analysis looks at the choice on offer to the society of the province of Quebec, in terms of energy resources and technologies of today and tomorrow, in a context of sustainable development. [French] Le Quebec est un importateur net de petrole et il est clair que la reduction de sa dependance a l'egard des hydrocarbures doit etre une preoccupation de premier plan. De plus, la consommation energetique par habitant du Quebec est plus elevee que celle de la majorite des autres pays developpes. La presente analyse adresse les choix qui s'offrent a la societe quebecoise, en matiere de ressources et de technologies de l'energie d'aujourd'hui et de demain, dans un contexte de developpement durable.

  1. Developpement et evaluation d'un environnement informatise d'apprentissage pour faciliter l'integration des sciences et de la technologie

    Science.gov (United States)

    Saliba, Marie-Therese

    2011-12-01

    Through this research we will fully assess the benefits brought by the ExAO (Computer Assisted Experimentation) in school laboratories of science and technology in Lebanon. We would also like to mention its contribution in a tangible way in laboratory research of Pedagogic Robotic from Montreal University, particularly in the development of ExAO mulaboratory. We wanted to test the capabilities of the ExAO, its use in the classroom such as: 1. A replacement of a traditional laboratory in the use of the experimental method. 2. A scientific investigation tool. 3. An integration tool of experimental sciences and mathematics. 4. An integration tool of experimental sciences, mathematics and technology in the technoscientific learning. To do so, we have mobilized 13 group classes, designated teachers to experiment themselves along with their students in order to assess, in a more realistic way, the benefits of implementing this micro computer laboratory at school. Different testing, evaluated using the results of learning activities undertaken by students, their responses to a questionnaire and feedback from teachers, show that: 1. The replacement of a traditional laboratory with an ExAO mulaboratory does not seem to pose problem, expected that students have adapted to it in only ten minutes, indicating that the speed with which data were graphed was more productive. 2. In order to investigate a physical phenomenon, the usability of the tutorial associated with the ability to amplify the phenomenon before its graph representation, has allowed students to design and implement quickly and independently an experiment to verify their prediction. 3. The integration of mathematics into an experimental approach can quickly grasp the phenomenon. In addition, it gives more autonomy and a meaning to the graphs and algebraic representations allowing to use them as a cognitive tool to interpret this phenomenon. 4. The approach made by the students to design and construct a

  2. Planification optimisee des reseaux electriques par la methode des ...

    African Journals Online (AJOL)

    In this paper, the insertion of renewable power sources (wind, solar photovoltaic, hydroelectric) in an existing electrical system was planned by the method of genetic algorithms in real coding. The main objective of this planning is the optimization of production costs of these renewable energy sources and electric power ...

  3. Development of the control assembly pattern and dynamic analysis of the generation IV large gas-cooled fast reactor (GFR); Developpement du design d'un assemblage de controle et analyse dynamique des reacteurs a neutrons rapides de quatrieme generation refroidis au gaz

    Energy Technology Data Exchange (ETDEWEB)

    Girardin, G.

    2009-07-09

    was paid to have each individual fuel sub-assembly and CA represented, in order to allow the analysis of local deformations of the 3D distributions of power and safety related parameters, such as the coolant, cladding and fuel temperatures. The validation of the coupled full core models was performed against reference ERANOS-VARIANT calculations. (author) [French] Le travail de recherche a ete mene dans le contexte du RNR-G de reference a 2400 MWth. Le but principal a ete de developper et de qualifier le design de l'assemblage de controle et le schema d'implantation correspondant a ce systeme. Le travail a ete realise en trois phases successives et complementaires: (1) la validation des outils neutroniques, (2) le developpement du design de l'assemblage de controle et les etudes statiques correspondantes, (3) les etudes du comportement dynamique du coeur durant des transitoires hypothetiques lies aux assemblages de controle. Pendant la premiere phase de la these, le reseau test de reference de PROTEUS utilise dans ces experiences, a ete reinterprete avec ERANOS et la bibliotheque nucleaire ajustee ERALIB1. De maniere complementaire, des calculs de references ont ete realises avec le code de Monte Carlo MCNPX, visant a verifier les resultats deterministes, et a analyser la sensibilite des resultats aux differentes modernes librairies. Pour les taux de reactions principaux, la nouvelle analyse du reseau de reference GCFR-PROTEUS donne generalement des resultats en bon accord - dans l'incertitude experimentale 1{sigma} - avec les resultats experimentaux, ainsi qu'avec les simulations de Monte Carlo. L'utilisation d'ERANOS-2.0/ERALIB1 comme outil neutronique de reference a ainsi pu etre demontree pour l'analyse du RNR-G. Dans une seconde phase de cette recherche, le design de l'assemblage de controle (AC) du GFR a ete developpe, base sur des calculs a caractere iteratif, neutroniques et thermo-hydrauliques. En premier, des

  4. Developpement et implementation d'une methode pour resoudre les equations de la couche limite laminaire et turbulente

    Science.gov (United States)

    Leuca, Maxim

    CFD (Computational Fluid Dynamics) is a computational tool for studying flow in science and technology. The Aerospace Industry uses increasingly the CFD modeling and design phase of the aircraft, so the precision with which phenomena are simulated boundary layer is very important. The research efforts are focused on optimizing the aerodynamic performance of airfoils to predict the drag and delay the laminar-turbulent transition. CFD codes must be fast and efficient to model complex geometries for aerodynamic flows. The resolution of the boundary layer equations requires a large amount of computing resources for viscous flows. CFD codes are commonly used to simulate aerodynamic flows, require normal meshes to the wall, extremely fine, and, by consequence, the calculations are very expensive. . This thesis proposes a new approach to solve the equations of boundary layer for laminar and turbulent flows using an approach based on the finite difference method. Integrated into a code of panels, this concept allows to solve airfoils avoiding the use of iterative algorithms, usually computing time and often involving convergence problems. The main advantages of panels methods are their simplicity and ability to obtain, with minimal computational effort, solutions in complex flow conditions for relatively complicated configurations. To verify and validate the developed program, experimental data are used as references when available. Xfoil code is used to obtain data as a pseudo references. Pseudo-reference, as in the absence of experimental data, we cannot really compare two software together. Xfoil is a program that has proven to be accurate and inexpensive computing resources. Developed by Drela (1985), this program uses the method with two integral to design and analyze profiles of wings at low speed (Drela et Youngren, 2014), (Drela, 2003). NACA 0012, NACA 4412, and ATR-42 airfoils have been used for this study. For the airfoils NACA 0012 and NACA 4412 the calculations

  5. Developpement of a numerical method for Navier-Stokes equations in anelastic approximation: application to Rayleigh-Taylor instabilities

    International Nuclear Information System (INIS)

    Hammouch, Z.

    2012-01-01

    The 'anelastic' approximation allows us to filter the acoustic waves thanks to an asymptotic development of the Navier-Stokes equations, so increasing the averaged time step, during the numerical simulation of hydrodynamic instabilities development. So, the anelastic equations for a two fluid mixture in case of Rayleigh-Taylor instability are established.The linear stability of Rayleigh-Taylor flow is studied, for the first time, for perfect fluids in the anelastic approximation. We define the Stokes problem resulting from Navier-Stokes equations without the non linear terms (a part of the buoyancy is considered); the ellipticity is demonstrated, the Eigenmodes and the invariance related to the pressure are detailed. The Uzawa's method is extended to the anelastic approximation and shows the decoupling speeds in 3D, the particular case k = 0 and the spurious modes of pressure. Passing to multi-domain allowed to establish the transmission conditions.The algorithms and the implementation in the existing program are validated by comparing the Uzawa's operator in Fortran and Mathematica languages, to an experiment with incompressible fluids and results from anelastic and compressible numerical simulations. The study of the influence of the initial stratification of both fluids on the development of the Rayleigh-Taylor instability is initiated. (author) [fr

  6. Diagnosis of water pollution caused by chemical effluents using hydro biological methods; Diagnostic de la pollution des eaux par les effluents chimiques au moyen des methodes hydrobiologiques

    Energy Technology Data Exchange (ETDEWEB)

    Simeon, C; Bonnefoy-Claudet, J [Commissariat a l' Energie Atomique, Pierrelatte (France). Centre d' Etudes Nucleaires

    1965-04-01

    ont modifie le systeme des Saprobies de Kolwickz. Ils ont essaye de deceler la presence ou l'absence de pollution en evaluant la densite du phytoplancton, se developpant sur des lames immergees (periphyton) et les variations specifiques des algues constituant ces populations. Ce sont ces essais et les premiers resultats obtenus qui figurent dans ce rapport. (auteurs)

  7. Diagnosis of water pollution caused by chemical effluents using hydro biological methods; Diagnostic de la pollution des eaux par les effluents chimiques au moyen des methodes hydrobiologiques

    Energy Technology Data Exchange (ETDEWEB)

    Simeon, C.; Bonnefoy-Claudet, J. [Commissariat a l' Energie Atomique, Pierrelatte (France). Centre d' Etudes Nucleaires

    1965-04-01

    'experience et ont modifie le systeme des Saprobies de Kolwickz. Ils ont essaye de deceler la presence ou l'absence de pollution en evaluant la densite du phytoplancton, se developpant sur des lames immergees (periphyton) et les variations specifiques des algues constituant ces populations. Ce sont ces essais et les premiers resultats obtenus qui figurent dans ce rapport. (auteurs)

  8. Report on the actions fostering renewable energy sources; Bilan des actions conduites par Christian Pierret, Secretaire d'Etat a l'Industrie en faveur du developpement des energies renouvelables

    Energy Technology Data Exchange (ETDEWEB)

    Pierret, Christian [State Secretary for Industry, French Government, Paris (France)

    1999-06-15

    The principal renewable energy source of France is, after hydro-power, the wood fuels, the 9.1 Mtep production rate of which exceeds the cumulated coal, gas and oil national productions. The plan 'Wood-energy and Local Development', launched in 1994, resulting in the installation of 168 boilers at a 150 MW total power and consuming 36,000 tep/y, was followed by the plan 'Wood-Wastes', announced by Christian Pierret on February 1998, aiming at boosting the energetic use of wood wastes. In the wind power sector a program EOLE 2005 was launched having as goal installing in France up to 2005 a wind power capacity of 250 to 500 MW. 20 projects with a total capacity of 77.5 MW were selected. Under EOLE 2005 provisions there is a 125.3 MW wind power capacity to be installed up to the end of year 2000. A new call for propositions aiming at up to 100 MW wind power capacity was asked from EDF by the secretary of state Mr Christian Pierret. In the field of thermal solar energy a program titled '20,000 solar boilers in the overseas territories (DOM)' has as objective the installation in 5 years of 20,000 solar boilers in the Antilles, Guiana and Reunion. These means of generating sanitary hot water are actually well-fitted to the climate of these regions where the cost of competing electricity is rather high. By January 1999 almost 15,000 solar boilers were installed in the frame of this program. The large scale production of these units resulted already in a 30% decrease in their price. A new 30 MF/yr program HELIOS 2006 was initiated to boost the development of the solar boilers. Since 1995, under the frame of 'Fonds d'Amortissement des charges d'Electrification' (FACE), a 100 MF project was launched to finance actions of energy management and promote decentralized installations for electricity production from renewable energy sources. These efforts are aimed at fulfilling the electricity needs of isolated sites. By the end

  9. Law project on the gas utility modernization and gas industries development. Law project synthesis on the gas utility modernization and gas industries development; Projet de loi relatif a la modernisation du service public du gaz naturel et au developpement des entreprises gazieres.Synthese du projet de loi sur la modernisation du service public du gaz et le developpement des entreprises gazieres

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-05-01

    The french government would like to develop a law concerning the gas utility modernization and gas industries development, which completes the today system, more particularly, the law of 1946. This project specifies and comforts the gas utility, it gives to the energy policy tools adapted to the new european context. It helps the natural gas industry to become more competitive. The method chosen by the government is presented and discussed in these three documents. (A.L.B.)

  10. Methodes de calcul des forces aerodynamiques pour les etudes des interactions aeroservoelastiques

    Science.gov (United States)

    Biskri, Djallel Eddine

    L'aeroservoelasticite est un domaine ou interagissent la structure flexible d'un avion, l'aerodynamique et la commande de vol. De son cote, la commande du vol considere l'avion comme une structure rigide et etudie l'influence du systeme de commande sur la dynamique de vol. Dans cette these, nous avons code trois nouvelles methodes d'approximation de forces aerodynamiques: Moindres carres corriges, Etat minimal corrige et Etats combines. Dans les deux premieres methodes, les erreurs d'approximation entre les forces aerodynamiques approximees par les methodes classiques et celles obtenues par les nouvelles methodes ont les memes formes analytiques que celles des forces aerodynamiques calculees par LS ou MS. Quant a la troisieme methode, celle-ci combine les formulations des forces approximees avec les methodes standards LS et MS. Les vitesses et frequences de battement et les temps d'executions calcules par les nouvelles methodes versus ceux calcules par les methodes classiques ont ete analyses.

  11. Prognosis, prospecting and development of gas fields in the far north of Siberia - as a single methodological approach to an optimal development of the territorial resources; Prevision, prospection et developpement des champs de gaz naturel du grand nord Siberien - approche methodologique unique pour un developpement optimal des ressources du territoire

    Energy Technology Data Exchange (ETDEWEB)

    Remizov, V.V.; Dmitrievsky, A.N.; Ermilov, O.M.; Neelov, Y.V.; Chugunov, L.S.; Gurari, F.G.; Goldin, S.V.; Karagodin, Y.N. [OJSC Gaprom, Russian Academy of Sciences (Russian Federation)

    2000-07-01

    This presentation realizes a systems approach to the study of the oil and gas complex of the Far North of Siberia as a single sophisticated system starting from prognosis and prospecting of fields to their development at different stages of operation. This paper shows for the first time the whole complex of studies, including the methodology of systems studies of the structure, evolution and genesis of oil and gas reservoirs, the model of geologic structure and the evaluation of oil and gas resources, the technique of prospecting and surveys of oil and gas fields, techniques and methods of an effective system of prospecting and development, particularly at the stage of achieving maximum and the onset of production decrease. (authors)

  12. Localized corrosion of carbon steels due to sulfate-reducing bacteria. Development of a specific sensor; Corrosion localisee des aciers au carbone induite par des bacteries sulfato-reductrices. Developpement d'un capteur specifique

    Energy Technology Data Exchange (ETDEWEB)

    Monfort Moros, N.

    2001-11-01

    This work concerns the microbiologically influenced corrosion of carbon steels in saline anaerobic media (3% of NaCl) containing sulfato-reducing bacteria (Desulfovibrio gabonensis, DSM 10636). In these media, extreme localised corrosion occurs by pitting under the bio-film covering the metallic substrate. A sensor with concentric electrodes was designed to initiate the phenomenon of bio-corrosion, recreating the favourable conditions for growth of a corrosion pit, and then measuring the corrosion current maintained by bacterial activity. The pit initiation was achieved through either of two methods. The electrochemical conditioning involved driving the potential difference between inner and outer electrodes to values corresponding to a galvanic corrosion that can be maintained by the bacterial metabolism. The mechanical process involved removal of a portion of the bio-film by scratching, yielding galvanic potential differences equivalent to that found by the conditioning technique. This protocol was found to be applicable to a bio-corrosion study on industrial site for the monitoring of the metallic structures deterioration (patent EN 00/06114, May 2000). Thereafter, a fundamental application uses the bio-corrosion sensor for Electrochemical Impedance Spectroscopy (EIS), Electrochemical Noise Analysis (ENA) and current density cartography by the means of micro-electrodes. Thus, the EIS technique reveals the importance of the FeS corrosion products for initiation of bio-corrosion start on carbon steel. In addition, depending on the method used to create a pit, the ENA gives rise to supplementary processes (gaseous release) disturbing the bio-corrosion detection. The beginning of a bio-corrosion process on a clean surface surrounded with bio-film was confirmed by the current density cartography. These different results establish the sensor with concentric electrodes as an indispensable tool for bio-corrosion studies, both in the laboratory and on industrial sites

  13. Improvements in fast-neutron spectroscopy methods (1961); Amelioration des methodes de spectrometrie des neutrons rapides (1961)

    Energy Technology Data Exchange (ETDEWEB)

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

    1961-02-15

    This research aimed at improving fast-neutron electronic detectors based on n-p elastic scattering. The first part concerns proportional counters; careful constructional methods have made it possible to plot mono-energetic neutron spectra in the range 700 keV - 3 MeV with a resolution of 7 per cent. The second part concerns scintillation counters: an organic scintillator and an inorganic scintillator covered with a thin layer of a scattering agent. An exact study of the types of scintillation has made it possible to develop efficient discriminator circuits. Different neutron spectra plotted in the presence of a strong gamma background are presented. The last part deals with the development of form discrimination methods for the study, in the actual beam, of the elastic scattering of 14.58 MeV electrons. With hydrogen, the distribution f ({phi}) of the recoil protons is f({phi}) = 1 + 0.034 cos {phi} + 0.042 cos{sup 2} {phi}. With tritium the scattering is strongly anisotropic; the curve representing the variation of the differential cross-section for the elastic scattering in the centre of mass system is obtained with a target containing 1 cm{sup 3} of tritium. (author) [French] Le travail a porte sur l'amelioration des detecteurs electroniques de neutrons rapides bases sur la diffusion elastique n-p. La premiere partie est relative aux compteurs proportionnels; des methodes soignees de fabrication ont permis des traces de spectres de neutrons monoenergetiques dans le domaine 700 keV - 3 MeV avec une resolution de 7 pour cent. La deuxieme partie est relative au compteur a scintillations; scintillateur organique et scintillateur mineral recouvert d'un diffuseur mince. Une etude precise des formes de scintillations a permis la mise au point de circuits discriminateurs efficaces. Differents spectres de neutrons traces en presence d'un fond gamma intense sont presentes. La derniere partie est relative a la mise en oeuvre des methodes de discrimination de forme pour l

  14. Techniques d'inspection par ondes guidees ultrasonores d'assemblages brases dans des reacteurs aeronautiques =

    Science.gov (United States)

    Comot, Pierre

    L'industrie aeronautique, cherche a etudier la possibilite d'utiliser de maniere structurelle des joints brases, dans une optique de reduction de poids et de cout. Le developpement d'une methode d'evaluation rapide, fiable et peu couteuse pour evaluer l'integrite structurelle des joints apparait donc indispensable. La resistance mecanique d'un joint brase dependant principalement de la quantite de phase fragile dans sa microstructure. Les ondes guidees ultrasonores permettent de detecter ce type de phase lorsqu'elles sont couplees a une mesure spatio-temporelle. De plus la nature de ce type d'ondes permet l'inspection de joints ayant des formes complexes. Ce memoire se concentre donc sur le developpement d'une technique basee sur l'utilisation d'ondes guidees ultrasonores pour l'inspection de joints brases a recouvrement d'Inconel 625 avec comme metal d'apport du BNi-2. Dans un premiers temps un modele elements finis du joint a ete utilise pour simuler la propagation des ultrasons et optimiser les parametres d'inspection, la simulation a permis egalement de demontrer la faisabilite de la technique pour la detection de la quantite de phase fragile dans ce type de joints. Les parametres optimises sont la forme de signal d'excitation, sa frequence centrale et la direction d'excitation. Les simulations ont montre que l'energie de l'onde ultrasonore transmise a travers le joint aussi bien que celle reflechie, toutes deux extraites des courbes de dispersion, etaient proportionnelles a la quantite de phase fragile presente dans le joint et donc cette methode permet d'identifier la presence ou non d'une phase fragile dans ce type de joint. Ensuite des experimentations ont ete menees sur trois echantillons typiques presentant differentes quantites de phase fragile dans le joint, pour obtenir ce type d'echantillons differents temps de brasage ont ete utilises (1, 60 et 180 min). Pour cela un banc d'essai automatise a ete developpe permettant d'effectuer une analyse similaire

  15. Application of general methods for the study of porous materials to the determination of the characteristics of barriers; Application des methodes generales d'etudes des corps poreux a la determination des caracteristiques des barrieres

    Energy Technology Data Exchange (ETDEWEB)

    Plurien, P; Charpin, J; Mommejac, S [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1958-07-01

    Barriers foreseen for the separation of uranium isotopes by gaseous diffusion must posses pores of about 100 Angstrom radius and as high an output as possible. They should thus be of small but uniform thickness. In view of these conditions it is necessary to adapt the normal methods available for studying porous materials in order to check the characteristics of the prototypes examined. It has been found that only by cross-comparison of data from various methods can progress in the development of different prototypes be followed. The following account consists of two parts: 1) A review of the main experimental methods we have used: a) various absorption methods, b) electron microscopy, c) X-ray studies, d) mercury porosimetry, e) liquid permeability, f) gas permeability, g) measurement of separation efficiency. 2) Comparison of the results obtained using these various methods and their application with a view to acquiring as complete a knowledge as possible of the structure of the barrier. (author) [French] Les barrieres susceptibles d'etre utilisees pour la separation des isotopes de l'uranium, par diffusion gazeuse, doivent presenter des pores de rayon de l'ordre de 100 Angstrom et un debit aussi grand que possible. Elles doivent donc avoir une epaisseur faible et constante. Ces conditions necessitent une adaptation des methodes usuelles d'etude des corps poreux pour controler les caracteristiques des prototypes etudies. Il est apparu que seul le recoupement entre diverses methodes permet de suivre les progres dans la realisation de differents prototypes. L'expose qui va suivre comprend deux parties: 1) Une revue des principales methodes experimentales que nous utilisons: a) differentes methodes d'absorption, b) microscopie electronique, c) rayons X, d) porosimetrie a mercure, e) permeabilite aux liquides, f) permeabilite aux gaz, g) mesure de l'efficacite de separation. 2) Comparaison des differents resultats obtenus par ces diverses methodes et leur application

  16. Issues and challenges of the development of petroleum products distribution sector in Algeria; Les enjeux et les defis du developpement du secteur de la distribution des produits petroliers en Algerie

    Energy Technology Data Exchange (ETDEWEB)

    Akretche, Said

    2010-09-15

    The petroleum products distribution sector in Algeria is experiencing profound changes. The economic growth has brought an increase and a diversification of petroleum products consumption. Reforms on the opening of the sector to competition and regulations have allowed progress, especially in the promotion of clean products. Naftal invested in a transformation and modernization process to adapt to the new context and align itself with the worldwide best practices. This plan expects important investments for the promotion of clean products and the development of a ducting transport network to limit the environmental damage. [French] Le secteur de la distribution des produits petroliers en Algerie connait des mutations profondes. La croissance economique a induit une augmentation et une diversification de la consommation des produits petroliers. Les reformes portant ouverture du secteur a la concurrence et regulation ont permis des avancees notamment dans la promotion des produits propres. Naftal a engage un processus de transformation et modernisation pour s'adapter au nouveau contexte et s'aligner sur les meilleures pratiques mondiales. Ce plan prevoit d'importants investissements pour la promotion des produits propres et la realisation d'un reseau de transport par canalisation pour limiter les atteintes environnementales.

  17. The engineer, sustainable development craftsman at the center of the global energy challenge!; L'ingenieur, artisan du developpement durable au centre du defi energetique mondial!

    Energy Technology Data Exchange (ETDEWEB)

    Laplatte, Benjamin; Bourque, Francis; Granger, Francois P.; Dery, Gaston; Berube, Martin

    2010-09-15

    By its omnipresence in society, the energy question is at the heart of sustainable development issues. The engineer, as a central actor of human society development, is therefore tightly linked to the energy issue and he must actively contribute to resolve it by integrating to his practices the principles of sustainable development and by applying the solutions that arises. Part of these elements include as the main ones, listening to the consideration of citizens, becoming aware of the environment importance and reducing costs at all levels. The engineer is a social actor that cannot be ignored in the resolution of these issues. [French] Par son omnipresence dans la societe, la question energetique est au coeur des enjeux du developpement durable. L'ingenieur, etant un acteur central du developpement des societes humaines, est donc inextricablement lie a la question energetique qu'il doit contribuer activement a resoudre en integrant a sa pratique les principes du developpement durable et en appliquant les solutions qui en decoulent. Parmi ces elements, l'ecoute des considerations citoyennes, la prise de conscience de l'importance de l'environnement et la reduction des couts a tous les niveaux sont des elements centraux. L'ingenieur est un acteur social incontournable pour la resolution de ces enjeux.

  18. Development of uranium mining in France and the French Union; Developpement de l'industrie miniere de l'uranium en France et dans l'Union francaise

    Energy Technology Data Exchange (ETDEWEB)

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

    1958-07-01

    The decision taken by the French government as early as 1946 to pursue an extensive atomic energy development program laid immediate stress on the importance of finding adequate raw materials sources. The effort expended in this direction, as it is known through various publications on the subject, has culminated in very definite success: by the end of the present mining program, that is to say in 1961, France will occupy a significant position amongst world producers of uranium, and will be entirely independent in satisfying her requirements in uranium and thorium. Most of the uranium is mined within her own frontiers, which places the country in a very fortunate position. The types of deposits discovered and the methods of working them will be discussed in further reports. The present report looks back briefly over the discoveries themselves and outlines the situation to data, with an indication of the future development planned for these resources, completely unknown and unsuspected until a few years ago. (author) [French] La volonte de l'Etat fran is affirmee des 1946, de developper un programme notable d'energie atomique mit des cette epoque l'accent sur le probleme de l'approvisionnement en matieres premieres. Des efforts durent donc etre entrepris et l'on sait par diverses publications que ceux-ci ont obtenu un indeniable succes puisque la France se classera a l'achevement de ses proiets miniers actuels, c'est-a-dire vers 1961, a un rang honorable parmi les grands producteurs mondiaux et pourra ainsi s'approvisionner en uranium, et dans la mesure de ses besoins en thorium, sur ses propres mines, sans avoir a recourir a l'importation etrangere. On sait que la majeure partie de cet uranium provient du territoire metropolitain de la France, ce qui incontestablement est une grande chance pour elle. D'autres communications decriront les types de gisement et le detail des methodes employees. Il est propose ici, apres un bref historique sur les decouvertes, de

  19. Radiosensitivity of Sitophilus Zeamais Mots (S. Oryzae L.) at Various Stages of Development: A Study of the Larval Stages by Means of Radiography and 'Actographic' Recording; Sensibilite des Divers Stades de Developpement de Sitophilus Zeamais Mots (S. Oryzae L.) aux Radiations Ionisantes Etude des Stades Endoges par Radiographie et Enregistrement Actographique

    Energy Technology Data Exchange (ETDEWEB)

    Pesson, P.; Girish, G. K. [Institut National Agronomique, Paris (France)

    1968-06-15

    The paper describes an original method of study, based on the employment of an 'actograph' which records the vitality of the larval stages and makes it possible to study the larva population inside grains (actograph for electro-acoustic detection developed by the INRA Acoustic Physiology Laboratory, Jouy-en-Josas). The contamination rate and the death rate of the larvae are observed by radiography. The effects of irradiation at doses of 2000, 4000, 8000 and 16000 rad are studied in the egg stage, on larvae aged 5-7 days, 13-15 days and 19-21 days and on adults, whose fertility is measured 0-5 days, 5-10 days and 10-15 days after irradiation. The effects of irradiation on the second generation bred from the various stages irradiated are noted. (author) [French] Les auteurs presentent une methode d'etude originale, fondee sur l'emploi d'un appareillage actographique, qui enregistre et traduit la vitalite des stades endoges et permet d'apprecier la population larvaire a l'interieur des grains (actogtaphe a detection electro-acoustique mis au point par le Laboratoire de physiologie acoustique de l'INRA, Jouy-en-Josas). Le controle du taux de contamination et de la mortalite larvaire se fait par radiographie. Les auteursont etudie les effets de l'irradiation (doses de 2000, 4000, 8000 et 16 000 rad)sur le stade oeuf, sur les larves agees respectivement de 5 a 7 jours, 13 a 15 jours, 19 a 21 jours et sur les adultes (fecondite 0 a 5 jours, 5 a 10 jours, 10 a 15 jours apres l'irradiation); ils ont egalement fait des observations sur les consequences de l'irradiation sur la seconde generation issue des divers stades irradies. (author)

  20. Development of interface tracking method. Two-phase flows applications; Developpement d'une methode de suivi d'interface. Applications aux ecoulements diphasiques

    Energy Technology Data Exchange (ETDEWEB)

    Tanguy, S.

    2004-11-15

    Spray formation mechanisms study from a liquid-gas flow is a fundamental research subject, which industrial applications are large, especially in combustion and propulsion field. Numerical simulation of such flows appear as an essential complement to experimental and theoretical studies, for comprehension and accurate prediction of such physical processes. In this study we developed an numerical interface tracking technique with a Navier-Stokes solver to study accurately the liquid-gas interface dynamics. We describe Level Set method which has been used to track interface motion, and numerical methods for solving Navier-Stokes equations. Different numerical schemes have been tested to improve the computation accuracy. Ghost Fluid Method enables a robust and accurate treatment of discontinuities across the liquid-gas interface. The codes developed (2D, 3D, parallelization MPI) are then used to study droplets collisions. Comparisons with experimental results show that simulations are realistic and predictive. Next, feasibility studies are done on more complex configurations. Droplets spray formation from primary atomization of a liquid jet seems to be especially a promising investigation field for such simulations. Finally, reactive interfaces propagation, as liquid vaporization and premixed combustion have also been studied using Ghost Fluid Method to impose specific jump conditions. (author)

  1. Decontamination of surfaces (1961); La decontamination des surfaces (1961)

    Energy Technology Data Exchange (ETDEWEB)

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

    1961-07-01

    The continued expansion of atomic Energy has led the S.C.R.G.R. to extend simultaneously the recovery of materials contaminated by use in radio-active media. The importance of this aspect of atomic Energy was not immediately obvious to those concerned but is now fully recognized due to the cost of the materials and installations, and also to the time required for the construction of special equipment for the C.E.A. Another very important reason is the dangers associated with the handling of contaminated material. The S.C.R.G.R. attacked this problem from the point of view of these dangers. It later became apparent to the users, once the decontamination methods had proved their worth, that the process presented advantages from the material and cost-saving point of view. (author) [French] Le developpement toujours croissant de l'Energie atomique a conduit le S.C.R.G.R. a developper parallelement la recuperation des materiels contamines par leur emploi en milieu radioactif. Cet aspect de l'Energie atomique n'est pas apparu des le debut aux utilisateurs mais s'est tres vite impose etant donne, d'une part, le cout des installations et du materiel, d'autre part le temps necessaire a la fabrication d'un materiel special aux travaux du C.E.A., enfin et surtout, les risques associes a la manipulation d'un materiel contamine. Les risques seuls ont ete pris comme point de depart a l'examen de ce probleme par le S.C.R.G.R. puis avec le temps, les methodes de decontamination ayant fait leur preuve, les utilisateurs ont alors apercu les aspects materiels et la rentabilite de la decontamination. (auteur)

  2. Impact de la preparation des anodes crues et des conditions de cuisson sur la fissuration dans des anodes denses

    Science.gov (United States)

    Amrani, Salah

    fabriquees industriellement. Cette technique a consiste a determiner le profil des differentes proprietes physiques. En effet, la methode basee sur la mesure de la distribution de la resistivite electrique sur la totalite de l'echantillon est la technique qui a ete utilisee pour localiser la fissuration et les macro-pores. La microscopie optique et l'analyse d'image ont, quant a elles, permis de caracteriser les zones fissurees tout en determinant la structure des echantillons analyses a l'echelle microscopique. D'autres tests ont ete menes, et ils ont consiste a etudier des echantillons cylindriques d'anodes de 50 mm de diametre et de 130 mm de longueur. Ces derniers ont ete cuits dans un four a UQAC a differents taux de chauffage dans le but de pouvoir determiner l'influence des parametres de cuisson sur la formation de la fissuration dans ce genre de carottes. La caracterisation des echantillons d'anodes cuites a ete faite a l'aide de la microscopie electronique a balayage et de l'ultrason. La derniere partie des travaux realises a l'UQAC contient une etude sur la caracterisation des anodes fabriquees au laboratoire sous differentes conditions d'operation. L'evolution de la qualite de ces anodes a ete faite par l'utilisation de plusieurs techniques. L'evolution de la temperature de refroidissement des anodes crues de laboratoire a ete mesuree; et un modele mathematique a ete developpe et valide avec les donnees experimentales. Cela a pour objectif d'estimer la vitesse de refroidissement ainsi que le stress thermique. Toutes les anodes fabriquees ont ete caracterisees avant la cuisson par la determination de certaines proprietes physiques (resistivite electrique, densite apparente, densite optique et pourcentage de defauts). La tomographie et la distribution de la resistivite electrique, qui sont des techniques non destructives, ont ete employees pour evaluer les defauts internes des anodes. Pendant la cuisson des anodes de laboratoire, l'evolution de la resistivite

  3. Implementation Cryptography Data Encryption Standard (DES) and Triple Data Encryption Standard (3DES) Method in Communication System Based Near Field Communication (NFC)

    Science.gov (United States)

    Ratnadewi; Pramono Adhie, Roy; Hutama, Yonatan; Saleh Ahmar, A.; Setiawan, M. I.

    2018-01-01

    Cryptography is a method used to create secure communication by manipulating sent messages during the communication occurred so only intended party that can know the content of that messages. Some of the most commonly used cryptography methods to protect sent messages, especially in the form of text, are DES and 3DES cryptography method. This research will explain the DES and 3DES cryptography method and its use for stored data security in smart cards that working in the NFC-based communication system. Several things that will be explained in this research is the ways of working of DES and 3DES cryptography method in doing the protection process of a data and software engineering through the creation of application using C++ programming language to realize and test the performance of DES and 3DES cryptography method in encrypted data writing process to smart cards and decrypted data reading process from smart cards. The execution time of the entering and the reading process data using a smart card DES cryptography method is faster than using 3DES cryptography.

  4. Structure and kinematics of bubble flow; Structure et cinematique des ecoulements diphasiques a bulles

    Energy Technology Data Exchange (ETDEWEB)

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

    1967-07-01

    This report deals with the components and use of resistivity probes in bubble flow. With a single probe, we have studied the longitudinal and radial structure of the flow. The very complicated evolution of the radial structure is shown by the measurement of the mean bubble flux at several points in the tube. A double probe associated with a device the principle of which is given in this report, permits the measure of the local velocity of bubbles. Unlike the mean bubble flux profile, the change in the velocity profile along the tube is not significant. We have achieved the synthesis of these two pieces of information, mean local bubble flux and local velocity, by computing the mean weighed velocity in the tube. This weighed velocity compares remarkably with the velocity computed from the volumetric gas flow rate and the mean void fraction. (author) [French] Ce rapport traite d'une etude methodologique des ecoulements diphasiques a bulles. Les fluides sont l'air et l'eau, ils circulent du bas vers le haut dans un tube vertical de 32 mm de diametre et 2 metres de long. Cette etude a pour but de permettre une description fine de l'ecoulement. Pour cela, il a ete necessaire de developper des appareillages nouveaux et de mettre au point les methodes d'analyses correspondantes. La valeur des mesures effectuees et des methodes utilisees apparait dans une comparaison concluante et conclusive entre des resultats de mesures globales et des resultats integres de mesures locales. (auteur)

  5. Some methods for the detection of fissionable matter; Quelques methodes de detection des corps fissiles

    Energy Technology Data Exchange (ETDEWEB)

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

    1967-03-01

    A number of equipments or processes allowing to detect uranium or plutonium in industrial plants, and in particular to measure solution concentrations, are studied here. Each method has its own field of applications and has its own performances, which we have tried to define by calculations and by experiments. The following topics have been treated: {gamma} absorptiometer with an Am source, detection test by neutron multiplication, apparatus for the measurement of the {alpha} activity of a solution, fissionable matter detection by {gamma} emission, fissionable matter detection by neutron emission. (author) [French] On examine ici plusieurs appareils ou procedes qui permettent de detecter l'uranium ou le plutonium dans les installations industrielles, et en particulier de mesurer les concentrations de solutions. Chacune des methodes a son domaine d'application et ses performances, qu'on a tente de definir par le calcul et par des experiences. Les sujets traites sont les suivants: absorptiometre {gamma} a source d'americium, essais de detection par multiplication neutronique, appareil de mesure de l'activite {alpha} d'une solution, detection des matieres fissiles par leur emission {gamma}, detection des matieres fissiles par leur emission neutronique. (auteur)

  6. Utilisation des methodes modernes et reversibles de contraception ...

    African Journals Online (AJOL)

    Cette étude descriptive et transversale de 6 ans, allant du 1er Janvier 1999 au 10 Mai 2005 à la clinique de gynécologie obstétrique de l\\'hôpital Donka du CHU de Conakry, a fait ressortir le niveau d\\'utilisation des méthodes modernes de contraception et a permis d\\'élaboré des recommandations pour l\\'amélioration de la ...

  7. Experimental methods of reactor physics; Methodes experimentales de physique des reacteurs a neutrons thermiques

    Energy Technology Data Exchange (ETDEWEB)

    Breton, D; Lafore, P [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1964-07-01

    This paper is a synthesis of various experimental methods in use with the reactors of the Commissariat a l'Energie Atomique. The main techniques used are mentioned and the difficulties encountered and the accuracy obtained are particularly dwelt upon. The application of these various methods to reactors in order to obtain specific results is also indicated. This paper consists of five parts. I - General methods. Macroscopic and microscopic flux distribution (anisotropy effect), power distribution, etc... II - Kinetic measurements a) pulsed neutron technique: apparatus and accuracy; application to {lambda}t and to anti reactivity measurements; application to graphite, light water and beryllium oxide. b) oscillation techniques: equipment and accuracy; application to the measurements of effective cross sections and resonance integrals. c) fluctuations: apparatus and technique of measurement. III - Poison methods. Description of methods for introducing and extracting the poison, difficulties encountered with light and heavy water, measurement of temperature coefficients and anti-reactivity. IV - Spectra measurements. Choice and development of foils, problems of measurement, application to spectral measurements for thermalization studies, application to dosimetry. V - Experimental shielding measurements. The technique and apparatus recently developed in this field are presented. (authors) [French] Cette communication fait une synthese des differentes methodes experimentales mises en oeuvre sur les reacteurs du CEA. Elle presente les principales techniques utilisees et insiste plus particulierement sur les difficultes rencontrees et la precision obtenue; elle indique egalement l'application de ces differentes methodes sur les reacteurs, en vue de l'obtention des resultats determines. Elle comporte cinq parties: I - METHODES GENERALES: Distribution de flux macroscopique et microscopique (effet d'anisotropie), distribution de puissance, etc... II - MESURES CINETIQUES: a

  8. Etude des phenomenes dynamiques ultrarapides et des caracteristiques impulsionnelles d'emission terahertz du supraconducteur YBCO

    Science.gov (United States)

    Savard, Stephane

    Les premieres etudes d'antennes a base de supraconducteurs a haute temperature critique emettant une impulsion electromagnetique dont le contenu en frequence se situe dans le domaine terahertz remontent a 1996. Une antenne supraconductrice est formee d'un micro-pont d'une couche mince supraconductrice sur lequel un courant continu est applique. Un faisceau laser dans le visible est focalise sur le micro-pont et place le supraconducteur dans un etat hors-equilibre ou des paires sont brisees. Grace a la relaxation des quasiparticules en surplus et eventuellement de la reformation des paires supraconductrices, nous pouvons etudier la nature de la supraconductivite. L'analyse de la cinetique temporelle du champ electromagnetique emis par une telle antenne terahertz supraconductrice s'est averee utile pour decrire qualitativement les caracteristiques de celle-ci en fonction des parametres d'operation tels que le courant applique, la temperature et la puissance d'excitation. La comprehension de l'etat hors-equilibre est la cle pour comprendre le fonctionnement des antennes terahertz supraconductrices a haute temperature critique. Dans le but de comprendre ultimement cet etat hors-equilibre, nous avions besoin d'une methode et d'un modele pour extraire de facon plus systematique les proprietes intrinseques du materiau qui compose l'antenne terahertz a partir des caracteristiques d'emission de celle-ci. Nous avons developpe une procedure pour calibrer le spectrometre dans le domaine temporel en utilisant des antennes terahertz de GaAs bombarde aux protons H+ comme emetteur et detecteur. Une fois le montage calibre, nous y avons insere une antenne emettrice dipolaire de YBa 2Cu3O7-delta . Un modele avec des fonctions exponentielles de montee et de descente du signal est utilise pour lisser le spectre du champ electromagnetique de l'antenne de YBa 2Cu3O7-delta, ce qui nous permet d'extraire les proprietes intrinseques de ce dernier. Pour confirmer la validite du modele

  9. Caracterisation environnementale des emissions atmospheriques d'une source fixe et creation d'un outil de gestion dynamique =

    Science.gov (United States)

    Fournier, Marie-Claude

    Une caracterisation des emissions atmospheriques provenant des sources fixes en operation, alimentees au gaz et a l'huile legere, a ete conduite aux installations visees des sites no.1 et no.2. La caracterisation et les calculs theoriques des emissions atmospheriques aux installations des sites no.1 et no.2 presentent des resultats qui sont en dessous des valeurs reglementaires pour des conditions d'operation normales en periode hivernale et par consequent, a de plus fortes demandes energetiques. Ainsi, pour une demande energetique plus basse, le taux de contaminants dans les emissions atmospheriques pourrait egalement etre en dessous des reglementations municipales et provinciales en vigueur. Dans la perspective d'une nouvelle reglementation provinciale, dont les termes sont discutes depuis 2005, il serait souhaitable que le proprietaire des infrastructures visees participe aux echanges avec le Ministere du Developpement Durable, de l'Environnement et des Parcs (MDDEP) du Quebec. En effet, meme si le principe de droit acquis permettrait d'eviter d'etre assujetti a la nouvelle reglementation, l'application de ce type de principe ne s'inscrit pas dans ceux d'un developpement durable. L'âge avance des installations etudiees implique la planification d'un entretien rigoureux afin d'assurer les conditions optimales de combustion en fonction du type de combustible. Des tests de combustion sur une base reguliere sont donc recommandes. Afin de supporter le processus de suivi et d'evaluation de la performance environnementale des sources fixes, un outil d'aide a la gestion de l'information environnementale a ete developpe. Dans ce contexte, la poursuite du developpement d'un outil d'aide a la gestion de l'information environnementale faciliterait non seulement le travail des personnes affectees aux inventaires annuels mais egalement le processus de communication entre les differents acteurs concernes tant intra- qu'inter-etablissement. Cet outil serait egalement un bon

  10. 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

  11. Development of speciation analysis for selenium in nutritional supplements by the determination of the seleno-methionine; Developpement de l'analyse de speciation du selenium dans des complements alimentaires par la determination de la selenomethionine

    Energy Technology Data Exchange (ETDEWEB)

    Sannac, S.; Labarraque, G.; Fisicaro, P. [Laboratoire National de Metrologie et d' Essai (LNE), 75 - Paris (France); Sannac, S.; Pannier, F.; Potin-Gautier, M. [Pau Univ. et des Pays de l' Adour, CNRS/UMR 5254, Lab. de Chimie Analytique, Bio-Inorganique et Environnement (IPREM), 64 (France)

    2009-07-01

    The development of a reference method in analytical chemistry is presented. Liquid chromatography with inductively coupled plasma mass spectrometry is employed to perform in speciation analysis. Applications are developed for the determination of seleno-methionine in nutritional supplements. The use of isotope dilution, a primary method, is required to enable measurement traceability. Method validation is ensured by the study of a certified reference material. (authors)

  12. Comparative assessment of supervision and decision-making procedures regarding sustainable development; Evaluation comparee de methodes de controle et de decision en matiere de developpement durable

    Energy Technology Data Exchange (ETDEWEB)

    Carlevaro, F.; Garbely, M.; Genoud, S.

    2002-07-01

    This final report for the Swiss Federal Office of Energy (SFOE) presents the results of a study made on the possibilities of establishing a system of indicators that allows the monitoring of sustainable development and its effects, as stipulated in the Agenda 21. The report presents the findings of the study on criteria and indicators for sustainability in the energy area. The challenge posed by the synthesis of information from a system of indicators is discussed and four general approaches are proposed, compared and tested for the monitoring of sustainability in the energy area. These include the calculation of a composite index from several indicators, a similar process that uses statistical methods of dimensional reduction, methods for the measurement of productivity loaned from economics and a method for decision-making using multiple criteria. Examples for the four approaches are given and experience gained in their use - partly in other countries and in United Nations agencies - is discussed.

  13. Interpretation of the distortion of ground-penetrating radar propagated and reflected waves - development of a multi-frequency tomography; Interpretation de la distorsion des signaux georadar propages et reflechis. Developpement d'une tomographie par bandes de frequence

    Energy Technology Data Exchange (ETDEWEB)

    Hollender, F

    1999-07-01

    Within the framework of research for waste disposal in deep geological formations, the French agency for nuclear waste management (ANDRA) has to dispose of non-destructive investigation methods to characterize the medium. Ground penetrating radar (GPR) could be used for this purpose in the case of granitic sites. The work presented here deals with this geophysical method. The classical interpretation of GPR data consists in the localization of geological discontinuities by signal amplitude or arrival time analysis. The main objective of our studies is the interpretation of the radar wave distortion (due to propagation and reflection phenomena), not only to localize discontinuities but also to contribute to their identification. Three preliminary studies have been carried out in order to understand on the one hand, the complexity of the electromagnetic phenomena in the geological medium at radar frequency, and on the other hand, the radar equipment constraints. First, the dispersion and the attenuation characterized by a Q variable factor of the GPR waves are shown with the support of dielectric laboratory measurements. A model, which only requires three parameters, is proposed in order to describe this behavior. Second, the radiation patterns of borehole radar antenna are studied. We show that the amplitude and frequency content of the emitted signal are variable versus the emission angle. An analytical method is proposed to study these phenomena. Finally, instrumental drifts of GPR equipment are studied. Emission time, sampling frequency and amplitude fluctuations are described. These elements are taken into account for the processing of propagated signals by tomographic inversion. Medium anisotropy and borehole trajectory errors are inserted in algorithms in order to cancel artifacts which compromised the previous interpretation. A pre-processing method, based on wave separation algorithm, is applied on data in order to increase tomogram resolution. A new

  14. Developpement of an original aerial-based inventory method: first steps towards the use of mini Unmanned Areal Vehicle in elephant inventory

    OpenAIRE

    Lisein, Jonathan; Vermeulen, Cédric; Bouché, Philippe; Lejeune, Philippe

    2012-01-01

    This research aims at developping a new methodology for counting large mammals by means of an unmanned aerial vehicle. Test flights have been performed in the game ranch of Nazinga (Burkina Faso) during the month of february 2012. Aerial images shows that elephant detection is quite feasible. The systems still requires a lot of improvements in order to be able to cover bigger surfaces for a given pixels resolution. Nevertheless, this method seems very promissing and could advantageously repla...

  15. Development of radioiodinated ligands for exploration of brain monoamine oxidase by tomo-scintigraphy; Developpement de ligands radioactifs pour l'exploration des monoamines oxydases cerebrales en tomoscintigraphie

    Energy Technology Data Exchange (ETDEWEB)

    Rafii, H

    1996-07-01

    Monoamine oxidases, MAO, are important in the regulation of monoaminergic neuro-transmissions. The fluctuations in MAO activities has been observed in some psychiatric and neuro-degenerative diseases. Thus, quantification of cerebral MAO activity would be useful for diagnosis and the therapeutic follow-up of these disorders. With the object of doing an in vivo scintigraphic exploration of cerebral MAO by SPECT, we have undertaken to synthesize some radioiodinated MAO inhibitors. In the first part of this work, we have discussed the general properties of the monoamine oxidases and their inhibitors. In the second part we have described the scintigraphic methods. the ligands to be used for MAO exploration, and the radioiodination methods. At last in the third part, the development of three radioiodinated ligands has been presented: - [{sup 125}I]3-iodopargyline. In vivo results showed that, this radioligand blocked the cerebral MAO-B with moderate selectivity. However, complementary in vivo studies would be needed to define precisely its activity.- [{sup 125}I]Ro 16-6491. The cerebral fixation of this radioligand was in accordance with the MAO-B sites in the rat brains, but its fixation was too low for scintigraphic exploration in vivo with iodine-123. - [{sup 125}I]Ro 11-9900. In vivo studies of rat brains showed that the MAO-A sites were bound preferentially by this radioligand. The cerebral biodistribution of this ligand labelled with iodine-123 is considered for use in a model animal nearest to human pathology. (author)

  16. 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)

  17. Application of mathematical methods to the investigation of uranium deposits; Application des methodes mathematiques a l'etude des gisements d'uranium

    Energy Technology Data Exchange (ETDEWEB)

    Formery, P; Ziegler, V [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1958-07-01

    It may be considered approximately that grades, widths and accumulations (grade-width products), in french uranium deposits are distributed according to a lognormal law. This property associated to KRIGE'S and de WIGE'S formulae make a powerful tool in ore deposits surveys. The correlation between radioactivities and grades is realized, in logarithmic coordinates, through a straight line the properties of which are analysed in the paper. MATHERON'S recent works, in association with data of classical statistics and the above mentioned formulae make possible to complete the ore reserves evaluation by computing the accuracy. Statistical methods applied to ore deposits have given birth to a parameter which is as important as the mean grade for characterisation of deposits: the absolute dispersion. (author) [French] On peut considerer en premiere approximation que les teneurs, les puissances et les accumulations se distribuent dans les gisements fran is d'uranium suivant une loi log normale. Cette propriete, associee aux hypotheses de De WIGE et de KRIGE, constitue un puissant instrument d'etude des gisements. La correspondance des radioactivites et des teneurs s'effectue, en coordonnees bilogarithmiques, par une droite dont on etudie les proprietes. Grace aux travaux recents de MATHERON, associes aux donnees de la statistique classique ainsi qu'aux hypotheses enumerees plus haut, il est possible de completer le calcul des reserves d'un gisement par une evaluation de l'erreur commise. Les methodes statistiques ont fait apparaitre un parametre aussi important pour caracteriser un gisement, que la teneur moyenne: la dispersion absolue. (auteur)

  18. Development, improvement and calibration of neutronic reaction rate measurements: elaboration of a base of standard techniques; Developpement, amelioration et calibration des mesures de taux de reaction neutroniques: elaboration d`une base de techniques standards

    Energy Technology Data Exchange (ETDEWEB)

    Hudelot, J.P

    1998-06-19

    In order to improve and to validate the neutronic calculation schemes, perfecting integral measurements of neutronic parameters is necessary. This thesis focuses on the conception, the improvement and the development of neutronic reaction rates measurements, and aims at building a base of standard techniques. Two subjects are discussed. The first one deals with direct measurements by fission chambers. A short presentation of the different usual techniques is given. Then, those last ones are applied through the example of doubling time measurements on the EOLE facility during the MISTRAL 1 experimental programme. Two calibration devices of fission chambers are developed: a thermal column located in the central part of the MINERVE facility, and a calibration cell using a pulsed high flux neutron generator and based on the discrimination of the energy of the neutrons with a time-of-flight method. This second device will soon allow to measure the mass of fission chambers with a precision of about 1 %. Finally, the necessity of those calibrations will be shown through spectral indices measurements in core MISTRAL 1 (UO{sub 2}) and MISTRAL 2 (MOX) of the EOLE facility. In each case, the associated calculation schemes, performed using the Monte Carlo MCNP code with the ENDF-BV library, will be validated. Concerning the second one, the goal is to develop a method for measuring the modified conversion ratio of {sup 238}U (defined as the ratio of {sup 238}U capture rate to total fission rate) by gamma-ray spectrometry of fuel rods. Within the framework of the MISTRAL 1 and MISTRAL 2 programmes, the measurement device, the experimental results and the spectrometer calibration are described. Furthermore, the MCNP calculations of neutron self-shielding and gamma self-absorption are validated. It is finally shown that measurement uncertainties are better than 1 %. The extension of this technique to future modified conversion ratio measurements for {sup 242}Pu (on MOX rods) and

  19. Study and management of atmospheric exhaust gas in acetic acid fermentation developing a new process for alcohol vinegar production; Etude et maitrise des rejets atmospheriques en vinaigrerie, developpement d'un procede nouveau de conduite de la fermentation acetique

    Energy Technology Data Exchange (ETDEWEB)

    Pochat Bohatier, C

    1999-12-06

    The aim of the study was to examine emissions of volatile organic compounds (VOCs) during acetic (acid) fermentation. The first part of the study presents the methodology developed to reproduce production cycles for spirit vinegar and to analyse gas effluents. The second part describes the origin and quantification of the emissions (ethanol, acetic acid, acetaldehyde and ethyl acetate). The acetic acid is produced by bacterial metabolism while the ethyl acetate is a result of the chemical reaction of esterification. By modelling the emissions during batch processing we were able to identify the various parameters involved when VOCs are carried along by the fermentation gases. The quantities of ethyl acetate depend on the length of time the diluted alcohol is stored, and on its composition. By using a fed-batch method with a continuous supply of ethanol we could reduce alcohol emissions. The third part of the study develops the kinetics studies carried out to adapt the fed-batch process to acetic acid fermentation. The influence of ethanol, either in terms of deficiency or inhibition, is minimized between 8 and 16 g.1-1. A study of the growth rate of bacteria in relation to the amount of acetic acid showed that the latter was highly inhibitive. There is a critical concentration of acetic acid at which the growth of bacteria stops, and the death rate of the culture increases rapidly. The latter depends on the composition of the culture's medium; the corresponding pH of the concentration is between 2.25 and 2.28. By limiting the formation of ethyl acetate in the diluted alcohol and by controlling the concentration of ethanol at 16 g.l -1 per fermentation, the VOC emissions are reduced by 30% and the yield increases as a result. (author)

  20. Enrollment of a population-based cohort of newborns at higher risk of developing a chronic condition: the EDEN study. Etude du Developpement des Nouveau-nés Study.

    Science.gov (United States)

    Addor, V; Santos-Eggimann, B; Fawer, C L; Paccaud, F; Calame, A

    1997-04-01

    To describe the methods used at birth to recruit a population-based cohort of newborns of all birthweights at higher risk of having a chronic condition, and to present baseline results. Screening of all newborns at hospital discharge for five non-exclusive criteria: (1) low birthweight (LBW), (2) congenital anomalies or genetic disease, (3) specified conditions associated with a high probability of chronicity, (4) referral to a neonatal intensive care unit (NICU), (5) or defined social problems. Calculation of Hobel risk scores for children satisfying > or = 1 criterion. All 6477 live births delivered in the 19 maternity hospitals of a geographically defined region (Vaud, Switzerland) to resident mothers in 1993-1994. Twelve per cent (n = 760) of newborns met > or = 1 criterion: 6.3% of all newborns had an LBW (criterion 1), 2.4% had a birth defect, 0.9% met criterion (3), 4.4% stayed in an NICU and 1.6% had serious social problems. Hobel prenatal score was high (> or = 10 points) for 41% of children with > or = 1 criterion, the intrapartum score for 87% and the neonatal score for 68%. Most newborns identified by the above simple criteria also had elevated perinatal risks. The validity of the criteria will later be tested against the results of the examinations of children with > or = 1 criterion at 18 months and 4 years of age, but the assessment at birth already shows that normal birthweight (NBW) children, in agreement with previous studies, contribute half the children at high risk perinatally.

  1. Study and management of atmospheric exhaust gas in acetic acid fermentation developing a new process for alcohol vinegar production; Etude et maitrise des rejets atmospheriques en vinaigrerie, developpement d'un procede nouveau de conduite de la fermentation acetique

    Energy Technology Data Exchange (ETDEWEB)

    Pochat Bohatier, C.

    1999-12-06

    The aim of the study was to examine emissions of volatile organic compounds (VOCs) during acetic (acid) fermentation. The first part of the study presents the methodology developed to reproduce production cycles for spirit vinegar and to analyse gas effluents. The second part describes the origin and quantification of the emissions (ethanol, acetic acid, acetaldehyde and ethyl acetate). The acetic acid is produced by bacterial metabolism while the ethyl acetate is a result of the chemical reaction of esterification. By modelling the emissions during batch processing we were able to identify the various parameters involved when VOCs are carried along by the fermentation gases. The quantities of ethyl acetate depend on the length of time the diluted alcohol is stored, and on its composition. By using a fed-batch method with a continuous supply of ethanol we could reduce alcohol emissions. The third part of the study develops the kinetics studies carried out to adapt the fed-batch process to acetic acid fermentation. The influence of ethanol, either in terms of deficiency or inhibition, is minimized between 8 and 16 g.1-1. A study of the growth rate of bacteria in relation to the amount of acetic acid showed that the latter was highly inhibitive. There is a critical concentration of acetic acid at which the growth of bacteria stops, and the death rate of the culture increases rapidly. The latter depends on the composition of the culture's medium; the corresponding pH of the concentration is between 2.25 and 2.28. By limiting the formation of ethyl acetate in the diluted alcohol and by controlling the concentration of ethanol at 16 g.l -1 per fermentation, the VOC emissions are reduced by 30% and the yield increases as a result. (author)

  2. Method of research and study of uranium deposits; Methode de recherches et d'etude des gites uraniferes

    Energy Technology Data Exchange (ETDEWEB)

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

    1955-07-01

    In a first part, the author gives a fast retrospective of the evaluations of the uranium deposits in the French Union. The author established a method of prospecting and studying, modifiable at all times following the experiences and the results, permitting to make the general inventory of uranium resources on the territory. The method is based on: 1 - the determination of geological guides in order to mark the most promising deposits, 2 - the definition of a methodology adapted to every steps of the research, 3 - the choice of the material adapted for each of the steps. This method, originally established for the prospecting in crystalline massifs, is adaptable to the prospecting of the sedimentary formations. (M.B.) [French] Dans une premiere partie, l'auteur donne une retrospective rapide des estimations des gites uraniferes dans l'Union Francaise. L'auteur a etabli une methode de prospection et d'etude, modifiable a tout instant suivant les experiences et les resultats, permettant de faire l'inventaire general des ressources en uranium du territoire. La methode est base sur: 1 - la determination de guides geologiques afin de reperer les gisements les plus prometteurs, 2 - la definition d'une methodologie adaptee a chaque stade de la recherche, 3 - le choix du materiel adapte pour chacun des stades. Cette methode, a l'origine etablie pour la prospection en massifs cristallins, est adaptable a la prospection des formations sedimentaires. (M.B.)

  3. developpement des systemes de production innovants d'association ...

    African Journals Online (AJOL)

    Dans ce contexte de crises récurrentes, le projet. « Conception de systèmes de production innovants à base de Mucuna et autres cultures fourragères » a été exécuté en zone subhumide du Mali et du Burkina Faso dans le cadre du. Projet d'Appui à l'Enseignement Supérieur. (PAES) dans les pays de l'Union Economique.

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

    African Journals Online (AJOL)

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

  5. Developing countries` energy requirements; Besoins energetiques des pays en developpement

    Energy Technology Data Exchange (ETDEWEB)

    Arques, P. [Ecole Centrale Lyonnaise, 69 - Ecully (France)

    1995-03-01

    The amount of electric power and bacteriologically clean water produced in developing countries today is insufficient for the people`s needs. In order to develop successfully, these countries must necessarily achieve a threshold which, for the whole planet, will come to 1 000 000 MW of electricity. One way this can be done is by building several hundred power plants, with all the concomitant pollution problems. Another solution is Stirling motors, which use the power of sunlight to pump and pasteurize water and to generate electricity for one or more families, or for developmental home industries. (author). 4 refs., 6 figs.

  6. DEVELOPPEMENT DES COMPRIMES AVEC ACIDE ACETYLSALICILIQUE TAMPONNEES (AAST

    Directory of Open Access Journals (Sweden)

    Radu G. Cazacincu

    2010-10-01

    Full Text Available On the Romanian market there are several buffered acetylsalycilic acid tablets (BASAT, made by different producers that use the same acetylsalycilic acid quantity (500 mg/tablet but use different agents like calcium gluconate (150 mg/tablet or calcium carbonate (250 mg/tablet. The objective of this work is to obtain an optimal formulation for BASAT. Four different BASAT formulations have been obtained by wet granulation followed by compression. These formulations have been submitted to control tests as indicated by Pharmacopoeias. All the four formulations correspond regarding organoleptic examination, mass uniformity, mechanical strength (mean values between 67.6 – 199.4 N, friability (0.1832 – 0.4612% compared to max. 1%, disintegration (33.6 – 76.66 s. The mechanical strength and disintegration for F3 are greater than for F1, F2, and F4. The neutralizing capacity (0.91 – 2.71 mEq HCl that can neutralize 325 mg acetylsalycilic acid is according to Pharmacopoeia only for F3 and F4 formulations.

