WorldWideScience

Sample records for oprateurs sous elliptiques

  1. The theory of discrete barriers and its applications to linear boundary-value problems of the 'Dirichlet type'; Theorie des barrieres discretes et applications a des problemes lineaires elliptiques du ''type de dirichlet''

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

    1967-07-01

    This report gives a general presentation of barrier theory for finite difference operators, with its applications to some boundary value problems. (author) [French] Ce rapport est un expose synthetique de la theorie des barrieres pour les operateurs aux differences finies et ses applications a certaines classes de problemes lineaires elliptiques du 'type de Dirichlet'. (auteur)

  2. Le cerveau sous effet placebo

    Touzet , Claude

    2017-01-01

    International audience; Comment le fait de croire qu’on nous injecte de la morphine (alors qu’il s’agit de sérum physiologique) peut-il faire disparaître la douleur ? Investigation sur le cerveau sous placebo.

  3. SOUS LES PAVÉS: LA PLAGE!

    Clemmensen, Thomas Juel

    2017-01-01

    kunstnerbevægelse situationisterne brugte parolen sous les pavés: la plage! blev stranden associeret med det frie naturlige rum i kontrast til den brolagte gade, der repræsenterede samfundets undertrykkende orden. Men udtrykket kan samtidig minde os om geologiens allestedsnærværende karakter. Geologien findes lige...

  4. Clichy-sous-Bois (France) operation

    Dechamp, A

    1984-09-01

    The geothermal plant of Clichy-sous-Bois has been operating for 2 years and covers the needs of 3,400 equivalent-dwellings, including a sport-hall, 2 schools, the town-hall and 7 low-cost groups of flats. Geothermal energy covers 65% of the energy yearly global consumption for heating and sanitary hot water, i.e. 35,151 MWh. Thus, 3,195 TOE are saved each year. In December, 1979, the town of Clichy-sous-bois delegated their sponsorship to the Societe d'equipement et d'amenagement du territoire du departement de la Seine-Saint-Denis - SODETAT 93 for the realization of the geothermal operation. The production and injection wells were drilled between July and September, 1981. The Dogger aquifer was encountered at 1,800 m deep, with a temperature of 70,8/sup 0/C and an exploitation yield of 200m/sup 3//h. Surface works started in March 1982 and were completed in November of the same year. Apart from the geothermal power plant, the network comprises 11 exchange substations and a distribution network of 2,700 m long with 7,000 m of underground pipes. This plant is exploited by the Compagnie francaise d'exploitation thermique (COFRETH) within the framework of a farmout contract for 20 years, including: production, transportation and public distribution of geothermal heat all over the city of Clichy-sous-Bois.

  5. Dynamique des orbites fortement elliptiques

    Lion , Guillaume

    2013-01-01

    Most of the orbits of artificial satellites around the Earth have relatively low eccentricities. The calculation of their trajectories is very well under control, either by means of numerical methods when it comes to focus on accuracy and comparing observations, or either through analytical or semi-analytical theories to optimize the speed of calculations. This second category is used, in particular, for computing many long-term trajectories that could help to ensure the security and safety o...

  6. Radiculoplexopathie, anticorps anti Yo et cancer ovarien sous ...

    Les radiculo-plexopathies au cours des cancers sont le plus souvent d'origine métastatique. Leur origine dysimmune est rare. Nous rapportons un cas de radiculoplexopathie d'évolution favorable sous traitement immunomodulateur, survenue chez une patiente porteuse d'un carcinome ovarien bilatéral sous ...

  7. Palatability of sous vide processed chicken breast.

    Turner, B E; Larick, D K

    1996-08-01

    The influences of brine composition, internal temperature, heating rate, and storage periods up to 28 d on flavor, texture, and color of sous vide processed chicken breast were evaluated. Pectoralis major muscles containing water and sodium chloride, with or without sodium lactate, were browned and vacuum packaged. Sous vide processing was by fast or slow heating to an internal temperature of 77 or 94 C. Product was evaluated after 0, 14, and 28 d storage at 4 C. Quality was evaluated by gas chromatographic analyses of flavor volatiles, shear, color, and sensory panels. Incorporation of sodium lactate into brine did not influence oxidative stability (as measured by headspace gas chromatography) or sensory warmed-over flavor. Presence of sodium lactate did result in enhanced fresh roasted or meaty and saltiness sensory scores as well as a more yellow color. The more rapid heating rate decreased sulfur-containing compounds and did not influence other volatile concentrations. Products processed to 94 C were less juicy, less tender, and contained higher quantities of alcohols and hydrocarbons than those processed to 77 C. Storage resulted in a decline in fresh roasted or meaty flavor note and an increase in warmed-over flavor note and quantities of alcohols, aldehydes and ketones, hydrocarbons, and total headspace volatiles.

  8. Tambaqui (Colossoma macropomum sous vide: characterization and quality parameters

    Fabiane de Cássia Pontes Ramos

    2016-02-01

    Full Text Available The objective of this study was to evaluate the microbiological, physical and physico-chemical quality parameters of sous vide preparation of pen-reared tambaqui (Colossoma macropomum. To prepare the tambaqui sous vide, 200 g of fillet, 50 g of basil sauce (1:4 fish fillet:sauce ratio and 10 mL of 5% sodium lactate were used. The product was then vacuum-packaged, pasteurized at 65 ºC for 12.5 min and refrigerated. The presence of Salmonella spp., sulfite-reducing Clostridium and Listeria monocytogenes was not detected in the samples analyzed. The coliform count at 45 ºC and coagulase-positive staphylococci were below the limit (103 permitted by the law in vigor. Water retention capacity and chloride content analyses revealed that the tambaqui fillet differed significantly (P<0.05 from the sous vide because of the addition of basil sauce. The total volatile basic nitrogen (TVB-N and thiobarbituric acid reactive substances (TBARS content of the fillet and sous vide were below the limits established by the law, indicating good quality. The lightness (L* and yellow color (b* of the fillet and the sous vide did not differ significantly (P>0.05, but the red color (a* decreased in the sous vide, which is related to the addition of basil sauce. The chroma (C* and hue angle (ho differed significantly (P<0.05, and the fillet samples were lighter in color, whereas the sous vide was characterized by yellow color. The n-6/n-3 ratios found for the fillet and the sous vide are within the recommended values, which is important for human metabolism. The fillet and sous vide also had high calcium, zinc, magnesium and potassium concentrations. It is concluded that tambaqui sous vide is a good source of nutrients, rich in fatty acids and minerals essential for human health.

  9. Lipoblastome de la fosse sous temporale

    Najib, Jaafar; Aniba, Khalid; Laghmari, Mehdi; Lmejjati, Mohammed; Ghannane, Houssine; Benali, Said Ait; Ennadam, Hind; Mrabti, Hind; Idrissi, Nadia Cherif

    2014-01-01

    Le lipoblastome est une tumeur bénigne rare, formée d'adypocytes immatures associés à la présence d'une matrice myxoide, de septas fibreux, et d'une architecture lobulaire. Il survient généralement chez le nourrisson et l'enfant. Cette tumeur touche dans la majorité des cas les tissus sous-cutanés des extrémités et du tronc. Elle est extrèmement rare au niveau de la tète et du cou. Un total de moins de 100 cas a été rapporté précédemment dans la littérature. PMID:25918563

  10. The Sous Vide Revolution: Coming Full Circle and Beyond

    Hoeche, Ulrich

    2016-01-01

    For the purpose of this research, academic material and online sources were utilised to clarify the meaning of the key term sous vide. The Sous Vide Advisory Committee (1991) says ‘Sous Vide (also known as Cuisine en Papillote) is an interrupted catering system in which raw or par-cooked food is sealed into a vacuumised laminated plastic pouch or container, heat treated by controlled cooking, rapidly cooled and then reheated for service after a period of chilled storage’. According to Herb...

  11. La base sous-marine de Bordeaux, sous le béton la culture

    Mathieu Marsan

    2012-06-01

    Full Text Available Active à peine plus d’un an pendant l’Occupation, la base sous-marine de Bordeaux cristallise encore les souvenirs douloureux des heures sombres du Port de la Lune. Le bunker attire pourtant depuis les années 1960 des artistes, cinéastes, plasticiens et musiciens fascinés par l’esprit du lieu. Institutionnalisée au début des années 1990, la base sous-marine devient un espace dédié au nautisme avant d’être consacrée à l’art contemporain au début du XXIe siècle. Aujourd’hui au cœur du projet d’aménagement des bassins à flot du quartier de Bacalan, la base sous-marine questionne et intrigue ses visiteurs sur son passé, mais aussi – et surtout – sur son avenir.Build during the German occupation, the submarine base of Bordeaux active during hardly more than a year still crystallizes the painful memories of the dark hours of the « Port de la Lune ». Nevertheless, the bunker attracts artists, film-makers, visual artists and musicians fascinated by the spirit of the place since the 1960’s. Institutionalized at the beginning of 1990’s, the submarine base became a space dedicated to the yachting before contemporary art at the beginning of the XXIth century. Nowadays at the heart of the project of redevelopment of the wet docks in the urban area of Bacalan, the submarine base questions and intrigues its visitors on its past, but also – and especially – on its future.

  12. Fertilité des sols agricoles sous vigne et sous blé de la région de ...

    L'objectif de ce travail est l'évaluation agronomique de la qualité du sol sous vigne et sous blé dans la région Mohammedia-Benslimane au Maroc, à travers les indicateurs chimiques de la qualité du sol (pH, CE, CaCO3, Carbone organique total, Azote, Phosphore et Potassium). Les résultats de cette étude montrent que ...

  13. Deep geothermal energy: the Soultz-sous-Forets experience

    Genter, A.; Guenot, N.; Graff, J.J.

    2010-01-01

    This paper presents the mining exploitation project of the geothermal heat at Soultz-sous-Forets, located 50 km NE of Strasbourg (Bas Rhin, France). A geothermal power plant, inaugurated mid-2008, will commercialize its own power generation soon. This power plant is owned by a consortium of French-German industrialists through the European economical interest group for the mining exploitation of heat. The paper presents the geological characteristics of the hot dry rock geothermal reservoir, the deep geothermal wells, the hydraulic stimulation of the reservoir rock, the surface equipments of the power plants and the production pumps, the activities of the site in 2008 and 2009 and the perspectives of development of this energy source in France in the light of the Soultz-sous-Forets site experience. (J.S.)

  14. Plate forme L3 informatique sous application android

    BENDEDDOUCHE, Rida; BENAMARA, Mohammed El Amin

    2014-01-01

    Ce travail est présenté dans le cadre de notre projet de fin d’étude licence en informatique. Nous sommes actuellement dans une étape de transition de l’informatique fixe à l’informatique mobile. De jour en jour l’optimisation des smartphones ne cesse d’augmenter et cela grâce aux applications mobiles. Les smartphones utilisent plusieurs systèmes d’exploitation, une grande partie est sous Android. Les Smartphones et tablettes ont été conçus pour faciliter la vie quotidienne. En partant de ce ...

  15. Composes inter-halogenes sous pression: etude des transformations structurales dans le monobromure d'iode sous forme dense

    Bouchard, Alexandre

    La famille des composes halogenes et inter-halogenes representent des solides moleculaires adoptant des phases denses communes avec des solides moleculaires diatomiques comme l'azote et l'hydrogene. Parmi les transformations structurales et electroniques induites sous haute pression et observees dans ces solides, on note, entre autres, la dissociation moleculaire et la metallisation. De plus, l'etude des phases denses de l'iode a permis recemment l'observation d'une structure cristalline possedant une modulation dite incommensurable, c'est-a-dire une modulation possedant une periodicite differente de celle de la structure cristalline, jetant ainsi une lumiere nouvelle sur le processus de dissociation moleculaire dans les solides halogenes. Dans ce memoire, on propose d'etudier les changements structuraux dans monobromure d'iode (IBr), un compose inter-halogene possedant des proprietes structurales semblables a celles de deux composes halogenes, soit l'iode (I 2) et le brome (Br2) sous leur forme solide. Des experiences de diffraction des rayons X de poudres en utilisant un rayonnement synchrotron ont ete realisees a temperature ambiante sur l'IBr en variant la pression jusqu'aux environs de 60 GPa. La nature chimique particuliere du compose IBr a necessite la mise au point de techniques de chargement d'echantillon destinees a preserver l'integrite chimique de la substance utilisee. On rapporte egalement l'observation d'une phase de l'IBr presentant une modulation incommensurable. Les phases observees dans l'IBr permettent d'etablir des paralleles avec les phases denses rapportees dans I2 et Br2 par le biais d'un modele phenomenologique decrivant la sequence structurale des solides halogenes sous forme condensee.

  16. Le harcèlement organisationnel des relations sous emprise

    Guhel, Cécile

    2014-01-01

    Le lien entre harcèlement et emprise professionnelle est bien réel. Il est aussi puissant que destructeur. L'aide extérieure est importante mais la prise de conscience du sujet et sa mise à distance sont primordiales pour le retour à Soi. Un facteur de risque organisationnel est un facteur qui relève de l'organisation et qui comporte le risque ou la probabilité qu'un tel comportement abusif voie le jour et qu'il ait des effets négatifs. Un tel facteur peut également contribuer à la persistance ou à l'aggravation du comportement. En abordant la relation d'emprise sous l'éclairage de différentes théories psychologiques, cela vous permettra d'observer les mécanismes intrapsychiques conscients et inconscients qui sous-tendent les comportements de l'instigateur de la relation d'emprise d'une part, et de sa victime d'autre part. Enfin, à travers trois témoignages, de salariées en poste, vous découvrirez combien la parole sur le travail est importante dans la prise de conscience du processus de de...

  17. Changes in Meat Quality Characteristics of the Sous-vide Cooked Chicken Breast during Refrigerated Storage.

    Hong, Go-Eun; Kim, Ji-Han; Ahn, Su-Jin; Lee, Chi-Ho

    2015-01-01

    This study was performed to investigate the changes in meat quality characteristics of the sous vide cooked chicken breast during refrigerated storage at 4℃ for 14 d between before and after sous-vide cooking. Cooking loss and shear force were significantly increased, whereas expressible drip was significantly decreased along with reduction in the water holding capacity in both of two groups. Redness of meat juice was significantly (p<0.05) increased during storage, and considerably increased in the refrigerated samples after sous-vide cooked at the 7 to 10 d. The thiobarbituric acid reactive substances (TBARS) was significantly increased and was higher in the refrigerator stored chicken breast samples after sous-vide cooking. The volatile basic nitrogen (VBN) value was significantly increased in both groups, but the VBN value of the stored raw meat sample before sous-vide cooking was increased at an early storage, while the VBN value of the stored sample after sous-vide cooking was increased gradually in this study. Total viable counts and coliform counts were significantly decreased during storage, and coliforms were not detected after 7 d of storage in both groups. Salmonella spp. was not detected during the whole studied period. The outcome of this research can provide preliminary data that could be used to apply for further study of chicken breast using sous-vide cooking method that could be attractive to consumers.

  18. Pollution urbaine : la France sous le dôme

    Laurent, Eloi

    2017-01-01

    Un an exactement après avoir accueilli la COP21, Paris suffoquait début décembre sous un dôme de pollution, mais aussi Lyon, Villeurbanne, Marseille, Avignon, Rouen ou Grenoble. Airparif, qui a relevé un niveau de particules fines de 146 µg/m3 à Paris en moyenne pour le 1er décembre, précisait dans un communiqué qu’il s’agissait là d’un des pics hivernaux de pollution les plus sévères de ces dix dernières années, les précédents remontant à janvier 2009 et décembre 2007.

  19. Vacuum welding of metals; Soudage des metaux sous vide

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

    1958-07-01

    This new welding process has been developed by the Commissariat a l'Energie Atomique (CEA) in France. The edges of the work-pieces are melted by the impact of an electron beam produced by an electron gun. Welding is carried out in a vacuum of 10{sup -4} to 10{sup -8} mm of mercury. The welding machine consists, diagrammatically, of: a) a metal enclosure in which a vacuum is produced; b) a cathode for electron emission, a high-voltage generator for accelerating these electrons, a focusing device; c) a mechanical device for moving (rotating) the work-piece. Advantages of the process: 1) possible welding of highly oxidizable metals (e.g. zirconium); 2) fabrication of high-vacuum-sealed metal containers; 3) production of very deeply penetrated welds. Therefore, this new process is particularly advantageous for atomic power applications, the fabrication of electron tubes and, more generally, for all industries in which very special metals are used. (author) [French] Ce procede de soudage a ete recemment mis au point au Commissariat a l'Energie Atomique en France (CEA). Il consiste a utiliser, pour fondre les levres des pieces a souder, l'impact d'un faisceau d'electrons produit par un canon a electrons. Le soudage s'effectue sous un vide de 10{sup -4} a 10{sup -8} mm de mercure. La machine a souder se compose schematiquement: a) d'une enceinte metallique ou l'on fait le vide; b) d'une cathode emettant des electrons, d'un generateur H.T. permettant d'accelerer ces electrons d'un dispositif de focalisation; c) d'un dispositif mecanique permettant le deplacement (rotation) de la piece a souder. Avantages de ce procede: 1) possibilite de souder les metaux tres oxydables (exemple: zirconium); 2) realisation de 'containers' metalliques fermes sous vide pousse; 3) obtention de profondeurs de soudures considerables. Ce nouveau procede est donc particulierement interessant pour l ' energie atomique, la fabrication des tubes electroniques et, en general, toutes les industries

  20. Heat extraction from deep rocks at Soultz-sous-Forets

    Gerard, A.; Baumgaeriner, J.; Baria, R.

    1996-01-01

    A European coordinated research program for the study of hot-dry-rock systems is in progress at Soultz-sous-Forets (Alsace, France). The aim of this project is the extraction of heat from the granite batholiths distributed along the Rhine graben. The technique used involves important forced water circulations under relatively low-pressures using the natural geologic fractures network. The region concerned extends about 3000 km 2 under both the French and the German territories. The program started in 1987 with preliminary scientific investigations followed by a feasibility study. In December 1995, two deep wells, GPK1 (3600 m) and GPK2 (3900 m) were available and equipped for hydraulic testing. Temperatures encountered can reach 168 C at 3800 m with a geothermal gradient exceeding 3.5 C/100 m below 3600 m. The tests performed have shown that the hydraulic performances of these wells can be considerably improved using a simple well stimulation technique. (J.S.). 1 fig

  1. Al-Ḥudayyda sous occupation ottomane (1849-1918

    Patrice Chevalier

    2011-12-01

    Full Text Available Petit port de pêche situé sur les côtes de la mer Rouge, al-Ḥudayyda change progressivement de statut et de dimensions avec l’arrivée de l’armée ottomane en 1839. Al-Ḥudayyda se voit alors choisi comme l’un des points stratégiques (militaire et politique du dispositif colonial ottoman.Grâce aux différentes infrastructures mises en place par l’administration ottomane, mais aussi grâce à l’ouverture du canal de Suez en 1869, le village attire peu à peu une population multi-ethnique et cosmopolite venue y commercer ou simplement y trouver refuge, dans un contexte politique régional passablement agité. D’une centaine de Yéménites à l’origine, il compte 42 000 âmes à la veille de la première guerre mondiale.La cohabitation sous administration ottomane va-t-elle générer ou non des échanges ou emprunts entre les différentes communautés ? Les Ottomans vont-ils réussir à transcender les multiples appartenances identitaires au profit d’une appartenance citoyenne à l’empire, comme le prévoit leur ambitieux programme de réformes ? La ville d’al- Ḥudayyda sera-t-elle dotée d’une identité spécifique suffisamment forte pour que les individus appartenant aux différentes communautés présentes s’identifient à la ville ? Voilà quelques-unes des questions auxquelles cet article tente de répondre.

  2. Le sous-titrage : une pratique à la marge de la traduction

    Dumas, Louise

    2014-12-01

    Full Text Available Le sous-titre interlinguistique est un objet difficile à appréhender théoriquement. S'il permet d'aller d'une langue à une autre, il implique aussi un passage de l'écoute à la lecture et du cinéma à l'écriture. Le caractère interlinguistique est souvent mis en avant pour amener à considérer le sous-titrage comme une traduction. Sa complexité médiologique suggère toutefois qu'il est plus qu'une traduction. En même temps, les fortes contraintes (exigence de brièveté, de lisibilité, de cohérence avec l'image cinématographique auxquelles il est soumis font qu'il est moins qu'une traduction – moins exact, moins long, moins « équivalent » au texte original. Le présent travail se propose de réfléchir de manière théorique aux rapports entre sous-titrage et traduction. Pour ce faire, nous confronterons le sous-titrage aux concepts fondamentaux de la traductologie. Premièrement, le passage de l'oral à l'écrit opéré dans les sous-titres est intimement lié à la distinction traductologique entre traduction et interprétariat. Pour pouvoir condenser les dialogues, résumer leur contenu, le sous-titreur est amené à les interpréter, ce qui permet de souligner l'étroite parenté entre traduction, interprétariat et interprétation. Deuxièmement, les fortes contraintes auxquelles sont soumis les sous-titres invitent à s'interroger sur la notion d'équivalence qui se trouve normalement au principe de toute traduction. Toutes les théories traductologiques insistent sur le fait qu'une équivalence n'est jamais parfaite et que le traducteur privilégie certains niveaux d'équivalence : en poussant à l'extrême cette dynamique de sélection constitutive de l'équivalence, on peut considérer que les sous-titres sont équivalents aux dialogues. En tant que cas limite, le sous-titrage permet de tester les concepts fondamentaux de la traductologie et de définir leurs limites.

  3. Development of Pangasius steaks by improved sous-vide technology and its process optimization.

    Kumari, Namita; Singh, Chongtham Baru; Kumar, Raushan; Martin Xavier, K A; Lekshmi, Manjusha; Venkateshwarlu, Gudipati; Balange, Amjad K

    2016-11-01

    The present study embarked on the objective of optimizing improved sous - vide processing condition for development of ready-to-cook Pangasius steaks with extended shelf-life using response surface methodology. For the development of improved sous - vide cooked product, Pangasius steaks were treated with additional hurdles in various combinations for optimization. Based on the study, suitable combination of chitosan and spices was selected which enhanced antimicrobial and oxidative stability of the product. The Box-Behnken experimental design with 15 trials per model was adopted for designing the experiment to know the effect of independent variables, namely chitosan concentration (X 1 ), cooking time (X 2 ) and cooking temperature (X 3 ) on dependent variable i.e. TBARS value (Y 1 ). From RSM generated model, the optimum condition for sous - vide processing of Pangasius steaks were 1.08% chitosan concentration, 70.93 °C of cooking temperature and 16.48 min for cooking time and predicted minimum value of multiple response optimal condition was Y = 0.855 mg MDA/Kg of fish. The high correlation coefficient (R 2  = 0.975) between the model and the experimental data showed that the model was able to efficiently predict processing condition for development of sous - vide processed Pangasius steaks. This research may help the processing industries and Pangasius fish farmer as it provides an alternative low cost technology for the proper utilization of Pangasius .

  4. Une localisation exceptionnelle de la tuberculose vertébrale Mal de Pott sous-occipital

    Yahyaoui, Sana; Majdoub, Senda; Zaghouani, Houneida; Fradj, Hosni Ben; Bakir, Dejla; Bouajina, Elyes; Kraiem, Chakib

    2013-01-01

    Le mal de Pott est la forme la plus commune de la tuberculose osseuse touchant essentiellement le rachis dorso-lombaire. La localisation sous-occipitale reste exceptionnelle. Le diagnostic de cette entité est le plus souvent tardif ce qui expose à des complications graves. Les radiographies standard ne sont parlantes qu’à un stade tardif de la maladie, d'où l'intérêt de l'imagerie moderne notamment la tomodensitométrie (TDM) et l'imagerie par résonance magnétique (IRM) qui permettent un diagnostic précoce. Nous rapportons un nouveau cas de tuberculose sous-occipitale. Le diagnostic était posé sur l'imagerie en coupe et confirmé histologiquement à la biopsie transorale. Sont rappelés les aspects en imagerie de cette localisation particulière du mal de Pott. PMID:23819005

  5. Spécificités du sous-titrage pour enfants malentendants

    Comitre-Narvaez, Isabel

    2016-01-01

    Ce travail aborde la spécificité multisémiotique du texte audiovisuel qui est à l’origine de nombreux défis que le traducteur audiovisuel doit relever. Il explore les rapports intersémiotiques qui s’établissent entre le code verbal et le code visuel et se concentre sur les particularités du sous-titrage pour sourds et malentendants dans la “compensation” du déficit auditif, essentiellement son rapport spécifique à l’image. À cet égard, Gottlieb signale que le succès du sous-titrage dépend du ...

  6. Profil lipidique des personnes vivant avec le VIH sous antirétroviral ...

    Au regard des connaissances actuelles, aucune étude n'est disponible au Bénin sur le profil lipidique des personnes vivant avec le VIH. L'objectif de la présente étude est de décrire le profil lipidique des personnes vivant avec le VIH sous antirétroviral suivies au CHU-O/P de Porto-Novo. Il s'est agi d'une étude ...

  7. statut de la matiere organique des cambisols et des lixisols sous

    Administrateur

    L'étude vise à évaluer la matière organique des Cambisols et des Lixisols sous formations naturelles de longue durée en zone climatique nord-soudanienne et à établir, les relations entre ... sont supérieures à celles des sols des zones sahélienne et sud-soudanienne. ... globale a eu une corrélation positive avec le pH.

  8. Volatile compound profile of sous-vide cooked lamb loins at different temperature-time combinations.

    Roldán, Mar; Ruiz, Jorge; Del Pulgar, José Sánchez; Pérez-Palacios, Trinidad; Antequera, Teresa

    2015-02-01

    Lamb loins were subjected to sous-vide cooking at different combinations of temperature (60 and 80°C) and time (6 and 24h) to assess the effect on the volatile compound profile. Major chemical families in cooked samples were aliphatic hydrocarbons and aldehydes. The volatile compound profile in sous-vide cooked lamb loin was affected by the cooking temperature and time. Volatile compounds arising from lipid oxidation presented a high abundance in samples cooked at low or moderate cooking conditions (60°C for 6 and 24h, 80°C for 6h), while a more intense time and temperature combination (80°C for 24h) resulted on a higher concentration of volatile compounds arising from Strecker degradations of amino acids, as 2-methylpropanal and 3-methylbutanal. Therefore, sous-vide cooking at moderately high temperatures for long times would result in the formation of a stronger meaty flavor and roast notes in lamb meat. Copyright © 2014 Elsevier Ltd. All rights reserved.

  9. Microbiological and other characteristics of chicken breast meat following electron-beam and sous-vide treatments

    Shamsuzzaman, K.; Chuaqui-Offermanns, N.; Lucht, L.; McDougall, T.; Borsa, J.

    1992-01-01

    The combined effects of radiation and sous-vide treatment of chicken breast meat were investigated with respect to survival and growth of Listeria monocytogenes, shelf life, thiamine content, and sensory qualities. Chicken breasts were inoculated with L. monocytogenes 81-861 (10(5) CFU/G), vacuum-packed, irradiated with electron beam (EB) up to 2.9 kGy, and cooked to an internal temperature of 65.6 degrees C. Sous-vide treatment alone had marginal lethal effect on the L. monocytogenes; the residual inoculum reached 10(7) CFU/g after 8 weeks at 2 degrees C. However, after the combined treatments of sous-vide and EB at 2.9 kGy, the organism remained undetectable during the 8-week storage period. Parallel studies on uninoculated breast meat revealed that sous-vide samples had a shelf life of less than 6 weeks without EB treatment, whereas samples that were irradiated and then received sous-vide treatment had a shelf life of at least 8 weeks. There was a slight reduction in thiamine levels as a result of the EB treatment, but there was essentially no additional loss of thiamine due to the subsequent sous-vide treatment and storage at 2 degrees C. Electron-beam treatment had very little effect on the odor and flavor of the reheated samples. It was concluded that EB treatment combined with, sous-vide treatment can greatly enhance the microbial safety and shelf life of chicken breast meat

  10. Thermograms of the combined High Hydrostatic Pressure and Sous-vide treated Longissimus dorsi of pork

    Kenesei, Gy; Jónás, G.; Salamon, B.; Dalmadi, I.

    2017-10-01

    In this work, slices of Longissimus dorsi of pork was used as raw material to establish the effects of the sous-vide technology and the high hydrostatic pressure treatments (and their combinations) on meat. The state of the proteins in meat has a very important effect on several quality parameters of the product, such as weight loss, water holding capacity, organoleptic properties. Therefore it is important to follow and analyse the denaturation of the protein content during food processing. The samples were cooked sous-vide (60 °C, 5-480 minutes) or pressurized (100-600 MPa, 5 minutes, room temperature). Also two steps treatments were studied combining both technologies, applying high hydrostatic pressure treatment (300 or 600 MPa, 5 minutes, room temperature) after or previous to sous-vide cooking (60 °C, 30 minutes). The changes in the condition of meat proteins were followed by a differential scanning calorimeter. The DSC curves were analysed using the unit’s own software where denaturation heat was determined. Thermograms show through the change of the sample’s protein state the dissimilar effect of the treatments. Using the Polar Qualification System -previously proved to be effective with NIR measurements- the spectral information was reduced to a two dimensional polar co-ordinate system where each DSC curve is represented by a “quality point”. As a new experiment the applied PQS data reduction method compared to the traditional thermal analysis data processing gave us less information on the differences of our samples although the results are promising as we were able to detect the same trends and characteristics.

  11. Long-time water level observations at the HDR-testsite Soultz-sous-Forets

    Dornstaedter, J; Heinemann-Glutsch, B; Zaske, J [GTC-Kappelmeyer GmbH, Karlsruhe (Germany)

    1997-12-01

    Pressure or water level measurements have been performed by GTC in different wells at the geothermal testsite Soultz-sous-Forets for six years now. The water lever variations are mainly influenced by earth tides, barometric pressure variations, hydraulic testing and stimulation. The small scale variations are influenced by tidal and barometric forcing functions, the large scale variations by hydraulic testing and stimulation. By analyzing such measurements it is possible to get important information about the hydrualic connections between the boreholes, as well as aquifer parameters. (orig./AKF)

  12. Leuconostoc rapi sp. nov., isolated from sous-vide cooked rutabaga

    Lyhs, Ulrike; Snauwaert, I.; Pihlajaviita, S.

    2015-01-01

    A Gram-positive, ovoid lactic acid bacterium, strain LMG 27676T, was isolated from a spoiled sous-vide cooked rutabaga. 16S rRNA gene sequence analysis indicated that the novel strain belongs to the genus Leuconostoc, with Leuconostoc kimchi and Leuconostoc miyukkimchii as nearest neighbours (99.......1 and 98.8% 16S rRNA gene sequence similarity towards the type strain, respectively). Phylogenetic analysis of the 16S rRNA gene, multilocus sequence analysis of the pheS, rpoA and atpA genes, and biochemical and genotypic characteristics allowed to differentiate strain LMG 27676T from all established...

  13. Etude de la propagation sous critique dans les fibres de verre par relaxation de la charge

    R'Mili , M.; Godin , N.; Lamon , J.

    2011-01-01

    International audience; Plusieurs fibres inorganiques de type verre ou céramique (à base de carbure de silicium) sont très sensibles à la propagation sous critique de fissures, activée chimiquement ou thermiquement. Dans ce cas la rupture survient d'une façon prématurée à un niveau de contrainte relativement bas comparé à la contrainte de rupture. Cet article propose une approche statistique de la rupture en fatigue statique fondée sur l'analyse de la rupture des fibres dans une mèche sollici...

  14. Changes provoked by boiling, steaming and sous-vide cooking in the lipid and volatile profile of European sea bass.

    Nieva-Echevarría, Bárbara; Manzanos, María J; Goicoechea, Encarnación; Guillén, María D

    2017-09-01

    This study aims to shed light on the changes provoked by boiling, steaming and sous-vide cooking on the lipids and volatile profile of farmed and wild European sea bass meat. None of the cooking techniques provoked changes due to hydrolytic or oxidation processes detectable by 1 H NMR on sea bass lipids. The lipid profile of main and minor lipidic components was maintained after cooking. However, study by SPME-GC/MS evidenced that steaming and sous-vide cooking modified the volatile profile of sea bass meat, especially in farmed specimens. The compounds generated came from the occurrence, to a very small extent, of lipid and protein degradation. By contrast, boiling scarcely modified the initial characteristics of raw sea bass. Thus, from a sensory point of view and considering the odour-active compounds generated, steaming and sous-vide cooking provoked more noticeable changes than boiling, especially in farmed sea bass meat. Copyright © 2017. Published by Elsevier Ltd.

  15. Les effets potentiels du taping chez une population adulte souffrant d'un conflit sous-acromial

    Roch, Sylvie; Thétaz, Alain; Balthazard, Pierre

    2012-01-01

    Introduction : Le conflit sous-acromial est une pathologie fréquente qui touche une grande partie de la population. Quelques revues de la littérature recommandent une prise en charge spécifique, mais peu d’études proposent le taping comme adjuvant aux traitements préconisés. Ainsi ce travail de bachelor a pour objectif de déterminer les effets potentiels du taping chez une population adulte souffrant de conflit sous-acromial. Méthodologie : Notre recherche d’études s’est effectuée de janvier ...

  16. Vacuum brazing of metals (1961); Brassure sous vide des metaux (1961)

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

    1961-07-01

    We have studied brazing in vacuum aiming its application for the making of containers and apparatus meant for high vacuum (p < 10{sup -8} torr). We first define the wettability of a brazing alloy on a metal and we remind the influence of the various parameters which act on this wettability (nature of the solid, of the liquid, geometrical and physicochemical state of the surface, metallurgical reactions occurring at the interface, temperature, time). We give then the results of the tests carried out in order to determine the conditions of wettability in vacuum of some brazing alloys on metals which can be used for the above mentioned apparatus (stainless steel, aluminium, bronze, titanium, zirconium, kovar, nickel, copper). (author) [French] Nous avons etudie la brasure sous vide en vue de son application a la construction d'enceintes et apparelilage destines a l'obtention des vides eleves (p < 10{sup -8} torr). Nous definissons d'abord la mouillabilite d'une brasure sur un metal et nous rappelons l'influence des differents parametres qui agissent sur cette mouillabilite (nature du solide, du liquide, etat geometrique et physico-chimique de la surface, reactions metallurgiques a l'interface, temperature, temps). Nous donnons ensuite les resultats des essais effectues dans le but de determiner les conditions de mouillabilite sous vide de certaines brassures sur des metaux utilisables dans les constructions mentionnees ci-dessus (acier inoxydable, bronze d'aluminium, titane, zirconium, kovar, nickel, cuivre). (auteur)

  17. Thermal and radiation induced polymerisation of carbon sub-oxide; Polymerisation thermique et sous rayonnement du sous-oxyde de carbone

    Schmidt, Michel

    1964-03-15

    This research thesis addresses the study of the polymerisation of carbon sub-oxide (C{sub 3}O{sub 2}) in gaseous phase. As this work is related to other researches dealing with the reactions of the graphite-CO{sub 2} system which occur in graphite-moderated nuclear reactors, a first intention was to study the behaviour of C{sub 3}O{sub 2} when submitted to radiations. Preliminary tests showed that the most remarkable result of this action was the formation of a polymer. It was also noticed that the polymerisation of this gas was spontaneous however slower at room temperature. The research thus focused on this polymerisation, and on the formula of the obtained polymer. After some generalities, the author reports the preparation, purification and storage and conservation of the carbon sub-oxide. The next parts report the kinetic study of thermal polymerisation, the study of polymerisation under γ rays, the study of the obtained polymer by using visible, UV and infrared spectroscopy, electronic paramagnetic resonance, and semi-conductivity measurements [French] Le but de ce travail est l'etude de la polymerisation du sous-oxyde de carbone, C{sub 3}O{sub 2}, en phase gazeuse. Ce travail est en relation avec d'autres recherches concernant les reactions du systeme graphite-CO{sub 2} qui se produisent dans les reacteurs nucleaires de la filiere moderee au graphite. Notre premiere intention etait donc d'etudier le comportement de C{sub 3}O{sub 2} sous l'action des rayonnements. Or des essais preliminaires nous ont rapidement montre que le resultat le plus marquant de cette action etait l'obtention d'un polymere. On a egalement remarque que ce gaz polymerisait spontanement - quoique moins rapidement - a la temperature ambiante. Notre etude s'est donc circonscrite a cette polymerisation, avec ou sans rayonnements, ainsi qu'a son aboutissement: le polymere, dont nous avons tente d'eclaircir la formule. Au terme de cette etude, bien que certains points ne soient pas encore

  18. Effect of sous vide processing on physicochemical, ultrastructural, microbial and sensory changes in vacuum packaged chicken sausages.

    Naveena, B M; Khansole, Panjab S; Shashi Kumar, M; Krishnaiah, N; Kulkarni, Vinayak V; Deepak, S J

    2017-01-01

    The processing of sous vide chicken sausages was optimized under vacuum packaging condition and cooking at 100 ℃ for 30 min (SV30), 60 min (SV60) and 120 min (SV120) and compared with aerobically cooked control at 100 ℃ for 30 min. Sous vide processing of chicken sausages (SV30) produced higher (p emulsion ultra-structure due to SV30 processing relative to control sausages. Sous vide processing of chicken sausages enriched with rosemary diterpene phenols retained the freshness and quality up to 120 days during storage at 4 ± 1 ℃ relative to control sausages that were spoiled on 20th day. Lipid oxidation and microbial growth remained below the spoilage levels for all the SV-processed sausages throughout the storage and addition of rosemary diterpene mixture at 0.02% v/w reduced the microbial growth and improved (p < 0.05) the sensory attributes. Our results demonstrate that sous vide processing minimizes lipid oxidation and microbial growth of chicken sausages with improved product quality and shelf-life at 4 ± 1 ℃. © The Author(s) 2016.

  19. Guide pour la rédaction de cahiers des charges pour la sous-traitance en mécano-soudage

    Cheminat, Olivier

    2016-01-01

    Ce rapport est principalement dédié aux rédacteurs de cahiers des charges lors de sous-traitance en soudage. Le choix de faire sous-traiter une fabrication et le choix du sous-traitant revêtent une triple dimension technique, économique et stratégique. Un sous-traitant n'est pas un simple fournisseur ; il est un véritable partenaire technique pour le donneur d'ordre qui lui confie la réalisation d'un produit qu'il a lui-même conçu. La sous-traitance nécessite alors, outre un audit préalable du partenaire, un suivi en continu, à distance, et une communication entre le donneur d'ordre et le sous-traitant. Le cahier des charges est un des éléments de cette communication. C'est un outil essentiel, notamment lorsque le marché est soumis à des normes, imposées par contrat entre le donneur d'ordre et le sous-traitant. Ce présent document est un guide pour la rédaction du document de consultation, afin d'être le plus précis et exhaustif possible, mais il ne saurait être utilisé pour établi...

  20. Registration of vehicles at the Gex sous-préfecture: now by appointment only

    2016-01-01

    The Gex sous-préfecture has informed CERN that it has taken the following steps in order to reduce waiting times at its counters for the issue of carte grise vehicle registration certificates. As of 1 February 2016, you must book an appointment via the website http://www.rdv.ain.gouv.fr/ for all services relating to the registration of vehicles, in particular the:   change of the holder of a registration certificate, issue of a certificat de situation administrative (administrative status certificate required for the sale of a vehicle), change of marital status (or company name in the case of legal entities), change of address, change in the technical specification of the vehicle, corrections to registration certificates, equests for duplicates (loss or theft of registration certificates), registration of a diplomatic vehicle (CERN), registration of a new vehicle, registration of vehicles purchased tax-free in the Pays de Gex free zone (formerly TTW series), and import of vehicles (from ...

  1. Patrimonialiser les bases de sous-marins et le Mur de l’Atlantique

    Prelorenzo, Claude

    2014-01-01

    Le Mur de l’Atlantique court de la frontière espagnole jusqu’au nord de la Norvège. Au sein de ce dispositif sont installées cinq bases de sous-marins : Dunkerque, Saint-Nazaire, Lorient, La Rochelle et Bordeaux. Après une période de purgatoire, liée aux souvenirs trop frais des bombardements qu’ils ont attirés sur les villes, les édifices du mur sont entrés dans la sphère de la culture et du tourisme. Nous posons alors la question suivante : de quoi ces édifices portent-ils témoignage, et no...

  2. Raconter l’Histoire (sous la direction de Prstojevic A.

    Sophie Thiriar

    2011-10-01

    Full Text Available Sous le titre Raconter l’Histoire, Alexandre Prstojevic a réuni treize articles, faisant suite à deux colloques qui ont eu lieu à Paris en mai 2006 et à Montréal en octobre de la même année. Treize pointures du monde slave se sont intéressées pour l’occasion à la représentation littéraire et cinématographique de l’histoire – principalement celle de l’Europe centrale et orientale – après le spectacle mortifère des deux guerres mondiales. Suite aux multiples expériences déshumanisantes dont est...

  3. Scintigraphy of the Pericerebral Subarachnoidspaces; Scintigraphie des Espaces Sous-Arachnoidiens Pericerebraux

    Oberson, R.; Martini, T. [Institut Universitaire de Radiologie Medicale, Hopital Cantonal, Lausanne (Switzerland)

    1969-05-15

    -auricular shunt of the C.S.F. in cases of symptomatic hydrocephalus of traumatic or occult origin in adult or child patients. The study was based on an analysis of over 100 scintigrams of the pericerebral subarachnoid cavities. From this, the authors were gradually able to work out the normal and pathological symptomatology of this field, from the point of view of both cisternal morphology and fluid hydrodynamics. (author) [French] L'exploration des espaces sous-arachnoiediens pericerebraux par les radioisotopes (cisternographie radioisotopique ou 'RISA- cisternography' ) prend une place de plus en plus importante parmi les techniques neuroradioisotopiques de diagnostic. Elle fournit de precieux renseignements sur la permeabilite des espaces sous-arachnoiediens et sur la dynamique du liquide cephalo-rachidien (LCR). On doit actuellement la considerer comme indispensable et irremplacable dans le diagnostic de certaines affections neurologiques, tout comme la gamma-encephalographie et les techniques neuroradiologiques plus classiques (angiographie et pneumographie cerebrales). En effet, cet examen est seul a preciser l'aspect morphologique global des espaces sous-arachnoiediens pericerebraux; tout en renseignant sur la permeabilite des citernes pericerebrales et des sillons de la convexite, il fournit une image scintigraphique typique et symetrique, facile a observer, de face et de profil, des voies principales de circulation du LCR cisternal. L'image scintigraphique d'une citerne indique qu'elle est permeable et que l'espace sous-jacent l'est aussi. Du point de vue dynamique, la cisternographie radioisotopique, outre la demonstration par voie scintigraphique de la permeabilite des citernes, met en evidence le schema normal ou pathologique de la dynamique du LCR. Le schema normal de progression du LCR est actuellement bien etabli. Il est du plus haut interet de le connaitre afin de distinguer deja quelques syndromes pathologiques: la presence d'une fistule de LCR (la

  4. Les particules illocutoires, variable d’ajustement de la traduction sous-titrante au cinéma

    Ève Vayssière

    2010-12-01

    Full Text Available Die illokutiven Partikel fungieren als Anpassungsvariable, die beim Übersetzungsakt zur Untertitelung von Filmen entweder weggelassen werden oder erscheinen. Wenn sie einfach gelöscht werden, ergeben sich weder grammatikalische Störungen noch Informationsverlust. Das Auftauchen dieser Partikel in den deutschen Untertiteln zeigt jedoch, wie wichtig sie sind: Als Partikel der Oralität tragen sie zur Idiomatizität bei.Les particules illocutoires sont des variables d’ajustement lors de l’acte de traduction sous-titrante au cinéma, elles peuvent être supprimées sans que cela occasionne de dysfonctionnement grammatical et elles disparaissent lors de la traduction en français sans que cela occasionne une perte d’informations. Leur apparition dans les sous-titres allemands montre néanmoins leur importance : particules de l’oralité, elles sont vecteur d’« idiomaticité ».

  5. Patrimonialiser les bases de sous-marins et le Mur de l’Atlantique

    Claude Prelorenzo

    2011-06-01

    Full Text Available Le Mur de l’Atlantique court de la frontière espagnole jusqu’au nord de la Norvège. Au sein de ce dispositif sont installées cinq bases de sous-marins : Dunkerque, Saint-Nazaire, Lorient, La Rochelle et Bordeaux. Après une période de purgatoire, liée aux souvenirs trop frais des bombardements qu’ils ont attirés sur les villes, les édifices du mur sont entrés dans la sphère de la culture et du tourisme. Nous posons alors la question suivante : de quoi ces édifices portent-ils témoignage, et nous envisageons plusieurs aspects : leur évident modernisme qui les situe à un moment de l’histoire de l’architecture, leur hétérogénéité qui fait de ces bâtiments des sortes d’ovni, sans aucun rapport ni d’échelle ni de forme avec l’architecture civile, une technique d’enfouissement et de camouflage génératrice d’un nouveau paysage. Mais ces édifices peuvent-ils être exonérés de leur but guerrier ? Quel est le message de leur recyclage dans le culturel, le festif ou le commercial ? Deux bases de sous-marins sont plus particulièrement présentées, celle de Saint-Nazaire et celle de Lorient.The Atlantic Wall stretches from the Spanish border to northern Norway. Within this system there are five bases for submarines: Dunkirk, Saint-Nazaire, Lorient, La Rochelle and Bordeaux. After a period of purgatory, with the painful memories of the wartime air raids which destroyed the cities around the bases, the buildings which the Atlantic Wall comprises have now entered the spheres of culture and tourism. What do these buildings bear witness to? Their frank modernism puts them at a precise moment in the history of architecture. Their heterogeneity makes them like UFOs, without any relation of scale or form to civil architecture. Their specific techniques of dissimulation and camouflage created new landscapes. But can these buildings be freed from the memories of their original military purpose? What message is

  6. Effects of combined electron-beam irradiation and sous-vide treatments on microbiological and other qualities of chicken breast meat

    Shamsuzzaman, K.; Lucht, L.; Chuaqui-Offermanns, N.

    1994-01-01

    The microbiological safety, refrigeration shelf-life, and nutritional quality of chicken breast meat were investigated following combined electron-beam irradiation and cooking under vacuum (sous-vide). Chicken breast meat inoculated with 10 6 CFU/g of Listeria monocytogenes was irradiated with an electron beam at doses up to 3.1 kGy under vacuum in barrier bags, cooked in a boiling water bath for 3 min 45 s (previously determined to achieve an internal temperature of 71.1 o C), and stored at 8 o C for up to 5 weeks. Listeria was undetectable in samples treated with combined sous-vide and irradiation at 3.1 kGy, but the organism survived the sous-vide treatment without irradiation and multiplied during storage. A similar study, conducted with uninoculated chicken breast meat, revealed that the product which received both irradiation (3 kGy) and sous-vide treatment had a shelf-life of at least 8 weeks at 8 o C, whereas the unirradiated samples treated sous-vide spoiled in 16 days. Listeria was undetectable in combination treated samples, but some of the unirradiated sous-vide samples tested after long storage showed high levels of Listeria. Some loss of thiamine occurred with the combined treatments. (author)

  7. Production durable de légumes sous-utilisés en vue d'améliorer la ...

    Production durable de légumes sous-utilisés en vue d'améliorer la sécurité alimentaire en milieu ruralrity (Les légumes indigènes revêtent une importance capitale pour les femmes pauvres vivant en milieu rural, mais ont reçu, à ce jour, peu d'attention de la part des milieux de la recherche, du développement et des ...

  8. Integral modeling and financial impact of the geothermal situation and power plant at Soultz-sous-Forets

    Heidinger, Ph.

    2010-01-01

    The science about deep Enhanced Geothermal Systems (EGS) is still an emerging process and for further spreading economics is the key of the technology. To understand the financial situation, a program for economic evaluation was developed. This software (Euronaut) is completely modularized and considers all cash flows. Projects like an EGS are wrapped into tree-like structures. Based on the results which were gained at Soultz-sous-Forets, two configurations were designed. The first EGS configuration consists of a simplified two well (doublet) system where the dependencies of all components (mainly the reservoir, wells, pumps and the heat-to-power conversion unit) are physically and economically linked together. The realization of these dependencies and their complex interactions enable a sensitivity analysis of the borehole depth and reservoir depth, respectively. As a result, depth dependent effective costs and revenues of an EGS plant with the geohydrological characteristics of Soultz-sous-Forets are determined. As a future development, the second configuration will adapt the actual situation at Soultz-sous-Forets with the individual features of all four wells (GPK1 - GPK4). Then, this model can be used for all kinds of sensitivity analyses to clarify the impact of certain components or to optimize the operation scheme; e.g. the flow rates. (author)

  9. Improvement of microbiological safety of sous-vide meals by gamma radiation

    Farkas, J. E-mail: huto@omega.kee.hu; Polyak-Feher, K.; Andrassy, E.; Meszaros, L

    2002-03-01

    Experimental batches of smoked-cured pork in stewed beans sauce were inoculated with spores of psychrotrophic Bacillus cereus, more heat and radiation resistant than spores of non-proteolytic C. botulinum. After vacuum packaging, the meals were treated with combinations of pasteurizing heat treatments and gamma irradiation of 5 kGy. Prior and after treatments, and periodically during storage at 10 deg. C, total aerobic and total anerobic viable cell counts, and selectively, the viable cell counts of B. cereus and sulphite-reducing clostridia have been determined. The effects of the treatment order as well as addition of nisin to enhance the preservative efficiency of the physical treatments were also studied. Heat-sensitization of bacterial spores surviving irradiation occurred. The quality-friendly sous-vide cooking in combination with this medium dose gamma irradiation and/or nisin addition increased considerably the microbiological safety and the keeping quality of the meals studied. However, approx. 40% loss of thiamin content occurred as an effect of combination treatments, and adverse sensorial effects may also limit the feasible radiation doses or the usable concentrations of nisin.

  10. Improvement of microbiological safety of sous-vide meals by gamma radiation

    Farkas, J.; Polyak-Feher, K.; Andrassy, E.; Meszaros, L.

    2002-01-01

    Experimental batches of smoked-cured pork in stewed beans sauce were inoculated with spores of psychrotrophic Bacillus cereus, more heat and radiation resistant than spores of non-proteolytic C. botulinum. After vacuum packaging, the meals were treated with combinations of pasteurizing heat treatments and gamma irradiation of 5 kGy. Prior and after treatments, and periodically during storage at 10 deg. C, total aerobic and total anerobic viable cell counts, and selectively, the viable cell counts of B. cereus and sulphite-reducing clostridia have been determined. The effects of the treatment order as well as addition of nisin to enhance the preservative efficiency of the physical treatments were also studied. Heat-sensitization of bacterial spores surviving irradiation occurred. The quality-friendly sous-vide cooking in combination with this medium dose gamma irradiation and/or nisin addition increased considerably the microbiological safety and the keeping quality of the meals studied. However, approx. 40% loss of thiamin content occurred as an effect of combination treatments, and adverse sensorial effects may also limit the feasible radiation doses or the usable concentrations of nisin

  11. Shelf Life of Chicken Meat Balls Submitted to Sous Vide Treatment

    ÖP Can

    2015-06-01

    Full Text Available The objective of this study was to investigate the appropriate temperature for processing storage of chicken meatballs made of minced chicken meat with the sous vide method. The chicken meatballs were prepared and separated into four experimental groups according to the application of heat treatment (10 and 20 minutes and storage time (+2 and +10°C. Sensory, microbiological (total aerobic mesophilic bacteria, total psychrotrophs, lactic acidbacteria, Enterobacteriaceae, Clostridiumperfringens, Listeria spp., chemical (pH, thiobarbituric acid, color (L*, a*, b* values, and texture profile analyses were performed on meatball samples. Cl. perfringens and Listeria spp. were not detected in meatball samples during the storage period. Samples cooked at 10 minute and stored at +2°C the highest count of total aerobic mesophilic bacteria (p<0.05. For lipid oxidation, interaction was observed between cooking time and storage temperature, with higher TBARs values for samples stored at 10 °C, while cooking time and storage temperature showed no influence on the color and textural analysis parameters. For the treatments evaluated, cooking time x storage temperature seem affect more microbiological and chemical parameters than color and textural parameters of chicken meatballs.