  7. Calculation of pole profiles for the design of particle accelerators magnets. Equivalent current and conformal representation methods; Calcul de profils polaires destines a des aimants d'accelerateurs de particules. Methode des courants et methode des transformations conformes

    Energy Technology Data Exchange (ETDEWEB)

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

    1968-04-01

    These two methods allow the determination of the shape of the poles in magnets, for a given field distribution in the air-gap. First method: The principle of the method consists to create the desired law of field by means of current sheets in which one can adjust the density given in a polynomial form. For the right distribution of these currents, the equipotential corresponding to the magnetic potential of the excitation coils is calculated. The pole profile of the H or C magnet identified with this equipotential line will finally take the place of the distribution of the current sheets used in the calculation. Steel permeability is assumed to be infinite and Foucault current effects are neglected in the case of variable fields. Second method: It consists to find a conformal representation that maps the pole profile plane upon the upper half of another plane where the equipotentials are two half straight lines, and where the field problems are easier to solve. Steel permeability is also considered to be infinite and the coils far from the pole faces. This known method has been applied to be compared with the first one. (author) [French] Ces deux methodes consistent a determiner la forme des pieces polaires d'aimants pour une distribution de champ determinee a l'avance dans l'entrefer. Premiere methode: Le principe de la methode consiste a creer la loi de champ desiree par l'intermediaire de nappes de courant dont on peut ajuster la densite exprimee sous une forme polynominale. Pour une distribution convenable de ces courants, on calcule l'equipotentielle correspondant au potentiel magnetique des bobines d'excitation. Le profil polaire d'un aimant en H ou C identifie a l'equipotentielle se substitue finalement a la repartition des nappes de courant utilisee dans la methode de calcul. La permeabilite de l'acier est supposee infinie et les courants de Foucault sont negliges dans le cas des champs variables. Seconde methode: Elle consiste a trouver une transformation

  8. Recent Developments in the Theory of Mechanisms in Radiation Chemical Processes; Developpements recents dans la theorie des mecanismes des reactions radiochimiques; Poslednie dostizheniya v teorii mekhanizmov radiatsionno-khimicheski kh protsessov; Adelantos recientes en la interpretacion teorica del mecanismo de los procesos radioquimicos

    Energy Technology Data Exchange (ETDEWEB)

    Roberts, R. [U.K.A.E.A., Wantage Research Laboratory, Berks (United Kingdom)

    1963-11-15

    Recent developments in the mechanisms of radiation-initiated chemical reactions are reviewed. The role of ion molecule processes is reviewed, with particular reference to the radiation chemistry of methane. In this system, the existence of reactions of excited molecules, in addition to ionic processes is deduced. It is shown that, in the radiolysis of methane, unsaturated hydrocarbons play a considerable part in the mechanism of reaction. Developments in ionic polymerization and also polymerization under heterogenous conditions are reviewed. The importance of reactant purity, and also cleanliness of reaction vessels is discussed. The effect of an applied external potential in solid state polymerization is briefly reviewed. The importance of free-radical processes to radiation chemists is considered in the light of the Dow process for the production of ethyl bromide. (author) [French] L'auteur examine les resultats recents obtenus dans l'etude des mecanismes des reactions chimiques radio-induites. Il etudie l'importance des reactions ion-molecule, en considerant tout particulierement la radio-chimie due methane. Il en deduit qu'il existe dans ce systeme, outre les phenomenes ioniques, des reactions de molecules excitees. il montre que les hydrocarbures non satures jouent un role considerable dans la radiolyse du methane. Il passe en revue les resultats obtenus dans la polymerisation ionique ainsi que dans la polymerisation dans des conditions heterogenes. Il insiste sur l'importance de la purete des reactifs ainsi que sur la proprete des recipients. En meme temps, il examine brievement l'effet d'un potentiel exterieur sur la polymerisation a l'etat solide. Il signale l'importance radiochimique des reactions fondees sur des radicaux liebre, libres sous l'angle du procede Dow pour la production de bromure d'ethyle. (author) [Spanish] El autor examina los recientes progresos realizados en el estudio de los mecanismos de las reacciones quimicas radioinducidas. Sedala la

  9. Comparison between ARIMA and DES Methods of Forecasting Population for Housing Demand in Johor

    OpenAIRE

    Alias Ahmad Rizal; Zainun Noor Yasmin; Abdul Rahman Ismail

    2016-01-01

    Forecasting accuracy is a primary criterion in selecting appropriate method of prediction. Even though there are various methods of forecasting however not all of these methods are able to predict with good accuracy. This paper presents an evaluation of two methods of population forecasting for housing demand. These methods are Autoregressive Integrated Moving Average (ARIMA) and Double Exponential Smoothing (DES). Both of the methods are principally adopting univariate time series analysis w...

  10. Development of an experimental device based on the digitalization of the signal and dedicated to the characterization of fission fragments and prompt neutrons; Developpement d'un dispositif experimental base sur la digitalisation des signaux et dedie a la caracterisation des fragments de fission et des neutrons prompts emis

    Energy Technology Data Exchange (ETDEWEB)

    Varapai, N

    2006-12-15

    The present work demonstrates the application of the digital technique for nuclear measurements. This new technique is based on the digitalization of the signals from the detectors and has several advantages. This technique allows us to extract the maximum amount of information contained in the signal shape. In the case of an ionization chamber this signal contains the necessary information on the particle kinetic energy, emission angle and mass. This method has been implemented for measurements of promptly emitted fission neutrons in coincidence with fission fragments from {sup 252}Cf(sf). A double Frisch-grid ionization chamber is used as fission fragment detector. The promptly emitted neutrons are detected by a NE213 liquid scintillation detector. This work displays how delicate analysis of the digitalized signals permitted us to infer the mass and kinetic energy distributions of the fission fragments as well as the neutron energy spectrum and multiplicity. The outline of this thesis is as follows: Chapter 2 gives an overview of the experimental tools used in this work. Chapter 3 explains the analysis procedure of the digitalized anode signal from an ionization chamber. Chapter 4 gives a detailed explanation of the analysis procedure of the digitalized signal from a neutron detector. In Chapter 5 the analysis procedure of the fission fragment events in coincidence with neutrons is given.

  11. Methodes d'amas quantiques a temperature finie appliquees au modele de Hubbard

    Science.gov (United States)

    Plouffe, Dany

    Depuis leur decouverte dans les annees 80, les supraconducteurs a haute temperature critique ont suscite beaucoup d'interet en physique du solide. Comprendre l'origine des phases observees dans ces materiaux, telle la supraconductivite, est l'un des grands defis de la physique theorique du solide des 25 dernieres annees. L'un des mecanismes pressentis pour expliquer ces phenomenes est la forte interaction electron-electron. Le modele de Hubbard est l'un des modeles les plus simples pour tenir compte de ces interactions. Malgre la simplicite apparente de ce modele, certaines de ses caracteristiques, dont son diagramme de phase, ne sont toujours pas bien etablies, et ce malgre plusieurs avancements theoriques dans les dernieres annees. Cette etude se consacre a faire une analyse de methodes numeriques permettant de calculer diverses proprietes du modele de Hubbard en fonction de la temperature. Nous decrivons des methodes (la VCA et la CPT) qui permettent de calculer approximativement la fonction de Green a temperature finie sur un systeme infini a partir de la fonction de Green calculee sur un amas de taille finie. Pour calculer ces fonctions de Green, nous allons utiliser des methodes permettant de reduire considerablement les efforts numeriques necessaires pour les calculs des moyennes thermodynamiques, en reduisant considerablement l'espace des etats a considerer dans ces moyennes. Bien que cette etude vise d'abord a developper des methodes d'amas pour resoudre le modele de Hubbard a temperature finie de facon generale ainsi qu'a etudier les proprietes de base de ce modele, nous allons l'appliquer a des conditions qui s'approchent de supraconducteurs a haute temperature critique. Les methodes presentees dans cette etude permettent de tracer un diagramme de phase pour l'antiferromagnetisme et la supraconductivite qui presentent plusieurs similarites avec celui des supraconducteurs a haute temperature. Mots-cles : modele de Hubbard, thermodynamique

  12. Sur la dynamique et la commande des colonnes multicomposées

    OpenAIRE

    Creff , Yann

    1992-01-01

    ON S'INTERESSE A LA COMMANDE EN QUALITE DE COLONNES A DISTILLER MULTICOMPOSEES, EN ETENDANT AUX COLONNES PSEUDO-BINAIRES DES RESULTATS RECENTS ETABLIS POUR LES COLONNES BINAIRES. ON COMMENCE PAR METTRE EN EVIDENCE LA DIFFICULTE D'ETENDRE DIRECTEMENT LES TECHNIQUES EMPLOYEES DANS LE CAS BINAIRE. ON DEMONTRE DANS CE CADRE UNE PROPRIETE VERIFIEE PAR LE JACOBIEN DES FONCTIONS D'EQUILIBRE LIQUIDE-VAPEUR ET ON AFFINE LA DESCRIPTION GEOMETRIQUE DE LA DYNAMIQUE DU FLASH. ON DEVELOPPE ENSUITE UNE TECH...

  13. Study of the long-term values and prices of plutonium; a simplified parametrized model; Etude des valeurs et des prix du plutonium a long terme; un modele parametre simplifie

    Energy Technology Data Exchange (ETDEWEB)

    Gaussens, J; Paillot, H [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1965-07-01

    The authors define the notions of use values and price of plutonium. They give a 'simplified parametrized model' simulating the equilibrium of the offer and the demand in time, concerning the plutonium and the price deriving from the relative scarcity of this metal, taking into account the technical and economic operating parameters of the various reactors confronted. This model is simple enough to allow direct computations and establish clear relations between the various parameters. The use of the linear programmes method allows on the other hand a wide extension of the model. This report includes three main parts: I - General description of the study (without detailed calculations) II - Mathematical development of the simplified parametrized model and application (the basic data and the results of the calculations are given) III - Appendices (giving the detailed computations of part II). (authors) [French] Les auteurs definissent les notions de valeurs d'usage et de prix du plutonium. Ils donnent un 'modele parametre simplifie' simulant l'equilibre de l'office et de la demande dans le temps concernant le plutonium et le prix qui decoule de la rarete relative de ce metal, compte tenu des parametres techniques et economiques de fonctionnement des divers reacteurs en presence. Ce modele est suffisamment simple pour permettre des calculs manuels et etablir des liaisons claires entre les divers parametres. L'utilisation de la technique des programmes lineaires permet par ailleurs une extension considerable du modele. Cette note comprend trois parties: I - Expose general de l'etude (sans expose du detail des calculs) II - Developpement mathematique du modele parametre simplifie et application (on precise les donnees de base et le resultat des calculs) III - Annexes (donnant le detail des calculs de la partie II). (auteurs)

  14. New method for studying the efficiency of chelating agents of the polyamine acid series for internal decontamination; Methode nouvelle d'etude de l'efficacite des chelateurs de la serie des acides polyamines pour la decontamination interne

    Energy Technology Data Exchange (ETDEWEB)

    Lafuma, J; Nenot, J C; Morin, M [Commissariat a l' Energie Atomique, Fontenay-aux-Roses (France). Centre d' Etudes Nucleaires

    1968-07-01

    We followed the biological fate of a complex formed on one side with either a rare earth (cerium-144) or a transuranium element (plutonium-239), and on the other side with a chelating agent of the polyamino acid series (EDTA, BAETA, DTPA, TTHA). This method allowed to study: 1 - the in vivo stability of the various complexes and to compare them; 2 - the stability of the complexes as a function of the isotope - chelating agent weight relationships; 3 - the metabolism of the chelating agents resulting in stable complexes, i. e. DTPA and TTHA mainly. This simple method brought out the higher efficiency, of DTPA in chelating rare earths and plutonium and for therapeutic purposes. (authors) [French] La methode consiste a suivre le devenir biologique d'un complexe forme d'une part avec une terre rare (cerium 144) ou un transuranien (plutonium 239) et d'autre part avec un chelateur de la serie des acides polyamines (EDTA, BAETA, DTPA, TTHA). Elle permet d'etudier: 1 - la stabilite in vivo des differents complexes, de les comparer; 2 - la stabilite des complexes en fonction des rapports ponderaux isotope - chelateurs; 3 - le metabolisme des chelateurs formant des complexes stables, essentiellement DTPA et TTHA. Cette methode simple degage la suprematie du DTPA en ce qui concerne la chelation des terres rares et du plutonium, et son utilisation a des fins therapeutiques. (auteurs)

  15. New method for studying the efficiency of chelating agents of the polyamine acid series for internal decontamination; Methode nouvelle d'etude de l'efficacite des chelateurs de la serie des acides polyamines pour la decontamination interne

    Energy Technology Data Exchange (ETDEWEB)

    Lafuma, J.; Nenot, J.C.; Morin, M. [Commissariat a l' Energie Atomique, Fontenay-aux-Roses (France). Centre d' Etudes Nucleaires

    1968-07-01

    We followed the biological fate of a complex formed on one side with either a rare earth (cerium-144) or a transuranium element (plutonium-239), and on the other side with a chelating agent of the polyamino acid series (EDTA, BAETA, DTPA, TTHA). This method allowed to study: 1 - the in vivo stability of the various complexes and to compare them; 2 - the stability of the complexes as a function of the isotope - chelating agent weight relationships; 3 - the metabolism of the chelating agents resulting in stable complexes, i. e. DTPA and TTHA mainly. This simple method brought out the higher efficiency, of DTPA in chelating rare earths and plutonium and for therapeutic purposes. (authors) [French] La methode consiste a suivre le devenir biologique d'un complexe forme d'une part avec une terre rare (cerium 144) ou un transuranien (plutonium 239) et d'autre part avec un chelateur de la serie des acides polyamines (EDTA, BAETA, DTPA, TTHA). Elle permet d'etudier: 1 - la stabilite in vivo des differents complexes, de les comparer; 2 - la stabilite des complexes en fonction des rapports ponderaux isotope - chelateurs; 3 - le metabolisme des chelateurs formant des complexes stables, essentiellement DTPA et TTHA. Cette methode simple degage la suprematie du DTPA en ce qui concerne la chelation des terres rares et du plutonium, et son utilisation a des fins therapeutiques. (auteurs)

  16. The study of neutron transport by oscillation method; Etude du transport des neutrons par la methode de modulation

    Energy Technology Data Exchange (ETDEWEB)

    Raievski, V

    1959-07-01

    The oscillation method is of very general use for studying the behavior of thermal neutrons in media. The main experiments are described and a general theory of them is given. This theory, which is presented in the first part, is established using the two-group approximation which has proved its efficiency in the case of thermal neutron piles. The validity of the two-group approximation is recalled. This allows definition of the meaning of the parameters used in the theory and which are measured in these experiments. The experiments carried out by this method are described, especially those performed at the Centre d'Etudes Nucleaires de Saclay where the method has been extensively used. These experiments are interpreted by means of the general theory given previously. In this way, the identity of parameters measured by this method and those given by the theory is proved. This is particularly conclusive is the case of the mean life of neutrons in a pile. (author) [French] La methode de modulation est un procede tres general d'etude des proprietes neutroniques des milieux contenant des neutrons thermiques. Le present rapport a pour but de decrire les principales de ces experiences et d'en donner une theorie generale. Cette theorie, exposee dans la premiere partie, est etablie dons le cadre de l'approximation a deux groupes de vitesse qui a prouve son efficacite dons le cas des piles a neutrons thermiques. Le domaine de validite de l'approximation a deux groupes est rappele au debut, ce qui permet de definir avec precision la signification des parametres qui entrent dons la theorie et qui font l'objet de ces mesures. La deuxieme partie decrit les experiences realisees, en particulier celles effectuees au Centre d'Etudes Nucleaires de Saclay ou la methode a ete considerablement developpee. Ces experiences sont interpretees dans le cadre de la theorie generale exposee precedemment. On prouve ainsi l'identite des parametres mesures par cette methode et de ceux figurant

  17. The Non-Destructive Testing of Fuel Elements and Their Components for the United Kingdom Power-Reactor Development Programme; Controle Non Destructif des Elements Combustibles et de Leurs Parties Constitutives dans le Cadre du Programme de Developpement des Reacteurs de Puissance au Royaume-Uni; Nedestruktivnoe ispytanie teplovydelyayushchikh ehlementov i ikh komponentov dlya osushchestvleniya programmy soedinennogo korolevstva po razrabotke ehnergeticheskikh reaktorov; Ensayo No Destructivo de Elementos Combustibles y sus Componentes, en el Marco del Programa de Reactores de Potencia del Reino Unido

    Energy Technology Data Exchange (ETDEWEB)

    Mann, C. A.; Campsie, I. C. [U.K.A.E.A., Reactor Fuel Element Laboratories, Springfields, Salwick, Preston, Lancs. (United Kingdom)

    1965-10-15

    and the ends closed. In addition, the integrity of end closures is established, by radiography. Multiple exposures are commonly made to examine the whole of circumferential weld adequately. The disposition of the fuel can also be recorded accurately by using a panoramic technique. The use of colour radiography is also discussed. Pins are normally tested for leakage after filling with helium, using a mass-spectrometer leak detector. Pins not filled with helium may be tested using a ''back-pressurizing'' technique. Conventional ''probing'' and ''sniffing'' methods are used when it is desirable to locate the sites of leaks. The bubble test in liquids is also used, as a cheap and simple test. The use of krypton-85 as a tracer gas is discussed. (author) [French] Les auteurs decrivent les methodes d'essai que les laboratoires charges des elements combustibles ont elaborees dans le cadre du programme etabli par le des reacteurs> en vue de mettre au point des aiguilles de combustible pour diverses filieres de reacteurs. Ces aiguilles sont contenues dans des gaines de 5 a 15 mm de diametre, les materiaux utilises etant des aciers inoxydables et des alliages de zirconium, a) Detection de defauts dans les gaines. Examen par ultrasons a l'aide de deux traducteurs immerges. Les tubes sont animes d'un mouvement helicoidal rapide dans un reservoir fixe. Chaque signal de defaut est verifie et enregistre. Pour regler le dispositif et verifier sa stabilite, on utilise comme temoins des fentes'pratiquees a l'arc a la surface des tubes. Dans certains cas, on a egalement recours au controle par courants de Foucault. Les auteurs decrivent deux procedes: l'un, a debit rapide, est fonde sur un systeme de bobines encerclant le tube; l'autre, a exploration heliccfldale, utilise une bobine se deplacant le long du tube. Les signaux fournis par un circuit a pont sont selectionnes selon la phase et filtres, pour des frequences de 30 a 60 kHz. b) Controle des dimensions de tubes et de

  18. New recording methods and electromechanical analysis; Nouvelles methodes d'enregistrement et de depouillement electromecanique des numerations de particules

    Energy Technology Data Exchange (ETDEWEB)

    Meunier, R.; Bonpas, M.; Legrand, J.P. [Commissariat a l' Energie Atomique, Saclay(France). Centre d' Etudes Nucleaires

    1954-07-01

    The measurement that the most often occurs in nuclear physics are of the numerations of pulses representing the transit of a particle in a detector that can be a Geiger counter, a photomultiplier or a pulse chamber. We studied and constructed an electromagnetic recorder who permits to get automatically and without calculation: 1) the activity of a radioelement according to the time; 2) the curve of decrease of a radioelement and its period; 3) any curves of growth or decrease; 4) the activity, at any instant, of a neutron detector; 5) the neutron densities ratios in several points by the method of the detectors. (M.B.) [French] Les mesures qui se presentent le plus souvent en physique nucleaire sont des numerations d'impulsions representant le passage d'une particule dans un detecteur qui peut etre un compteur de Geiger, un photomultiplicateur ou une chambre a impulsions. Nous avons etudie et construit un enregistreur electromagnetique qui permet d'obtenir automatiquement et sans calcul: 1) l'activite d'un radioelement en fonction du temps; 2) la courbe de decroissance d'un radioelement et sa periode; 3) des courbes quelconques de croissance ou de decroissance; 4) l'activite, rapportee a un instant quelconque, d'un detecteur de neutrons; 5) les rapports des densites de neutrons en plusieurs points par la methode des detecteurs. (M.B.)

  19. New recording methods and electromechanical analysis; Nouvelles methodes d'enregistrement et de depouillement electromecanique des numerations de particules

    Energy Technology Data Exchange (ETDEWEB)

    Meunier, R; Bonpas, M; Legrand, J P [Commissariat a l' Energie Atomique, Saclay(France). Centre d' Etudes Nucleaires

    1954-07-01

    The measurement that the most often occurs in nuclear physics are of the numerations of pulses representing the transit of a particle in a detector that can be a Geiger counter, a photomultiplier or a pulse chamber. We studied and constructed an electromagnetic recorder who permits to get automatically and without calculation: 1) the activity of a radioelement according to the time; 2) the curve of decrease of a radioelement and its period; 3) any curves of growth or decrease; 4) the activity, at any instant, of a neutron detector; 5) the neutron densities ratios in several points by the method of the detectors. (M.B.) [French] Les mesures qui se presentent le plus souvent en physique nucleaire sont des numerations d'impulsions representant le passage d'une particule dans un detecteur qui peut etre un compteur de Geiger, un photomultiplicateur ou une chambre a impulsions. Nous avons etudie et construit un enregistreur electromagnetique qui permet d'obtenir automatiquement et sans calcul: 1) l'activite d'un radioelement en fonction du temps; 2) la courbe de decroissance d'un radioelement et sa periode; 3) des courbes quelconques de croissance ou de decroissance; 4) l'activite, rapportee a un instant quelconque, d'un detecteur de neutrons; 5) les rapports des densites de neutrons en plusieurs points par la methode des detecteurs. (M.B.)

  20. Analyse de L'ancrage des Vortex Intergrains pour le Yttrium BARYUM(2) CUIVRE(3) OXYGENE(7) Polycristallin

    Science.gov (United States)

    Fournier, Patrick

    Le Modele de l'Etat Critique Generalise (MECG) est utilise pour decrire les proprietes magnetiques et de transport du YBa_2Cu_3O _7 polycristallin. Ce modele empirique permet de relier la densite de courant critique a la densite de lignes de flux penetrant dans la region intergrain. Deux techniques de mesures sont utilisees pour caracteriser nos materiaux. La premiere consiste a mesurer le champ au centre d'un cylindre creux en fonction du champ magnetique applique pour des temperatures comprises entre 20 et 85K. En variant l'epaisseur de la paroi du cylindre creux, il est possible de suivre l'evolution des cycles d'hysteresis et de determiner des champs caracteristiques qui varient en fonction de cette dimension. En utilisant un lissage des resultats experimentaux, nous determinons J _{co}, H_ {o} et n, les parametres du MECG. La forme des cylindres, avec une longueur comparable au diametre externe, entrai ne la presence d'un champ demagnetisant qui peut etre inclus dans le modele theorique. Ceci nous permet d'evaluer la fraction du volume ecrante, f _{g}, ainsi que le facteur demagnetisant N. Nous trouvons que J_{ co}, H_{o} et f_{g} dependent de la temperature, tandis que n et N (pour une epaisseur de paroi fixe) n'en dependent pas. La deuxieme technique consiste a mesurer le courant critique de lames minces en fonction du champ applique pour differentes temperatures. Nous utilisons un montage que nous avons developpe permettant d'effectuer ces mesures en contact direct avec le liquide refrigerant, i.e. dans l'azote liquide. Nous varions la temperature du liquide en variant la pression du gaz au-dessus du bain d'azote. Cette methode nous permet de balayer des temperatures entre 65K et la temperature critique du materiau ({~ }92K). Nous effectuons le lissage des courbes de courant critique en fonction du champ applique encore a l'aide du MECG, pour a nouveau obtenir ses parametres. Pour trois echantillons avec des traitements thermiques differents, les parametres

  1. A numerical method for solving singular De`s

    Energy Technology Data Exchange (ETDEWEB)

    Mahaver, W.T.

    1996-12-31

    A numerical method is developed for solving singular differential equations using steepest descent based on weighted Sobolev gradients. The method is demonstrated on a variety of first and second order problems, including linear constrained, unconstrained, and partially constrained first order problems, a nonlinear first order problem with irregular singularity, and two second order variational problems.

  2. Dosage of fission products in irradiated fuel treatment effluents (radio-chemical method); Dosage des produits de fission dans les effluents du traitement des combustibles irradies (methode radiochimique)

    Energy Technology Data Exchange (ETDEWEB)

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

    1966-07-01

    The dosage methods presented here are applicable to relatively long-lived fission products present in the effluents resulting from irradiated fuel treatment processes (Sr - Cs - Ce - Zr - Nb - Ru - I). The methods are based on the same principle: - addition of a carrying-over agent - chemical separation over several purification stages, - determination of the chemical yield by calorimetry - counting of an aliquot liquid portion. (author) [French] Les methodes de dosage presentees concernent les produits de fission a vie relativement longue presents dans les effluents de traitement des combustibles irradies (Sr - Cs - Ce - Zr - Nb - Ru - I). Elles sont toutes basees sur le meme principe: - addition d'entraineur, - separation chimique en plusieurs stades de purification, - determination du rendement chimique par calorimetrie, - comptage d'une aliquote liquide. (auteur)

  3. INTERMODALITE ET DEVELOPPEMENT URBAIN DANS L ...

    African Journals Online (AJOL)

    Administrateur

    modalité et l'inter-modalité entre les modes et les services, tout cela offre des .... distances de parcours plus importantes ou l'accès plus restreint au transport collectif en sont .... Ces derniers détiennent 90% du marché en termes. 4 Direction des ... les terminaux national et international de l'aéroport Houari. Boumediene5.

  4. Continuous surveillance of transformers using artificial intelligence methods; Surveillance continue des transformateurs: application des methodes d'intelligence artificielle

    Energy Technology Data Exchange (ETDEWEB)

    Schenk, A.; Germond, A. [Ecole Polytechnique Federale de Lausanne, Lausanne (Switzerland); Boss, P.; Lorin, P. [ABB Secheron SA, Geneve (Switzerland)

    2000-07-01

    The article describes a new method for the continuous surveillance of power transformers based on the application of artificial intelligence (AI) techniques. An experimental pilot project on a specially equipped, strategically important power transformer is described. Traditional surveillance methods and the use of mathematical models for the prediction of faults are described. The article describes the monitoring equipment used in the pilot project and the AI principles such as self-organising maps that are applied. The results obtained from the pilot project and methods for their graphical representation are discussed.

  5. Etude comparee de l'efficacite de trois methodes de prévention des ...

    African Journals Online (AJOL)

    L'élevage de la pintade se heurte à de nombreuses contraintes touchant principalement la santé des pintadeaux. Des mortalités des pintadeaux et des pintades sont fréquemment enregistrées dans les élevages. Afin de proposer une ou des méthodes de lutte efficaces, cette étude conduite au nord Togo a eu comme ...

  6. Study of the fluctuations of the partial and total radiative widths by neutron capture resonance method; Etude des fluctuations des largeurs radiatives partielles et totales par la capture des neutrons de resonance

    Energy Technology Data Exchange (ETDEWEB)

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

    1965-06-01

    Radiative capture experiments by neutron time-of-flight methods have been made for following studies: distribution of partial radiative widths, effects of correlation between different radiative transitions, fluctuations of total radiative widths {gamma}{sub {gamma}} from resonance to resonance, variation of {gamma}{sub {gamma}} with number of mass and the search for the existence of potential capture. Also, some other experiments with the use of neutron capture gamma-rays spectra have been investigated. (author) [French] Par la capture des neutrons de resonance dont les energies sont selectionnees a l'aide de la technique du temps de vol, differents types d'experiences ont ete realisees concernant les etudes des distributions des largeurs radiatives partielles, des effets de correlation entre differentes voies de desexcitation, de la fluctuation des largeurs radiatives totales {gamma}{sub {gamma}} de resonance a resonance, de la variation de la quantite {gamma}{sub {gamma}} en fonction du nombre de masse et de la mise en evidence de l'existence du processus de capture potentielle. Quelques autres applications de l'emploi du spectre de rayons gamma ont egalement ete presentees. (auteur)

  7. Study of the fluctuations of the partial and total radiative widths by neutron capture resonance method; Etude des fluctuations des largeurs radiatives partielles et totales par la capture des neutrons de resonance

    Energy Technology Data Exchange (ETDEWEB)

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

    1965-06-01

    Radiative capture experiments by neutron time-of-flight methods have been made for following studies: distribution of partial radiative widths, effects of correlation between different radiative transitions, fluctuations of total radiative widths {gamma}{sub {gamma}} from resonance to resonance, variation of {gamma}{sub {gamma}} with number of mass and the search for the existence of potential capture. Also, some other experiments with the use of neutron capture gamma-rays spectra have been investigated. (author) [French] Par la capture des neutrons de resonance dont les energies sont selectionnees a l'aide de la technique du temps de vol, differents types d'experiences ont ete realisees concernant les etudes des distributions des largeurs radiatives partielles, des effets de correlation entre differentes voies de desexcitation, de la fluctuation des largeurs radiatives totales {gamma}{sub {gamma}} de resonance a resonance, de la variation de la quantite {gamma}{sub {gamma}} en fonction du nombre de masse et de la mise en evidence de l'existence du processus de capture potentielle. Quelques autres applications de l'emploi du spectre de rayons gamma ont egalement ete presentees. (auteur)

  8. Method of evaluation of radiant heat transfers for geometries having cast shadows; Methode d`evaluation des echanges radiatifs pour des geometries comportant des ombres portees

    Energy Technology Data Exchange (ETDEWEB)

    Lair, P; Millan, P [ONERA-CERT/DERMES, 31 - Toulouse (France); Dumoulin, J [INSA-UPS, LETHEM, 31 - Toulouse (France)

    1997-12-31

    Experimental studies on aero-thermal characterization of various flows are carried out by the CERT/DERMES centre of the French national office of aerospace studies and research (ONERA). The measurement is based on the infrared thermography method which requires a correction of surface fluxes. This correction is necessarily based on a radiative statement of the cell where the flow takes place. A numerical method of form factors calculation in complex geometrical configuration has been developed. This method is applicable to surfaces (flat or not) and takes into account the shadow phenomena as they can exist inside an experimental test path. Two methods of radiative statements have been developed and compared. The influence of form factors calculation on the radiative statement is also analyzed and the problem of the sensitivity of the methods with respect to possible measurement errors is evoked. (J.S.) 8 refs.

  9. Method of evaluation of radiant heat transfers for geometries having cast shadows; Methode d`evaluation des echanges radiatifs pour des geometries comportant des ombres portees

    Energy Technology Data Exchange (ETDEWEB)

    Lair, P.; Millan, P. [ONERA-CERT/DERMES, 31 - Toulouse (France); Dumoulin, J. [INSA-UPS, LETHEM, 31 - Toulouse (France)

    1996-12-31

    Experimental studies on aero-thermal characterization of various flows are carried out by the CERT/DERMES centre of the French national office of aerospace studies and research (ONERA). The measurement is based on the infrared thermography method which requires a correction of surface fluxes. This correction is necessarily based on a radiative statement of the cell where the flow takes place. A numerical method of form factors calculation in complex geometrical configuration has been developed. This method is applicable to surfaces (flat or not) and takes into account the shadow phenomena as they can exist inside an experimental test path. Two methods of radiative statements have been developed and compared. The influence of form factors calculation on the radiative statement is also analyzed and the problem of the sensitivity of the methods with respect to possible measurement errors is evoked. (J.S.) 8 refs.

  10. Characterization of heterogeneous reservoirs: sentinels method and quantification of uncertainties; Caracterisation des reservoirs heterogenes: methode des sentinelles et quantification des incertitudes

    Energy Technology Data Exchange (ETDEWEB)

    Mezghani, M.

    1999-02-11

    The aim of this thesis is to propose a new inversion method to allow both an improved reservoir characterization and a management of uncertainties. In this approach, the identification of the permeability distribution is conducted using the sentinel method in order to match the pressure data. This approach, based on optimal control theory, can be seen as an alternative of least-squares method. Here, we prove the existence of exact sentinels under regularity hypothesis. From a numerical point of view, we consider regularized sentinels. We suggest a novel approach to update the penalization coefficient in order to improve numerical robustness. Moreover, the flexibility of the sentinel method enables to develop a way to treat noisy pressure data. To deal with geostatistical modelling of permeability distribution, we propose to link the pilot point method with sentinels to reach the identification of permeability. We particularly focus on the optimal location of pilot points. Finally, we present an original method, based on adjoint state computations, to quantify the dynamic data contribution to the characterisation of a calibrated geostatistical model. (author) 67 refs.

  11. The application of {beta}-ray excitation fluorescence to the measurement of the thickness of deposits and to analysis; Applications de la fluorescence excitee au moyen des rayons {beta} a la mesure des epaisseurs des depots et a l'analyse

    Energy Technology Data Exchange (ETDEWEB)

    Martinelli, P [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires; Seibel, G [Institut de Recherches de la Siderurgie Francaise (IRSID), 78 - Saint-Germain-en-Laye (France)

    1961-07-01

    Principles of the method are first outlined and the instrumentation used is described. The different types of radiation detectors are subject of a detailed study. As a source of {beta}-radiation {sup 90}(Sr + Y) was used as well as {sup 147}Pm. Great care was taken to eliminate back-diffused electrons by deflection by a strong permanent magnet. The method was applied to the measurement of the thickness of deposits of Cr, Zn, Sn, Cd and Cu on iron as well as Zn, Cr, Ag and Au on copper and the results obtained are discussed. An attempt was made, to use {beta}-X-ray fluorescence for the analysis of minerals, iron ore and glass and for routine control of Si-Mn, Si-Ca, Fe-Mn and Fe-W. Finally the method of {beta}-X-ray fluorescence is compared with normal-X-ray fluorescence and possibilities of further development are cited. (author) [French] Les principes de la methode et l'instrumentation utilisee sont presentes. On decrit en particulier les detecteurs de rayonnement utilises. Comme source de rayonnement on utilise {sup 90}(Sr + Y) et {sup 147}Pm. Pour eliminer les electrons retrodiffuses on utilise un aimant permanent place sur le trajet du faisceau. La methode est appliquee a la mesure des epaisseurs des depots metalliques tels que le Cr, Zn, Sn, Cd et Cu sur fer et le Zn, Cr, Ag et Au sur cuivre. D'autre part, la fluorescence {beta}-X etait utilisee pour l'analyse des minerais et des verres et pour le controle des alliages Fe-Mn, Fe-W, Si-Mn, Si-Ca. Enfin, on passe a une comparaison entre la fluorescence {beta}-X et la fluorescence X normale et on discute les possibilites d'un developpement futur. (auteur)

  12. Determination of the food consumption in eleven regions of the european community with a view to studying the radioactive contamination level: Methods used. Results of family enquiries; Determination des regimes alimentaires des populations de onze regions de la communaute europeenne en vue de l'etude des niveaux de contamination radioactive: Methodologie. Resultats des enquetes familiales

    Energy Technology Data Exchange (ETDEWEB)

    Cresta, M; Lacourly, G [Commissariat a l' Energie Atomique, Fontenay-aux-Roses (France). Centre d' Etudes Nucleaires

    1966-07-01

    In the present report are given the results obtained from food surveys carried out during the period 1963-1965 and involving 9000 families living in eleven regions spread out over the six European Community countries. A partial analysis of the results obtained covers a reduced sample of 3725 families; it makes it possible to fix the composition of the mean individual, monthly and annual food consumptions for each of the eleven regions. Details of the organisation of the survey, of the data processing methods and of the method of presenting the results are given in the first part of the report. the second part presents, in numerical table form, the consumption of various foodstuffs and the feeding principles for each region covered by the survey. Tables summarizing the data make it possible to compare the mean individual consumptions in the various regions studied. (author) [French] Dans le present rapport sont rassembles les premiers resultats des enquetes alimentaires effectuees pendant la periode 1963-1965, aupres de 9000 familles, dans onze regions reparties dans les six pays de la Communaute Europeenne. L'exploitation partielle des donnees obtenues porte sur un echantillon reduit a 3725 familles et permet d'etablir la composition du regime alimentaire moyen individuel, mensuel et annuel de chacune des onze regions. L'organisation des enquetes, la methode de traitement des donnees et l'expression des resultats sont exposees dans la premiere partie du rapport. La seconde reunit, sous forme de tableaux numeriques, les consommations des differents aliments et principes alimentaires par region d'enquetes. Des tableaux recapitulatifs permettent, en outre, une comparaison des consommations moyennes, individuelles des differentes regions etudiees. (auteur)

  13. Determination of the food consumption in eleven regions of the european community with a view to studying the radioactive contamination level: Methods used. Results of family enquiries; Determination des regimes alimentaires des populations de onze regions de la communaute europeenne en vue de l'etude des niveaux de contamination radioactive: Methodologie. Resultats des enquetes familiales

    Energy Technology Data Exchange (ETDEWEB)

    Cresta, M.; Lacourly, G. [Commissariat a l' Energie Atomique, Fontenay-aux-Roses (France). Centre d' Etudes Nucleaires

    1966-07-01

    In the present report are given the results obtained from food surveys carried out during the period 1963-1965 and involving 9000 families living in eleven regions spread out over the six European Community countries. A partial analysis of the results obtained covers a reduced sample of 3725 families; it makes it possible to fix the composition of the mean individual, monthly and annual food consumptions for each of the eleven regions. Details of the organisation of the survey, of the data processing methods and of the method of presenting the results are given in the first part of the report. the second part presents, in numerical table form, the consumption of various foodstuffs and the feeding principles for each region covered by the survey. Tables summarizing the data make it possible to compare the mean individual consumptions in the various regions studied. (author) [French] Dans le present rapport sont rassembles les premiers resultats des enquetes alimentaires effectuees pendant la periode 1963-1965, aupres de 9000 familles, dans onze regions reparties dans les six pays de la Communaute Europeenne. L'exploitation partielle des donnees obtenues porte sur un echantillon reduit a 3725 familles et permet d'etablir la composition du regime alimentaire moyen individuel, mensuel et annuel de chacune des onze regions. L'organisation des enquetes, la methode de traitement des donnees et l'expression des resultats sont exposees dans la premiere partie du rapport. La seconde reunit, sous forme de tableaux numeriques, les consommations des differents aliments et principes alimentaires par region d'enquetes. Des tableaux recapitulatifs permettent, en outre, une comparaison des consommations moyennes, individuelles des differentes regions etudiees. (auteur)

  14. Contribution to the development of a multi-mode measurement system for dynamic neutronic measurements and processing of the related uncertainties; Contribution au developpement d'un systeme de mesure multimode pour des mesures neutroniques dynamiques et traitement des incertitudes associees

    Energy Technology Data Exchange (ETDEWEB)

    Geslot, B

    2006-11-15

    It is difficult to estimate integral reactor parameters, especially reactivity, in deeply subcritical cores. Indeed the standard neutronic methods have been designed for near critical reactivity levels and they often need a critical reference. This thesis takes part in the research on ADS (Accelerated Driven Systems), for which the multiplication coefficient would be about 0.95. The first part of the thesis deals with the development of the XMODE system. It is a flexible measurement system dedicated to experiments in neutronics. X-MODE is capable of acquiring logical signals particularly in time-stamping mode as well as analogical signals. The second part of the thesis presents a statistical study of the methods used to analyse flux transients. Indeed a lot of methods exist to analyse flux transients and some are little known. Means to estimate characteristics of reactivity estimators are provided, methods compared and recommendations made. Finally, the dynamic measurements of the TRADE program are analysed and discussed. During this program, three subcritical configurations were explored. It appears that pulsed neutron source experiments give reactivity estimations that are much more precise than those obtained from flux transients. (author)

  15. Development of wind energy in Morocco; Developpement de l'energie eolienne au Maroc

    Energy Technology Data Exchange (ETDEWEB)

    Enzili, M. [Centre de Developpement des Energies Renouvelables de Maroc, Rabat (Morocco)

    2008-04-15

    Morocco's national energy policy includes the use of renewable energy sources to lessen its reliance on fossil fuels such as coal and oil. Legislation was recently passed to increase the threshold of electrical power from 10 MW to 50 MW. Solar and wind energy are the most abundant renewable energy resources in the country and are recommended for exploitation on a large scale. Feasibility studies conducted by the Centre de Developpement des Energies Renouvelables have shown that Morocco has enough wind energy to produce electricity on a large scale and interconnect it with the national power grid. Wind energy in the country could also be used for on-site power generation in remote villages or for desalination of seawater, particularly in the southern regions of Morocco which are most affected by drought. Essaouira, Tangier, Tetouan, Tarfaya, Dakhla, Laayoune and Taza were among the regions identified with significant wind resources. The total wind energy potential for Morocco is estimated to be 2,650 GW, while the technical wind energy potential is estimated to be 1,600 GW. Several projects have been realized in the areas of electricity production, interconnection to the national power grid, decentralized rural electrification and eventually the introduction of water pumping. It was concluded that exporting green energy to Europe, via the Morocco-Spain route after the restructuring of Morocco's electricity sector will create a viable market for the medium and long-term. 3 figs.

  16. Development and featuring of hemispherical photomultipliers for cosmic ray detection - calibration of surface detectors and analysis of horizontal showers at the Pierre Auger Observatory; Developpement et caracterisation de photomultiplicateurs hemispheriques pour les experiences d'astroparticules - etalonnage des detecteurs de surface et analyse des gerbes horizontales de l'Observatoire Pierre Auger

    Energy Technology Data Exchange (ETDEWEB)

    Dornic, D

    2006-09-15

    The large photomultipliers (PMT) are currently used in astro-particle and neutrino experiments where they have to detect low levels of light. We have studied and characterised large PMTs developed by the PHOTONIS Group Company. The first part of this thesis is dedicated to the full characterization of two types of multipliers currently used in large PMTs. Then, we present results of a new photocathode process, applied on the XPI805 (PMT used in the Pierre Auger Observatory) in order to improve the quantum efficiency. Finally, we study the PMT diameter influence on main parameters (5, 8 and 10 inches). The second part is devoted to the study of the water Cerenkov tank (WCD) response to the shower particles and the horizontal air showers analysis with the Pierre Auger Observatory. The main parameters of a WCD simulation developed in the Auger IPN group were calibrated with several measurements on vertical and inclined muons, performed on dedicated test tanks. The kind of detector used in the surface detector allows detecting very inclined events with a good sensitivity (zenith angle superior to 70 degrees). We have established specific methods to analyze these events (selection and reconstruction). These methods were applied to the Auger data in order to obtain the energy spectrum of the horizontal events. Finally, we detailed two methods to test directly the hadronic models predictions by studying the air showers muonic component. (author)

  17. Development and featuring of hemispherical photomultipliers for cosmic ray detection - calibration of surface detectors and analysis of horizontal showers at the Pierre Auger Observatory; Developpement et caracterisation de photomultiplicateurs hemispheriques pour les experiences d'astroparticules - etalonnage des detecteurs de surface et analyse des gerbes horizontales de l'Observatoire Pierre Auger

    Energy Technology Data Exchange (ETDEWEB)

    Dornic, D

    2006-09-15

    The large photomultipliers (PMT) are currently used in astro-particle and neutrino experiments where they have to detect low levels of light. We have studied and characterised large PMTs developed by the PHOTONIS Group Company. The first part of this thesis is dedicated to the full characterization of two types of multipliers currently used in large PMTs. Then, we present results of a new photocathode process, applied on the XPI805 (PMT used in the Pierre Auger Observatory) in order to improve the quantum efficiency. Finally, we study the PMT diameter influence on main parameters (5, 8 and 10 inches). The second part is devoted to the study of the water Cerenkov tank (WCD) response to the shower particles and the horizontal air showers analysis with the Pierre Auger Observatory. The main parameters of a WCD simulation developed in the Auger IPN group were calibrated with several measurements on vertical and inclined muons, performed on dedicated test tanks. The kind of detector used in the surface detector allows detecting very inclined events with a good sensitivity (zenith angle superior to 70 degrees). We have established specific methods to analyze these events (selection and reconstruction). These methods were applied to the Auger data in order to obtain the energy spectrum of the horizontal events. Finally, we detailed two methods to test directly the hadronic models predictions by studying the air showers muonic component. (author)

  18. Monetary valorization of the sanitary and environmental impacts of a nuclear accident: synthesis of ''ExternE'' studies, interests and limits of complementary developments; Valorisation monetaire des impacts sanitaires et environnementaux d'un accident nucleaire: synthese des etudes externe, interets et limites de developpements complementaires

    Energy Technology Data Exchange (ETDEWEB)

    Schieber, C.; Schneider, Th

    2002-09-01

    This document constitutes a synthesis of the various available methods for the monetary evaluation of the nuclear accidents impacts in order to reveal the already evaluated impacts, those which need complementary developments and those for which the monetary approach currently seems to come up against limits. It is based primarily on the approach realized by the ''ExternE'' project of the European Commission, consisting in the evaluation of the external costs of the nuclear energy industry. (A.L.B.)

  19. An approach to automated chromosome analysis; Etudes pour une methode d'automatisation des analyses chromosomiques

    Energy Technology Data Exchange (ETDEWEB)

    Le Go, Roland

    1972-05-03

    The methods of approach developed with a view to automatic processing of the different stages of chromosome analysis are described in this study divided into three parts. Part 1 relates the study of automated selection of metaphase spreads, which operates a decision process in order to reject ail the non-pertinent images and keep the good ones. This approach has been achieved by Computing a simulation program that has allowed to establish the proper selection algorithms in order to design a kit of electronic logical units. Part 2 deals with the automatic processing of the morphological study of the chromosome complements in a metaphase: the metaphase photographs are processed by an optical-to-digital converter which extracts the image information and writes it out as a digital data set on a magnetic tape. For one metaphase image this data set includes some 200 000 grey values, encoded according to a 16, 32 or 64 grey-level scale, and is processed by a pattern recognition program isolating the chromosomes and investigating their characteristic features (arm tips, centromere areas), in order to get measurements equivalent to the lengths of the four arms. Part 3 studies a program of automated karyotyping by optimized pairing of human chromosomes. The data are derived from direct digitizing of the arm lengths by means of a BENSON digital reader. The program supplies' 1/ a list of the pairs, 2/ a graphic representation of the pairs so constituted according to their respective lengths and centromeric indexes, and 3/ another BENSON graphic drawing according to the author's own representation of the chromosomes, i.e. crosses with orthogonal arms, each branch being the accurate measurement of the corresponding chromosome arm. This conventionalized karyotype indicates on the last line the really abnormal or non-standard images unpaired by the program, which are of special interest for the biologist. (author) [French] Ce travail expose les methodes d'approche etudiees en vue

  20. Development of a unified sizing method for gas radiation heating facilities used in large-volume buildings; Developpement d'une methode de dimensionnement unifiee d'installations de chauffage radiant gaz pour les batiments de grand volume

    Energy Technology Data Exchange (ETDEWEB)

    Jimenez, M.; Bego, L.; Douls, Y.; Le Dean, P.; Paradowski, V. [Gaz de France, GDF, Dir. de la Recherche, 75 - Paris (France)

    2000-07-01

    Builders now have perfect command of the natural gas heating technique used for large-volume buildings. However, the sizing of heating facilities still leaves grounds for discussion, whatever the energies actually used. Accordingly, between 1997 and 1999, the ATG (technical association of the Gas industry in France), seven French manufacturers of 'large volume' heating equipment, the Chaleur Et Rayonnement (CER) association and Gaz de France decided to collaborate and develop a 'unified sizing method' for heating facilities using radiating emitters. During the first year of the study, the above partners worked on the said method (theoretical thermal study of the radiative phenomena, and then adaptation to the methods currently used by the various manufacturers). In 1998, with the support of the ADEME (the French environment and energy control agency), the partners tested the method on five industrial buildings (studying the thermal behavior and making air renewal measurements with search gases). This work made it possible to either confirm or adapt the theoretical evaluations which had been made originally. In 1999, a software program was produced to make the developed method more user friendly. The program can be used to determine the power to be installed, but also to assess the quality of the chosen configuration of the emitters (unit power, inclination, orientation) for optimum customer comfort. (authors)

  1. 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

    The expansion of a nuclear economy entails the development of fuel process and reprocessing plant programmes. The model proposed makes it possible to select the size, the site and the start-up schedule of the plants in such a way as to minimize the total freight and reprocessing costs. As an illustration, we have approached the problem of burnt natural uranium processing plants related to natural uranium-graphite as nuclear power stations. The sites and annual output of the reactors, the possible plant sites and cost functions (freight and reprocessing) are supposed to be known. The method consists in first approaching the process plant problem as a Dynamic Programming problem, increasing programme slices (total reactor output) being explored sequentially. When the quantities of burnt natural uranium to be reprocessed are fixed, the minimization of the transport cost is then also carried out as a dynamic programming problem. The neighbourhood of the optimum process cost is explored in order to find the minimum summation of a suboptimal processing cost and corresponding optimal transport cost. As the reprocessing problem can be represented on a sequential graph, in order to compute the sub-optima, we developed and used a 'reflexion algorithm'. The method can be interpreted as a general mechanism for determining the optimum when to a sequential dynamic problem (for example an equipment programme) is added a complementary problem (transport, for instance). It also makes it possible to estimate the economic losses which result from the choice of a non optimal policy for other than economic reasons. (author) [French] L'expansion de l'economie nucleaire se traduit par un developpement des programmes d'usines d'elaboration et de retraitement des combustibles. Le modele propose permet de choisir la taille, la localisation et la cadence de mise en service des usines de maniere a minimiser le total des frais de transport et de retraitement. A titre d'exemple nous avons

  2. Contribution to the automatic command in robotics - Application to the command by microprocessors of the articulated systems; Contribution a la commande automatique en robotique. Application a la commande par microprocesseurs des manipulateurs articules

    Energy Technology Data Exchange (ETDEWEB)

    Al Mouhamed, Mayez

    1982-01-29

    The first part of the present paper deals with the main methods of changing the coordinates for a general articulated system. After a definition of the coordinates changing, we propose a coordination system designed for easy programming of the movements. Its characteristic is to permit the action anywhere on the manipulated object. The second part deals with the force regulation problem. For this purpose we have developed a general force sensor. The informations delivered by the sensor are used by force regulators which are intended for the automatic assembly of subsystems. In the third part the dynamic problem of the articulated systems is exposed. We present a new method which allows to determine dynamic parameters from appropriate motions of the robot. These parameters are then used to implement the dynamic control. Several applications, using the powerful microprocessor INTEL 8086 and its arithmetic coprocessor 8087, are presented, in order to demonstrate the performances gained. (author) [French] Dans la premiere partie de ce memoire, nous exposons les principales methodes de changement de coordonnees pour un systeme articule general. Apres une definition adequate de ce dernier, nous proposons un systeme de coordination permettant une programmation facile des mouvements. Sa caracteristique est de prendre comme centre d'action un point quelconque de l'objet manipule. Dans la deuxieme partie, nous etudions la regulation en effort. Pour cela nous avons developpe un capteur de forces general. Les informations que delivre ce dernier sont utilisees par des regulateurs d'effort adaptes au contexte de l'assemblage automatique des pieces. Dans la troisieme partie, nous exposons une nouvelle methode de commande dynamique des systemes articules. Nous obtenons des parametres dynamiques du robot a partir de mouvements appropries. Ces derniers sont ensuite utilises dans l'elaboration des commandes. Des applications utilisant le microprocesseur INTEL 8086 avec son

  3. 47 Analyse des images satellitales radar RSO-ERS et optique ETM+ ...

    African Journals Online (AJOL)

    PR BOKO

    Des cartes à plus grande échelle au 1/100 000 ont aussi dressées, dans le cadre du projet de coopération géologique ivoiro- allemenande [5, 6]. ..... [13] - SOCIETE POUR LE DEVELOPPEMENT MINIER IVOIRIEN (SODEMI), "Carte photo-géologique à 1/200 000, feuille de Tienko-Odienné", (1978). [14] - K. POTHIN et A.

  4. Methods of measuring floor resistance; Messverfahren zur Bestimmung des Ableitwiderstandes von Fussboeden

    Energy Technology Data Exchange (ETDEWEB)

    Seemann, A. [BGFW Berufsgenossenschaft der Gas-, Fernwaerme- und Wasserwirtschaft, Duesseldorf (Germany); Tutschek, G.; Warszewski, P. [Ruhrgas AG, Essen (Germany). Abt. Anlagensicherheit

    2001-04-01

    In gas fitting plants where explosive gas/air mixtures can occur the flooring materials must be conductive. Persons who are insulated from earth can easily acquire and retain an electrostatic charge. If an electrostatically charged person touches a conducting object (e.g. pipe, gas fitting plant) a spark occur at the point of contact. Such sparks can cause ignition of an explosive gas/air mixture. To avoid the retention of static electricity the recommended level of the earth of a floor must be lower than 10{sup 8} {omega} and the persons have to wear dissipative footwear. In several standards methods for checking floor resistance are described. A useful test method is given in DIN EN 1081. (orig.) [German] Explosionsfaehige Erdgas-/Luftgemische koennen durch elektrostatische Entladungsfunken gezuendet werden. Um eine elektrostatische Aufladung von Personen zu vermeiden, darf der Ableitwiderstand des Fussbodens den Wert von 10{sup 8} {omega} nicht ueberschreiten, und es muss ableitfaehiges Schuhwerk getragen werden. In verschiedenen Normen sind Messerfahren fuer die Ueberpruefung des Ableitwiderstandes von verlegten Fussboeden angegeben. Eine fuer die Praxis brauchbare Messmethode wird in DIN EN 1081 angegeben. (orig.)

  5. Comparison of some methods for analyzing the optical properties of molecular aggregates; Comparaison de quelques methodes d'analyse des proprietes optiques des agregats moleculaires

    Energy Technology Data Exchange (ETDEWEB)

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

    1965-07-01

    This report compares the application both of the exciton theory and of the polarizability theory to the study of the optical properties of dimers made up of two identical molecules having only one excited level when separate, and which are held together in the dimer only by Van der Waals forces to the exclusion of any covalent bonding. Using this theoretical basis, the author gives an interpretation of the changes in the spectrum of aqueous NN' diethyl-cyanine solutions as a function of concentration, and stresses the present lack of experimental data necessary for understanding of the mechanism of the hypochromia of nucleic acids. (author) [French] Ce rapport compare l'application, d'une part de la theorie des excitons, d'autre part de la theorie des polarisabilites a l'etude des proprietes optiques de dimeres composees de deux molecules identiques ne possedant, lorsqu'elles sont prises isolement, qu'un seul niveau excite, et qui sont unies l'une a l'autre, au sein du dimere, par des forces de Van der Waals a l'exclusion de toute liaison covalente. Sur ces bases theoriques, l'auteur donne une interpretation de l'evolution du spectre de solutions aqueuses de NN' diethylcyanine en fonction de la concentration et souligne l'insuffisance actuelle des donnees experimentales necessaires a la comprehension du mecanisme de l'hypochromisme des acides nucleiques. (auteur)

  6. Radioactive beams produced by the ISOL method: development for laser ionization and for surface ionization; Faisceaux exotiques par methode ISOL: developpements pour l'ionisation par laser et l'ionisation de surface

    Energy Technology Data Exchange (ETDEWEB)

    Hosni, Faouzi

    2004-10-01

    The works were carried out in the framework of the research program PARRNe (production of radioactive neutron-rich nuclei). This program aims to determine optimal conditions to produce intense beams of neutron-rich isotopes. This thesis treats multiple technical aspects related to the production of separate radioactive isotopes in line (ISOL). It deals mainly with the development of the target-source unit which is the key element for projects such as SPIRAL-2 or EURISOL.The first part presents the various methods using fission as production mode and compares them: fission induced by thermal neutrons, induced by fast neutrons and photofission. The experiment carried out at CERN validated the interest of the photofission as a promising production mode of radioactive ions. That is why the institute of nuclear physics of Orsay decided to build a linear electron accelerator at the Tandem d'Orsay (ALTO).The second part of this thesis deals with the development of uranium targets. The X-rays diffraction and Scanning Electron Microscopy have been used as analysis techniques. They allowed to determine the chemical and structural characteristics of uranium carbide targets as function of various heating temperatures. After the production, the process of ionization has been studied. Two types of ion source have been worked out: the first one is a surface ion source and the second one is a source based on resonant ionization by laser. These two types of sources will be used for the ALTO project. (author)

  7. Methods for studying the radioactive contamination of plants (1963); Methodes d'etude de la contamination radioactive des vegetaux (1963)

    Energy Technology Data Exchange (ETDEWEB)

    Coulon, R; Jeanmaire, L; Michon, G [Commissariat a l' Energie Atomique, Fontenay-aux-Roses (France). Centre d' Etudes Nucleaires

    1963-07-01

    The authors first define the doctrine which led to the devising of a method for studying the radioactive pollution of plants, based on the use of simple techniques, having the possibility of being adapted for routine work, and so devised that each stage is proceeded with only if the preceding one justifies it. For each stage a study is effected comparing the results obtained by the use of more exact techniques. The second part describes in detail the techniques used. (authors) [French] Dans une premiere partie lea auteurs definissent la doctrine qui leur a permis d'elaborer une methode d'etude de la pollution radioactive des vegetaux, basee sur l'utilisation de techniques simples, se pretant au travail de serie et concues de telle maniere que chaque etape n'est abordee que si la precedente le justifie. Chaque etape fait l'objet d'une etude qui compare les resultats a ceux obtenue par des techniques plus precises. La deuxieme partie decrit dans le detail les techniques utilisees. (auteurs)

  8. Comparison between ARIMA and DES Methods of Forecasting Population for Housing Demand in Johor

    Directory of Open Access Journals (Sweden)

    Alias Ahmad Rizal

    2016-01-01

    Full Text Available Forecasting accuracy is a primary criterion in selecting appropriate method of prediction. Even though there are various methods of forecasting however not all of these methods are able to predict with good accuracy. This paper presents an evaluation of two methods of population forecasting for housing demand. These methods are Autoregressive Integrated Moving Average (ARIMA and Double Exponential Smoothing (DES. Both of the methods are principally adopting univariate time series analysis which uses past and present data for forecasting. Secondary data obtained from Department of Statistics, Malaysia was used to forecast population for housing demand in Johor. Forecasting processes had generated 14 models to each of the methods and these models where evaluated using Mean Absolute Percentage Error (MAPE. It was found that 14 of Double Exponential Smoothing models and also 14 of ARIMA models had resulted to 1.674% and 5.524% of average MAPE values respectively. Hence, the Double Exponential Smoothing method outperformed the ARIMA method by reducing 4.00 % in forecasting model population for Johor state. These findings help researchers and government agency in selecting appropriate forecasting model for housing demand.

  9. The determination methods of the velocity constant for electrochemical reactions; Les methodes de determination de la constante de vitesse des reactions electrochimiques

    Energy Technology Data Exchange (ETDEWEB)

    Molina, R

    1963-07-01

    In a brief introduction are recalled the fundamental mechanisms of the electrochemical reaction and the definition of the intrinsic velocity constant of a such reaction. By the nature of the different parameters which enter in this definition are due some experimental problems which are examined. Then are given the principles of the measurement methods of the velocity constant. These methods are developed with the mathematical expression of the different rates of the mass transfer to an electrode. In each case are given the experimental limits of use of the methods and the size order of the velocity constant that can be reached. A list of fundamental works to be consulted conclude this work. (O.M.) [French] Dans une breve introduction sont rappeles les mecanismes fondamentaux de la reaction electrochimique et la definition de la constante de vitesse intrinseque d'une telle reaction. De la nature des differents parametres qui entrent dans celle definition, decoulent un certain nombre de problemes experimentaux qui sont passes en revue. On donne ensuite les principes des methodes de mesure de la constante de vitesse. L'exposition de ces methodes est developpee a l'aide de l'expression mathematique des differents regimes de transfert de masse a une electrode. On s'attache dans chaque cas, a donner les limitations experimentales d'utilisation des methodes et l'ordre de grandeur de la constante de vitesse qu'elles permettent d'atteindre. Une liste des ouvrages fondamentaux a consulter conclut ce travail. (auteur)

  10. Sports, genre et developpement durable : l'heritage d'une ...

    African Journals Online (AJOL)

    Sports, genre et developpement durable : l'heritage d'une distribution ... to new populations in situation of confrontation with the difference that Goffman (1975) ... and women (gender), maintain the sports field and behind the appearance of a ...