  12. Fuel elements for pressurised-gas reactors; Elements combustibles des piles a gaz sous pression

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

    1958-07-01

    The design and fabrication of fuel elements for the first CO{sub 2} pressurized reactors have induced to investigate: various cladding materials, natural uranium base fuels, canning processes. The main analogical tests used in connection with the fuel element study are described. These various tests have enabled, among others, the fabrication of the fuel element for the EL2 reactor. Lastly, future solutions for electrical power producing reactors are foreseen. (author)Fren. [French] L'etude et la realisation d'elements combustibles pour les premieres piles a CO{sub 2} sous pression ont conduit a examiner: les divers materiaux de gaine, les combustibles a base d'uranium naturel, les modes de gainage. Les principaux essais analogiques ayant servi au cours de l'etude de la cartouche sont decrits. Ces divers essais ont notamment permis la realisation de la cartouche de la pile EL2. Enfin sont envisagees les solutions futures pour les piles productrices d'energie electrique. (auteur)

  13. Installation for analytic chemistry under irradiation; Installation de chimie analytique sous rayonnement

    Fradin, J; Azoeuf, P; Guillon, A [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1966-07-01

    An installation has been set up for carrying out manipulations and chemical analyses on radioactive products. It is completely remote-controlled and is of linear shape, 15 metres long; it is made up of three zones: - an active zone containing the apparatus, - a rear zone giving access to the active zone, - a forward zone independent of the two others and completely protected from which the remote-control of the apparatus is effected. The whole assembly has been designed so that each apparatus corresponding to an analytical technique is set up in a sealed enclosure. The sealed enclosures are interconnected by a conveyor. After three years operation, a critical review is now made of the installation. (authors) [French] L'installation a ete realisee pour effectuer des manipulations et des analyses chimiques sur des produits radioactifs. Elle est totalement telecommandee et se presente sous une forme lineaire de 15 metres de longueur et comporte trois zones: - une zone active d'appareillage, - une zone arriere d'intervention, - une zone avant independante des deux premieres et totalement protegee, ou s'operent les telecommandes de l'appareillage. L'ensemble a ete concu de facon a ce que chaque appareillage correspondant a une technique d'analyse soit implante dans une enceinte etanche. Les enceintes etanches sont reliees entre elles par un convoyeur. Apres trois annees de fonctionnement nous faisons le bilan et les critiques de l'installation. (auteurs)

  14. Les tuméfactions sous mandibulaires: à propos de 42 cas et revue de la literature

    Darouassi, Youssef; Mliha Touati, Mohamed; Chihani, Mehdi; Nadour, Karim; Ammar, Haddou; Bouaity, Brahim

    2014-01-01

    Les tuméfactions de la région sous mandibulaire sont une entité pathologique fréquente, caractérisées par un tableau clinique et une démarche diagnostique stéréotypée, et une unicité presque constante au plan chirurgical. Notre travail est une étude rétrospective sur une période de 5 an d'une série consécutive de 42 cas de tuméfactions sous mandibulaires qui ont été colligés au service d'oto-rhino-laryngologie et de chirurgie cervico-faciale de l'hôpital militaire Avicenne de Marrakech. L’âge moyen des patients était de 41 ans. Une prédominance masculine a été retrouvée. Le tableau clinique a été dominé par la tuméfaction sous mandibulaire. Tous les patients ont bénéficié d'une échographie cervicale. La tomodensitométrie cervicale a été réalisée chez 7 patients. La première étiologie était la sous maxillite chronique lithiasique dans 39,02% des cas. Le traitement était chirurgical dans tous les cas. En comparant les résultats avec ceux rapportés dans la littérature, nous allons discuter les différents aspects diagnostiques et thérapeutiques des étiologies les plus fréquentes. Les tuméfactions de la région sous mandibulaire sont fréquentes, nécessitant une démarche diagnostique rigoureuse et une prise en charge thérapeutique adaptée. PMID:25469195

  15. Sigand : une application SIG sous androïd (tablette de la gestion des chantiers

    CHAKIB SAFAR BATI

    2016-12-01

    Full Text Available L’introduction de données terrain pour les études environnementales ou de gestion de l’espace, régionales ou locales est une nécessité incontournable pour la validation des traitements et des interprétations mais aussi pour fournir des compléments d’informations aux divers travaux. Mais ce retour terrain est également de plus en plus demandé pour les gestionnaires de chantiers et de projets qui ont une exigence de contrôle ou de suivi et donc d’une information temps réel sur l’avancement des travaux, autrement pour introduire de nouvelles informations sur la base de données géoréférencées. Les avancées technologiques en matière de manipulation de l’information géographique (GPS, tablette graphique, téléphone portable, réalité augmentée permettent d’espérer la mise à dispositiondes professionnels, voire d’un plus large public, des outils adéquats pour de tels travaux. Actuellement, les outils d’élaboration, de gestion et d’exploitation des bases de données géographiques (solutions SIG ne sont pas encore complètement opérationnels en version « tablette » ; des applications telles que Qgis ou ArcGis sous Androïd attendent encore des développements. Nous présentons ici la première version d’une application SIG sous Androïd (disponible sur tablette pour la gestion en temps réel des chantiers qui permet de charger des couches vectorielles et de les mettre à jour sur le terrain en fonction de l’observation directe ; les couches (préalablement géoréférencées sont projetées sur des fonds cartographiques fournis par un serveur cartographique Google Maps (Route, Satellite, terrain; dans le cas d’absence de connexion internet, le fond cartographique est ramené d’un cache. Nous utilisons SpatialiteAndroïd pour le stockage et la manipulation des données géographiques. Le contrôleur de cartes Google Maps est employé pour afficher en mode cartographique les données stockées dans

  16. High pressure experimental water loop; Cellule experimentale a eau sous pression

    Grenon, M [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires; Terny, M [Societe Grenobloise d' Etudes et d' Applications Hydrauliques, 38 (France)

    1958-07-01

    A high pressure experimental water loop has been made for studying the detection and evolution of cladding failure in a pressurized reactor. The loop has been designed for a maximum temperature of 360 deg. C, a maximum of 160 kg/cm{sup 2} and flow rates up to 5 m{sup 3}/h. The entire loop consists of several parts: a main circuit with a canned rotor circulation pump, steam pressurizer, heating tubes, two hydro-cyclones (one de-gasser and one decanter) and one tubular heat exchanger; a continuous purification loop, connected in parallel, comprising pressure reducing valves and resin pots which also allow studies of the stability of resins under pressure, temperature and radiation; following the gas separator is a gas loop for studying the recombination of the radiolytic gases in the steam phase. The preceding circuits, as well as others, return to a low pressure storage circuit. The cold water of the low pressure storage flask is continuously reintroduced into the high pressure main circuit by means of a return pump at a maximum head of 160 kg /cm{sup 2}, and adjusted to the pressurizer level. This loop is also a testing bench for the tight high pressure apparatus. The circulating pump and the connecting flanges (Oak Ridge type) are water-tight. The feed pump and the pressure reducing valves are not; the un-tight ones have a system of leak recovery. To permanently check the tightness the circuit has been fitted with a leak detection system (similar to the HRT one). (author)Fren. [French] Une cellule experimentale a eau sous pression a ete realisee pour l'etude de l'evolution et de la detection de ruptures de gaines dans le cas d'un reacteur pressurise. Les performances de ce circuit sont: 350 deg. C maximum pour la temperature et 160 kg/cm{sup 2} maximum pour la pression, le debit pouvant atteindre 5 m{sup 3}/h. Le circuit complet est constitue de plusieurs parties: un circuit principal avec pompe de circulation a rotor immerge, preiseur a vapeur, tubes chaudieres

  17. Investigation of persistent Multiplets at the EGS reservoir of Soultz-Sous-Forêts, France

    Lengliné, O.; Cauchie, L.; Schmittbuhl, J.

    2017-12-01

    During the exploitation of geothermal reservoirs, abundant seismicity is generally observed, especially during phases of hydraulic stimulations. The induced seismicity at the Enhanced Geothermal System of Soultz-Sous-Forêts in France, has been thoroughly studied over the years of exploitation. The mechanism at its origin has been related to both fluid pressure increases during stimulation and aseismic creeping movements. The fluid-induced seismic events often exhibit a high degree of similarity and the mechanism at the origin of these repeated events is thought to be associated with slow slip process where asperities on the rupture zone act several times.To have a better understanding of the mechanisms associated with such events and on the damaged zones involved during the hydraulic stimulations, we investigate the behavior of the multiplets and their persistent nature over several water injection intervals. For this purpose, we analyzed large datasets recorded from a borehole seismic network for several water injection periods (1993, 2000). For each stimulation interval, thousands of events are recorded at depth. We detected the events using a STA/LTA approach and classified them into families of comparable waveforms using an approach based on cross-correlation analysis. Classification of the seismic events is then improved depending on their location within the multiplets. For this purpose, inter-event distances within multiplets are examined and determined from cross-correlation analysis between pairs of events. These distances are then compared to the source dimensions derived from the estimation of the corner frequencies estimation. The multiplets properties (location, events size) are then investigated within and over several hydraulic tests. Hopefully these steps will lead to increase the knowledge on the repetitive nature of these events and the investigation of their persistence will outline the heterogeneities of the structures (regional stress

  18. Faulting mechanisms and stress regime at the European HDR site of Soultz-sous-Forets, France

    Cuenot, Nicolas; Charlety, Jean; Haessler, Henri; Dorbath, Louis

    2006-01-01

    The state of stress and its implications for shear on fault planes during fluid injection are crucial issues for the HDR (Hot Dry Rock) or EGS (Enhanced or Engineered Geothermal System) concept. This is especially true for hydraulic stimulation experiments, aimed at enhancing the connectivity of a borehole to the natural fracture network, since they tend to induce the shearing of fractures, which is controlled by the local stress regime. During the 2000 and 2003 stimulation tests at Soultz-sous-Forets, France, about 10,000 microearthquakes were located with a surface seismological network. Hundreds of double-couple (DC) focal mechanisms were automatically determined from first-motion polarities using the FPFIT program [Reasenberg, P.A., Oppenheimer, D., 1985. FPFIT, FPPLOT and FPPAGE: Fortran computer programs for calculating and displaying earthquake fault-plane solutions. US Geological Survey Open-File Report 85-739, 25 pp.]. The majority of these mechanisms indicate normal-faulting movement with a more or less pronounced strike-slip component. Some quasi-pure strike-slip events also occurred, especially in the deeper part of the stimulated rock volume, at more than 5 km depth. Although we found a double-couple solution for all events, we tried to observe and quantify the proportion of the non-double-couple (NDC) component in the seismic moment tensor for several microseisms from the 2003 data. The study shows that the NDC is higher for the events in the vicinity of the injection well than for the events far from the well. We used the method of Rivera and Cisternas [Rivera, L., Cisternas, A., 1990. Stress tensor and fault-plane solutions for a population of earthquakes. Bull. Seismol. Soc. Am. 80, 600-614.] to perform the inversion of the deviatoric part of the stress tensor from P-wave polarities. This method was applied to different datasets from the 2000 test, taken from the shallower and deeper parts of the stimulated region. The results show a stable

  19. Faulting mechanisms and stress regime at the European HDR site of Soultz-sous-Forets, France

    Cuenot, Nicolas; Charlety, Jean; Haessler, Henri [Institut de Physique du Globe de Strasbourg, Ecole et Observatoire des Sciences de la Terre (IPGS-EOST), 5 rue Rene Descartes, 67084 Strasbourg Cedex (France); Dorbath, Louis [Institut de Physique du Globe de Strasbourg, Ecole et Observatoire des Sciences de la Terre (IPGS-EOST), 5 rue Rene Descartes, 67084 Strasbourg Cedex (France); Institut de Recherche pour le Developpement, Laboratoire des Mecanismes et Transferts en Geologie (IRD, LMTG), 14 Avenue Edouard Belin, 31400 Toulouse (France)

    2006-10-15

    The state of stress and its implications for shear on fault planes during fluid injection are crucial issues for the HDR (Hot Dry Rock) or EGS (Enhanced or Engineered Geothermal System) concept. This is especially true for hydraulic stimulation experiments, aimed at enhancing the connectivity of a borehole to the natural fracture network, since they tend to induce the shearing of fractures, which is controlled by the local stress regime. During the 2000 and 2003 stimulation tests at Soultz-sous-Forets, France, about 10,000 microearthquakes were located with a surface seismological network. Hundreds of double-couple (DC) focal mechanisms were automatically determined from first-motion polarities using the FPFIT program [Reasenberg, P.A., Oppenheimer, D., 1985. FPFIT, FPPLOT and FPPAGE: Fortran computer programs for calculating and displaying earthquake fault-plane solutions. US Geological Survey Open-File Report 85-739, 25 pp.]. The majority of these mechanisms indicate normal-faulting movement with a more or less pronounced strike-slip component. Some quasi-pure strike-slip events also occurred, especially in the deeper part of the stimulated rock volume, at more than 5 km depth. Although we found a double-couple solution for all events, we tried to observe and quantify the proportion of the non-double-couple (NDC) component in the seismic moment tensor for several microseisms from the 2003 data. The study shows that the NDC is higher for the events in the vicinity of the injection well than for the events far from the well. We used the method of Rivera and Cisternas [Rivera, L., Cisternas, A., 1990. Stress tensor and fault-plane solutions for a population of earthquakes. Bull. Seismol. Soc. Am. 80, 600-614.] to perform the inversion of the deviatoric part of the stress tensor from P-wave polarities. This method was applied to different datasets from the 2000 test, taken from the shallower and deeper parts of the stimulated region. The results show a stable

  20. Traduction audiovisuelle : quand le sous-titrage à destination des personnes sourdes et malentendantes se rencontrent dans le film "Le Prénom"

    Horii, Anaïk

    2015-01-01

    La traduction audiovisuelle est riche en méthodes de traduction : doublage, voice over, sur-titrage, audiodescription, etc. Ce mémoire se concentre sur la méthode du sous-titrage ainsi que sur celle du sous-titrage à destination des personnes sourdes et malentendantes. Le but était de comparer ces deux méthodes de traduction interlinguistique (dans les deux cas pour un public germanophone) en s'attardant sur les références culturelles ainsi que sur les langages populaire, familier et argotiqu...

  1. Influence of Sous Vide and water immersion processing on polyacetylene content and instrumental color of parsnip (Pastinaca sativa) disks.

    Rawson, Ashish; Koidis, Anastasios; Rai, Dilip K; Tuohy, Maria; Brunton, Nigel

    2010-07-14

    The effect of blanching (95 +/- 3 degrees C) followed by sous vide (SV) processing (90 degrees C for 10 min) on levels of two polyacetylenes in parsnip disks immediately after processing and during chill storage was studied and compared with the effect of water immersion (WI) processing (70 degrees C for 2 min.). Blanching had the greatest influence on the retention of polyacetylenes in sous vide processed parsnip disks resulting in significant decreases of 24.5 and 24% of falcarinol (1) and falcarindiol (2) respectively (p processing did not result in additional significant losses in polyacetylenes compared to blanched samples. Subsequent anaerobic storage of SV processed samples resulted in a significant decrease in 1 levels (p levels was observed (p > 0.05). 1 levels in WI processed samples were significantly higher than in SV samples (p processing with losses of up to 70% occurring after 5 days storage. 1 type polyacetylene undergoes degradation such as oxidation, dehydrogenation when thermally treated forming oxidized form of 1 type molecules, in this case falcarindione, dehydrofalcarinol, dehydrofalcarinone. Thermal processing had a significant effect on instrumental color of parsnip samples compared to minimally processed in both SV and WI processed samples resulting in parsnip disks becoming darker, yellower and browner following processing and storage.

  2. Determination of the Quality and Shelf Life of Sous Vide Cooked Turkey Cutlet Stored at 4 and 12ºC

    IT Akoğlu

    Full Text Available ABSTRACT The aim of this study was to determine the quality and shelf life of sous vide turkey cutlet stored at 4 and 12ºC. Samples were packaged under vacuum into polyamide-polypropylene pouches, cooked using sous vide technology (65ºC/40 min, chilled at 3ºC and stored at 4 and 12ºC for 5 weeks. Microbial (TMAB, lactic acid bacteria, Enterobacteriaceae, moulds and yeasts, Salmonella spp., L. monocytogenes, Cl. perfringens, physical-chemical (pH, water activity, TBARS, L*a*b* colour, texture profile analysis and shear force and sensory (appearance, colour, odour, flavour, juiciness, chewiness and acceptance parameters were determined. According to the results of mesophilic bacterial counts and sensory analysis, the shelf life of the sous vide turkey cutlet, cooked at 65ºC for 40 min, was determined as 28 days at 4ºC while 15 days at 12ºC. Salmonella spp., L. monocytogenes, Cl. perfringens were not detected in turkey cutlet samples during the storage period. It was detected that sous vide cooked provided convenient ready-to-eat foods and a long shelf life for turkey cutlet.

  3. Change in physical and chemical characteristics related to the binomial time-temperature used in sous pasteurization see Tambaqui (Colossoma macropomum

    H.C.A. Kato

    2016-02-01

    Full Text Available The goal of this study was to evaluate sous vide fish and assess the influence of time and temperature on the pasteurization process through quality parameters. The raw material (tambaqui fillets and the sous vide underwent physical, physicochemical, and microbiological analyses. A sauce was prepared containing soy sauce, water, horseradish and garlic flakes. The product's pasteurization parameters of time and temperature were defined according to a 22 central composite rotatable design (CCRD, and the dependent variables were water holding capacity (WHC and instrumental texture aiming at obtaining high WHC values for the product to maintain the desired juiciness. The microbiological analysis required by legislation have indicated that the fish fillets and sous vide were within de standard. The values of total coliforms found in the samples (fillets and sous vide analyzed were below the critical level of 10² CFU/g. The counts of sulphite-reducing clostridia and psychrotrophic and mesophilic bacteria on plates in the samples were <1x10 CFU/g. In conclusion, temperature was the most important factor in the pasteurization process, significantly contributing to the quality of the final product. The mathematical models proposed were considered predictive for each response.

  4. Influence of Citric Acid on the Pink Color and Characteristics of Sous Vide Processed Chicken Breasts During Chill Storage

    Lim, Ki-Won

    2015-01-01

    Chicken breast dipped with citric acid (CA) was treated by sous vide processing and stored in a refrigerated state for 0, 3, 6, 9, and 14 d. A non-dipped control group (CON) and three groups dipped in different concentrations of citric acid concentration were analyzed (0.5%, 0.5CIT; 2.0%, 2CIT and 5.0%, 5CIT; w/v). Cooking yield and moisture content increased due to the citric acid. While the redness of the juice and meat in all groups showed significant increase during storage, the redness of the citric acid groups was reduced compared to the control group (pacid reactive substances (TBARS) were generally lower in the citric acid-treated samples than in untreated ones, indicating extended shelf life of the cooked chicken breast dipped in citric acid solution. The shear force of the 2CIT and 5CIT groups was significantly lower (pcitric acid concentrations. PMID:26761885

  5. Effect of different temperature-time combinations on lipid and protein oxidation of sous-vide cooked lamb loins.

    Roldan, Mar; Antequera, Teresa; Armenteros, Monica; Ruiz, Jorge

    2014-04-15

    Forty-five lamb loins were subjected to sous-vide cooking at different combinations of temperature (60, 70 and 80 °C) and time (6, 12 and 24 h) to assess the effect on the oxidative stability of lipids and proteins. Heating induced both lipid and protein oxidation in lamb loins. Higher cooking temperature-time combinations increased conjugated dienes and decreased thiobarbituric reactive substances (TBARS) values and hexanal. Total protein carbonyls increased throughout time at all cooking temperatures considered, while α-aminoadipic (AAS) and γ-glutamic semialdehydes (GGS) increased when cooking at 60 °C but not at 80 °C. Links between the decrease in secondary compounds from lipid oxidation due to cooking at higher temperatures and for longer times with the increased levels of 3-methylbutanal and greater differences between total protein carbonyls and AAS plus GGS were hypothesised. Copyright © 2013 Elsevier Ltd. All rights reserved.

  6. Les images en géographie sous l’angledes humanités numériques

    Gaëlle Hallair

    2009-04-01

    Full Text Available L’article présente une méthodologie pour conserver, stocker, inventorier, archiver, numériser, indexer, valoriser et diffuser des archives géographiques sous l’angle des Digital humanities. L’article applique cette méthodologie aux images en géographie avant de présenter un projet de plate-forme documentaire concernant les plaques de verres du fonds Emmanuel de Martonne hébergées actuellement par l’UMR CNRS 8586 PRODIG.This article points out the methodology of Digital humanities to preserve, to stock, to make an inventory, to digitize, to index, to enhance the value und to spread geographical archives. It applies this methodology to geographical visual documents and presents a database project about photographic plates of the Emmanuel de Martonne’s collection localised in the research center PRODIG (UMR CNRS 8586.

  7. Lille, place financière intermédiaire sous la Révolution et l’Empire

    De Oliveira, Matthieu

    2011-01-01

    Dernière grande place négociante et financière avant la frontière septentrionale, Lille joue pleinement son rôle d’intermédiaire entre les marchés parisiens au Sud et belgo-hollandais au Nord sous la Révolution et l’Empire. La déclaration de guerre en 1792 puis la départementalisation des territoires conquis ne font que renforcer la position nodale des acteurs économiques et financiers de la place. Au premier rang d’entre eux, François Briansiaux mobilise efficacement son important réseau de ...

  8. Behaviour of uranium under irradiation; Comportement de l'uranium sous irradiation

    Adda, Y; Mustelier, J P; Quere, Y [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires; Commissariat a l' Energie Atomique, Fontenay-aux-Roses (France). Centre d' Etudes Nucleaires

    1964-07-01

    phase alloys (U Nb, U Mo) the size and distribution of the bubbles are greatly influenced by the existence of a polygonization lattice, formed before irradiation, inside the grains. During high temperature annealings the bubbles situated on the polygonization lattice grow much faster than those which are distributed inside the crystal. In the case of uranium the bubbles are either distributed at random, or grouped in flat accumulations which can give rise to transgranular cracks, according to the state of the metal and the irradiation temperature. At high temperature an intergranular de-cohesion is also observed. (authors) [French] On expose les principaux resultats obtenus dans l'etude de la formation des defauts introduits dans l'uranium par la fission a basse temperature. Par irradiation a 20 K on a pu evaluer le nombre de paires de Frenkel produites par une fission. L'analyse des courbes de variation de resistivite electrique a permis de preciser l'etendue des pointes de deplacement (deplacement Spike) et le mecanisme de la creation des defauts dus a la fission. Des irradiations a 77 K ont apporte des precisions supplementaires et indiquent un comportement different de l'uranium recristallise et ecroui. On a etudie la diffusion des gaz rares a partir d'alliages metal-gaz rare obtenus par decharge electrique et d'echantillons d'uranium irradie. Le degagement des gaz rares sous vide n'est controle par un processus de diffusion simple que dans le cas ou la teneur en gaz rare est tres faible (U tres faiblement irradie). Par contre quand la teneur en gaz rare est plus forte (echantillons prepares par decharge electrique) le degagement du gaz se produit par formation, croissance et coalescence de bulles; le coefficient de diffusion apparent est alors tres different du coefficient vrai et ne peut etre utilise dans les calculs de gonflement. Dans le cas d'un processus de diffusion simple on a etudie les differents facteurs qui regissent le phenomene. On a montre en

  9. Utilisation des sous-produits agroalimentaires dans l’alimentation des poissons d’élevage en Côte d’Ivoire

    Kimou Nestor B.

    2016-03-01

    Full Text Available Cette étude évalue l’impact de l’utilisation des sous-produits agroalimentaires dans l’alimentation des poissons d’élevage en Côte d’Ivoire. Une enquête a été réalisée en 2013 dans quinze principales zones piscicoles sur les caractéristiques technico-économiques des fermes, le profil socio-économique des promoteurs et les pratiques aquacoles, particulièrement l’alimentation des poissons. Les résultats révèlent que 71 % des pisciculteurs enquêtés utilisent des sous-produits agricoles durant au moins un stade de production. Parmi eux, 53 % utilisent exclusivement des sous-produits. Le son de riz (52 % et le mélange de sons de riz et de maïs (28 % sont les plus utilisés. Les prix moyens de ces sous-produits varient entre 20 et 105 FCFA/kg. Oreochromis niloticus et Heterotis niloticus sont les principales espèces élevées en polyculture sur les fermes. Les sous-produits sont utilisés en système semi-intensif, extensif et en rizipisciculture, en majorité en zone rurale. Les pisciculteurs sont pour la plupart des agriculteurs, âgés de plus de 40 ans. Les taux d’utilisation des sous-produits sont plus élevés dans les régions de l’Ouest, du Centre-Ouest et du Sud-Ouest de la Côte d’Ivoire, par rapport à celles du Sud et de l’Est. Les rendements des fermes sont relativement faibles (544 à 2445 kg/ha/an, avec des gains moyens quotidiens de 0,87 et 9,97 g/j pour le tilapia et l’heterotis respectivement. L’analyse des stratégies des acteurs suggère la nécessité de définir des mécanismes d’accompagnement et de financement de la pisciculture, afin que ces acteurs puissent améliorer les formulations alimentaires à partir des matières premières locales et accessibles.

  10. Effect of the cooking method (grilling, roasting, frying and sous-vide) on the oxidation of thiols, tryptophan, alkaline amino acids and protein cross-linking in jerky chicken

    Silva, Fábio A. P.; Ferreira, Valquíria C. S.; Madruga, Marta S.; Estévez, Mario

    2016-01-01

    Broiler breast (pectoralis major) meat was submitted to salting with NaCl + NaNO3 followed by a drying process to produce jerky-type chicken. The final product (raw broiler charqui) was desalted and then cooked using grilled, roasted, fried and sous-vide techniques. Sous-vide cooked samples showed lowest results of moisture loss compared to roasted and fried ones. Fatty acid profile suffered minor changes after cooking of broiler charqui. Regarding to protein oxidation, tryptophan fluorescenc...

  11. PH measurement under pressure and at high temperatures; Mesure du pH sous pression et a temperature elevee

    Fournie, R [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires; Le Peintre, M; Mahieu, C [Centre National de la Recherche Scientifique (CNRS), 91 - Gif-sur-Yvette (France)

    1961-07-01

    In the first part the development and operation of a glass electrode under pressure at room temperature is described. The pressure equilibrium between the inside and outside of the glass membrane several centimetres thick is obtained instantaneously by means of a siphon. The use of a silicone oil as electrical insulator makes possible the working of the glass electrode with the siphon at high pressures (100 kg/cm{sup 2}). In the second part, we determined the pH of various buffer solutions up to 250 deg. C using a cell of our design having two hydrogen electrodes. The values thus obtained for the buffer solutions make it possible to verify and calibrate the pH electrodes independently of the oxido-reduction potential of the medium. In the third part we give the results obtained up to 200 deg. C with the glass electrodes developed in conjunction with the Societe St Gobain. (author) [French] Dans une premiere partie, nous exposons la mise au point et le fonctionnement d'une electrode en verre sous pression a la temperature ordinaire. L'equilibrage instantane de la pression a l'interieur et a l'exterieur de la membrane en verre de quelques diziemes de millimetres d'epaisseur s'effectue par l'intermediaire d'un siphon. L'emploi d'une huile de silicone comme isolant electrique a permis le fonctionnement de l'electrode en verre a siphon sous haute pression (1000 kg/cm{sup 2}). Dans une deuxieme partie, nous avons determine jusqu'a 250 deg. C les valeurs du pH des diverses solutions tampons avec une cellule de notre conception a deux electrodes d'hydrogene. Les valeurs des solutions tampons ainsi obtenues permettent de verifier et d'etalonner les electrodes a pH independantes du potentiel d'oxydo-reduction du milieu. Dans une troisieme partie, nous relatons les resultats obtenus jusqu'a 200 deg. C avec les electrodes en verre mis au point en collaboration avec la Societe Saint-Gobain. (auteur)

  12. Measurements for uranium-light water subcritical assembly; Mesures pour ensemble sous-critique uranium-eau legere d'enseignement

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

    1964-07-01

    The aim of this report is to determine the matter Laplacian of a subcritical assembly, done for educational purposes, using natural uranium combustible and light water for the moderator and the reflector. (M.B.) [French] L'objet de ce rapport est la determination du Laplacien matiere d'un reseau sous-critique, destine a l'enseignement, utilisant comme combustible l'uranium naturel et comme moderateur et reflecteur l'eau naturelle. (M.B.)

  13. Microfracture pattern compared to core-scale fractures in the borehole of Soultz-sous-Forets granite, Rhine graben, France

    Dezayes, C.; Villemin, T. [Universite de Savoie (France). Laboratoire de Geodynamique des Chaines Alpines, UPRES-A CNRS 5025; Pecher, A. [Universite Joseph Fourier, Grenoble (France). Laboratoire de Geodynamique des Chaines Alpines, UPRES-A CNRS 5025

    2000-07-01

    Microfractures appearing in thin section as fluid inclusion trails in quartz crystals were studied in four core samples of Soultz-sous-Forets granite. Their orientations in four series of three mutually perpendicular thin sections were estimated using a previously described apparent dip method and a new method involving measurements of strike and apparent dips. Three samples display three microfracture sets and one sample displays two sets. In all samples, one set is nearly vertical and strikes N-S. In two samples, one and two sets are nearly vertical and strike E-W. In two samples, two sets strike NW-SE: one is vertical, the other dips gently to the NE (or SW). Comparing microfracture and mesofractures sets in the same cores shows that (1) the N-S microfacture set is always dominant at both scales and (2) all other microfracture sets have no mesoscopic counterpart. The N-S microfracture sets could have been created during E-W extension of earliest Cenozoic age (Rhine Graben rifting). Differences between the two scales are explained by a {sigma}{sub 1}/{sigma}{sub 2} switching which occurred at the crystal scale and generated mutually perpendicular cracks.

  14. Studies and support for the EGS reservoirs at Soultz-sous-Forets. April 2004 - May 2009. Final report

    Portier, S.; Vuataz, F.-D. [Centre de Recherche en Geothermie (CREGE), Neuchatel (Switzerland)

    2009-08-15

    This comprehensive final report for the Swiss Federal Office of Energy (SFOE) takes a look at the activities carried out during the period from April 2004 up to May 2009 at Soultz-sous-Forets, France, in connection with the enhanced geothermal systems (EGS) at that location. The report describes the work performed by the Swiss EGS Research and Development group involved in the Soultz project. The principal target set was to install and operate a power plant, enabling the deep reservoir/heat exchanger to be operated, evaluated and improved under realistic conditions. The Swiss contributors have been participating in several work packages: Short and long term tests and medium-term tests of the three-well reservoir/heat exchanger system, development and up-scaling, technical and economic design of larger, industrial, EGS units and the development of stimulation methodology for EGS. The exchange of findings obtained during this project phase is discussed, as is the state-of-the-art of EGS stimulation methods, the interpretation of logging data. Also, seismic /-hydraulic factors, the evaluation of the production/injection performance of the boreholes and reservoir development strategies are discussed as are the modelling of geochemical impact of forced fluid circulation in the deep geothermal reservoir and the results of chemical stimulation tests performed on site.

  15. Efficacy of Combined Sous Vide-Microwave Cooking for Foodborne Pathogen Inactivation in Ready-to-Eat Chicory Stems.

    Renna, Massimiliano; Gonnella, Maria; de Candia, Silvia; Serio, Francesco; Baruzzi, Federico

    2017-07-01

    There is a variety of different food processing methods, which can be used to prepare ready-to-eat foods. However, the need to preserve the freshness and nutritional qualities leads to the application of mild technologies which may be insufficient to inactivate microbial pathogens. In this work, fresh chicory stems were packed under a vacuum in films, which were transparent to microwaves. These were then exposed to microwaves for different periods of time. The application of sous vide microwave cooking (SV-MW, 900 W, 2450 MHz), controlled naturally occurring mesophilic aerobic bacteria, yeasts and molds for up to 30 d when vacuum-packed vegetables were stored at 4 °C. In addition, the process lethality of the SV-MW 90 s cooking was experimentally validated. This treatment led to 6.07 ± 0.7 and 4.92 ± 0.65 log cfu/g reduction of Escherichia coli and Listeria monocytogenes inoculated over the chicory stems (100 g), respectively. With an initial load of 9 log cfu/g for both pathogens, less than 10 cfu/g of surviving cells were found after 90 s cooking. This shows that short-time microwave cooking can be used to effectively pasteurize vacuum-packed chicory stems, achieving >5 log cfu/g reduction of E. coli and L. monocytogenes. © 2017 Institute of Food Technologists®.

  16. Effets Seebeck et Nernst dans les cuprates: Etude de la reconstruction de la surface de Fermi sous champ magnetique intense

    Laliberte, Francis

    2010-06-01

    Ce memoire presente des mesures de transport thermoelectrique, les effets Seebeck et Nernst, dans une serie d'echantillons de supraconducteurs a haute temperature critique. Des resultats obtenus recemment au Laboratoire National des Champs Magnetiques Intenses a Grenoble sur La1.7Eu0.2Sr0.1 CuO4, La1.675Eu0.2Sr0.125CuO 4, La1.64Eu0.2Sr0.16CuO4, La1.74Eu0.1Sr0.16CuO4 et La 1.4Nd0.4Sr0.2CuO4 sont analyses. Une attention particuliere est accordee aux equations de la theorie semi-classique du transport et leur validite est verifiee. La procedure experimentale et les materiaux utilises pour concevoir les montages de mesures sont expliques en detail. Enfin, un chapitre est dedie a l'explication et l'interpretation des resultats de transport thermoelectrique sur YBa2Cu3O6+delta publies au cours de l'hiver 2010 dans les revues Nature et Physical Review Letters. Les donnees d'effet Seebeck dans les echantillons de La 1.8-x,Eu0.2SrxCuO 4, ou un changement de signe est observe, permettent de conclure a la presence d'une poche d'electrons dans la surface de Fermi qui domine le transport a basse temperature dans la region sous-dopee du diagramme de phase. Cette conclusion est similaire a celle obtenue par des mesures d'effet Hall dans YBa 2Cu3O6+delta et elle cadre bien dans un scenario de reconstruction de la surface de Fermi. Les donnees d'effet Nernst recueillies indiquent que la contribution des fluctuations supraconductrices est limitee a un modeste intervalle de temperature au-dessus de la temperature critique.

  17. Oxidation of steel heated in CO{sub 2} medium under pressure; Oxydation d'un acier ordinaire chauffe dans le gaz carbonique sous pression

    Darras, R.; Leclercq, D.; Bunard, C. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1958-07-01

    Behaviour of low-alloyed steels heated in CO{sub 2} medium under pressure is reported. Tests are carried out in the range of erature reached in the CO{sub 2} cooled reactors (vessel, thermal shield, pipes). The observed weight increases are small, even after more than a thousand hours of heating at 350 deg. C, but oxidation curve looks like progressing linearly. Furthermore, the oxide formed under a pressure of 15 kg/cm{sup 2} is undoubtedly more compact and adherent than the one formed under a pressure of 1 kg/cm{sup 2}. Finally, for practical use, CO{sub 2} steel pipes surface has to be sand blast and pickled. A following phosphatizing protects it from atmospheric corrosion during assembling, but these treatments have no influence on the behaviour of these steels heated in CO{sub 2}. (author)Fren. [French] On etudie le comportement d'aciers au carbone faiblement allies, chauffes dans le gaz carbonique sous pression, aux temperatures atteintes dans les reacteurs refroidis par ce gaz (caisson, bouclier thermique, canalisations). Les augmentations de poids observees sont faibles, meme apres plus de 1000 heures de chauffage a 350 deg. C, mais l'oxydation semble se poursuivre lineairement. De plus, l'oxyde forme dans le gaz carbonique sous pression de 15 kg/cm{sup 2} est nettement plus compact et adherent que celui forme sous pression atmospherique de gaz carbonique. Enfin, dans la pratique, les surfaces d'acier du circuit de gaz carbonique sont necessairement sablees ou decapees; une phosphatation ulterieure le protege de la corrosion atmospherique pendant le montage. Ces traitements sont sans influence sur le comportement de ces aciers dans le gaz carbonique a chaud. (auteur)

  18. Oxidation of steel heated in CO{sub 2} medium under pressure; Oxydation d'un acier ordinaire chauffe dans le gaz carbonique sous pression

    Darras, R; Leclercq, D; Bunard, C [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1958-07-01

    Behaviour of low-alloyed steels heated in CO{sub 2} medium under pressure is reported. Tests are carried out in the range of erature reached in the CO{sub 2} cooled reactors (vessel, thermal shield, pipes). The observed weight increases are small, even after more than a thousand hours of heating at 350 deg. C, but oxidation curve looks like progressing linearly. Furthermore, the oxide formed under a pressure of 15 kg/cm{sup 2} is undoubtedly more compact and adherent than the one formed under a pressure of 1 kg/cm{sup 2}. Finally, for practical use, CO{sub 2} steel pipes surface has to be sand blast and pickled. A following phosphatizing protects it from atmospheric corrosion during assembling, but these treatments have no influence on the behaviour of these steels heated in CO{sub 2}. (author)Fren. [French] On etudie le comportement d'aciers au carbone faiblement allies, chauffes dans le gaz carbonique sous pression, aux temperatures atteintes dans les reacteurs refroidis par ce gaz (caisson, bouclier thermique, canalisations). Les augmentations de poids observees sont faibles, meme apres plus de 1000 heures de chauffage a 350 deg. C, mais l'oxydation semble se poursuivre lineairement. De plus, l'oxyde forme dans le gaz carbonique sous pression de 15 kg/cm{sup 2} est nettement plus compact et adherent que celui forme sous pression atmospherique de gaz carbonique. Enfin, dans la pratique, les surfaces d'acier du circuit de gaz carbonique sont necessairement sablees ou decapees; une phosphatation ulterieure le protege de la corrosion atmospherique pendant le montage. Ces traitements sont sans influence sur le comportement de ces aciers dans le gaz carbonique a chaud. (auteur)

  19. Brigitte SIMONOT et Gabriel GALLEZOT (2009) (dir.), L’entonnoir : Google sous la loupe des sciences de l’information et de la communication

    Bonaccorsi, Julia

    2013-01-01

    Ce titre annonce d’emblée une posture critique et, plus largement, une promesse de dévoilement. L’approche communicationnelle, affirmée dès le sous-titre, saisit Google comme un objet de recherche à construire à distance des discours promotionnels ou pamphlétaires. La recherche collective prend appui sur une perspective sociotechnique, mais également sociopolitique du moteur de recherche et de ses usages, pour interroger la production de valeurs par la société Google. Le moteur est scruté au ...

  20. Une introduction aux problèmes inverses elliptiques et paraboliques

    Choulli, Mourad

    2009-01-01

    This book is devoted to an introduction of elliptic and parabolic inverse problems. Our goal is to present some recent methods for establishing uniqueness and stability results. We study some classical elliptic inverse problems: inverse conductivity problem, detection of corrosion or cracks and inverse spectral problems. Among the parabolic inverse problems we consider the classic problem of finding an initial distribution of heat and the location of sources. We hope that this book will interest all those who want to learn the mathematical analysis of inverse problems.

  1. Effect of the cooking method (grilling, roasting, frying and sous-vide) on the oxidation of thiols, tryptophan, alkaline amino acids and protein cross-linking in jerky chicken.

    Silva, Fábio A P; Ferreira, Valquíria C S; Madruga, Marta S; Estévez, Mario

    2016-08-01

    Broiler breast ( pectoralis major ) meat was submitted to salting with NaCl + NaNO 3 followed by a drying process to produce jerky-type chicken. The final product (raw broiler charqui) was desalted and then cooked using grilled, roasted, fried and sous-vide techniques. Sous-vide cooked samples showed lowest results of moisture loss compared to roasted and fried ones. Fatty acid profile suffered minor changes after cooking of broiler charqui. Regarding to protein oxidation, tryptophan fluorescence, protein carbonylation and disulphide bonds formation of chicken charqui were affected by cooking temperature while free thiol groups, Schiff base formation and hardness were mostly impacted by the length of cooking. Instrumental color of broiler charqui was affected by the type of cooking, being closely related with Maillard products formation. In conclusion, sous-vide technique seems to be the most advantageous cooking method to obtain high-quality ready-to-eat chicken charqui.

  2. Physicochemical and microbiological changes during the refrigerated storage of lamb loins sous-vide cooked at different combinations of time and temperature.

    Roldán, Mar; Antequera, Teresa; Hernández, Alejandro; Ruiz, Jorge

    2015-10-01

    This study aimed to determine the influence of cooking temperature (either 60 ℃ or 80 ℃) and time (6 h or 24 h) on the physicochemical (weight loss, moisture content, instrumental color, instrumental texture, lipid and protein oxidation) and microbiological changes underwent by sous-vide cooked lamb loins during refrigerated storage for 30 days. There was a slight trend to decreasing weight losses in some of the cooking treatments, but only in samples cooked at 60 ℃ for 6 h it was paralleled with an increase in moisture content. The only noteworthy oxidative change was a marked decrease in conjugated dienes after two weeks of storage in samples cooked at 80 ℃ for 24 h. Neither instrumental texture nor color showed noticeable variations during the storage. Microbial population remained quite low during the whole refrigerated storage. Overall, most of the studied parameters showed only scarce changes throughout 30 days of refrigerated storage that most likely would not influence the quality of sous-vide cooked loin lambs. © The Author(s) 2014.

  3. Oxidation of ordinary steels or alloys heated in carbon dioxide under pressure; Oxydation d'aciers ordinaires ou allies chauffes dans le gaz carbonique sous pression

    Leclercq, D; Chevilliard, C; Darras, R [Commissariat a l' Energie Atomique, Saclay (France).Centre d' Etudes Nucleaires

    1960-07-01

    Selection tests were carried out on commercial steels from the viewpoint of their resistance to oxidation in carbon dioxide, under 25 atmospheres pressure, between 350 and 600 deg. C. Comparative curve of oxidation kinetics were obtained, from which the influence of various additive elements can be found; small amounts of aluminium particularly seem to be favourable in the case of only slightly alloyed steels. (author) [French] Des essais de selection d'aciers commerciaux ont ete effectues quant a leur resistance a l'oxydation dans le gaz carbonique, sous pression de 25 atmospheres, ente 350 et 600 deg. C. Des courbes comparatives de cinetique d'oxydation ont ete obtenues, ce qui permet de degager l'influence de divers elements d'addition; de faibles teneurs en aluminium apparaissent notamment favorables dans le cas des aciers peu allies. L'acier inoxydable 18-8 a egalement ete etudie, notamment sous forme de tubes minces. Son comportement est bon jusqu'au moins 600 deg. C dans ces conditions. (auteur)

  4. Effect of different temperature-time combinations on physicochemical, microbiological, textural and structural features of sous-vide cooked lamb loins.

    Roldán, Mar; Antequera, Teresa; Martín, Alberto; Mayoral, Ana Isabel; Ruiz, Jorge

    2013-03-01

    Lamb loins were subjected to sous-vide cooking at different combinations of temperature (60, 70, and 80 °C) and time (6, 12, and 24 h). Different physicochemical, histological and structural parameters were studied. Increasing cooking temperatures led to higher weight losses and lower moisture contents, whereas the effect of cooking time on these variables was limited. Samples cooked at 60 °C showed the highest lightness and redness, while increasing cooking temperature and cooking time produced higher yellowness values. Most textural variables in a texture profile analysis showed a marked interaction between cooking temperature and time. Samples cooked for 24h showed significantly lower values for most of the studied textural parameters for all the temperatures considered. Connective tissue granulation at 60 °C and gelation at 70 °C were observed in the SEM micrographs. The sous-vide cooking of lamb loins dramatically reduced microbial population even with the less intense heat treatment studied (60 °C-6 h). Copyright © 2012 Elsevier Ltd. All rights reserved.

  5. Méthode d'estimation des tassements des sols fins sous les remblais d'infrastructures ferroviaires pour lignes à grande vitesse

    Said Alami, Soukaina; Reiffsteck, Philippe; Cuira, Fahd

    2018-02-01

    Le besoin de maîtriser les déformations des sols sous les remblais destinés à recevoir les structures de lignes à grande vitesse, en fait un enjeu important pour ces projets. Toutefois, de nombreuses difficultés ont été soulevées liées principalement au grand nombre d'incertitudes qui entourent le phénomène. En effet, la caractérisation géologique et géotechnique dépend de sondages et d'essais où le risque de remaniement est important et dont l'interprétation est, souvent, délicate. Cet article présente une procédure de calcul qui permettrait en pratique d'évaluer le tassement sous remblai avec une bonne précision et qui a été validée sur un certain nombre d'ouvrages. Pour cela, des corrections sont introduites aux méthodes usuelles de calcul permettant d'approcher les valeurs mesurées sur chantier.

  6. Intergranular Pressure Solution in Nacl: Grain-To-Grain Contact Experiments under the Optical Microscope Dissolution sous contrainte dans NaCl : expériences de contact grain à grain sous microscope optique

    Spiers C. J.

    2006-12-01

    effective diffusivity varying with contact force and on-going convergence. The results agree broadly with those of previous compaction creep experiments performed using wet halite powder. Discrepancies with other workers results for single-contact dissolution experiments can be explained in terms of differences in experimental configuration and competition between driving forces. La dissolution sous contrainte (IPS - Intergranular Pressure Solution représente un mécanisme de lithification, de compaction et de déformation à l'échelle géologique pour une large gamme de roches. Les études expérimentales d'IPS réalisées sur des agrégats de quartz n'ont pas été couronnées de succès en raison d'un taux faible d'IPS, et les expériences IPS réalisées en utilisant une halite saturée comme analogue de roche (Spiers et Schutjens, 1990 ; Hickman et Evans, 1991 ont laissé des incertitudes quant au détail des mécanismes IPS et à la structure/saturation au contact du grain dans ce matériau. La présente étude fait état de quatre expériences de dissolution de contact réalisées sous microscope optique afin d'étudier le mécanisme et la cinétique de l'IPS pour des contacts simples halite/halite et halite/verre, chargés en eau salée (température ambiante. Des forces normales de contact dans la gamme de 1,0 à 2,6 N ont été appliquées en présence d'eau salée saturée en NaCl, induisant des pressions de 0,8 à 7,4 MPa. Des pertes de masse et des convergences - fonction du temps - ont été observées pour tous les contacts. Dans tous les cas, le fait de charger le contact (ou d'augmenter la charge sur le contact a conduit à la formation immédiate d'une morphologie de contact rugueuse, composée d'un motif d'îles et de canaux, contrôlé par des caractéristiques cristallographiques, à l'échelle de quelques microns. Cette microstructure non équilibrée a évolué dans le temps vers une face de contact optiquement plate. Le processus de convergence

  7. Dimensionnement des actionneurs électriques alimentés à fréquence variable sous faible tension

    Biedinger, J.-M.; Vilain, J.-P.

    1999-09-01

    In Part I we present a multidisciplinary analysis model for the prediction of functional connections between the design variables and the electromagnetical, electrical and thermal performances of a brushless permanent magnet motor. In this paper we have elaborated a design methodology for electrical motors supplied from a variable-frequency low-voltage source. The objective is to take into account the influence of the inverter's dynamics from the beginning of the design, for the same reasons as we do for electromechanical and thermal constraints. The procedure is based on a Sequential Quadratic Programming optimization method. Two techniques are used to take into account the influence of the inverter: the first one develops the performance analysis with the multidisciplinary model; the second one considers the inverter's current reference as a supplementary optimization variable for the control of the design. Optimization difficulties linked to the chopping of the converter are discuted in connection with a sensitivity analysis of the torque, with respect to the inverter's current reference; a method is proposed to enhance the performances of the algorithm. The method has been applied to the design of a permanent magnet brushless DC motor used in the propulsion system of an electrical scooter; evolution of the design with the complexity level of analysis model is evidenced. Dans une première partie nous avons développé un modèle d'analyse pluridisciplinaire qui établissait les dépendances fonctionnelles entre les variables de conception et les performances magnéto-électro-thermiques d'un moteur brushless à aimants permanents. Dans cet article nous décrivons une procédure de dimensionnement adaptée à la conception de la machine alimentée à fréquence variable sous faible tension. L'objectif est d'intégrer la dynamique du convertisseur électronique dès la phase initiale du dimensionnement, au même titre que les spécifications

  8. L'intervention sous-marine : situation actuelle et perspectives d'avenir Underwater Operations and Techniques: Current Situation and Future Outlook

    Bertrand A. R. V.

    2006-11-01

    Full Text Available A l'occasion de la Conférence Internationale de Paris sur la Pénétration sous-marine(6-8 décembre 1982, cet article fait le point sur les différents moyens d'intervention sous-marine disponibles à ce jour (plongeurs, engins télécommandés, sous-marins à pression atmosphérique et sur un certain nombre de problèmes technologiques communs (matériaux, télémanipulation, navigation, sources d'énergie. Ce domaine est encore en pleine évolution et fait appel aux récentes innovations technologiques. Bien que les engins télécommandés semblent avoir actuellement la faveur des industriels, les autres moyens restent d'avenir prometteur, la complémentarité devant remplacer dans le futur la concurrence La résurrection de l'Argyronète qui doit devenir en 1985 un banc d'essais des nouvelles techniques est le témoignage de l'activité de ce secteur industriel. This article is based on the International Symposium in Paris on Underwater Operations and Techniques 6-9 December 1982. It reviews the different methods now available for underwater operations (divers, remote-controlled vehicles, atmospheric-pressure submarines and various technological problems common to all of them (materials, remote manipulation, navigating, power sources. This field is evolving rapidly and makes use of the most recent technological innovations. Although remote-controlled vehicles now seem to be favored by industrialists, the other methods still have a promising future, and the complementariness of these methods can be expected to replace rivalry among them. The resurrection of the Argyronète project, which should become a test bench for new techniques in 1985, is a good illustration of the activity going on in this industrial sector.

  9. The natural seismic hazard and induced seismicity of the european HDR (hot dry rock) geothermal energy project at Soultz-sous-Forets (Bas-Rhin, France); Alea sismique naturel et sismicite induite du projet geothermique europeen RCS (roche chaude seche) de Soultz-sous-Forets (Bas-Rhin, France)

    Helm, J A

    1996-06-07

    Development of the Soultz-sous-Forets HDR (Hot Dry Rock) geothermal energy project will involve important fluid injections which will induce micro-seismic events. This thesis discusses the natural seismicity of the region and induced seismicity associated with fluid injections. A catalogue of all historical and instrument seismicity of the Soultz-sous-Forets (SSF) region has been compiled. This seismicity does not correspond to movements along the major tectonic features of the region. The area around SSF has been identified as being one where high heat flow corresponds to low seismicity. The largest well documented seismic event in the region which took place in 1952 had an epicentral intensity of VI. All important data pertaining to the series of seismic events which took place in the region from August to October 1952 have been collected and are presented. This work details the installation and operation of a permanent 3 station network of accelerometers and seismometers around the HDR site. Also the installation and operation of a mobile network of vertical seismometers during fluid injections. 167 micro-seismic events were recorded on the surface network, with magnitudes from -0.5 to 1.9. The preferential alignment of the micro-seismic cloud is N160 deg. Individual focal mechanisms of the larger seismic events correspond to an extensional tectonic regime. Stress inversion of P wave polarities indicates that the maximum stress is vertical and the intermediate and minimum stress axes horizontal. The largest of the horizontal stresses is orientated N124 deg and the smallest N34 deg. Induced seismic movement is taking place on pre-existing fractures controlled by the in situ stress seismic movement is taking place on pre-existing tectonic fractures controlled by the in situ stress field, and the largest of the induced events had a magnitude 1.9. This level of seismicity does not pose any environmental hazard to the region around Soultz-sous-Forets. (author) 151

  10. Lutte contre le Bremia de la laitue en pépinière et sous abri froid : compte-rendu d'essai 2005

    Lambion, Jérôme

    2006-01-01

    Le mildiou de la laitue (Bremia lactucae) est la maladie la plus redoutée sur cette espèce, notamment en culture biologique d’hiver sous abris. En Provence, les dégâts sont très importants, parfois dès la pépinière, et entraînent de fortes pertes financières. Cette situation est due à deux facteurs principaux : d’une part au contournement récurrent des résistances génétiques par de nouvelles souches de Bremia (25 races déterminées à ce jour), et d’autre part à la faiblesse des méthodes de lut...