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1960-07-01

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

  12. Method of chemical analysis of silicate rocks (1962); Methode d'analyse chimique des roches silicatees (1962)

    Energy Technology Data Exchange (ETDEWEB)

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

    1962-07-01

    A rapid method of analysis for the physical and chemical determination of the major constituents of silicate rocks is described. Water losses at 100 deg. C and losses of volatile elements at 1000 deg. C are estimated after staying in oven for these temperatures, or by mean of a thermo-balance. The determination of silica is made by a double insolubilization with hydrochloric acid on attack solution with sodium carbonate; total iron and aluminium, both with calcium and magnesium, after ammoniacal precipitation of Fe and Al, are determined on the filtration product of silica by titrimetry-photometry of their complexes with EDTA. The alkalis Na and K by flame spectrophotometry, Mn by colorimetry of the permanganate, and Ti by mean of his complex with H{sub 2}O{sub 2}, are determined on fluosulfuric attack solution. Phosphorus is determined by his complex with 'molybdenum blue' on a fluoro-nitro-boric attack solution; iron is estimated by potentiometry, with the help of bichromate on hydrofluoric solution. (author) [French] Une methode d'analyse rapide est decrite pour la determination physico-chimique des constituants principaux des roches silicatees. Les pertes en eau a 100 deg. C et en matieres volatiles a 1000 deg. C sont evaluees apres passage au four a ces temperatures, ou a l'aide d'une thermobalance. La determination de la silice se fait par double insolubilisation a l'acide chlorhydrique, sur une attaque au carbonate de sodium; le fer total et l'aluminium ainsi que le calcium et le magnesium, apres precipitation a l'ammoniaque des deux premiers metaux, sont determines sur le filtrat de la silice par titrimetrie-photometrie de leurs complexes avec l'E.D.T.A. Les alcalins sodium et potassium par spectrophotometrie de flamme, le manganese par colorimetrie du permanganate, le titane a l'aide de son complexe avec l'eau oxygenee, sont determines sur une attaque fluosulfurique. Le phosphore est determine par son complexe du 'bleu de molybdene' sur une attaque fluo

  13. The neutronic method for measuring soil moisture; La methode neutronique de mesure de l'humidite des sols

    Energy Technology Data Exchange (ETDEWEB)

    Couchat, Ph [Commissariat a l' Energie Atomique, Cadarache (France). Centre d' Etudes Nucleaires

    1967-07-01

    The three group diffusion theory being chosen as the most adequate method for determining the response of the neutron soil moisture probe, a mathematical model is worked out using a numerical calculation programme with Fortran IV coding. This model is fitted to the experimental conditions by determining the effect of different parameters of measuring device: channel, fast neutron source, detector, as also the soil behaviour under neutron irradiation: absorbers, chemical binding of elements. The adequacy of the model is tested by fitting a line through the image points corresponding to the couples of experimental and theoretical values, for seven media having different chemical composition: sand, alumina, line stone, dolomite, kaolin, sandy loam, calcareous clay. The model chosen gives a good expression of the dry density influence and allows {alpha}, {beta}, {gamma} and {delta} constants to be calculated for a definite soil according to the following relation which gives the count rate of the soil moisture probe: N = ({alpha} {rho}{sub s} +{beta}) H{sub v} +{gamma} {rho}{sub s} + {delta}. (author) [French] La theorie a trois groupes etant choisie comme le moyen le plus adequat pour determiner la reponse de l'humidimetre, une mise en forme d'un modele mathematique est effectuee grace a un programme de calcul numerique ecrit en code Fortran IV. Cette representation est adaptee a l'experience par l'etude de l'influence de parametres du systeme de mesure: tubage, source, detecteur, et du comportement du sol vis-a-vis des neutrons: presence d'absorbeurs, liaison chimique des elements. La validite du modele est testee par ajustement d'une droite aux points images des couples de valeurs experimentales et theoriques, ceci pour sept milieux distincts definis par leur composition chimique: sable, alumine, calcaire, dolomie, kaolin, limon sableux, argile calcaire. Le modele prevoit, bien l'influence de la densite seche et permet de calculer pour un sol donne les constantes

  14. Radiobiological researches on Dianthus caryophyllus L. carnation chimeras; Recherches radiobiologiques sur des chimeres d'oeillet Dianthus caryophyllus L.

    Energy Technology Data Exchange (ETDEWEB)

    Pereau-Leroy, Pierre

    1975-04-12

    This research thesis reports a radiobiological study of Dianthus periclinal chimeras performed by submitting plants and plant cuttings at different physiological stages to cobalt-60 gamma irradiation under different dose conditions and rates. The effects of these treatments are studied while growing the so-processed plants and by microscopic examination of sections of irradiated meristems [French] Une etude radiobiologique de chimeres periclinales d'oeillet est effectuee en soumettant au rayonnement gamma du cobalt 60, sous differentes conditions de doses et debits de dose, des plantes entieres et des boutures a des stades physiologiques differents. Les effets des traitements sont observes au cours de la culture des plantes traitees et par l'examen microscopique de coupes des meristemes irradies. La destruction de cellules meristematiques, dans des proportions variables avec les modalites d'irradiation, provoque des modifications de structure des chimeres dont les plus frequentes sont la formation de tiges genetiquement homogenes a partir des differents genotypes existants dans la plante irradiee. Le traitement aux radiations ionisantes constitue donc une methode pratique de detection des chimeres periclinales qui, a l'image de ce qui se passe pour l'oeillet, sont tres repandues chez les plantes cultivees a propagation vegetative. Mais, comme il existe generalement plus de deux ensembles cellulaires meristematiques independants, cette methode ne permet pas, a elle seule, de definir la repartition des differents genotypes dans ces ensembles; elle doit alors etre completee par des etudes genetiques ou des marquages cellulaires tels que des mutations chlorophylliennes ou de genomes. Ainsi la structure de deux varietes d'oeillet a fleurs oranges, qui produisent, apres irradiation, des fleurs rouges et des fleurs jaunes, a ete determinee grace a l'obtention, par traitement a la colchicine, de cytochimeres 4 - 2 - 2 et 2 - 4 - 4. Les tiges a fleurs jaunes, produites par

  15. The surface analysis methods; Les methodes d`analyse des surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Deville, J.P. [Institut de Physique et Chimie, 67 - Strasbourg (France)

    1998-11-01

    Nowadays, there are a lot of surfaces analysis methods, each having its specificity, its qualities, its constraints (for instance vacuum) and its limits. Expensive in time and in investment, these methods have to be used deliberately. This article appeals to non specialists. It gives some elements of choice according to the studied information, the sensitivity, the use constraints or the answer to a precise question. After having recalled the fundamental principles which govern these analysis methods, based on the interaction between radiations (ultraviolet, X) or particles (ions, electrons) with matter, two methods will be more particularly described: the Auger electron spectroscopy (AES) and x-rays photoemission spectroscopy (ESCA or XPS). Indeed, they are the most widespread methods in laboratories, the easier for use and probably the most productive for the analysis of surface of industrial materials or samples submitted to treatments in aggressive media. (O.M.) 11 refs.

  16. Discontinuous finite element and characteristics methods for neutrons transport equation solution in heterogeneous grids; Resolution de l'equation du transport des neutrons par les methodes des elements finis discontinus et des caracteristiques structurees appliquees a des maillages heterogenes

    Energy Technology Data Exchange (ETDEWEB)

    Masiello, E

    2006-07-01

    The principal goal of this manuscript is devoted to the investigation of a new type of heterogeneous mesh adapted to the shape of the fuel pins (fuel-clad-moderator). The new heterogeneous mesh guarantees the spatial modelling of the pin-cell with a minimum of regions. Two methods are investigated for the spatial discretization of the transport equation: the discontinuous finite element method and the method of characteristics for structured cells. These methods together with the new representation of the pin-cell result in an appreciable reduction of calculation points. They allow an exact modelling of the fuel pin-cell without spatial homogenization. A new synthetic acceleration technique based on an angular multigrid is also presented for the speed up of the inner iterations. These methods are good candidates for transport calculations for a nuclear reactor core. A second objective of this work is the application of method of characteristics for non-structured geometries to the study of double heterogeneity problem. The letters is characterized by fuel material with a stochastic dispersion of heterogeneous grains, and until now was solved with a model based on collision probabilities. We propose a new statistical model based on renewal-Markovian theory, which makes possible to take into account the stochastic nature of the problem and to avoid the approximations of the collision probability model. The numerical solution of this model is guaranteed by the method of characteristics. (author)

  17. Discontinuous finite element and characteristics methods for neutrons transport equation solution in heterogeneous grids; Resolution de l'equation du transport des neutrons par les methodes des elements finis discontinus et des caracteristiques structurees appliquees a des maillages heterogenes

    Energy Technology Data Exchange (ETDEWEB)

    Masiello, E

    2006-07-01

    The principal goal of this manuscript is devoted to the investigation of a new type of heterogeneous mesh adapted to the shape of the fuel pins (fuel-clad-moderator). The new heterogeneous mesh guarantees the spatial modelling of the pin-cell with a minimum of regions. Two methods are investigated for the spatial discretization of the transport equation: the discontinuous finite element method and the method of characteristics for structured cells. These methods together with the new representation of the pin-cell result in an appreciable reduction of calculation points. They allow an exact modelling of the fuel pin-cell without spatial homogenization. A new synthetic acceleration technique based on an angular multigrid is also presented for the speed up of the inner iterations. These methods are good candidates for transport calculations for a nuclear reactor core. A second objective of this work is the application of method of characteristics for non-structured geometries to the study of double heterogeneity problem. The letters is characterized by fuel material with a stochastic dispersion of heterogeneous grains, and until now was solved with a model based on collision probabilities. We propose a new statistical model based on renewal-Markovian theory, which makes possible to take into account the stochastic nature of the problem and to avoid the approximations of the collision probability model. The numerical solution of this model is guaranteed by the method of characteristics. (author)

  18. Direct determination of enthalpies of solid phase reactions by immersion method; Determination directe des enthalpies de reaction en phase solide par une methode de plongee

    Energy Technology Data Exchange (ETDEWEB)

    Roux, A; Richard, M; Eyraud, L; Stevanovic, M; Elston, J [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1967-07-01

    It is not generally possible to measure the enthalpy change corresponding to solid phase reactions using the dynamic differential thermal analysis method because these reactions are usually too slow at the temperature of operation of present equipment. A ballistic differential thermal analysis apparatus has been developed which is based on an immersion-compensation method; it overcomes the difficulties previously encountered. This apparatus has been used after calibration for determining the enthalpies of formation of calcium and cadmium titanates. and also the Wigner energies of BeO, MgO and Al{sub 2}O{sub 3} samples irradiated at variable dose at a temperature of under 100 deg. C. (authors) [French] Il n'est generalement pas possible de mesurer la variation d'enthalpie correspondant aux reactions en phase solide par la methode d'analyse thermique differentielle dynamique. En effet, ces reactions sont le plus souvent trop lentes aux temperatures d'utilisation des dispositifs actuels. Un appareil d'analyse thermique differentielle balistique, base sur une methode de plongee avec compensation, a ete mis au point et permet de surmonter les difficultes precedentes. Apres etalonnages, cet appareil a ete utilise pour la determination des enthalpies de formation du titanate de calcium et du titanate de cadmium ainsi que pour celle des energies Wigner emmagasinees dans des echantillons de BeO, MgO et Al{sub 2}O{sub 3} irradies a une temperature inferieure a 100 deg. C et a differentes doses. (auteurs)

  19. Implementation en VHDl/FPGA d'afficheur video numerique (AVN) pour des applications aerospatiales

    Science.gov (United States)

    Pelletier, Sebastien

    L'objectif de ce projet est de developper un controleur video en langage VHDL afin de remplacer la composante specialisee presentement utilisee chez CMC Electronique. Une recherche approfondie des tendances et de ce qui se fait actuellement dans le domaine des controleurs video est effectuee afin de definir les specifications du systeme. Les techniques d'entreposage et d'affichage des images sont expliquees afin de mener ce projet a terme. Le nouveau controleur est developpe sur une plateforme electronique possedant un FPGA, un port VGA et de la memoire pour emmagasiner les donnees. Il est programmable et prend peu d'espace dans un FPGA, ce qui lui permet de s'inserer dans n'importe quelle nouvelle technologie de masse a faible cout. Il s'adapte rapidement a toutes les resolutions d'affichage puisqu'il est modulaire et configurable. A court terme, ce projet permettra un controle ameliore des specifications et des normes de qualite liees aux contraintes de l'avionique.

  20. Biological Dosimetry Methods Employed at the Boris Kidric Institute of Nuclear Sciences; Application de Quelques Methodes Particulieres de Dosimetrie Biologique a l'Institut des Sciences Nucleaires Boris Kidric

    Energy Technology Data Exchange (ETDEWEB)

    Aleksic, B.; Veljkovic, D.; Djordjevic, O.; Djukic, Z. [Institut des Sciences Nucleaires Boris Kidric, Belgrade, Yugoslavia (Serbia)

    1971-06-15

    In addition to the more usual methods, the following methods are used at the Boris Kidric Institute of Nuclear Sciences in the medical supervision of occupationally exposed staff: analysis of bi nucleated lymphocytes and chromosome aberrations; physical examination (for example, determination of the pain sensitivity threshold, adaptation to pain, discrimination of sensitivity); capillaroscopy. These methods are described briefly and their practical application discussed. (author) [French] Outre les methodes habituelles, on a utilise a l'Institut Boris Kidric, pour le controle medical des travailleurs professionnellement exposes, des methodes d'analyse des lymphocytes binuclees et des aberrations chromosomiques, ainsi que des methodes d'examen physique telles que la determination du seuil de sensibilite douloureuse, de l'adaptation a la douleur et de la discrimination de la sensibilite, et la capillaroscopie. Ces methodes sont brievement decrites et leurs applications pratiques discutees. (author)

  1. Amount and activity of fission products which will be obtainable in France in the immediate future taking into account the development of atomic energy; Quantite et activite des produits de fission abtenus en France dans les annees a venir compte tenu du developpement de l'energie atomique

    Energy Technology Data Exchange (ETDEWEB)

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

    1960-07-01

    By using the Wigner and Way formula, the activity of the complex mixture of fission products produced in a pile may be estimated theoretically in advance. This study was carried out on the basis of forecasts, in the case of France for the production of electricity of atomic origin up to the year 1975. The uranium was assumed to be in the pile during periods of three months and six months. It is also possible to find the activity of a particular fission product and to give its decay rate. The element chosen is strontium for a three months' activation period. Each set of curves gives at any moment the total activity accumulated, and the characteristic activity of the fission products corresponding to a given half-life. (author) [French] En utilisant la formule de Wigner et Way, il est possible de prevoir theoriquement l'activite du melange complexe de produits de fission provenant d'une pile. L'etude a ete faite en tenant compte de previsions, en ce qui concerne la France, de la production d'electricite d'origine atomique jusqu'en 1975. On a suppose des temps de sejour en pile de l'uranium de trois mois et de six mois. Il est possible egalement de trouver l'activite d'un produit de fission particulier, et de donner sa decroissance. Le corps choisi est le strontium pour un temps d'activation de trois mois. Chaque ensemble de courbes donne a tout instant l'activite totale accumulee, et l'activite propre des produits de fission correspondant a une periode donnee. (auteur)

  2. Detection de la fin de la compaction des anodes par le son

    Science.gov (United States)

    Sanogo, Bazoumana

    L'objectif de ce projet etait de developper un outil de controle en temps reel du temps de compaction en se servant du son genere par le vibrocompacteur pendant le formage des anodes crues. Ainsi, une application a ete developpee pour l'analyse des sons enregistres. Des essais ont ete realises avec differents microphones pour une meilleure qualite des mesures et un a ete choisi pour la suite du projet. De meme, differents tests ont ete realises sur des anodes de laboratoire ainsi que des anodes a l'echelle industrielle afin de mettre en place une methode pour la detection du temps optimal necessaire au formage des anodes. Les travaux au laboratoire de carbone a l'Universite du Quebec a Chicoutimi (UQAC) ont consiste a l'enregistrement de son des anodes fabriquees sur place avec differentes configurations; et a la caracterisation de certaines anodes de l'usine. Les anodes fabriquees au laboratoire sont reparties en deux groupes. Le premier regroupe les anodes pour la validation de notre methode. Ce sont des anodes produites avec des temps de compaction differents. Le laboratoire de carbone a l'UQAC est unique et il est possible de produire des anodes avec les memes proprietes que celles des anodes industrielles. Par consequent, la validation initialement prevue a l'usine a ete effectuee avec les anodes de laboratoire. Le deuxieme groupe a servi a etudier les effets des matieres premieres sur le temps de compaction. Le type de coke et le type de brai ont constitue les differentes variations dans ce deuxieme groupe. Quant aux tests et mesures a l'usine, ils ont ete realises en trois campagnes de mesure. La premiere campagne en juin 2014 a servi a standardiser et a trouver le meilleur positionnement des appareils pour les mesures, a regler le logiciel et a faire les premieres mesures. Une deuxieme campagne en mai 2015 a fait l'objet d'enregistrement de son en classant les anodes selon differents temps de compaction. La troisieme et derniere campagne en decembre 2015 a

  3. Hartree-Fock theory for the equilibrium shape of light nuclei; Theorie Hartree-Fock de la forme d'equilibre des noyaux legers

    Energy Technology Data Exchange (ETDEWEB)

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

    1968-09-01

    Most of the content of this thesis is published in english in Advances In Nuclear Physics, Vol. 1 (Editors: Baranger and Vogt - Plenum Press). The Hartree- Fock equations are derived. The expansions of the orbits and the possible symmetries of the Hartree-Fock field are discussed. Wavefunctions of even-even N = Z nuclei are given for 12 {<=} A {<=} 40. The role of the monopole, quadrupole and exchange components of the force are discussed. The multiplicity of the solutions and the effect of the spin-orbit interaction are discussed. Exact angular momentum projection is used to generate rotational bands. The validity of the adiabatic rotational model in light nuclei is discussed. Hartree-Fock calculations are extended to include major-shell mixing in order to obtain quadrupole deformations without the use of effective charge. The incompressibility, of nuclei is discussed and the compatibility between the Hartree-Fock solutions, the Mottelson model of quadrupole deformations and the SU3 states of J.P. Elliott and M. Moshinsky is established. (author) [French] La theorie de Hartree-Fock est appliquee au calcul des fonctions d'onde des noyaux legers deformes. Les equations de Hartree-Fock, les symetries permises et le choix du developpement des orbites sont discutes. Les fonctions d'onde des noyaux pair-pairs N = Z (12 {<=} A {<=} 40) sont tabulees. Les contributions des composantes monopolaires et quadrupolaires ainsi que des termes d'echange de la force nucleon-nucleon sont discutees. La methode de projection de moment cinetique est utilisee pour engendrer les bandes de rotation. La validite du modele rotationnel adiabatique est discutee. Les calculs de Hartree-Fock qui tiennent compte du melange de plusieurs couches majeures dans chaque orbite sont appliques au calcul des deformations quadrupolaires sans l'utilisation de charge effective. L'incompressibilite des noyaux et la compatibilite des fonctions d'onde de Hartree- Fock avec les fonctions d'onde SU3 de J

  4. Hartree-Fock theory for the equilibrium shape of light nuclei; Theorie Hartree-Fock de la forme d'equilibre des noyaux legers

    Energy Technology Data Exchange (ETDEWEB)

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

    1968-09-01

    Most of the content of this thesis is published in english in Advances In Nuclear Physics, Vol. 1 (Editors: Baranger and Vogt - Plenum Press). The Hartree- Fock equations are derived. The expansions of the orbits and the possible symmetries of the Hartree-Fock field are discussed. Wavefunctions of even-even N = Z nuclei are given for 12 {<=} A {<=} 40. The role of the monopole, quadrupole and exchange components of the force are discussed. The multiplicity of the solutions and the effect of the spin-orbit interaction are discussed. Exact angular momentum projection is used to generate rotational bands. The validity of the adiabatic rotational model in light nuclei is discussed. Hartree-Fock calculations are extended to include major-shell mixing in order to obtain quadrupole deformations without the use of effective charge. The incompressibility, of nuclei is discussed and the compatibility between the Hartree-Fock solutions, the Mottelson model of quadrupole deformations and the SU3 states of J.P. Elliott and M. Moshinsky is established. (author) [French] La theorie de Hartree-Fock est appliquee au calcul des fonctions d'onde des noyaux legers deformes. Les equations de Hartree-Fock, les symetries permises et le choix du developpement des orbites sont discutes. Les fonctions d'onde des noyaux pair-pairs N = Z (12 {<=} A {<=} 40) sont tabulees. Les contributions des composantes monopolaires et quadrupolaires ainsi que des termes d'echange de la force nucleon-nucleon sont discutees. La methode de projection de moment cinetique est utilisee pour engendrer les bandes de rotation. La validite du modele rotationnel adiabatique est discutee. Les calculs de Hartree-Fock qui tiennent compte du melange de plusieurs couches majeures dans chaque orbite sont appliques au calcul des deformations quadrupolaires sans l'utilisation de charge effective. L'incompressibilite des noyaux et la compatibilite des fonctions d'onde de Hartree- Fock avec les

  5. Some examples of the use of radioactive tracers in pharmacodynamic; Quelques exemples de l'emploi des traceurs radioactifs en pharmacodynamie

    Energy Technology Data Exchange (ETDEWEB)

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

    1960-07-01

    The study of absorption, of distribution in the organism and of the elimination of a medicament has been greatly facilitated by the development of nuclear applications. In effect, the introduction into the molecule of one or several radioactive atoms makes it possible to follow the path and destination of minute quantities of the drug and to thus carry out analyses on the animal within limits of posology close to those of therapeutics. However the qualitative or quantitative methods used have certain limits and they must be compared amongst themselves and with others. Some examples will show : - the importance of the way of administering the drug on the changes in the distribution; - the quite relative selectivity of this latter; - and lastly, the different process involved in the elimination mechanisms. (author) [French] L'etude de l'absorption, de la repartition dans l'organisme et de l'elimination d'un medicament s'est trouvee grandement facilitee par le developpement des applications nucleaires. En effet, l'introduction dans une molecule d'un ou plusieurs atomes radioactifs permet de suivre le sort de quantites infimes de la drogue et de ce fait d'en effectuer l'analyse chez l'animal dans des limites de posologie se rapprochant de celles de la therapeutique. Cependant les methodes employees, qualitatives ou quantitatives, presentent des limites et doivent etre confrontees entre elles et avec d'autres methodes. Quelques exemples mettront en evidence: - l'importance du mode d'administration sur l'evolution de la repartition, - l'electivite toute relative de cette derniere, - et enfin, les modalites diverses des mecanismes d'elimination. (auteur)

  6. Nouvelle methode d'integration energetique pour la retro-installation des procedes industriels et la transformation des usines papetieres

    Science.gov (United States)

    Bonhivers, Jean-Christophe

    The increase in production of goods over the last decades has led to the need for improving the management of natural resources management and the efficiency of processes. As a consequence, heat integration methods for industry have been developed. These have been successful for the design of new plants: the integration principles are largely employed, and energy intensity has dramatically decreased in many processes. Although progress has also been achieved in integration methods for retrofit, these methods still need further conceptual development. Furthermore, methodological difficulties increase when trying to retrofit heat exchange networks that are closely interrelated to water networks, such as the case of pulp and paper mills. The pulp and paper industry seeks to increase its profitability by reducing production costs and optimizing supply chains. Recent process developments in forestry biorefining give this industry the opportunity for diversification into bio-products, increasing potential profit margins, and at the same time modernizing its energy systems. Identification of energy strategies for a mill in a changing environment, including the possibility of adding a biorefinery process on the industrial site, requires better integration methods for retrofit situations. The objective of this thesis is to develop an energy integration method for the retrofit of industrial systems and the transformation of pulp and paper mills, ant to demonstrate the method in case studies. Energy is conserved and degraded in a process. Heat can be converted into electricity, stored as chemical energy, or rejected to the environment. A systematic analysis of successive degradations of energy between the hot utilities until the environment, through process operations and existing heat exchangers, is essential in order to reduce the heat consumption. In this thesis, the "Bridge Method" for energy integration by heat exchanger network retrofit has been developed. This method

  7. Automatic speech recognition (zero crossing method). Automatic recognition of isolated vowels; Reconnaissance automatique de la parole (methode des passages par zero). Reconnaissance automatique de voyelles isolees

    Energy Technology Data Exchange (ETDEWEB)

    Dupeyrat, Benoit

    1975-06-10

    This note describes a recognition method of isolated vowels, using a preprocessing of the vocal signal. The processing extracts the extrema of the vocal signal and the interval time separating them (Zero crossing distances of the first derivative of the signal). The recognition of vowels uses normalized histograms of the values of these intervals. The program determines a distance between the histogram of the sound to be recognized and histograms models built during a learning phase. The results processed on real time by a minicomputer, are relatively independent of the speaker, the fundamental frequency being not allowed to vary too much (i.e. speakers of the same sex). (author) [French] Cette note decrit une methode de reconnaissance automatique de voyelles isolees basee sur un pretraitement particulier du signal vocal. Ce pretraitement consiste a extraire les extrema du signal vocal et les intervalles de temps les separant (distances entre passages par zero de la derivee du signal). La reconnaissance des voyelles est faite en utilisant des histogrammes normalises des valeurs de ces interval les. Le programme de reconnaissance utilise une distance entre l'histogramme du son a reconnaitre et des histogrammes modeles provenant d'un apprentissage. Les resultats obtenus en temps reels sur un minicalculateur, sont assez independants du locuteur, pourvu que la frequence fondamentale de la voix ne varie pas trop (locuteurs de meme sexe). (auteur)

  8. Count rate balance method of measuring sediment transport of sand beds by radioactive tracers; Methode du bilan des taux de comptage d'indicateurs radioactifs pour la determination du debit de charriage des lits sableux

    Energy Technology Data Exchange (ETDEWEB)

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

    1967-11-01

    Radioactive tracers are applied to the direct measurement of the sediment transport rate of sand beds. The theoretical measurement formula is derived: the variation of the count rate balance is inverse of that of the transport thickness. Simultaneously the representativeness of the tracer is critically studied. The minimum quantity of tracer which has to be injected in order to obtain a correct statistical definition of count rate given by a low number of grains 'seen' by the detector is then studied. A field experiment was made and has let to study the technological conditions for applying this method: only the treatment of results is new, the experiment itself is carried out with conventional techniques applied with great care. (author) [French] Les indicateurs radioactifs sont appliques a la mesure directe du debit de charriage des lits sableux. On etablit la formule theorique de mesure: le bilan des taux de comptage varie en sens inverse de l'epaisseur de charriage. Parallelement on fait une etude critique de la representativite de l'indicateur, puis on determine la quantite minimale de traceur qu'il faut immerger pour que les taux de comptage fournis pour un faible nombre de grains 'vus' par le detecteur aient une definition statistique correcte. Une experience de terrain a permis d'etudier les conditions technologiques de cette methode: seul le depouillement des resultats est nouveau. L'experimentation in-situ se fait suivant les procedes classiques avec un tres grand soin. (auteur)

  9. Automation on computer of the partial area method in the analysis of resonances induced by 'S' neutrons 2. with an interference term and extension of the method to the treatment of multi resonances (1963); Automatisation sur ordinateur de la methode des aires partielles dans l'analyse des resonances induites par les neutrons ''S''. 2, avec terme d'interference et extension de la methode au traitement des multiresonances (1963)

    Energy Technology Data Exchange (ETDEWEB)

    Bianchi, G; Corge, C R [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1963-07-01

    This report deals with the numerical analysis on an I.B.M. 7090 computer of transmission resonances induced by 's' wave neutrons in time of flight experiments. The analysis method used is the partial area one. In this second part the interference term is taken into account. Modifications have been made in the programs and subroutines described in the first part, to determine the resonant transmissions from experimental raw data, and the relating partial areas. Also programs and subroutines are thoroughly described, which estimate the resonance parameters. The field of the partial area method has been extended to cover the case where several resonances have to be treated simultaneously, provided they do not interfere. (authors) [French] Le pretent rapport a pour objet l'analyse numerique sur ordinateur I.B.M. 7090 des resonances dues aux neutrons ''s'' dans les experiences de transmission par temps de vol, la methode d'analyse utilisee etant la methode dea aires partielles. Dans cette deuxieme partie il a ete tenu compte du terme d'interference. On y trouvera une description des amenagements apportes aux programmes et sous-programmes decrits dans la premiere partie pour determiner les transmissions interfero-resonnantes a partir des donnees experimentales brutes et les aires partielles afferentes. Sont egalement decrits les programmes et sous-programmes necessaires au calcul des parametres caracteristiques des resonances. Le domaine d'application de la methode a ete etendu au traitement simultane de plusieurs resonances groupees n'interferant pas entre elles. (auteurs)

  10. Production method of {alpha} particles; Une methode de production des particules {alpha}

    Energy Technology Data Exchange (ETDEWEB)

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

    1953-07-01

    It is proposed a method to get an intense beam of {alpha} particles. With a source of ordinary ions, we form a helium beam, once ionized, it is accelerated with an energy of a few hundreds of keV. While crossing a matter any that can be a thin leaf or a gaseous blade, the second electron of helium is pulled with a yield that only depends on the energy of the beam of helium and that is equal to 1/2 for 650 keV. (author) [French] Il est propose une methode pour obtenir un faisceau intense de particules {alpha}. Avec une source d'ions ordinaire, on forme un faisceau d'helium une fois ionise qu'on accelere avec une energie de quelques centaines de keV. En traversant une matiere quelconque qui peut etre sous forme de feuille mince ou de lame gazeuse, le deuxieme electron de l'helium est arrache avec un rendement qui ne depend que de l'energie du faisceau d'helium et qui vaut 1/2 pour 650 keV. (auteur)

  11. A decision aiding and action management tool to control the energy demand - from conception to development; Un outil d`aide a la decision et de gestion des actions pour la maitrise de la demande d`energie - de la conception au developpement

    Energy Technology Data Exchange (ETDEWEB)

    Kaehler, J W.M.

    1993-07-06

    This work presents a synthesis of three points: the environment, energy and man. The consideration of these aspects allows us to confront the unequal distribution of energy resources, the constraints and political influences which determine the exploitation of these energy resources, and the concentration of the consumption of energy by one fifth of the world`s population and the perspective of future growth of energy use by the remaining four-fifths. It is understanding of the importance and the benefits of reducing energy requirements, combined with the environmental perspectives, that forms the core of the Integrated Resource Planning of Least is proposed. This framework will utilize the knowledge of the engineer for developing a system to aid with decision making and the management of information, and particularly with the notions henceforth referred to as `Demand-Site Management` as applied to the electrical grid. The model of such a Management Information System which demonstrates these theoretical advances is called SIADEME (Systeme Interactif d`Aide a la Decision et de Gestion des Actions de Maitrise de la Demande d`energie). This includes some examples for the management of electricity demand for both the lighting and refrigeration cases in large (> 2500 m{sup 2}) supermarkets for the French environmental and energy management agency (Ademe). (author) 216 refs.

  12. The Application of Various Nondestructive Testing Methods to Fuel Elements of the Orgel Type; Application des Differentes Methodes d'Essais Non Destructifs aux Elements Combustibles du Type Orgel; Primenenie razlichnykh nedestruktivnykh metodov ispytanij k toplivnym ehlementam tipa ''orgel''; Aplicacion de Distintos Metodos de Ensayo No Destructivo a los Elementos Combustibles de Tipo Orgel

    Energy Technology Data Exchange (ETDEWEB)

    Bonnet, P.; Jansen, J. [EURATOM, C.C.R., Ispra (Italy)

    1965-09-15

    methode a un capteur montre quelles sont les limites d'utilisation de ces deux methodes. Defauts transversaux; La methode a un capteur appliquee a cette recherche fait l'objet d'une breve description. Entrainement mecanique: Le memoire fait etat d'un banc mecanique, type laboratoire, pour la recherche des criteres d'essais et d'un banc de passage des tubes, de type semi-industriel, pour l'examen en continu avec enregistrement des defauts. Les difficultes rencontrees et les moyens misenceuvrepoury remediersont evoques. c) Tests par radiographie. Cette methode fera l'objet d'un memoire special; seuls sont indiques les resultats obtenus sur tubes de force ou sur tubes de gaines. d) Test divers Les test finaux sur elements combustibles complets peuvent se resumer en deux parties. Tests d'etancheite au moyen du test a l'helium developpe par la SOGEV. Un dispositif permet d'examiner simultanement 4 ou 6 elements combustibles ou separement 2 ou 3. Tests classiques de radiographie; l'accent est mis plus particulierement sur l'etude des soudures; on donne la marge des conditions experimentales pour obtenir une bonne definition. En conclusion, les auteurs presentent un projet de chaine de controle semi-industrielle avec les differentes possibilites de traitements et essaient de degager une certaine philosophie des tests non destructifs appliques aux elements combustibles. (author) [Spanish] La memoria presenta los distintos metodos empleados para deteccion de fallas (de tipo dimensional o estructural) en vainas de elementos combustibles. Los autores describen, asimismo, los ensayos finales con elementos combustibles completos, en particular radiografia de las soldaduras y pruebas de estanqueidad. Este tema se ha tratado ya en forma parcial. El estudio de las caracteristicas dimensionales de las vainas lisas de SAP (producto de aluminio sinterizado) ha sido objeto de trabajos bastante avanzados. La memoria examina en particular los siguientes temas: 1. Medicion de diametros internos

  13. Application of the geophysical and geochemical methods to the research for uranium; Application a la recherche de l'uranium des methodes geophysiques et geochimiques

    Energy Technology Data Exchange (ETDEWEB)

    Gangloff, A M; Collin, C R; Grimbert, A; Sanselme, H [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1958-07-01

    Since 1954, at the Commissariat a l'energie atomique, geophysics and geochemistry have been added to routine geological surveying and radiometric observations. Geophysical prospecting reveals the tectonic structures linked with French uranium deposits and gives an idea of favorable zones. Geochemistry adds to the geophysical indirect methods further details on the distribution of uranium traces in the soils. This method is direct and specific. Uranium assay in waters and alluvial deposits find its use in preliminary exploration. (author) [French] Depuis 1954, au CEA, a l'observation geologique directe et aux mesures radiometriques, sont venues s'ajouter des methodes relevant de la geophysique et de la geochimie. La prospection geophysique apporte des precisions sur les structures tectoniques auxquelles sont lies les gisements d'uranium fran is et sur la notion de zones favorables. Aux methodes indirectes de la geophysique, la prospection geochimique ajoute des precisions sur la repartition de l'uranium en traces dans les sols, cette methode est directe et specifique. Le dosage de l'uranium dans les eaux et les alluvions trouve son application dans la prospection de reconnaissance. (auteur)

  14. Contribution to the experimental study of excited levels of some light nuclei by using the method of angular correlation of internal conversion pairs and monopolar pairs; Contribution a l'etude experimentale de niveaux excites de quelques noyaux legers par la methode des Correlations angulaires des paires de conversion interne Et des paires monopolaires

    Energy Technology Data Exchange (ETDEWEB)

    Armbruster, Raymond

    1950-07-01

    In a first part, the author presents a brief theory of angular correlations of internal conversion pairs and monopolar pairs, and indicates the complete formulations which are used to compute all the angular correlations corresponding to the performed experiments. In a second part, he describes a beta spectrometer, outlines factors which govern the energy resolving power, and the peculiarity of summation of two pulses proportional to the energy of the electron and positron which build up an internal pair. In a third part, the author reports experiments of angular correlations, indicates the shapes of monopolar spectra for different angles between electron and positron emission directions, determines the multipolarity of gamma radiations from the first excited levels of {sup 13}C and {sup 12}C, and gives the angular moments, parity and isobaric spin of two excited levels of the {sup 12}C [French] Dans la premiere partie de notre travail, nous exposons une theorie sommaire des correlations angulaires des paires de conversion interne et des paires monopolaires. A la fin de cette premiere partie sont indiquees les formules completes, qui nous ont servi a calculer pratiquement toutes les correlations angulaires correspondant a nos experiences. Dans la deuxieme partie, nous decrivons un spectrometre beta a scintillation. Nous insistons surtout sur les elements qui determinent le pouvoir de resolution en energie et sur la particularite de sommation de deux impulsions proportionnelles a l'energie de l'electron et du positron formant une paire interne. Dans la troisieme partie, nous exposons nos experiences de correlations angulaires. Nous avons repris une mesure precise de la correlation angulaire des paires monopolaires provenant du niveau 6,05 Mev de l'Oxygene 16. Il nous a ete egalement possible de donner l'allure des spectres monopolaires pour differents angles formes par les directions d'emission de l'electron et du positron. Nous avons determine par la methode des

  15. Developpement d'une methode d'analyse du cycle de vie consequentielle prospective macroscopique : Evaluation d'une politique de bioenergie dans L'Union Europeenne a l'horizon 2025

    Science.gov (United States)

    Dandres, Thomas

    Most of the time, the increase in human activities harms the environment. Due to the capacity limit of the Earth to bear such impacts and considering the growth of world population and its demands, there is a need to manage the future growth of human society in order to mitigate its impacts on the environment. Life cycle assessment (LCA) seems to be a great methodology for this purpose because it assesses different types of environmental impacts of a product or service based on all of its life cycle stages. However, it appears that LCA is not adapted to the evaluation of large-scale international policies required for some environmental issues. Especially, current LCA methodology fails to properly model indirect consequences on the environment of a major change within the energy sector in order to reduce greenhouse gas emissions and mitigate climate change. To model these indirect consequences on the environment, global economy modeling is required as a major change in the energy sector is expected to affect the rest of the economy and therefore to cause indirect environmental impacts. This is the goal of this university thesis: Develop a new decision tool "macroscopic life cycle assessment" using the LCA methodology and the GTAP macroeconomic model in order to assess environmental impacts caused by significant changes in human society. Application of macroscopic LCA to two different European energy policies for the 2005-2025 period shows its ability to model some rebound effects and to compare environmental benefits obtained from a bioenergy policy versus environmental impacts caused by the economic growth during 2005-2025. Additionally, the method allows to identify regions where and time periods when environmental impacts are expected to occur. Macroscopic LCA has important application opportunities for LCA: while the methodology is usually used to study the environmental profile of a product or service, it now becomes possible to evaluate environmental

  16. Graphite reactor physics; Physique des piles a graphite

    Energy Technology Data Exchange (ETDEWEB)

    Bacher, P; Cogne, F [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires; Noc, B [Electricite de France (EDF), 75 - Paris (France)

    1964-07-01

    physique des piles de puissance a graphite et uranium naturel se poursuit depuis parallelement au developpement de ce type de piles. L'etude systematique des proprietes des reseaux en fonction du pas, de la geometrie du combustible et du diametre des canaux de refroidissement a pu etre entreprise a partir de 1960 grace a l'empilement critique MARIUS. Cette etude a permis de couvrir un domaine tres etendu: pas variant de 19 a 38 cm, barreaux et tubes d'uranium dont les sections droites vont de 6 a 35 cm{sup 2}, canaux dont le diametre est compris entre 70 et 140 mm. On a pu ainsi verifier, et au besoin adapter, les methodes de calcul de reseaux. Le fonctionnement des piles de Marcoule, ainsi que les experiences effectuees sur ces piles au cours des dernieres annees, ont apporte des renseignements precieux sur l'evolution globale des proprietes neutroniques du combustible en fonction de l'irradiation. Des experiences plus precises ont egalement ete faites dans MARIUS avec des combustibles contenant du plutonium (combustibles irradiee ou reconstitues), et seront entreprises des le debut 1965 en temperature dans l'empilement critique CESAR, dont la construction s'acheve a Cadarache. Les analyses des combustibles irradies permettent de completer ces resultats et de faciliter leur interpretation. Il sera ainsi possible de verifier dans tout le domaine utile de temperature les theories de thermalisation et de spectres developpees en France. L'efficacite de barres de controle en fonction de leurs dimensions, des materiaux les constituant, et des reseaux les environnant a ete mesuree dans MARIUS, et les resultats ont ete confrontes d'une part avec le calcul, d'autre part avec les mesures effectuees dans EDF 1. Les etudes du controle proprement dit des piles a graphite ont porte essentiellement sur les risques d'instabilites spatiales, et sur les moyens de les deceler et de les combattre, ainsi que sur les deformations du flux provoquees par les barres de controle. (auteurs)

  17. 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

  18. Preliminary studies of the kinetics of a reactor by the probability method; Etude preliminaire de la cinetique d'un reacteur par la methode des probabilites

    Energy Technology Data Exchange (ETDEWEB)

    Bruna, J G; Brunet, J P; Clouet D' Orval, Ch; Caizergues, R; Verriere, Ph [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1964-07-01

    The {alpha} decay constant of prompt neutrons has been studied in the homogeneous plutonium-fueled, light-water-moderated reactor Alecto, by the probability method. In this method, the probability to count one, two,.... neutrons during a given time is measured. The value of {alpha} can be deduced from this measurement, for various subcritical states of the reactor. The experimental results were then compared with values obtained, for the same reactivities, by the pulsed neutron technique. (authors) [French] On a etudie sur Alecto, reacteur homogene au plutonium, modere a l'eau legere, la constante de decroissance {alpha} des neutrons prompts par la methode des probabilites. Celle-ci consiste a mesurer la probabilite de compter un, deux, etc..., neutrons pendant un intervalle de temps donne. On a pu en deduire la valeur de {alpha}, dans divers etats sous-critiques du reacteur. On a compare les resultats experimentaux a d'autres valeurs obtenues, aux memes reactivites, par la methode des neutrons pulses. (auteurs)

  19. Arthropathie destructrice des epaules au cours d�une acromegalie

    Directory of Open Access Journals (Sweden)

    Nessrine Akasbi

    2011-10-01

    Full Text Available L�acromegalie est une maladie endocrinienne rare, en rapport avec une hypersecretion d�hormone de croissance. Elle a des consequences rhumatologiques: l�arthropathie peripherique, l�atteinte rachidienne et les syndromes canalaires. L�atteinte articulaire accompagne une acromegalie active, sa survenue apres un traitement radical et une remission complete est rare. Nous presentons le cas d�une patiente de 70 ans ayant un antecedent d�acromegalie sur adenome hypophysaire il y a 25 ans, traitee chirurgicalement et declaree en remission complete, a developpe une arthropathie destructrice des deux epaules. Le but de notre observation est de mettre le point sur la possibilite d�une atteinte articulaire au cours de l�acromegalie et de son retentissement fonctionnelle.

  20. 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

  1. 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

  2. Risk analysis related to dangerous materials transport and storage in urban areas; L'integration du risque lie au transport et au stockage des produits chimiques dans la planification urbaine: l'apport des outils d'analyse decisionnelle

    Energy Technology Data Exchange (ETDEWEB)

    Lombard, J; Hubert, P; Pages, P

    1989-12-01

    determiner sur des bases objectives quel moyen retenir. Cette etape n'est pas pour autant suffisante, car l'integration des resultats dans les processus decisionnels reste a organiser. L'objet de ce rapport est de presenter differentes methodes d'aide a la decision utilisables a ce jour, en soulignant les criteres sur lesquels elles fondent leur comparaison et leurs limitations dans le contexte envisage ici. Quoique ce point necessite une analyse plus approfondie, quelques rappels generaux des principales particularites de la gestion des risques en milieu urbain (implication possible de multiples acteurs dans la prise de decision et/ou de differents criteres de choix; difficulte d'evaluation des impacts) sont effectues. Les principales methodes d'aide a la decision sont ensuite presentees. Ces methodes se fondent sur un critere unique (respect d'une contrainte reglementaire), sur quelques criteres monetarisables (cout-benefice) ou sur de multiples criteres de choix (fonctions d'utilite). Ces methodes assez generales doivent faire l'objet d'adaptations speifiques pour pouvoir etre appliquees au mieux a un domaine particulier. Pour ce qui concerne la gestion des risques accidentels, les adaptations suivantes sont presentees de maniere critique : - Notion de limite de risque maximal individuel (generalisation d'une contrainte reglementaire). - Adoption de differentes valeurs de la vie humaine en fonction de la nature des consequences de l'accident (generalisation de la methode cout-benefice). - Utilisation de facteurs d'aversion pour le risque (application de la theorie de l'utilite pour prendre en compte le poids important accorde aux evenements catastrophiques). Ces differents developpements visent a proposer des versions des outils d'analyse decisionnelle qui s'appliquent efficacement a la gestion du risque en milieu urbain. (author)

  3. 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

  4. 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

  5. Radioisotopes in sedimentology; Emploi des radioelements en sedimentologie

    Energy Technology Data Exchange (ETDEWEB)

    Courtois, G [CEA, Centre d' etudes Nucleaires de Saclay (France)

    1967-05-15

    infirmation de theses de transport, recherches des phenomenes fondamentaux de transport associees a des experiences en canaux. Apres avoir evoque les possibilites des traceurs naturels, ou dus a des retombees radioactives ou a des rejets d'effluents radioactifs, l'auteur aborde les aspects techniques de l'utilisation des traceurs artificiels: le choix du radioisotope, le marquage superficiel et massique avec mention particuliere du probleme des vases, les appareils d'immersion et de detection, les problemes de navigation et de reperage topographique . Dans la partie concernant l'exploitation des resultats, le probleme de l'obtention de resultats quantitatifs est traite et les methodes proposees decrites; l'auteur fait egalement etat des tentatives actuelles tres louables en vue de relier les tres nombreuses theories de transport de sediments aux parametres mesures sur le terrain au moyen de traceurs radioactifs. Il developpe egalement quelques aspects lies aux problemes de securite. Les methodes decrites peuvent etre egalement appliquees a des problemes voisins et fort interessants: les problemes d'erosion des sols, de stabilisation des terrains, de deplacement des dunes. Quelques indications succinctes sont donnees sur ce sujet. En conclusion, l'auteur indique aussi clairement que possible le potentiel actuel de la methode, ses limitations et les travaux souhaitables pour I'ameliorer. -Mesures en continu de la turbidite. Le transport solide en suspension etant en general beaucoup plus important que le charriage de fond, il importe de pouvoir le mesurer de facon continue; l'auteur donne quelques exemples de l'utilite d'un tel renseignement. Une telle mesure peut etre faite par des jauges decrites dans les ouvrages publies et dont on donne les principes et performances en fonction de la bibliographie connue. L'auteur donne egalement les resultats susceptibles d'etre obtenus en mesurant la turbidite par la radioactivite naturelle d'un sediment en suspension et compare les deux

  6. Mixed approach (numerical modeling / equilibrium analysis) for slope stability analysis: development and application to the dams and open pit mining; Une approche mixte (numerique/equilibre limite) pour le calcul de stabilite des ouvrages en terre: developpement et application aux barrages et talus miniers

    Energy Technology Data Exchange (ETDEWEB)

    Kourdey, A.

    2002-09-15

    The determination of the sliding surface of slope (dam, slope natural..) is one of the important and complicated problems in geotechnics. The Analyze of stability by the methods of Limit Equilibrium like the method of slices are the most used methods. They are able to determine a safety factor for a geometrically defined failure surface. These methods well adapted to the homogeneous mediums, have been developed a lot but they do not integrate the basic relations of mechanics (stress-strain). The numerical methods are better adapted to mediums having more complexity (effect of water, seismicity, fracturing,..). But, they are seldom used to determine a sliding surface and a safety factor. Each family offers appreciable advantages in the analysis of slope stability. For that purpose, we have developed a method that combines the advantages of the numerical methods as well as those of Limit Equilibrium allowing obtaining a slip surface determined by the calculated constraints. This slip surface may be imposed or better optimized, thus providing a minimal safety factor. Methods of operation research are used to obtain this surface. They are search methods by level, dynamic research.. or both at the same time. We integrated these developments in an existing computer code based on the method of Finite Differences known as FLAC. The stresses are determined for a linear behavior and for nonlinear. Interfaces and graphic tools are also produced to facilitate the analysis of stability. The validity of this approach was carried out for a standard case of slope, we analyzed and compared the results with the methods of Limit Equilibrium. The parametric study shows that this approach takes account of different parameters, which influences stability. We also kept a particular place for the application on real cases presenting slopes of different nature (dams, mining slops,...). (author)

  7. Methodes non perturbatives en mecanique quantique et en theorie des champs quantiques

    Science.gov (United States)

    Jirari, Hamza

    2001-10-01

    Nous construisons un hamiltonien effectif à partir de l'intégrale de chemin via la méthode Monte-Carlo. Cet hamiltonien décrit les phénomènes physiques dans le domaine de basse énergie. Nous déterminons le spectre d'énergie et les fonctions d'ondes de plusieurs systèmes quantiques. Les résultats obtenus montrent que cette nouvelle approche Monte-Carlo hamiltonienne fonctionne. En mécanique quantique, nous suggérons une expression analytique de l'intégrale de chemin en introduisant une action quantique avec des paramètres renormalisés. Nous présentons des résultats numériques pour quelques potentiels locaux. Cette action quantique offre la possibilité de comparer l'évolution classique et quantique et permet de quantifier les instantons classiques et éventuellement le chaos classique. Nous investiguons la QCD sur un réseau bidimensionnel en utilisant une version améliorée des fermions de Wilson. Nous montrons que la théorie améliorée conduit à une réduction significative des erreurs dues à la valeur finie du pas du réseau. Nous calculons le condensat chiral et la masse de l'état lié quark-antiquark. Nous aboutissons à une bonne concordance entre nos résultats numériques et les résultats analytiques du modèle dans le continu.

  8. Functional proteomic of Matrix Metallo-proteinases (MMP) dedicated to the detection of active forms of MMP in complex proteome; Proteomique fonctionnelle dediee aux Metalloproteases Matricelles (MMPs): developpement d'une methode extremement sensible permettant la detection des formes actives des MMPs dans des proteomes complexes

    Energy Technology Data Exchange (ETDEWEB)

    David, A

    2007-07-15

    The Matrix Metallo-proteinases (M.M.P.) represent a family of Zinc dependent extracellular proteinases able to cleave collectively all the proteins constituting the extracellular matrix. Currently, 23 human M.M.P. have been identified and are characterized by their sequence in amino-acids and their highly conserved 3 D structure. These enzymes are expressed constitutively during the tissue remodeling process. Their over-expression in various diseases tightly related to inflammatory processes (arthritis, emphysema, cancer) described M.M.P. as choice therapeutic targets. However, as the tissue remodeling implicates modification of cellular contacts, M.M.P. appear currently as proteins involved in signalling pathways. Recent works demonstrating that M.M.P. are able to cleave substrates, which are different than proteins constituting the extracellular matrix, reinforce this vision. In order to identify the individual role and the protein expression level of M.M.P. in pathological context, we developed a new technique of functional proteomics dedicated to the detection of active forms of M.M.P. in tumour samples. This technique relied on the development of a new photoaffinity probe, based on the structure of a potent phosphinic inhibitor of M.M.P., allowing targeting and isolating active forms of M.M.P. by photoaffinity labelling. Furthermore, as the new developed probe incorporated a radioactive element, photoaffinity labelling permitted to radiolabel the targeted proteins. This probe demonstrated in vitro its remarkable ability to covalently modify the h M.M.P.-12, with a singular cross-linking yield, determined at 42 %, displaying an extremely sensitive detection (2.5 fmoles of h M.M.P.-12). When added to complex proteome, the photoaffinity probe presents the same sensibility of detection for the h M.M.P.-12 (5 fmoles); importantly, in this case, h M.M.P.-12 represents only 0.001 % of the totality of the proteins present in the sample. Moreover, this technique allows us to identify active forms of gelatinases (M.M.P.-2 and -9) in an indirect manner by comparing the results of tumour samples treated with the photoaffinity probe and the results of tumour samples analysed in zymography. These studies indicate that the protein expression levels of active forms of M.M.P. are extremely low (fmoles) and do not permit any characterisation of those forms of M.M.P. by mass spectrometry, constituting a genuine challenge which can be approached by the development of new photoaffinity probes incorporating a biotin-group. The example of this class of proteins expressed in very low abundance under active form implicates to grant efforts to develop new strategies allowing the capture of the targeted proteins. (author)

  9. Functional proteomic of Matrix Metallo-proteinases (MMP) dedicated to the detection of active forms of MMP in complex proteome; Proteomique fonctionnelle dediee aux Metalloproteases Matricelles (MMPs): developpement d'une methode extremement sensible permettant la detection des formes actives des MMPs dans des proteomes complexes

    Energy Technology Data Exchange (ETDEWEB)

    David, A

    2007-07-15

    The Matrix Metallo-proteinases (M.M.P.) represent a family of Zinc dependent extracellular proteinases able to cleave collectively all the proteins constituting the extracellular matrix. Currently, 23 human M.M.P. have been identified and are characterized by their sequence in amino-acids and their highly conserved 3 D structure. These enzymes are expressed constitutively during the tissue remodeling process. Their over-expression in various diseases tightly related to inflammatory processes (arthritis, emphysema, cancer) described M.M.P. as choice therapeutic targets. However, as the tissue remodeling implicates modification of cellular contacts, M.M.P. appear currently as proteins involved in signalling pathways. Recent works demonstrating that M.M.P. are able to cleave substrates, which are different than proteins constituting the extracellular matrix, reinforce this vision. In order to identify the individual role and the protein expression level of M.M.P. in pathological context, we developed a new technique of functional proteomics dedicated to the detection of active forms of M.M.P. in tumour samples. This technique relied on the development of a new photoaffinity probe, based on the structure of a potent phosphinic inhibitor of M.M.P., allowing targeting and isolating active forms of M.M.P. by photoaffinity labelling. Furthermore, as the new developed probe incorporated a radioactive element, photoaffinity labelling permitted to radiolabel the targeted proteins. This probe demonstrated in vitro its remarkable ability to covalently modify the h M.M.P.-12, with a singular cross-linking yield, determined at 42 %, displaying an extremely sensitive detection (2.5 fmoles of h M.M.P.-12). When added to complex proteome, the photoaffinity probe presents the same sensibility of detection for the h M.M.P.-12 (5 fmoles); importantly, in this case, h M.M.P.-12 represents only 0.001 % of the totality of the proteins present in the sample. Moreover, this technique allows us to identify active forms of gelatinases (M.M.P.-2 and -9) in an indirect manner by comparing the results of tumour samples treated with the photoaffinity probe and the results of tumour samples analysed in zymography. These studies indicate that the protein expression levels of active forms of M.M.P. are extremely low (fmoles) and do not permit any characterisation of those forms of M.M.P. by mass spectrometry, constituting a genuine challenge which can be approached by the development of new photoaffinity probes incorporating a biotin-group. The example of this class of proteins expressed in very low abundance under active form implicates to grant efforts to develop new strategies allowing the capture of the targeted proteins. (author)

  10. Methods for determining fast neutron spectra using threshold detectors; Les methodes de determination des spectres de neutrons rapides a l'aide de detecteurs a seuil

    Energy Technology Data Exchange (ETDEWEB)

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

    1961-07-01

    We propose to examine all the methods by which fast neutron spectra can be determined using the response of threshold detectors (activation or fission chamber detectors). Most of these methods have been proposed and often even used by various authors of which a list will be found in the bibliography. The aim of the present report is thus not to present original work but rather to gather into a single article and to present in a rational form a whole series of methods which have already been described in articles scattered throughout the specialised literature. Up to the present, each author has in general studied one or two methods and no comparative study of all the possible methods seems to have been made. The most comprehensive study on this topic is that of P.M. UTHE from whose article much has been borrowed. We have tried here to develop a useful tool which should facilitate the systematic experimental study leading to the recognition of the respective merits of the methods proposed. (author) [French] On se propose d'examiner l'ensemble des methodes permettant de determiner les spectres de neutrons rapides a partir des reponses de detecteurs a seuil (detecteurs par activation ou chambre a fission). La plupart de ces methodes ont deja ete proposees, et souvent meme utilisees, par differents auteurs dont on trouvera la liste en bibliographie. Le but du present rapport n'est donc pas de faire oeuvre originale mais plutot de rassembler dans un meme document et de presenter de maniere homogene toute une serie de methodes qui ont deja fait l'objet d'articles disperses dans la litterature specialisee. Jusqu'a present, chaque auteur s'est en general limite a l'etude experimentale d'une ou deux methodes et aucune etude comparative de l'ensemble des methodes possibles ne semble avoir ete faite. Le rapport le plus complet a ce sujet est celui de P.M. UTHE auquel de larges emprunts ont ete faits. On s'est efforce ici d'elaborer un outil de travail commode qui devrait

  11. Contribution to the study of influences in emission spectrography on solutions. Application to a general analysis method for stainless steels (1961); Contribution a l'etude des influences en spectographie d'emission sur solution. Application a une methode generale d'analyse des aciers inoxydables (1961)

    Energy Technology Data Exchange (ETDEWEB)

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

    1961-11-15

    In order to establish a general method of analysis of stainless steels, by means of spark spectroscopy on solutions, a systematic study has been made of the factors involved. The variations in acidity of the solutions, or in the ratio of concentrations of two acids at constant pH, lead to a displacement of the calibration curve. Simple relations have been established between the concentration of the extraneous elements, and the effects produced, for the constituents Fe, Ti, Ni, Cr, Mn; a general method using abacus is proposed for steels containing only these elements. The interactions in the case of the elements Mo, Nb, Ta, W, were more complex, so that the simultaneous separation was studied with the help of ion-exchange resins. A general method of analysis is proposed for stainless steels. (author) [French] En vue d'etablir une methode generale d'analyse des aciers inoxydables par spectrographie d'etincelles sur solution, on a effectue une etude systematique des influences. Les variations de l'acidite des solutions ou du rapport des concentrations de deux acides a pH constant, entrainent un deplacement des courbes d'etalonnage. On a etabli des relations simples entre la teneur des tiers elements et les effets produits pour les constituants Fe, Ti, Ni, Cr, Mn; une methode generale avec abaques est proposee pour les aciers contenant ces seuls elements. Les influences dans le cas des elements Mo, Nb, Ta, W etant plus complexes, on eut a etudier la separation simultanee a l'aide de resines echangeuses d'ions. On propose une methode generale d'analyse des aciers inoxydables. (auteur)

  12. Safety precautions in atomic pile control (1962); Securite dans le controle des piles atomiques (1962)

    Energy Technology Data Exchange (ETDEWEB)

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

    1962-07-01

    We have been led to study the problem of safety in atomic pile control as a result of our participation on the one hand in the planning of C.E.A. atomic piles, and on the other hand in the pile safety sub omission considering atomic pile safety of operational or planned C.E.A. piles. We have thus had to consider the wishes occurring in piles during their operation and also their behaviour in the dynamic state The present work deals mainly with the importance of intrinsic safety devices, with the influence of reactivity variations on the power fluctuations during accidental operation, and with the development of robust and reliable safety appliances. The starting p accident has been especially studied both for low-flux piles where a compromise is necessary between the response time of the safety appliances and the statistical fluctuations and for high lux piles where xenon poisoning has an effect on the lower limit of the velocity of reactivity liberation. The desirability has been stressed of automation as a safety factor in atomic pile control. The details required for an understanding of the diagrams of the apparatus are given. (author) [French] Nous avons aborde le probleme de la securite dans le controle des piles atomiques a la suite de notre participation d'une part aux avant rojets de piles atomiques du CE.A. et d'autre part a l'examen au sein de la sous ommission de surete des piles, de la securite des piles du CE.A. en fonctionnement ou en projet. Nous avons ete amenes a nous interesser alors aux risques encourus par les piles pendant leur fonctionnement et par la meme a leur comportement en regime dynamique. Ce travail traite principalement de l'importance des securites intrinseques, de l'influence des variations de reactivite sur les evolutions de puissance en regime d'accident et du developpement d'appareillages de securite robustes et de fonctionnement tres sur. L'accident de demarrage a ete particulierement

  13. Safety precautions in atomic pile control (1962); Securite dans le controle des piles atomiques (1962)

    Energy Technology Data Exchange (ETDEWEB)

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

    1962-07-01

    We have been led to study the problem of safety in atomic pile control as a result of our participation on the one hand in the planning of C.E.A. atomic piles, and on the other hand in the pile safety sub omission considering atomic pile safety of operational or planned C.E.A. piles. We have thus had to consider the wishes occurring in piles during their operation and also their behaviour in the dynamic state The present work deals mainly with the importance of intrinsic safety devices, with the influence of reactivity variations on the power fluctuations during accidental operation, and with the development of robust and reliable safety appliances. The starting p accident has been especially studied both for low-flux piles where a compromise is necessary between the response time of the safety appliances and the statistical fluctuations and for high lux piles where xenon poisoning has an effect on the lower limit of the velocity of reactivity liberation. The desirability has been stressed of automation as a safety factor in atomic pile control. The details required for an understanding of the diagrams of the apparatus are given. (author) [French] Nous avons aborde le probleme de la securite dans le controle des piles atomiques a la suite de notre participation d'une part aux avant rojets de piles atomiques du CE.A. et d'autre part a l'examen au sein de la sous ommission de surete des piles, de la securite des piles du CE.A. en fonctionnement ou en projet. Nous avons ete amenes a nous interesser alors aux risques encourus par les piles pendant leur fonctionnement et par la meme a leur comportement en regime dynamique. Ce travail traite principalement de l'importance des securites intrinseques, de l'influence des variations de reactivite sur les evolutions de puissance en regime d'accident et du developpement d'appareillages de securite robustes et de fonctionnement tres sur. L'accident de demarrage a ete particulierement developpe aussi bien pour les piles a bas

  14. Study and development of indirect force measurement. Application to the identification of diesel engine internal sources; Etude et developpement de la mesure indirecte d'efforts. Application a l'identification des sources internes d'un moteur Diesel

    Energy Technology Data Exchange (ETDEWEB)

    Leclere, Q.

    2003-12-15

    The aim of this work is to develop a diagnostic method allowing to quantify vibratory sources of stationary operating machines from measurements. The direct measurement of sources using a force sensor is often difficult to obtain, not to say impossible. Thus, their estimation is assessed from both operating response measurements and a transfer model of the structure. Concerning the method, several original developments are put forward, especially to optimise the technique when the machine structure has an heterogeneous dynamic behaviour. Moreover, a reliability indicator of the force estimation is introduced, based on the comparison between different approaches of the transfer system inversion. The reliability of results are indeed a crucial point for indirect force measurement, because the technique is known to be very sensitive to different types of errors (measurement noise, model error). The method is applied to the identification of Diesel engine internal sources. A special attention is paid to the construction of the transfer model, estimated by both experimental and numerical approaches. Identified forces are compared to excitations computed through a simple drive train model. The comparison allows to underline some model deficiencies as well as the relative robustness of the method. A source ranking operation is realized in order to present the interest of the indirect force measurement results. (author)

  15. Entwicklung einer Methode zur monetären Bewertung des Wassers für ein Unternehmen unter Einbeziehung des Wasser-Fußabdrucks

    OpenAIRE

    Hentschel, Nora

    2011-01-01

    Wassernutzung und Abbau der Frischwasser-Ressourcen sind heutzutage ein Thema, das als so wichtig wahrgenommen wird wie der Klimawandel. Wasser wird somit zunehmend Auswirkungen auf den ökonomischen Wert von Unternehmen haben. Ziel der vorliegenden Arbeit ist es, den monetären Wert des Wassers mithilfe des Wasser-Fußabdrucks zu bestimmen. Hierfür werden nach einer kurzen Einführung in Kapitel 2 der ökologische Fußabdruck, der CO2-Fußabdruck und der Wasser-Fußabdruck kurz vorgestellt und in...