  11. Stress corrosion cracking of Inconel in high temperature water; Corrosion fissurante sous contrainte de l'Inconel dans l'eau a haute temperature

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

    1960-07-01

    Some Inconel samples were subjected to hot water corrosion testing (350 deg. C), under stress slightly above the elastic limit. It has been observed that different types of alloys - with or without titanium - could suffer serious intergranular damage, including a complete rupture, within a three months period. In one case, we observed an unusual intergranular phenomenon which appeared quite different from common intergranular corrosion. (author) [French] Des essais de corrosion d'Inconel sont realises dans l'eau a 350 deg. C, et sous contrainte legerement superieure a la limite elastique. On constate que differentes varietes d'alliage avec ou sans titane donnent lieu a des accidents intergranulaires graves allant jusqu'a rupture complete en 3 mois. Dans un cas, on observe un phenomene intergranulaire particulier tres different de la corrosion intergranulaire classique. (auteur)

  12. Le pardon ou l’oubli ? La réhabilitation judiciaire en France sous la IIIe République : le cas d’Angers

    Coltel, Antony

    2011-01-01

    La réhabilitation judiciaire constitue une forme essentielle du « pardon officiel » que la société française, sous la IIIe République, pouvait accorder aux anciens condamnés. La réhabilitation judiciaire s’applique à des condamnés ayant subi leur peine en bonne et due forme et non à des innocents injustement punis ayant obtenu la révision de leur procès. Il s’agit donc d’une mesure de pardon spécifique inaugurée par les codes napoléoniens, rétablissant le condamné dans ses droits et effaçant ...

  13. Processus d'innovation et recomposition des territoires agricoles : le cas du semis sous couvert végétal au nord du Cameroun

    Dugué, Patrick; Olina Bassala, Jean-Paul

    2015-01-01

    Au nord du Cameroun, l'adoption des systèmes de culture sous couvert végétal (SCV) butte sur le partage des résidus de culture fourragers en saison sèche entre le bétail et la couverture du sol. Elle nécessite donc d'accroître l'offre fourragère et de prendre en compte les différents types d'élevage (villageois, semi-sédentaire, transhumant, etc.). Dans les conditions actuelles de pratique des SCV par les producteurs (faible couverture du sol, peu d'années successives en SCV) les effets atten...

  14. Identité hors territoire. Les élites espagnoles exilées en France sous la dictature de Primo de Rivera (1923-1930

    Elvire Diaz

    2006-09-01

    Full Text Available Le territoire étant un point d’ancrage de l’identité individuelle et nationale, nous verrons dans ce travail si hors territoire, il peut y avoir préservation de l’identité, individuelle, collective, nationale, débouchant sur une dé-territorialisation, au sens défini par Gilles Deleuze. Notre objet d’étude portera sur le cas d’une micro-société hors territoire, les élites intellectuelles espagnoles exilées en France sous la dictature du Général Miguel Primo de Rivera (1923-1930.Le général Mig...

  15. Écrire dans la variante de l’autre : le cas de Sous les vents de Neptune de Fred Vargas

    Nadine Vincent

    2014-04-01

    Full Text Available Pour tout auteur, choisir d’écrire dans une langue ou dans la variante d’une langue qui n’est pas la sienne représente un défi de taille. Nous nous intéresserons au roman Sous les vents de Neptune, de l’écrivaine française Fred Vargas, qui a situé une partie de son intrigue au Québec, sans maîtriser la notion de variation linguistique. En analysant les réactions des lecteurs européens et québécois, de même que les caractéristiques de la langue québécoise de Vargas, nous aborderons la question de l’impérialisme linguistique et de son anachronisme au xxie siècle.

  16. "Velvet":Sous-titrage de l'épisode 1 de la série de R. Campos et G.R. Neira

    De Corte, Inès

    2017-01-01

    Sous-titrage du premier épisode de la série "Velvet" réalisée par R. Campos et G.R. Neira et produite par Bambú Producciones. Contextualisation de la série dans l'histoire et dans les jeux d'influences de l'industrie de la mode afin d'évaluer l'adaptation de la série et sa crédibilité historique. Commentaires de traduction expliquant le processus de traduction, la réflexion et la méthodologie employées. Master [120] en traduction, Université catholique de Louvain, 2017

  17. Gazettes sous influence : le Courrier du Bas-Rhin, la Gazette des Deux-Ponts et les sujets touchant la Russie vers 1770

    Georges Dulac

    2016-11-01

    Full Text Available Vers 1770, la campagne anti-russe du gouvernement français tend à dégrader l’image de la Russie, ce qui lèse gravement ses intérêts, notamment quand elle doit emprunter pour financer la guerre avec la Turquie. Aussi le prince Dmitri Alexeevitch Golitsyn, ministre plénipotentiaire à La Haye, se montre-t-il alors très actif sur ce terrain. Sa correspondance avec Pétersbourg témoigne de ses efforts, aux effets inégaux, pour influer sur les informations diffusées par quelques journaux : principalement le Courrier du Bas-Rhin, publié par Jean Manzon à Trèves, sous contrôle prussien, et dans une moindre mesure les deux Gazettes des Deux-Ponts, l’une politique, l’autre littéraire. Le journaliste de Trèves, qui trouve son intérêt à prendre le parti de la Russie, met en œuvre en sa faveur un discours journalistique abondant et parfois très élaboré. Cependant, la ligne du journal subit des fluctuations sensibles, selon l’évolution de la situation et à la suite de diverses interventions, dont celles du roi de Prusse et d’autre part de Stanislas-Auguste, qui pensionne un temps le journaliste. La Gazette des deux Ponts pratique l’information orientée avec plus de finesse, et, comme la gazette littéraire, accorde une large place à la matière russe : mais sur le plan politique, son traitement reste le plus souvent sous influence française et répond rarement aux vœux de D. A. Golitsyn.

  18. Prediction under Uncertainty on a Mature Field Prévision de production sous incertitude pour un champ mature

    Feraille M.

    2012-04-01

    uses Gaussian process modeling and an adaptive design strategy. In the final step of the workflow, parametric response surfaces are used to approximate the reservoir production forecasts and obtain their probabilistic distribution by propagating the remaining posterior uncertainty of input parameters. Dans le cadre de l’ingénierie de réservoir, des simulateurs permettent de comprendre et prédire le déplacement des fluides dans le réservoir et ainsi d’optimiser son exploitation. Ces simulateurs prennent en entrée un grand nombre de paramètres qui peuvent être entachés d’incertitudes. Afin d’assurer une production future correcte, la comparaison des différents scénarios d’exploitation possibles doit tenir compte de ces incertitudes. Les prévisions de production ne doivent pas être évaluées en ne considérant qu’un seul cas « moyen » pour chaque scénario mais en intégrant l’incertitude sur les paramètres d’entrée. Dans le cadre de champ mature où un historique de production est disponible, le formalisme Bayésien est bien adapté pour répondre au problème des prédictions sous incertitudes. En effet, il permet de définir les incertitudes, dites a posteriori, sur les entrées du modèle de réservoir en prenant en compte à la fois les données statiques et dynamiques. Ces incertitudes a posteriori peuvent ensuite être propagées afin de calculer des prévisions de production probabilistes pour chaque scénario, tout en respectant la connaissance statique et dynamique du réservoir. Mais l’obtention des incertitudes a posteriori ainsi que la propagation de celles-ci sur les prévisions de production nécessitent un nombre souvent prohibitif de simulations du modèle réservoir. Dans cet article, nous proposons une application de plusieurs techniques statistiques avancées afin de prendre en compte les incertitudes dans les prévisions de production pour un champ mature et ce en utilisant un nombre raisonnable de simulations. Le

  19. Evolution de la perméabilité d'agrégats de sels sous contrainte liée à des circulations de fluides : dissolution, colmatage, déformation

    Chen , Tao

    1994-01-01

    Le but de ce travail est d'étudier l'évolution de la perméabilité d'agrégats de sels sous contrainte lorsque les fluides circulant dans ces agrégats peuvent réagir avec le solide par des dissolutions et/ou des colmatages. Des essais de circulation de divers fluides à travers des échantillons de briques de sels sous contrainte ont permis de suivre l'évolution de la composition des fluides en cours d'essai. L'évolution des matériaux a été aussi caractérisée en cours d'essai (mesure de vitesse a...

  20. Effet de pratiques de fertilisation azotée sur la sensibilité d’une culture de tomate à l’oïdium et la pourriture grise en conditions de production sous serre.

    Ozayou, Saddik

    2011-01-01

    L’azote est le principal élément nutritif utilisé pour le contrôle des maladies aériennes sous abris. Dans ce stage, nous avons étudié l’effet de trois régimes de fertilisation azotée (4 mmoles/L, 8 mmoles/L et 16 mmoles/L) sur la physiologie de la plante et la sensibilité de la tomate à l’Oidium neolycopersici et à Botrytis cinerea en conditions de production sous serre. Pour ce faire, nous avons inoculé différents organes aériens des plantes dans la serre ou au laboratoire de l’INRA d’Alény...

  1. A continuous acceleration tube of ions under 200 KV; Un tube d'acceleration continue d'ions sous 200 KV

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

    1954-07-01

    The realization of an Van de Graaff accelerator required, for the preliminary studies, the construction of a small proton accelerator, functioning at 200 kV in order to resolve some parasitic effects inherent to the accelerators tubes. The aim of this report is to describe the different organs of the accelerator tube, to explain the operating system and to encode their characteristics. The report first presents the ion source and the beam buncher permitting to inject in the accelerator tube particles of about 9 kV and very batched in a thin beam of circular section. Then the study explain the tube characteristics considered like optic system. A method to obtain precise calculation of particle trajectories is exposed. Aberrations of the system were discussed and balance of the currents on all electrodes inside the tube for different regimes of working were provided. The influence of the residual pressure in the tube were explained. The report finally ends on a part of the fundamental problem of the straining occurring inside the tubes accelerators under high tension. (M.B.) [French] La realisation d n accelerateur du type Van de Graaff a necessite, entre autres etudes preliminaires, la construction d'un petit accelerateur de protons, fonctionnant sous 200 kV afin d'eclaircir certains effets parasites propres aux tubes accelerateurs. L'objet de ce rapport est de decrire les differents organes du tube accelerateur, d'en expliquer le fonctionnement et de chiffrer leurs caracteristiques. Le memoire presente d'abord la source d'ions et le canon permettant d'injecter dans le tube accelerateur des particules de 9 kV environ et bien groupees dans un faisceau fin de section circulaire. Puis il passe a l'etude du tube considere comme systeme optique. Une methode utilisee pour le calcul precis des trajectoires des particules y est exposee. Il aborde le probleme des aberrations de ce systeme et fournit par la suite le bilan des courants sur toutes les electrodes a l

  2. High vacuum high temperature x-ray camera (1961); Chambre de diffraction de rayons x a haute temperature sous vide pousse (1961)

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

    1961-07-01

    - This camera makes it possible to carry out X-ray studies on highly oxidisable materials, up to about 900 deg. C. Most of the existing models do not provide sufficient protection against the formation of surface oxide or carbide films on the sample. The present arrangement makes it possible to operate at very low pressures: 5 x 10{sup -8} to 10{sup -7} torr, thanks to an entirely metallic apparatus. The radiation heating system consists of an incandescent lamp, outside the evacuated portion, and a reflector which concentrates the energetic flux into the sample through a silica window. The heated parts have thus only a small thermal inertia. With the apparatus it has been possible to determine the phase parameters of uranium-{alpha} up to 650 deg. C with a precision of {+-} 0.0015 A. A similar study has been carried out on a uranium-chromium alloy in the {beta}-phase up to 740 deg. C. (author) [French] Cette chambre permet l'etude, par diffraction de rayons X, de materiaux tres oxydables, ceci jusqu'a 900 deg. C environ. La plupart des modeles existant a l'heure actuelle n'assurent pas une protection suffisante de l'echantillon contre la formation de films superficiels d'oxydes ou de carbures. La disposition d'ensemble permet d'operer sous des pressions tres basses: 5.10{sup -8} a 10{sup -7} torr, grace a une construction entierement metallique. Le systeme de chauffage par rayonnement associe une lampe a incandescence, exterieure a l'enceinte sous vide, et un reflecteur, qui concentre le flux energetique sur l'echantillon, a travers un hublot de silice. Les pieces echauffees ne presentent ainsi qu'une faible inertie thermique. L'appareil a permis la determination des parametres de l'uranjum en phase a, jusqu'a 650 deg. C, avec une precision de {+-} 0,0015 A. Une etude similaire a ete effectuee sur un alliage uranium-chrome, en phase {beta}, jusqu'a 740 deg. C. (auteur)

  3. Effect of Grapefruit Seed Extract on Thermal Inactivation of Listeria monocytogenes during Sous-Vide Processing of Two Marinated Mexican Meat Entrées.

    Valenzuela-Melendres, Martin; Peña-Ramos, E Aida; Juneja, Vijay K; Camou, Juan Pedro; Cumplido-Barbeitia, German

    2016-07-01

    D- and z-values for Listeria monocytogenes were obtained for two Mexican meat entrées: pork meat marinated in tomatillo (green tomato) sauce (PTS) and beef marinated in a red chili sauce (BRCS), with addition of 0, 200, and 800 ppm of grapefruit seed extract (GSE). Meat samples inoculated with L. monocytogenes were packaged in sterile bags, immersed in a water bath, and held at 55, 57.5, 60, and 62.5°C for different periods of time. Depending upon the temperature, D-values at 0 ppm of GSE ranged from 26.19 to 2.03 min in BRCS and 26.41 to 0.8 min in PTS. Adding 800 ppm of GSE to BRCS thermally treated at 55 and 62.5°C significantly decreased inactivation time by 35%. A reduction in time of 25.9, 10.6, and 40.1% at 55, 57.5, and 60°C, respectively, was observed in PTS with 800 ppm of GSE. The z-values of L. monocytogenes were not significantly affected by GSE addition; average z-values were 7.25 and 5.09°C for BRCS and PTS, respectively. Estimated thermal lethality for a 7-D log reduction of L. monocytogenes under commercial-size sous-vide conditions at a reference temperature of 55°C was reached at 78 and 71 min for BRCS without and with 800 ppm of GSE, respectively. For PTS, 7-D reduction was attained at 69 and 61 min without and with addition of 800 ppm of GSE, respectively. Supplementing both Mexican meat entrées (BRCS and PTS) with 800 ppm of GSE rendered L. monocytogenes cells more sensitive to the lethal effect of heat. The results of this study will assist the retail food industry in designing acceptance limits on critical control points pertaining to cooking regimes to effectively eliminate L. monocytogenes in BRCS and PTS sous-vide processed Mexican meat entrées.

  4. L'interdépendance entre les sous-systèmes conjugal et parental: une analyse personne-processus-contexte

    Bigras Marc

    2000-01-01

    Full Text Available Dans le présent article nous étudions les mécanismes de transmission des difficultés socioaffectives entre les systèmes conjugal et parental sous l'effet d'une part de stress contextuels comme la pauvreté des familles et, d'autre part, des caractéristiques personnelles des membres de ces familles comme le sexe et l'âge de l'enfant. Un échantillon de couples avec ou sans enfant permet dans une première étude d'estimer l'impact de la présence de l'enfant sur le couple alors que deux autres études posent la question complémentaire de l'impact du couple sur l'enfant. Les résultats de ces études contribuent à démontrer l'interdépendance entre le couple et l'enfant alors que chaque membre de la famille peut-être une source d'influence sur les autres. Nous argumentons qu'une réponse aversive à des problèmes extrafamiliaux favorise des stress intrafamiliaux mais que cela se révèle surtout selon les caractéristiques des membres de la famille.

  5. Critical and sub-critical experiments on U-BeO lattices; Experiences critiques et sous-critiques sur reseaux U-BeO

    Benoist, P.; Gourdon, Ch.; Martelly, J.; Sagot, M.; Wanner, G. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires; Deniz, V.; Joshi, B.V.; Sahai, K. [Atomic Energy Establishment Trombay (India)

    1958-07-01

    Sub-critical experiments have allowed us to measure the material buckling of uranium natural oxide of beryllium lattices with a grid of 15 cm, and made up of uranium bars measuring 2.60 - 2.92 - 3.56 and 4.40 cm of diameter. A critical experiment has then been conducted with hollow 1.35 per cent enriched uranium bars. A study of U-BeO 18.03 cm grid lattices is at present being conducted. (author)Fren. [French] Nous avons mesure par des experiences sous-critiques le laplacien matiere de reseaux uranium naturel-oxyde de beryllium, dont la maille carree a un pas de 15 cm, realises avec des barreaux d'uranium de diametres 2,60 - 2,92 - 3,56 - 4,40 cm. Une experience critique a ete faite ensuite avec des barres creuses d'uranium enrichi a 1,35 pour cent; l'etude des reseaux U-BeO de pas 18,03 cm est actuellement en cours. (auteur)

  6. Effects of sous-vide method at different temperatures, times and vacuum degrees on the quality, structural, and microbiological properties of pork ham.

    Jeong, Kiyoung; O, Hyeonbin; Shin, So Yeon; Kim, Young-Soon

    2018-04-10

    This study evaluated the influence of different factors on pork hams cooked by sous-vide method. The quality and structural and microbiological properties of the treated samples were compared with those of controls. Samples were subjected to treatment at different combinations of temperature (61 °C or 71 °C), time (45 or 90 min), and vacuum degree (98.81% or 96.58%). The control sample was air packaged and boiled for 45 min in boiling water. Temperature and vacuum degree affected quality properties, while the effect of time was limited. Samples cooked at 61 °C showed higher moisture content, redness, and pink color of the meat juice, whereas samples cooked at 71 °C showed higher cooking loss rate, lightness, and volatile basic nitrogen values. Texture analysis indicated tenderer meat for the treatment group than the control. No microbial growth was detected in any treatment groups. Meat cooked at 61 °C and 98.81% vacuum showed more spacious arrangement of meat fiber. Copyright © 2018 Elsevier Ltd. All rights reserved.

  7. Proceedings of the European Symposium on Pressure Equipment - ESOPE 2007; Actes des Journees d'Etudes Europeennes Equipements sous Pression - ESOPE 2007

    NONE

    2007-07-01

    orientations retained for pressure equipments used in the nuclear industry, the European standards and the international collaboration, the Chinese standards and finally the recent developments of the codes and standards of the ASME in the USA. ESOPE 2007 also includes a Poster Session organized in the context of the international exhibition, which allows the companies to present their industrial realizations in parallel to the Symposium. (author) [French] Tous les trois ans, et depuis maintenant trente ans, l AFIAP organise un symposium ou les experts et acteurs oeuvrant dans le domaine des equipements sous pression, qu'ils soient fixes ou transportables, peuvent se rencontrer et echanger sur tous les developpements touchant a leur activite. Ce qui etait dans un premier temps denomme 'Congres national sur la technologie des appareils a pression', puis 'Journees d'etude sur les appareils a pression', est devenu depuis 2001 les 'Journees d'etude Europeennes sur les equipements sous pression' ou encore 'European Symposium on Pressure Equipment' (ESOPE), marquant ainsi une volonte d'ouverture a l'Europe et a l'international dans un contexte marque par la mise en oeuvre des directives europeennes applicables a ces equipements. Les journees 2001 furent plus particulierement consacrees a la mise en oeuvre des directives harmonisant la construction des equipements, et les journees 2004 ont ete plus particulierement axees sur la gestion des equipements en service. Pour le symposium ESOPE 2007, le comite d organisation a souhaite reprendre ces deux themes sous les aspects de la securite et de la competitivite, ainsi que de l'innovation. La seance pleniere du dernier jour sera entierement consacree a ces themes et comportera une Table Ronde ou s'exprimeront des representants nationaux et europeens des pouvoirs publics, des representants des fabricants et utilisateurs, ainsi que des experts engages dans la

  8. Critical and sub-critical experiments on U-BeO lattices; Experiences critiques et sous-critiques sur reseaux U-BeO

    Benoist, P; Gourdon, Ch; Martelly, J; Sagot, M; Wanner, G [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires; Deniz, V; Joshi, B V; Sahai, K [Atomic Energy Establishment Trombay (India)

    1958-07-01

    Sub-critical experiments have allowed us to measure the material buckling of uranium natural oxide of beryllium lattices with a grid of 15 cm, and made up of uranium bars measuring 2.60 - 2.92 - 3.56 and 4.40 cm of diameter. A critical experiment has then been conducted with hollow 1.35 per cent enriched uranium bars. A study of U-BeO 18.03 cm grid lattices is at present being conducted. (author)Fren. [French] Nous avons mesure par des experiences sous-critiques le laplacien matiere de reseaux uranium naturel-oxyde de beryllium, dont la maille carree a un pas de 15 cm, realises avec des barreaux d'uranium de diametres 2,60 - 2,92 - 3,56 - 4,40 cm. Une experience critique a ete faite ensuite avec des barres creuses d'uranium enrichi a 1,35 pour cent; l'etude des reseaux U-BeO de pas 18,03 cm est actuellement en cours. (auteur)

  9. Hot pressing of U-UC cermets and stoichiometric uranium monocarbide; Preparation par frittage sous charge de cermets U-UC et de monocarbure stoechiometrique

    Dubuisson, J; Houyvet, A; Le Boulbin, E; Lucas, R; Moranville, C [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1958-07-01

    High density fuels, either in uranium monocarbide or in U-UC cermets have been prepared on laboratory-scale, by hot pressing of mixtures of uranium powder and graphite in suitable proportions. Uranium powder is prepared by calcium reduction of UO{sub 2} followed by an acetic leaching at low temperature. An adequate protection-treatment permits the manipulation of the powder in the open air. Uranium and Graphite powders are intimately mixed and then hot pressed in a double effect graphite die at a temperature of 900-1000 deg. C under a charge of 200 kg/cm{sup 2} during 3 hours. A special design of the die avoids the breaking of the graphite during the sintering. In this way, samples are prepared, the characteristics of which are: 1) {+-} 5 pour cent of homogeneity for a ratio height/diameter = 2. 2) almost theoretical density (98 pour cent) 3) low concentration of unreacted carbon (heat treatment of stoichiometric monocarbide can be useful for completion of reaction) 4) the micrographic examination shows: - a network of monocarbide surrounding uranium in the case of low concentration cermets (<2,5 per cent C) - two networks intimately mixed for high concentration cermets (<2,5 per cent C) - a fine grain structure for the monocarbide (10 u). 5) In every case, the X rays examinations show a fine grain structure without any orientation, and no UC{sub 2}. Some indications are given on the physical (thermal cycling, conductibility) and chemical properties (corrosion, reaction with cladding materials). (author)Fren. [French] Une methode de preparation de combustibles de haute densite, soit en monocarbure d'uranium, soit en cermets U-UC, a ete mise au point au laboratoire. Il s'agit du frittage sous charge de melanges de poudres d'uranium et de graphite en proportion convenable. La poudre d'uranium est elaboree par calciothermie de l'oxyde UO{sub 2} suivie d'un lavage acetique a basse temperature. Un traitement de protection adequat pe sa manipulation a l'air. Les poudres

  10. The Influence Of Hydrothermal Alteration And Weathering On Rock Magnetic Properties Of Granites From The Eps-1 Drilling (soultz-sous-forÊts / France)

    Just, J.; Schleicher, A.; Kontny, A.; de Wall, H.

    The EPS-1 drilling in Soultz-sous-Forêts (Rhinegraben, France) recovered a core pro- file of Tertiary to Permo-Mesozoic sediments deposited on a Variscan granitic base- ment. Magnetic susceptibility (k) measurements on the core material revealed a con- tinous increase from the basement/cover boundary (kmean 0.4 x 10-3 SI) into the magnetite-bearing granite (kmean 13 x 10-3 SI) over a depth range of 1417 U 1555 m. Rock magnetic and mineralogic studies were performed for the fresh granite, the hydrothermally altered granite near a fault zone and the altered granite from the fossil land surface near the basement/cover boundary. The decrease in susceptibility can be correlated with a gradual decomposition of magnetite to hematite and an alteration of the matrix minerals feldspars, biotite and hornblende to clay minerals and carbon- ates. Along with this transition, characteristic rock magnetic signatures can be dis- criminated for different degrees of alteration. While temperature-dependent magnetic susceptibility k(T)-curves in fresh granites indicate a typical multidomain magnetite course with good reversibility, different types of irreversible courses are observed for the altered granite. However, hematite could not be identified in the k(T)-curves. Al- tered granite shows relatively weak magnetic behaviour in AF-demagnetisation exper- iments, untypical for hematite. The alteration of the fresh granite also causes a change in magnetic fabric parameter, especially of the anisotropy factor. The magnetic min- eralogy from the altered granite in respect to the changes in rock magnetic properties will be discussed.

  11. Influences de la symphonie concertante sur la musique de la Cour parisienne sous l'Empire et la Restauration (1800-1830

    Dratwicki, Alexandre

    2003-12-01

    Full Text Available The origins of the very much appreciated "symphonie concertante" can be found in the importance of public concerts given in Paris at the end of the 18th century. The specific repertoire played at the French Court during the years 1800-1830 distinctly shows this vogue for the "symphonie concertante", for it reveals the still unknown importance of virtuosity. Considered as an musical entertainment for the pompous parties at the French Court or as an musical accompaniment for the masses given at the Imperial and Royal Chapel, this "decorative concertant syle" became an essential part of the Regime etiquette during the Napoleonic empire as well as the Restoration period. This music, perfectly incorporated into the official guidelines, will disappear as a consequence of the political events of 1830 and the arrival of a new aesthetic movement, the Romanticism.

    [fr] La vogue du concert public à Paris, à la fin du XVIIIe siècle, fut à l'origine de l'essor phénoménal que connut la symphonie concertante. Le répertoire de la musique de la Cour - entre 1800 et 1830 - est particulièrement représentatif de cette mode : il révèle une place encore insoupçonnée laissée à la virtuosité. Agrémentant les messes de la Chapelle ou les bals donnés lors de fastueuses soirées, ce « style concertant décoratif » devint un élément constitutif de l'apparat gouvernemental sous l'Empire et la Restauration. Une sorte d'académisme officiel que les événements politiques de 1830 et l'essor du romantisme musical feront définitivement disparaître.