  16. Problems of method of technology assessment. A methodological analysis; Methodenprobleme des Technology Assessment; Eine methodologische Analyse

    Energy Technology Data Exchange (ETDEWEB)

    Zimmermann, V

    1993-03-01

    The study undertakes to analyse the theoretical and methodological structure of Technology Assessment (TA). It is based on a survey of TA studies which provided an important condition for theoreticall sound statements on methodological aspects of TA. It was established that the main basic theoretical problems of TA are in the field of dealing with complexity. This is also apparent in the constitution of problems, the most elementary and central approach of TA. Scientifically founded constitution of problems and the corresponding construction of models call for interdisciplinary scientific work. Interdisciplinarity in the TA research process is achieved at the level of virtual networks, these networks being composed of individuals suited to teamwork. The emerging network structures have an objective-organizational and an ideational basis. The objective-organizational basis is mainly the result of team composition and the external affiliations of the team members. The ideational basis of the virtual network is represented by the team members` mode of thinking, which is individually located at a multidisciplinary level. The theoretical `skeleton` of the TA knowledge system, which is represented by process knowledge based linkage structures, can be generated and also processed in connection with the knowledge on types of problems, areas of analysis and procedures to deal with complexity. Within this process, disciplinary knowledge is a necessary but not a sufficient condition. Metatheoretical and metadisciplinary knowledge and the correspondingly processes complexity of models are the basis for the necessary methodological awareness, that allows TA to become designable as a research procedure. (orig./HP) [Deutsch] Die Studie stellt sich die Aufgabe, die theoretische und methodische Struktur des Technology Assessment (TA) zu analysieren. Sie fusst auf Erhebungen, die bei Technology-Assessment-Studien vorgenommen wurden und die wesentliche Voraussetzungen fuer

  17. Modelisation des emissions de particules microniques et nanometriques en usinage

    Science.gov (United States)

    Khettabi, Riad

    La mise en forme des pieces par usinage emet des particules, de tailles microscopiques et nanometriques, qui peuvent etre dangereuses pour la sante. Le but de ce travail est d'etudier les emissions de ces particules pour fins de prevention et reduction a la source. L'approche retenue est experimentale et theorique, aux deux echelles microscopique et macroscopique. Le travail commence par des essais permettant de determiner les influences du materiau, de l'outil et des parametres d'usinage sur les emissions de particules. E nsuite un nouveau parametre caracterisant les emissions, nomme Dust unit , est developpe et un modele predictif est propose. Ce modele est base sur une nouvelle theorie hybride qui integre les approches energetiques, tribologiques et deformation plastique, et inclut la geometrie de l'outil, les proprietes du materiau, les conditions de coupe et la segmentation des copeaux. Il ete valide au tournage sur quatre materiaux: A16061-T6, AISI1018, AISI4140 et fonte grise.

  18. Monte-Carlo method - codes for the study of criticality problems (on IBM 7094); Methode de Monte- Carlo - codes pour l'etude des problemes de criticite (IBM 7094)

    Energy Technology Data Exchange (ETDEWEB)

    Moreau, J; Rabot, H; Robin, C [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1965-07-01

    The two codes presented here allow to determine the multiplication constant of media containing fissionable materials under numerous and divided forms; they are based on the Monte-Carlo method. The first code apply to x, y, z, geometries. The volume to be studied ought to be divisible in parallelepipeds, the media within each parallelepiped being limited by non-secant surfaces. The second code is intended for r, 0, z geometries. The results include an analysis of collisions in each medium. Applications and examples with informations on time and accuracy are given. (authors) [French] Les deux codes presentes dans ce rapport permettent la determination des coefficients de multiplication de milieux contenant des matieres fissiles sous des formes tres variees et divisees, ils reposent sur la methode de Monte-Carlo. Le premier code s'applique aux geometries x, y, z, le volume a etudier doit pouvoir etre decompose en parallelepipedes, les milieux a l'interieur de chaque parallelepipede etant limites par des surfaces non secantes. Le deuxieme code s'applique aux geometries r, 0, z. Les resultats comportent une analyse des collisions dans chaque milieu. Des applications et des exemples avec les indications de temps et de precision sont fournis. (auteurs)

  19. Measurement of electro-sprayed 238 and 239+240 plutonium isotopes using 4{pi}-alpha spectrometry. Application to environmental samples; Spectrometrie alpha 4{pi} de sources d'actinides realisees par electronebulisation. Developpement et optimisation d'un protocole applique au mesurage des isotopes 238 et 239+240 du plutonium dans l'environnement

    Energy Technology Data Exchange (ETDEWEB)

    Charmoille-Roblot, M. [CEA/Fontenay-aux-Roses, Dept. de Protection de l' Environnement (DPRE), 92 (France)]|[Paris-11 Univ., 91 - Orsay (France)

    1999-07-01

    A new protocol for plutonium deposition using the electro-spray technique coupled with 4{pi}-{alpha} spectrometry is proposed to improve the detection limit, shorten the counting time. In order to increase the detection efficiency, it was proposed to measure 238 and 239+240 plutonium isotopes electro-sprayed deposit simultaneously on both sides of the source support, that must be as transparent as possible to alpha-emissions, in a two-alpha detectors chamber. A radiochemical protocol was adapted to electro-spray constraints and a very thin carbon foil was selected for 4{pi} -alpha spectrometry. The method was applied to a batch of sediment samples and gave the same results as an electrodeposited source measured using conventional alpha spectrometry with a 25 % gain on counting time and 10 % on plutonium 238 detection limit. Validation and application of the technique have been made on reference samples. (author)

  20. High-Dose Ionizing Radiation Photographic Dosimetry; Mesure, par des Methodes Photogra Phiques, de Doses Elevees de Rayonnements Ionisants; 0424 041e 0422 041e 0413 0420 0414 ; Dosimetria Fotografica de Dosis Elevadas de Radiaciones Ionizantes

    Energy Technology Data Exchange (ETDEWEB)

    Trousil, J.; Bucina, I. [Institute for Research Production and Application of Radioisotopes Prague, Czechoslovakia (Czech Republic)

    1965-06-15

    pour la detection de doses elevees de rayonnements et compare les merites respectifs des films FOMA et ORWO pour la mesure des doses elevees. Des progres ont egalement ete faits dans la mesure de doses elevees de rayonnements, a savoir la methode du developpement freine, decrite plus loin, dans laquelle des substances du type nitrobenzimidazole et benzotriazole sont utilisees a des concentrations appropriees dans le revelateur. Dans le cas d'emulsions lentes a forte teneur en argent, cette technique permet de mesurer des expositions a des doses gamma (rayons X de haute energie) allant jusqu'a 10s r ou meme davantage, si l 'on ne demande pas d'evaluations precises dans la gamme allant jusqu' a 100 r. Le memoire decrit l ' effet de freinage des produits chimiques ajoutes aux revelateurs sur les emulsions rapides et lentes a fortes teneur en argent. On a demontre que dans les emulsions utilisees pour la mesure de doses elevees de rayonnements intenses et traitees dans le revelateur auquel des produits chimiques de freinage ont ete ajoutes, les effets des variations en fonction de l'energie et l ' affaiblissement de l'image latente influent sur la precision des mesures. En conclusion, le memoire decrit les erreurs de dosimetrie photographique des rayonnements intenses qui ont ete decelees par des methodes statistiques mathematiques a partir de travaux experimentaux. Il est egalement question de l'accroissement de l'erreur dans les valeurs correspondant aux noircissements faibles et intenses. Les auteurs ont tenu compte egalement des erreurs dues a l'etalonnage des appareils, aux variations en fonction de l'energie, a l'affaiblissement de l'image latente, au traitement chimique et a la mesure du noircissement. La presomption que la dose mesuree par le detecteur a film correspond a la dose a l'organisme entier constitue une erreur qui n'est pas prise en consideration. (author) [Spanish] Los autores describen un metodo fotografico de medicion de dosis de radiaciones

  1. Methodological developments and qualification of calculation schemes for the modelling of photonic heating in the experimental devices of the future Jules Horowitz material testing reactor (RJH); Developpements methodologiques et qualification de schemas de calcul pour la modelisation des echauffements photoniques dans les dispositifs experimentaux du futur reacteur d'irradiation technologiques Jules Horowitz (RJH)

    Energy Technology Data Exchange (ETDEWEB)

    Blanchet, D

    2006-07-01

    The objective of this work is to develop the modelling of the nuclear heating of the experimental devices of the future Jules Horowitz material testing reactor (RJH). The strong specific nuclear power produced (460 kW/l), induces so intense photonic fluxes which cause heating and large temperature gradients that it is necessary to control it by an adequate design. However, calculations of heating are penalized by the very large uncertainties estimated at a value of about 30% (2*{sigma}) coming from the gaps and uncertainties of the data of gamma emission present in the libraries of basic nuclear data. The experimental program ADAPh aims at reducing these uncertainties. Measurements by thermoluminescent detectors (TLD) and ionisation chambers are carried out in the critical assemblies EOLE (Mox) and Minerve (UO{sub 2}). The rigorous interpretation of these measurements requires specific developments based on Monte-Carlo simulations of coupled neutron-gamma and gamma-electron transport. The developments carried out are made different in particular by the modelling of cavities phenomena and delayed gamma emissions by the decay of fission products. The comparisons calculation-measurement made it possible to identify a systematic bias confirming a tendency of calculations to underestimate measurements. A Bayesian method of adjustment was developed in order to re-estimate the principal components of the gamma heating and to transpose the results obtained to the devices of the RJH, under conditions clearly and definitely representative. This work made possible to reduce significantly the uncertainties on the determination of the gamma heating from 30 to 15 per cent. (author)

  2. Study of link transitions between superdeformed well and normally deformed well in Hg{sup 192} and research and development for a new concept of {gamma} photons detection: the Agata array; Etude des liens entre puits superdeforme et puits normalement deforme dans {sup 192}Hg et recherche et developpement pour un nouveau concept de detection de photons {gamma}: le multidetecteur AGATA

    Energy Technology Data Exchange (ETDEWEB)

    Roccaz, J

    2006-07-15

    The atomic nucleus can adopt a very elongated shape with an axis ratio 2:1, this is the superdeformation phenomenon. Nowadays more than 300 superdeformed bands have been identified at high spin, but the determination of excitation energies, spins and parities of the associated states have been established for only one tenth of these bands. The former quantities (E{sup *}, I, {pi}) can only be determined via the linking gamma-transitions between the superdeformed (sd) and the normally deformed (nd) states. Within the framework of this thesis, we have investigated the Hg{sup 192} nucleus in order to establish E{sup *}, I and {pi}. This nucleus is predicted to be doubly magic at superdeformation and hence is taken as a reference in the mass {approx} 190 region. The experiment was carried out at Strasbourg using the Euroball-IV array and the vivitron accelerator. The obtained results are not convincing and seem to be at the limit of the performances of Euroball. Next generation of arrays will abandon the Compton-shields and use tracking concept to reconstruct the trajectories of incident photons, and therefore we expect a huge increase of efficiency. The second part of this work was focused on the research and development work for the AGATA (Advanced GAmma Tracking Array) project. We have performed simulations with the GEANT-4 code and developed tracking methods to reconstruct pair-creation events. The full AGATA will be operational around 2015 and will enhance by around two orders of magnitude the observational limits. (author)

  3. Methodological developments and qualification of calculation schemes for the modelling of photonic heating in the experimental devices of the future Jules Horowitz material testing reactor (RJH); Developpements methodologiques et qualification de schemas de calcul pour la modelisation des echauffements photoniques dans les dispositifs experimentaux du futur reacteur d'irradiation technologiques Jules Horowitz (RJH)

    Energy Technology Data Exchange (ETDEWEB)

    Blanchet, D

    2006-07-01

    The objective of this work is to develop the modelling of the nuclear heating of the experimental devices of the future Jules Horowitz material testing reactor (RJH). The strong specific nuclear power produced (460 kW/l), induces so intense photonic fluxes which cause heating and large temperature gradients that it is necessary to control it by an adequate design. However, calculations of heating are penalized by the very large uncertainties estimated at a value of about 30% (2*{sigma}) coming from the gaps and uncertainties of the data of gamma emission present in the libraries of basic nuclear data. The experimental program ADAPh aims at reducing these uncertainties. Measurements by thermoluminescent detectors (TLD) and ionisation chambers are carried out in the critical assemblies EOLE (Mox) and Minerve (UO{sub 2}). The rigorous interpretation of these measurements requires specific developments based on Monte-Carlo simulations of coupled neutron-gamma and gamma-electron transport. The developments carried out are made different in particular by the modelling of cavities phenomena and delayed gamma emissions by the decay of fission products. The comparisons calculation-measurement made it possible to identify a systematic bias confirming a tendency of calculations to underestimate measurements. A Bayesian method of adjustment was developed in order to re-estimate the principal components of the gamma heating and to transpose the results obtained to the devices of the RJH, under conditions clearly and definitely representative. This work made possible to reduce significantly the uncertainties on the determination of the gamma heating from 30 to 15 per cent. (author)

  4. Application of a gamma spectroscopy system to the measurement of neutron cross sections necessary to the development of nuclear energy; Mise au point d'un systeme de spectroscopie pour mesurer des sections efficaces neutroniques applicables a un possible developpement du nucleaire comme source d'energie

    Energy Technology Data Exchange (ETDEWEB)

    Deruelle, O

    2002-09-01

    This work concerns the development of nuclear energy and nuclear waste management in particular. Two parts of this study can be distinguished. In the first part (theoretical), a thorium-plutonium fuel based on MOX and dedicated for PWR was investigated in order to transmute plutonium in a potentially low waste fuel cycle. It was shown that this type of fuel is not regenerative but could be used for a transition to the industrial thorium fuel cycle without building new reactors. Thanks to moderated neutron spectra and high loaded actinide mass in the core, U-233 is quickly created ({approx}300 kg/y) for a loss of about {approx}1200 kg of fissile plutonium. In the second part (experimental), we have developed and built a new reaction chamber to measure neutron cross sections of actinides by alpha-gamma spectroscopy. This experimental device (in principle transportable) was commissioned in the high flux reactor of ILL Grenoble. Neutron flux was measured by gamma spectroscopy of irradiated Al and Co samples and was found to be of the order of 6,0. 10{sup 14} n.cm{sup -2}.s{sup -1} (4%). By the irradiation of 11{mu}g of Am-243 and Pu-242, corresponding capture cross sections were measured in the thermal neutron flux at 50 deg C. These are the results: {sup 243}Am(n,{gamma}) {sup 244fond.}Am = 4,72{+-}1,42b; {sup 243}Am(n,{gamma}) {sup 244total}Am = 74,8{+-}3,25b; {sup 242}Pu (n,{gamma}){sup 243}Pu = 22,7{+-}1,09b. Uncertainties of the measurements are mostly due to the determination of the neutron flux, efficiency of the electronics and ambiguities related to the definition of the area under {alpha}-{gamma} spectra. Although our measured cross sections deviate (by 10-30%) from the corresponding values widely used in evaluated data libraries such as ENDF, JEF and JENDL, in this work we have demonstrated the feasibility and principle of our experimental method. Furthermore, the value for the 243-americium capture cross-section is in very good agreement with the last two

  5. Application of a gamma spectroscopy system to the measurement of neutron cross sections necessary to the development of nuclear energy; Mise au point d'un systeme de spectroscopie pour mesurer des sections efficaces neutroniques applicables a un possible developpement du nucleaire comme source d'energie

    Energy Technology Data Exchange (ETDEWEB)

    Deruelle, O

    2002-09-01

    This work concerns the development of nuclear energy and nuclear waste management in particular. Two parts of this study can be distinguished. In the first part (theoretical), a thorium-plutonium fuel based on MOX and dedicated for PWR was investigated in order to transmute plutonium in a potentially low waste fuel cycle. It was shown that this type of fuel is not regenerative but could be used for a transition to the industrial thorium fuel cycle without building new reactors. Thanks to moderated neutron spectra and high loaded actinide mass in the core, U-233 is quickly created ({approx}300 kg/y) for a loss of about {approx}1200 kg of fissile plutonium. In the second part (experimental), we have developed and built a new reaction chamber to measure neutron cross sections of actinides by alpha-gamma spectroscopy. This experimental device (in principle transportable) was commissioned in the high flux reactor of ILL Grenoble. Neutron flux was measured by gamma spectroscopy of irradiated Al and Co samples and was found to be of the order of 6,0. 10{sup 14} n.cm{sup -2}.s{sup -1} (4%). By the irradiation of 11{mu}g of Am-243 and Pu-242, corresponding capture cross sections were measured in the thermal neutron flux at 50 deg C. These are the results: {sup 243}Am(n,{gamma}) {sup 244fond.}Am = 4,72{+-}1,42b; {sup 243}Am(n,{gamma}) {sup 244total}Am = 74,8{+-}3,25b; {sup 242}Pu (n,{gamma}){sup 243}Pu = 22,7{+-}1,09b. Uncertainties of the measurements are mostly due to the determination of the neutron flux, efficiency of the electronics and ambiguities related to the definition of the area under {alpha}-{gamma} spectra. Although our measured cross sections deviate (by 10-30%) from the corresponding values widely used in evaluated data libraries such as ENDF, JEF and JENDL, in this work we have demonstrated the feasibility and principle of our experimental method. Furthermore, the value for the 243-americium capture cross-section is in very good agreement with the last two

  6. The C{sub n} method for approximation of the Boltzmann equation; La methode C{sub n} d'approximation de l'equation de Boltzmann

    Energy Technology Data Exchange (ETDEWEB)

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

    1968-01-15

    In a new method of approximation of the Boltzmann equation, one starts from a particular form of the equation which involves only the angular flux at the boundary of the considered medium and where the space variable does not appear explicitly. Expanding in orthogonal polynomials the angular flux of neutrons leaking from the medium and making no assumption about the angular flux within the medium, very good approximations to several classical plane geometry problems, i.e. the albedo of slabs and the transmission by slabs, the extrapolation length of the Milne problem, the spectrum of neutrons reflected by a semi-infinite slowing down medium. The method can be extended to other geometries. (authors) [French] On etablit une nouvelle methode d'approximation pour l'equation de Boltzmann en partant d'une forme particuliere de cette equation qui n'implique que le flux angulaire a la frontiere du milieu et ou les variables d'espace n'apparaissent pas explicitement. Par un developpement en polynomes orthogonaux du flux angulaire sortant du milieu et sans faire d'hypothese sur le flux angulaire a l'interieur du milieu, on obtient de tres bonnes approximations pour plusieurs problemes classiques en geometrie plane: l'albedo et le facteur de transmission des plaques, la longueur d'extrapolation du probleme de Milne, le spectre des neutrons reflechis par un milieu semi-infini ralentisseur. La methode se generalise a d'autres geometries. (auteurs)

  7. The future of new calculation concepts in dosimetry based on the Monte Carlo Methods; Avenir des nouveaux concepts des calculs dosimetriques bases sur les methodes de Monte Carlo

    Energy Technology Data Exchange (ETDEWEB)

    Makovicka, L.; Vasseur, A.; Sauget, M.; Martin, E.; Gschwind, R.; Henriet, J. [Universite de Franche-Comte, Equipe IRMA/ENISYS/FEMTO-ST, UMR6174 CNRS, 25 - Montbeliard (France); Vasseur, A.; Sauget, M.; Martin, E.; Gschwind, R.; Henriet, J.; Salomon, M. [Universite de Franche-Comte, Equipe AND/LIFC, 90 - Belfort (France)

    2009-01-15

    Monte Carlo codes, precise but slow, are very important tools in the vast majority of specialities connected to Radiation Physics, Radiation Protection and Dosimetry. A discussion about some other computing solutions is carried out; solutions not only based on the enhancement of computer power, or on the 'biasing'used for relative acceleration of these codes (in the case of photons), but on more efficient methods (A.N.N. - artificial neural network, C.B.R. - case-based reasoning - or other computer science techniques) already and successfully used for a long time in other scientific or industrial applications and not only Radiation Protection or Medical Dosimetry. (authors)

  8. RECHERCHES SUR LE DEVELOPPEMENT DES COCKTAILS AVEC UN POTENTIEL ANTIOXYDANT ELEVE

    Directory of Open Access Journals (Sweden)

    Daniela Istrati

    2010-12-01

    Full Text Available The research aimed to study the influence of the extraction process on the content of antioxidant compounds present in four types of tea and establishing of the optimal conditions for preparation of cocktails in whose composition is combined the beneficial effect of foods rich in antioxidants and vitamins: green tea, exotic fruits, berries and honey. Content of antioxidants, protein, fiber, vitamins and minerals from unfermented tea is supplemented by high concentration of biological active compounds in fruits and honey used. A positive correlation between substances added with significant increase of antioxidant and nutritive potential has been observed. This study confirms that the synergistic action of green tea, fruits and honey allowed obtaining attractive drinks from sensorial point of view and compounds with high antioxidant potential content.

  9. Developpement d'un film antibacterien ayant des proprietes de glissement pour une meilleure processabilite

    Science.gov (United States)

    Silverwood, Richard

    Product safety is of crucial importance for the food industry. The challenge of food safety is evidenced by the number of food poisoning in Canada and worldwide. An outbreak of listeriosis in 2008, having put the safety of Canadians at risk, has motivated the revision of the strategy for food safety in Canada. In this context, a collaboration between two major industrial players in Quebec and École Polytechnique de Montréal was initiated. This collaboration is supported by the creation of the Research Chair for safe, smart and sustainable food. One of the many forefront projects of this research chair is to develop a package having a bactericidal effect. Many compounds are currently available for incorporation into a finished product. Zinc Omadine™ by ArchChemicals and Irgaguard™ by BASF are some examples of products that have proven themselves. However, the incorporation of a bactericidal agent in a product having a direct contact with food must meet certain safety criteria. Thus, an overview of various antibacterial agents is made in terms of their effectiveness and their potential use in packaging a food product. To date, no technology allows easy incorporation of an antibacterial agent in a polymer matrix. Antibacterial constituents of the mixture with the polymer melt will provide the simplicity pursued. We chose nano zinc oxide as the main antibacterial agent for its mode of action, its great potential for sustainability and its ability not to migrate out of the polyethylene polymer matrix. Moreover, the effect of trace element at very low concentrations is validated. To increase efficiency, good dispersion is achieved by adding a polyethylene with maleic anhydride grafted groups. The increase in antibacterial properties by this change has been proven. Although these films exhibit a marked bactericidal effect, a lack of persistence of the antibacterial effect was noticed. This is probably due to a rearrangement of the molecular structure on the surface. This rearrangement, due to the polar nature of particles, inhibits the antibacterial effect of the particles, causing them to migrate to a critical distance, outside their scope. Furthermore, we evaluated briefly some other antibacterial agents. Calcium oxide (CaO) demonstrated, although lower than ZnO, an interesting antibacterial potential. The specificity of the bactericidal for gram-positive bacteria for this variance. The addition of iron oxide (Fe2O3) did not, by its hydrophilic properties, increase the bactericidal properties of CaO, simply by mixing them. Also, the use of thymol (component of essential oil of thyme) was effective, even at very low doses. A question mark hangs, however, the sustainability of such an agent. Its use in conjunction with a compatibilizer could result in a much more persistent bactericidal effect, slowing the process of migrating to the film surface. This effect is reduced when the bactericidal thymol is mixed with ZnO in the polyethylene matrix. Finally, a tool for optimizing slip additives was developed. To do this, a correlation that links the absorbance in infrared spectroscopy (ATR reflection) to the surface concentration of the lubricant was developed. By using this correlation, also called master curve, and an infrared spectrometer to test an unknown film, it is possible to find the initial concentration of slip additive. These studies highlight the potential use of zinc oxide and thymol as efficient bactericidal agent for the food industry. This work represents the first effort to develop an antibacterial film, involving nanoscale metal oxides and a polymer matrix of polyolefin.

  10. Policy of developing alternate vehicles; La politique de developpement des vehicules alternatifs

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-06-15

    In most western cities the present-day car is by far the principal mode of transport. The wrong side of it is that automobile circulation is a source of air-pollution, noise and traffic jam, inconveniences against which public opinion shows itself more and more susceptible. Facing this situation governments in succession have since several years encouraged by different measures the development of fitted or alternative vehicles: electric, natural gas (NG) fuelled and liquefied petroleum gas (LPG) vehicles. These vehicles have the advantage of responding both to pollution problem and energy diversification challenge. The present-day regulation system gathers a number of attractive provisions: - maintaining para-fiscal taxes upon gas fuels at a level much lower than for other fuels; - VAT refunding for these gas fuels and electricity consumed by vehicles of this type; - general councils can be totally or partially exonerated from automobile taxation; - assigning future green label allowing these vehicles to be excepted from traffic restrictions applied to cope with pollution peaks. Other additional advantages are provided by the law on air and rational use of energy of 30 December 1996. Merits and drawbacks of each of the mentioned types of alternative vehicles are reviewed. So, although entirely un-polluting the electric cars are not cheap and what is even more hindering is their very limited range which for current batteries does not exceed 80 km. Only little over 3000 electric vehicles were sold, a third of them to EDF. The natural gas is rather pure a fuel at burning of which the release of sulfur and solid particles are practically negligible. Due to its characteristics, the short and medium term development of this alternative seems to reside only in buses and service vehicles, the only able to support the supplementary load of high pressure gas tanks. Being formed of liquefied butane and propane at low pressure, LPG is as attractive as NG, with respect to the harmful gas releases. Since 1996 the state has reduced the fiscality to a particularly low level that reduced significantly the price. This induced a fast development of the LPG alternative; the consumption was tripled from 1995 to 1997 and the number of LPG vehicles, almost all adapted to bi-carburation (gasoline/LPG) has grown continuously. To date the LPG fleet amounts up to 70,000 vehicles and it could reach by the end of 2000 the number of 300,000 vehicles.

  11. AREVA sustainable development indicators guidelines; Guide methodologique des indicateurs developpement durable AREVA

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2003-12-01

    These guidelines set out the procedures used to measure and report the sustainable development and continuous progress data and indicators used within the Areva Group. It defines the scope of the guide, the list of indicators, the measurement and calculation procedures, the internal and external audits. (A.L.B.)

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1962-04-15

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

  13. Contribution to the tectonic characterization of fractured reservoirs, I: photo-elasticimetric modelling of the stress perturbations near faults and the associated fracture network: application to oil reserves, II mechanisms for the 3D joint organization in a natural reservoir analogue (flat-lying Devonian Old Red Sandstones of Caitness in North Scotland); Contribution a la caracterisation tectonique des reservoirs fractures, I: modelisation photoelecticimetrique des perturbations de contrainte au voisinage des failles et de la fracturation associee: application petroliere, II: mecanismes de developpement en 3D des diaclases dans un analogue de reservoir, le Devonien tabulaire du caithness (Ecosse)

    Energy Technology Data Exchange (ETDEWEB)

    Auzias, V

    1995-10-27

    In order to understand joint network organisation in oil reservoirs, as a first step we have adapted to technique (the photo-elasticimetry) to study stress fields in 2D. This method allows to determine the principal stress trajectories near faults, as well as the associated joint network organisation. Natural joint networks perturbed near faults are modeled and the parameters that control stress perturbation are proposed. With the aim of extrapolating joint data from a well to the entire reservoir our modelling is based on both 3 D seismic data and local joint data. The second part of our research was dedicated to studying joint propagation mechanisms in a natural reservoir analogue (flat-lying Devonian Old Red Sandstones of Caitness in North Scotland). Several exposure observation at different scales and in 3D (horizontal and cliff sections) allow to reconstitute the fracturing geometry from centimeter to kilometer scale and to link these to the regional tectonic history. This study shows that it is possible to differentiate three types of joints major joints, `classic` joints and micro-joints, each with different vertical persistence. New concepts on the 3D joint organisation have been deduced from field quantitative data, which can be applied to reservoir fracture modeling. In particular the non-coexistence phenomenon in a single bed of two regional joint sets with close strikes. Some joint development mechanisms are discussed: interaction between joints and sedimentary interfaces, joint distribution near faults, origin of en echelon arrays associated with joints. (author) 142 refs.

  14. Separation method for rare-earths using high-voltage electrophoresis on paper strip; Methode de separation des terres rares par electrophorese a haute tension sur papier - support

    Energy Technology Data Exchange (ETDEWEB)

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

    1966-07-01

    The equipment includes an electrophoresis set running at 3 000 V and 20 mA. Two cooling plates are used as heat exchanger, and a pneumatic pressure device to insure an uniform pressure on the paper strip laid flat. The mobilities and the separations of the rare earths in lactic, and, {alpha} hydroxy-isobutyric acid solutions are investigated on cellulose acetate strip. Better results are obtained with {alpha} hydroxy-isobutyric acid. The method is rapid and allows a fine fractionation of rare earth elements within less than an hour. A complete separation of a Ce - Pr - Nd - Pm - Eu mixture, and a Y - Tb mixture is obtained. (author) [French] L'equipement comporte un appareil d'electrophorese fonctionnant sous 3000 V a 20 mA. Deux plaques refrigerantes absorbent la chaleur dissipee, et un coussin pneumatique assure une pression uniforme sur le papier support. Les mobilites et les separations des terres rares sont etudiees en milieux lactiques et {alpha} hydroxyisobutyriques sur papier d'acetate de cellulose. De meilleurs resultats sont obtenus avec l'acide {alpha} hydroxyisobutyrique. La methode est tres rapide et permet de separer un melange de terres rares radioactives en moins d'une heure. Des separations fines d'un melange Ce, Pr, Nd, Pm, Eu, et d'un melange Y, Tb sont egalement obtenues. (auteur)

  15. Die Relevanz des Gruppendiskussionsverfahrens und der dokumentarischen Methode für die medienpädagogische Professionsforschung

    Directory of Open Access Journals (Sweden)

    Stefan Welling

    2008-02-01

    Full Text Available Ausgehend von der Notwendigkeit einer qualitativ-empirisch fundierten medienpädagogischen Professionsforschung erörtert der Beitrag, wie das Gruppendiskussionsverfahren für diesen Zweck nutzbar gemacht werden kann. Anhand der exemplarischen Rekonstruktion medienpädagogischer Orientierungsmuster von in der offenen Jugendarbeit tätigen Pädagogen/-innen mit Hilfe der dokumentarischen Methode wird die praktische Anwendung des Verfahrens demonstriert und kritisch reflektiert. Dabei wird u. a. deutlich, dass das Gruppendiskussionsverfahren gut geeignet ist, zur Schliessung existierender Lücken der medienpädagogischen Professionsforschung beizutragen und gleichzeitig einen vielversprechenden Ansatz zur Entwicklung einer regelmässig eingeforderten reflexiven Professionalisierung zu leisten vermag.

  16. Methods and experimental coefficients used in the computation of reactor shielding; Methodes et coefficients experimentaux pour le calcul des protections de reacteurs

    Energy Technology Data Exchange (ETDEWEB)

    Bourgeois, J; Lafore, P; Millot, J P; Rastoin, J; Vathaire, F de [Commissariat a l' Energie Atomique, Saclay (France).Centre d' Etudes Nucleaires

    1959-07-01

    1) The concept of an effective removal cross section has been developed in order more easily to compute reactor shielding thicknesses. We have built an experimental facility for the purpose of measuring effective removal cross sections, the value of which had not been published at that time. The first part of this paper describes the device or facility used, the computation method applied, and the results obtained. 2) Starting from this concept, we endeavoured to define a removal cross section as a function of energy. This enabled us to use the method for computations bearing on the attenuation of fast neutrons of any spectrum. An experimental verification was carried out for the case of fission neutrons filtered by a substantial thickness of graphite. 3) Finally, we outline a computation method enabling us to determine the sources of captured gamma rays by the age theory and we give an example of the application in a composite shield. (author) [French] 1) La notion de section efficace effective de deplacement a ete introduite pour calculer commodement les epaisseurs de protection des reacteurs. Nous avons construit un dispositif experimental destine a mesurer les sections efficaces effectives de deplacement dont la valeur n'avait pas ete publiee a cette epoque. La premiere partie de cette communication decrit le dispositif utilise, la methode de calcul employee et les resultats obtenus. 2) A partir de cette notion, nous avons essaye de definir une section efficace de deplacement fonction de l'energie. Ceci permet d'utiliser la methode du deplacement pour des calculs d'attenuation de neutrons rapides dont le spectre est quelconque. Une verification experimentale a ete faite dans le cas de neutrons de fission filtres par une epaisseur notable de graphite. 3) Enfin une methode de calcul permettant de determiner les sources de gamma de capture par la theorie de l'age est exposee et un exemple d'application donne dans une protection composite. (auteur)

  17. Etude d'integration fonctionnelle du cycle de developpement des produits et des communautes de pratique virtuelles

    Science.gov (United States)

    Doumit, Nancy

    Product development, subject to time constraints and system complexity, needs synchronous communication between different disciplines and locations in order to enable knowledge sharing. Being well supported, informal information flow increases productivity during product realization. Therefore, manufacturing industries are exploring the use of Enterprise Social Media (ESM) functionalities. This thesis explores the functional integration of formal information technologies such as Product Lifecycle Management (PLM) software with informal technologies as ESM through an industrial case study. Reviewing literature, the candidate has identified a gap between Virtual Communities of Practice (VCoP) and product development, as well as the correlation of PLM solutions and noncontrolled ESM in the aerospace industry. In order to disseminate a descriptive study of the current collaboration status, the author has undertaken online surveys for geodistant employees of the same department, semi-structured interviews and research among existing documentations. Subsequently, a Quality Functional Analysis is performed via two modified House of Quality matrices (PLM and ESM) to assign a convenient support for information transfer independently of its content maturity. Users' needs are categorized, and for each category a choice of platform is made with further recommendation regarding the use of the function or the need of human intervention. VCoP form an integrated part of the solution where employees support the technical content. Thus, essential roles and responsibilities are presented to maintain existing CoP and develop new ones. Finally, the candidate presents the limits of this research, gives recommendations for the manufacturing industry and suggests potential continuation of this study using PLM 2.0 with noncontrolled ESM tools.

  18. The influence of xenon poisoning in high-flux reactors on the choice of control rod speeds (1961); Influence de l'empoisonnement xenon dans les piles a haut flux sur le choix de la vitesse des barres de controle (1961)

    Energy Technology Data Exchange (ETDEWEB)

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

    1961-07-01

    - The general laws are restated concerning the changes in xenon and iodine concentrations in thermal neutron reactors, assuming an uniform neutron flux distribution in the core. It is shown how the evolution in the xenon poisoning influences the selection of the control rod speed, at start-up. Certain simple methods of calculation are developed making it possible to resolve the problem of the choice of this speed in the case where the xenon poisoning is taken into account. (author) [French] - On rappelle les lois generales relatives aux evolutions de concentration xenon et iode dans les piles atomiques a neutrons thermiques lorsqu'on suppose une repartition uniforme du flux de neutrons dans le coeur. On montre comment l'evolution de l'empoisonnement xenon influe sur le choix de la vitesse des barres de controle en periode de demarrage. On developpe certaines methodes de calculs simples permettant de resoudre le probleme du choix de la vitesse des barres de controle, dans le cas ou l'on tient compte de l'empoisonnement xenon. (auteur)

  19. Methods and experimental coefficients used in the computation of reactor shielding; Methodes et coefficients experimentaux pour le calcul des protections de reacteurs

    Energy Technology Data Exchange (ETDEWEB)

    Bourgeois, J; Lafore, P; Millot, J P; Rastoin, J; Vathaire, F de [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1958-07-01

    1. The concept of an effective removal cross section has been developed in order more easily to compute reactor shielding thicknesses. We have built an experimental facility for the purpose of measuring effective removal cross sections, the value of which had not been published at that time. The first part of this paper describes the device or facility used, the computation method applied, and the results obtained. 2. Starting from this concept, we endeavored to define a removal cross section as a function of energy. This enabled us to use the method for computations bearing on the attenuation of fast neutrons of any spectrum. An experimental verification was carried out for the case of fission neutrons filtered by a substantial thickness of graphite. 3. Finally, we outline a computation method enabling us to determine the sources of captured gamma rays by the age theory and we give an example of the application in a composite shield. (author)Fren. [French] 1. La notion de section efficace effective de deplacement a ete introduite pour calculer commodement les epaisseurs de protection des reacteurs. Nous avons construit un dispositif experimental destine a mesurer les sections efficaces effectives de deplacement dont la valeur n'avait pas ete publiee a cette epoque. La premiere partie de cette communication decrit le dispositif utilise, la methode de calcul employee et les resultats obtenus. 2. A partir de cette notion, nous avons essaye de definir une section efficace de deplacement fonction de l'energie. Ceci permet d'utiliser la methode du deplacement pour des calculs d'attenuation de neutrons rapides dont le spectre est quelconque. Une verification experimentale a ete faite dans le cas de neutrons de fission filtres par une epaisseur notable de graphite. 3. Enfin une mde de calcul permettant de determiner les sources de gamma de capture par la theorie de l'age est exposee et un exemple d'application donne dans une protection composite. (auteur)

  20. Agence Francaise de Developpement. Strategic Orientation Plan 2012-2016

    International Nuclear Information System (INIS)

    2012-01-01

    Agence Francaise de Developpement (AFD) is a development finance institution that has been working to fight poverty and foster economic growth in developing countries and the French Overseas Communities for more than seventy years. It executes the policy defined by the French Government. AFD is present on five continents where it has an international network of 71 agencies and representation offices, including 9 in the French Overseas Communities and 1 in Brussels. It finances and supports projects that support more sustainable and shared economic growth, improve living conditions for the poorest, contribute to protecting the planet and help stabilize fragile or post-conflict states. It subsidiary, Proparco, supports private investment. AFD also works with French and international academic networks to feed into debates and forward planning on development. In 2011, AFD approved nearly euro 6.9 billion to finance activities in developing countries and the French Overseas Communities. The funds will help get 4 million children into primary school and 2 million into secondary school; they will also improve drinking water supply for 1.53 million people. Energy efficiency projects financed by AFD in 2011 will save nearly 3.8 million tons of CO_2 equivalent annually. After ten years of strong growth and substantial transformation at AFD, the third Strategic Orientation Plan (POS3) builds on the potential it has acquired. It aims to strengthen AFD and situate it within the framework of the new 'partnership for development' promoted by the French Government. In a rapidly changing international environment, AFD is underscoring its strategy to finance long-term development activities. The aim is to help communities build sustainable conditions to allow them to meet their priority needs, without compromising the ability of future generations to meet their needs. The attention given to the social and environmental dimensions of the projects it finances, along with their impact

  1. Physics of phenomena in the zone close to an underground nuclear explosion; Physique des phenomenes en zone proche des explosions nucleaires souterraines

    Energy Technology Data Exchange (ETDEWEB)

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

    1969-07-01

    After a description of the phenomenology of underground explosions, the basic laws governing the propagation in the ground of the energy produced by the explosion are given. The reports considers hydrodynamics, the mechanics of solids, the equations of state for solids and gases in the case of very high and medium pressures, and the dynamical strength of solids. These various elements make it possible to draw up a system of equations which define completely the changes with time of the shock-wave produced in the ground by the explosion. (authors) [French] Apres une description de la phenomenologie des explosions souterraines, on expose les lois fondamentales regissant la propagation dans le sol de l'energie degagee par l'explosion. L'expose comprend des developpements sur l'hydrodynamique, la mecanique des solides, les equations d'etat des solides et des gaz, aux tres fortes et moyennes pressions, et sur la resistance dynamique des solides. Ces differents elements permettent d'ecrire un systeme d'equations qui definissent completement l'evolution dans le temps de l'onde de choc emise dans le sol par l'explosion. (auteurs)

  2. Physics of phenomena in the zone close to an underground nuclear explosion; Physique des phenomenes en zone proche des explosions nucleaires souterraines

    Energy Technology Data Exchange (ETDEWEB)

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

    1969-07-01

    After a description of the phenomenology of underground explosions, the basic laws governing the propagation in the ground of the energy produced by the explosion are given. The reports considers hydrodynamics, the mechanics of solids, the equations of state for solids and gases in the case of very high and medium pressures, and the dynamical strength of solids. These various elements make it possible to draw up a system of equations which define completely the changes with time of the shock-wave produced in the ground by the explosion. (authors) [French] Apres une description de la phenomenologie des explosions souterraines, on expose les lois fondamentales regissant la propagation dans le sol de l'energie degagee par l'explosion. L'expose comprend des developpements sur l'hydrodynamique, la mecanique des solides, les equations d'etat des solides et des gaz, aux tres fortes et moyennes pressions, et sur la resistance dynamique des solides. Ces differents elements permettent d'ecrire un systeme d'equations qui definissent completement l'evolution dans le temps de l'onde de choc emise dans le sol par l'explosion. (auteurs)

  3. Méthodes de calcul pour la conception des systèmes de protection cathodique des structures longilignes Computing Methods for Designing Cathodic Protection Systemes for Elongate Stuctures

    Directory of Open Access Journals (Sweden)

    Roche M.

    2006-11-01

    Full Text Available Les différentes structures longilignes qu'utilise l'industrie des hydrocarbures sont, dans la plupart des cas, soumises à un système de protection cathodique par anodes sacrificielles ou par courant imposé. La conception de ces systèmes doit être basée sur l'étude de la variation du potentiel et de l'intensité le long de la structure causée par la chute ohmique. La méthode classique de calcul résoud couramment le cas des structures longilignes à diamètre constant traversant un terrain dont la résistivité est considérée comme constante sur toute la longueur. Dans le cas où la constitution de la structure varie, comme celui des casings de puits de forage, ou quand celle-ci traverse plusieurs types de terrain, le problème se complique. Nous proposons une méthode générale permettant de traiter rapidement tout problème de ce type, le nombre de tronçons n'étant pas limité. Cette méthode fait appel à des notions de facteur de réflexion et de résistance équivalente déjà exposées dans la littérature mais dont l'usage ne semble pas s'être répandu. The different elongate structures used by the hydrocarbon industry are, in most cases, subjected ta a cathodic protection system consisting of sacrificial anodes or an impressed current. Desings of such systems must be boséd on an analysis of variations in the potential and intensity along the structure as the result of the ohm drop. The conventional computing method commonly solves cases of elongote structures with a constant diameter, running through ground whose resistivity is considéred to be constant over the entire length. When the~nake-up of the structure varies, as is the case for borehole casings, or when it goes through several types of formations, the problem gets more complicated. We propose a general method for quickly dealing with any problem of this type, with no limit ta the number of lengths involved. This method makes use of reflection factor and

  4. Some particular aspects of control in nuclear power reactors; Conception de la surete en france et influence des imperatifs de surete sur la conception des reacteurs

    Energy Technology Data Exchange (ETDEWEB)

    Vathaire, F de; Vernier, Ph; Pascouet, A [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1964-07-01

    This paper reviews the experience acquired in France on the question, of reactor safety. Since a special paper is being presented on reactors of the graphite gas type, the safety of the other types studied in France is discussed here: - heavy water-gas reactors, - fast neutron reactors, - water research reactors of the swimming-pool and tank types. The safety rules peculiar to the different types are explained, with emphasis on their influence on the reactor designs and on the power limits they impose. The corresponding safety studies are presented, particular stress being placed on the original work developed in these fields. Special mention is made of the experimental systems constructed for these studies: the reactor CABRI, pile loop for depressurization tests, loops outside the pile, mock-ups etc. (authors) [French] La presente communication propose une synthese de l'experience acquise en France en matiere de surete des reacteurs. Les reacteurs de la filiere graphite-gaz faisant l'objet d'une communication particuliere, on examine ici la surete des autres types de reacteurs etudies en France: - reacteurs eau lourde-gaz, - reacteurs a neutrons rapides, - reacteurs de recherche a eau des types piscines et tank. Les imperatifs de surete propres aux differentes filieres sont developpes, en mettant l'accent sur leur influence sur la conception des reacteurs et sur les limitations de puissance qu'ils entrainent. Les etudes de surete correspondantes sont presentees, en insistant plus particulierement sur les travaux originaux developpes dans ces domaines. On indique notamment les moyens d'essais qui ont ete construits pour ces etudes: le reacteur CABRI, boucle en pile pour essais de depressurisation, boucles hors pile, maquettes, etc. (auteurs)

  5. 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)

  6. Impacts of energy crop cultivation on nature and landscape. Development and application of an evaluation method; Auswirkungen des Energiepflanzenanbaus auf Natur und Landschaft. Entwicklung und Anwendung einer Bewertungsmethode

    Energy Technology Data Exchange (ETDEWEB)

    Wiehe, Julia

    2011-08-15

    For long-term planning, knowledge about the interrelationship of effects of the cultivation method and the sensitivity of ecological balance is essential. Hence, the objective of this thesis is the development of a method for the evaluation of the impacts of bioenergy crop production for biogas use on the natural environment. The developed method is in alignment with existing methods. It is also in alignment with those methods used within the practice of landscape planning, so that the method as well as the derived conclusions can be implemented into landscape planning practice in the future. The evaluation method has been applied in the three model regions Hildesheim, Soltau-Fallingbostel and Emsland. These test areas represent different physical regions in Lower Saxony and typical agricultural production conditions. On the basis of these results, general statements on the impact of bioenergy crop production on the ecological balance of the area can be made. [German] Grundlage fuer eine vorausschauende Steuerung des Ausbaus erneuerbarer Energien ist die Kenntnis der Zusammenhaenge der Wirkung des Energiepflanzenanbaus und der Empfindlichkeit des Naturhaushaltes. Ziel der Arbeit ist daher die Erarbeitung einer Methode zur umfassenden Bewertung dieser Auswirkungen auf den Naturhaushalt. Die Methode orientiert sich an bereits bestehenden und in der Praxis der Landschaftsplanung angewendeten Bewertungsmethoden, so dass sie ebenso wie die daraus abgeleiteten Schlussfolgerungen zukuenftig Eingang in die Planungspraxis finden kann. Die Bewertungsmethode wird in den drei Modellregionen Hildesheim, Soltau-Fallingbostel und Emsland angewendet, mit denen die verschiedenen Naturraeume und fuer Niedersachsen typischen landwirtschaftlichen Produktionsbedingungen abgebildet werden. Auf Grundlage dieser Ergebnisse koennen dann allgemeine Aussagen zu den Auswirkungen des Energiepflanzenanbaus auf den Naturhaushalt gemacht werden.

  7. Automation on computers of the partial area method for the analysis of 's' neutron induced resonances. I. Without interference terms. (1962); Automatisation sur ordinateur de la methode des aires partielle dans l'analyse des resonances induites par les neutrons 's'. I. sans terme d'interference. (1962)

    Energy Technology Data Exchange (ETDEWEB)

    Bianchi, G; Corge, C R [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1962-07-01

    This report deals with numerical analysis of transmission resonances induced by 's' wave neutrons in time of flight experiments. The analysis method used is the partial area one. The only case treated here, in this first part, is the one when the interference term can be neglected. Programs and subroutines are thoroughly described, which determine from experimental raw data the resonant transmission, the partial areas, and the resonance parameters. (authors) [French] Le present rapport a pour objet l'analyse numerique sur ordinateur IBM 7090, des resonances dues aux neutrons 's' dans les experiences de transmission par temps de vol, la methode d'analyse utilisee etant la methode des aires partielles. Dans cette premiere partie, seul a ete envisage le cas ou le terme d'interference peut etre neglige. On y trouvera une description detaillee des programmes et sous programmes elabores pour determiner les transmissions resonantes avec leur trace, a partir des donnees experimentales brutes, les aires partielles afferentes ainsi que les parametres caracteristiques des resonances. (auteurs)

  8. The discrete ordinate method in association with the finite-volume method in non-structured mesh; Methode des ordonnees discretes associee a la methode des volumes finis en maillage non structure

    Energy Technology Data Exchange (ETDEWEB)

    Le Dez, V; Lallemand, M [Ecole Nationale Superieure de Mecanique et d` Aerotechnique (ENSMA), 86 - Poitiers (France); Sakami, M; Charette, A [Quebec Univ., Chicoutimi, PQ (Canada). Dept. des Sciences Appliquees

    1997-12-31

    The description of an efficient method of radiant heat transfer field determination in a grey semi-transparent environment included in a 2-D polygonal cavity with surface boundaries that reflect the radiation in a purely diffusive manner is proposed, at the equilibrium and in radiation-conduction coupling situation. The technique uses simultaneously the finite-volume method in non-structured triangular mesh, the discrete ordinate method and the ray shooting method. The main mathematical developments and comparative results with the discrete ordinate method in orthogonal curvilinear coordinates are included. (J.S.) 10 refs.

  9. The discrete ordinate method in association with the finite-volume method in non-structured mesh; Methode des ordonnees discretes associee a la methode des volumes finis en maillage non structure

    Energy Technology Data Exchange (ETDEWEB)

    Le Dez, V.; Lallemand, M. [Ecole Nationale Superieure de Mecanique et d`Aerotechnique (ENSMA), 86 - Poitiers (France); Sakami, M.; Charette, A. [Quebec Univ., Chicoutimi, PQ (Canada). Dept. des Sciences Appliquees

    1996-12-31

    The description of an efficient method of radiant heat transfer field determination in a grey semi-transparent environment included in a 2-D polygonal cavity with surface boundaries that reflect the radiation in a purely diffusive manner is proposed, at the equilibrium and in radiation-conduction coupling situation. The technique uses simultaneously the finite-volume method in non-structured triangular mesh, the discrete ordinate method and the ray shooting method. The main mathematical developments and comparative results with the discrete ordinate method in orthogonal curvilinear coordinates are included. (J.S.) 10 refs.

  10. Production and use artificial radioelements in France; Production et utilisation des radioelements artificiels en France

    Energy Technology Data Exchange (ETDEWEB)

    Fisher, C; Cassin, L [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1958-07-01

    The aim of this report is to give a picture of the French accomplishment in the field of artificial radioelement production, and to review their uses up to march 31, 1958. The Commissariat a l'Energie atomique plays a major role in this work, accounting for practically the whole of the French production, centralising the imports, helping to control the distribution and contributing to research on, and development of, new applications. (author)Fren. [French] Ce rapport a pour but de presenter l'ensemble des realisations francaises dans le domaine de la production des radioelements artificiels et de faire le point, a la date du 31 mars 1958, de leur utilisation. Le Commissariat a l'Energie atomique joue un role preponderant puisqu'il assure la quasi totalite de la production francaise, centralise les importations, participe au controle de la distribution et contribue a l'etude et au developpement de nouvelles applications. (auteur)

  11. Simplified method for the determination of strontium-90 in large amounts of bone-ash; Methode simplifiee de dosage du strontium 90 sur des quantites importantes de cendres d'os

    Energy Technology Data Exchange (ETDEWEB)

    Patti, F; Jeanmaire, L [Commissariat a l' Energie Atomique, Fontenay-aux-roses (France). Centre d' Etudes Nucleaires

    1966-06-01

    The principle of the determination is based on a 3-step process: 1) concentrating the strontium by attacking the ash with nitric acid; 2) elimination of residual phosphoric ions by a double precipitation of strontium oxalate; and 3) extraction of yttrium 90, counted in the oxalate form. The advantages of the method: -) using simple techniques it makes it possible to process 50 g of ash; -) the initial concentration of strontium considerably reduces the volume of the solutions as well as the size of precipitates handled. Fuming nitric acid is used in a specially designed burette. (authors) [French] Le principe du dosage repos sur un procede en 3 etapes: 1) Concentration du strontium par une attaque nitrique des cendres; 2) Elimination des ions phosphoriques restants par une double precipitation de l'oxalate de strontium. 3) Extraction de l'yttrium 90, compte sous forme d'oxalate. Interet de la methode: dans des conditions techniques simples, elle permet le traitement de 50 g de cendres d'os; la concentration initiale du strontium reduit notablement le volume des solutions ainsi que l'importance des precipites manipules. L'acide nitrique fumant est utilise par l'intermediaire d'une burette specialement concue a cet effet.

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

    Energy Technology Data Exchange (ETDEWEB)

    Vetere, V

    2002-09-15

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

  13. Study of the propagation of fast neutrons in water, by Monte-Carlo methods; Etude de la propagation des neutrons rapides dans l'eau par des methodes de Monte-Carlo

    Energy Technology Data Exchange (ETDEWEB)

    Lafore, P; Lattes, R; Millot, J P [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1958-07-01

    We have studied the propagation in water of neutrons from mono-directional plane sources with energies ranging from 300 keV to 19,66 MeV, placed in an infinite water medium. The exact paths of a number of neutrons are determined, taking into account the microscopic sections, assuming that inelastic collisions of the neutrons on oxygen are absorptions, and neglecting the loss of energy by elastic collisions on oxygen. The neutron lifetimes have been made use of to study the propagation of neutrons from fission sources, Po-Be, Po-B and Ra-Be, as well as the reflection of fast neutrons on a semi-infinite water medium. We have taken complete account of the first collision in order to improve the precision of the results. The calculations were carried out by Mrs J. VASSEUR and Mr A. GUILLOU. (author)Fren. [French] Nous etudions la propagation dans l'eau des neutrons a partir de sources planes monodirectionnelles dont les energies sont repartis de 300 keV a 19,66 MeV, placees dans un milieu infini d'eau. Nous determinons les trajectoires exactes d'un certain nombre de neutrons en tenant compte des sections microscopiques, en supposant que les chocs inelastiques des neutrons sur l'oxygene sont des absorptions, et en negligeant la perte d'energie par chocs elastiques sur l'oxygene. Les vies de neutrons ont ete exploitees pour etudier la propagation des neutrons a partir de sources de fission, Po-Be, Po-B et Ra-Be, ainsi que la reflexion des neutrons rapides sur un milieu semi-infini d'eau. On a tenu compte integralement du premier choc pour ameliorer la precision des resultats. Les calculs ont ete effectues par Mme J. VASSEUR et M.A. GUILLOU. (auteur)

  14. Concept for urban heating systems using co-generation; Conception de systemes de chauffage urbain pour la cogeneration. Phase I: application au quartier des Morasses (Martigny) de la methode de conception des reseaux de chauffage urbain developpe au LENI. Rapport final

    Energy Technology Data Exchange (ETDEWEB)

    Cherix, G. [Centre de competence en urbistique CREM, Martigny (Switzerland); Weber, C. [Swiss Federal Institute of Technology (EPFL), Laboratoire d' energetique industrielle (LENI), Lausanne (Switzerland)

    2006-07-01

    This final report for the Swiss Federal Office of Energy (SFOE) reviews the work done in the first phase of a project concerning the concept for a district heating system in Martigny, Switzerland. This work was carried out by the Centre for Municipal and Energy Research CREM in Martigny, Switzerland, and the Laboratory for Industrial Energy LENI at the Swiss Federal Institute of Technology in Lausanne. Software developed at the LENI is introduced and its use for the determination of the necessary configuration and modes of operation of a district heating system in Martigny is discussed. The situation in the Morasses district of Martigny and the promising results obtained are looked at. These can lead to the optimisation of heating supply in other such areas.

  15. An attempt at determining Des of glacial sediments using different luminescence methods

    International Nuclear Information System (INIS)

    Ou Xianjiao; Lai Zhongping; Zeng Lanhua

    2013-01-01

    Background: Absolute dating is the key technical issue of Quaternary glacial research. Optically stimulated luminescence (OSL) has been increasingly applied to Quaternary glacial dating in recent years. However, problems such as insufficient bleaching, low luminescence sensitivity, high thermal transfer effect, etc, still remain. Purpose: In order to investigate the applicability of equivalent dose (D e ) determination of glacial sediments by different OSL methods, six samples were collected from the Yingpu Valley of eastern Qinghai-Tibetan Plateau (two samples from modern glacial sediments, three from moraines and glacial terrace attributed to Neoglacial and one from a moraine attributed to the last glaciation). Methods: The D e s were determined by SAR combined SGC technique, using three methods: quartz large aliquot (6 mm) BSL, small aliquot (2/3 mm) BSL and polymineral IRSL. Results: D e s determined by SGC are consistent with D e s determined by SAR protocol. Comparison of three methods shows that IRSL D e >large aliquot BSL D e >small aliquot BSL D e . D e s of polymineral IRSL are obviously higher than quartz BSL. Conclusions: It is obviously that feldspar is more difficult to reset than quartz, thus is not suitable for dating glacial sediments in this region. Quartz large aliquot method is suitable for well bleached glacial samples. Due to the low luminescence sensitivity of quartz, small aliquot method showed poor luminescence characteristics. Moreover, this method cannot distinguish the poor bleached grains in this measurement. However, it is possible that quartz small aliquot, even single grain method could be used to date older or brighter glacial samples. More works are required to solve the problems we have encountered in dating low sensitivity glacial sediments. (authors)

  16. Operation safety of control systems. Principles and methods; Surete de fonctionnement des systemes de commande. Principes et methodes

    Energy Technology Data Exchange (ETDEWEB)

    Aubry, J.F. [Institut National Polytechnique, 54 - Nancy (France); Chatelet, E. [Universite de Technologie de Troyes, 10 (France)

    2008-09-15

    This article presents the main operation safety methods that can be implemented to design safe control systems taking into account the behaviour of the different components with each other (binary 'operation/failure' behaviours, non-consistent behaviours and 'hidden' failures, dynamical behaviours and temporal aspects etc). To take into account these different behaviours, advanced qualitative and quantitative methods have to be used which are described in this article: 1 - qualitative methods of analysis: functional analysis, preliminary risk analysis, failure mode and failure effects analyses; 2 - quantitative study of systems operation safety: binary representation models, state space-based methods, event space-based methods; 3 - application to the design of control systems: safe specifications of a control system, qualitative analysis of operation safety, quantitative analysis, example of application; 4 - conclusion. (J.S.)

  17. Analytical representation of time correlation functions and application to relaxation problems; Representation analytique des fonctions de correlation temporelle et application a des problemes de relaxation

    Energy Technology Data Exchange (ETDEWEB)

    Dupuis, M [Commissariat a l' Energie Atomique, 91 - Saclay (France). Centre d' Etudes Nucleaires, departement de physico-chimie, services des isotopes stables

    1971-07-01

    Two analytical representations of the Laplace transform of the time autocorrelation of a dynamical variable, namely the moment expansion and Mori's continued fraction expansion, are investigated from the point of view of structure and convergence properties, and the relation between them is established. The general theory is applied first to a dynamical model exactly solvable, the isotopic impurity in a linear chain of coupled harmonic oscillators, and then to two stochastic models recently introduced by Gordon for the rotational diffusion of molecules. In the latter case, the continued fraction expansion yields simple analytical expressions for the infrared absorption band shapes, showing that these models contain all the features of observed shapes in compressed gases, liquids and solutions. (author) [French] Deux representations analytiques de la transformee de Laplace de la fonction d'autocorrelation temporelle d'une variable dynamique, le developpement en moments et le developpement en fraction continue recemment introduit par Mori, sont etudiees du point de vue de leurs proprietes de structure et de convergence, en meme temps que la relation qui existe entre elles est etablie. La theorie generale est appliquee, d'une part, a un modele dynamique exactement soluble, celui d'une particule isotopique dans une chaine lineaire d'oscillateurs harmoniques couples, et, d'autre part, a deux modeles stochastiques recemment proposes par Gordon pour la diffusion rotationnelle des molecules. Dans ce dernier cas, la voie de la fraction continue fournit des expressions analytiques simples pour les formes de bande d'absorption infrarouge, montrant que ces modeles possedent les caracteristiques des formes observees dans les gaz comprimes, les liquides ou les solutions. (auteur)

  18. A sensitive method for the detection of tritium-marked {beta}-indolylacetic acid in plant cells and tissues at physiological and experimental concentrations (1962); Une methode sensible pour la detection de l'acide {beta}-indolylacetique marque au tritium, dans des cellules et tissus vegetaux a des concentrations physiologiques et experimentales (1962)

    Energy Technology Data Exchange (ETDEWEB)

    Figier, J; Khau Van Kien, L; Roux, E [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1962-07-01

    The localisation of {beta}-indolylacetic acid (A.I.A.), a growth auxin is attempted using nuclear indicators ({sup 14}C and tritium). The radio - auto-histographic detection method depends on the insolubilization of A.I.A. 'in situ' by picric acid and basic lead acetate at a suitable pH, the A.I.A. being protected from histological solvents. The results of the detections corresponding to physiological responses during growth tests on Pisum, Avena, Phascolus and Vicia, at concentrations of 10{sup -5} and higher make possible the localisation of tissues in agreement with the auxinic activity and with the relations already known between A.L.A. and cellular formations. By increasing the time of exposures of the sections, it will be possible to attain concentrations which are much lower and more clearly physiological. (authors) [French] La localisation de l'acide {beta}-indolylacetique (A.L.A.), auxine de croissance est abordee avec les indicateurs nucleaires ({sup 14}C et tritium). La methode de detection radio-autohistographique repose sur l'insolubilisation de l'A.I.A. 'in situ' par l'acide picrique et l'acetate basique de plomb a pH convenable, le mettant a l'abri des solvants histologiques. Les resultats des detections correspondant a des reponses physiologiques au cours de test de croissance sur Pisum, Avena, Phascolus et Vicia, a la concentration de 10{sup -5} et plus elevee permettent des localisations tissulaires concordant avec l'activite auxinique et les rapports deja connus de l'A.I.A. avec les formations cellulaires. En prolongeant la duree d'exposition des coupes, il sera possible de descendre a des concentrations bien plus faibles et plus nettement physiologiques. (auteurs)

  19. Berechnung des Hochfrequenzverhaltens komplexer Strukturen mit der Methode gekoppelter Streuparameter – CSC

    Directory of Open Access Journals (Sweden)

    H.-W. Glock

    2004-01-01

    Full Text Available Es wird eine Methode zur Berechnung der Hochfrequenz-Eigenschaften komplexer Strukturen vorgestellt. Das Verfahren beruht auf der Zerlegung der Gesamtstruktur in einzelne einfachere Segmente, deren breitbandige S-Matrizen mit kommerziellen Programmen berechnet werden. Das Gesamtsystem kann von beliebiger Topologie sein, und die Zahl der die Segmente verkoppelnden Hohlleiter- Moden ist nicht begrenzt. Als Ergebnis steht bei offenen Strukturen deren vollständige S-Matrix, bei abgeschlossenen deren Resonanzeigenschaften zur Verfügung. Die theoretischen Grundlagen werden beschrieben und die Anwendung mit Beispielen aus dem Gebiet der Teilchenbeschleuniger und zu Eigenschaften schwach elliptisch geformter Resonatoren illustriert. A method called Coupled S-Parameter Calculation – CSC is described which is used to calculate the rf properties of complex structures, i.e. either their scattering (devices with ports or their resonance properties. The method is based on the segmentation of the entire system into sections being less complex, the external calculation of the section’s broadband S-matrices, and a combination scheme, which is applicable to any topology and number of modes. The method’s principle is described. Examples from the field of particle accelerator cavities and about the properties of weakly elliptical resonators are given.

  20. Methode des Rayons avec Calcul d’Intensite Appliquee a la Propagation Anormale (Method of Ray Intensity Calculation as Applied to Anomalous Propagation),

    Science.gov (United States)

    1986-06-01

    plus rapproch~es. Cette question, qui constitue en elle-mgme un domaine de recherche, d~ borde du cadre du present rapport. * Il est possible d’gtendre...par la commande JCL "PROPEX:T.’ qui produit le module ex~cutable "PROPAG:EX". TABLEAU I Bloc principal PROPAK *NOM DES ROUTINES FONCTION PROPAG...alise la r &mission des rayons r~fl~chis e77 SANS CLASSIFICATION 22 TABLEAU II Bloc utilitaire UTILPAK NOM DES ROUTINES FONCTION H - Calcule r la

  1. Effects of Radiation on Germ Cells of Insects: Dominant Lethals, Gamete Inactivation and Gonial-Cell Killing; Effets des rayonnements sur les cellules germinales des insectes: letalite dominante, inactivation des gametes et destruction des cellules des gonades; Vozdejstvie radiatsii na polovye kletki nasekomykh: dominantnye letali, inaktivatsiya gamet i umershchvlenie polovykh kletok; Efectos de las radiaciones sobre las celulas germinales de los insectos: elementos letales dominantes, inactivacion de los gametos y exterminacion de las celulas gonadicas

    Energy Technology Data Exchange (ETDEWEB)

    Von Borstel, R. C. [Biology Division, Oak Ridge National Laboratory, Oak Ridge, TN (United States)

    1963-09-15

    : par l'un des modes d'induction d'une letalite dominante, par l'inactivation directe d'une fonction et par des manieres genetiquement indefinissable, liees ou non a la letalite dominante. Les agents chimiques de mutation paraissent egalement provoquer un accroissement curieux du pouvoir fertilisant du sperme. La radiosensibilite varie avec les divers stades de l'oogenese et de la spermatogenese; certaines cellules passent par des stades au cours desquels leur radiosensibilite peut varier dans un rapport de 1 a 50. Des comparaisons entre des diptetes, des hymenopteres et des coleopteres ont revele une similarite frappante dans la maniere dont ces especes reagissent aux rayonnements, tant en ce qui concerne la sensibilite aux divers stades de developpement que l'intensite de la reaction en fonction de la dose. Le ver a soie Bombyx mori (lepidoptere) semble avoir beaucoup de points communs avec les representants des autres ordres en ce qui concerne l'effet des rayonnements sur les cellules germinales, mais il en differe nettement pour ce qui est des facteurs letaux dominants induits. Les especes presentant des mecanismes genetiques anormaux (par exemple, le Planococcus citri, coccide hemiptere) constituent des cas particuliers et ils reagissent aux rayonnements de facon tres differente des autres especes. Dans la lutte contre les insectes par la methode de Tirradiation des males, la letalite dominante est aussi efficace pour les especes ou l'accouplement a lieu plusieurs fois que pour celles ou il a lieu une seule fois. On peut considerer l'inactivation du sperme et la destruction des cellules des gonades comme des facteurs de sterilite reelle; leur efficacite est maximum chez les especes ou l'accouplement n'a lieu qu'une seule fois. Pour le controle le plus efficace, il faudrait avoir recours a des doses provoquant la letalite dominante maximum, l'inactivation minimum du sperme et la destruction totale des cellules des gonades. Il est facile de determiner ces parametres

  2. Comparison of methods for measuring the ion exchange capacity of a soil. Development of a quick method; Comparaison des methodes de mesure de la capacite d'echange d'ions d'un sol. Mise au point d'une methode rapide

    Energy Technology Data Exchange (ETDEWEB)

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

    1959-07-01

    In the course of a study on the movement of radioactive ions in soil we had to measure the cationic exchange capacity of various soil samples, this parameter being one of the most important in the appreciation of the extent of fixation of radioactive ions in the ground. The object of this report is to describe the various methods used and to compare the results obtained. A colorimetric method, using Co(NH{sub 3}){sub 6}{sup 3+} as exchangeable ion, was developed. It gives results comparable to those obtained with conventional methods, whilst considerably reducing the time necessary for the operations. (author) [French] A l'occasion de l'etude du mouvement des ions radio-actifs dans un sol, nous avons ete amenes a mesurer la capacite d'echange cationique de differents echantillons de sols; ce parametre etant un des plus importants pour apprecier la valeur de la fixation des ions radioactifs dans un terrain. L'objet de ce rapport est d'exposer les diverses methodes utilisees et de comparer les resultats obtenus. Une methode calorimetrique, utilisant Co(NH{sub 3}){sub 6}{sup 3+} comme ion echangeable, a ete mise au point: elle donne des resultats comparables a ceux obtenus avec les methodes habituelles et permet de reduire considerablement la duree des manipulations. (auteur)

  3. Contribution a l'auscultation des chaussees mixtes par methodes GPR et electrique

    Science.gov (United States)

    Kaouane, Carole

    Quebec's infrastructures are ageing. A reliable, quick and economical assessment of the state of urban roads would help to plan civil engineering. This M.Sc. thesis aims to investigate and develop the potential of Ground Penetrating Radar (GPR) and electrical methods to assess pavement condition subject to wetting, freezing and drying cycles. The objectives are to display defects and estimate water content in the materials used for the mixed pavement construction; these consist in layers of asphalt (top), concrete (middle) and grade and sub-grade (bottom). Prior studies showed a valuable potential of joint application of GPR and electrical resistivity to assess mixed pavement condition. These studies were mainly based on numerical modeling and some site tests using both methods. It was concluded that a better evaluation of the potential of the coupled methods would come from the assessment of physical properties and validation from geotechnical evidences. At first, we characterized the context. Structural defects and water content implied modification of physical properties of road materials. After running numerical modeling, we carried out an experiment in one of the streets in Montreal (Canada) where pavement needed complete rehabilitation. GPR surveys were carried out before the pavement was destroyed and removed, and subsequently a resistivity imaging was carried out on the subgrade layer. We also sampled blocks of asphalt and concrete along the street from the demolition rubble in order to study their physical properties in the lab. Soil samples were taken from trenches to measure water content. The grade and sub-grade were mainly a mix of clayey-silt and gravel, as the embedding ground is grey clay. We measured the complex dielectric constants of asphalt and concrete in the range 50 MHz-900 MHz with a recently developed dielectric probe sampling a volume of 30 cm3. Resistivity measurements were also performed on large cores of asphalt and concrete using an

  4. Forecasting the Quantity and Activity of Fission Products in France in Future Years in the Light of Atomic Energy Development; Quantite et Activite des Produits de Fission Obtenus en France dans les Annees a Venir Compte Tenu du Developpement de l'Energie Atomique; 041a 041e 041b 0414 ; Cantidad y Actividad de los Productos de Fision que se Obtendran en Francia en los Anos Venideros, Habida Cuenta del Desarrollo de la Energia Atomica

    Energy Technology Data Exchange (ETDEWEB)

    Guirlet, J.; Lavie, J. M. [Commissariat a l' Energie Atomique, Saclay (France)

    1960-07-01

    With the aid of Wigner and Way's formula it is possible to predict theoretically the activity of the complex mixture of fission products originating in a reactor. Account is taken in the study of prospective nuclear power production in France up to 1975. It is assumed that the uranium stays in the reactor for periods of three and of six months. It is also possible to determine the activity of a given fission product and to calculate its decay time. The substance selected was strontium for an activation period of three months. Each group of curves shows total activity at any moment and the activity of particular fission products over a given period. (author) [French] En utilisant la formule de Wigner et Way, il est possible de prevoir theoriquement l'activite du melange complexe de produits de fission provenant d'une pile. L'etude a ete faite en tenant compte de previsions en ce qui concerne en France la production d'electricite d'origine atomique jusqu'en 1975. On a suppose des temps de sejour en pile de l'uranium de trois mois et de six mois. Il est possible egalement de trouver l'activite d'un produit de fission particulier, et de donner sa decroissance. Le corps choisi est le strontium pour un temps d'activation de trois mois. Chaque ensemble de courbes donne a tout instant l'activite totale, et l'activite propre des produits de fission correspondant a une periode donnee. (author) [Spanish] Empleando la formula de Wigner y Way se puede calcular teoricamente la actividad de la mezcla compleja de productos de fision procedentes de una pila. Para esta memoria se han tenido en cuenta las previsiones de produccion de electricidad nucleoelectrica en Francia hasta 1975. Los autores suponen que el uranio permanece tres o seis meses en la pila y han conseguido determinar la actividad de un producto de fision determinado, asi como su periodo de desintegracion. Han escogido el estroncio, con un tiempo de activacion de 3 meses. Cada conjunto de curvas da la actividad total

  5. A method based on a separation of variables in magnetohydrodynamics (MHD); Une methode de separation des variables en magnetohydrodynamique

    Energy Technology Data Exchange (ETDEWEB)

    Cessenat, M.; Genta, P.

    1996-12-31

    We use a method based on a separation of variables for solving a system of first order partial differential equations, in a very simple modelling of MHD. The method consists in introducing three unknown variables {phi}1, {phi}2, {phi}3 in addition of the time variable {tau} and then searching a solution which is separated with respect to {phi}1 and {tau} only. This is allowed by a very simple relation, called a `metric separation equation`, which governs the type of solutions with respect to time. The families of solutions for the system of equations thus obtained, correspond to a radial evolution of the fluid. Solving the MHD equations is then reduced to find the transverse component H{sub {Sigma}} of the magnetic field on the unit sphere {Sigma} by solving a non linear partial differential equation on {Sigma}. Thus we generalize ideas due to Courant-Friedrichs and to Sedov on dimensional analysis and self-similar solutions. (authors).

  6. Wastes behavior and environmental impacts, researches and methods; Comportement des dechets et impacts environnementaux, recherches et methodes

    Energy Technology Data Exchange (ETDEWEB)

    Labeyrie, J; Chateau, L [Agence de l' Environnement et de la Maitrise de l' Energie, (ADEME), 49 - Angers (France); Gin, St [CEA/VALRHO - site de Marcoule, Dept. de Recherche en Retraitement et en Vitrification DRRV, 30 - Marcoule (France); and others

    2001-07-01

    The wastes management policy takes into account more and more often the environmental impacts mastership. This evolution is particularly appreciable when the wastes directly interact with the environment: storage, utilization for roads construction and so on. In this context the ADEME organized the 8 june 2000 a colloquium to present the new evaluation methods and tools, to describe the regulations and to identify the research programs needed for this environmental policy. Eleven papers are presented. (A.L.B.)

  7. Methode unifiee de simulation et de conception des convertisseurs de puissance

    Science.gov (United States)

    Fortin Blanchette, Handy

    High frequency power converters are now master piece in emerging new renewable energy applications such as hybrid vehicules. These new technologies merge the power of electrical machine with the thermal motor power. The power converters used to control those electrical machines are embeded technologies with high efficiency conversion and a high reliability. More than ground vehicule applications, embeded power converters are now present in aeronautic and aerospace domains. In this sense, high reliability and high efficiency are now important characteristics that are not only suitable but needed. In spite of this progression, power converters development remains today a complex science. Even if advanced complex techniques are now available to increase the converter stability, there are no systemic rules to design the converter physical assembly. Very often, an artistic approach is used to place the components inside the converter in the more convenient places. This lack of rigor about EMI problems is not so surprising because this kind of analysis is costly and risky. In general, to solve this type of problems, one designs a second and a third printed circuit generation which is not necessarily a quick and systematic approach. To overcome these difficulties, the main goal of this thesis is to provide simple and improved tools for power converter circuit designers. The key point are to solve EMI and reliability problems at the earlier design stage and not during the prototyping phase. Many solutions are exposed in this text about the magnetic field orientation, leakage inductances identification, power semiconductors modeling and electromagnetic modeling of power converters. The exactness of these methods is proved by using it to develop a matrix converter. The printed circuits are designed to orient properly the magnetic field enabling to introduce low power sensing circuits directly inside the converter. This application is one of the numerous possibilities offered

  8. Evaluation des méthodes chimiques, spectroscopiques et chromatographiques utilisables pour l'identification des polluants pétroliers en mer Evaluation of Chemical, Spectroscopic and Chromatographic Methods Used to Identify Offshore Oil Pollutants

    Directory of Open Access Journals (Sweden)

    Albaigés J.

    2006-11-01

    Full Text Available Dans cet article on passe en revue les différentes méthodes utilisables pour l'identification des principaux polluants pétroliers de la mer par l'analyse quantitativé de leurs « marqueurs passifs x (soufre, azote, nickel, vanadium, paraffine et asphaltènes et la détermination d'autres caractéristiques intrinsèques. II s'agit de méthodes chimiques, spectroscop iques (infrarouge, ultraviolette et chromatographiques (chromatographie en phase gazeuse à haute résolution avec détection par ionisation de flamme, photométrie de flamme et capture d'électrons. Les mesures ont concerné une grande variété de produits susceptibles de polluer la côte méditerranéenne espagnole - pétrole brut des gisements offshore d'Amposta et de Castellôn; - pétroles bruts importés traités dans les raffineries côtières (Boscan, Es Sider, Kuwait, Arabian light, etc.; - fractions lourdes provenant de ces raffineries (fuel-cils, asphaltes, lubrifiants; - polluants réels; - échantillons altérés artificiellement en laboratoire afin de mettre en évidence l'action progressive des éléments naturels. On a trouvé que les méthodes les plus intéressantes étaient : - le dosage chimique du soufre, du nickel et du vanadium; - la spectroscopie infrarouge; - la chromatographie en phase gazeuse à haute résolution avec détection par ionisation et photométrie de flamme. This article reviews the different methods that con be used to identify the leading petroleum pollutants of the sea by quantitative analysis of their a passive markers » (sulfur, nitrogen, nickel, vanadium, paraffin, asphaltenes and by determining other intrinsic properties. These methods are chemical, spectroscopic (infrared, ultraviolet and chromatographic (high-resolution gas chromatography with flame ionization detection, flame photometry and electron capture. Measurements were made of a great variety of products capable of polluting the Spanish Mediterranean coast, including

  9. Optimization of refinery operations when uncertainty exists: Algeria's case; Optimisation des operations du raffinage en presence d'incertitudes: Cas de l'Algerie

    Energy Technology Data Exchange (ETDEWEB)

    Benyoucef, Abderrezak; Lantz, Frederic

    2010-09-15

    The objective of this article is to analyze the development of Algeria refinery industry when uncertainty exists, from a dynamic linear programming model. Because of the different market conditions volatility, many parameters must be able to be considered as uncertain. In our study, we treat mainly uncertainties of petroleum products demand. The model gives production levels, the units market rate and the exterior exchange of products at horizons 2030. It allows to appreciate the impact of volatility on this industry's development. [French] L'objectif de cet article est d'analyser le developpement de l'industrie algerienne du raffinage en presence d'incertitudes, a partir d'un modele de programmation lineaire dynamique. En raison de la volatilite des differentes conditions du marche, de nombreux parametres doivent pouvoir etre consideres comme incertains. Dans notre etude, nous traitons en particulier des incertitudes sur la demande des produits petroliers. Le modele fournit les niveaux de production, le taux de marche des unites et les echanges exterieurs de produits a l'horizon 2030. Il permet ainsi d'apprecier l'impact de la volatilite sur le developpement de cette industrie.

  10. Aufbau einer Methode zum Nachweis von Protein-Protein-Interaktionen ausgewählter Bereiche des Riesenmoleküls Titin

    OpenAIRE

    Schiffer, Kai

    2017-01-01

    Titin ist das größte in Säugetieren bekannte Protein und fungiert als molekulare Feder. Neben seinen mechanischen Eigenschaften wird Titin auch als Mechanosensor diskutiert. Ziel dieser Arbeit war es, neuartige Protein-Protein Interaktionen des Titin am Übergang zur Z-Scheibe zur I-Bande zu detektieren. Als Methode wurde zunächst der Yeast Two-Hybrid Screen verwendet. Nach Etablierung der Methode wurden potentielle Interaktoren in einem weiteren Hefeinteraktionstest überprüft. In zwei methodi...

  11. Simulation of land use evolution by discrete events method: Application to “la chaîne des puys” from XV to XVIII Century

    OpenAIRE

    Y. Michelin; C. Poix

    1998-01-01

    By using a discrete event method, simulation of land use evolution has been applied to a landscape model of “la ChaÎne des Puys” (French Massif Central) during along period (XV–XVIII centuries). The indications concerning the evolution of land use are in conformity with the observation of actual situations but the dynamic changes are faster than in actual facts. In spite of limitations due to necessary simplifications, it is now established that the discrete event method is efficient to simu...

  12. Monte-Carlo method for studying the slowing down of neutrons in a thin plate of hydrogenated matter; Methode de Monte-Carlo pour l'etude du ralentissement des neutrons dans une plaque mince de matiere hydrogenee

    Energy Technology Data Exchange (ETDEWEB)

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

    1965-07-01

    The studies of interaction of slow neutrons with atomic nuclei by means of the time of flight methods are made with a pulsed neutron source with a broad energy spectrum. The measurement accuracy needs a high intensity and an output time as short as possible and well defined. If the neutrons source is a target bombarded by the beam of a pulsed accelerator, it is usually required to slow down the neutrons to obtain a sufficient intensity at low energies. The purpose of the Monte-Carlo method which is described in this paper is to study the slowing down properties, mainly the intensity and the output time distribution of the slowed-down neutrons. The choice of the method and parameters studied is explained as well as the principles, some calculations and the program organization. A few results given as examples were obtained in the line of this program, the limits of which are principally due to simplifying physical hypotheses. (author) [French] l'etude de l'interaction des neutrons lents avec les noyaux atomiques par la methode du temps de vol s'effectue avec une source pulsee de neutrons dont le spectre en energie est assez etendu. La precision des mesures demande que la source soit intense et que la duree d'emission des neutrons soit breve et bien definie. Si la source est une cible bombardee par le faisceau de particules d'un accelerateur pulse, il est generalement indispensable de ralentir les neutrons pour avoir une intensite suffisante a basse energie. Nous presentons ici une methode de Monte-Carlo pour l'etude detaillee de ce ralentissement, notamment l'intensite et la distribution des temps de sortie des neutrons ralentis. Cette presentation comprend: la justification du choix de la methode de Monte-Carlo, les principes generaux, les differentes etapes du calcul et du programme ecrit pour le calculateur electronique IBM 7090. Nous indiquons aussi les restrictions qui sont apportees au domaine d'application de ce programme et qui proviennent surtout des

  13. Application of the pulsed neutron technique on the reactors ALIZE - AQUILON (1963); Application de la methode des neutrons pulses sur les piles ALIZE et AQUILON (1963)

    Energy Technology Data Exchange (ETDEWEB)

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

    1963-07-01

    Different methods of measuring the ratio effective delayed fraction / prompt neutron lifetime, {alpha}{sub c}, are described. According to the classic pulsed neutron technique the negative reactivity due to a localized absorber is given by {rho} / {beta}{sub eff} = {alpha} / {alpha}{sub c} -1 Experiments are reported which show that in this case {alpha}{sub c} can not be considered constant for large reactivities. The absorber element distorts the flux in the system, increasing the importance of the reflector. An application of the pulsed neutron method to the measurement of critical distributed boron concentrations of various absorber elements is described. Less time is required than for the usual super-critical techniques, and the experimental analysis is simplified. It is interesting to note that the results are not influenced by the spectral sensitivity of the control element. A modified pulsed neutron method has been tried out. This procedure was used to determine by measurements at sub-critical the critical water level of uranium-heavy water lattices with a high precision. (author) [French] Differents modes operatoires pour definir la valeur du rapport pourcentage effectif de neutrons retardes / temps de vie, {alpha}{sub c}, sont exposes. La methode classique par neutrons pulses definit l'anti-reactivite d'un element absorbant a partir de la relation: {rho} / {beta}{sub eff} {alpha} / {alpha}{sub c} -1 Les manipulations effectuees montrent qu'on ne peut considerer dans ce cas {alpha}{sub c} constant pour de tres grandes anti-reactivites. L'absorbant introduit dans la pile deforme le flux et augmente l'importance du reflecteur. Une application de la methode des neutrons pulses pour mesurer le titre critique en mg de B/l de divers absorbants est signalee. Les operations sont effectuees en regime sous-critique avec un certain gain de temps et une grande facilite de depouillement. Il est interessant de noter que les resultats ne sont pas

  14. Application of the pulsed neutron technique on the reactors ALIZE - AQUILON (1963); Application de la methode des neutrons pulses sur les piles ALIZE et AQUILON (1963)

    Energy Technology Data Exchange (ETDEWEB)

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

    1963-07-01

    Different methods of measuring the ratio effective delayed fraction / prompt neutron lifetime, {alpha}{sub c}, are described. According to the classic pulsed neutron technique the negative reactivity due to a localized absorber is given by {rho} / {beta}{sub eff} = {alpha} / {alpha}{sub c} -1 Experiments are reported which show that in this case {alpha}{sub c} can not be considered constant for large reactivities. The absorber element distorts the flux in the system, increasing the importance of the reflector. An application of the pulsed neutron method to the measurement of critical distributed boron concentrations of various absorber elements is described. Less time is required than for the usual super-critical techniques, and the experimental analysis is simplified. It is interesting to note that the results are not influenced by the spectral sensitivity of the control element. A modified pulsed neutron method has been tried out. This procedure was used to determine by measurements at sub-critical the critical water level of uranium-heavy water lattices with a high precision. (author) [French] Differents modes operatoires pour definir la valeur du rapport pourcentage effectif de neutrons retardes / temps de vie, {alpha}{sub c}, sont exposes. La methode classique par neutrons pulses definit l'anti-reactivite d'un element absorbant a partir de la relation: {rho} / {beta}{sub eff} {alpha} / {alpha}{sub c} -1 Les manipulations effectuees montrent qu'on ne peut considerer dans ce cas {alpha}{sub c} constant pour de tres grandes anti-reactivites. L'absorbant introduit dans la pile deforme le flux et augmente l'importance du reflecteur. Une application de la methode des neutrons pulses pour mesurer le titre critique en mg de B/l de divers absorbants est signalee. Les operations sont effectuees en regime sous-critique avec un certain gain de temps et une grande facilite de depouillement. Il est interessant de noter que les resultats ne sont pas affectes par la

  15. Research and Development of Ram/Scramjets and Turboramjets in Russia (La Recherche et le Developpement des Statoreacteurs, des Statoreacteurs a Combustion Supersonique et des Turbostatoreacteurs en Russie)

    Science.gov (United States)

    1993-12-01

    SCRJ - scramjet; SCRJ-R - scram-rocket engine; SFC - specific fuel consumption; SPRR - solid propellant ramrocket; SR - solid rocket; SSTO - Single...for hypersonic vehicles and aerospace planes in particular for SSTO . In the Fig. 1.20 are shown some results of study of two SSTO vehicle concepts...UI ATR ♦ RJ ♦ LA MVUMO MO^IUION VtMCU Fig.-1.20. Mast «fflcltncy of SSTO [11], M««-iif • •N>ir M>0-4|>«-M-JII-iii m-a-**-#-m-v Fig. 1.21

  16. Etude theorique et experimentale des evaporateurs de dioxyde de carbone operant dans des conditions de givrage

    Science.gov (United States)

    Bendaoud, Adlane Larbi

    Les evaporateurs de refrigeration sont surtout du type tube a ailettes, appeles serpentins, et fonctionnent dans l'une des conditions suivantes: seche, humide ou avec formation de givre. Il a ete demontre que la formation du givre sur la paroi exterieure de l'echangeur engendre une surconsommation energetique a cause des operations de degivrage puisque 15 a 20% seulement de la chaleur produite sert au degivrage tandis que le reste est dissipee dans l'environnement [1]. Avec l'avenement des nouveaux refrigerants, moins nocifs envers l'environnement, l'industrie du froid se trouve penalisee du fait que peu ou pas de composantes mecaniques (compresseur, pompe, echangeur...etc.) adaptees sont disponibles [3]. Il s'agit pour la communaute des frigoristes de combler ce retard technologique en redeveloppant ces composantes mecaniques afin qu'elles soient adaptees aux nouveaux refrigerants. Dans cette optique, et afin de mieux comprendre le comportement thermique des evaporateurs au CO2 fonctionnant dans des conditions seches, qu'un groupe de chercheurs du CanmetENERGIE avaient lance, en 2000, un programme de R & D. Dans le cadre de programme un outil de simulation des evaporateurs au CO2 a ete developpe et un banc d'essai contenant une boucle secondaire de refrigeration utilisant le CO2 comme refrigerant a ete construit. Comme continuite de ce travail de recherche, en 2006 ce meme groupe de recherche a lance un nouveau projet qui consiste a faire une etude theorique et experimentale des evaporateurs au CO2 operants dans des conditions de givrage. Et, c'est exactement dans le cadre de ce projet que se positionne ce travail de these. Ce travail de recherche a ete entrepris pour mieux comprendre le comportement thermique et hydrodynamique des serpentins fonctionnant dans des conditions de givrage, l'effet des circuits de refrigerant ainsi que celui des parametres geometriques et d'operation. Pour cela, un travail theorique supporte par une etude experimentale a ete effectue

  17. Detection of contamination of the respiratory tracts by autoradiography of sputum (1963); Recherche de contaminations des voies respiratoires par l'autoradiographie des crachats (1963)

    Energy Technology Data Exchange (ETDEWEB)

    Andre, M; Hugot, G [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1963-07-01

    The sputum collected in the morning immediately after awakening is dissolved in mineral acids and then evaporated on a stainless steel plate. It is placed in contact with a nuclear emulsion plate and the number of traces appearing after 24 hrs, 48 hrs and 7 days exposure is counted. The conditions of exposure, development, and result interpretation are defined. (authors) [French] Le crachat recueilli le matin aussitot apres le reveil est mineralise puis evapore sur une plaque d'acier inoxydable. On met en contact avec une plaque d'emulsion nucleaire et on compte le nombre de traces apparues apres 24 h, 48 h et 7 jours d'exposition. Les conditions d'exposition, de developpement et l'interpretation des resultats sont definies. (auteurs)

  18. From the coupling between ion beam analysis techniques and physico-chemical characterization methods to the study of irradiation effects on materials behaviour; Du couplage des techniques d'analyse par faisceaux d'ions et des methodes de caracterisation physico-chimique a l'etude des effets d'irradiation sur le comportement des materiaux

    Energy Technology Data Exchange (ETDEWEB)

    Millard-Pinard, N

    2003-07-01

    The general purpose of my research work is to follow and to interpret the surface evolution of materials, which have received several treatments. During my PhD and my post-doc work, my field of research was tribology. Since I arrived in the 'Aval du Cycle Electronucleaire' group of the Institut de Physique Nucleaire de Lyon, my research activities are in line with the CNRS program 'PACE ' (Programme sur l'Aval du Cycle Electronucleaire) within the ACTINET network. They are coordinated by the PARIS (Physico-chimie des actinides et autres radioelements en solution et aux interfaces) and NOMADE (NOuveaux MAteriaux pour les DEchets) GDR with ANDRA (Agence Nationale pour la gestion des Dechets RAdioactifs), EDF and IRSN (Institut de Radioprotection et de Surete Nucleaire) as partner organisations. My work focused on the study of fission products and actinides migration in barrier materials, which may be capable of assuring the long term safety of deep geological repositories. Until now, it was necessary to use the coupling of ion beam analysis techniques and physico-chemical characterization techniques. During the last few months, I have became interested in understanding radiolytic effects. This new orientation has led us to use ion beams as an irradiating tool. These irradiation experiments are pursued in three major projects. The study of cobalt sulfide inhibition effects of radiolysis gas production during the irradiation of model organic molecules. This is a collaboration with the IRSN, the Institut de Recherche sur la Catalyse and the Ecole Nationale Superieure des Mines de Saint-Etienne. A PhD, co-directed by M. Pijolat from ENSMSE and myself, concerning this study will start in October 2003. Water radiolysis effects on iron corrosion are also studied in the particular case of vitrified nuclear waste containers, which will be stored in deep geological repositories. One ANDRA financed PhD, co-directed by Nathalie Moncoffre and myself, is dedicated to this study

  19. From the coupling between ion beam analysis techniques and physico-chemical characterization methods to the study of irradiation effects on materials behaviour; Du couplage des techniques d'analyse par faisceaux d'ions et des methodes de caracterisation physico-chimique a l'etude des effets d'irradiation sur le comportement des materiaux

    Energy Technology Data Exchange (ETDEWEB)

    Millard-Pinard, N

    2003-07-01

    The general purpose of my research work is to follow and to interpret the surface evolution of materials, which have received several treatments. During my PhD and my post-doc work, my field of research was tribology. Since I arrived in the 'Aval du Cycle Electronucleaire' group of the Institut de Physique Nucleaire de Lyon, my research activities are in line with the CNRS program 'PACE ' (Programme sur l'Aval du Cycle Electronucleaire) within the ACTINET network. They are coordinated by the PARIS (Physico-chimie des actinides et autres radioelements en solution et aux interfaces) and NOMADE (NOuveaux MAteriaux pour les DEchets) GDR with ANDRA (Agence Nationale pour la gestion des Dechets RAdioactifs), EDF and IRSN (Institut de Radioprotection et de Surete Nucleaire) as partner organisations. My work focused on the study of fission products and actinides migration in barrier materials, which may be capable of assuring the long term safety of deep geological repositories. Until now, it was necessary to use the coupling of ion beam analysis techniques and physico-chemical characterization techniques. During the last few months, I have became interested in understanding radiolytic effects. This new orientation has led us to use ion beams as an irradiating tool. These irradiation experiments are pursued in three major projects. The study of cobalt sulfide inhibition effects of radiolysis gas production during the irradiation of model organic molecules. This is a collaboration with the IRSN, the Institut de Recherche sur la Catalyse and the Ecole Nationale Superieure des Mines de Saint-Etienne. A PhD, co-directed by M. Pijolat from ENSMSE and myself, concerning this study will start in October 2003. Water radiolysis effects on iron corrosion are also studied in the particular case of vitrified nuclear waste containers, which will be stored in deep geological repositories. One ANDRA financed PhD, co-directed by Nathalie Moncoffre and myself, is

  20. Méthodes générales de synthèse des catalyseurs à base d'oxydes General Synthesis Methods for Mixed Oxide Catalysts

    Directory of Open Access Journals (Sweden)

    Courty Ph.

    2006-11-01

    Full Text Available De nombreux procédés industriels (industrie céramique, électronique, nucléaire catalyse hétérogène utilisent des matériaux constitués d'oxydes mixtes. Les études fondamentales réalisées en catalyse et leurs applications industrielles montrent qu'au-delà des diverses interprétations fines de l'activité catalytique des oxydes mixtes, une notion plus générale se dégage, celle de l'homogénéité de la phase active, donc du premier intermédiaire de fabrication du catalyseur (le précurseur. Les différentes méthodes de synthèse des oxydes mixtes, puis des catalyseurs, sont alors exposées. Pour chacune d'entre elles, il est montré comment l'obtention d'un précurseur homogène peut être favorisée et maintenue. Un exemple illustre le cas de l'oxyde mixte déposé sur support. Finalement, l'étape de mise en forme de l'oxyde mixte est évoquée, l'aspect économique de la fabrication du catalyseur conclut ce texte. A great mony industrial processes (ceramics, electronics, nuclear energy, hererogeneous catalysis use materials made up of mixed oxides. Fundamental research on catalysis and its industrial applications has shown that, over and beyond the various subtle interpretations of the catalytic activity of mixed oxides, a more general concept emerges, i. e. that of the homogeneity of the active phase, hence of the first catalyst-manufacturing intermediate (the precursor. Different synthesis methods for mixed oxides, and then for cotalysts, are described. The demonstration is made for each of them how the production of a homogeneous precursor con be enhanced and maintained. An example illustrotes the case of a mixed oxide deposited on a carrier. To conclude, the shaping of the mixed oxide is described, followed by the economic aspect of catalyst manufacturing.

  1. 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)

  2. Comparison of different methods of assessing the tar content of gases from wood gasification; Vergleich verschiedener Methoden zur Bestimmung des Teergehalts in Gasen aus der Holzvergasung

    Energy Technology Data Exchange (ETDEWEB)

    Moersch, O; Spliethoff, H; Hein, K R.G. [Stuttgart Univ. (Germany). Inst. fuer Verfahrenstechnik und Dampfkesselwesen

    1998-09-01

    The authors present a method developed at the Institute of Chemical Engineering and Steam Boiler Technology (IVD) of Stuttgart University for quasi-continuous online measurement of tar concentrations in gases from biomass gasification. The method is compared with other methods in terms of time requirements, accuracy, and cost: Gravimetry, wet chemical analysis, solid phase amino-adsorption (SPA), and online process gas chromatography. The measurements were carried out on the fluidized-bed combustion system of the IVD. Wood was gasified at 800 degrees centigrade with a fuel/air ratio of 0.25. The measured tar concentrations differed widely, i.e. between 0.8 and 6.8 g per cubic metre. (orig.) [Deutsch] In dieser Arbeit wird ein am Institut fuer Verfahrenstechnik und Dampfkesselwesen (IVD) entwickeltes Verfahren zur quasikontinuierlichen Online-Messung des Teergehalts im Gas aus der Biomassevergasung vorgestellt und mit anderen Methoden aus der Literatur im Hinblick auf Zeitaufwand, Genauigkeit und Kosten verglichen. Untersucht wurden dabei eine gravimetrische Methode, die nasschemische Bestimmung, das Solid-Phase-Amino Adsorptionsverfahren (SPA), sowie die Online Analyse mittels Prozess-Gaschromatograph. Die Messungen wurden an der Wirbelschichtvergasungsanlage des IVD durchgefuehrt. Vergast wurde Holz bei 800 C und einer Luftzahl von 0.25. Der mit den verschiedenen Verfahren ermittelte Teergehalt unterscheidet sich zum Teil erheblich. Es ergaben sich Werte zwischen 0.8 und 6.8 g/m{sup 3}. (orig.)

  3. Etude de la mesure des emittances transverses d'un faisceau par la methode des gradients. Application au cas d'une focalisation par solenoide

    CERN Document Server

    M'Garrech, S

    2002-01-01

    Within the framework of the ALTO project (Linear Accelerator near the Orsay Tandem), IPNO will recover the LAL station NEPAL, which will be used as the ALTO injecting system. To calculate the beam optics through the linear accelerator, it is necessary to determine the electron beam emittance at the exit of the buncher station. There are several methods to determine this emittance: direct methods, like the Pepper Pot technique, and indirect ones, like the three distances method and the three gradients one. The latter requires a variable optic element (quadrupole, solenoid...). In the case of the use of a solenoid, the horizontal and vertical motions are coupled, which implies an additional difficulty for the analysis of the measurements. The main goal of this report is to identify and to solve these mathematical difficulties, so as to determine at last the initial emittance. The treated example comes from a paper by R.Chehab et al [12], the code used is BETA, and resolution is done using the last square method...

  4. The origin of cholesterol in chyle demonstrated by nuclear indicator methods; Origines du cholesterol du chyle mises en evidence par la methode des indicateurs nucleaires

    Energy Technology Data Exchange (ETDEWEB)

    Vyas, M

    1962-07-01

    In order to obtain information about the mechanism of the intestinal absorption of cholesterol, rats having a lymphatic abdominal fistula are used. The animals receive either 4-{sup 14}C- cholesterol subcutaneously or orally, or the 1-{sup 14}C acetate. The study of the specific radio-activities of the cholesterol in chyle, in serum, in the lining, and in the intestinal contents makes it possible to define the roles played by the transfer cholesterol from the serum, by the cholesterol synthesised intestinally, and by the absorption cholesterol, in the formations of the lymph and of the chylomicrons. A new theory is proposed for the mechanism of cholesterol absorption. (author) [French] Pour obtenir des renseignements concernant le mecanisme de l'absorption intestinale du cholesterol, on utilise des rats porteurs d'une fistule lymphatique abdominale. Les animaux recoivent soit du cholesterol 4-{sup 14}C par voie sous-cutanee ou par voie orale, soit de l'acetate 1-{sup 14}C. L'etude des radioactivites specifiques du cholesterol du chyle, du serum, de la paroi et du contenu intestinal permet de preciser les roles joues par le cholesterol de transfert d'origine serique, par le cholesterol de synthese intestinale et par le cholesterol d'absorption, dans la formation de la lymphe et des chylomicrons. Une theorie nouvelle concernant le mecanisme de l'absorption du cholesterol est proposee. (auteur)

  5. Participation in sizing methods and management improvement for the isolated hybrid systems coupling photovoltaic generator and power generating unit. Application in developing countries; Participation a l'amelioration des methodes de dimensionnement et de gestion pour les systemes isoles hybrides de production d'electricite, couplant generateur photovoltaique et groupe electrogene. Application dans les pays en voie de developpement

    Energy Technology Data Exchange (ETDEWEB)

    Camez, C.

    2004-09-15

    One of the applications justifying more the use of renewable energies is the electrification of isolated sites. Sites for which connection to the local distribution network is being out of price or impossible. These sites are most of the time electrified with a diesel generator. This technology is tested and mature however two major disadvantages can be raised here: necessary routine maintenance and the fuel provisioning management. Photovoltaic system can answer here the request and little solar home systems (100 Watts) are installed. In the particular situation of a village electrification, the consumers quickly see in these systems a strong limitation with the development. Reliability, evolution, comfort, service are the masters words here, the development of a micro industry also seems necessary to a village development. It is then necessary to propose a micro network type solution. Such a generator cannot be think completely photovoltaic, presenting an important over-cost compared to a conventional solution. The idea of conventional and renewable energy coupling is born. Such a multi-source system: hybrid, implies an increased sizing and management complexity. An analysis software tool was developed: HYPSIM, this one makes it possible to optimize the operation of such a system. HYPSIM made possible to - Justify the relevance of a photovoltaic/diesel generator/batteries system. - Conclude on the sizing criteria to be observed. (author)

  6. High temporal resolution magnetic resonance imaging: development of a parallel three dimensional acquisition method for functional neuroimaging; Imagerie par resonance magnetique a haute resolution temporelle: developpement d'une methode d'acquisition parallele tridimensionnelle pour l'imagerie fonctionnelle cerebrale

    Energy Technology Data Exchange (ETDEWEB)

    Rabrait, C

    2007-11-15

    Echo Planar Imaging is widely used to perform data acquisition in functional neuroimaging. This sequence allows the acquisition of a set of about 30 slices, covering the whole brain, at a spatial resolution ranging from 2 to 4 mm, and a temporal resolution ranging from 1 to 2 s. It is thus well adapted to the mapping of activated brain areas but does not allow precise study of the brain dynamics. Moreover, temporal interpolation is needed in order to correct for inter-slices delays and 2-dimensional acquisition is subject to vascular in flow artifacts. To improve the estimation of the hemodynamic response functions associated with activation, this thesis aimed at developing a 3-dimensional high temporal resolution acquisition method. To do so, Echo Volume Imaging was combined with reduced field-of-view acquisition and parallel imaging. Indeed, E.V.I. allows the acquisition of a whole volume in Fourier space following a single excitation, but it requires very long echo trains. Parallel imaging and field-of-view reduction are used to reduce the echo train durations by a factor of 4, which allows the acquisition of a 3-dimensional brain volume with limited susceptibility-induced distortions and signal losses, in 200 ms. All imaging parameters have been optimized in order to reduce echo train durations and to maximize S.N.R., so that cerebral activation can be detected with a high level of confidence. Robust detection of brain activation was demonstrated with both visual and auditory paradigms. High temporal resolution hemodynamic response functions could be estimated through selective averaging of the response to the different trials of the stimulation. To further improve S.N.R., the matrix inversions required in parallel reconstruction were regularized, and the impact of the level of regularization on activation detection was investigated. Eventually, potential applications of parallel E.V.I. such as the study of non-stationary effects in the B.O.L.D. response

  7. The Pulsed Neutron Technique Applied to Fast Non-Multiplying Assemblies; Application de la Methode des Neutrons Pulses aux Assemblages Non Multiplicateurs a Neutrons Rapides; Primenenie metoda impul'snykh nejtronov pri izuchenii povedeniya bystrykh nejtronov v nerazmnozhayushchikh sborkakh; Aplicacion de la Tecnica de los Neutrones Pulsados a Conjuntos Rapidos de Materiales No Multiplicadores

    Energy Technology Data Exchange (ETDEWEB)

    Beghian, L. E.; Wilensky, S. [Massachusetts Institute of Technology, Cambridge, MA (United States)

    1965-10-15

    Graaff a impulsions de l'ordre de la nanoseconde pour etudier le comportement de neutrons rapides dans des assemblages metalliques non multiplicateurs. Ils ont mesure les sections efficaces non elastiques du fer pour les neutrons rapides. La methode employee est semblable a celle qu'on utilise pour mesurer les sections efficaces d'absorption dans des assemblages a neutrons thermiques, avec cette difference que les temps de decroissance pour les neutrons rapides sont de l'ordre de la nanoseconde et non de la microseconde. Des bouffees de neutrons monoenergetiques d'une nanoseconde sont introduites dans des assemblages en fer de dimensions diverses. On remarque que dans ces assemblages le flux de neutrons decroit exponentiellement avec une constante de decroissance caracteristique. La constante de decroissance est composee d'une somme de termes qui representent la perte de neutrons due aux fuites et a la degradation en energie. La degradation en energie represente une perte de neutrons, car un detecteur de neutrons dont les donnees sont entachees d'une erreur systematique est utilise. On peut determiner le terme correspondant a la diffusion elastique et inelastique en mesurant la constante de decroissance consideree comme une fonction des dimensions de l'assemblage. Suit un developpement theorique pour le calcul de la fraction de ce terme qui est due a la diffusion elastique et, par consequent, pour la determination de la section efficace non elastique. Le procede theorique de calcul de cette fraction a fait l'objet de verifications experimentales. Les auteurs ont mesure la section efficace non elastique du fer par cette methode pour des energies de neutrons primaires comprises entre 0,8 et 1,5 MeV. La methode de la source puisee decrite ci-dessus a ete utilisee pour mesurer des constantes de decroissance pour des plaques de plomb. Les conditions de l'experience sont approximativement conformes aux hypotheses generalement admises lorsqu'on resout l'equation de transport de

  8. On the structure of heavy metals; Sur la structure des metaux lourds

    Energy Technology Data Exchange (ETDEWEB)

    Friedel, J [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires; Faculte des Sciences de l' Universite de Paris, 75 (France)

    1958-07-01

    The properties of the last series of Mendeleef's table are compared with those of the elements of the preceding series. This comparison suggests an electronic structure of the 'transition metal' type, with narrow bands, at the beginning of this series (up to certain phases at least of plutonium); then of the rare earth metal type, with independent non-saturated internal layers, further on in the series. The 5 f orbits seem to play an important part in these two types of structure, from uranium on. A more detailed study of the very heavy elements (americium and beyond) and alloys would allow these conclusions to be confirmed. Certain general points, concerning the nature of homopolar connections and paramagnetism in the transition metals, are developed in an additional section. (author) [French] Les proprietes des elements de la derniere serie du tableau de Mendeleef sont comparees a celles des elements des series precedentes. Cette comparaison suggere une structure electronique du type 'metal de transition', a bandes etroites, au debut de cette serie (jusqu'a certaines phases au moins du plutonium); puis du type d'un metal des terres rares, a couches internes non saturees independantes, au-dela dans la serie. Les orbitales 5 f semblent jouer un r e important, dans ces deux types de structures, a partir de l'uranium. Une etude plus poussee des elements tres lourds (americium et au-dela) et des alliages permettrait de confirmer ces conclusions. Certains points generaux, concernant la nature des liaisons homopolaires et le paramagnetisme dans les metaux de transition, sont developpes en annexe. (auteur)

  9. AU-DELA DES METHODES TRADITIONNELLES DANS LACQUISITION DES COMPETENCES LINGUISTIQUES DANS UNE LANGUE ETRANGERE – LE BLOG, UN OUTIL PRATIQUE?

    Directory of Open Access Journals (Sweden)

    BOGDAN Rodica

    2014-12-01

    Full Text Available Although the classical and traditional methods have proven effective in seizing on foreign language skills by pupils and students, new means of communication and dissemination of information - in the virtual world via Internet - are continuous and opportune challenges towards progress. The purpose of this paper is to question the effectiveness of new instruments - namely the blog - for conveying and assimilating the skills necessary for communicating in another language. We live in a world in which a wide range of public figures stemming from diverse environments, such as the academia, mass-media, political and cultural environment, etc. use this tool - the blog - in order to present in a personal manner their knowledge or opinions, to promote a different kind of dialogue with their readers, with the audience, with their constituency or with those interested in the proposed topics. The journalist and the blogger are often tantamount. Great online publications have a blog button on their site. In such conditions, is the blog a practical tool for both the teacher and the economy student learning a new language? A series of pertinent questions are posed: to which extent can the blog be used as an instrument in teaching and learning a foreign language? Is the virtual platform a proper place for designing, displaying and posting both practical and theoretical topics? If preparing such a topic - at an economy student's hands - entails a significant effort as a self-taught, is this effort best assessed when presenting a paper before a professor, in the interaction between the two, which coincides with the evaluation and assessment of the student's work? While the information content is taught the same for all students, regarding one on one assimilation and evaluation, could an individual blog - moderated by the student - or a collective blog in which all students have access be more appropriate? Is the use of a virtual platform more effective than

  10. 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

  11. Principle of the determination of neutron multiplication coefficients by the Monte Carlo method. Application. Description of a code for ibm 360-75; Principe de la determination des coefficients de multiplication neutronique par methode de Monte-Carlo. Application. Description d'un code pour IBM 360-75

    Energy Technology Data Exchange (ETDEWEB)

    Moreau, J; Parisot, B [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1969-07-01

    The determination of neutron multiplication coefficients by the Monte Carlo method can be carried out in different ways; the are first examined particularly complex geometries; it makes use of multi-group isotropic cross sections. The performances of this code are illustrated by some examples. (author) [French] La determination des coefficients de multiplication neutronique par methode de Monte Carlo peut se faire par differentes voies, elles sont successivement examinees et comparees. On en deduit un code rapide pour des geometries particulierement complexes, il utilise des sections efficaces multigroupes isotropes. Les performances de ce code sont demontrees par quelques exemples. (auteur)

  12. 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

  13. Simulation of land use evolution by discrete events method: Application to “la chaîne des puys” from XV to XVIII Century

    Directory of Open Access Journals (Sweden)

    Y. Michelin

    1998-01-01

    Full Text Available By using a discrete event method, simulation of land use evolution has been applied to a landscape model of “la ChaÎne des Puys” (French Massif Central during along period (XV–XVIII centuries. The indications concerning the evolution of land use are in conformity with the observation of actual situations but the dynamic changes are faster than in actual facts. In spite of limitations due to necessary simplifications, it is now established that the discrete event method is efficient to simulate land use evolution during a long period. The model is immediately able to describe actual dynamics and to show sensitive variables with their critical values. Although oversimplified, it shows how far factors such as level of crops production and taxation can influence land use and landscape changes with a more or less lengthy period. In the future, the model should be bettered by introducing other determined and/or stochastic events.

  14. Development of a method for studying non-linear phenomena in plasma; Mise au point d'une methode d'etude des phenomenes non lineaires dans un plasma

    Energy Technology Data Exchange (ETDEWEB)

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

    1965-03-01

    The study of non-linear phenomena resulting from the interaction of powerful electro-magnetic waves with an electron gas is the basis of the p best methods for measuring the frequency of electronic collisions in the ionosphere. In laboratory plasma the appearance of these phenomena is connected with a powerful critical field. Although we have used a relatively low-power electromagnetic source, we have been able to develop a simple hyper-frequency method making it possible to study these phenomena to measure them and to put forward an elementary interpretation. An electromagnetic wave provided by a 1 watt klystron interacts with a HF discharge (25 MHz) in the volume of a TE{sub 111} cavity. The tube containing the discharge and the axis of the cylindrical cavity are co-linear with a magnetic field which can attain a value such that the wave frequency is equal to the gyromagnetic frequency of the electrons. The resonance curve for the cavity, which depends on the electronic density and the frequency of collisions, becomes increasingly dissymmetric as the absorbed power increases and as the gyromagnetic frequency of the electrons approaches that of the incident wave. By studying the resonance, it is possible to calculate the proportionality coefficients relating the density and collision frequency variations with the absorbed power. The experiments were carried out by causing the following to vary separately: the incident UHF power, the initial electronic density, the pressure of the neutral ambient gas, and the axial magnetic field. The variation in the electronic density as a function of the magnetic field for a high UHF power shows a resonance of dissymmetrical form, sometimes with a sharp peak in the neighbourhood of {omega}{sub H}. The possibility of applying these properties to the construction of practical devices, is under consideration. (author) [French] L'etude des phenomenes non lineaires dus a l'interaction d'ondes electro-magnetiques puissantes avec un

  15. A method for reducing memory errors in the isotopic analyses of uranium hexafluoride by mass spectrometry; Methode de reduction des erreurs de memoire dans les analyses isotopiques de l'hexafluorure d'uranium par spectrometrie de masse

    Energy Technology Data Exchange (ETDEWEB)

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

    1961-07-01

    One of the most serious causes of systematic error in isotopic analyses of uranium from UF{sub 6} is the tendency of this material to become fixed in various ways in the mass spectrometer. As a result the value indicated by the instrument is influenced by the isotopic composition of the substances previously analysed. The resulting error is called a memory error. Making use of an elementary mathematical theory, the various methods used to reduce memory errors are analysed and compared. A new method is then suggested, which reduces the memory errors to an extent where they become negligible over a wide range of {sup 235}U concentration. The method is given in full, together with examples of its application. (author) [French] Une des causes d'erreurs systematiques les plus graves dans les analyses isotopiques d'uranium a partir d'UF{sub 6} est l'aptitude de ce produit a se fixer de diverses manieres dans le spectrometre de masse. Il en resulte une influence de la composition isotopique des produits precedemment analyses sur la valeur indiquee par l'appareil. L'erreur resultante est appelee erreur de memoire. A partir d'une theorie mathematique elementaire, on analyse et on compare les differentes methodes utilisees pour reduire les erreurs de memoire. On suggere ensuite une nouvelle methode qui reduit les erreurs de memoire dans une proportion telle qu'elles deviennent negligeables dans un grand domaine de concentration en {sup 235}U. On donne le mode operatoire complet et des exemples d'application. (auteur)

  16. X-spectrographic method for plutonium detection. Application to contamination measurements in humans; Etude d'une methode de detection du plutonium par spectrographie X. Application a la mesure des contaminations sur l'homme

    Energy Technology Data Exchange (ETDEWEB)

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

    1967-07-01

    After reviewing the radio-toxicology of plutonium 239 and conventional detection methods using its {alpha}-radiation, the author considers the measurement of the X emission spectrum of plutonium 239 using a proportional counter filled with argon under pressure. This preliminary work leads to the third part of this research involving the detailed study of the possibilities of applying thin alkali halide crystal scintillators to the detection of soft plutonium X-rays; there follows a systematic study of all the parameters liable to render the detection as sensitive as possible: movement due to the photomultiplier itself and its accessory electronic equipment, nature and size of the crystal scintillator as well as its mode of preparation, shielding against external parasitic radiation. Examples of some applications to the measurement of contamination in humans give an idea of the sensitivity of this method. (author) [French] Apres un apercu de la radiotoxicologie du plutonium 239 et des methodes classiques de detection par son rayonnement {alpha}, on etudie le spectre d'emission X du plutonium 239 avec un compteur proportionnel rempli avec de l'argon sous pression. Ce travail preliminaire permet d'aborder la troisieme partie de cette etude dans laquelle nous examinons d'une fagon approfondie les possibilites d'application des cristaux scintillateurs minces d'halogenure alcalin a la detection du rayonnement X mou du plutonium; suit une etude systematique de tous les parametres susceptibles de rendre la detection aussi sensible que possible: mouvement propre du photomultiplicateur et de l'electronique associee, nature et dimensions du cristal scintillateur ainsi que son mode de fabrication, blindage contre les rayonnements parasites exterieurs. Quelques applications a la mesure des contaminations sur l'homme permettent d'apprecier la sensibilite de cette methode. (auteur)

  17. ANALYSE DES PERCEPTIONS LOCALES ET DES FACTEURS ...

    African Journals Online (AJOL)

    AISA

    1Faculté des Sciences Agronomiques (FSA), Université d'Abomey-Calavi (UAC), 01 BP 526 Cotonou Bénin. Email : cgbemavo@yahoo.fr. 2Institut National des Recherches Agricoles du Bénin, Centre de Recherches Agricoles d'Agonkanmey (CRA-A),. Laboratoire des Sciences du Sol, Eau et Environnement (LSSEE).

  18. Mesures de contraintes in-situ. Méthode de relaxation des carottes Measuring in-Situ Stresses. Relaxation Method with Core Samples

    Directory of Open Access Journals (Sweden)

    Perreau P.

    2006-11-01

    Full Text Available Dans cet article, on se propose de présenter les premiers résultats de l'étude de la méthode d'évaluation des contraintes par mesure de déformations différées d'une carotte après son extraction. Le travail correspondant a été réalisé dans le cadre du projet ARTEP Fracturation hydraulique . Les principes de cette méthode et les quelques éléments d'interprétation récemment publiés dans la littérature sont exposés dans un premier temps. Les résultats de deux campagnes de mesures sur deux puits de la SNEA-P (Soudron, novembre 1985 et Lanot, juillet 1986 sont ensuite présentés. Ces essais ont mis en évidence que les déformations différées d'une carotte dues au relachement des contraintes sont effectivement mesurables. Cependant, une interprétation quantitative de ces mesures nécessite une amélioration des conditions expérimentales (stabilisation thermique, stabilisation de l'état de saturation. This article describes the first results of research on a method of evaluating stresses by measuring the differred deformations of a core sample after it has been extracted. The corresponding research was done within the framework of an ARTEP project on Hydraulic Fracturing . The principles of this method and several interpretation aspects published recently in the literature are described in the first part. Then the results of two measurement campaigns using two SNEA-P wells (Soudron in November 1985 and Lanot in July 1986 are described. These tests revealed that the differed deformations of a core sample due to the relaxing of stresses can effectively be measured. However, a quantitative interpretation of these measurements requires an improvement to be made in the experimental conditions (thermal stabilization, stabilization of the state of saturation.

  19. An Appraisal of Analytical Methods for Plutonium and their Applications to the Analysis of Nuclear Materials; Evaluation des Methodes Analytiques de Dosage du Plutonium et de Leur Application a l'Analyse des Matieres Nucleaires; Otsenka analiticheskikh metodov opredeleniya plutoniya i ikh primenenie dlya analiza yadernykh materialov; Metodos Analiticos de Determinacion del Plutonio y su Empleo en el Analisis de Materiales Nucleares

    Energy Technology Data Exchange (ETDEWEB)

    Milner, G. W.C.; Phillips, G. [Atomic Energy Research Establishment, Harwell, Berks. (United Kingdom)

    1966-02-15

    programmes for new nuclear fuels. (author) [French] Il existe plusieurs methodes de dosage de la teneur en plutonium des matieres nucleaires. Pour les quantites de l'ordre du milligramme, les methodes utilisables sont la spectro- photometiie differentielle fondee sur la couleur de Pu (III), la gravimetrie fondee sur PuO{sub 2}, le comptage gamma et les methodes de reduction/oxydation comprenant les titrages poientiometriques et amperemetriques et la coulombmetrie a potentiel constant. Pour les quantites de Tordre du microgramme, le comptage alpha, la dilution isotopique et les methodes polarigraphiques sont a utiliser. Certaines methodes conviennent mieux que d'autres a des types determines d'echantillons et l'analyste soucieux d'obtenir les meilleurs resultats se heurte a un choix difficile. Les auteurs exposent les avantages et les inconvenients des methodes citees tels qu'ils se sont degages de l'experience acquise au cours des annees a l'Atomic Energy Research Establishment, et ils discutent l'exactitude, la precision, la sensibilite de ces methodes, et d'autres caracteristiques presentant un interet particulier. Certaines methodes ne peuvent etre utilisees si l'on n'a, dans une certaine mesure, separe le plutonium des autres constituants de l'echantillon et le memoire commente l'experience acquise avec l'echange d'anions et les procedes de chromatographie a phase inversee utilises a cette fin, en insistant surtout sur la mesure dans laquelle cette methode convient aux echantillons radioactifs. Les auteurs etudient en outre les nombreux problemes qui se sont poses lors de l'application (d'ailleurs couronnee de succes) de ces methodes a l'analyse des alliages de plutonium, des ceramiques et des cermets dans differentes combinaisons contenant de l'uranium, du thorium, du fer, du chrome, du molybdene, du cerium et du cobalt. Us exposent les difficultes de la dissolution des echantillons et de la reduction du plutonium a l'etat de valence voulu, ainsi que les avantages

  20. New instruments and methods for measuring the concentration of radioactive products in the atmosphere; Appareils recents et methodes nouvelles pour la mesure de la concentration des produits radioactifs dans l'atmosphere

    Energy Technology Data Exchange (ETDEWEB)

    Jehanno, C; Blanc, A; Lallemant, C; Roux, G [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1959-07-01

    ) [French] Differents enregistreurs pour aerosols radioactifs ont ete realises pour mesurer la pollution de l'atmosphere des laboratoires ou l'atmosphere exterieure. EAR 600. - Permet de mesurer en continu instantanement et 3 a 10 heures apres le prelevement des concentrations d'aerosols emetteurs {alpha} ou {beta} allant de quelques 10{sup -11} a quelques 10{sup -8} curies par metre cube d'air. EAR 800. - Permet de mesurer en continu des concentrations d'aerosols emetteurs {alpha} allant de 10{sup -11} a 10{sup -5} curie par metre cube d'air, et des concentrations d'aerosols emetteurs {beta} allant de 10{sup -11} a 10{sup -1} curie par metre cube d'air. EAR PLUTONIUM. - Permet de detecter en quelques minutes 1000 DMP (2.10{sup -9} curie par metre cube) et en 8 heures 1 DMP (2.10{sup -12} curie par metre cube). Deux methodes sont utilisees pour separer l'activite due au plutonium de celle due aux derives du radon et du thoron: a) par discrimination d'amplitude, b) par les coincidences (a,b) RaC' et ThC-ThC'. SP 4. - Monte sur jeep, cet ensemble permet la mesure de l'irradiation produite au sol par le panache des piles. La sensibilite est de 5{mu}R/h. A.D.I.R. - Cet appareil autonome et portatif est destine a la mesure instantanee des teneurs en radon de l'atmosphere des mines. Il permet de mesurer des teneurs de l'air variant entre 0,4 et 400.10{sup -10} curie par litre d'air (0,4 et 400 DPM). La mesure des retombees radioactives est faite apres collection de cette activite par un pluviometre special comportant une surface adhesive et une cartouche de resines echangeuses d'ions. La radioactivite des retombees varie entre quelques 10{sup -9} et quelques 10{sup -7} curie par metre carre et par mois. La mesure des concentrations de l'atmosphere en produits de fission est faite apres collection sur papier filtre. Les concentrations mesurees dans l'air au niveau du sol varient entre 10{sup -13} et 10{sup -12} curie par metre cube. (auteur)

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

    Directory of Open Access Journals (Sweden)

    Selly CAMARA

    2017-05-01

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

  2. Origine et developpement des industries de la langue (Origin and Development of Language Utilities). Publication K-8.

    Science.gov (United States)

    L'Homme, Marie-Claude

    The evolution of "language utilities," a concept confined largely to the francophone world and relating to the uses of language in computer science and the use of computer science for languages, is chronicled. The language utilities are of three types: (1) tools for language development, primarily dictionary databases and related tools;…

  3. The sustainable development of transports: the motors and the fuels; Le developpement durable des transports: quels moteurs, quels carburants?