  12. Experimental and numerical study of the stability of phyllosilicates in a strong thermal gradient. Test in the geothermal site of Soultz-sous-Forets

    Baldeyrou-Bailly, A.

    2003-01-01

    Thermodynamic data of hydrated phyllosilicates, in particular clay minerals are not well known. The stability fields of these minerals are not well determined; following some authors they even do not exist. We have developed an experimental approach, in which a sequence of local equilibrium states between a fluid and minerals take place in a closed gold cell along a strong thermal gradient. The experiments were conducted in the chemical systems: Mg-Al-Si-H 2 O (MASH), K-Al-Si-H 2 O (KASH), and K-Mg-Al-Si-H 2 O (KMASH). The sequences of crystallization observed along the thermal gradient are the same if one exchanges the position of the cells containing the initial reacting materials with respect to the thermal gradient end-members. The crystallization sequences correspond to local equilibrium states. Following the temperature increase (from 200 to 350 C) one observes the following sequences: di-octahedral smectite? tri-octahedral smectite; kaolinite? donbassite? tri-octahedral chlorite; smectite? illite? muscovite; or even kaolinite? illite + smectite? donbassite; commonly observed in hydrothermal systems. They allow to develop a thermodynamic model for hydrated phyllosilicates, taking into account their hydration state as a function of temperature. This model shows the stability fields of clay minerals between 200 and 350 C.The chemical and mineralogical dynamics showed in these experimental systems has been applied to predict the possible dissolutions and/or precipitations which may take place between the circulated hot fluid and the geothermal granitic reservoir in the geothermal system at Soultz-sous-Forets. These processes may affect the duration of the geothermal reservoir, as a function of evolution in the morphology of the porosity. Our experimental approach shows that feldspars and smectites are forming the major part of the total volume of silicates which may precipitate in addition to carbonates already described in previous studies. (author)

  13. Characterization and interpretation of a fractured rocky massif from borehole data. Boreholes of geothermal project at Soultz-sous-Forets and other examples of unidirectional sampling; Caracterisation et interpretation d`un volume rocheux fracture a partir de donnees de forages. Les forages geothermiques de Soultz-sous-Forets et autres exemples d`echantillonnages unidirectionnels

    Dezayes, CH

    1995-12-18

    In this thesis, we study fractures from borehole data on two sites: in one, located at Soultz-sous-Forets (Alsace) in the Rhine graben, boreholes reach a delta Jurassic series forming a petroleum reservoir. At Soultz, fractures have been studied on cores and borehole images. Striated faults present on cores permit to determine the tectonic history of the granite, completed by field study in Vosges Massif. This history corresponds to the Rhine graben history knowing by different authors. The analysis of vertical induced fractures observed on borehole images indicates a present-day NW-SE to NNW-SSE compression. These variations of stress direction are confirmed by others in situ measurements, as hydraulic injection, micro-seismicity, etc... On cores and borehole images, numerous fractures have been observed. Most of them are linked to the E-W distension, which permits the Rhine graben opening at Oligocene. At greatest scale, in quartz minerals, the micro-fractures are constitute by fluid inclusion trails. Several sets are related to the E-W distension, but others sets are linked to compressive stages. These sets are not observed on cores. This is a under-sampling of some fractures by the boreholes, but theses fractures exit into to rock massif. On borehole images, fracture density is weakest than the cores, however the set organisation is the same. At Ravenscar, the distribution of fracture spacing along different unidirectional sampling shows a exponential negative law. However, the fracture density varies with sampling. (author) 199 refs.

  14. Contribution of the Surface and Down-Hole Seismic Networks to the Location of Earthquakes at the Soultz-sous-Forêts Geothermal Site (France)

    Kinnaert, X.; Gaucher, E.; Kohl, T.; Achauer, U.

    2018-03-01

    Seismicity induced in geo-reservoirs can be a valuable observation to image fractured reservoirs, to characterize hydrological properties, or to mitigate seismic hazard. However, this requires accurate location of the seismicity, which is nowadays an important seismological task in reservoir engineering. The earthquake location (determination of the hypocentres) depends on the model used to represent the medium in which the seismic waves propagate and on the seismic monitoring network. In this work, location uncertainties and location inaccuracies are modeled to investigate the impact of several parameters on the determination of the hypocentres: the picking uncertainty, the numerical precision of picked arrival times, a velocity perturbation and the seismic network configuration. The method is applied to the geothermal site of Soultz-sous-Forêts, which is located in the Upper Rhine Graben (France) and which was subject to detailed scientific investigations. We focus on a massive water injection performed in the year 2000 to enhance the productivity of the well GPK2 in the granitic basement, at approximately 5 km depth, and which induced more than 7000 earthquakes recorded by down-hole and surface seismic networks. We compare the location errors obtained from the joint or the separate use of the down-hole and surface networks. Besides the quantification of location uncertainties caused by picking uncertainties, the impact of the numerical precision of the picked arrival times as provided in a reference catalogue is investigated. The velocity model is also modified to mimic possible effects of a massive water injection and to evaluate its impact on earthquake hypocentres. It is shown that the use of the down-hole network in addition to the surface network provides smaller location uncertainties but can also lead to larger inaccuracies. Hence, location uncertainties would not be well representative of the location errors and interpretation of the seismicity

  15. Space-time dependent impulse response of a subcritical cylindrical reactor; Reponse impulsionnelle spatio-temporelle d'un reacteur cylindrique en regime sous-critique

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

    1965-07-01

    In this paper, a new formulation of the spatial dependent impulse response of a subcritical reactor in a cylindrical geometry is proposed. An expression of the transfer function between a point source at the center of coordinates and the flux at a given point (r,z) is obtained by solving: by means of Laplace transform, the one group diffusion equation. In this transfer function, variables r and p (p being the Laplace variable) remain linked within a modified Bessel function. Taking the inverse Laplace transform is done by two different ways: - using the Mellin-Fourier method which separates variables r and t. This method makes it possible to establish that there is identity between the classical formulation and the new one. - using an inverse Laplace transform which keeps variables r and t linked. This method requires to approximate the inverse Laplace transform of the end factor. It is then possible to replace the radial harmonics modes series of the classical expression by a single function. This new formulation seems to be of particular interest when dealing with reactors of large size and lifetime. It is also interesting each time the harmonics play an important role. (author) [French] Dans le present rapport, on propose une nouvelle formulation de la reponse impulsionnelle spatio-temporelle d'un reacteur sous-critique, en geometrie cylindrique. Une expression de la fonction de transfert entre une source ponctuelle placee au centre des coordonnees et le flux au point courant (r,z) est obtenue en resolvant, par transformation de Laplace, l'equation de la diffusion a un seul groupe d'energie. Dans cette fonction de transfert, les variables r et p (variable de Laplace) demeurent groupees dans une fonction de Bessel modifiee. Le retour a l'original est effectue de deux manieres: - la methode de Mellin-Fourier qui separe les variables r et t, permet d'etablir l'identite entre la nouvelle formulation et la formulation classique. - un original conservant les variables

  16. Numerical modeling of the impact of temperature on the behavior of minerals in the Soultz-sous-Forêts enhanced geothermal system

    Van Ngo, Viet; Lucas, Yann; Clément, Alain; Fritz, Bertrand

    2015-04-01

    Operation of the enhanced geothermal system (EGS) requires to re-inject fluid, after heat exchange at the surface to the energy production, into the geothermal reservoir. This cold re-injected fluid can cause a strong disequilibrium with the fluid and granitic rock within the geothermal reservoir and then implies the possible dissolution/precipitation of minerals. The hydrothermal alterations include the transformation of plagioclase, biotite and K-feldspar and the precipitation of various secondary minerals. The major sealing phases observed in the main fracture zones are quartz, calcite, and clay minerals. These mineralogical transformations may modify the porosity, permeability and fluid pathways of the geothermal reservoir. In the Soultz-sous-Forêts EGS (Alsace, France), the hydraulic connection between the injection well and the production well is quite poor. Therefore, understanding the impact of changes in temperature, which are caused by the re-injected fluid, on the behavior of minerals (especially for the main newly-formed minerals such as quartz, calcite and clay minerals) is a critical preliminary step for the long-term prediction of their evolution. The approach used in the present work is typically based on a geochemical code, called THERMA, which enables to calculate the changes in equilibrium constants of all primary and secondary minerals and aqueous species as a function of temperature. Our model accounted for a wide range of different mineral groups in order to make sure a large freedom for the numerical calculations. The modeling results showed that when the temperature of geothermal reservoir is cooled down, quartz, calcite, illites, galena and pyrite have tendency towards equilibrium state, which indicates that they are precipitated under the geothermal conditions. In contrast, other minerals including plagioclase, K-feldspar and biotite remained unsaturated. These behaviors of minerals were further illustrated by the Khorzinsky stability

  17. Oxidation of iron and steels by carbon dioxide under pressure (1962); Oxydation du fer et des aciers par l'anhydride carbonique sous pression (1962)

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

    1962-07-01

    After having developed one of the first thermo-balances to operate under pressure, we have studied the influence of the pressure on the corrosion of iron and steels by carbon dioxide. The corrosion was followed by three different methods simultaneously: by the oxidation kinetics, by micrographs, and by radiocrystallography. We have been able to show that the influence of the pressure is not negligible and we have provided much experimental evidence: oxidation kinetics, micrographic aspects, surface precipitation of carbon, metal carburization, the texture of the magnetite layer. All these phenomena are certainly modified by changes in the carbon dioxide pressure. In order to interpret most of our results we have been led to believe that the phenomenon of corrosion by CO{sub 2} depends on secondary reactions localised at the oxide-gas interface. This would constitute a major difference between the oxidation by CO{sub 2} and that by oxygen. (author) [French] Apres avoir etudie et mis au point une des premieres thermobalances fonctionnant sous pression, nous avons etudie l'influence de la pression sur la corrosion du fer et des aciers par l'anhydride carbonique. Notre etude a ete conduite simultanement sur trois plans differents: etude des cinetiques d'oxydation, etude micrographique et etude radiocristallographique. Nous avons pu montrer que l'influence de la pression n'etait pas negligeable et nous en avons fourni un faisceau de preuves experimentales important: cinetiques d'oxydation, aspect micrographique, precipitation superficielle de carbone, carburation du metal, texture de la couche de magnetite. Tous ces phenomenes sont sans aucun doute modifies par une variation de pression du gaz carbonique. Pour interpreter la plupart de nos resultats, nous avons ete conduits a penser que le phenomene de corrosion par CO{sub 2} etait tributaire de reactions secondaires localisees a l'interface oxyde-gaz. Ce serait la une des differences fondamentales entre l'oxydation par

  18. Compatibility of various magnesium alloys with pressurized carbon dioxide at high temperatures; Compatibilite de divers alliages de magnesium avec le gaz carbonique sous pression aux temperatures elevees

    Dewanckel, B; David, R; Hulin, C; Leclercq, D [Commissariat a l' Energie Atomique, 38 - Grenoble (France). Centre d' Etudes Nucleaires

    1968-07-01

    This work on the compatibility of magnesium alloys with pressurized carbon dioxide has been carried out along three lines: - testing of special alloys containing additions of zirconium, manganese, cerium, zinc, beryllium and yttrium. The results are satisfactory, generally speaking, and the corrosion kinetics are often comparable to those of conventional magnesium-zirconium alloy; - influence of the quality of the carbon dioxide, in particular the presence of water vapour or of carbon monoxide in this gas. It appears that oxidation is reduced if the carbon dioxide contains traces of water vapour, but is more pronounced if carbon monoxide is also present; - study of certain phenomena related to corrosion: size changes in the samples during tests, structural modifications in the alloys (grain-size changes, formation of a cortical zone in the case of alloys containing zirconium). The influence of thermal cycling has also been studied in a few specific tests. The results obtained make it possible to compare the behaviour of various alloys under varying conditions of long-term use, and to choose, if required, the best composition for a given application. (authors) [French] Ce travail sur la compatibilite des alliages de magnesium avec le gaz carbonique sous pression a ete particulierement oriente dans trois directions: - epreuve, d'alliages speciaux comportant des additions de zirconium, manganese, cerium, zinc, beryllium et yttrium. Les resultats sont generalement satisfaisants et les cinetiques de corrosion souvent comparables a celles de l'alliage magnesium-zirconium classique; - influence de la qualite du gaz carbonique, et notamment de la presence de vapeur d'eau ou d'oxyde de carbone dans ce gaz. Il est apparu que l'oxydation est reduite si le gaz carbonique contient des traces d'eau, mais accrue si l'oxyde de carbone est egalement present; - etude de certains phenomenes lies a la corrosion: variations dimensionnelles des echantillons au cours des essais

  19. Texturation à froid sous contraintes triaxiales de phase à haute T_c de Bi(Pb)SrCaCuO préréagie

    Langlois, P.; Massat, H.; Suryanarayanan, R.

    1994-11-01

    The alignment of grains in isostatically precompacted samples of prereacted Bi{1,8}Pb{0,4}Sr{2,0}Ca{2,2}Cu{3,0}O{10,3 + x} powder has been achieved by compressive plastic deformation under isostatic pressure at room temperature. Isostatic pressures were in the range 0.1 to 1 GPa and deformation rates were led up to 57 %. Prior to sintering, X-ray diffraction measurements corroborate an expected high- T_c phase purity of nearly 85 % and indicate that the as-deformed samples have been textured with the (c-axes parallel to the pressing direction whilst a.c. susceptibility measurements ascertain a high transition temperature around 107 K. Intergranular connection does not occur until sintering at 850 ^{circ}C for 80 h and measurements indicate then that the texture has been retained. Superconducting properties themselves show sensitivity to texture through anisotropy-related distinctive irreversibility lines. L'alignement de grains de poudre Bi{1,8}Pb{0,4}Sr{2,0}Ca{2,2}Cu{3,0}O{10,3 + x} préréagie a été réalisé par déformation plastique à température ambiante d'échantillons précompactés isostatiquement et comprimés sous pression isostatique, la gamme des pressions isostatiques allant de 0,1 à 1 GPa et les taux de déformation atteignant 57 %. Les mesures de diffraction de rayons X corroborent la pureté de phase à haute T_c proche de 85 % attendue et indiquent que les échantillons ainsi déformés ont été texturés avec les plans ab perpendiculaires à la direction de compression. Les mesures de susceptibilité alternative avèrent une température élevée de transition à environ 107 K mais la connexion intergranulaire n'est assurée qu'après un frittage à 850 ^{circ}C pendant 80 h dont on vérifie qu'il conserve la texture. Enfin, la sensibilité des propriétés supraconductrices à la texturation est évaluée par le biais de lignes d'irréversibilité distinctes en fonction de l'anisotropie.

  20. Applications of sub-optimality in dynamic programming to location and construction of nuclear fuel processing plant; Application de la sous-optimalite en programmation dynamique a la localisation et la cadence optimales de construction des equipements

    Thiriet, L; Deledicq, A [Commissariat a l' Energie Atomique, 92 - Fontenay-aux-Roses (France). Centre d' Etudes Nucleaires, section des etudes economiques generales

    1968-09-01

    First, the point of applying Dynamic Programming to optimization and Operational Research problems in chemical industries are recalled, as well as the conditions in which a dynamic program is illustrated by a sequential graph. A new algorithm for the determination of sub-optimal politics in a sequential graph is then developed. Finally, the applications of sub-optimality concept is shown when taking into account the indirect effects related to possible strategies, or in the case of stochastic choices and of problems of the siting of plants... application examples are given. (authors) [French] On rappelle d'abord l'interet de la Programmation Dynamique dans les problemes d'optimisation et de Recherche Operationnelle dans les industries chimiques, et les conditions de representation d'un programme dynamique par un graphe sequentiel. On expose ensuite un nouvel algorithme de determination de politiques sous-optimales dans un graphe sequentiel. On montre enfin les applications du concept de sous-optimalite a la prise en compte d'effets indirects lies aux politiques possibles, aux choix dans l'aleatoire, a des problemes de localisation optimale d'usines... et on donne des exemples d'utilisation. (auteurs)

  1. Tractographie globale sous contraintes anatomiques

    Teillac , Achille

    2017-01-01

    This work aims at developing a method inferring white matter fibers reconstructed using a global spin-glass approach constrained by anatomical prior knowledge. Unlike usual methods building fibers independently from one another, our markovian approach reconstructs the whole tractogram in an unique process by minimizing the global energy depending on the spin glass configuration (position, orientation, length and connection(s)) and the match with the local diffusion process in order to increas...

  2. Tutoriel Android sous Android Studio

    Rodriguez , Dima

    2015-01-01

    Engineering school; Le système d’exploitation Android est actuellement l’OS le plus utilisé dans le monde faisant tourner des smartphones, tablettes, montres connectées, liseuses électroniques, télévisions interactives, et bien d'autres. C’est un système, open source qui utilise le noyau Linux. Il a été créée par Android, Inc. qui fut rachetée par Google en 2005. Le développement d’applications pour Android s’effectue en Java en utilisant des bibliothèques spécifiques. Le but de ce tutoriel e...

  3. SOUS LE PAVÉ: LA PLAGE!

    Clemmensen, Thomas Juel

    2017-01-01

    of these take their point of departure in the author’s observations of material conditions and processes on the harbor in Aarhus, which highlight the city as a geological phenomenon. But mostly the thoughts are inspired by works and ideas of artists and architects, which more or less consciously have revolved...

  4. Crack Features and Shear-Wave Splitting Associated with Fracture Extension during Hydraulic Stimulation of the Geothermal Reservoir in Soultz-sous-Forêts

    Adelinet M.

    2016-05-01

    Full Text Available The recent tomography results obtained within the scope of the Enhanced Geothermal System (EGS European Soultz project led us to revisit the meso-fracturing properties of Soultz test site. In this paper, we develop a novel approach coupling effective medium modeling and shear-wave splitting to characterize the evolution of crack properties throughout the hydraulic stimulation process. The stimulation experiment performed in 2000 consisted of 3 successive injection steps spanning over 6 days. An accurate 4-D tomographic image was first carried out based upon the travel-times measured for the induced seismicity [Calò M., Dorbath C., Cornet F.H., Cuenot N. (2011 Large-scale aseismic motion identified through 4-D P-wave tomography, Geophys. J. Int. 186, 1295-1314]. The current study shows how to take advantage of the resulting compressional wave (Calò et al., 2011 and shear-wave velocity models. These are given as input data to an anisotropic effective medium model and converted into crack properties. In short, the effective medium model aims to estimate the impact of cracks on velocities. It refers to a crack-free matrix and 2 families of penny-shaped cracks with orientations in agreement with the main observed geological features: North-South strike and dip of 65°East and 65°West [Genter A., Traineau H. (1996 Analysis of macroscopic fractures in granite in the HDR geothermal well EPS-1, Soultz-sous-Forêts, France, J. Vol. Geoth. Res. 72, 121-141], respectively. The resulting output data are the spatial distributions of crack features (lengths and apertures within the 3-D geological formation. We point out that a flow rate increase results in a crack shortening in the area imaged by both compressional and shear waves, especially in the upper part of the reservoir. Conversely, the crack length, estimated during continuous injection rate phases, is higher than during the increasing injection rate phases. A possible explanation for this is that

  5. Sous-produits de la désinfection dans l'eau potable des petits réseaux municipaux: variabilité spatio-temporelle, modélisation et stratégies de suivi

    Guilherme, Stéphanie

    2014-01-01

    Les trihalométhanes (THM) et les acides haloacétiques (AHA) constituent les seules familles réglementées de sous-produits de la désinfection (SPD). Les SPD sont des composés issus de la réaction de la matière organique naturelle présente dans l’eau et du désinfectant lors du traitement de l’eau potable. La plupart de ces composés ne sont pas réglementés, même si plusieurs études ont montré que certains SPD peuvent présenter un risque toxicologique plus important que les THM et les AHA. De nos...

  6. Méthode multi-échelle pour la modélisation du flambage des tôles minces sous contraintes résiduelles - Application au laminage

    Nakhoul , Rebecca; Montmitonnet , Pierre; Potier-Ferry , Michel

    2013-01-01

    National audience; Dans le laminage à froid, l'apparition d'une distribution hétérogène de contraintes résiduelles peut engendrer le flambage de la tôle laminée, entraînant un " défaut de planéité ". L'objectif est de définir un modèle macroscopique simple décrivant les modes et amplitudes de flambage d'une tôle sous l'effet des contraintes résiduelles issues du laminage. Le présent article présente une nouvelle méthode bi-échelle [1,2] comme une alternative du modèle de flambage développé da...

  7. Sub-critical installations for continuous evaporations of up to 200 litres/hour - description and experimental results; Installations sous-critiques d'evaporation continue jusqu'a 200 litres/heure - description et resultats experimentaux

    Auchapt, P; Bouzou, G C; Sautray, R R; Jacquotte, M C [Commissariat a l' Energie Atomique, Marcoule (France). Centre de Production de Plutonium de Marcoule

    1965-07-01

    In this report are given a detailed technological description and the test results obtained with two continuous evaporation units, one of 16 l/hr, the other of 65 l/hr. These installations are sub-critical with multiplication factors (k{sub eff}) for total reflection of 0.73 and 0.77. A third evaporator of 200 litres, also sub-critical (k{sub eff} = 0.90), is given as the limiting possible case. A description is also given of simple devices without regulator for maintaining a constant level in an extra flat, separator thus making it possible to operate without supervision in perfect safety at any concentration factor. The liberal thermal characteristics and the simple operational principles constitute a sure guarantee for operation in {alpha} and {gamma} conditions. (authors) [French] Dans ce rapport, on trouvera la description technologique detaillee et les resultats obtenus au cours des essais, de deux installations d'evaporation en continu, l'une de 16 l/h, l'autre de 65 l/h. Ces installations sont sous-critiques avec des facteurs de multiplication (k{sub eff}) en reflexion totale de 0,73 et 0,77. Un troisieme evaporateur, de 200 l/h, egalement sous-critique (k{sub eff} = 0,90), est donne comme cas limite realisable. On trouvera aussi la description de dispositifs simples, sans regulateur, permettant de garder un niveau constant dans un separateur extra-plat, ce qui permet une marche sans surveillance, en toute securite, a tous les facteurs de concentration. Les caracteristiques thermiques non poussees et les principes de fonctionnement simples, sont une garantie certaine pour l'exploitation en milieu {alpha} et {gamma}. (auteurs)

  8. Quantification de la Charge Virale et tests de résistance du VIH-1 aux ARV à partir d’échantillons DBS (Dried Blood Spots chez des patients Guinéens sous traitement antirétroviral

    Nestor Bangoura

    2015-06-01

    Full Text Available Problématique: Comme dans plusieurs pays du Sud, le suivi virologique des patients sous traitement antirétroviral (TARV en Guinée est timide voire inexistant dans certaines localités. Le but de cette étude était d’évaluer la faisabilité technique et logistique de l’utilisation des DBS dans les tests de charge virale (CV et de génotypage. Méthode: De septembre à octobre 2010, les DBS ont été préparés à partir de prélèvements sanguins de patients adultes sous TARV. Le délai d’envoi des échantillons au laboratoire de référence était de 30 jours maximum après le prélèvement et se faisait à température ambiante. La CV a été quantifiée et les échantillons de patients en échec virologique (CV ≥ 3 log10 copies/mL ont été génotypés selon le protocole de l’ANRS. L’algorithme de Stanford version 6.0.8 a été utilisé pour l’analyse et l’interprétation des mutations de résistance. Résultats: Parmi les 136 patients inclus, 129 et 7 étaient respectivement sous première et deuxième ligne de traitement avec une médiane de suivi de 35 mois [IQR: 6-108]. L’échec virologique a été noté chez 33 patients. Parmi eux, 84.8% (n = 28/33 ont bénéficié d’ungénotypage. Le taux de résistance global était de 14% (n = 19/136. Le CRF02_AG était le sous type viral le plus prévalent (82%; n = 23. Conclusion: En plus de montrer la faisabilité technique et logistique des tests de CV et de génotypage à partir des DBS, ces résultats montrent l’intérêt de leurs utilisations dans le suivi virologique des patients sous TARV. Cette étude a permis également de documenter l’échec virologique, la résistance aux ARV et la diversité génétique du VIH-1 en Guinée. Mots clés: VIH-1, Résistance aux ARV, DBS (Dried Blood Spots, Guinée Conakry, Génotypage,Charge Virale.   Quantification of Viral load and resistance tests of HIV-1 to ARVs from dried blood spotssamples in Guinean patients undergoing

  9. Impregnation of Graphite with Liquid Silicon in a Vacuum; Impregnation du graphite avec du silicium llquide sous vide; Propitka grafita kremniem v vakuume; Impregnacion de grafito con silicio liquido en el vacio

    Ivanov, V. E.; Zelenskij, V. F.; Kolendovskij, M. K.; Kolomiets, L. D.

    1963-11-15

    A study was made of the possibility of producing high thermal resistance graphite-silicon carbide materials by means of impregnating MG graphite with liquid silicon in a vacuum. An attempt is made to explain the mechanism and origins of the degradation of products during the impregnation process. On the basis of their researches the authors put forward a number of technical requirements, observance of which make it possible to produce graphite-silicon carbide materials by means of impregnation of graphite with liquid silicon-in a vacuum at temperatures of 1450 to 1600 deg. C. (author) [French] Les auteurs etudient la possibilite d'obtenir, en impregnant du graphite MG avec du silicium liquide sous vide, des materiaux au graphite, carbure et silicium resistants a la chaleur. Ils cherchent a expliquer le mecanisme et les causes de la destruction des produits au cours de l'impregnation. Se fondant sur les resultats de leurs recherches, ils enoncent un certain nombre de conditions technologiques a remplir pour obtenir les materiaux en question en impregnant le graphite de silicium liquide sous vide, a une temperature de l'ordre de 1450 a 1600 deg. C. (author) [Spanish] Los autores han estudiado la posibilidad de preparar materiales de grafito y carburo de silicio de elevada resistencia termica impregnando grafito marca MG con silicio liquido en el vacio. Proponen una explicacion del mecanismo y de las causas de la degradacion de los productos durante la impregnacion. Sobre la base de las investigaciones realizadas, los autores enumeran una serie de condiciones tecnologicas cuyo cumplimiento permite preparar piezas de grafito y carburo de silicio, impregnando el grafito con silicio liquido en el vacio a temperaturas comprendidas entre 1450 y 1600 deg. C. [Russian] V rabote izuchalas' vozmozhnost' sozdaniya grafit-karbidkremnievykh materialov s povyshennoj termostojkost'yu putem propitki grafita marki MG zhidkim kremniem v vakuume. Sdelana popytka ob{sup y

  10. Comportement des fondations et des ancrages de structures marines sous l'effet de sollicitations cycliques Behavior of Foundations and Anchors for Marine Structures under the Effect of Cyclic Stresses

    Le Tirant P.