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2005-07-01

    This panorama 2005 between politicians, industrialists and scientists discussed the following topics: exploration-production activities and markets, refining and petrochemistry, the future world gas market, the petroleum supply and demand, the new petroleum and gas reserves, the today and tomorrow alternative fuels, the biofuels in the world, the hybrid vehicles future, the energy consumption in the transport sector, the road fuels in europe and the increase of diesel fuel, the de-pollution techniques of industrial vehicles. The slides of the interventions are provided. The sheets ''le point sur'' of the year 2005 are also provided. (A.L.B.)

  4. Energy and durable development: the place of the renewable energies; Energie et developpement durable: la place des energies renouvelables

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-07-01

    The 29 may 2000, took place at the UNESCO, a colloquium on the place of the renewable energies facing the economic development. This document presents the opening presentation of A. Antolini and L. Jospin and the colloquium papers and debates in the following four domains: the energy challenges of the durable development, the renewable energies sources facing the european directive, the thermal renewable energies (solar, geothermics and biomass) and the greenhouse effect, the world market of the renewable energies. (A.L.B.)

  5. Recommendations for a sustainable development of biofuels in France; Recommandations pour un developpement durable des biocarburants en France

    Energy Technology Data Exchange (ETDEWEB)

    Douaud, A.; Gruson, J.F

    2006-01-15

    The biofuels are presented as a solution to the greenhouse gases and the petroleum consumption decrease. The development of the biofuels needs an active research of the production, transformation and use costs improvement. It will be necessary to prepare the market of the biofuels to the globalization. Some recommendations are also provided in the domains of the vegetal oil ester, the ethanol for the diesel and for the development of simulation tools to evaluate the costs. (A.L.B.)

  6. The renewable energies: major tools for our development; Les energies renouvelables: des outils essentiels pour notre developpement

    Energy Technology Data Exchange (ETDEWEB)

    Antolini, A.

    2004-06-15

    Even if the fossil fuels use is always possible for the few ten years, the renewable energies will answer the new challenges of the society. In this framework the author takes stock on the greenhouse effect, the energy demand, the nuclear energy and on different renewable energies sources: the solar energy, the wind power, the biomass, the hydroelectricity, the cogeneration and the biofuels. (A.L.B.)

  7. Contribution to the methods for estimating uranium deposits (1963); Contribution aux methodes d'estimation des gisements d'uranium (1963)

    Energy Technology Data Exchange (ETDEWEB)

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

    1964-02-15

    be taken in some cases. A detailed alphabetical index is intended to help find in this publication the definitions, formulae or theories that most interest the reader. (author) [French] Apres avoir rappele ce qu'est un gisement, de valeur economique, sur la base du marginalisme, l'auteur distingue plusieurs categories de reserves suivant le degre de connaissance du gite et suivant le poste d'exploitation ou est considere le minerai. Il rejette les anciennes categories 'a vue', 'probable' et 'possible' pour les remplacer par des categories mieux adaptees. Les reserves sensu stricto sont celles pour lesquelles on est en mesure de calculer l'erreur aleatoire d'estimation. Une notion est introduite a ce sujet, c'est le contraste naturel des teneurs dans un gite (coefficient de dispersion absolu {alpha}). L'auteur distingue 3 formes de reconnaissance des gites, la mauvaise, la bonne et l'ideale. La premiere est la reconnaissance anarchique trop souvent recontree la seconde est la reconnaissance logique fondee sur une implantation systematique des galeries, sondages, etc. La troisieme, difficile a atteindre, est celle qui minimise la depense des recherches pour une precision fixee a l'avance. Une partie de l'ouvrage traite des erreurs d'echantillonnage telles que celles resultant du quartage d'un lot (theorie de Pierre GY), ou celles issues de l'emploi de la radioactivite pour estimer les teneurs. Une autre partie traite des erreurs d'extension (assimilation du gite a ses echantillons) et donne les formules essentielles pour calculer ces erreurs aleatoires (geostatistique de Matheron). A propos de l'estimateur lui-meme, on note la disharmonie entre l'echantillon et sa zone d'influence, et le moyen de remedier a cette discordance par le 'krigeage' est fourni dans l'ouvrage. La these donne de nombreux exemples des differents parametres numeriques

  8. Contribution to the methods for estimating uranium deposits (1963); Contribution aux methodes d'estimation des gisements d'uranium (1963)

    Energy Technology Data Exchange (ETDEWEB)

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

    1964-02-15

    index is intended to help find in this publication the definitions, formulae or theories that most interest the reader. (author) [French] Apres avoir rappele ce qu'est un gisement, de valeur economique, sur la base du marginalisme, l'auteur distingue plusieurs categories de reserves suivant le degre de connaissance du gite et suivant le poste d'exploitation ou est considere le minerai. Il rejette les anciennes categories 'a vue', 'probable' et 'possible' pour les remplacer par des categories mieux adaptees. Les reserves sensu stricto sont celles pour lesquelles on est en mesure de calculer l'erreur aleatoire d'estimation. Une notion est introduite a ce sujet, c'est le contraste naturel des teneurs dans un gite (coefficient de dispersion absolu {alpha}). L'auteur distingue 3 formes de reconnaissance des gites, la mauvaise, la bonne et l'ideale. La premiere est la reconnaissance anarchique trop souvent recontree la seconde est la reconnaissance logique fondee sur une implantation systematique des galeries, sondages, etc. La troisieme, difficile a atteindre, est celle qui minimise la depense des recherches pour une precision fixee a l'avance. Une partie de l'ouvrage traite des erreurs d'echantillonnage telles que celles resultant du quartage d'un lot (theorie de Pierre GY), ou celles issues de l'emploi de la radioactivite pour estimer les teneurs. Une autre partie traite des erreurs d'extension (assimilation du gite a ses echantillons) et donne les formules essentielles pour calculer ces erreurs aleatoires (geostatistique de Matheron). A propos de l'estimateur lui-meme, on note la disharmonie entre l'echantillon et sa zone d'influence, et le moyen de remedier a cette discordance par le 'krigeage' est fourni dans l'ouvrage. La these donne de nombreux exemples des differents parametres numeriques qui caracterisent un gite d'uranium (coefficient de dispersion absolu) ou un minerai d'uranium (parametre de liberation), ainsi que plusieurs exemples de droite de correspondance de

  9. New Methods and Facilities for the Measurement of Physical Properties of Reactor Components and Irradiated Materials; Nouveaux Procedes et Instruments de Mesure des Proprietes Physiques des Elements de Reacteur et des Matieres Irradiees; Novye metody i sredstva izmereniya fizicheskikh s vojstv komponentov reaktora i obluchennykh materialov; Nuevos Metodos y Equipos para Medir Propiedades Fisicas de Componentes de Reactor y de Materiales Irradiados

    Energy Technology Data Exchange (ETDEWEB)

    Foerster, F.; Mueller, P. [Institut Dr. Foerster, Reutlingen, Federal Republic of Germany (Germany)

    1965-09-15

    direct reading of the permeability and stainless- steel components. The correlation between permeability and {Delta} ferrite content is explained. Measurements of the {Delta} ferrite percentage across welds in stainless-steel tubes and measurements of the {Delta} ferrite precipitations as a function of the plastic strain are discussed (hammer-forging of reactor fuel-elements). (author) [French] Les auteurs decrivent un instrument permettant de mesurer et d'enregistrer automatiquement le module de Young, le module de cisaillement et la capacite d'amortissement en fonction de la temperature et du temps. On mesure le module de Young en excitant des specimens de diverses dimensions a leur frequence propre. On mesure la capacite d'amortissement d'apres la libre decroissance de la vibration ou la largeur a mi-hauteur de la courbe de resonance. Le memoire donne des exemples de mesures de la guerison apres irradiation et apres deformation inelastique, ainsi que des exemples du degre de graphitisation. Les auteurs demontrent que l'on peut detecter des defauts et des variations de densite dans les banes de graphite. Ils expliquent, en outre, une methode d'etude de la fixation de pastilles d' UO{sub 2} sur des tubes en acier austenitique a parois minces. Us decrivent un four special pour l'etude du comportement elastique ou inelastique de specimens 'chauds ' a des temperatures variant entre 20 et 1000 Degree-Sign C. Les auteurs discutent le controle de la qualite de metaux non ferreux par mesure de ia conductivite electrique au moyen de courants de Foucault et decrivent un instrument permettant de mesurer sans aucun contact la conductivite electrique de metaux non ferreux. Ils expliquent la correlation entre la conductivite electrique et l'allongement sous l'effet des contraintes dans le cas de metaux et d'alliages non ferreux. Ils s'attachent particulierement a la mesure d'echantillons de petites dimensions. Ils decrivent un dispositif pour la mesure directe a distance dans la

  10. Qualification of the calculational methods of the fluence in the pressurised water reactors. Improvement of the cross sections treatment by the probability table method; Qualification des methodes de calculs de fluence dans les reacteurs a eau pressurisee. Amelioration du traitement des sections efficaces par la methode des tables de probabilite

    Energy Technology Data Exchange (ETDEWEB)

    Zheng, S H

    1994-01-01

    It is indispensable to know the fluence on the nuclear reactor pressure vessel. The cross sections and their treatment have an important rule to this problem. In this study, two ``benchmarks`` have been interpreted by the Monte Carlo transport program TRIPOLI to qualify the calculational method and the cross sections used in the calculations. For the treatment of the cross sections, the multigroup method is usually used but it exists some problems such as the difficulty to choose the weighting function and the necessity of a great number of energy to represent well the cross section`s fluctuation. In this thesis, we propose a new method called ``Probability Table Method`` to treat the neutron cross sections. For the qualification, a program of the simulation of neutron transport by the Monte Carlo method in one dimension has been written; the comparison of multigroup`s results and probability table`s results shows the advantages of this new method. The probability table has also been introduced in the TRIPOLI program; the calculational results of the iron deep penetration benchmark has been improved by comparing with the experimental results. So it is interest to use this new method in the shielding and neutronic calculation. (author). 42 refs., 109 figs., 36 tabs.

  11. A Gibbs potential expansion with a quantic system made up of a large number of particles; Un developpement du potentiel de Gibbs d'un systeme compose d'un grand nombre de particules

    Energy Technology Data Exchange (ETDEWEB)

    Bloch, Claude; Dominicis, Cyrano de [Commissariat a l' energie atomique et aux energies alternatives - CEA, Centre d' Etudes Nucleaires de Saclay, Gif-sur-Yvette (France)

    1959-07-01

    Starting from an expansion derived in a previous work, we study the contribution to the Gibbs potential of the two-body dynamical correlations, taking into account the statistical correlations. Such a contribution is of interest for low density systems at low temperature. In the zero density limit, it reduces to the Beth Uhlenbeck expression of the second virial coefficient. For a system of fermions in the zero temperature limit, it yields the contribution of the Brueckner reaction matrix to the ground state energy, plus, under certain conditions, additional terms of the form exp. (β |Δ|), where the Δ are the binding energies of 'bound states' of the type first discussed by L. Cooper. Finally, we study the wave function of two particles immersed in a medium (defined by its temperature and chemical potential). lt satisfies an equation generalizing the Bethe Goldstone equation for an arbitrary temperature. Reprint of a paper published in 'Nuclear Physics' 10, 1959, p. 181-196 [French] Partant d'un developpement extrait d'un precedent travail, nous etudions la contribution au potentiel de Gibbs des relations dynamiques du systeme de deux corps, en tenant compte des relations statistiques. Une telle contribution presente de l'interet pour les systemes a densite faible et a basse temperature. A la densite limite zero, elle se ramene a l'expression de Beth Uhlenbeck du second coefficient virial. Pour un systeme de fermions a la temperature limite zero, il produit la contribution de la matrice de reaction de Brueckner au niveau fondamental, plus, dans certaines conditions, des termes additionnels de la forme exp. (β |Δ|), ou les Δ sont les energies de liaison des 'etats lies' du premier type, discutes auparavant par L. Cooper. Finalement, on etudie la fonction d'onde de deux particules immerges dans un milieu (definie par sa temperature et son potentiel chimique). Il satisfait a une equation generalisant l'equation de Bethe Goldstone pour une temperature arbitraire

  12. Global Methodology to Integrate Innovative Models for Electric Motors in Complete Vehicle Simulators Méthodologie générale d’intégration de modèles innovants de moteurs électriques dans des simulateurs véhicules complets

    Directory of Open Access Journals (Sweden)

    Abdelli A.

    2011-11-01

    . Comment reduire les emissions moyennes de CO2 des vehicules particuliers a 120 g/km en 2012 et 95 g/km en 2020 comme le prevoit l’accord conclu entre la Commission Europeenne et les constructeurs europeens ? Cette question a reponses multiples preoccupe a l’heure actuelle l’ensemble du monde automobile. L’electrification des vehicules semble etre une des solutions les plus pertinentes, ce qui pousse les constructeurs a envisager des vehicules hybrides de plus en plus innovants. Cette solution, theoriquement tres interessante, complexifie encore un peu plus les groupes moto-propulseurs des vehicules, ce qui necessite l’utilisation d’outils de simulation adequats pour reduire les couts et les durees de developpement. La simulation systeme, outil deja primordial dans le processus de developpement des moteurs a combustion interne, devient alors incontournable. Pour etudier ce type d’architectures hybrides complexes, et a l’instar des modeles physiques developpes pour le moteur a combustion interne, la simulation systeme doit se doter de modeles predictifs comparables pour les machines electriques. Des leurs specifications, ces modeles doivent integrer certaines contraintes tres exigeantes sur les temps de simulation, contrainte garantissant par la suite une plus large utilisation des simulateurs, notamment pour le developpement et la validation de strategies de controle. L’objectif de ce papier est donc de presenter une methodologie generale de developpement de modeles de machines electriques, modeles ayant pour objectif final d’etre integres dans un simulateur vehicule complet. Cette methodologie met en scene differents types de modelisations (modeles elements finis, modeles de caracterisation, modele de simulation permettant un compromis temps de calcul – precision adequat. Cette methodologie a ete deployee avec succes pour la modelisation d’un moteur synchrone a aimants permanents. A l’issue du processus de modelisation, ce dernier a ete integre

  13. Improved Mask Protected DES using RSA Algorithm

    Directory of Open Access Journals (Sweden)

    Asha Latha S.

    2016-01-01

    Full Text Available The data encryption standard is a pioneering and farsighted standard which helped to set a new paradigm for encryption standards. But now DES is considered to be insecure for some application. Asymmetric mask protected DES is an advanced encryption method for effectively protecting the advanced DES. There are still probabilities to improve its security. This paper propose a method, which introduce a RSA key generation scheme in mask protected DES instead of plain key, which result in enhancement in the security of present asymmetric mask protected DES. We further propose a Vedic mathematical method of RSA implementation which reduce the complexity of computation in RSA block thereby resulting in reduced delay (four timesthat improves the performance of overall system. The software implementation was performed using Xilinx 13.2 and Model-Sim was used for the simulation environment.

  14. Les reseaux de politique publique comme facteur d'influence du choix des instruments de politique energetique canadienne a des fins environnementales de 1993 a nos jours

    Science.gov (United States)

    Fathy El Dessouky, Naglaa

    Au cours de la derniere decennie, les modes de la gouvernance ont pris place dans un contexte totalement different de celui qu'ils avaient auparavant. Les gouvernements modernes se rendent compte qu'ils perdent de plus en plus leur capacite a elaborer et a gerer les changements d'une maniere autonome. Ainsi, les fonctions et les activites traditionnellement accomplies exclusivement par le gouvernement engagent de nos jours une gamme d'acteurs etatiques et non etatiques. A l'encontre du concept traditionnel de l'Etat controleur, la gouvernance contemporaine est ainsi devenue moins une question d'offre de service et davantage une gestion indirecte des reseaux de politique publique. Dans cette entreprise, les gouvernements contemporains, cherchant plus d'information, de soutien et de legitimite en matiere de formulation des decisions, ont besoin d'etablir des relations avec les divers groupes d'interet qui, a leur tour, voulaient plus de promotion et de protection en faveur de leurs interets a travers leur implication au processus de l'elaboration et de la mise en oeuvre des politiques publiques. Ainsi, l'approche des reseaux de politique publique represente aujourd'hui un courant considerable au sein du champ d'analyse des politiques publiques. Toutefois, les preoccupations des chercheurs pour cette approche, dans le domaine des politiques energetiques a des fins environnementales, semblent recentes, et les etudes realisees sont encore trop peu nombreuses. Au Canada, au debut des annees 1990, le gouvernement ainsi que plusieurs groupes d'interets, des differents secteurs energetique, industriel et environnemental, ont commence a intensifier leurs efforts pour s'attaquer au probleme du changement climatique d'origine energetique, genere surtout par le secteur de l'industrie. Au cours de la derniere decennie, la question touchant plutot le sujet du developpement energetique durable represente le plus important domaine des politiques publiques ayant surgi recemment dans

  15. Modelisation des effets physico-techniques pour la conception des ...

    African Journals Online (AJOL)

    automatisation dans les installations industrielles a besoin d'une régulation automatique des commandes des processus technologiques pour lesquelles certaines contraintes sont à relever compte tenu des exigences des innovations scientifiques de ...

  16. Possibility of applying the gamma-gamma method to the in situ determination of uranium-ore densities; Les possibilites d'application de la methode gamma-gamma a la determination en place de la densite des minerais d'uranium

    Energy Technology Data Exchange (ETDEWEB)

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

    1965-07-01

    The principles of the gamma-gamma method are reviewed. It is shown in particular that, under certain conditions, the method makes it possible to obtain a representative measurement of the electronic density. Chemical analyses have been carried out on samples obtained from uranium deposits. The results show that an exact correlation exists between the massive and electronic densities. It is possible to consider the possibility of measuring the density of uranium-containing rocks by the gamma-gamma method. (authors) [French] Les principes de la methode gamma-gamma sont rappeles. En particulier, il est montre que, dans certaines conditions, la methode permet une mesure representative de la densite electronique. Des analyses chimiques ont ete effectuees sur des echantillons provenant de gisements uraniferes. Les resultats indiquent qu'il existe une correlation precise entre leur densite massique et leur densite electronique. Il est possible d'envisager la mesure de la densite des roches uraniferes par la methode gamma-gamma.

  17. Estimation of the energy needs; Estimation des besoins energetiques

    Energy Technology Data Exchange (ETDEWEB)

    Ailleret, [Electricite de France (EDF), Dir. General des Etudes de Recherches, 75 - Paris (France)

    1955-07-01

    The present report draws up the balance on the present and estimable energy consumption for the next twenty years. The present energy comes mainly of the consumption of coal, oil products and essentially hydraulic electric energy. the market development comes essentially of the development the industrial activity and of new applications tributary of the cost and the distribution of the electric energy. To this effect, the atomic energy offers good industrial perspectives in complement of the energy present resources in order to answer the new needs. (M.B.) [French] Le present rapport dresse le bilan sur la consommation energetique actuelle et previsionnelle pour les vingt prochaines annees. L'energie actuelle provient principalement consommation de charbon, de produits petroliers et d'energie electrique essentiellement hydraulique. l'evolution du marche provient essentielement du developpement l'activite industriel et de nouvelles applications tributaire du cout et de la distribution de l'energie electrique. A cet effet, l'energie atomique offre de bonne perspectives industrielles en complement des sources actuelles energetiques afin de repondre aux nouveaux besoins. (M.B.)

  18. Contribution to the electrothermal simulation in power electronics. Development of a simulation methodology applied to switching circuits under variable operating conditions; Contribution a la simulation electrothermique en electronique de puissance. Developpement d`une methode de simulation pour circuits de commutation soumis a des commandes variables

    Energy Technology Data Exchange (ETDEWEB)

    Vales, P.

    1997-03-19

    In modern hybrid or monolithic integrated power circuits, electrothermal effects can no longer be ignored. A methodology is proposed in order to simulate electrothermal effects in power circuits, with a significant reduction of the computation time while taking into account electrical and thermal time constants which are usually widely different. A supervising program, written in Fortran, uses system call sequences and manages an interactive dialog between a fast thermal simulator and a general electrical simulator. This explicit coupling process between two specific simulators requires a multi-task operating system. The developed software allows for the prediction of the electrothermal power dissipation drift in the active areas of components, and the prediction of thermally-induced coupling effects between adjacent components. An application to the study of hard switching circuits working under variable operating conditions is presented

  19. Current algebra; Algebre des courants

    Energy Technology Data Exchange (ETDEWEB)

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

    1967-07-01

    The first three chapters of these lecture notes are devoted to generalities concerning current algebra. The weak currents are defined, and their main properties given (V-A hypothesis, conserved vector current, selection rules, partially conserved axial current,...). The SU (3) x SU (3) algebra of Gell-Mann is introduced, and the general properties of the non-leptonic weak Hamiltonian are discussed. Chapters 4 to 9 are devoted to some important applications of the algebra. First one proves the Adler- Weisberger formula, in two different ways, by either the infinite momentum frame, or the near-by singularities method. In the others chapters, the latter method is the only one used. The following topics are successively dealt with: semi leptonic decays of K mesons and hyperons, Kroll- Ruderman theorem, non leptonic decays of K mesons and hyperons ( {delta}I = 1/2 rule), low energy theorems concerning processes with emission (or absorption) of a pion or a photon, super-convergence sum rules, and finally, neutrino reactions. (author) [French] La premiere partie de ce cours (trois premiers chapitres), traite des generalites concernant l'algebre de courants. Apres une definition rapide des courants faibles et un rappel de leurs proprietes (hypothese V-A, conservation du courant vecteur, regles de selection, courant axial partiellement conserve,...), l'on introduit l'algebre de Gell-Mann SU (3) x SU (3), et discute les proprietes generales de l'Hamiltonien faible non leptonique. Les chapitres IV a IX sont consacres a des applications importantes de l'algebre des courants. En premier lieu l'on demontre la formule de Adler et Weisberger, par deux methodes differentes, celle dite du repere de moment infini et celle des singularites proches. Cette derniere est seule utilisee dans la suite. Puis, l'on traite successivement les problemes suivants: desintegrations semi-leptoniques des mesons K et des hyperons, theoreme de Kroll-Ruderman, desintegrations non leptoniques des mesons

  20. Some types of difficulty encountered during the simulation of heat exchangers (1961); Quelques types de difficultes rencontrees lors de la simulation des echangeurs (1961)

    Energy Technology Data Exchange (ETDEWEB)

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

    1961-07-01

    After recalling that the simulation of exchangers poses problems which are often difficult to solve, the author points out that these problems appear first of all when the physical phenomena are described in terms of equations. They appear also during the solving of the equations since expressions which are more and more complex can give rise to unstable electronic structures. These difficulties are developed during the analysis of various types of exchangers and in each case the solutions chosen are given. (author) [French] On rappelle que la simulation des echangeurs pose un certain nombre de problemes souvent difficiles a resoudre. Les difficultes apparaissent d'abord lors de la mise en equations des phenomenes physiques; elles apparaissent ensuite au moment de la resolution, car des formulations de plus en plus complexes peuvent donner lieu a des structures electroniques instables. On developpe ces difficultes en faisant l'analyse de quelques types varies d'echangeurs et l'on indique dans chacun des cas les solutions qui ont ete retenues. (auteur)

  1. variabilite des productions et des revenus des exploitations

    African Journals Online (AJOL)

    3Centre de coopération internationale en recherche agronomique pour le développement (CIRAD), UMR Innovation,. Montpellier, France. Doubangolo COULIBALY, Email kone_b@yahoo.fr. RESUME. La durabilité des systèmes de production à base de coton dans un contexte de variabilité des prix aux producteurs et de ...

  2. Production of artificial radioelements; Production des radioelements artificiels

    Energy Technology Data Exchange (ETDEWEB)

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

    1960-07-01

    The techniques used in the production of artificial radioelements are described, with special emphasis on the following points: - nuclear reactions and use of reactors; - chemical separation methods and methods for enriching the activity of preparations; - protection of personnel and handling methods. (author) [French] On decrit l'ensemble des techniques utilisees dans la fabrication des radioelements artificiels en insistant notamment sur les points suivants: - reactions nucleaires et utilisation des reacteurs; - methodes de separations chimiques et methodes d'enrichissement d'activite des preparations; - protection du personnel et methodes de manipulation. (auteur)

  3. Using XML to encode TMA DES metadata

    Directory of Open Access Journals (Sweden)

    Oliver Lyttleton

    2011-01-01

    Full Text Available Background: The Tissue Microarray Data Exchange Specification (TMA DES is an XML specification for encoding TMA experiment data. While TMA DES data is encoded in XML, the files that describe its syntax, structure, and semantics are not. The DTD format is used to describe the syntax and structure of TMA DES, and the ISO 11179 format is used to define the semantics of TMA DES. However, XML Schema can be used in place of DTDs, and another XML encoded format, RDF, can be used in place of ISO 11179. Encoding all TMA DES data and metadata in XML would simplify the development and usage of programs which validate and parse TMA DES data. XML Schema has advantages over DTDs such as support for data types, and a more powerful means of specifying constraints on data values. An advantage of RDF encoded in XML over ISO 11179 is that XML defines rules for encoding data, whereas ISO 11179 does not. Materials and Methods: We created an XML Schema version of the TMA DES DTD. We wrote a program that converted ISO 11179 definitions to RDF encoded in XML, and used it to convert the TMA DES ISO 11179 definitions to RDF. Results: We validated a sample TMA DES XML file that was supplied with the publication that originally specified TMA DES using our XML Schema. We successfully validated the RDF produced by our ISO 11179 converter with the W3C RDF validation service. Conclusions: All TMA DES data could be encoded using XML, which simplifies its processing. XML Schema allows datatypes and valid value ranges to be specified for CDEs, which enables a wider range of error checking to be performed using XML Schemas than could be performed using DTDs.

  4. Using XML to encode TMA DES metadata

    Science.gov (United States)

    Lyttleton, Oliver; Wright, Alexander; Treanor, Darren; Lewis, Paul

    2011-01-01

    Background: The Tissue Microarray Data Exchange Specification (TMA DES) is an XML specification for encoding TMA experiment data. While TMA DES data is encoded in XML, the files that describe its syntax, structure, and semantics are not. The DTD format is used to describe the syntax and structure of TMA DES, and the ISO 11179 format is used to define the semantics of TMA DES. However, XML Schema can be used in place of DTDs, and another XML encoded format, RDF, can be used in place of ISO 11179. Encoding all TMA DES data and metadata in XML would simplify the development and usage of programs which validate and parse TMA DES data. XML Schema has advantages over DTDs such as support for data types, and a more powerful means of specifying constraints on data values. An advantage of RDF encoded in XML over ISO 11179 is that XML defines rules for encoding data, whereas ISO 11179 does not. Materials and Methods: We created an XML Schema version of the TMA DES DTD. We wrote a program that converted ISO 11179 definitions to RDF encoded in XML, and used it to convert the TMA DES ISO 11179 definitions to RDF. Results: We validated a sample TMA DES XML file that was supplied with the publication that originally specified TMA DES using our XML Schema. We successfully validated the RDF produced by our ISO 11179 converter with the W3C RDF validation service. Conclusions: All TMA DES data could be encoded using XML, which simplifies its processing. XML Schema allows datatypes and valid value ranges to be specified for CDEs, which enables a wider range of error checking to be performed using XML Schemas than could be performed using DTDs. PMID:21969921

  5. 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

  6. Dislocational Rock Mechanisms As a Basis for Seismic Methods in the Search for Hydrocarbons La géomécanique de dislocation en tant que base des méthodes sismiques de la recherche des hydrocarbures

    Directory of Open Access Journals (Sweden)

    Pissetski V. B.

    2006-11-01

    exploration with the best objectivity. L'analyse des données géologo-géophysiques, en premier lieu, nous conforte dans l'idée de la faiblesse et de l'insuffisance des conceptions classiques du milieu sédimentaire continu stratifié et, en deuxième lieu, permet d'avancer une série d'idées physiques clés. La logique générale de la formulation de la conception proposée dans ce travail peut être présentée de la façon suivante : - le caractère discret nettement exprimé du processus de sédimentation permet d'affirmer qu'au moment des changements de cycles (pauses ou des événements sédimentaires dans le milieu, il se forme des couches fines ou des surfaces qui, plus tard, constituent des structures régulières de défaut de solidité ; - les changements de charge gravitationnels ou tectoniques mettent en action des mécanismes de destruction dont le développement régulier conduit à passer d'un système continu stratifié avec défaut à un système discret ; - le mécanisme de destruction discret est un processus final : chaque élément discret est limité dans l'espace par des surfaces horizontales et verticales de rupture de la continuité (dislocations atteignant un empilement critique final doué de la faculté d'un haut degré de réaction à n'importe quelle modification du bilan des charges mécaniques. Si du point de vue de cette conception, on effectue une analyse des données factuelles (affleurements et puits, on peut voir une concordance objective entre la structure de fissuration réelle et les principales limites temporelles et événementielles du processus de sédimentation. Les principales règles de la mécanique de destruction des milieux à défauts sont bien reconstitués en condition de laboratoire sur des modèles physiques fabriqués selon le principe du remplissage successif de la matière par la méthode couches sur couchesavec des arrêts pour la cristallisation. L'analyse théorique de l'état de contraintes des milieux discrets

  7. The thermodynamic approach of the pilot-scale purification of refractory metals; Application de la thermodynamique a la mise au point des methodes de purification industrielle des metaux et semi-metaux refractaires

    Energy Technology Data Exchange (ETDEWEB)

    Accary, A [Commissariat a l' Energie Atomique, Dir. des Piles Atomiques, Saclay (France). Centre d' Etudes Nucleaires

    1967-06-15

    The author shows how the thermodynamic can be applied to the prediction of the evolution of impurities from a metal or an alloy being melted and cast at the pilot-scale using electron bombardment and continuous casting in a water cooled copper. He studies this possibility on two examples: - the melting vanadium, - the melting of the uranium monocarbide. He shows using only the constants available in the literature and a few special runs in the pilot-equipment itself it is possible to determine: - the possibility of elimination of anyone impurity by keeping the material in the melting state under vacuum as well as the limit of purification which is achievable under given technological conditions, - the proportion of an impure metal which should be vaporized in order to bring the level of a given impurity down to a predetermined level and the necessary duration of heating. (author) [French] L'auteur montre comment la thermodynamique peut etre appliquee a la prevision de l'evolution d'un metal ou d'un alliage fondu a l'echelle pilote par bombardement d'electrons et coule en continu dans un creuset de cuivre refroidi. Il etudie cette possibilite sur deux cas particuliers: - la fusion de vanadium, - la fusion du monocarbure d'uranium. Il montre que, grace aux constantes disponibles dans la litterature et a des essais simples faits a l'aide de l'appareillage pilote lui-meme, on peut determiner: - la possibilite d'eliminer une impurete par maintien a l'etat fondu ainsi que la limite de purification dans des conditions technologiques donnees, - la proportion d'un metal brut qu'il faut evaporer pour amener sa teneur en une impurete a un niveau donne ainsi que la duree de chauffage necessaire, - la nature des additions propres a favoriser le depart d'une impurete et l'efficacite comparee des additions possibles. (auteur)

  8. Measurement of a neutral particle flux by a thermal method using the junction temperature effect; Mesure d'un flux de particules neutres par une methode thermique mettant a contribution l'effet de temperature des jonctions

    Energy Technology Data Exchange (ETDEWEB)

    Caron, Anthime [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires. Services Scientifiques

    1966-07-01

    Among all the methods suitable for measuring neutral particle fluxes obtained by proton charge exchange in an organic gas, the thermal method has been chosen. The energy imparted by the neutral particles to the target in the form of heat leads to the latter temperature increasing; this temperature is usually followed with a thermocouple. In order to increase the sensitivity and the elegance of the apparatus the thermocouple has been replaced by a junction whose characteristics are known to vary with temperature. A calibration is carried out using a beam of charged particles. The response obtained is linear. Measurements have been made with a power of up to 1 mW; the accuracy increases with the energy provided; for 4 joules an accuracy of 10 per cent is obtained. The apparatus may be improved in particular by extending the measurement range towards low power values, and by increasing the accuracy. (author) [French] Parmi toutes les methodes utilisees pour la mesure d'un flux de particules neutres, obtenues par echange de charge de protons dans un gaz organique, nous avons choisi la methode thermique. L'energie cedee par les particules neutres a la cible sous forme de chaleur provoque une elevation de temperature de celle-ci; cette temperature est habituellement reperee par thermocouple. Pour accroitre la sensibilite et la finesse de l'appareillage, nous avons substitue au thermocouple une jonction dont on sait que les caracteristiques varient avec la temperature. Un etalonnage est realise par un faisceau de particules chargees. La reponse obtenue est lineaire. Des puissances de l'ordre du mW ont ete mesurees; la precision croit avec l'energie apportee; elle est de 10 pour cent quand celle-ci est de 4 joules. L'appareillage peut etre notablement perfectionne, pour reculer la gamme des mesures vers les basses puissances et accroitre la precision. (auteur)

  9. Survey of Pulsed Neutron Source Methods for Multiplying Media; Methodes des Neutrons Pulses Pour l'Etude des Milieux Multiplicateurs; Obzor metodov s ispol'zovaniem istochnikov impul'snykh nejtronov dlya razmnozhayushchej sredy; Estudio Panoramico de los Metodos de Empleo de Fuentes de Neutrons Pulsados en Medios Multiplicadores

    Energy Technology Data Exchange (ETDEWEB)

    Garelis, E. [General Electric Company, Vallecitos Atomic Laboratory, Pleasanton, CA (United States)

    1965-10-15

    . Thus, this makes it possible to apply the methods developed for the repetitive to that of the pseudo-random technique. (author) [French] Depuis quelques annees, il existe deux opinions sur la maniere la plus efficace de mesurer la reactivite d'arret au moyen de generateurs de neutrons puises, savoir: a) les mesures classiques au moyen d'une source puisee a repetition; b) des methodes qui sont fondees sur la reponse a des impulsions pseudo-aleatoires et utilisent une correlation entre l'entree et la sortie. Dans les deux cas, les renseignements pertinents que l'on obtient sont identiques, en d'autres termes, idealement les deux methodes servent a determiner la fonction de reponse. L'auteur retrace l'evolution des methodes de mesure de la reactivite fondees sur les sources puisees dans les systemes a neutrons thermiques, depuis les premieres tentatives de Sjoestrand jusqu'a la recente methode de (k{beta}/ Script-Small-L ). Dans la methode habituelle, la fonction de Green relative a l'assemblage sous-critique - la reponse du reacteur a une source de neutrons a fonction delta - constitue la propriete recherchee. La decroissance exponentielle, exp(-{alpha}t), de la fonction de Green donne une constante de decroissance des neutrons instantanes independante du lieu. L'auteur examine les methodes permettant de deduire la reactivite de la mesure de a , par exemple, la mesure de a a l'etat critique retarde et la recente methode de (k{beta}/ Script-Small-L ). Il etudie notamment les traitements du mode fondamental a la lumiere de la theorie des methodes des neutrons puises, telles qu'elle a ete mise au point pour le modele (k{beta}/ Script-Small-L )- L'auteur examine les incidences de la theorie des neutrons puises en vue d'obtenir des constantes de decroissance precises et les donnees voulues pour l'analyse des systemes puises. Il passe en revue les travaux experimentaux qui font ressortir a la fois les avantages et les limitations de la technique de (k{beta}/ Script

  10. Intensity modulation in breast radiotherapy: Development of an innovative field-in-field technique at Institut Gustave-Roussy; Modulation d'intensite en radiotherapie mammaire: developpement d'une methode innovante de champ dans le champ a l'institut Gustave-Roussy

    Energy Technology Data Exchange (ETDEWEB)

    Heymann, S.; Bourhis, J.; Bourgier, C. [Departement d' oncologie radiotherapie, institut de cancerologie Gustave-Roussy, 114, rue edouard-Vaillant, 94805 Villejuif (France); Verstraet, R.; Pichenot, C.; Vergne, E.; Lefkopoulos, D. [Departement de physique, institut de cancerologie Gustave-Roussy, 114, rue edouard-Vaillant, 94805 Villejuif (France); Husson, F.; Kafrouni, H.; Mahe, J.; Kandalaft, B. [Societe Dosisoft, 45/47, avenue Carnot, 94230 Cachan (France); Marsiglia, H. [Departement d' oncologie radiotherapie, institut de cancerologie Gustave-Roussy, 114, rue edouard-Vaillant, 94805 Villejuif (France); Universite de Florence, Florence (Italy)

    2011-12-15

    Purpose. - To assess the potential dosimetric gain of pre-segmentation modulated radiotherapy (OAPS, DosiSoft{sup TM}) of breast, compared to routine 3D conformal radiotherapy. Patients and methods. - Twenty patients treated with conservative surgery for breast cancer (9 right and 11 left sided) with various breast volume (median 537 cm{sup 3}; range [100-1049 cm{sup 3}]) have been selected. For each patient, we have delineated a breast volume and a compensation volume (target volumes), as well as organs at risk (lungs and heart). Two treatment plans have been generated: one using the routine 3D conformal technique and the other with the pre-segmentation algorithm of DosiSoft{sup TM} (OAPS). The dose distribution were analyzed using the conformity index for target volumes, mean dose and V 30 Gy for the heart, and mean dose, V 20 Gy and V 30 Gy for lungs. Results. - Over the 20 patients, the conformity index increased from 0.897 with routine technique to 0.978 with OAPS (P < 0,0001). For heart and lung, OAPS decreased irradiation (mean cardiac dose 1,3 vs 1,6 Gy [P < 0,0001] and pulmonary V 20 Gy 6,6 vs 7,1 [P < 0,0001]). Conclusion. - OAPS (DosiSoft{sup TM}) is an original method of segmentation of breast. It is automatic, fast and easy, and is able to increase the conformity index, while sparing organ at risk. (authors)

  11. Study of the anodic process in the electrolysis of molten chlorides. Application to the chlorine electrode; Contribution a l'etude du processus anodique dans l'electrolyse des chlorures fondus. Application a l'electrode de chlore

    Energy Technology Data Exchange (ETDEWEB)

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

    1967-05-01

    propriete de la reaction d'oxydation des ions Cl{sup -} nous a permis de proposer une methode electrochimique pour l'etude de l'equilibre d'absorption du chlore entre une phase solide et une phase liquide. Nous pouvons, en effet, remplacer l'apport exterieur de chlore sous une pression P par une electrolyse sous une densite de courant I. Nous avons developpe un schema qui rend compte de la cinetique de la reaction de decharge des ions Cl{sup -}. Il a ete verifie a l'aide des courbes intensite-potentiel et des courbes potentiel-temps caracterisant la depolarisation du carbone en circuit ouvert. Deux methodes ont ete utilisees pour la mesure de la quantite de chlore adsorbe sur le carbone. Les liaisons des molecules de chlore adsorbe sur le carbone et la surface d'echange electrode-electrolyte ont pu etre precisees en faisant varier la temperature, la nature de l'electrode et de l'electrolyte. Certaines anomalies et en particulier certains phenomenes transitoires, ont ete expliques par l'influence de l'oxygene present dans le sel fondu sous forme d'ions O{sup 2-} et a la surface de l'electrode, sous forme de complexes de chimisorption. (auteur)

  12. Spiral hydro-CT of the pancreas in the thin-slice method; Hydrospiral-CT des Pankreas in Duennschichttechnik

    Energy Technology Data Exchange (ETDEWEB)

    Richter, G.M. [Abt. fuer Radiodiagnostik, Radiologische Universitaetsklinik Heidelberg (Germany); Simon, C. [Abt. fuer Radiodiagnostik, Radiologische Universitaetsklinik Heidelberg (Germany)]|[Abt. Allgemeine Chirurgie, Chirurgische Universitaetsklinik Heidelberg (Germany); Hoffmann, V. [Abt. fuer Radiodiagnostik, Radiologische Universitaetsklinik Heidelberg (Germany); DeBernardinis, M. [Abt. fuer Radiodiagnostik, Radiologische Universitaetsklinik Heidelberg (Germany); Seelos, R. [Abt. Allgemeine Chirurgie, Chirurgische Universitaetsklinik Heidelberg (Germany); Senninger, N. [Abt. Allgemeine Chirurgie, Chirurgische Universitaetsklinik Heidelberg (Germany); Kauffmann, G.W. [Abt. fuer Radiodiagnostik, Radiologische Universitaetsklinik Heidelberg (Germany)

    1996-05-01

    151 konsekutive Patienten mit Verdacht auf Pankreastumor untersucht. Hydro-CT-Technik: Patientenlagerung in 30 RAO, Darmparalyse durch 40 mg Buscopan, Magen- und Duodenaldistension mittels 1,5 l Wasser oral, individualisierte Boluskinetik Spiral-CT mit 3 mm Inkrement, 6 mm Tischvorschub und 3 mm Rekonstruktion, 130 ml nichtionisches KM (5 ml/s). Folgende Punkte wurden festgehalten und bewertet: 1. Tumordetektion ja/nein; 2. Differenzierung eines festgestellten Tumors in maligne oder benigne an Hand festgelegter Kriterien; 3. computertomographische Differentialdiagnostik der Tumoren; 4. Beurteilung der Resektabilitaet. Bei positivem Tumornachweis wurde als Goldstandard die intraoperative und histologische Bewertung und bei negativem Tumornachweis eine 6 monatige tumorfreie Nachsorgeperiode festgelegt. Die Praevalenz einer Raumforderung des Pankreas betrug etwa 38% in der Gesamtgruppe. Dabei erreichte die Hydro-CT eine Gesamtgenauigkeit in der Tumordetektion von 97,4% bei einer Sensitivitaet von 100% und einer Spezifitaet von 95,9%. Bei der Differenzierung eines malignen versus eines benignen Tumors ergab sich eine Gesamtgenauigkeit von 89,7% bei einer Sensitivitaet von 92,5% und einer Spezifitaet von 83,3%. 58 Patienten wurden operiert. Die Gesamtgenauigkeit der Resektabilitaetsbeurteilung erreichte 95% bei einer Sensitivitaet von 90,5% und einer Spezifitaet von 100%. (orig./MG)

  13. A new method for characterizing super-insulators. Application to the identification of conduction modes; Nouvelle methode de caracterisation thermique des super-isolants. Application a l'identification des differents modes de conduction

    Energy Technology Data Exchange (ETDEWEB)

    Demange, D.; Bejet, M.; Laizet, J.C.

    2002-07-01

    In order to obtain thermal data necessary to the design of space systems, the ONERA developed a method to measure the thermal flux crossing an insulating structure under high thermal gradients. This method gives the thermal conductivity of material for an homogeneous composition of the structure. It allows the characterization of insulators under controlled atmosphere and at very high temperature, 2500 C. (A.L.B.)

  14. Influence des melanges complexes organiques sur le sort des dioxines et furanes: Implications dans le developpement de facteurs de caracterisation en analyse du cycle de vie

    Science.gov (United States)

    Taing, Eric

    The environmental fate of dioxins and furans, or polychlorodibenzo-p-dioxins and -furans (PCDD/Fs), leaching from wood poles treated with pentachlorophenol (PCP) oil is modified by the presence of oil. Interactions between co-contaminants, which also exist for other pollutants within the mixtures, were shown in the specific context of risk analysis, but have never been taken into account for the generic context of life cycle assessment (LCA). This decision-making tool relies on characterization factors (CF) to estimate the potential impacts of an emitted amount of a pollutant in different impact categories such as aquatic ecotoxicity and human toxicity. For these two impact categories, CFs are calculated from a cause-effect chain that models the environmental fate, exposure and effects of the pollutant (represented by a matrix of fate FF, exposure XF and effect EF, respectively), meaning that a modification of PCDD/Fs fate induces a change in PCDD/Fs CFs. The research question is therefore as follows: In life cycle impact assessment (LCIA), to what extent would the potential impacts of PCDD/Fs on aquatic ecotoxicity and human toxicity change when taking into account the influence of a complex organic mixture on PCDD/Fs fate?. Thus, the main objective is to develop CFs of PCDD/Fs when their fate is influenced by PCP oil and compare them with the CFs of PCDD/Fs without oil for the aquatic ecotoxicity and human toxicity impact categories. A mathematic approach is established to determine the new environmental distribution of PCDD/Fs in the presence of oil and a new FF' matrix is calculated from this new distribution to obtain new CFs' integrating oil influence. FF' and CF' are then compared to FF and CF of PCDD/Fs without the oil. Finally, potential (eco)toxic impacts of the PCDD/F Canadian emissions are calculated with the new CFs' of PCDD/Fs in presence of oil. By only focusing on the results for an emission into air, freshwater and natural soil on a continental scale, the overall elimination fractions of 2,3,7,8-TCDD changed significantly. For the three emissions, organic fractions increased the overall elimination fraction of 2,3,7,8-TCDD into the continental air compartment, induced by a higher volatility of organic fractions than 2,3,7,8-TCDD: for an emission into continental air, organic fractions increased the overall elimination fraction of 2,3,7,8-TCDD in the continental air from 29% to 49% at most. For an emission into continental freshwater, 2,3,7,8-TCDD fate was mainly influenced by two groups of organic fractions: the lightest ones that volatilize into continental air (overall elimination fraction of 2,3,7,8-TCDD increasing from 2% to 35%) and the heaviest ones that are removed by sedimentation (DTCDD,fwC,fwC from 87% up to 96%). Therefore, an approach has been proposed to represent the carrier behaviour of the oil for PCDD/Fs. PCDD/F potential impacts in aquatic ecotoxicity and human toxicity change in a range up to two orders of magnitude depending on the emitting compartment (except for the seawater and ocean compartments). As 2,3,7,8-TCDD is one of the most toxic pollutant, this changing is significant in LCA. To assess the validity of the model's result, it is recommended to carry out laboratory experiments on the PCDD/F volatilization with oil. In addition, it could be interesting to integrate the influence of PCP on PCDD/Fs fate and, more broadly, the influence of all cocontaminants on PCDD/Fs exposure and effects. Moreover having a unique CFeco and CF tox via a weighting of the 17 CF'eco and the 17 CF' tox, respectively, is necessary for a use in LCA. Unfortunately the variability of the composition makes the weighting difficult, so it is suggested to calculate the mean CF'eco and CF'tox. Finally this research could be carried out on other pollutants whose fate is known to be modified by a complex organic mixture in an effort to ensure that impact characterization better reflects reality. (Abstract shortened by UMI.).

  15. MODELES ET CALCUL DES SYSTEMES DE SUSPENSION MAGNETIQUE PASSIVE -DEVELOPPEMENTS ET CALCULS ANALYTIQUES EN 2D ET 3D DES INTERACTIONS ENTRE AIMANTS PERMANENTS-

    OpenAIRE

    Allag , Hicham

    2010-01-01

    The passive magnetic suspensions operate using attractive or repulsive forces exerted between permanent magnets. After giving an overview of different possible configurations of magnetic suspensions, the calculation of interactions between permanent magnets was developed. The calculations are realised for parallelepipeds magnets, where the magnetization is represented by distributions of charges or poles (Coulombian approach). All interactions (energy, forces, torques, etc ....) was calculate...

  16. System Identification for Integrated Aircraft Development and Flight Testing (l’Identification des systemes pour le developpement integre des aeronefs et les essais en vol)

    Science.gov (United States)

    1999-03-01

    aerodynamics to affect load motions. The effects include a load trail angle in proportion to the drag specific force, and modification of the load pendulum...equations algorithm for flight data filtering architeture . and data consistency checking; and SCIDNT 8, an output architecture. error identification...accelerations at the seven sensor locations, identified system is proportional to the number When system identification is performed, as of flexible modes

  17. Revetements nanostructures pour la protection des metaux dans les environnements marins

    Science.gov (United States)

    Brassard, Jean-Denis

    nanoparticules de ZnO enrobees de silane sont imbriquees dans le reseau nanostructure de silicone copolymerise. Le revetement C produit de cette facon satisfaisait a la norme ASTM d'adherence a un substrat, mais n'est pas superhydrophobe, restant seulement hydrophobe avec un angle de contact reduit de 123°. Tous les revetements optimises developpes montrent un niveau de resistance a la corrosion beaucoup plus eleve que leur substrat tant en polarisation qu'en impedance electrochimique. Toutefois aucune relation entre l'hydrophobicite et le niveau de resistance a la corrosion n'a ete etablie. Il a seulement ete determine que ce sont la nature chimique de l'interface, a savoir ses proprietes electriques en isolation, son hydrophobicite et la presence d'air, de meme que l'epaisseur qui sont les deux aspects essentiels a respecter pour avoir de bonnes proprietes anticorrosion. Les trois revetements A, B, et C ont ete evalues quant a la reduction d'adherence et d'accumulation evaluee dans les environnements givrants rencontres en mer arctique. En premiere position, le revetement superhydrophobe B avec un angle de contact de 154°et un facteur de reduction l'adherence (ARF) de la glace sur l'aluminium de 14 et de la quantite accumulee 5% moindre. En seconde position, le revetement superhydrophobe A avec un angle de contact de 155° et un facteur ARF de 6, lequel n'a pas ete evalue en accumulation; et en troisieme position le revetement hydrophobe C avec un facteur de reduction de 3, lequel ne reduit pas la masse de glace accumulee. Deux mecanismes ont ete trouves responsables de l'adherence a la glace sur les revetements developpes soient: 1. l'effet d'ancrage diminue par la presence de nanorugosites hydrophobes recouvrant les microrugosites pouvant adsorber de l'air et 2. L'effet de la quantite d'air adsorbe dans la structure de l'interface, a savoir que pour des angles de contact egaux, si la quantite d'air augmente dans la microstructure, donc un Rrms plus eleve, ferait que l

  18. Statutes of limitations: the special problem of DES suits

    International Nuclear Information System (INIS)

    Feigin, C.A.

    1981-01-01

    In 1971, medical studies determined that DES causes a rare type of vaginal cancer in a small number of daughters of mothers who took DES during pregnancy. Subsequently, medical studies determined that exposure to DES can cause other vaginal abnormalities in the daughters, some of which may be precancerous. As a result of these discoveries, many lawsuits have been filed by these daughters against DES manufacturers. Many DES suits may be barred by statutes of limitations, both because the number of years between the daughters' exposure to DES in utero and the discovery that DES can cause injuries exceeds the statutory period, and because the cancer or other injuries caused by DES may not develop for many additional years. This Note discusses two methods that DES plaintiffs may be able to use to overcome the potential statutes of limitations bar: the discovery rule, and state provisions which toll the statute of limitations for minors. The Note contends that courts should apply an expanded discovery rule to DES suits to avoid the unfair result of barring a claim before the plaintiff could have known that she had a cause of action. In addition, the Note argues that the injury which causes the statute of limitations to begin to run in DES suits should not be rigidly defined. Finally, the Note urges that courts allow eligible DES plaintiffs to take advantage of applicable state provisions that toll the statute of limitations for minors

  19. Deterministic methods for the relativistic Vlasov-Maxwell equations and the Van Allen belts dynamics; Methodes deterministes de resolution des equations de Vlasov-Maxwell relativistes en vue du calcul de la dynamique des ceintures de Van Allen

    Energy Technology Data Exchange (ETDEWEB)

    Le Bourdiec, S

    2007-03-15

    Artificial satellites operate in an hostile radiation environment, the Van Allen radiation belts, which partly condition their reliability and their lifespan. In order to protect them, it is necessary to characterize the dynamics of the energetic electrons trapped in these radiation belts. This dynamics is essentially determined by the interactions between the energetic electrons and the existing electromagnetic waves. This work consisted in designing a numerical scheme to solve the equations modelling these interactions: the relativistic Vlasov-Maxwell system of equations. Our choice was directed towards methods of direct integration. We propose three new spectral methods for the momentum discretization: a Galerkin method and two collocation methods. All of them are based on scaled Hermite functions. The scaling factor is chosen in order to obtain the proper velocity resolution. We present in this thesis the discretization of the one-dimensional Vlasov-Poisson system and the numerical results obtained. Then we study the possible extensions of the methods to the complete relativistic problem. In order to reduce the computing time, parallelization and optimization of the algorithms were carried out. Finally, we present 1Dx-3Dv (mono-dimensional for x and three-dimensional for velocity) computations of Weibel and whistler instabilities with one or two electrons species. (author)

  20. Civili, langue des Baloango

    DEFF Research Database (Denmark)

    Mavoungou, Paul Achille; Ndinga-Koumba-Binza, Hugues Steve

    , Congo, Angola, etc.) issus de la décolonisation. Il présente de façon succincte quelques phénomènes historiques, phonologiques, morphosyntaxiques, homonymiques et analogiques de la langue. Des faits sémantiques des emprunts linguistiques y sont également décrits dans le cadre des changements...

  1. Évaluation des propriétés antimicrobiennes des javels vendues à ...

    African Journals Online (AJOL)

    SARAH

    31 janv. 2016 ... 2 : Laboratoire de Chimie des Eaux, Facultés des Sciences (FDS) ... Evaluation of the antimicrobial properties of bleaches sold in Lomé on some bacteria ... Materials and Methods: This consisted of microbiological analysis of ...

  2. The industrial production of fuel elements; La fabrication en france des elements combustibles

    Energy Technology Data Exchange (ETDEWEB)

    Boussard, R [Commissariat a l' Energie Atomique, Fontenay-aux-Roses (France). Centre d' Etudes Nucleaires; Nadal, J [Societe Industrielle de Combustible Nucleaire (SICN), 75 - Paris (France); Pellen, A [Compagnie pour l' Etude et la Realisation de Combustibles Atomiques (CERCA), 75 - Paris (France)

    1964-07-01

    indiquent pourquoi et comment l'on est passe de la gaine filee a la gaine usinee et mentionnent quelques caracteristiques de l'appareillage utilise ainsi que les controles effectues. Ils donnent egalement quelques indications sur la fabrication et l'usinage des chemises. Apres avoir rappele comment se presente en France a la mi-1964 l'industrie des combustibles nucleaires, les auteurs insistent sur les aspects economiques de la fabrication des elements combustibles. Ils montrent l'importance relative des investissements sur le prix de revient du combustible proprement dit, dont ils examinent ensuite les differentes pertes. Ils font une analyse du prix de revient de l'element combustible complet en tirant les enseignements actuels. Pour conclure les auteurs indiquent les points particuliers sur lesquels doit porter l'action a venir pour diminuer le cout d'une fabrication assez delicate, mais maintenant bien au point, et supputent le developpement de cette branche industrielle nouvelle. 2eme Partie - FABRICATION INDUSTRIELLE DES ELEMENTS COMBUSTIBLES POUR REACTEURS DU TYPE PISCINE: Les auteurs indiquent comment a ete elude en France le probleme de la fabrication industrielle des elements combustibles obtenue par laminage et les trois phases par lesquelles on est passe: 1 - Assemblage des plaques fabriquees aux U.S.A., 2 - Laminage des noyaux fabriques aux U.S.A. pour obtenir les plaques, 3 - Elaboration de l'alliage U.Al et fabrication des noyaux. Ils rappellent ensuite brievement les caracteristiques des differents elements combustibles actuellement fabriques. Ils decrivent ensuite les differents stades de l'elaboration en donnant des indications sur l'appareillage et en insistant sur l'importance des controles effectues a chaque stade. Pour finir ils examinent le developpement futur de ce type de fabrication, compte tenu des ameliorations prevues ou envisageables. (auteurs)

  3. Studying Hostile, Deceptive, and Dangerous Surroundings: Report of a Workshop on Social Research Methods for Non-Permissive Environments (Etudier des Milieux Hostiles, Trompeurs et Dangereux - Rapport Concernant un Atelier sur les Methodes de Recherche Sociale an Milieu non Permissif)

    Science.gov (United States)

    2010-08-01

    personnel ont été employés comme « coordonnateurs des effets sur les humains » en utilisant l’observation directe et indirecte, des entrevues, des sondages...gaining access through the processes dictated by elites in the capital , a researcher still has to meet people on their own terms, go to them in the...flow adequacy, capital structure and asset protection, and liquidity. When we understand and apply both corporate and sovereign ratings, we can

  4. Inverse method for effects characterization from ultrasonic b-scan images; Caracterisation des defauts par une methode d'inversion lors d'un controle ultrasonore. Application au controle des defauts en paroi externe

    Energy Technology Data Exchange (ETDEWEB)

    Faur, M. [Paris-11 Univ., 91 - Orsay (France)

    1999-02-01

    In service inspections of French nuclear pressure water reactor vessels are carried out automatically in complete immersion from the inside by means of ultrasonic focused probes working in the pulse echo mode. Concern has been expressed about the capabilities of performing non destructive evaluation of the Outer Surface Defects (OSD), i.e. defects located in the vicinity of the outer surface of the inspected components. OSD are insonified by both a direct field that passes through the inner surface (water/steel) of the component containing the defect and a secondary field reflected from the outer surface. Consequently, the Bscan images, containing the signatures of such defects, are complicated and their interpretation is a difficult task. This work deals with extraction of the maximum available information for characterizing OSD from ultrasonic Bscan images. Our main objectives are to obtain the type of OSD and their geometric parameters by means of two specific inverse methods. The first method is used for the identification of the geometrical parameters of the equivalent planar OSD from segmented Bscan images. Ultrasonic equivalent defect sizing model-based methods may be used to size a defect in a material by obtaining a best-fit simple equivalent shape that matches the ultrasonic observed data. We illustrate the application of such an equivalent sizing OSD method that is based on a simplified direct model. The major drawback of this identification method, as used to date, is that only a part of the useful information contained into original Bscan image, i.e. segmented Bscan image, is used for defect characterization. Moreover, it requires the availability of defect classification information (i.e. if the defect is volumetric or planer, e. g. a crack or a lack of fusion), which, generally, may be as difficult to obtain as the defect parameters themselves. Therefore, we propose a parameter estimation method for extracting complementary information on the defect

  5. Des racines et des ailes

    Directory of Open Access Journals (Sweden)

    Stéphanie Vincent-Geslin

    2012-05-01

    Full Text Available Les mobilités pendulaires semblent être en augmentation en Europe depuis une dizaine d’années. Cette croissance du temps passé à se déplacer amène à remettre en question la conjecture de Zahavi et apparaît relativement inexplicable en regard du paradigme classique de l’acteur rationnel traditionnellement utilisé dans le champ des transports. Si, dans la littérature, les temps de déplacements sont principalement expliqués par le contexte résidentiel, la forme urbaine et le travail, ce cadre explicatif ne dit rien des processus de décision eux-mêmes qui amènent aux pendularités intensives.À partir d’une enquête qualitative menée auprès de pendulaires français, suisses et belges, cette contribution propose d’analyser les arbitrages et les éléments déterminants des processus de la grande pendularité. Les mobilités quotidiennes pendulaires apparaissent comme le résultat de compromis entre activité professionnelle, attachement résidentiel et choix de vie et prennent ainsi la forme de stratégies de conciliation entre vie privée et vie professionnelle. Ces mobilités spatiales permettent alors paradoxalement la préservation des ancrages résidentiels, sociaux et familiaux.Roots and wings. Long-distance commuting patterns, or how to conciliate professional and personal lifeLong-distance commuting patterns appear to be increasing in Europe over the last ten years. These raising mobility patterns lead to reappraise the Zahavi conjecture and appear largely inexplicable by the classical rational actor paradigm traditionally used in transportation research. In literature, commuting is mainly explained by residential contexts, urban forms and job. Nevertheless this theoretical frame says little about the decision-making processes themselves. Based on a qualitative survey conducted in three European countries - France, Belgium and Switzerland – among a population of high commuters, this paper proposes an analysis of

  6. Numerical analysis of resonances induced by s wave neutrons in transmission time-of-flight experiments with a computer IBM 7094 II; Methodes d'analyse des resonances induites par les neutrons s dans les experiences de transmission par temps de vol et automatisation de ces methodes sur ordinateur IBM 7094 II

    Energy Technology Data Exchange (ETDEWEB)

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

    1969-01-01

    Numerical analysis of transmission resonances induced by s wave neutrons in time-of-flight experiments can be achieved in a fairly automatic way on an IBM 7094/II computer. The involved computations are carried out following a four step scheme: 1 - experimental raw data are processed to obtain the resonant transmissions, 2 - values of experimental quantities for each resonance are derived from the above transmissions, 3 - resonance parameters are determined using a least square method to solve the over determined system obtained by equalling theoretical functions to the correspondent experimental values. Four analysis methods are gathered in the same code, 4 - graphical control of the results is performed. (author) [French] L'automatisation, sur ordinateur IBM 7094/II, de l'analyse des resonances induites par les neutrons s dans les experiences de transmission par temps de vol a ete accomplie en la decomposant selon un schema articule en quatre phases: 1 - le traitement des donnees experimentales brutes pour obtenir les transmissions interfero-resonnantes, 2 - la determination des grandeurs d'analyse a partir des transmissions precedentes, 3 - l'analyse proprement dite des resonances dont les parametres sont obtenus par la resolution d'un systeme surabondant. Quatre methodes d'analyse sont groupees en un meme programme, 4 - la procedure de verification graphique. (auteur)

  7. Numerical analysis of resonances induced by s wave neutrons in transmission time-of-flight experiments with a computer IBM 7094 II; Methodes d'analyse des resonances induites par les neutrons s dans les experiences de transmission par temps de vol et automatisation de ces methodes sur ordinateur IBM 7094 II

    Energy Technology Data Exchange (ETDEWEB)

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

    1969-01-01

    Numerical analysis of transmission resonances induced by s wave neutrons in time-of-flight experiments can be achieved in a fairly automatic way on an IBM 7094/II computer. The involved computations are carried out following a four step scheme: 1 - experimental raw data are processed to obtain the resonant transmissions, 2 - values of experimental quantities for each resonance are derived from the above transmissions, 3 - resonance parameters are determined using a least square method to solve the over determined system obtained by equalling theoretical functions to the correspondent experimental values. Four analysis methods are gathered in the same code, 4 - graphical control of the results is performed. (author) [French] L'automatisation, sur ordinateur IBM 7094/II, de l'analyse des resonances induites par les neutrons s dans les experiences de transmission par temps de vol a ete accomplie en la decomposant selon un schema articule en quatre phases: 1 - le traitement des donnees experimentales brutes pour obtenir les transmissions interfero-resonnantes, 2 - la determination des grandeurs d'analyse a partir des transmissions precedentes, 3 - l'analyse proprement dite des resonances dont les parametres sont obtenus par la resolution d'un systeme surabondant. Quatre methodes d'analyse sont groupees en un meme programme, 4 - la procedure de verification graphique. (auteur)

  8. Complexation studies of actinides (U, Pu, Am) with linear polyamino-carboxylate ligands and sidero-chelates; Etudes de la chelation d'actinides (U, Pu, Am) par des ligands polyaminocarboxylate lineaires et des siderochelates d'interet environnemental

    Energy Technology Data Exchange (ETDEWEB)

    Nguyen, L.V.

    2010-11-25

    As part of our research endeavour aimed at developing and improving decontamination processes of wastewater containing alpha emitters, physico-chemical complexation studies of actinides (U, Pu, Am) with organic open-chain ligands such as poly-aminocarboxylic acids (H{sub 4}EDTA) and sidero-chelates (di-hydroxamic acids and desferrioxamine B) have been carried out. Gaining a clear understanding of the coordination properties of the targeted actinides is an essential step towards the selection of the most appropriate chelating agents that will exhibit high uptake efficiencies. EXAFS (Extended X-ray Absorption Fine Structure) measurements at the ESRF synchrotron enabled to elucidate the coordination scheme of uranium and plutonium complexes. Solution thermodynamic investigations were intended to provide valuable information about the nature and the stability of the uranium(VI) and americium(III) complexes prevailing at a given pH in solution. The set of stability constants determined from potentiometric and UV-visible spectrophotometric titrations, allowed to predict the speciation of the selected actinides in presence of the aforementioned ligands and to determine the pH range required for achieving 'ultimate' decontamination. (author) [French] Dans le cadre du developpement et de l'amelioration des procedes de decontamination d'effluents aqueux contamines par des radioelements emetteurs alpha, des etudes physico-chimiques sur la complexation des actinides (U, Pu, Am) avec des ligands organiques tels que des acides polyaminocarboxyliques lineaires (H{sub 4}EDTA) et des siderochelates (acides dihydroxamiques et desferrioxamine B) ont ete effectuees. La comprehension des proprietes de coordination est une etape essentielle pour selectionner les meilleurs agents chelatants qui se montreront efficaces dans le traitement des effluents. Les schemas de coordination des complexes d'uranium et de plutonium avec ces ligands ont ete determines a l

  9. Set up of a method for the adjustment of resonance parameters on integral experiments; Mise au point d`une methode d`ajustement des parametres de resonance sur des experiences integrales

    Energy Technology Data Exchange (ETDEWEB)

    Blaise, P.

    1996-12-18

    Resonance parameters for actinides play a significant role in the neutronic characteristics of all reactor types. All the major integral parameters strongly depend on the nuclear data of the isotopes in the resonance-energy regions.The author sets up a method for the adjustment of resonance parameters taking into account the self-shielding effects and restricting the cross section deconvolution problem to a limited energy region. (N.T.).

  10. Evaluation 2000 and regulation and method. Release monitoring and environmental surveillance around Cea centers; Bilan 2000 et reglementation et methode. Controle des rejets et surveillance de l'environnement des centres CEA

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-06-01

    This publication counts for the year 2000 for the evaluation of liquid and gaseous radioactive effluents releases and the radioactivity levels measured in the vicinity of Cea centers, through the air, water, vegetation and milk surveillance. An analysis of the results from 1996 to 2000 allows to follow their evolution. A second booklet develops the sampling and measurement methods made on effluents in environment. It present besides the regulation applied to effluents monitoring. (N.C.)

  11. Calculation of transient overvoltages in a 145-kV-cable termination by using the FDTD-method; Feldstaerkenberechnung bei transienten Spannungen an einem 145-kV-Endverschluss mit Hilfe des FDTD-Verfahrens

    Energy Technology Data Exchange (ETDEWEB)

    Gerhard, G.; Ioffe, A. [Gerhard-Mercator-Univ.-GH Duisburg (Germany). Fachgebiet Elektrische Energieuebertragung

    1997-10-20

    The transient electromagnetic field occured from the overvoltages in a slip-on cable termination was calculated by using the FDTD-method. The electric field strength in a gap between the cable shield and the stress cone was studied. (orig.) [Deutsch] Mit Hilfe des FDTD-Feldberechnungsverfahrens wird das transiente elektromagnetische Feld in einem Aufschiebeendverschluss untersucht, wobei ein Luftspalt zwischen den leitenden Teilen der Kabelader und dem Feldsteuerelement beruecksichtigt wird. (orig.)

  12. Possibilities for using a temperature-controlled pyrolysis method in order to determine the bonding form of mecury in soils and sediments; Moeglichkeiten der Anwendung eines temperaturgesteuerten Pyrolyseverfahrens zur Bestimmung der Bindungsform des Quecksilbers in Boeden und Sedimenten

    Energy Technology Data Exchange (ETDEWEB)

    Biester, H.

    1994-12-31

    The bonding behaviour of mercury in solids was investigated by means of a temperature-controlled pyrolysis method. Starting from the special property of elemental mercury to evaporate already at room temperature, a method was developed which permits to characterize different mercury bonding forms on the basis of Hg evaporation behaviour from solids at continuously increased temperature. The method starts from the assumption that it is possible to thermally reduce compounded mercury and release it in elemental form. The focus of the work was on the study of Hg bonding behaviour in soils and sediments. The soil samples used were from the areas of two mercury deposits, different kyanizing sites, some former mirror factories, and a chlor-alkali electrolysis workshop. The investigated sediments are a collection of mercury-polluted samples from the rivers Elbe, Rhine, Murg, the Rio Sao Joao de Meriti (Brazil) and some brooks and rivers of the Saar-Nahe depression. (orig./EF) [Deutsch] In der vorliegenden Arbeit wurde das Bindungsverhalten von Quecksilber in Feststoffen mittels eines temperaturgesteuerten Pyrolyseverfahrens untersucht. Ausgehend von der besonderen Eigenschaften des elementaren Quecksilbers, bereits bei Zimmertemperatur zu verdampfen, wurde ein Verfahren entwickelt, das eine Charakterisierung verschiedener Quecksilberbindungsformen aufgrund des Abdampfverhaltens des Hg aus dem Feststoff unter kontinuierlicher Temperaturerhoehung zulaesst. Dem Verfahren liegt dabei die Annahme zugrunde, dass sich das Quecksilber in seinen Verbindungen thermisch reduzieren und in elementarer Form freisetzen laesst. Durch den kontinuierlichen Aufheizprozess erfolgt die Freisetzung des Quecksilbers in Abhaengigkeit von der Bindungsstaerke in unterschiedlichen Temperaturbereichen. Die Darstellung der Ergebnisse erfolgte in Form von Abdampfkurven, die die Extinktion in Abhaengigkeit von der Temperatur darstellen. Der Schwerpunkt dieser Arbeit lag auf der Untersuchung des

  13. [FR] Le developpment du Travail Social et le pluralisme au Québec

    Directory of Open Access Journals (Sweden)

    André Jacob

    2011-06-01

    Full Text Available Normal 0 21 false false false ES X-NONE X-NONE MicrosoftInternetExplorer4 Au Canada et au Québec, traiter des questions liées à la diversité culturelle et au racisme a été un défi pour les gouvernements depuis les années soixante. Auparavant et jusqu'à présent, une grande partie des responsabilités en termes de développement ethnoculturel sensible des services publics (services sociaux, des programmes de formation en travail social, etc. ont été laissés aux mains d’organismes de charité non-lucratifs. Cependant, peu à peu, depuis les années soixante, le gouvernement fédéral et le gouvernement provincial, ont dû développer des politiques et des programmes d'action. Au Québec, le travail social a fait partie du débat face à deux grands courants politiques, l’un canadien basé sur le multiculturalisme, et l’autre québécois basé sur l'interculturalisme. L'article vise à donner une perspective historique

  14. Evaluation of the radiosensitivity of acute myeloblastic leukaemia progenitor cells by culture methods exploring self-renewal. Evaluation de la radiosensibilite des progeniteurs de leucemie aigue myeloblastique par des methodes de culture explorant ou non l'autorenouvellement

    Energy Technology Data Exchange (ETDEWEB)

    Cowen, D; Richaud, P; Landriau, S; Lagarde, P; Gualde, N [Fondation Bergonie, 33 - Bordeaux (France); Boiron, J M [Hopital du Haut-Leveque, 33 - Pessac (France); Mahon, F X; Belloc, F [Hopital Regional, 33 - Bordeaux (France); Reiffers, J [Hopital du Haut-Leveque, 33 - Pessac (France) Hopital Regional, 33 - Bordeaux (France)

    1993-01-01

    The progenitor cells of acute myeloblastic leukaemia (AML) are usually cultured in methylcellulose which selects for terminal dividing cells. Suspension cultures have been developed because they reflect self-renewal: the exponential growth of the progenitors of AML cultured in suspension is due to self-renewal. We have compared the radiosensitivity of the progenitors of AML grown either in methylcellulose alone or first in suspension for 7 days before being plated in methylcellulose. Cells were harvested from leukaemic bone marrows at the moment of diagnosis. The myeloblastic lineage of the colonies was assessed by morphological, cytochemical and immunophenotypic analysis and by the use of growth factors which do not stimulate T-lymphocytes. The cell-cycle distribution of leukaemic blasts was comparable for all the samples. This method enabled aggressive leukaemias to be selected. The radiosensitivity showed wide variations from one patient to another (Do ranging from 0.35 to 2.6 Gy) whichever culture method used. The progenitor cells capable of self-renewal were more radiosensitive (Mean Do 0.9[+-]0.4 Gy) than terminal dividing cells (Mean Do = 1.35[+-]0.5 Gy). In two cases, a shoulder was found in the initial part of the cell-survival curves of cells capable of self-renewal. The shape of the curves was better fitted by the linear quadratic model with very low values of [alpha]/[beta], suggesting a reduced antileukaemic effect in case of fractionation.

  15. Radiative transfer modelling in combusting systems using discrete ordinates method on three-dimensional unstructured grids; Modelisation des transferts radiatifs en combustion par methode aux ordonnees discretes sur des maillages non structures tridimensionnels

    Energy Technology Data Exchange (ETDEWEB)

    Joseph, D.

    2004-04-01

    The prediction of pollutant species such as soots and NO{sub x} emissions and lifetime of the walls in a combustion chamber is strongly dependant on heat transfer by radiation at high temperatures. This work deals with the development of a code based on the Discrete Ordinates Method (DOM) aiming at providing radiative source terms and wall fluxes with a good compromise between cpu time and accuracy. Radiative heat transfers are calculated using the unstructured grids defined by the Computational Fluid Dynamics (CFD) codes. The spectral properties of the combustion gases are taken into account by a statistical narrow bands correlated-k model (SNB-ck). Various types of angular quadrature are tested and three different spatial differencing schemes were integrated and compared. The validation tests show the limit at strong optical thicknesses of the finite volume approximation used the Discrete Ordinates Method. The first calculations performed on LES solutions are presented, it provides instantaneous radiative source terms and wall heat fluxes. Those results represent a first step towards radiation/combustion coupling. (author)

  16. Chemical treatment proceed of poor uranium content ores; Un procede de traitement chimique des minerais pauvres d'uranium

    Energy Technology Data Exchange (ETDEWEB)

    Mouret, P [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires; Pagny, P [Societe Potasse et Engrais Chimiques (France)

    1955-07-01

    The needs in uranium constantly increased inciting to develop new chemical processes for the treatment of uranium ores. we searched processes that permit to get this element from ores poor in uranium, to a reasonable cost price. We used a sulphuric attack and a precipitation of uranium as phosphate uranate or pyrophosphate uranate to separate its from the different impurities. The process permitted to process ores contents of about 0,05% of uranium and to get an end product of sodium carbonate uranate containing 60 to 65% of uranium, with an acceptable cost price and an extraction yield situated between 90 and 95%. (M.B.) [French] Les besoins sans cesse accrus en uranium ont incite de developper de nouveaux procedes chimiques pour le traitement de minerais uranifere. nous avons recherche des procedes qui permettent d'obtenir cet element a partir de minerais pauvres en uranium, a un prix de revient raisonnable. Nous nous sommes orientes vers une attaque sulfurique et une precipitation de l'uranium sous forme de phosphate uraneux ou de pyrophosphate uraneux pour le separer des differentes impuretes. Le procede a permis de descendre a des teneurs en uranium de l'ordre de 0,05 % et d'obtenir un produit final a l'etat d'uranate de soude contenant 60 e 65 % d'uranium, avec un prix de revient acceptable et avec un rendement global d'extraction situe entre 90 et 95 %. (M.B.)

  17. Comparison of the THYC and FLICA-3M codes by the pseudo-cubic thin-plate method; Comparaison par la methode des plaques de predicteurs de flux critique obtenus a l`aide des codes THYC et FLICA-3

    Energy Technology Data Exchange (ETDEWEB)

    Banner, D; Crecy, F de

    1993-06-01

    The pseudo cubic Spline method (PCSM) is a statistical tool developed by the CEA. It is designed to analyse experimental points and in particular thermalhydraulic data. Predictors of the occurrence of critical heat flux are obtained by using Spline functions. In this paper, predictors have been computed from the same CHF databases by using two different flow analyses to derive local thermal-hydraulic variables at the CHF location. In fact, CEA`s FLICA-3M represents rod bundles by interconnected subchannels whereas EDF`s THYC code uses a porous 3D approach. In a first step, the PCSM is briefly presented as well as the two codes studied here. Then, the comparison methodology is explained in order to prove that advanced analysis of thermalhydraulic codes can be achieved with the PCSM. (authors). 6 figs., 2 tabs., 5 refs.

  18. Release monitoring and environmental surveillance of Cea centers. Assessment and regulation and method 1999; Controle des rejets et surveillance de l'environnement des centres CEA. Bilan et reglementation et methode 1999

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-07-01

    The quality of the natural environment around the centers of the Commissariat a l Energie Atomique is an important point of its safety policy. The environmental protection is based on the control of risks coming from research and development activities of its installations. It aims to reduce as low as possible, the impact of its activities on man and his environment. This publication develops the sampling and measurement methods that are made on effluents and in environment, according to the radionuclides characteristics, that are present. It gives also the regulation that applied to the effluents monitoring. The results of radioactive effluents releases (liquid and gaseous) and the surveillance of environment around cea centers is given in the 'Bilan 1999' publication. An analysis of these results on the 1995-1999 period allows to follow their evolution. (N.C.)

  19. Complexation of biological ligands with lanthanides(III) for MRI: Structure, thermodynamic and methods; Complexation des cations lanthanides trivalents par des ligands d'origine biologique pour l'IRM: Structure, thermodynamique et methodes

    Energy Technology Data Exchange (ETDEWEB)

    Bonnet, C

    2006-07-15

    New cyclic ligands derived from sugars and amino-acids form a scaffold carrying a coordination sphere of oxygen atoms suitable to complex Ln(III) ions. In spite of their rather low molecular weights, the complexes display surprisingly high relaxivity values, especially at high field. The ACX and BCX ligands, which are acidic derivatives of modified and cyclo-dextrins, form mono and bimetallic complexes with Ln(III). The LnACX and LnBCX complexes show affinities towards Ln(III) similar to those of tri-acidic ligands. In the bimetallic Lu2ACX complex, the cations are deeply embedded in the cavity of the ligand, as shown by the X-ray structure. In aqueous solution, the number of water molecules coordinated to the cation in the LnACX complex depends on the nature and concentration of the alkali ions of the supporting electrolyte, as shown by luminescence and relaxometric measurements. There is only one water molecule coordinated in the LnBCX complex, which enables us to highlight an important second sphere contribution to relaxivity. The NMR study of the RAFT peptidic ligand shows the complexation of Ln(III), with an affinity similar to those of natural ligands derived from calmodulin. The relaxometric study also shows an important second sphere contribution to relaxivity. To better understand the intricate molecular factors affecting relaxivity, we developed new relaxometric methods based on probe solutes. These methods allow us to determine the charge of the complex, weak affinity constants, trans-metallation constants, and the electronic relaxation rate. (author)

  20. Complexation of biological ligands with lanthanides(III) for MRI: Structure, thermodynamic and methods; Complexation des cations lanthanides trivalents par des ligands d'origine biologique pour l'IRM: Structure, thermodynamique et methodes

    Energy Technology Data Exchange (ETDEWEB)

    Bonnet, C

    2006-07-15

    New cyclic ligands derived from sugars and amino-acids form a scaffold carrying a coordination sphere of oxygen atoms suitable to complex Ln(III) ions. In spite of their rather low molecular weights, the complexes display surprisingly high relaxivity values, especially at high field. The ACX and BCX ligands, which are acidic derivatives of modified and cyclo-dextrins, form mono and bimetallic complexes with Ln(III). The LnACX and LnBCX complexes show affinities towards Ln(III) similar to those of tri-acidic ligands. In the bimetallic Lu2ACX complex, the cations are deeply embedded in the cavity of the ligand, as shown by the X-ray structure. In aqueous solution, the number of water molecules coordinated to the cation in the LnACX complex depends on the nature and concentration of the alkali ions of the supporting electrolyte, as shown by luminescence and relaxometric measurements. There is only one water molecule coordinated in the LnBCX complex, which enables us to highlight an important second sphere contribution to relaxivity. The NMR study of the RAFT peptidic ligand shows the complexation of Ln(III), with an affinity similar to those of natural ligands derived from calmodulin. The relaxometric study also shows an important second sphere contribution to relaxivity. To better understand the intricate molecular factors affecting relaxivity, we developed new relaxometric methods based on probe solutes. These methods allow us to determine the charge of the complex, weak affinity constants, trans-metallation constants, and the electronic relaxation rate. (author)

  1. Simulation de Ia propagation de fissures dans les solides elastiques en modes mixtes par Ia methode des equations integrales duales

    OpenAIRE

    Kebir , Hocine; Roelandt , Jean Marc; Gaudin , Jocelyn

    2000-01-01

    International audience; The present paper is concerned with the effective numerical implementation of the two dimensional Dual Boundary element method to analyse the mixed-mode crack growth All the boundaries are discretized with discontinuous quadratic boundary elements and the crack-tip is modeled by singular elements that exactly represent the strain field singularity $1/\\sqrt{r}$. The Stress lntensity Factors can be computed very accurately from the crack opening dis placement at collocat...

  2. Resolution of crystal structures by X-ray and neutrons powder diffraction using global optimisation methods; Resolution des structures cristallines par diffraction des rayons X et neutrons sur poudres en utilisant les methodes d'optimisation globale

    Energy Technology Data Exchange (ETDEWEB)

    Palin, L

    2005-03-15

    We have shown in this work that X-ray diffraction on powder is a powerful tool to analyze crystal structure. The purpose of this thesis is the resolution of crystal structures by X-ray and neutrons diffraction on powder using global optimisation methods. We have studied 3 different topics. The first one is the order-disorder phenomena observed in some globular organic molecular solids. The second is the opiate family of neuropeptides. These neurotransmitters regulate sensory functions including pain and control of respiration in the central nervous system. The aim of our study was to try to determine the crystal structure of Leu-enkephalin and some of its sub-fragments. The determination of the crystal structures has been done performing Monte Carlo simulations. The third one is the location of benzene in a sodium-X zeolite. The zeolite framework was already known and the benzene has been localized by simulated annealing and by the use of maximum entropy maps.

  3. Role of LPG as an energy substitute in Algeria; Role des G.P.L. comme energie de substitution en Algerie

    Energy Technology Data Exchange (ETDEWEB)

    Boukadoum, Abdelhamid; Houghlaouene, Samir

    2010-09-15

    Algeria is a leader country in LPG industry. The availability of resources and the upstream production development efforts have oriented the large energy choices in terms of domestic market need satisfaction. LPG (propane and butane) plays a massive role in the change towards clean energy (case of LPG versus gas) and towards more practical energy (i.e. the case of bulk propane versus the packed butane, or versus natural gas). [French] L'Algerie est un pays leader dans l'industrie des GPL. La disponibilite des ressources et les efforts de developpement de la production en amont ont oriente les grands choix energetiques en matiere de satisfaction des besoins du marche domestique. En effet, les GPL (propane et butane) jouent un role majeur dans la substitution vers les sources d'energie propres (cas du GPL/C par rapport aux essences) et vers des energies plus commodes (par exemple le cas du propane vrac par rapport au butane conditionne, voire par rapport au gaz naturel).

  4. Multidimensional method for the determination of control power considering uncertainties; Multidimensionales Verfahren zur Bestimmung des Regelleistungsbedarfes unter Beruecksichtigung von Unsicherheiten

    Energy Technology Data Exchange (ETDEWEB)

    Kays, Jan; Schwippe, Johannes; Waniek, Daniel; Rehtanz, Christian [Technische Univ. Dortmund (Germany). Lehrstuhl fuer Energiesysteme und Energiewirtschaft

    2010-12-15

    One of the most crucial constraints in operation of electrical power supply systems is the permanent balance between generation and load. Reserve power is held ready to be able to keep this balance also in case of the occurrence of unpredictable events like power plant outages or inevitable deviations of power injections from their predicted values. At this, the allocation of operating reserves is in the field of conflict between level of reliability and cost effectiveness. The amount of reserve generation capacity required in a control area heavily depends on prediction quality which constitutes the need for high quality predictions. This article is about the influence of prediction quality on the amount of reserve generation capacity required in a control area. The algorithms for the assessment of required reserve generation capacity known from literature use the variation calculus technique to account for the aforementioned unpredictable events and prediction errors. In this article, an extension to a convolution-based method is presented in which the uncertainties of the predictions are expressed using intervals. Each parameter is represented by an independent dimension, assuming statistical independence among them. This allows the distinct analysis of each parameter's influence on the amount of required reserve generation capacity. In addition, two methods for the visualization of the multi-dimensional results are presented, allowing a comprehensive analysis of the parameters' influences. Standard distribution functions are used to represent the parameters for the simulation and the results are shown as probability density functions of possible imbalances. Based on forecasts of the development of conventional power plants and regenerative generation in the years 2020, 2030 and 2040, the required control power of the future German transmission system is calculated. Influences and dependencies are identified with the extended convolution-based method

  5. Continuous and discreet methods in the aggregation and des fuzzy stages of a diffuse controller of neutron power

    International Nuclear Information System (INIS)

    Najera H, M.C.; Benitez R, J.S.

    2003-01-01

    The results of a comparative study are presented of: to) A denominated diffuse controller 'exact', designed by means of an innovative method that determines analytically so much the group of exit resultant in the aggregation stage like the de fuzzy process, and b) a diffuse controller denominated 'discreet' based on the discretization of the variable of having left as much for the aggregation as for the de fuzzy. These stages incorporated to the control algorithms whose objective is the ascent and regulation of the neutron power, carrying out an analysis of its performance. (Author)

  6. Essai de classement typo-technologique des araires à partir des pièces métalliques découvertes en Gaule romaine en vue de leur reconstitution Setting up of a typological-technological classification method to try to reconstruct ards from metallic pieces found in Roman Gaul

    Directory of Open Access Journals (Sweden)

    André Marbach

    2008-04-01

    Full Text Available Les pièces métalliques d’instruments aratoires sont, pour la Gaule romaine, pratiquement les seuls éléments archéologiques à notre disposition nous permettant de reconstruire ces outils. Des auteurs tels que S.E. Rees (G.B., R. Pohanka (Autriche et surtout J. Henning (Europe du sud-est ont fait des propositions de reconstitution des instruments aratoires de cette époque. Que faut-il en penser ? Une méthode de recherche a été élaborée à partir d’une analyse fine des pièces métalliques d’un catalogue de ces pièces pour les Gaules. Les socs ont été classés en fonction de leur surface utile, de la forme de leur douille de fixation et de l’angle d’usure de la pièce avec le sol, quand il est observable. Pour les reilles, le classement est identique et la longueur de la soie est ici prise en compte. À partir des valeurs retenues pour ces pièces et d’une étude technique avec modélisation de l’instrument aratoire, les possibilités de reconstruction des araires ont été étudiées. On souhaite ainsi rappeler aux chercheurs combien il est important de publier les pièces retrouvées avec le maximum de précision, dans les dessins et les mesures. En conclusion, pour les araires à soc à douille, de nombreuses incertitudes demeurent, sauf pour les socs de petites surfaces utiles, qui sont généralement des araires manche-sep. Pour les araires à reille, la reconstruction des instruments semble accessible, y compris la longueur du timon de traction ou chambige. Quelques exemples concrets de reconstitution sont présentés, dont un araire tourne-oreille.Metallic pieces of tilling implements from Roman Gaul, are practically the only archaeological elements at our disposal to reconstruct the tools. Authors such as S.E. Rees (GB, R. Pohanka (Austria, and above all J. Henning (South East of Europe have made proposals concerning the reconstruction of tilling implements of that period. What is to be thought of these

  7. Study of some properties of 's' neutron resonance parameters for target nuclei I = 1/2 and I = 3/2 in function of spin value J = I + 1/2 in the energy range 1 {yields} 5000 eV; Etude de quelques proprietes des parametres de resonances des neutrons ''s'' pour des noyaux cibles I = 1/2 et I = 3/2 en fonction de la valeur du spin J = I + 1/2 dans le domaine d'energie 1 eV {yields} 5000 eV

    Energy Technology Data Exchange (ETDEWEB)

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

    1967-05-15

    Different kinds of experiments and analysis methods allowing to achieve neutron resonances parameters in the low energy range (1 eV {yields} 5000 eV) are described. A great deal of effort to improve experimental conditions and data processing in order to know the spin value J = I {+-} 1/2 has been spent. The time of flight method was used. A few target nuclei I = 3/2 and 1 = 1/2 have been studied. For I = 3/2 (Ga, As, 3r, Au) we find S{sub o} J = 2 {approx_equal} 2 S{sub o} J = 1 and S{sub o} J = 1 {approx_equal} S{sub o} J = 0 for I = 1/2 (Tm, Pt) but {sup 77}Se. Fluctuations of the total radiative width {gamma}{sub {gamma}} depend on the spin value I = I {+-} 1/2 when E1 transition, are enhanced for one of the both spin states. The magnitude of these fluctuations can be explained of the strength of E1 transitions (E{sub {gamma}} {approx} 7 MeV) is supposed to be proportional to E{sup 5}{sub {gamma}} instead of E{sup 3}{sub {gamma}}. The distribution of levels spacings against spin value J are considered and are compared to theoretical predictions. (author) [French] On decrit les differentes methodes d'analyse permettant d'obtenir les parametres des resonances de neutron dans le domaine d'energie 1 eV {yields} 5000 eV. Un effort particulier a ete fait pour connaitre la valeur du spin J = I {+-} 1/2. Les types d'experience et les analyses des donnees, developpes et ameliores pour determiner J sont decrits. Les resultats obtenus ont permis l'etude de differentes proprietes en fonction du spin J. On trouve: S{sub o} J 2 {approx_equal} 2 S{sub o} J = 1 pour les noyaux I = 3/2 etudies (Ga, As, Br, Au) et S{sub o} J = 1 {approx_equal} S{sub o} J = 0 Pour le Tm et {sup 195}Pt de spin I = 1/2. On constate que les largeurs radiatives totales {gamma}{sub {gamma}} fluctuent si des transitions E1 aux premiers etats excites sont favorisees. Ces fluctuations peuvent etre expliquees si on suppose que les intensites de ces transitions sont proportionnelles a E{sup 5}{sub {gamma

  8. A new detector for the measurement of neutron flux in nuclear reactors; Nouvelle methode de mesure des flux de neutrons dans les reacteurs atomiques

    Energy Technology Data Exchange (ETDEWEB)

    Koch, L; Labeyrie, J; Tarassenko, S [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1958-07-01

    The detector described is designed for the instantaneous measurement of thermal neutron fluxes, in the presence of high {gamma} ray activity; this detector can withstand temperatures as high as 500 deg. C. It is based on the following principle: radioactive atoms resulting from heavy-nucleus fission are carried by a gas flow to a detector recording their {beta} and {gamma} disintegration. Thermal neutron fluxes as low as few neutrons per cm{sup 2} per second can be measured. This detector may be used to control a nuclear reactor, to plot the thermal flux distribution with an excellent definition (1 mm{sup 2}) for fluxes higher than 10{sup 8} n/cm{sup 2}/s. The time response of the system to a sharp variation of flux is limited, in case of large fluxes, to the transit time of the gas flow between the fission product emitter and the detector; of the order of one tenth of a sec per meter of piping. The detector may also be applied for spectroscopy of fission products eider than 0,1 s. (author)Fren. [French] On decrit un appareil permettant la mesure instantanee des flux de neutrons thermiques accompagnes de flux intenses de rayons {gamma} et situes dans des enceintes pouvant etre portees a des temperatures superieures a 500 deg. C. On utilise la radioactivite des atomes resultant de la fission des noyaux lourds; ces atomes sont entraines par un courant gazeux vers un detecteur de radioactivite qui enregistre leurs desintegrations {beta} et {gamma}. On peut mesurer des flux partir de quelques neutrons thermiques par cm{sup 2} et par seconde. L'appareil permet de suivre la puissance d'un reacteur atomique, de tracer des cartes de densite de neutrons avec une tres bonne definition (1 mm{sup 2}) dans le cas de flux superieurs a 10{sup 8} cm{sup 2}/s. Le temps de reponse du systeme a une variation du flux de neutrons est limite, poes flux importants, par le temps de transit du gaz entre l'emetteur de produits de fission et le detecteur: soit quelques dizaines de

  9. Acoustical monitoring of diesel engines in reverberant environment; Methodes de surveillance acoustique des diesels en milieu reverberant

    Energy Technology Data Exchange (ETDEWEB)

    Mein, M.

    1995-10-01

    The feed-back knowledge of emergency diesel generators in nuclear power plants shows that some malfunctions, mainly affecting fuel-injection or distribution system of the engine can be heard and detected by experienced maintenance agents. This study consists in the feasibility,v of acoustical monitoring of those diesel engines, taking into account the reverberant environment of the machine. The operating cycle of the diesel is composed of transient events (injection, combustion, valve closure...) which generate highly non stationary acoustical signals. The detection of a malfunction appearing on such transients requires the use of adapted signal processing techniques. Visual analysis of the phenomena is first proceeded using time-frequency and time-scale representations. The second step will be parametric modeling of acoustical signatures for the extraction of characteristic parameters, in order to characterize the fault and to use an automatic classification system. The lest part of the study will concern the evaluation of the robustness of the detection methods in regard to acoustical reverberation. (author). 10 refs., 6 figs.

  10. The controlled of the materials by the method of oscillation at the reactor core of Chatillon; Le controle des materiaux par la methode d'oscillation a la pile de Chatillon

    Energy Technology Data Exchange (ETDEWEB)

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

    1955-07-01

    Nuclear controls has for aim to determine the validity of materials intended to be used for the construction of the reactor core. The cross-section of capture of these materials has to be measured while comparing them either to a standard of the same material, either to an element of cross-section supposed known. We studied the disruption of the working of the reactor generated by the periodic introduction of a sample of the studied material. This method is based on the measure of the phase angle of the signal provided by the ionization chamber. This signal results from the composition of a local signal and an aggregate signal due to the effects of diffusion and capture. This method permits the comparison of the capture of 2 samples very dispersive and few capturing as the graphite, the beryllium, the beryllium oxide, with a good precision. It permits to determine the cross-section of capture of elements as magnesium or aluminum. (M.B.) [French] Le controle nucleaire a pour but de determiner la valeur des materiaux destines a etre utilises pour la construction des piles. II s'agit de mesurer la section efficace de capture de ces materiaux en les comparant soit a un echantillon etalon du meme materiau, soit a un element de section efficace supposee connue. On etudie la perturbation du fonctionnement de la pile engendree par l'introduction periodique d'un echantillon du materiau a etudier. Cette methode est basee sur la mesure de l'angle de phase du signal fourni par la chambre d'ionisation. Ce signal resulte de la composition d'un signal local et d'un signal global dus aux effets de diffusion et de capture. Cette methode permet la comparaison de la capture de 2 echantillons de corps tres diffusants et peu capturants comme le graphite,le beryllium, l'oxyde de beryllium, avec une bonne precision. Elle permet par ailleurs de determiner la section efficace de capture de corps tels que le magnesium ou l'aluminium. (M.B.)

  11. Contribution of the ultrasonic simulation to the testing methods qualification process; Contribution de la modelisation ultrasonore au processus de qualification des methodes de controle

    Energy Technology Data Exchange (ETDEWEB)

    Le Ber, L.; Calmon, P. [CEA/Saclay, STA, 91 - Gif-sur-Yvette (France); Abittan, E. [Electricite de France (EDF-GDL), 93 - Saint-Denis (France)

    2001-07-01

    The CEA and EDF have started a study concerning the simulation interest in the qualification of nuclear components control by ultrasonic methods. In this framework, the simulation tools of the CEA, as CIVA, have been tested on real control. The method and the results obtained on some examples are presented. (A.L.B.)

  12. Rapid method of identification of {beta}-ray emitters and of {beta}-radioactive impurity dosage (1961); Methode rapide d'identification des emetteurs-{beta} et de dosage d'impuretes radioactives-{beta} (1961)

    Energy Technology Data Exchange (ETDEWEB)

    Le Gallic, Y; Legrand, J; Grinberg, B [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1961-07-01

    We describe a simple method of radioactive analysis, which allows an accurate determination of maximal energies of {beta}-emitters, and detection and titration of radioactive impurities in radionuclides as well. The method described, which uses a plastic scintillator, is based on the fact that the curve obtained by plotting the number of pulses measured against the threshold is a straight line, in the case of pure {beta}-emitters. We then derive a simple relation between the data of this straight line and the maximal energy of the {beta}-spectrum of the radionuclide under consideration. (authors) [French] Description d'une methode simple d'analyse radioactive, permettant de determiner avec precision l'energie maximum des emetteurs-{beta}, ainsi que de deceler et de doser les impuretes radioactives dans un radionuclide. La technique decrite utilise un scintillateur plastique. On exploite le fait que la courbe du nombre d'impulsions mesurees, en fonction du seuil de discrimination, est une droite, pour un emetteur-{beta} pur. Une relation simple entre les caracteristiques de cette droite et l'energie maximum du spectre-{beta} du radionuclide, correspondant, a ete etablie. (auteurs)

  13. Investigation of the diffusion {proportional_to} brasses using methods depending on the evaporation or condensation of zinc; Etude de la diffusion dans les laitons {proportional_to} au moyen des methodes d'evaporation ou de condensation du zinc

    Energy Technology Data Exchange (ETDEWEB)

    Accary, A [Commissariat a l' Energie Atomique, Saclay (France).Centre d' Etudes Nucleaires; Centre d' Etudes de Chimie Metallurgique du CNRS (France)

    1959-07-01

    Diffusion in {alpha} brasses has been investigated using methods involving the evaporation and the condensation of zinc. Having shown that at sufficiently high temperatures intergranular diffusion has no effect, it was then proved that the rate of evaporation or of condensation can only be defined if the mechanical treatment of the test piece before diffusion, the direction of the diffusion and the nature of the impurities present are also defined. The coefficient of diffusion D is then given by the equation D ({pi}/4t){rho}{sup 2}{sub 0} where t is the duration of the diffusion; {rho}{sub 0} is the extrapolated value of {rho} = ({delta}m)/({delta}C) for a zero value of the variation of concentration ({delta}m in is the change in weight of the test piece per unit surface; {delta}C is the difference between the concentration at the surface and the initial concentration of the test piece). This method has been used to study the effect of the direction of the diffusion on the coefficient of diffusion. The coefficient for diffusion which decreases the concentration of zinc is 5 times greater than that for diffusion which increases the quantity of zinc in the metal; an interpretation of this phenomena based on the mechanism of diffusion vacancies in the structure has been proposed. By means of micrographic investigation and by weighing it has been shown that the presence of certain impurities, such as phosphorous, arsenic, antimony, silicon, and aluminium can result in a marked increase of the rate of diffusion: the effect of these impurities on the coefficient of diffusion has been related to their valency and atomic weight. (author) [French] La diffusion dans les laitons {alpha} a ete etudiee au moyen des methodes d'evaporation et de condensafion du zinc. Apres avoir montre qu'aux temperatures suffisamment elevees, la diffusion intergranulaire ne jouait aucun role, l'auteur a prouve que la vitesse d'evaporation ou de condensation n'est definie que dans la mesure ou

  14. Diffusion Parameters of BeO by the Pulsed Neutron Method; Calcul des Parametres de Diffusion de BeO par la Methode des Neutrons Pulses; Opredelenie diffuzionnykh parametrov BeO s pomoshch'yu metoda impul'snykh nejtronov; Determinacion de los Parametros de Difusion en el BeO por el Metodo de los Neutrones Pulsados

    Energy Technology Data Exchange (ETDEWEB)

    Joshi, B. V.; Nargundkar, V. R.; Subbarao, K. [Atomic Energy Establishment Trombay, Bombay (India)

    1965-08-15

    The use of the pulsed neutron method for the precise determination of the diffusion parameters of moderators is described. The diffusion parameters of BeO have been obtained by this method. The neutron bursts were produced from a cascade accelerator by pulsing the ion source and using the Be (d, n) reaction. The detector was an enriched boron trifluoride proportional counter. It is shown that by a proper choice of the counter position arid length, and the source position, most of the space harmonics can be eliminated. Any constant background can be accounted for in the calculation of the decay constant. Very large bucklings were not used to avoid time harmonics. Any remaining harmonic content was rendered ineffective by the use of adequate time delay. The decay constant of the fundamental mode of the thermal neutron population was determined for several bucklings. Conditions to be satisfied for an accurate determination of the diffusion cooling constant C are discussed. The following values are obtained for BeO: {lambda}{sub 0} = absorption constant = 156.02 {+-} 4.37 s{sup -1} D = diffusion coefficient = (1.3334 {+-} 0.0128) x 10{sup 5} cm{sup 2}/s C = diffusion cooling constant = (-4.8758 {+-} 0.5846) x 10{sup 5} cm{sup 4}/s. The effect of neglecting the contribution of the B{sup 6} term on the determination of the diffusion parameters was estimated and is shown to be considerable. The reason for the longstanding discrepancy between the values of C obtained for the same moderator by different workers is attributed to this. (author) [French] Les auteurs decrivent l'emploi de la methode des neutrons puises pour la determination precise des parametres de diffusion des ralentisseurs. Ils ont calculi ceux de la glucine par cette methode. Des deuterons puises au moyen d'un accelerateur a cascade produisaient les bouffees de neutrons par la reaction Be (d, n). Le detecteur etait constitue par un compteur proportionnel au BF{sub 3} enrichi. En choisissant convenablement

  15. A Comparison of Radioisotope Methods for River Flow Measurement; Comparaison de methodes radioisotopiques de mesure du debit des cours d'eau; Sravnenie radioizotopnykh metodov izmereniya rechnykh stokov; Comparacion de los metodos radioisotopicos para medir el caudal de los rios

    Energy Technology Data Exchange (ETDEWEB)

    Clayton, C. G.; Smith, D. B. [Wantage Research Laboratory Atomic Energy Research Establishment Wantage, Berks (United Kingdom)

    1963-08-15

    which affect the general application of tracer techniques to river flow measurement will be presented. It is concluded that all three methods can be satisfactorily used. The Continuous Sample Method is ultimately preferred as it gives the highest accuracy for the smallest quantity of tracer. [French] Aux fins d'une etude comparative des methodes radioisotopiques de mesure de debit fluvial, on a employe les methodes de dilution, d'echantillonnage continu et de comptage total sur l'Aylburton (Gloucestershire), l'Usway et l'Alwin (Northumberland). Ces trois cours d'eau presentent des particularites geologiques differentes et leur debit varie entre 2,5 1 et 3 m{sup 3}/s. Dans toutes les methodes de mesure de debit faisant appel a l'emploi d'indicateurs, il est souhaitable que la distance entre le point ou la mesure est effectuee et celui ou l'indicateur est introduit soit suffisamment grande pour permettre un brassage lateral complet. D'autre part, cette distance doit etre suffisamment reduite pour que la dispersion longitudinale ne soir pas excessive ou que l'indicateur ne se perde pas par adsorption sur le lit. Le mecanisme de dispersion est lie aux caracteristiques hydrologiques du cours d'eau et a la methode utilisee. L'adsorption est fonction du choix de l'indicateur et de la nature geologique du lit de la riviere. Le tritium est ideal a cet egard car il n'est pas adsorbe, mais il est difficile a mesurer et on ne peut pas suivre directement son mouvement dans la riviere. D'autres indicateurs conviennent mieux, mais ils peuvent etre adsorbes. On a etudie le degre d'adsorption de {sup 24}Na, {sup 82}Br et {sup 32}P sous forme de NaHCO{sub 3}, NH{sub 4}Br et NaH{sub 2}P0{sub 4}, en comparant les mesures faites en plusieurs points situes en aval d'un point unique d'injection et en introduisant de l'eau tritiee (HTO) en meme temps que chacun des trois indicateurs. Il s'est revele que {sup 32}P est sujet a une forte chimiosorption, comme on le supposait, et n'est par

  16. Fabrication Methods of Fullerenes. a Critical Review Méthodes de fabrication des fullerènes. Une étude critique

    Directory of Open Access Journals (Sweden)

    Emberson S. C.

    2006-11-01

    Full Text Available The industrial use of fullerenes will require a significant up-scaling of their production. The five actually known techniques are discussed : 1. The electric arc (Krätschmer-Huffman. 2. The vaporization of carbon by pulsed lasers. 3. The direct vaporization of carbon in focused sunlight. 4. The direct inductive heating of carbon. 5. Sooting hydrocarbon flames. The difficulty of up-scaling the electric arc set-up because of the photochemical destruction of fullerenes will be demonstrated. The use of sooting hydrocarbon flames for an industrial production of fullerenes is suggested. L'utilisation industrielle de fullerènes nécessitera une augmentation significative de leur production. Les cinq techniques actuellement connues sont discutées : 1. L'arc électrique (Krätschmer-Huffman. 2. L'évaporation de carbone par laser pulsé. 3. L'évaporation de carbone par lumière solaire focalisée. 4. L'évaporation thermique de carbone. 5. Une flamme d'hydrocarbures formant des suies. On met en évidence la difficulté d'une montée en échelle des installations à base d'arcs électriques à cause de la destruction photochimique des fullerènes. L'utilisation de flammes produisant des suies est proposée pour la production industrielle de fullerènes.

  17. Des Connaissances Aux Politiques

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

    Les synergies ont été mises en commun au fur et à mesure des progrès de la recherche. .... Recherche normative (sur le rôle et la performance des institutions .... Système national d'information sur la gestion environnementale connecté à 19 ...... Un fort contrôle centralisé sur l'élaboration des politiques nationales peut ...

  18. Nouvelles méthodes d'identification des fractures par diagraphie acoustique en full wave form New Methods of Identifying Fractures by Full Wave Form Acoustic Logging

    Directory of Open Access Journals (Sweden)

    Denis A.

    2006-11-01

    Full Text Available Les outils acoustiques de dernière génération permettent maintenant d'enregistrer l'ensemble des ondes générées par une source acoustique à l'intérieur d'une géométrie cylindrique telle qu'un puits de sondage. Le train d'onde qu'il est alors possible d'analyser se compose successivement de trois composantes majeures (l'onde de compression, de cisaillement et de Stoneley dont nous avons une représentation pour chaque position de la sonde à l'intérieur du puits. Nous présentons, dans ce texte, trois méthodes originales et rapides (calculs possibles sur le site même pour identifier, à partir du traitement de l'onde de Stoneley, les fractures ouvertes recoupées par un forage. Nous donnons, dans un premier temps, nos motivations pour le choix unique du traitement de l'onde de Stoneley pour, dans un deuxième temps, exposer les trois méthodes développées et montrer pour chacune d'entre elles une application pratique. Interest in recognizing and identifying fractures in a coherent formation for the petroleum, geothermal and storage (oil and gas, wastes sectors has led to the development of indirect prospection methods inside boreholes such as acoustic logging. The latest acoustic tools are capable of recording all waves generated by an acoustic logging tool inside a cyclindrical geometry such as a borehole. The wavetrain that can then be analyzed is successively made up of three major components (the P compression wave, the S shear wave and the Stoneley wave for which we have a representation for each position of the logging tool in the borehole. An example of a recording is shown in Fig. 1. Because of its specific features (high amplitudes, low frequency, high signal-to-noise ratio, the Stoneley wave is recognized to be a good indicator of open fractures. Therefore, we use simple digital processing to quantify the influence of fracturing on the propagation of the Stoneley wave. Three methods stemming from the digital processing of

  19. Further development of microparticle image velocimetry analysis for characterisation of gas streams as a novel method of fuel cell development. Final report; Weiterentwicklung des Mikro-Particle Image Velocimetry Analyseverfahrens zur Charakterisierung von Gasstroemungen als neuartige Entwicklungsmethodik fuer Brennstoffzellen. Schlussbericht

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2012-07-01

    The project aimed at a better understanding of the complex fluid-mechanical processes in the small ducts of bipolar plates. So far, an appropriate technology for in-situ measurement was lacking. The project therefore focused on the further development of microparticle image velocimetry in order to enable analyses of the local velocity distribution of a gas stream in a microduct. Further, measurements were carried out in the microducts of a fuel cell in the more difficult conditions of actual operation. (orig./AKB) [German] Anlass des Forschungsvorhabens war die komplizierten stroemungsmechanischen Zusammenhaenge in den kleinen Kanaelen der Bipolarplatten zu verstehen. Bisher stand keine Messtechnik zur Verfuegung, dies es erlaubt, die stroemungsmechanischen Prozesse in den Mikrokanaelen unter Realbedingungen in situ zu vermessen und mit der instantanen Zellleistung zu korrelieren, Ziel des Projektes war es daher, die Methode der Mikro-Partikel-Image-Velocimetry in der Art weiterzuentwickeln, dass eine Analyse der lokalen Geschwindigkeitsverteilung einer Gasstroemung in einem Mikrokanal ermoeglicht wird. Darueber hinaus wird als zweites Ziel des Projekts eine solche Messung unter den erschwerten Bedingungen einer betriebenen Brennstoffzelle in Mikrokanaelen einer Zelle durchgefuehrt.

  20. Prédiction des propriétés volumétriques des hydrocarbures par une translation de volume améliorée Prediction of the Volumetric Properties of Hydrocarbons with an Improved Volume Translation Method

    Directory of Open Access Journals (Sweden)

    Ungerer P.

    2006-12-01

    Full Text Available Ce résumé contient des formules (*** qui ne peuvent s'afficher à l'écran. À la suite des travaux de Péneloux et al. (1982 , plusieurs auteurs (Soreide, 1989; Magoulas et Tassios, 1990; Coniglio, 1993 ont proposé des méthodes de translation de volume pour mieux calculer les masses volumiques des liquides au moyen des équations d'état. Le présent travail vise à améliorer ces prédictions, en particulier dans les conditions des gisements pétroliers (températures jusqu'à 200°C et pressions atteignant 120 MPa, en utilisant l'équation d'état de Peng-Robinson. Comme les méthodes existantes sont parfois incohérentes dans ces conditions (ex. coefficient d'expansion thermique négatif nous avons dû mettre au point une expression originale pour la translation de volume. Dans ce but, nous avons utilisé des mesures de masse volumique à haute pression, et non les masses volumiques du liquide à saturation. On a ainsi étudié des hydrocarbures de plusieurs familles : n-alcanes de C6 à C40 cyclohexane, monoaromatiques de C6 à C12. La translation de volume c obéit approximativement à une dépendance linéaire en température et en masse moléculaire : c(T = (0,023 - 0,00056 MWT + (-34,5 + 0,4666 MW où c est exprimé en cm³/Mol, T en K et MW en g/mol. Avec cette expression, les écarts résiduels moyens à haute pression sont faibles (inférieurs à 3 % pour les hydrocarbures C6 à C13 étudiés. Pour les hydrocarbures plus lourds, les prévisions sont sensibles au choix des paramètres critiques et l'on recommande l'expression: (*** où v(Tref, Pref désigne le volume molaire liquide calculé par l'équation d'état non translatée dans les conditions où la mesure de masse volumique (Pref est disponible. À l'exception de la région péri-critique, la précision reste bonne à basse pression. La nouvelle méthode de translation de volume permet de supprimer les incohérences des méthodes existantes et, à l'opposé de celles

  1. Effets des electrons secondaires sur l'ADN

    Science.gov (United States)

    Boudaiffa, Badia

    Les interactions des electrons de basse energie (EBE) representent un element important en sciences des radiations, particulierement, les sequences se produisant immediatement apres l'interaction de la radiation ionisante avec le milieu biologique. Il est bien connu que lorsque ces radiations deposent leur energie dans la cellule, elles produisent un grand nombre d'electrons secondaires (4 x 104/MeV), qui sont crees le long de la trace avec des energies cinetiques initiales bien inferieures a 20 eV. Cependant, il n'y a jamais eu de mesures directes demontrant l'interaction de ces electrons de tres basse energie avec l'ADN, du principalement aux difficultes experimentales imposees par la complexite du milieu biologique. Dans notre laboratoire, les dernieres annees ont ete consacrees a l'etude des phenomenes fondamentaux induits par impact des EBE sur differentes molecules simples (e.g., N2, CO, O2, H2O, NO, C2H 4, C6H6, C2H12) et quelques molecules complexes dans leur phase solide. D'autres travaux effectues recemment sur des bases de l'ADN et des oligonucleotides ont montre que les EBE produisent des bris moleculaires sur les biomolecules. Ces travaux nous ont permis d'elaborer des techniques pour mettre en evidence et comprendre les interactions fondamentales des EBE avec des molecules d'interet biologique, afin d'atteindre notre objectif majeur d'etudier l'effet direct de ces particules sur la molecule d'ADN. Les techniques de sciences des surfaces developpees et utilisees dans les etudes precitees peuvent etre etendues et combinees avec des methodes classiques de biologie pour etudier les dommages de l'ADN induits par l'impact des EBE. Nos experiences ont montre l'efficacite des electrons de 3--20 eV a induire des coupures simple et double brins dans l'ADN. Pour des energies inferieures a 15 eV, ces coupures sont induites par la localisation temporaire d'un electron sur une unite moleculaire de l'ADN, ce qui engendre la formation d'un ion negatif transitoire

  2. Structure of simple liquids; Structure des liquides simples

    Energy Technology Data Exchange (ETDEWEB)

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

    1969-07-01

    The results obtained by application to argon and sodium of the two important methods of studying the structure of liquids: scattering of X-rays and neutrons, are presented on one hand. On the other hand the principal models employed for reconstituting the structure of simple liquids are exposed: mathematical models, lattice models and their derived models, experimental models. (author) [French] On presente d'une part les resultats obtenus par application a l'argon et au sodium des deux principales methodes d'etude de la structure des liquides: la diffusion des rayons X et la diffusion des neutrons; d'autre part, les principaux modeles employes pour reconstituer la structure des liquides simples sont exposes: modeles mathematiques, modeles des reseaux et modeles derives, modeles experimentaux. (auteur)

  3. Évaluation des pratiques agricoles des légumes feuilles : le cas des ...

    African Journals Online (AJOL)

    SARAH

    30 sept. 2017 ... ... de Biochimie et Immunologie Appliquée, Centre de Recherche en Sciences Biologiques, Alimentaires et .... l'intoxication des agriculteurs et des consommateurs, ... source d'alimentation en eau et au pouvoir d'achat des.

  4. Conventional method for the calculation of the global energy cost of buildings; Methode conventionnelle de calcul du cout global energetique des batiments

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2002-05-01

    A working group driven by Electricite de France (EdF), Chauffage Fioul and Gaz de France (GdF) companies has been built with the sustain of several building engineering companies in order to clarify the use of the method of calculation of the global energy cost of buildings. This global cost is an economical decision help criterion among others. This press kit presents, first, the content of the method (input data, calculation of annual expenses, calculation of the global energy cost, display of results and limitations of the method). Then it fully describes the method and its appendixes necessary for its implementation: economical and financial context, general data of the project in progress, environmental data, occupation and comfort level, variants, investment cost of energy systems, investment cost for the structure linked with the energy system, investment cost for other invariant elements of the structure, calculation of consumptions (space heating, hot water, ventilation), maintenance costs (energy systems, structure), operation and exploitation costs, tariffs and consumption costs and taxes, actualized global cost, annualized global cost, comparison between variants. The method is applied to a council building of 23 flats taken as an example. (J.S.)

  5. The uranium bearing shale ore-body at St-Hippolyte (Haut-Rhin). An example of research with statistical methods; Le gisement des schistes uraniferes de St-Hippolyte (Haut-Rhin). Exemple d'etude par calculs statistiques

    Energy Technology Data Exchange (ETDEWEB)

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

    1958-07-01

    The uranium bearing shale ore-body at St-Hippolyte was mainly proved by drillings, the results of which were studied through statistical methods. The author gives an account of his conclusions regarding the distribution of mineralization, its origin and, the estimate of reserves. The uranium mineralization is irregularly distributed in shales. On a vertical line, levels could be singled out: they are similar, as far as lithology is concerned, but each of them is characterized by a grade-population, according to a lognormal distribution. Horizontally, a connection is noted between grades and the overlying barren sandstone bed. These considerations, as well as a statistical study of U/Ra ratio, induced the author to consider that the mineralization of the richest level has an hydrothermal origin. It is only through an uranium diffusion from that level that the others are mineralized. The uranium which is contained in poorest beds has a syn-genetic origin. Furthermore, statistical methods bring us to an evaluation of reserves. In such a case, the evaluation is equivalent to the ore obtained by common arithmetical methods. Moreover, we are able to state precisely the upper and lower limits where a true tonnage or a true grade could be given with a definite value of statistical certainty. Then the author has been able to study the separation of reserves in grade-groups and to foresee the effect of sorting in connection with the lower possible grade and with extraction units (wagons, lorries, etc...), on which the sorting will be done. To conclude, the author indicates the value of both classical and statistical methods. These two techniques are completing each other and they solve different problems. (author) [French] Le gisement des schistes uraniferes de St-Hippolyte a ete reconnu essentiellement par sondages, dont les resultats ont ete etudies par les methodes du calcul statistique. L'auteur expose les conclusions auxquelles il a ete amene et qui concernent: la

  6. Identification and estimation ot carbohydrates using radioisotopic methods; Identification et dosage des hydrates de carbone a l'aide des radioisotopes; Identifikatsiya i opredelenie karbogidratov s pomoshch'yu radioizotopnykh metodov; Identificacion u valoracion de hidratos de carbono con ayuda de radioisotopos

    Energy Technology Data Exchange (ETDEWEB)

    Phillips, G O; Criddle, W J [Department of Chemistry, University College, Cardiff (United Kingdom)

    1962-01-15

    Isotope-dilution methods have been developed to identify and estimate the small amount of products formed when carbohydrates are irradiated in aqueous solution with Co{sup 60} gamma-radiation. Conventional analytical methods proved inadequate. After irradiation of C{sup 14}-sugar solutions, the autoradiographs prepared after paper chromatography indicated extensive degradation. Using a reverse isotope-dilution procedure involving the addition of known carriers, and conversion of the fragments into crystalline derivatives, various constituents were quantitatively determined. It is possible to distinguish between d- and Z-isomers, and estimate each isomer independently. The method is applicable to other analytical problems in carbohydrate chemistry. A new method for scanning and recording the radioactivity along paper-chromatogram strips, which involves an inexpensive modification to conventional counting equipment, is described. (author) [French] On a mis au point des methodes de dilution isotopique destinees a identifier et a doser les menues quantites de produits qui se forment lorsque des hydrates de carbone en solution aqueuse sont irradies par les rayons gamma du cobalt-60. A cet egard, les methodes d'analyse classiques se sont revelees inadequates. Apres irradiation de solutions de sucre marque au carbone-14, les autoradiogrammes etablis a la suite d'une chromatographic sur papier indiquaient une forte degradation. En recourant a une methode de dilution isotopique inverse, avec adjonction d'entraineurs connus, et en operant une conversion des fragments en derives cristallins, on a pu determiner quantitativement plusieurs elements constitutifs. Il est possible de distinguer les isomeres dextrogyres des isomeres levogyres et de doser chaque isomere independamment. La methode peut etre appliquee a d'autres problemes d'analyse dans la chimie des hydrates de carbone. Le memoire decrit une nouvelle methode permettant d'explorer et d'enregistrer la radioactivite de

  7. Probabilistic methods for the simulation of fuel particles behavior under irradiation; Apport des methodes probabilistes dans la simulation du comportement sous irradiation du combustible a particules

    Energy Technology Data Exchange (ETDEWEB)

    Cannamela, C

    2007-09-15

    This work is devoted to the evaluation of mathematical expectations in the context of structural reliability. We seek a failure probability estimate (that we assume low), taking into account the uncertainty of influential parameters of the System. Our goal is to reach a good compromise between the accuracy of the estimate and the associated computational cost. This approach is used to estimate the failure probability of fuel particles from a HTR-type nuclear reactor. This estimate is obtain by means of costly numerical simulations. We consider different probabilistic methods to tackle the problem. First, we consider a variance reducing Monte Carlo method: importance sampling. For the parametric case, we propose adaptive algorithms in order to build a series of probability densities that will eventually converge to optimal importance density. We then present several estimates of the mathematical expectation based on this series of densities. Next, we consider a multi-level method using Monte Carlo Markov Chain algorithm. Finally, we turn our attention to the related problem of quantile estimation (non extreme) of physical output from a large-scale numerical code. We propose a controlled stratification method. The random input parameters are sampled in specific regions obtained from surrogate of the response. The estimation of the quantile is then computed from this sample. (author)

  8. Methods of Particle Detection in Free Neutron Decay; Methode de detection des particules dans une desintegration de neutrons libres; Metod obnaruzheniya chastits pri raspade svobodnogo nejtrona; Metodo para la deteccion de particulas en la desintegracion de neutrones libres

    Energy Technology Data Exchange (ETDEWEB)

    Novey, T B [Argonne National Laboratory, Lemont, IL (United States)

    1960-06-15

    A number of experimental studies have recently been completed by the Argonne Group on the decay of polarized neutrons in order to elucidate the structure of the weak nuclear interaction. These studies have taken the form of the measurement of the. angular distributions of electrons and protons with respect to the spin direction of the decaying free neutrons. The basic components of the apparatus which will be discussed are: 1. The one-meter iron-cobalt mirror which selects a beam of highly polarized neutrons and the methods for determination of the polarization. 2. The electron detector comprising a 10 cm diameter, 6 mm thick mosaic of anthracene crystals, and its light pipe system. 3. The proton detector, a 14-stage electron multiplier system, the first stage with a 15x15 cm opening, tapering in four stages to a standard 10-stage multiplier structure, and its entrance baffles for angular resolution. 4. The electronic system which selects pulses from the detectors having the proper time sequence, relative time-delay and pulse-height to allow indentification of a neutron decay. (author) [French] Le groupe Argonne a termine recemment des etudes experimentales sur la desintegration des neutrons polarises, en vue de mettre en lumiere le processus de l'interaction nucleaire faible. Ces etudes consistaient a mesurer les distributions angulaires d'electrons et de protons par rapport a la direction du spin des neutrons libres en voie de desintegration. Les principaux elements de l'appareillage qui sera decrit sont: 1. Le miroir de ferro-cobalt d'un metre, qui isole un faisceau de neutrons hautement polarises, ainsi que les methodes permettant de determiner la polarisation. 2. Le detecteur electronique qui comprend une mosaique de 10 cm de diametre et de 6 mm d'epaisseur en cristaux d'anthracene, et son systeme selectif. 3. Le detecteur de protons, un systeme multiplicateur electronique a 14 etages, le premier ayant une ouverture de 15x15 cm se retrecissant en 4 etages pour

  9. Non-analogue Monte Carlo method, application to neutron simulation; Methode de Monte Carlo non analogue, application a la simulation des neutrons

    Energy Technology Data Exchange (ETDEWEB)

    Morillon, B.

    1996-12-31

    With most of the traditional and contemporary techniques, it is still impossible to solve the transport equation if one takes into account a fully detailed geometry and if one studies precisely the interactions between particles and matters. Only the Monte Carlo method offers such a possibility. However with significant attenuation, the natural simulation remains inefficient: it becomes necessary to use biasing techniques where the solution of the adjoint transport equation is essential. The Monte Carlo code Tripoli has been using such techniques successfully for a long time with different approximate adjoint solutions: these methods require from the user to find out some parameters. If this parameters are not optimal or nearly optimal, the biases simulations may bring about small figures of merit. This paper presents a description of the most important biasing techniques of the Monte Carlo code Tripoli ; then we show how to calculate the importance function for general geometry with multigroup cases. We present a completely automatic biasing technique where the parameters of the biased simulation are deduced from the solution of the adjoint transport equation calculated by collision probabilities. In this study we shall estimate the importance function through collision probabilities method and we shall evaluate its possibilities thanks to a Monte Carlo calculation. We compare different biased simulations with the importance function calculated by collision probabilities for one-group and multigroup problems. We have run simulations with new biasing method for one-group transport problems with isotropic shocks and for multigroup problems with anisotropic shocks. The results show that for the one-group and homogeneous geometry transport problems the method is quite optimal without splitting and russian roulette technique but for the multigroup and heterogeneous X-Y geometry ones the figures of merit are higher if we add splitting and russian roulette technique.