    2006-11-01

    Full Text Available L'exploration et l'exploitation des hydrocarbures en haute mer conduisent à la mise en place d'ouvrages fixes ou flottants de dimensions de plus en plus colos sales, par des profondeurs d'eau sans cesse croissantes, atteignant actuellement 200 à 300 mètres en production, un millier de mètres en exploration. Les fondations des ouvrages pétroliers de production comprennent essentiel-lement- les pieux ou groupes de pieux, battus ou forés; - les fondations superficielles à embase poids. Le comportement des fondations ou ancrages de structures sous l'action des sollicitations cycliques est étudié, en fonction de la nature des terrains, à partir - de mesures et d'observations sur des structures réelles; d'expérimentations sur des modèles en semi-grandeur ou de simulations sur modèles réduits. Les exemples donnés situent la diversité des problèmes rencontrés pour l'instal-lation des ouvrages en haute mer et! l'ampleur des travaux nécessaires pour décrire plus correctement les phénomènes d'intéraction sols-structures mannes sous l'effet des chargements cycliques et transitoires et, par suite, mieux optimiser le dimensionnement des fondations et des ancrages. Exploration and production of hydrocarbons in the high seas lead ta the installation of fixed or floating structures having more and more colossal sizes at constantly increasing water depths which now attain 200 ta 300 meters for production and 1000 meters for exploration. The foundations of ail production structures mainly consist of - pilings or groups of pilings, either driven or drilled; superficial gravity foundations the behovior of foundations or anchors for such structures under the effect of cyclic stresses is examined as a function of the nature of formations, on the basis of - measurements and observations on actual structures, experiments with semi-full-sized models or by simulations with scale models. The examples given illustrate the diversity of the problems

  11. A fly-wheel drive with controlled-torque clutch for a reactors cooling circuit pumps; Entrainement des pompes du circuit de refrigeration d'un reacteur par volant a embrayage sous couple controle

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

    1964-10-15

    After a theoretical study on the slowing down of a centrifugal pump, the motion equations have been checked by means of experimental tests. In order to have important slowing down times (which is the case of the cooling pumps of a research reactor) it is necessary to add a fly-wheel. To prevent troubles when starting, a block pump-fly-wheel with clutch under controlled torque was developed. It is so possible to start the fly-wheel progressively without increasing too much power of the driving motor. (author) [French] Apres une etude theorique sur le mouvement de ralentissement d'une pompe centrifuge, les equations du mouvement ont ete verifiees par des essais pratiques. Pour obtenir des temps de ralentissement importants (cas des pompes de refrigeration d'un reacteur de recherche) il est necessaire d'y adjoindre un volant d'inertie. Pour eviter les inconvenients au demarrage, on a etudie un ensemble pompe-volant avec embrayage sous couple controle. Cette solution permet de lancer progressivement le volant sans augmentation appreciable de la puissance du moteur d'entrainement. (auteur)

  12. Electron bombardment fusion and continuous casting of uranium carbide. Fundamental study of the metallurgical and thermal processes; Fusion sous bombardement d'electrons et coulee continue de carbure d'uranium. Etude fondamentale des processus metallurgiques et thermiques

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

    1968-02-01

    During a pilot production run, about 1.200 kg of uranium carbide cylindrical rods were prepared by electron bombardment fusion and continuous casting in an apparatus making it possible to operate in a constant vacuum automatically. In order to make the most of the fusion technique used, it was necessary to resolve a certain number of problems involved in this production. It was found that the energy yield for the electron bombardment heating using accelerating voltages of about 10 kV was 100 per cent; about 40 per cent of the electrons are re-emitted by back-scattering. These electrons leave the surface with practically zero energy. The fusion technique leads to the elimination of the majority of the metallic impurities. In order to explain the variations in the non-metallic impurity contents the different reactions occurring in the molten uranium monocarbide have been determined. A micrographic study of the rods obtained has shown various types of crystallization depending on the rate of casting and, despite the uniaxial symmetry of the cooling, no texture has been observed, whatever the rate of fusion employed. The aspects of the fracture surfaces observed on certain rods can be explained by theory in the domain where the material is elastic. Furthermore it has been shown that a decrease in the brittleness occurs as a result of the formation of fine precipitates of the Wiedmanstatten structure type. (authors) [French] Au cours d'une fabrication pilote, environ 1 200 kg de barreaux cylindriques de carbure d'uranium ont ete prepares par fusion sous bombardement d'electrons et coulee continue dans un appareillage permettant d'operer d'une maniere automatique sous vide constant. Afin de tirer le meilleur parti possible de la technique de fusion utilisee, il importait de repondre a un certain nombre de questions soulevees par cette fabrication. Le rendement energetique du chauffage par bombardement d'electrons pour des tensions acceleratrices de l'ordre de 10 kV a ete

  13. Les littératures contemporaines sous l´angle du concept de nation = As literaturas contemporâneas sob o aspecto do conceito de nação

    Dominique Marie Philippe Geneviève Boxus

    2009-01-01

    Full Text Available Devant l´actuelle déstabilisation du concept de nation en contexte demondialisation, quelles sont la pertinence et l´actualité d´une étude des littératures contemporaines sous l´angle de la nation ? Faut-il constater l´obsolescence du concept de littérature nationale ? Pour sortir d´une impasse théorique, la perspective historique s´avèreindispensable et une étude des avatars de la nation, concept et réalité, met sur la voie d´une vision élargie où la nation est révélée comme représentation: fiction symbolique ou mythe.À côté d´un modèle mythique hégémonique privilégiant l´homogène, un autre modèle national est identifié, caractérisé par l´hétérogène et servant d´auxiliaire aux collectivités excentriques en quête d´une identification. Comme expression privilégiée du mythe de lanation, la littérature joue un rôle fondamental dans l´invention de représentations nationales inédites, ce qui justifie la pérennité d´une recherche (sociologique et/ou thématique centrée sur le littéraire contemporain (ou passé, pourvu qu´elle opère à partird´un point de vue actualisé envisagé sous l´angle de la nation.Diante da atual desestabilização do conceito de nação em contexto de globalização, quais são a pertinência e a atualidade de um estudo das literaturas contemporâneas sob o ângulo da nação? Haverá de se constatar a obsolescência do conceito de literatura nacional? Para sair de um impasse teórico, apresenta-se uma história do conceito de nação, desde suas origens no século XVIII até os dias de hoje. Abre-se caminho para uma visão ampliada da nação, ou seja, para uma definição que a revela como representação: ficção simbólica ou mito. Ao lado de um modelo mítico hegemônico que privilegia o homogêneo, um outro modelo nacional é identificado, caracterizado pelo heterogêneo e auxiliando coletividades ex-cêntricas no seu esforço de identificação. Sendo uma

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

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

    1965-07-01

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

  15. The compatibility of chromium-aluminium steels with high pressure carbon dioxid at intermediate- temperatures; Compatibilite des aciers au chrome-aluminium avec le gaz carbonique sous pression aux temperatures moyennes

    Leclercq, D; Loriers, H; David, R; Darras, E [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1964-07-01

    With a view to their use in the exchangers of nuclear reactors of the graphite-gas or heavy water-gas types, the behaviour of chromium-aluminium steels containing up to 7 per cent chromium and 1.5 per cent aluminium has been studied in the presence of high-pressure carbon dioxide at temperatures of between 400 and 700 deg. C. The two most interesting grades of steel (2 per cent Cr - 0.35 per cent Al - 0.35 per cent Mo and 7 per cent Cr - 1.5 per cent Al - 0.6 per cent Si) are still compatible with carbon dioxide up to 550 and 600 deg. C respectively. A hot dip aluminised coating considerably increases resistance to oxidation of the first grade and should make possible its use up to temperatures of at least 600 deg. C. (authors) [French] Dans l'optique de leur emploi dans les echangeurs de reacteurs nucleaires des filieres graphite-gaz ou eau lourde-gaz, le comportement en presence de gaz carbonique sous pression d'aciers au chrome-aluminium, contenant jusqu'a 7 pour cent de chrome et 1,5 pour cent d'aluminium a ete etudie entre 400 et 700 deg. C. Les deux nuances les plus interessantes (2 pour cent Cr - 0,35 pour cent Al - 0,35 pour cent Mo et 7 pour cent Cr - 1,5 pour cent Al - 0,6 pour cent Si) restent compatibles avec le gaz carbonique jusqu'a 550 et 600 deg. C respectivement. Un revetement d'aluminium, effectue par immersion dans un bain fondu, ameliore notablement la resistance a l'oxydation de la premiere et doit permettre son empioi jusqu'a 600 deg. C au moins. (auteurs)

  16. La sous-traitance au Brésil : un phénomène à la fois ancien et nouveau Subcontracting in Brazil: a phenomenon both new and old La subcontratación en Brasil : un fenómeno antiguo y nuevo a la vez

    Graça Druck

    2009-05-01

    Full Text Available L’objectif de l’article est de discuter la sous-traitance aujourd’hui au Brésil. Nous discutons dans l’article le processus de flexibilisation et de précarisation du travail au Brésil, en prenant comme objet d’étude la sous-traitance, en tant qu’une des principales politiques de gestion et d’organisation du travail dans le cadre de la restructuration productive. Nous présentons une synthèse du processus de sous-traitance observé ces dernières années dans le pays, sous ses anciennes et nouvelles modalités, et nous analysons les résultats empiriques récents sur la sous-traitance dans des entreprises industrielles à haut risque pour l’environnement et la santé des travailleurs, dans la Région Métropolitaine de Salvador/Bahia/Brésil, de même que nous indiquons les principales de formes de résistance et de contre-pouvoirs construits contre la précarisation du travail et la sous-traitance.The purpose of the article is to discuss current subcontracting in Brazil. Our study subject « subcontracting as one of the main work management and organization policies in the framework of productive restructurings » used to discuss the work flexilibization and precarization process in Brazil. We present a synthesis of the subcontracting process observed in recent years in this country, under its old and new conditions, and we analyze the recent empirical results on subcontracting in industrial enterprises at high risk to the environment and workers’ health, in the metropolitan region of Salvador/Bahia, Brazil. We also identify the main forms of resistance and the counterbalances developed against work precarization and subcontracting.El objetivo de este artículo es discutir la tercerización en el Brasil contemporáneo. Se discute el proceso de flexibilización y de precarización del trabajo en Brasil, tomando como objeto de estudio la subcontratación como una de las principales políticas de gestión y de organizaci

  17. Experimental study of columns partially filled with concrete under compressive axial loads Etude expérimentale des colonnes partiellement remplis par le béton sous charge axiale

    Achoura D.

    2012-09-01

    Full Text Available Dans cette étude, on présente les résultats expérimentaux obtenus sur des poteaux mixtes béton-acier mince réalisés par soudures. Un total de 24 profilés en acier, et en forme de I a été testé sous charge de compression uni-axiale à l’âge de 28 jours. les spécimens ont été réparties comme suit: 4 à vides, 4 partiellement remplies avec un béton ordinaire sans l’addition des connecteurs, 4 renforcés par des connecteurs de cisaillements de type cornière en U, 4 autres l’ont été avec des connecteurs de cisaillements type goujons et 8 restants ont été renforcés avec des liens transversaux d’espacement 100mm, 50mm, soudés aux bouts des ailes opposées. Les principaux paramètres étudiés sont: l’élancement du profilé, le type de connecteur de renforcement. A partir des résultats d’essais obtenus, il est confirmé que les parois minces sont plus sensibles de l’apparition au voilement et la longueur des profilés a un effet considérable sur la capacité portante et le mode de rupture. L’addition des connecteurs de renforcement a confirmé l’augmentation de la charge ultime par rapport aux profilés sans connecteurs. In the present work, results of tests conducted on thin welded steel-concrete stubs are presented. A total of 24 stubs an I steel section were tested under axial compression at 28 days after the date of casting, 4 were empty, 4 filled with normal concrete, 8 columns had shear connecters welded along the centreline of the web, and 8 columns had steel rods welded between the tips of opposing flanges on both sides of the spacing of the transverse link 100 mm and 50 mm. The main parameters studied were: the heel height, and type of connector strengthening. From the test results, it is confirmed that the thin walls are more sensitive to the appearance local buckling and the length of the profiles has a significant effect on the bearing capacity and failure mode. The bearing capacity was increased

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

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

    1965-07-01

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

  19. Kinetic Modeling of Vacuum Gas Oil Hydrotreatment using a Molecular Reconstruction Approach Modélisation cinétique de l’hydrotraitement de distillats sous vide utilisant une approche de reconstruction moléculaire

    Charon-Revellin N.

    2010-10-01

    Full Text Available Vacuum Gas Oils (VGO are heavy petroleum cuts (boiling points ranging from 350 to 550 ˚C that can be transformed into valuable fuels (gasolines, diesels by fluid catalytic cracking or hydrocracking. Prior to these conversion processes, hydrotreating is required in order to eliminate the impurities in VGOs. The hydrotreatment process enables to meet the environmental specifications (total sulfur contents and to prevent nitrogen poisoning of conversion catalysts. In order to develop a kinetic model based on an accurate VGOs molecular description, innovative analytical tools and molecular reconstruction techniques were used in this work. A lumped model using a Langmuir-Hinshelwood representation was developed for hydrodearomatization, hydrodesulfurization and hydrodenitrogenation of the VGO. This lumped model was successfully applied to the experimental feed pretreatment data and was able to predict evolution of concentration of the aromatics, nitrogen and sulfur species. Les Distillats Sous Vide (DSV sont des coupes pétrolières lourdes (gamme de températures d'ébullition 350 à 550 °C qui peuvent être valorisées en carburants (essence, gazole par craquage catalytique ou par hydrocraquage. Un hydrotraitement est requis avant ces procédés de conversion afin d'éliminer les impuretés du DSV. De cette manière, le procédé d'hydrotraitement permet d'attendre les spécifications environnementales (teneur en soufre ainsi que de prévenir l'empoisonnement par les composés azotés des catalyseurs de conversion. De manière à pouvoir développer un modèle cinétique basé sur une description moléculaire précise des DSV, des outils analytiques innovant et des techniques de reconstruction moléculaire ont été utilisés dans ce travail. Un modèle cinétique de regroupement utilisant une représentation de type Langmuir-Hinshelwood a été développé pour l'hydrodésaromatisation, l'hydrodésulfuration et l'hydrodésazotation des DSV. Ce

  20. Comportement en vapocraquage de molécules modèles et de distillats sous vide hydrotraités. Deuxième partie : pyrolyse de molécules modèles représentatives des distillats sous vide bruts et hydrotraités Steam-Cracking Behavior of Model Molecules and Hydrotreated Vacuum Distillates Part Two: Pyrolysis of Model Molecules Representative of Unprocessed and Hydrotreated Vacuum Distillates

    Freund E.

    2006-11-01

    Full Text Available La pyrolyse de molécules modèles a permis sur la base d'écarts de rendements obtenus entre le n -décane et leur mélange à 20 % avec celui-ci, l'établissement d'une échelle de potentialité de craquage présentée précédemment. L'approche des phénomènes de pyrolyse par des schémas réactionnels simplifiés est développée dans le présent article pour des molécules modèles, exemples de chaque grande famille susceptible de constituer le distillat sous vide : le perhydrophénanthrène pour les naphtènes lourds, l'octahydrophénanthrène symétrique pour les naphténoaromatiques, le naphtalène et l'alpha méthylnaphtalène pour les aromatiques méthylés ou non, le dodécylbenzène pour les aromatiques substitués par une longue chaîne aliphatique. Le cas de l'acénaphtylène a été examiné à part. On the basis of differences in yields obtained between n-decane and a 20% mixture of model molecules with n-decane, the pyrolysis of model molecules was used to determine a cracking potentiality scale that was previous described. The present article describes the approach to pyrolysis phenomena by simplified reaction mechanisms for model molecules taken from each major family liable to make up vacuum distillate, i. e. perhydrophenanthrene for heavy naphthenes, symmetrical octahydrophenanthrene for naphthenoaromatics, naphthalene and alpha-methynaphthalene for methylated or nonmethylated aromatics, dodecylbenzene for aromatics substituted for by a long aliphatic chain. The case of acenaphthylene is examined separately.

  1. Comportment of various magnesium alloys in carbon dioxide under pressure, between 400 and 600 deg; Compatibilite de divers alliages de magnesium avec le gaz carbonique sous pression entre 400 et 600 deg

    Darras, R; Baque, P; Chevilliard, C [Commissariat a l' Energie Atomique, Saclay (France).Centre d' Etudes Nucleaires

    1960-07-01

    'magnesium oxyde fritte'. Les echantillons, preleves dans des produits files, sont convenablement polis, deux etats de surface reproductibles etant realises a titre comparatif. Les essais ont ete effectues dans le gaz carbonique purifie, aux pressions de 25 et 60 atmospheres, et a des temperatures allant de 400 a 600, au moyen d'autoclaves speciaux en acier inoxydable, chauffes exterieurement. Leur duree est en general superieure a 1000 heures. Les equations des courbes d'augmentation de poids obtenues sont du type ({delta}p){sup n} = k.t (({delta}p en mg/cm{sup 2} et t en heures), l'exposant n etant voisin de 2, du moins jusqu'a 500 deg. C. En se referant a des resultats precedemment acquis quant a certains de ces materiaux exposes dans le gaz carbonique sous pression atmospherique et sous 15 atmospheres, il apparait que: 1) Pour un materiau determine: - a une pression donnee, l'oxydation augmente avec la temperature, - a une temperature donnee, l'oxydation augmente avec la pression, - dans les memes conditions de temperature et de pression, les resultats obtenus varient peu suivant les deux etats de surface etudies; 2) les alliages Mg-Zr presentent une resistance a l'oxydation amelioree par rapport au magnesium non allie; 3) l'alliage magnox est beaucoup moins avantageux dans le gaz carbonique que dans l'air, par rapport aux autres alliages. D'une facon generale, les courbes d'oxydation tendant vers un palier apres un certain temps d'exposition, la compatibilite de tous les alliages consideres avec le gaz carbonique apparait satisfaisante jusqu'a une temperature voisine de 500 deg. C, dans les conditions operatoires presentement definies; au dessus de 500 deg. C, des differences notables apparaissent entre les divers alliages, mais des phenomenes de sublimation interferent avec ceux d'oxydation, de sorte qu'un classement des divers materiaux ne peut etre base que sur leur resultante. (auteur)

  2. Radioinitiation of Chain Branched Reactions and its Sensitization; Amorcage sous rayonnement des reactions par ramification en chaine; sensibilisation du processus; Radiatsionnoe initsiirovanie tsennykh razvetvlennykh reaktsij i ego sensibilizatsiya; Radioiniciacion de reacciones en cadena ramificadas y medios para aumentar su sensibilidad

    Barelko, E V; Kartashova, L I; Komarov, P N; Proskurnin, M A [Karpov Physico-Chemical Institute, Moscow, Union of Soviet Socialist Republics (Russian Federation)

    1960-07-15

    This paper describes the results of experiments by the writers with radioinitiation of chain branched reactions of the oxidation of organic compounds. The function of radiation as an initiating agent is described with reference to the oxidation of several unsaturated hydrocarbons and butanol. The reaction is self-accelerating and proceeds spontaneously after radiation has ceased. A detailed investigation was made of a process from oxidizing benzene, which has a high radiation resistance. The writers devised a method of sensitizing the radioinitiation of the oxidation of radiation-resistant substances by chemically inert but non-radiation-resistant substances. The main quantitative features of the process for the radiooxidation of benzene are stated to be the accumulation of various reaction products, and the effect of temperature, pressure, power and radiation dosage on the process of such accumulation. Information was obtained about the mechanism of the process. The design of circulating equipment is described. (author) [French] Dans ce memoire, les auteurs presentent les resultats d'une etude consacree a l'amorcage sous rayonnement de reactions, d'oxydation des composes organiques, par ramification en chaine. Ils montrent le role des rayonnements en tant qu'agents d'amorcage de la reaction, en citant comme exemples l'oxydation de certains hydrocarbures non satures et du butanol. La reaction possede un caractere d'auto-acceleration et continue spontanement lorsque l'action des rayonnements a cesse. La reaction d'oxydation du benzene a ete etudiee en detail; elle est caracterisee par la haute stabilite de la substance vis-a-vis de l'action des rayonnements. Les auteurs formulent les principes de la sensibilisation, par l'action de substances instables vis-a-vis des rayonnements de l'amorcage sous rayonnement de la reaction d'oxydation de substances stables vis-a-vis des rayonnements et chimiquement inertes. Le memoire fournit les caracteristiques quantitatives

  3. Le CERN sous le feu des syndicats

    Lalive d'Epinay, Marc

    2002-01-01

    In order to find the money needed to complete the LHC, CERN has made savings by outsourcing some jobs, especially maintenance and cleaning. This decision has been strongly criticised by French and Swiss trade unions who claim that employees are suffering (0.5 page)

  4. 18 octobre 2013 - Le Préfet de l’Ain L. Touvet signe le livre d'or avec le Directeur général du CERN R. Heuer et le Chef du Département Technologie F. Bordry. Photo de groupe, de gauche à droite: T. Kupisz, Secrétaire général de la sous préfecture de Gex; L. Miralles, Chef du Département Infrastructure et services généraux; F. Eder, Délégué aux Relations avec les Etats hôtes; S. Donnot, Sous-préfet de Gex; L. Touvet, Préfet de l'Ain; E. Sches, Sous-préfète de Nantua; E.Gröniger-Voss, Conseiller juridique du CERN; R. Heuer, Directeur général; F. Bordry, Chef du Département Technologie et P. Bloch, Chef du Département Physique.

    Anna Pantelia

    2013-01-01

    18 octobre 2013 - Le Préfet de l’Ain L. Touvet signe le livre d'or avec le Directeur général du CERN R. Heuer et le Chef du Département Technologie F. Bordry. Photo de groupe, de gauche à droite: T. Kupisz,\tSecrétaire général de la sous préfecture de Gex; L. Miralles, Chef du Département Infrastructure et services généraux; F. Eder, Délégué aux Relations avec les Etats hôtes; S. Donnot, Sous-préfet de Gex; L. Touvet, Préfet de l'Ain; E. Sches, Sous-préfète de Nantua; E.Gröniger-Voss, Conseiller juridique du CERN; R. Heuer, Directeur général; F. Bordry, Chef du Département Technologie et P. Bloch, Chef du Département Physique.

  5. Determination of bore efficiency loss employed as powder in boral fabrication, proportionately to the dimension of grain; Determination de la reduction d'efficacite du bore ou d'un autre absorbeur employe sous forme de poudre dissemine dans un produit non absorbant, en fonction de la grosseur des grains

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

    1957-07-01

    Authors' mind was attracted by the importance of bore granulometry when employed as powder in boral fabrication. The calculation, object of this report, permits to give values for bore efficiency loss, proportionately to the dimension of spherical or ellipsoidal supposed grains. Grains to be employed should exceptionally only exceed 20 {mu} for a correspondent efficiency loss of 8 per cent about. (author) [French] L'attention des auteurs a ete attiree sur l'importance de la granulometrie du bore employe sous forme de poudre dans la fabrication du boral. Le calcul qui fait l'objet de ce rapport permet de chiffrer la perte d'efficacite du bore en fonction de la dimension des grains supposes spheriques ou ellipsoidaux. Les grains a employer ne devraient qu'exceptionnellement etre superieurs a 20 microns, ce qui correspond a une perte d'efficacite d'environ 8 pour cent. (auteur)

  6. Mike Davis, Génocides tropicaux. Catastrophes naturelles et famines coloniales (1870-1900. Aux origines du sous-développement, Paris, La Découverte, 2003, 479 p., trad. Late Victorian Holocausts, El Niño Famines and the Making of the Third World, 2001.

    Cyrille Ferraton

    2005-04-01

    Full Text Available C’est à une histoire en grande partie négligée et méconnue qu’est consacré l’ouvrage de Mike Davis Génocides tropicaux publié en 2001 sous le titre Late Victorian Holocausts, El Niño Famines and the Making of the Third World. L’Inde, la Chine, le Brésil, l’Afrique du Nord, l’Afrique australe, les Philippines, en fait, un grand nombre de pays qu’Alfred Sauvy désignera en 1952 par pays du « tiers-monde », connurent à la fin du XIXe siècle et au tout début du XXe siècle trois périodes climatique...