  10. Study of the effect of positive ions impinging sensitive emulsions in mass spectrography; Etude de l'action des ions positifs sur les emulsions sensibles en spectrographie de masse

    Energy Technology Data Exchange (ETDEWEB)

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

    1969-08-01

    Experimental relationships have been established between the blackening of emulsions by impinging ions and the following parameters: number, mass and energy of impinging particles. Mean energy ions (about twenty keV) give rise to a latent image probably made of small specks of metallic silver located at the surface or in the bulk of the silver halide grain. A specific developer for ion sensitive emulsion was perfected. Sensitivity and detection threshold are increased by a factor of two or three, compared with values observed using a classical developer. Low energy particles sputtered from superficial layers of the emulsion by the impinging twenty keV ions, produce a latent image close to the surface of the silver halide grain. An oxidizing process bleaches superficial latent image and then reduces background fog. The improved signal over background ratio allows to observe lines undetectable when the plates are developed by usual process. (author) [French] On a etabli les relations experimentales entre le noircissement resultant de l'action des ions sur l'emulsion sensible et les parametres suivants: nombre de particules incidentes, masse et energie de ces particules. L'effet sur les grains d'halogenure d'argent a ete examine: les ions d'energie moyenne (de l'ordre de 20 keV) creent une image latente vraisemblablement constituee d'argent, situee a la fois a la surface et a l'interieur du grain. Un revelateur specifique pour le developpement des emulsions sensibles exposees aux ions a ete mis au point: il accroit la sensibilite d'un facteur deux a trois et le facteur de contraste par rapport a un revelateur usuel. Les particules de faible energie, emises par pulverisation des couches superficielles de l'emulsion au cours de l'enregistrement des spectres de masse des ions d'energie moyenne, creent essentiellement dans les grains d'halogenure d'argent, une image latente superficielle, responsable du fond. Un traitement oxydant est propose pour eliminer cette image en

  11. Contribution to the validation of thermal ratchetting prevision methods in metallic structures; Contribution a la validation des methodes de prevision du rochet thermique dans les structures metalliques

    Energy Technology Data Exchange (ETDEWEB)

    Rakotovelo, A.M

    1998-03-01

    This work concerns the steady state assessment in the metallic structures subjected to thermomechanical cyclic loadings in biaxial stress state. The effect of the short time mechanical overloads is also investigated. The first chapter is devoted to a bibliographic research concerning the behaviour of the materials and the structures in the cyclic plasticity. Some works relate to the experimental aspect as well as the numerical one for the steady state assessment of such structures are presented. The experimental part of the study is presented in the second chapter. The experimental device was carried out in order to prescribe tension and torsion forces combined with cyclic thermal loading. Some tests was then carried out, among these tests certain include some overloads in tension or torsion. The last chapter describes the numerical calculations using different models (linear isotropic hardening, linear kinematic hardening and elasto-viscoplastic Chaboche's model) and the application of some simplified methods for the ratchetting assessment in the structures. We have considered two categories of methods. The first one is based on an elastic analysis (Bree's diagram, 3 Sm rule, efficiency rule) and the second one combines elastic analysis and elastoplastic analysis of the first cycle (Gatt's and Taleb's methods). The results of this study have enabled: to validate in the biaxial stress state an expression which takes into account the effect of mechanical short time overloads; to test the performances of considered models to describe the evolution of the structure during the first cycle and to take into account the effect of short time overloads. Among the considered models, the elastoplastic Chaboche's model seems to be the most accurate to describe the structure's behaviour during the first cycles; to validate some simplified methods. Certain methods based only on elastic analysis (Bee's diagram and efficiency rule) seem not

  12. Contribution to the development of new analytical methods by the coupling between capillary electrophoresis and mass spectrometry (ICP-MS and ESI-MS): applications to the nuclear and biological fields; Contribution au developpement de nouvelles methodes analytiques par le couplage entre l'electrophorese capillaire et la spectrometrie de masse (ICP-MS et ESI-MS): applications dans les domaines nucleaires et biologiques

    Energy Technology Data Exchange (ETDEWEB)

    Pitois, A

    2006-04-15

    The coupling between chromatographic and electrophoretic separation techniques and mass spectrometry is used to combine the efficiency of the separation technique to the selectivity and sensitivity of the detectors. In this work, the number of applications of the CE-MS couplings has been increased. New analytical methods have been set up in the nuclear and biological fields. New analytical methods for the determination of fission products (cesium and lanthanides) have been developed by CE-ICP-MS. They enable to determine both concentration and isotopic composition of the fission products for very low detection limits (ng/mL by CE-Q-ICPMS, pg/mL by CE-HR-ICP-MS), since all the isobaric interferences are resolved. Moreover, only some nano-liters of sample are necessary to perform the analysis. These method have been applied with success to a simulated sample of spent fuel, to a nuclear sample from PUREX process and to a leaching of MOX fuel. Then, lanthanides have been analysed by CE-ESI-MS and the capability of ESI-MS to provide structural information has been studied. Elementary information has been obtained for strong potentials. Structural information has been obtained for low potentials. Finally, a new analytical method by CE-ESI-MS for the determination of 10B-boronophenylalanine (10B-BPA) has been developed for Boron Neutron Capture Therapy (BNCT). It has been applied to the cellular lines F98 and HUVEC. This CE-ESI-MS method has been validated by HR-ICP-MS. It enables a direct quantification of the chemical form 10B-BPA in samples of limited size (some nano-liters) and for low concentrations (ng/mL). As a consequence, this CE-ESI-MS method has enabled the study of the kinetics of 10B-BPA release and uptake for the F98 cells. (author)

  13. Determination of detection limits for a VPD ICPMS method of analysis; Determination des limites de detection d'une methode d'analyse VPD ICPMS

    Energy Technology Data Exchange (ETDEWEB)

    Badard, M.; Veillerot, M

    2007-07-01

    This training course report presents the different methods of detection and quantifying of metallic impurities in semiconductors. One of the most precise technique is the collection of metal impurities by vapor phase decomposition (VPD) followed by their analysis by ICPMS (inductively coupled plasma mass spectrometry). The study shows the importance of detection limits in the domain of chemical analysis and the way to determine them for the ICPMS analysis. The results found on detection limits are excellent. Even if the detection limits reached with ICPMS performed after manual or automatic VPD are much higher than detection limits of ICPMS alone, this method remains one of the most sensible for ultra-traces analysis. (J.S.)

  14. Gestion des risques

    CERN Document Server

    Louisot, Jean-Paul

    2009-01-01

    Depuis le début du lie siècle, la gestion des risques connaît une véritable révolution culturelle. Jusqu'alors fonction technique, centrée autour de l'achat de couverture d'assurances, elle est devenue une discipline managériale et transversale : une valise d'instruments que chaque manager doit connaître et appliquer quels que soient son domaine de compétence et ses missions au sein de l'organisation. En effet, la gestion des risques est une culture qui doit être assimilée par chacun des acteurs. C'est précisément l'ambition des 101 questions rassemblées dans cet ouvrage : apporter à chaque manager d'entreprise, de collectivité, d'établissement de santé..., des réponses claires au " pourquoi " et au " comment " : Comment identifier les risques ? Comment analyser les risques ? Quels sont les objectifs de la gestion des risques ? Une carte des risques pour quoi faire ? Pourquoi faut-il financer les risques ? Les entreprises ont-elles des responsabilités pénales ? En quoi consiste la gestion...

  15. Decommissioning and dismantling: Qualification of the gamma scanning method as a certified method for radiological decontrolling measurement. Final report; Stillegung und Rueckbau: Qualifizierung des Gamma-Scanning zur Freimessung. Genehmigungspraxis. Abschlussbericht

    Energy Technology Data Exchange (ETDEWEB)

    Kirchhoff, J.; Stasch, W.P.

    1998-10-01

    Prior to release from the radiological supervision and control regime of the AtG (German Atomic Energy Act), nuclear facilities have to be scanned using licensed radioactivity measuring methods for providing evidence that the remaining radioactive contamination is below the legally defined limits and excludes hazards to the population, material goods, or the environment. The manually performed {alpha}/{beta} measuring methods applied so far for radiological decontrolling measurement are surface scanning methods measuring the contamination of very thin surface layers of the structures, while radioactivity in deeper layers is not necessarily detected. The gamma scanning method presented in this document is capable of scanning the structures and materials of nuclear facilities from the surface down to much deeper layers in just one measuring run. The automated scanning process at the same time offers the advantage of preventing the uncertainties possibly contributed through human factors. (orig./CB) [Deutsch] Vor der Entlassung von kerntechnischen Anlagen aus dem Geltungsbereich des AtG ist sicherzustellen, dass von der Anlage nach Freigabe aus der atomrechtlichen Ueberwachung keine Gefahren fuer Personen, Sachgueter und die Umwelt ausgehen koennen. Hierzu sind die Anlagen freizumessen, d.h. es ist durch qualifizierte Messverfahren sicherzustellen, dass festgelegte radiologische Grenzwerte unterschritten werden. Die bisherigen auf {alpha}/{beta}-Messung beruhenden Freimessverfahren (Kontaminationsmonitore) erfassen nur die Radioaktivitaet in duennsten Oberflaechenschichten. Radioaktivitaet in darunter liegenden Schichten wird nicht zwangslaeufig erfasst. Zudem erfolgen diese Messungen ausschliesslich manuell. Das Gamma-Scanning-Freimessverfahren erfasst neben der Oberflaechenschicht gleichzeitig auch tiefere Schichten. Der Nachweis der Grenzwertunterschreitung kann somit in nur einem Arbeitsgang erbracht werden. Durch automatisiertes Scannen koennte darueber hinaus

  16. La gouvernance des risques naturels et la problematique des ...

    African Journals Online (AJOL)

    Depuis quelques années, la gouvernance des risques naturels dus aux inondations remet en cause les processus de mise en oeuvre des politiques urbaines et la qualité de la structure des aménagements dans les grandes villes du Golfe de Guinée. La perception de la gouvernance et l'application des politiques de ...

  17. Utilisation des mousses et des pâtes syntactiques pour combler les lacunes des poteries archéologiques

    Directory of Open Access Journals (Sweden)

    Viviane Bechoux

    2008-10-01

    Full Text Available Filling potteries missing parts with plaster raises now complex problems during the de-restoration treatments. Ceramics restorers have recurrently questions on the use of plaster in the field of archaeological ceramics restoration. Some researches point to the choice of other filling materials. At the present time other methods can be devised by proposing plaster replacement by a lightened composite material: syntactic foams and pastes.Le comblement des lacunes des poteries à partir du plâtre pose actuellement des problèmes complexes lors des traitements de dérestauration. Les restaurateurs de céramiques s'interrogent de manière récurrente sur l'utilisation du plâtre dans le domaine de la restauration des céramiques archéologiques. Des recherches s'orientent vers le choix d'autres matériaux d'obturation. Actuellement, d'autres méthodes peuvent être mises en place en proposant le remplacement du plâtre par un matériau composite allégé, les mousses et les pâtes syntactiques.

  18. The construction of standardised equipment expressly adapted to the different methods of radiation control; Realisation de materiel standardise specialement adapte aux divers modes de controle des radiations

    Energy Technology Data Exchange (ETDEWEB)

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

    1960-07-01

    The authors show what general characteristics must have equipment designed for radiation control. This equipment must make possible the measurement of doses corresponding to 1/10 of the maximum permissible limit. It should be designed for a specific purpose, and finally it should be independent as far as possible. The authors review the different types of control which it is necessary to effect. (author) [French] Les auteurs indiquent quelles doivent etre les caracteristiques generales du materiel de controle des radiations. Ce materiel doit permettre l'appreciation de mesures correspondant au 1/10{sup e} des limites maximales admissibles. Il devrait etre concu pour une fonction determinee, enfin, il doit etre dans la mesure du possible, autonome. Les auteurs passent en revue les differents types de controle qu'il est necessaire de couvrir. (auteur)

  19. Les méthodesthermiques de production des hydrocarbures. Chapitre 1 : transfert de chaleur et de masse Thermal Methods of Hydrocarbon Production. Chapter 1 : Heat and Mass Transfer

    Directory of Open Access Journals (Sweden)

    Bia P.

    2006-11-01

    Full Text Available Après un rappel général sur le transfert de chaleur et de masse ainsi que sur les lois de conservation dans les milieux continus, on traite de l'adaptation de ces lois au cas des milieux poreux. On donne ensuite des informations quantitatives sur les grandeurs physiques mises en jeu par les phénomènes de transfert en milieu poreux. After making a general review of heat and mass transfer a well as of laws of conservation in continua, this chapter describes how these laws con be adopted to the case of porous media. Quantitative data are then given on the physical magnitudes brought into play by transfer phenomena in porous media.

  20. Contribution to the study of light nuclei with polarized deuterons; Contribution a l'etude des noyaux legers au moyen de deutons polarises

    Energy Technology Data Exchange (ETDEWEB)

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

    1967-04-15

    We describe roughly the vector and tensor-polarized deuteron source associated with the Saclay fixed energy (22 MeV) cyclotron. This has been used to measure the deuteron asymmetry in d-{alpha} scattering (between 17.7 and 21.4 MeV) and in d-p scattering at 21.7 MeV. Then we develop the formalism of irreducible tensor operators used to describe the polarization of a particle of given spin and we study the helicity formalism used to describe the scattering amplitudes for scattering of deuterons by {alpha} (spin 0) and protons (spin 1/2). We apply the preceding results to the phase shift analysis of scattering cross-sections and: 1) deuteron polarization in d-{alpha} scattering from 10 to 27 MeV from which we obtain indications about the excited states of {sup 6}Li; 2) proton and deuteron polarizations in p-d (or d-p) scattering from 1.5 to 12 MeV so as to get the splitting (due to spin interactions) of P and D waves. (author) [French] On decrit sommairement la source de deutons polarises vectoriellement et tensoriellement associee au cyclotron a energie fixe de Saclay avec laquelle on a mesure l'asymetrie des deutons dans la diffusion d-{alpha} de 17,7 a 21,4 MeV et d-p a 21,7 MeV. Puis or developpe le formalisme des operateurs tensoriels irreductibles utilise pour decrire la polarisation d'une particule de spin quelconque. On etudie ensuite le formalisme de l'helicite dans lequel on etudie la diffusion elastique des deutons diffuses par des particules {alpha} (spin 0) et des protons (spin 1/2). On applique les resultats precedents a l'analyse en dephasages de la section efficace et des polarisations: 1 )des deutons dont la diffusion d-{alpha} de 10 a 27 MeV destinee a donner des indications sur les niveaux excites de {sup 6}Li; 2) des protons et des deutons dans la diffusion p-d de 1,5 a 12 MeV en vue de l'etude de la separation suivant les differentes valeurs du moment total J, des ondes P et D (separation due aux interactions de spin). (auteur)

  1. Kinetic ion exchange studies in ultramarines by the radioactive tracer method; Etudes cinetiques d'echanges d'ions dans les outremers par la technique des traceurs radioactifs

    Energy Technology Data Exchange (ETDEWEB)

    May, S; Goenvec, H; Pinte, G [Commissariat a l' Energie Atomique, Saclay (France).Centre d' Etudes Nucleaires

    1960-07-01

    The possibility of ion exchanges in various ultramarines has been studied in the aqueous phase. The kinetics of the exchange reactions is followed by studying the behaviour of a radioactive ion, either in the solution of the exchanging salt or in the ultramarine itself. The sodium in the make-up of the ultramarine, is found to exchange with various ions in solution. The reaction speeds appear to be governed by a diffusion process inside the grains of ultramarine. The diffusion coefficients and the activation energies are determined for the exchanges studied. Several exchange studies were carried out in an organic medium. The kinetics of ion exchange is also investigated in ultramarines from which most of the constituent sulphur has been eliminated. The results obtained in these ultramarines are compared with the exchange kinetics of the same ions in ordinary ultramarine. (author) [French] Nous avons etudie la possibilite d'echanges ioniques dans differents outremers, en phase aqueuse. L'etude cinetique des reactions d'echanges est suivie en etudiant le comportement d'ion radioactif, soit dans la solution du sel echangeant, soit dans l'outremer lui-meme. C'est le sodium de constitution de l'outremer qui s'echange avec differents ions en solution. Les vitesses de reactions semblent etre controlees par un processus de diffusion a l'interieur des grains d'outremer. Les coefficients de diffusion et les energies d'activation sont determines pour les echanges etudies. Quelques etudes sont realisees en milieu organique ou quelques echanges ont ete etudies. La cinetique d'echange d'ions est egalement etudie dans des outremers dans lesquels la majorite du soufre de constitution a ete eliminee. On compare les resultats obtenus dans ces outremers avec les cinetiques d'echanges des memes ions dans l'outremer ordinaire. (auteur)

  2. Les effets des interfaces sur les proprietes magnetiques et de transport des multicouches nickel/iron et cobalt/silver

    Science.gov (United States)

    Veres, Teodor

    Cette these est consacree a l'etude de l'evolution structurale des proprietes magnetiques et de transport des multicouches Ni/Fe et nanostructures a base de Co et de l'Ag. Dans une premiere partie, essentiellement bibliographique, nous introduisons quelques concepts de base relies aux proprietes magnetiques et de transport des multicouches metalliques. Ensuite, nous presentons une breve description des methodes d'analyse des resultats. La deuxieme partie est consacree a l'etude des proprietes magnetiques et de transport des multicouches ferromagnetiques/ferromagnetiques Ni/Fe. Nous montrerons qu'une interpretation coherente de ces proprietes necessite la prise en consideration des effets des interfaces. Nous nous attacherons a mettre en evidence, a evaluer et a etudier les effets de ces interfaces ainsi que leur evolution, et ce, suite a des traitements thermiques tel que le depot a temperature elevee et l'irradiation ionique. Les analyses correlees de la structure et de la magnetoresistance nous permettront d'emettre des conclusions sur l'influence des couches tampons entre l'interface et le substrat ainsi qu'entre les couches elles-memes sur le comportement magnetique des couches F/F. La troisieme partie est consacree aux systemes a Magneto-Resistance Geante (MRG) a base de Co et Ag. Nous allons etudier l'evolution de la microstructure suite a l'irradiation avec des ions Si+ ayant une energie de 1 MeV, ainsi que les effets de ces changements sur le comportement magnetique. Cette partie debutera par l'analyse des proprietes d'une multicouche hybride, intermediaire entre les multicouches et les materiaux granulaires. Nous analyserons a l'aide des mesures de diffraction, de relaxation superparamagnetique et de magnetoresistance, les evolutions structurales produites par l'irradiation ionique. Nous etablirons des modeles qui nous aideront a interpreter les resultats pour une serie des multicouches qui couvrent un large eventail de differents comportements magnetiques

  3. Reactivity coefficients by perturbation theory; Calcul des coefficients de re activite par la theorie des perturbations; Koehffitsienty reaktivnosti, opredelennye pri pomoshchi teorii vozmushchenij; Determinacion, de coeficientes de reactividad con ayuda de la teoria de las perturbaciones

    Energy Technology Data Exchange (ETDEWEB)

    Webster, J W [International Atomic Energy Agency, Vienna (Austria)

    1962-03-15

    The development of the formulae of perturbation theory provides a good opportunity to use one of the principal devices of mathematical heuristics, i.e. proceeding by analogy from something that is simple to something that is more complicated. This paper: (a) Reviews the formulation of perturbation theory as a method of calculating reactivity coefficients; this consists mainly of developing the differential equation for the adjoint flux, as a continuous function of position and lethargy, by proceeding by analogy from the one-group differential equation for adjoint flux. (b) Presents an application of the two-group form of perturbation theory to a boiling-mercury-cooled fast-breeder reactor (MCBR). It is seen that the net Hg density coefficient of reactivity for the first-design-try for the MCBR is negative for some regions and positive for others. However, it is negative for regions of highest statistical weight and where the density change for a power change would be the greatest. The overall Hg density coefficient is thus negative, i.e. the void coefficient is positive-an unsafe condition. It can be easily seen from the two-group formulation what design changes had to be made to obtain a design which would have a negative void coefficient. It developed in subsequent investigations that there were such design changes that could be made and a design of the MCBR with a negative void coefficient was eventually achieved. (author) [French] La mise au points des formules de la theorie des perturbations fournit une bonne occasion d'employer en mathematiques une des principales regles de la methode heuristique, celle qui consiste a proceder par analogie du simple au complexe. L'auteur du memoire: a) Expose une methode permettant de calculer les coefficients de reactivite en utilisant les formules de la theorie des perturbations; en substance, cette methode consiste a developper l'equation differentielle relative au flux adjoint en fonction continue de la position et de la

  4. The fortran programme for the calculation of the absorption and double scattering corrections in cross-section measurements with fast neutrons using the monte Carlo method (1963); Programme fortran pour le calcul des corrections d'absorption et de double diffusion dans les mesures de sections efficaces pour les neutrons rapides par la methode de monte-carlo (1963)

    Energy Technology Data Exchange (ETDEWEB)

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

    1963-07-01

    A calculation for double scattering and absorption corrections in fast neutron scattering experiments using Monte-Carlo method is given. Application to cylindrical target is presented in FORTRAN symbolic language. (author) [French] Un calcul des corrections de double diffusion et d'absorption dans les experiences de diffusion de neutrons rapides par la methode de Monte-Carlo est presente. L'application au cas d'une cible cylindrique est traitee en langage symbolique FORTRAN. (auteur)

  5. Study of the texture of porous solids using a technique of {gamma} ray absorption; Application de l'absorption du rayonnement {gamma} a l'etude de la texture des solides poreux

    Energy Technology Data Exchange (ETDEWEB)

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

    1967-01-01

    A technique, which enables us to measure locally total porosity, open porosity and pore size distribution is developed. The total porosity is calculated from the bulk density. A gamma absorption gauge is set up fitted with a Cs137 source. This enables the determination of the density by layers of carbonaceous samples in a practically automatic way. By taking adequate precautions it is possible to obtain the density with a maximum error {delta}{rho} {<=} 0,005 g/cm{sup 3}. The open porosity is evaluated by the absorption method after impregnation with bromoform. A new mercury porosimeter is developed using the absorption probe for the measurement of mercury infiltrated into the porous sample. Due to the localized character of exploration by this technique, the variations of porous texture in a heterogeneous sample can be studied. Used as a classical porosimeter, in the case of homogeneous samples, this apparatus is capable of exploring the equivalent diameters of pores between 500 {mu} and 0.14 {mu} with a maximum error {delta}P {<=} 0.002. The possibility of exploration of heterogeneous samples, with the facility of determination of porosities due to macro-pores combined with the non-limiting character of the method in the field of high pressures differentiates this apparatus from all the porosimeters of former conception. Examples of utilization of this technique in the case of graphite-gas reactions are presented. (author) [French] On a developpe une technique permettant la mesure localisee de la porosite totale, de la porosite ouverte et de la repartition de la taille de pores. La porosite totale est calculee a partir de la densite apparente. On a mis au point une jauge d'absorption du rayonnement gamma munie d'une source de Cs137. Celle-ci nous a permis de determiner la densite par couches d'echantillons cylindriques carbones d'une facon pratiquement automatique. En prenant les precautions adequates, il est possible d'obtenir la densite

  6. Study of the texture of porous solids using a technique of {gamma} ray absorption; Application de l'absorption du rayonnement {gamma} a l'etude de la texture des solides poreux

    Energy Technology Data Exchange (ETDEWEB)

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

    1967-01-01

    A technique, which enables us to measure locally total porosity, open porosity and pore size distribution is developed. The total porosity is calculated from the bulk density. A gamma absorption gauge is set up fitted with a Cs137 source. This enables the determination of the density by layers of carbonaceous samples in a practically automatic way. By taking adequate precautions it is possible to obtain the density with a maximum error {delta}{rho} {<=} 0,005 g/cm{sup 3}. The open porosity is evaluated by the absorption method after impregnation with bromoform. A new mercury porosimeter is developed using the absorption probe for the measurement of mercury infiltrated into the porous sample. Due to the localized character of exploration by this technique, the variations of porous texture in a heterogeneous sample can be studied. Used as a classical porosimeter, in the case of homogeneous samples, this apparatus is capable of exploring the equivalent diameters of pores between 500 {mu} and 0.14 {mu} with a maximum error {delta}P {<=} 0.002. The possibility of exploration of heterogeneous samples, with the facility of determination of porosities due to macro-pores combined with the non-limiting character of the method in the field of high pressures differentiates this apparatus from all the porosimeters of former conception. Examples of utilization of this technique in the case of graphite-gas reactions are presented. (author) [French] On a developpe une technique permettant la mesure localisee de la porosite totale, de la porosite ouverte et de la repartition de la taille de pores. La porosite totale est calculee a partir de la densite apparente. On a mis au point une jauge d'absorption du rayonnement gamma munie d'une source de Cs137. Celle-ci nous a permis de determiner la densite par couches d'echantillons cylindriques carbones d'une facon pratiquement automatique. En prenant les precautions adequates, il est possible d'obtenir la densite avec une erreur maximale

  7. Some Possibilities of Radiation Polymerization from the Gaseous Phase on Solid Bases; Possibilites de polymerisation radiochimique en phase gazeuse sur des lits de matiere solide; O nekotorykh vozmozhnostyakh radiatsionnoj polimerizatsii iz gazovoj fazy na tverdykh podlozhkakh; Perspectivas de la radiopolimerizacion en fase gaseosa sobre lechos de sustancias solidas

    Energy Technology Data Exchange (ETDEWEB)

    Tsetlin, B. L.

    1963-11-15

    The unusual feature of graft polymer synthesis by solid ''bed'' irradiation in the presence of monomer vapours is that the activation centres initiating polymerization are in practice generated only on the bed; transmission of the kinetic chain to the monomer is impeded and new polymer chains grow only under the influence of the solid bed molecular forces. These features of gas phase processes enlarge the scope of the graft polymer technique, making it applicable to inorganic beds and usable in the synthesis of mineral organic products. If stretched synthetic fibres are used as a bed, on the other hand, their orientated macromolecules control the growth of new polymer chains and the graft polymer is formed directly as an orientated structure. Two-component combined fibres are formed as a result and the fibre-bed and ''grafted'' fibre may in appropriate circumstances each display their own particular complex of mechanical properties. (author) [French] La synthese des polymeres greffes par irradiation de ''lits'' de matiere solide en presence de vapeur de monomeres en voie de polymerisation presente les particularites suivantes: les centres actifs qui amorcent la polymerisation ne se forment pratiquement qu'a la surface du ''lit''; le transfertau monomere de la chaine en mouvement est rendu plus difficile; les nouvelles chafnes du polymere se developpent sous l'action unilaterale des forces moleculaires de la surface solide. Ces particularites du processus en phase gazeuse elargissent les possibilites qu'offre la methode de la polymerisation par greffage. La methode peut alors etre egalement appliquee aux lits non organiques et servir a la synthese de composes organomineraux. En revanche, lorsqu'on utilise comme lits des fibres synthetiques allongees, les macromolecules orientees de ces dernieres dirigent la croissance des nouvelles chaines du polymere de sorte que le polymere greffe se forme directement a l'etat oriente. On obtient ainsi des fibres cominees a deux

  8. Simulated annealing method for electronic circuits design: adaptation and comparison with other optimization methods; La methode du recuit simule pour la conception des circuits electroniques: adaptation et comparaison avec d`autres methodes d`optimisation

    Energy Technology Data Exchange (ETDEWEB)

    Berthiau, G

    1995-10-01

    The circuit design problem consists in determining acceptable parameter values (resistors, capacitors, transistors geometries ...) which allow the circuit to meet various user given operational criteria (DC consumption, AC bandwidth, transient times ...). This task is equivalent to a multidimensional and/or multi objective optimization problem: n-variables functions have to be minimized in an hyper-rectangular domain ; equality constraints can be eventually specified. A similar problem consists in fitting component models. In this way, the optimization variables are the model parameters and one aims at minimizing a cost function built on the error between the model response and the data measured on the component. The chosen optimization method for this kind of problem is the simulated annealing method. This method, provided by the combinatorial optimization domain, has been adapted and compared with other global optimization methods for the continuous variables problems. An efficient strategy of variables discretization and a set of complementary stopping criteria have been proposed. The different parameters of the method have been adjusted with analytical functions of which minima are known, classically used in the literature. Our simulated annealing algorithm has been coupled with an open electrical simulator SPICE-PAC of which the modular structure allows the chaining of simulations required by the circuit optimization process. We proposed, for high-dimensional problems, a partitioning technique which ensures proportionality between CPU-time and variables number. To compare our method with others, we have adapted three other methods coming from combinatorial optimization domain - the threshold method, a genetic algorithm and the Tabu search method - The tests have been performed on the same set of test functions and the results allow a first comparison between these methods applied to continuous optimization variables. (Abstract Truncated)

  9. Burst slug detection system in french power reactors (1961); La detection des ruptures de gaines dans les reacteurs de puissance francais (1961)

    Energy Technology Data Exchange (ETDEWEB)

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

    1961-07-01

    Gas samples are taken from the channels of the reactor and the short lived fission products are electrostatically collected to be analysed by a phosphor and photomultiplier system. The electrostatic collection and rotating electrode detector is described and its main uses exposed. Experience has shown the interest of measuring the evolution of fission products activities and not their absolute value only. In this way, data processing equipment have been designed and adapted to the detection apparatus. The system developed and realized for the G-l - G-2 - G-3 - EDF-1 - EDF-2 reactors are compared. (authors) [French] Un prelevement de gaz est effectue dans les canaux du reacteur et les produits de fission a vie courte sont collectes electrostatiquement pour etre analyses par un ensemble scintillateur-photomultiplicateur. Le detecteur a collection electrostatique et electrode tournante est decrit et ses applications principales sont exposees. L'experience a montre l'interet de mesurer l'evolution des activites en produits de fission et non seulement leur valeur absolue. D'ou le developpement d'ensembles de traitement des informations associes aux chaines de detection. Comparaison des realisations sur les reacteurs G-l - G-2 - G-3 - EDF-1 et EDF-2. (auteurs)

  10. Dental magnetic resonance tomography (dental-MRT) as a method for imaging of the maxillo-mandibular bone; Dentale Magnetresonanztomographie (Dental-MRT) als Verfahren zur Darstellung des maxillomandibulaeren Zahnhalteapparates

    Energy Technology Data Exchange (ETDEWEB)

    Gahleitner, A.; Nasel, C.; Schick, S.; Dorffner, S.; Imhof, H.; Trattnig, S. [Wien Univ. (Austria). Abt. fuer Osteologie; Bernhart, T.; Mailath, G.; Watzek, G. [Wien Univ. (Austria). Abt. fuer Orale Chirurgie

    1998-10-01

    Purpose: To establish a new method for dental imaging using magnetic resonance tomography named Dental-MRT and to demonstrate its usefulness in diagnosing dentogen pathologies of the mandible and maxilla. Methods: Seven healthy volunteers, three patients with pulpitis, two patients with dentigerous cysts, two patients after tooth transplantation, and three patients with atrophic mandibles have been evaluated. Optimized axial T{sub 1}- and T{sub 2}-weighted gradient echo and spin echo sequences in 2D and 3D technique have been established to perform studies of the jaws. The acquired images were reconstructed with a standard dental software package on a workstation as panorama and cross-sectional views of the mandible or maxilla. Results: The entire maxillo-mandibular bone, teeth, dental pulp, and the content of the mandibular canal were well depicted. Patients with pulpitis demonstrate bone marrow edema in the periapical region. Dentigerous cysts and their relation to the surrounding structures are clearly shown. After contrast media administration marked enhancement of the dental pulp can be demonstrated. Conclusion: Dental-MRT promises to provide a new tool for visualization and detection of dental diseases. (orig.) [Deutsch] Ziel: Das Vorstellen der Dental-MRT als neue Methode zur Darstellung des Ober- und Unterkiefers und ihre Anwendung bei der Diagnose zahnmedizinischer Erkankungen. Methoden: 7 gesunde Probanden, drei Patienten mit Pulpitis, zwei Patienten mit odontogenen Zysten, zwei Patienten nach Zahntransplantationen und drei Patienten mit atrophem Unterkiefer wurden untersucht. Optimierte axiale T{sub 1}- und T{sub 2}-gewichtete Gradienten-Echo- und Spin-Echo-Sequenzen in 2D und 3D-Technik wurden angewandt. Nach der Untersuchung wurden Panoramaschnitte und dentale Rekonstruktionen des Ober- und Unterkiefers, unter Verwendung einer gebraeuchlichen Dental-Software, angefertigt. Ergebnisse: Der gesamte Kieferbereich, Zaehne, Pulpa und der Inhalt des

  11. Heat management in motor vehicles 3. Development methods and innovations in heat management in passenger cars and industrial vehicles; Waermemanagement des Kraftfahrzeugs 3. Entwicklungsmethoden und Innovationen der Kfz- und Nfz-Waermetechnik

    Energy Technology Data Exchange (ETDEWEB)

    Deussen, N. (ed.) [Fachhochschule Koeln (Germany). Labor fuer Verbrennungsmotoren und Applikation

    2002-07-01

    The proceedings volume outlines problem solutions, development strategies and design methods relating to heat management in motor vehicles. The focus is on utilisation, supply, transmission and release of heat in passenger cars and industrial vehicles. The complete state of the art is reviewed, with the focus on the following subjects: The potential of heat management in terms of performance and comfort; Future strategies for optimisation of thermal processes; Expert knowledge in component and system innovations; Status and perspectives of user software; Engine cooling, vehicle air conditioning, heat protection; Methodology; Numeric fluid mechanics; Heat transfer; Practical applications of thermal engineering, Heat management in engines; Thermal system optimisation; CFD; Future numeric methods in heat transfer and fluid mechanics; Methods of measurement and instrumentation. [German] Der Tagungsband informiert in einem aktuellen Ueberblick ueber Problemloesungen, Entwicklungsstrategien und Auslegungsmethoden im Umfeld des Kraftfahrzeug-Waermemanagements. Dabei wird insbesondere auf die Optimierung der Nutzung, Bereitstellung, Uebertragung und Abgabe von Waerme fokussiert. Der Inhalt umfasst dabei Anwendungen bei Automobilen und Nutzfahrzeugen. Der Leser erhaelt einen konkreten Ueberblick ueber die Trends auf neuestem Stand der Technik. Besondere Schwerpunkte sind: Potenzial des Waermemanagements bezueglich Leistung und Kundennutzen - Zukunftsweisende Strategien zur Optimierung waermetechnischer Prozesse - Kompaktes Fachwissen bei Bauteil- und System-Innovationen - Stand der Technik und Zukunftsperspektive bei Anwendersoftware. Inhalt: Motorkuehlung - Fahrzeugklimatisierung - Hitzeschutz - Methoden der Waermetechnik - Numerische Stroemungsmechanik - Waermeuebertragung - Anwendungsbeispiele der Waermetechnik - Motor-Thermomanagement - Waermetechnische Systemoptimierung - CFD - Zukuenftige numerische Methoden der Waermeuebertragung und Stroemungsmechanik - Messtechnik

  12. Photonique des Morphos

    CERN Document Server

    Berthier, Serge

    2010-01-01

    La photonique est déjà présente dans notre vie quotidienne, et on attend maintenant que la manipulation des photons permette aussi le traitement logique des informations. Cependant, l’élément de base qui permet cette manipulation de la lumière, le cristal photonique, est d’une réalisation complexe et mal contrôlée. Dans la course à la maîtrise de la lumière, les structures photoniques naturelles ont beaucoup à nous apprendre. C’est ce que nous montre Serge Berthier qui étudie dans ce livre la structure des écailles des Morphos. Tenant compte de l’essor récent des approches biomimétiques, il présente de manière détaillée plus de dix-huit techniques expérimentales utilisées pour ses analyses, ainsi que les diverses approches théoriques développées pour la modélisation de structures multi-échelles complexes. Première étude quasi-exhaustive des structures fines d’un genre et des propriétés optiques ainsi que colorimétriques générées, ce livre fournit aux entomologiste...

  13. Droit des organisations internationales

    CERN Document Server

    Sorel, Jean-Marc; Ndior, Valère

    2013-01-01

    Cet ouvrage collectif offre aux enseignants et chercheurs en droit international, aux praticiens et aux étudiants, une analyse actualisée du droit des organisations internationales. Il dresse en cinq parties un tableau, illustré par des exemples variés, des problématiques que soulève le phénomène polymorphe d institutionnalisation de la société internationale. La première partie est consacrée au phénomène des « organisations internationales », sous l angle à la fois de l institutionnalisation progressive des relations internationales et de la difficulté à cerner une catégorie unifiée. La deuxième partie rend compte de la création, de la disparition et des mutations des organisations internationales, ici envisagées comme systèmes institutionnels et ordres juridiques dérivés. La troisième partie analyse l autonomie que l acquisition de la personnalité juridique et de privilèges et immunités, un organe administratif intégré, un personnel ou un budget propres confèrent aux organi...

  14. 205 Le Role de la Litterature dans le Developpement de la Nation ...

    African Journals Online (AJOL)

    Ike Odimegwu

    du plaisir en même temps qu'il le moralise. Elle fait naître dans ses lecteurs ou dans son audience des .... développement de l'esprit>>(319)Par cette définition nous comprenons que le développement signale qu'il du progrès ... qu'elle est une œuvre de l'imagination qui aide l'homme à transcender le monde physique.

  15. Frontal and band displacement chromatography of the hydrogen isotopes on palladium; Chromatographies frontale et de deplacement de bande des isotopes de l'hydrogene sur palladium

    Energy Technology Data Exchange (ETDEWEB)

    Botter, F.; Menes, J.; Tistchenko, S.; Dirian, G. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1964-07-01

    As a result of hydrogen isotope separations which we have carried out on supports containing palladium, we believe that we can now make a double contribution, theoretical and experimental, to the work which has already been published in this field. From the fundamental point of view we have developed and studied the validity of a simple model, in our particular case of a separation coefficient {alpha} which is very different to unity. This model, which is of a counter-current isotopic exchange, neglects the longitudinal diffusion in the gas phase and the lateral diffusion in the adsorbed phase and only takes into account the surface resistance to exchange between the phases. It is therefore possible to estimate the efficiency of a chromatography column in terms of the height equivalent of a theoretical plate (HETP). The slight differences observed between the actual chromatograms and the simple model justify both the research undertaken into a more complex model taking into account the diffusion, and the adoption of a simple model for comparing the efficiency of several columns. We describe also a new and simple graphical method for deducing the number of theoretical plates of a column in chromatograms of the frontal and band displacement types. Experimentally we give in particular the criteria for the validity of the model used, the law as a function of the {sup {alpha}}H{sub 2}-HD temperature, the study of the HETP as a function of the various parameters on several palladium containing supports, and the possibilities of an application to preparative chromatography. (authors) [French] Grace aux separations des isotopes de l'hydrogene que nous avons realisees sur masses palladiees, nous pensons apporter aux etudes precedemment publiees dans ce domaine, une double contribution, theorique et experimentale. Du point de vue fondamental, on a developpe et etudie la validite d'un modele simple, dans notre cas particulier d'un coefficient de separation

  16. Frontal and band displacement chromatography of the hydrogen isotopes on palladium; Chromatographies frontale et de deplacement de bande des isotopes de l'hydrogene sur palladium

    Energy Technology Data Exchange (ETDEWEB)

    Botter, F; Menes, J; Tistchenko, S; Dirian, G [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1964-07-01

    As a result of hydrogen isotope separations which we have carried out on supports containing palladium, we believe that we can now make a double contribution, theoretical and experimental, to the work which has already been published in this field. From the fundamental point of view we have developed and studied the validity of a simple model, in our particular case of a separation coefficient {alpha} which is very different to unity. This model, which is of a counter-current isotopic exchange, neglects the longitudinal diffusion in the gas phase and the lateral diffusion in the adsorbed phase and only takes into account the surface resistance to exchange between the phases. It is therefore possible to estimate the efficiency of a chromatography column in terms of the height equivalent of a theoretical plate (HETP). The slight differences observed between the actual chromatograms and the simple model justify both the research undertaken into a more complex model taking into account the diffusion, and the adoption of a simple model for comparing the efficiency of several columns. We describe also a new and simple graphical method for deducing the number of theoretical plates of a column in chromatograms of the frontal and band displacement types. Experimentally we give in particular the criteria for the validity of the model used, the law as a function of the {sup {alpha}}H{sub 2}-HD temperature, the study of the HETP as a function of the various parameters on several palladium containing supports, and the possibilities of an application to preparative chromatography. (authors) [French] Grace aux separations des isotopes de l'hydrogene que nous avons realisees sur masses palladiees, nous pensons apporter aux etudes precedemment publiees dans ce domaine, une double contribution, theorique et experimentale. Du point de vue fondamental, on a developpe et etudie la validite d'un modele simple, dans notre cas particulier d'un coefficient de separation {alpha} tres

  17. 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

  18. Evaluation rapide du coût d'un investissement: méthode des modules fonctionnels Quick Evaluation of the Cost of an Investment: the Functional Module Method

    Directory of Open Access Journals (Sweden)

    Bergman J.

    2006-11-01

    'aide d'abaques. Conçue pour être appliquée lors des étapes préliminaires du développement d'un procédé, ou pour l'obtention d'une évaluation rapide, la Méthode des Modules Fonctionnels s'est avérée suffisamment précise pour être aussi utilisée dans l'estimation du coût d'équipements préalablement dimensionnés. The application of statistical multivariate data analysismethods to a wide range of data samples, obtained either directly from private information sources or from a sizing and detailed-estimation software, has led to the development of a new method for the quick evaluation of the cost of an investment. This method is called the Functional Module Method. In the past, several so-called modular design procedures have been proposed. In the present case, however, this is the first attempt known in the field of the use of techniques such as principal-components analysis, principal factor analysis by distance table and multiple linear regression, to develop a modular structure for estimating the cost of an investment. These changes compared to the modular procedure, which has been used to date by the IFP Project Evaluation Department (Manuel d'évaluation économique des procédés, Editions Technip, Paris, 1976, concern the definition and organization of modules capable of being identified in any chemical processing plant. The functional approach in this lcase is based on the unit operating concept of chemical engineering and no longer on a pre-specified equipment basis, for example, so that the so-called functional modules can be created. All that needs to be used is a process flowsheet indicating the principal pieces of equipment; the nature of the products processed; a material balance that is at least overall, and if possible that. is detailed for the essential lines; the mean operating conditions. The results may be obtained either via equations capable of being programmed on a pocket calculator or by using charts, as is described here. The

  19. Santé des adolescents et des jeunes au Burkina Faso : état des ...

    African Journals Online (AJOL)

    Il s'est agi d'une étude évaluative ayant utilisé une revue documentaire associée à une interview des acteurs clés et un atelier de validation et d'identification des interventions pertinentes pour un plan stratégique national. La situation de la santé des adolescents et des jeunes est caractérisée par des grossesses précoces ...

  20. Impact of Emerging NDE-NDI Methods on Aircraft Design, Manufacture and Maintenance (L’Impact des Nouvelles Methodes d’Examen Non Destructif et de Controle Non Destructif (NDE-NDI) sur la Conception, la Fabrication et la Maintenance des Aeronefs)

    Science.gov (United States)

    1990-03-01

    canique et refroidissenent A eau p1Ilot6 par l’autanate de la crmande nun~rIque. - Le banc est tout A fait compatible avec un syst~me d’analyse...SAPIR est un syst~me de traitement et de restitution d’irnages, i1 assure la nun~risation sur 12 bits (512 points par ligne) des signaux requs des...avant ou aprbs le traitement . Lc SAPIR est cmnand6 et configurA par l’utilisateur au moyen d’un terminal de dialogue, et est pourvu d’une liaison rapide

  1. Measurement of the dead time of a G.M. counter and of the secondary emission of the cathode by the method of the delayed coincidences; Mesure du temps mort d'un compteur G.M. et de l'emission secondaire de la cathode par la methode des coincidences retardees

    Energy Technology Data Exchange (ETDEWEB)

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

    1953-07-01

    The dead time of a G.M counter is measured with the method of delayed coincidences. The pulses of the counter that supplies the circuit of coincidences, arrive there, on the one hand, directly, and in the other part, after a known and variable delay. This method permits besides, to study the parasitic impulses coming from the impact of the positive ions on the cathode of the meter. From the results relative to several counters working in various conditions are given. (author) [French] Le temps mort d'un compteur G.M. est mesure a l'aide d'un methode de coincidences retardees. Les impulsions du compteur qui alimentent le circuit de coincidences, y parviennent, d'une part, directement, et, dautre part, apres un retard connu et variable. Cette methode permet de plus, d'etudier les impulsions parasites provenant de l'impact des ions positifs sur la cathode du compteur. Des resultats relatifs a plusieurs compteurs fonctionnant dans des conditions diverses sont donnes. (auteur)

  2. Energy balance of the cathode connection and calculation of the yield of caesium diodes; Bilan des energies dans la connexion de cathode et calcul du rendement dans les diodes a cesium

    Energy Technology Data Exchange (ETDEWEB)

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

    1964-07-01

    The cathode connection is one of the critical elements in the calculation of the yield of caesium diodes. In particular a study is made of the balance of the losses due to the Joule effect, to radiation and to thermal conduction as a function of the shape and the nature of the cathode connection. The internal voltage drop of the diode is obtained from the expression for the total Joule losses of the metallic conductors. The length of the cathode connection is calculated as a function of the losses and the yield is optimized as a function of the relationship existing between the cathodic losses due to thermal conduction and the Joule losses in the connection. The calculations lead to hyper-elliptic integrals which can only be manipulated by series development. The results obtained are approximate. (author) [French] Dans le calcul du rendement des diodes a cesium, la connexion de cathode est l'un des elements critiques. On etudie specialement le bilan des pertes par effet joule, rayonnement et conduction thermique, en fonction de la forme et de la nature de la connexion de cathode. On obtient la chute de tension interne de la diode a partir de l'expression des pertes joules totales dans les conducteurs metalliques. La longueur de la connexion de cathode est calculee en fonction des pertes et l'on optimise le rendement en fonction du rapport qui existe entre les pertes par conduction thermique de la cathode et les pertes joules dans la connexion. Les calculs conduisent a des integrales hyperelliptiques dont la manipulation n'est possible que par des developpements en serie. Les resultats cherches sont approximatifs. (auteur)

  3. Dental Encounter System (DES)

    Data.gov (United States)

    Department of Veterans Affairs — Dental Encounter System (DES) is an automated health care application designed to capture critical data about the operations of VA Dental Services. Information on...

  4. Diethylstilbestrol (DES) and Cancer

    Science.gov (United States)

    ... DES-exposed grandchildren have? Researchers are also studying possible health effects among women and men who are the children ... for unexposed men. In addition, researchers are studying possible health effects on the grandchildren of mothers who were exposed ...

  5. Table des illustrations

    OpenAIRE

    2016-01-01

    Tableaux Dates d’inauguration des grands hôtels japonais entre 1860 et 1945… 19 Histoire, tourisme et hôtellerie en Corée depuis les années 1870… 59-60 Dates d’inauguration des grands hôtels chinois depuis 1863… 84 Les hôtels de luxe et leurs capacités d’hébergement en Corée en 2000… 103 Les flux de personnes suscités par les hôtels « super luxe » de Séoul en 2000… 105 L’activité des grands hôtels à Séoul en 1999 (en wons)… 106 Propriété et gestion des grands hôtels à Séoul en 1999…. 110 La c...

  6. Direction des Publications

    African Journals Online (AJOL)

    Synthese

    potential and surface properties of their mixtures were investigated, in an ... suppose that the electrostatic repulsive interactions between the two anion ... concentration, et de la conformation des ..... proteins and polysaccharides in solutions,.

  7. Relations de Dispersion et Diffusion des Glueballs et des Mesons dans la Theorie de Jauge U(1)(2+1) Compacte

    Science.gov (United States)

    Ahmed, Chaara El Mouez

    Nous avons etudie les relations de dispersion et la diffusion des glueballs et des mesons dans le modele U(1)_{2+1} compact. Ce modele a ete souvent utilise comme un simple modele de la chromodynamique quantique (QCD), parce qu'il possede le confinement ainsi que les etats de glueballs. Par contre, sa structure mathematique est beaucoup plus simple que la QCD. Notre methode consiste a diagonaliser l'Hamiltonien de ce modele dans une base appropriee de graphes et sur reseau impulsion, afin de generer les relations de dispersion des glueballs et des mesons. Pour la diffusion, nous avons utilise la methode dependante du temps pour calculer la matrice S et la section efficace de diffusion des glueballs et des mesons. Les divers resultats obtenus semblent etre en accord avec les travaux anterieurs de Hakim, Alessandrini et al., Irving et al., qui eux, utilisent plutot la theorie des perturbations en couplage fort, et travaillent sur un reseau espace-temps.

  8. Surface integral formulation of Maxwell's equations for simulation of non-destructive testing by eddy currents. Preliminary study on the implementation of the fast multipole method; Formulation integrale surfacique des equations de Maxwell pour la simulation de controles non destructifs par courant de Foucault. Etude preliminaire a la mise en oeuvre de la methode multipole rapide.

    Energy Technology Data Exchange (ETDEWEB)

    Lim, T.

    2011-04-28

    numeriquement un controle non destructif par courants de Foucault (CND-CF), la reponse du capteur peut etre modelisee via une approche semi-analytique par integrales de volume. Plus rapide que la methode des elements finis, cette approche est cependant limitee a l'etude de pieces planes ou cylindriques (sans prise en compte des effets de bords) du fait de la complexite de l'expression de la dyade de Green pour des configurations plus generales. Or, il existe une forte demande industrielle pour etendre les capacites de la modelisation CF a des configurations complexes (plaques deformees, bords de piece...). Nous avons donc ete amenes a formuler differemment le probleme electromagnetique, en nous fixant comme objectif de conserver une approche semi-analytique. La formulation integrale surfacique (SIE) permet d'exprimer le probleme volumique en un probleme de transmission equivalent a l'interface (2D) entre sous-domaines homogenes. Ce probleme est ramene a la resolution d'un systeme lineaire (par la methode des moments) dont le nombre d'inconnues est reduit du fait du caractere surfacique du maillage. Des lors, ce systeme peut etre resolu par un solveur direct pour de petites configurations. Cela nous a permis de traiter plusieurs seconds membres (ie. differentes positions de capteurs) pour une seule inversion de la matrice d'impedance. Les resultats numeriques obtenus au moyen de cette formulation concernent des plaques avec la prise en compte des effets de bords tels que l'arete et le coin. Ils sont en accord avec des resultats obtenus par la methode des elements finis. Pour des configurations de grandes tailles, nous avons mene une etude preliminaire a l'adaptation d'une methode d'acceleration du produit matrice-vecteur intervenant dans un solveur iteratif (methode multipole rapide, ou FMM) afin de definir les conditions dans lesquelles le calcul FMM fonctionne correctement (precision, convergence...) dans le contexte CND

  9. Perancangan Enkripsi Pada Citra Bitmap Dengan Algoritma Des, Triple Des, dan Idea

    Directory of Open Access Journals (Sweden)

    Agustinna Yosanny

    2010-12-01

    Full Text Available Rapid development of Information Technology causes information can access easier without space boundaries. Image is a form of information, which contains many information. Some image contains confidential information that cannot distribute to unauthorized persons. Therefore, image encryption application is create to encrypt part of image that has confidential information. The image encryption application is encrypt image by applying DES, Triple DES, and IDEA algorithms. The research was applying analysis and design methodology. The analysis methodology was undertaken through literature study and algorithm research and testing. The design methodology was undertaken through database, features, system, and screen layout design. Results of the research are image encryption application that can encrypt part of image and or all of image by applying three algorithms such as DES, Triple DES, and IDEA. This application is show comparation of these algorithms. In conclusion, method of encryption can apply to image, so that confidential information of the image can protect from unauthorized person. 

  10. Investigation of the spatial structure of des-Gly9-[Arg8]vasopressin by the methods of two-dimensional NMR spectroscopy and theoretical conformational analysis

    International Nuclear Information System (INIS)

    Shenderovich, M.D.; Sekatsis, I.P.; Liepin'sh, E.E.; Nikiforovich, G.V.; Papsuevich, O.S.

    1986-01-01

    An assignment of the 1 H NMR signals of des-Gly 9 -[Arg 8 ]vasopressin in dimethyl sulfoxide has been made by 2D spectroscopy. The SSCCs and temperature coefficients Δδ/Δ T have been obtained for the amide protons and the system of NOE cross-peaks in the two-dimensional NOESY spectrum has been analyzed. The most important information on the spatial structure of des-Gly 9 -[Arg 8 ]vasopressin is given by the low value of the temperature coefficient Δδ/Δ T of the Asn 5 amide proton and the NOE between the α-protons of Cys 1 and Cys 6 . It is assumed that the screening of the NH proton of the Asn 5 residue from the solvent is connected with a β-bend of the backbone in the 2-5 sequence, and the distance between the C/sup α/H atoms of the Cys 1 and Cys 6 residues does not exceed 4 A. Bearing these limitations in mind, a theoretical conformational analysis of the molecule has been made. The group of low-energy conformations of the backbone obtained has been compared with the complete set of NMR characteristics

  11. La revolution des savants

    CERN Document Server

    Chavanne, A

    1989-01-01

    Premiere cassette : - 1666 : impact de la creation de l'Academie des Sciences par Colbert, trente ans apres le proces de Galile, et au moment des disparitions de Pascal, Descartes et Fermat. Elle dirigee par le hollandais Huyggens jusqu'a sa fuite de France au moment de la revocation de l'Edit de Nantes. - 1750 : l'Encyclopedie (ou "Dictionnaire raisonne des Sciences, des Arts et des Metiers") de Diderot et d'Alembert, soutenus par Malherbes, Buffon, Condorcet et Rousseau. - 1789 : Revolution francaise. - 8 aout 1793 : l'Assemblee, par une declaration de Marat, dissout l'Academie des Sciences. Celle-ci continue cependant ses travaux pour les poids et mesures jusqu'en 1795. - la Terreur : la condamnation a mort, pas au nom d'une "Revolution qui n'a pas besoin de savants" mais pour d'autres raisons, de trois grands hommes de science : Lavoisier, Bailly et Condorcet. - 1793-1794 : Au printemps 93, le Comite de Salut Publique s'inquiete du demi-million de soldats etrangers de toutes les pays frontaliers qui essai...

  12. Algorithmes de couplage RANS et ecoulement potentiel

    Science.gov (United States)

    Gallay, Sylvain

    Dans le processus de developpement d'avion, la solution retenue doit satisfaire de nombreux criteres dans de nombreux domaines, comme par exemple le domaine de la structure, de l'aerodynamique, de la stabilite et controle, de la performance ou encore de la securite, tout en respectant des echeanciers precis et minimisant les couts. Les geometries candidates sont nombreuses dans les premieres etapes de definition du produit et de design preliminaire, et des environnements d'optimisations multidisciplinaires sont developpes par les differentes industries aeronautiques. Differentes methodes impliquant differents niveaux de modelisations sont necessaires pour les differentes phases de developpement du projet. Lors des phases de definition et de design preliminaires, des methodes rapides sont necessaires afin d'etudier les candidats efficacement. Le developpement de methodes ameliorant la precision des methodes existantes tout en gardant un cout de calcul faible permet d'obtenir un niveau de fidelite plus eleve dans les premieres phases de developpement du projet et ainsi grandement diminuer les risques associes. Dans le domaine de l'aerodynamisme, les developpements des algorithmes de couplage visqueux/non visqueux permettent d'ameliorer les methodes de calcul lineaires non visqueuses en methodes non lineaires prenant en compte les effets visqueux. Ces methodes permettent ainsi de caracteriser l'ecoulement visqueux sur les configurations et predire entre autre les mecanismes de decrochage ou encore la position des ondes de chocs sur les surfaces portantes. Cette these se focalise sur le couplage entre une methode d'ecoulement potentiel tridimensionnelle et des donnees de section bidimensionnelles visqueuses. Les methodes existantes sont implementees et leurs limites identifiees. Une methode originale est ensuite developpee et validee. Les resultats sur une aile elliptique demontrent la capacite de l'algorithme a de grands angles d'attaques et dans la region post

  13. Considerations concerning the reliability of reactor safety equipment; Considerations sur la fiabilite des ensembles de securite de reacteurs

    Energy Technology Data Exchange (ETDEWEB)

    Furet, J; Guyot, Ch [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1967-07-01

    donne les resultats d'une analyse de fiabilite previsionnelle lorsque l'on utilise les elements fonctionnels en boitiers modulaires developpes industriellement en France. L'amelioration de cette fiabilite semble assez limitee par une augmentation de la redondance, par contre, on montre comment elle peut etre tres nettement amelioree par l'emploi de systemes de recherche automatique de pannes a des frequences tres differentes pour les sous-ensembles de mesure et les sous-ensembles logiques. Enfin, on montre sur des exemples l'incidence sur la fiabilite de la complexite et de l'emploi de technologies differentes dans les ensembles de securite de reacteurs. (auteurs)

  14. Development of a measuring and evaluation method for X-ray analysis of residual stresses in the surface region of polycrystalline materials; Entwicklung eines Mess- und Auswerteverfahrens zur roentgenographischen Analyse des Eigenspannungszustandes im Oberflaechenbereich vielkristalliner Werkstoffe

    Energy Technology Data Exchange (ETDEWEB)

    Genzel, C.

    2000-11-01

    The topic of the habilitation thesis is the development of an X-ray diffraction method for measurement and depth-resolved analysis of internal stresses in the surface region of polycrystalline materials. The method relies on the basic approach of varying {tau}, the penetration depth of the X-rays in the materials, by the scattering vector g{sub theta{psi}} via stepwise specimen rotation. Thus, depth profiles of the interlattice plane distances d(hkl) in the specimen system can be derived for given direction and inclination angles {theta} and {psi} of the scattering vector. This offers the possibility to identify individual components of the stress tensors of the basic equation of the X-ray diffraction analysis, and to perform separate analyses of those components. For calculation of the relevant internal stress distributions {sigma}{sub ij}({tau}) using the interlattice plane distance profiles, a self-consistent method is established which takes into account the high sensitivity of the derived internal stresses in relation to the interlattice plane distance d{sub 0}(hkl) in the stress-free crystal lattice. The evaluation yields results describing the depth profiles as well as the strain-free interlattice plane distance d{sub 0}(hkl), so that a quantitative analysis is possible of tri-axial internal stress states in the surface region of the materials. (orig./CB) [German] Den Gegenstand der vorliegenden Arbeit bildet die Entwicklung eines roentgenographischen Mess- und Auswerteverfahrens zur tiefenaufgeloesten Analyse des oberflaechennahen Eigenspannungszustandes in vielkristallinen Werkstoffen. Der Grundgedanke der Methode besteht darin, die Eindringtiefe {tau} der Roentgenstrahlung in den Werkstoff durch schrittweise Drehung der Probe um den Streuvektor g{sub {theta}}{sub {psi}} zu variieren. Damit koennen Tiefenprofile der Netzebenenabstaende d(hkl) fuer fest vorgegebene Azimut- und Neigungswinkel {theta} und {psi} des Streuvektors im Probensystem ermittelt

  15. Contribution to the study of the reaction p + {sup 11}B = 3 {alpha} by the coincidence method; Contribution a l'etude de la reaction p + {sup 11}B = 3 {alpha} par la methode des coincidences

    Energy Technology Data Exchange (ETDEWEB)

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

    1969-07-01

    We have studied the production mode of the 3 {alpha} system in the reaction p + {sup 11}B = {sup 12}C{sup *} = {alpha} + {sup 8}Be{sup *}; {sup 8}Be{sup *} = {alpha} + {alpha}. We have got some information for three different effects: the influence of the {sup 8}Be residual nucleus states = sequential decay; the influence of the {sup 12}C compound nucleus states = spin effect; an interference effect. We give a theoretical expression of the different spectra which take into account the observed phenomena. We have taken, as a parameter, the phase shift, between the waves associated with the detected particles, which produce the interference effect. The main characteristics of the experimental devices are : self supporting boron targets; cooled semiconductor detectors; multi-parametric system: for each nuclear event three parameters are recorded: the energies of the detected particles and the time of the detection; Recording system: the information are recorded on a magnetic tape and at the same time treated with an on line CAE 510 computer. The CAE 510 computer is used in delayed time to analyse the experimental data. (author) [French] Nous avons etudie le mecanisme de production du systeme 3 {alpha} dans la reaction: p + {sup 11}B = {sup 12}C{sup *} = {alpha} + {sup 8}Be{sup *}; {sup 8}Be{sup *} = {alpha} + {alpha}. Cette etude nous a permis de mettre en evidence trois effets de nature differente: l'effet des niveaux du noyau intermediaire {sup 8}Be reaction sequentielle; l'effet des niveaux du noyau compose {sup 12}C = effet de spin; -un effet d'interferences. Nous avons pu donner une expression theorique du spectre, rendant compte d'une facon satisfaisante des phenomenes observes. Pour cela nous avons considere le dephasage, entre les ondes associees aux particules detectees, qui produit les interferences, comme un parametre arbitraire. Du point de vue experimental les caracteristiques principales du materiel utilise sont les suivantes: utilisation de cibles de