  7. Effect of high energy electrons on the skin and on the underlying tissues of the rabbit. A clinical and histological study; Effets des electrons de haute energie sur la peau et les tissus sous-jacents du lapin. Etude clinique et histologique

    Legeay, G; Vialettes, H; Adnet, J J; Court, L; Masse, R [Commissariat a l' Energie Atomique, Fontenay-aux-Roses (France). Centre d' Etudes Nucleaires

    1967-07-01

    The authors consider in this report the effects of high-energy electrons on rabbit teguments and on the underlying tissues after a single high dose irradiation. After briefly considering the mechanism of interaction between the electrons and matter as a function of their energy, the authors describe the dosimetry carried out, as a function of the irradiation device. The animal received surface doses of 5700 to 22100 rads in the thigh; the electron energy varied from 21 to 30 MeV. A clinical study was carried out over a period of nine months with a view to following the evolution of the damage and the functional degradation of the underlying tissues. A histological study of the induced damage was made after a second irradiation using 30 MeV electrons to produce doses of 16400 rads. Interesting observations were made concerning the damage caused to muscular and nerve tissues. (authors) [French] Les auteurs etudient, dans ce rapport, les effets des electrons de haute energie sur les teguments du lapin et les tissus sous-jacents apres une irradiation unique a dose elevee. Apres un rappel du mecanisme de l'interaction des electrons avec la matiere en fonction de leur energie, la dosimetrie realisee est exposee en fonction du dispositif d'irradiation. Les animaux ont recu, au niveau de la cuisse, des doses en surface de 5700 a 22100 rads; les energies des electrons vont de 21 a 30 MeV. Une etude clinique des lesions, observees pendant 9 mois, decrit leur evolution ainsi que les alterations fonctionnelles des tissus sous-jacents. Une etude histologique des lesions induites a ete realisee au cours d'une seconde experience pour des doses de 16400 rads avec des electrons de 30 MeV. D'interessantes observations ont ete faites concernant les lesions des tissus musculaires et nerveux. (auteurs)

  8. The Subcritical Assembly for High-Temperature Use; Assemblage Sous-Critique Pour Emploi a Haute Temperature; K voprosu o podkriticheskoj sborke dlya ispol'zovaniya pri vysokikh temperaturakh; Conjunto Subcritico para Temperatura Elevada

    Sakurai, Y.; Sekiya, T.; Suita, T. [Osaka University (Japan); Hishida, H.; Hamada, H.; Nagashima, K. [Sumitomo Atomic Energy Industries Group (Japan)

    1964-04-15

    intended to study the influence of high temperature upon the reactor parameters. (author) [French] Les assemblages sous-critiques sont a uranium naturel et a graphite. L'assemblage qui fait l'objet du memoire est caracterise par une partie a haute temperature qui peut etre placee au centre d'assemblages a basse temperature, et peut fournit des renseignements a la fois pour le futur reacteur a haute temperature refroidi par un gaz et pour la conversion directe de l'energie d'un milieu gazeux a haute temperature en electricite. En outre, il est prevu qu'il sera utilise pour renseignement. L'assemblage a ete place dans une structure de 2 x 2 x 3 m, composee de manchons en graphite de barres carrees de 10 cm de cote. La partie a haute temperature, de 1 m3, est chauffee par effet Joule et peut etre maintenue a une temperature de 2000 Degree-Sign C. Pour la partie a basse temperature, on utilise comme combustible des pastilles d'UO{sub 2} , et pour la partie , a haute temperature, des pastilles d'UC{sub 2}. Le combustible est introduit dans les manchons en graphite de barres de section carree. Les sources Am-Be de 5 c sont placees sous le socle fixe a la base des assemblages; d'autre part, les neutrons puises sont injectes dans l'assemblage a un point pris arbitrairement. La cible placee a l'extremite d'un tube branche sur un accelerateur est bombardee par un faisceau de deutons. Les connexions du dispositif de chauffage par effet Joule sont refroidies a l'eau et l'ensemble de la surface des parios de la partie a haute temperature a l'helium. Les circuits d'helium a haute temperature sont concus de maniere a servir pour les travaux de recherche relatifs a la conversion directe. Ces assemblages sont equipes d'appareils de controle et de mesure comparables a ceux dont sont dotes les petits reacteurs nucleaires. L'auteur met au point une methode experimentale de determination du laplacien du systeme; il a cherche quelle est la meilleure disposition pour la source de neutrons puises

  9. Étude expérimentale du comportement cyclique d'un acier du type 316 L sous chargement multiaxial complexe en traction-torsion-pressions interne et externe

    Bocher, L.; Delobelle, P.

    1997-09-01

    are very rich in informations and lead to classify the different types of loading, with two or three cyclic components, with respect to the observed supplementary hardening. This classification was established as follows: i) The in-phase tests with two or three components (δ = \\varphi = 0^circ); no supplementary hardening is observed. ii) The tension-pressure tests such as r_1 = 1, \\varphi = 90^circ and r_1 = - 1, \\varphi = 60^circ, the hardening is slightly inferior to that of tension-torsion tests. iii) The tension-torsion tests such as r_2 = 1 and δ = 90^circ, where a substantial additionnal hardening takes place. iv) The tension-torsion-pressure tests where the three components are strongly shifted, namely: r_1 = r_2 = 1, δ = 90^circ and \\varphi = 60^circ, and r_2 = 1, r_1 = -1, δ = 41.4^circ and \\varphi = 82.8^circ. The hardening is slightly superior to the one recorded in tension-torsion. A more thorough study is in preparation which considers all the possible combinations in tension-torsion-pressures, and will be performed on the same material. The early results tend to validate the observations presented in this article. Cette étude réside dans la détermination expérimentale du comportement à la température ambiante de l'acier inoxydable 316 L sous chargement cyclique non proportionnel en traction-torsion-pressions interne et externe. Les deux ou trois déformations sinusoïdales appliquées sont soit en phase, soit hors-phase et l'on étudie l'amplitude du durcissement supplémentaire en fonction du degré de multiaxialité. On présente quelques boucles stabilisées typiques. Par rapport au durcissement supplémentaire maximal, les différents essais peuvent être classés comme suit: essais en phase (pas de durcissement supplémentaire), essais de traction-pressions hors-phase, essais de traction-torsion hors phase et essais de traction-torsion-pressions avec déphasages conséquents.

  10. L’évolution de l’affirmative action aux États-Unis sous la présidence de George W. Bush Evolution of Affirmative Action in the United States during the Presidency of George W. Bush

    Marie-Christine Pauwels

    2010-03-01

    Full Text Available L’offensive contre l’affirmative action engagée depuis les années 1980 s’est accrue pendant les deux mandats de la présidence Bush, et l’opinion publique s’est radicalisée, percevant désormais de plus en plus fréquemment ces programmes comme une série d’avantages indûment octroyés à un certain nombre de « privilégiés ». Tout programme d’affirmative action doit désormais être étayé par des disparity studies démontrant la réalité de la discrimination, et seules des mesures très ciblées (narrowly tailored sont autorisées pour y remédier. La charge de la preuve a été en quelque sorte inversée. Mais contrairement aux idées reçues, l’affirmative action n’est pas sur le point de disparaître aux États-Unis et malgré son hostilité de principe, le gouvernement Bush n’a pris aucune mesure concrète pour démanteler ces programmes. L’affirmative action connaît aujourd’hui plusieurs transformations majeures, l’évolution la plus marquante étant l’effacement du critère ethno-racial au profit de critères plus neutres et moins idéologiquement polarisants, essentiellement d’ordre géographique et territorial. Dans l’enseignement supérieur par exemple, des procédures d’admission codées ont vu le jour pour favoriser l’accès des minorités ethniques sous-représentées aux campus d’élite, et diverses stratégies de contournement ont été mises en place dans l’adjudication des marchés publics. Ces transformations sont également intéressantes à analyser d’un point de vue transnational, puisque l’on observe une convergence croissante avec le modèle français de discrimination positive, lui aussi fondé sur le camouflage et l’euphémisation de l’identité ethno-raciale et sur une logique de territoire.This article examines the fate of affirmative action in the United States during the eight years of the Bush administration. After a brief reminder of the major landmarks

  11. Purification by high vacuum fusion and progressive solidification of uranium from electrolytic origin; Purification par fusion sous vide eleve et solidification progressive d'uranium d'origine electrolytique

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

    1964-01-15

    grain observed, so-called secondary recrystallisation. in appendix, the method for measuring the electrical resistance by induction (with direct current)is studied from the fundamental and experimental point of view. The author applied it to the particular case of uranium for measuring the low-temperature resistance of the bars from the same which solidified first to the least pure ended the ingot. (author) [French] Dans le cadre de recherches generales sur la purification de l'uranium par fusion de zone, on a entrepris de determiner le degre de purification que l'on pourrait atteindre par une simple solidification progressive a vitesse et direction soigneusement controlees d'un uranium de purete nucleaire courante. Cet uranium de purete intermediaire fournirait un materiau de depart approprie au mode de purification ultime qu'est la fusion a zone verticale, dite ''flottante''. Dans ce but, des lingots d'uranium d'origine electrolytique ont ete refondus sous vide (2 a 5 x 10{sup -6} mm) dans une longue nacelle en UO{sub 2} apres une monte lente en temperature pour eliminer le maximum de gaz et d'impuretes volatiles. Ce degazage et cette volatilisation d'impuretes sont completes par maintien prolonge a haute temperature du bais liquide. Celui-ci est ensuite solidifie d'une extremite a l'autre de la nacelle par deplacement a vitesse lente et constante du front de solidification de facon a obtenir une repartition des impuretes selon les lois etablies par PFANN. Differentes methodes experimentales ont permis de montrer que le metal solidifie en premier lieu est nettement plus pur que celui de la partie solidifie a l'extremite opposee du lingot. Le degre de purification du metal en tete du lingot a ete apprecie, soit quantitativement par mesure du rapport des resistivites electriques a la temperature ambiante et a celle de l'azote liquide, soit qualitativement par l'examen de la structure micrographique et par l'etude de la recristallisation du metal. D'une part, le metal

  12. La spirale dell’azzardo: una subcultura del gioco che “evapora” le relazioni / La spirale du jeu de hasard : une sous-culture qui empêche toute relation / The gambling: a subculture of game that “burns” the relationships

    Molin Valentina

    2011-07-01

    neutralizzazione dei possibili rinforzi negativi che provengono invece dai “non-giocatori”.Dans cet article, l’auteur analyse les caractéristiques de ce qu’elle a appelé « sous-culture des jeux de hasard », décelable dans certains milieux de loisirs et dans les sous-groupes de joueurs particulièrement « acharnés ». Parmi ces formes de sous-culture, l’article va identifier les règles et les sanctions, les valeurs, les comportements durables, la caractérisation des relations et des interactions, en concluant que ce qui est construit dans l'espace du jeu est un univers séparé, une «réalité extérieure» dans laquelle des nouvelles règles sont écrites et où les valeurs changent par rapport au «monde extérieur» . Il a également été possible de conclure que l'adhésion à l' «univers du jeu» - l'internalisation de ses normes, le partage de ses valeurs, le développement des relations en son sein - est un facteur de maintenance de la conduite du jeu, car cette adhésion permet d'envisager comme «normal» son propre comportement grâce à des réactions positives provenant des compagnons de jeu et à la neutralisation d’éventuelles réactions négatives provenant des «non joueurs».

  13. Study of atmospheric tritium transfers in lettuce: kinetic study, equilibrium and organic incorporation during a continuous atmospheric exposure; Etude des transferts du tritium atmospherique chez la laitue: Etude cinetique, etat d'equilibre et integration du tritum sous forme organique lors d'une exposition atmospherique continue

    Boyer, C.

    2009-11-30

    This thesis has explored the mechanisms of tritium 'absorption and incorporation in a human-consumed plant, lettuce (Lactuca sativa L.), due to atmospheric exposure. Foliar uptake appears to play a key role in absorption of tritium as tissue free water tritium. Whatever the development stage and the light conditions, the specific activity in tissue free water reaches that of water vapour in air in several hours. The specific activity ratio is then about 0, 4. The time to reach equilibrium in soil is over 24 hours in most cases: the specific activity ratio ranges then 0, 01 to 0, 26. Incorporation rate of tissue free water tritium as organically-bound tritium has been estimated to 0, 13 to 0, 16 % h-l in average over the growing period of the plant, but marked variations are observed during growth. In particular, a significant increase appeared at the exponential growth stage. Deposition and diffusion of tritium in soil lead to significant OBT activities in soil. Results globally indicate equilibrium between the different environmental compartments (air, soil, plant). However, some experiments have revealed high OBT concentrations regarding atmospheric level exposure and ask for a possible phenomenon of local tritium accumulation in OBT for particular conditions of exposure. (author) [French] Ce travail de these a concerne l'etude des phenomenes d'absorption et d'incorporation sous forme organique du tritium dans un vegetal de consommation courante, la laitue (Lactuca sativa L.), en reponse a une exposition atmospherique. Il apparait que la voie foliaire joue un role primordial dans l'absorption du tritium au sein de l'eau tissulaire des plants. Quels que soient le stade de developpement des plants et les conditions d'eclairement, le temps necessaire pour atteindre l'equilibre des concentrations dans l'eau libre et dans la vapeur d'eau de l'air est de plusieurs heures; le rapport des concentrations est alors de

  14. Soudage par explosion thermique sous charge de cermets poreux à base de TiC-Ni sur substrat en acier-comportement tribologique Welding of porous TiC–Ni based cermets on substrate steel by thermal explosion under load-tribological behaviour

    Lemboub Samia

    2013-11-01

    Full Text Available Dans ce travail, nous nous intéressons à l'élaboration de cermets à base de TiC-Ni par dispersion de particules de carbures, oxydes ou borures dans une matrice de nickel, grâce à la technique de l'explosion thermique sous une charge de 20 MPa. La combustion de mélanges actifs (Ti-C-Ni-An où An = Al2O3, MgO, SiC, TiB2, WC, basée sur la réaction de synthèse de TiC (ΔHf298K = −184 kJ/mole, génère des cermets complexes. Un court maintien sous charge du cermet à 1373 K, après l'explosion thermique, permet son soudage sur un substrat en acier XC55. Les cermets obtenus dans ces conditions demeurent poreux et conservent une porosité de l'ordre de 25–35 %. La densité relative du cermet, sa dureté et son comportement tribologique, dépendront de la nature de l'addition dans les mélanges de départ. Porous TiC-Ni based cermets were obtained by dispersion of carbides, oxides or borides particles in a nickel matrix thanks to the thermal explosion technique realized under a load of 20 MPa. The combustion of active mixtures (Ti-C-Ni-An where An = Al2O3, MgO, SiC, TiB2 or WC based on the titanium carbide reaction synthesis (ΔHf = −184 kJ/mol, generates porous complex cermets. After the thermal explosion, a short maintenance under load at 1373 K of the combustion product, allows at the same time the cermets welding on a carbon steel substrate. The obtained cermets under these conditions preserve a porosity of about 25–35%. The relative density, hardness and tribological behaviour of the complex cermets depend on the additions nature (An in the starting mixtures.

  15. Radioactive study of Mo{sup 93} and Mo{sup 95} levels and research of subshell effects for the shell 2d 5/2; Etude, par radioactivite des niveaux de {sup 93}Mo et de {sup 95}Mo et essai de mise en evidence de la sous-couche 2d{sub 5/2}

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

    1961-03-15

    We studied the decay schemes of Tc{sup 93} et Tc{sup 95} to determine the spins of Mo{sup 93} and M{sup 95} levels, and especially the position of the single-particle level 1g 7/2. We found a large spacing between the neutron shells 2d 5/2 and 1g 7/2 like that observed first in Mo{sup 97}. As the subshell 2d 5/2 is so far from its neighbours, we thought that subshell effects could perhaps be discovered in the systematics of separation energies and beta-decay energies. We found such effects. (author) [French] Par l'etude des schemas de desintegration de {sup 93}Tc et {sup 95}Tc, nous avons essaye de determiner les spins des niveaux de {sup 93}Mo et {sup 95}Mo et en particulier la position du niveau de particule 1g 7/2. Nous avons ainsi confirme l'ecart important entre les couches de neutrons 2d 5/2 et 1g 7/2 deja constate a propos de {sup 97}Mo. Nous avons pense que la sous-couche 2d 5/2 ainsi isolee des couches voisines pouvait, peut etre, etre mise en evidence par l'etude des systematiques d'energies de separation et d'energies de desintegration beta. Nous avons verifie qu'il en etait bien ainsi. (auteur)

  16. Emo. Origini, significati e caratteristiche della “sottocultura delle emozioni” / Emo. Origines, significations et caractéristiques de la “sous-culture des émotions” / Emo movement. Origins, meanings and characteristics of the “emotions subculture”

    Serafin G.

    2010-12-01

    Full Text Available Uno dei fenomeni giovanili, che oggi pare essere sempre più preoccupante, è quello degli “emo”. Sembra trattarsi di un movimento sottoculturale che, almeno inizialmente, muove i primi passi dal punk della fine degli anni ’70. Uno degli aspetti che caratterizza questa moderna subcultura giovanile di matrice gotica è dato da una filosofia di vita nichilista e dal ricorso all’autolesionismo. Il più delle volte si tratta di giovani e adolescenti con il bisogno di cercare una propria dimensione e che, come è facilmente intuibile dalla stessa parola “emo”, sono alla ricerca di emo-zioni.Con questo lavoro, che non pretende assolutamente di essere una esaustiva trattazione del fenomeno, si cerca di gettare alcune basi per lo studio e la comprensione di quello che sembra essere un sempre più diffuso sintomo di un disagio giovanile.L’analisi delle storie di vita di alcuni giovani emo dovrebbe, pertanto, consentire se non altro di fornire un inquadramento del movimento nei suoi tratti salienti. Un des phénomènes juvéniles qui aujourd'hui paraît être de plus en plus préoccupant est celui des « emo ». Il s’agit d'un mouvement sous-culturel qui, au moins initialement, remue les premiers pas du punk de la fin des années 70. Une philosophie de vie nihiliste et le recours à l’automutilation sont certains des aspects qui caractérisent cette sous-culture juvénile contemporaine de matrice gothique. Il s’agit le plus souvent de jeunes et d’adolescents qui ont besoin de trouver leur propre vie et qui sont – comme l’on peut deviner du même mot « emo » - à la recherche d'émo-tions.Cet article, qui ne prétend pas être une étude exhaustive du phénomène, essaye de jeter les bases pour l'analyse et la compréhension de ce qui semble être un symptôme d’un malaise juvénile de plus en plus diffusé.L'analyse des récits de vie de certains jeunes « emo » devrait, donc, permettre de fournir un encadrement du mouvement

  17. Research trends in radiobiology since 40 years. a new approach: the enzymatic repair function of DNA, internal factor in evolution of biological systems under irradiation; Etude des tendances des recherches en radiologie depuis 40 ans. Une nouvelle voie de recherche: la fonction de reparation enzymatique de l'ADN, facteur interne d'evolution des systemes biologiques sous rayonnement

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

    1968-07-01

    'on croyait encore que les effets des rayonnements sur les systemes vivants etaient des effets directs, immediats, irreparables et definitifs. Depuis lors, on s'est rendu compte que les radiolesions pouvaient resulter d'effets indirects, etre tardives, reparables, et le plus souvent modifiables par des traitements chimiques ou biochimiques ad hoc. Cependant, la percee decisive en radiobiologie se situe entre 1962 et 1964, avec la decouverte que la cellule possede un mecanisme de defense active vis-a-vis de tout ce qui peut porter atteinte a l'integrite du patrimoine genetique inscrit dans la structure meme de l'ADN. L'existence d'une quatrieme fonction de l'ADN, celle d'auto-reparation, par voie enzymatique sous controle genetique, apporte enfin a la radiobiologie la base biologique moleculaire qui lui manquait pour sortir de la nuit 'phenomenologique' ou elle s'etait enfoncee apres l'abandon de la generalisation de la theorie de Lea, faute de preuve experimentale. Dans la seconde partie, cette fois prospective, de l'etude l'auteur tente une synthese elargie en considerant le role que peut jouer cette fonction de reparation de l'ADN non seulement du point de vue de la survie des systemes biologiques irradies en presence ou non d'agents modificateurs de dose ou mutagenes, mais aussi de celui de l'evolution naturelle ou artificielle de ces systemes sous rayonnement. Les donnees les plus recentes de la litterature sont en accord avec ce qui ne constitue encore qu'une hypothese generale de recherche. Des travaux portant sur les caracteres phenotypiques et genotypiques lies a l'acquisition de radioresistance gamma et UV, chez 'Escherichia coli K12', ont ete entrepris par l'auteur, en collaboration avec O. Tremeau en vue d'apporter une contribution experimentale nouvelle a cet egard. (auteur)

  18. Comportement en vapocraquage de molécules modèles et de distillats sous vide hydrotraités. Première partie : potentialité de craquage, réacteur à profil de température rectangulaire et à court temps de séjour Steam-Cracking Behavior of Model Molecules and Hydrotreated Vacuum Distillates

    Berthelin M.

    2006-11-01

    Full Text Available Dans le cadre de la valorisation des coupes lourdes par vapocraquage, des distillats sous vide plus ou moins hydrotraités et des molécules modèles ont été pyrolysés. Cette étude a été réalisée sur un micropilote dont la partie réactionnelle est chauffée entre 680 et 860°C, par induction électromagnétique haute fréquence; le débit total peut varier de 60 à 800 g/h avec une perte de charge inférieure à 0,3 bar. Deux réacteurs tubulaires spiralés de rapport surface/volume allant jusqu'à 2000 m-1 permettent d'atteindre des temps de séjour de 10 à 400 millisecondes. Un indice quantifiant l'aptitude de chaque molécule à produire de l'éthylène, du propylène et des composés lourds, a permis l'établissement d'une échelle de potentialité de craquage, permettant d'orienter les performances d'un catalyseur de prétraitement : optimisation de la consommation d'hydrogène, meilleure valorisation des charges lourdes lors du vapocraquage. Grâce au profil de température rectangulaire du micropilote, des gains très importants de rendements d'éthylène et une production très faible d'asphaltènes ont été mis en évidence par pyrolyse de distillats sous vide hydrotraités. L'importance primordiale de la température dans le couple température-temps de séjour a été confirmée. Within the framework of the upgrading of heavy cuts for steam cracking, more or less hydrotreated vacuum distillates and model molecules were pyrolyzed. This research was done in a micropilot plant in which the reaction section was heated to between 680 and 860°C by high-frequency electromagnetic induction. The total flow rate can vary from 60 to 800 g/h with a pressure drop of less than 0. 3 bar. Two spiral tubular reactors with a high surface/volume ratio of up to 2000 m-1 enable residence times of 10 to 400 milliseconds to be obtained. An index quantifying the capacity of each molecule to produce ethylene, propylene and heavy compounds was used

  19. Geopressure and Trap Integrity Predictions from 3-D Seismic Data: Case Study of the Greater Ughelli Depobelt, Niger Delta Pressions de pores et prévisions de l’intégrité des couvertures à partir de données sismiques 3D : le cas du grand sous-bassin d’Ughelli, Delta du Niger

    Opara A.I.

    2012-05-01

    Full Text Available The deep drilling campaign in the Niger Delta has demonstrated the need for a detailed geopressure and trap integrity (drilling margin analysis as an integral and required step in prospect appraisal. Pre-drill pore pressure prediction from 3-D seismic data was carried out in the Greater Ughelli depobelt, Niger Delta basin to predict subsurface pressure regimes and further applied in the determination of hydrocarbon column height, reservoir continuity, fault seal and trap integrity. Results revealed that geopressured sedimentary formations are common within the more prolific deeper hydrocarbon reserves in the Niger Delta basin. The depth to top of mild geopressure (0.60 psi/ft ranges from about 10 000 ftss to over 30 000 ftss. The distribution of geopressures shows a well defined trend with depth to top of geopressures increasing towards the central part of the basin. This variation in the depth of top of geopressures in the area is believed to be related to faulting and shale diapirism, with top of geopressures becoming shallow with shale diapirism and deep with sedimentation. Post-depositional faulting is believed to have controlled the configuration of the geopressure surface and has played later roles in modifying the present day depth to top of geopressures. In general, geopressure in this area is often associated with simple rollover structures bounded by growth faults, especially at the hanging walls, while hydrostatic pressures were observed in areas with k-faults and collapsed crested structures. Les campagnes de forages profonds dans le delta du Niger ont démontré la nécessité d’une analyse détaillée des surpressions et de l’intégrité des structures pour évaluer correctement les prospects. La prédiction des pressions interstitielles a pu être réalisée ici avant forage à partir de données sismiques 3-D du grand sous-bassin d’Ughelli, dans le delta du Niger. Ce travail a permis de prévoir les régimes de pression du

  20. Disposal of Radioactive Waste in the Subsurface of the Federal Republic of Germany: Geological and Hydro-Geological Problems; Elimination des Dechets Radioactifs dans le Sous-Sol de la Republique Federale d'Allemagne: Problemes Geologiques et Hydrogeologiques; 041f 041e 0414 ; Evacuacion de Desechos Radiactivos en el Subsuelo de la Republica Federal de Alemania Problemas Geologicos e Hidrogeologicos

    Wagner, R.; Richter, W. [Bundesanstalt fuer Bodenforschung, Hannover (Germany)

    1960-07-01

    The geological and hydrogeological problems related to the subsurface disposal of radioactive wastes in the Federal Republic of Germany are outlined. Special consideration is given to the possibility of storing solid and liquid wastes in the salt-domes widespread in the north-west, and of injecting liquid waste into deep reservoirs containing briny water and located in favourable geologic structures. (author) [French] Les auteurs decrivent les problemes geologiques et hydrogeologiques que pose, dans la Republique federale d'Allemagne, l'elimination des dechets radioactifs dans le sous-sol. Ils examinent notamment la possibilite d'emmagasiner des dechets solides et liquides dans les salines, qui abondent dans la partie nord-ouest et d'injecter des dechets liquides dans de profonds reservoirs d'eau saline, situes dans des formations geologiques presentant des conditions favorables. (author) [Spanish] Los autores exponen los problemas geologicos e hidrogeologicos que plantea la evacuacion de desechos radiactivos en el subsuelo de la Republica Federal de Alemania. Examinan sobre todo la posibilidad de almacenar desechos solidos y liquidos en los domos de sal, muy abundantes en el noroeste del pais, y de inyectar desechos liquidos en depositos profundos de agua salobre situados en estructuras geologicas que presentan condiciones favorables. (author) [Russian] Privoditsja opisanie geologicheskih i gidrogeologicheskih problem, svjazannyh s podzemnym udaleniem radioaktivnyh othodov v Federal'noj Respublike Germanii. Osoboe vnimanie udeljaetsja vozmozhnosti skladirovanija tverdyh i zhidkih othodov v soljanyh kupolah, imejushhihsja v bol'shom kolichestve v severo- zapadnoj chasti Germanii, i zahoronenija zhidkih othodov v glubokie rezervuary, soderzhashhie solenye vody i raspolozhennye v podhodjashhih geologicheskih strukturah. (author)

  1. Theoretical aspects of neutron interaction: part 1 - interaction programme for ibm 7094, part 2 - the shielding sub-programme, part 3 - listing of the programme; Aspects theoriques de l'interaction neutronique: annexe 1 - programme interaction pour ibm 7094 - annexe 2 - sous programme ombre - annexe 3 - liste du programme

    Moret-Bailly, J; Penet, F; Spinelli, J C [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1965-07-01

    Part I. Methods are described for obtaining the equations for a system of elements containing fissile matter: a) by using the balance after fission, b) by using the balance before fission, c) by the evolution equations. All these methods lead to equivalent matrices whose greatest proper value is the multiplication coefficient for the system K. It is shown how to calculate K. From this it is possible to deduce the rules which generalize the criterion for the bounded solid angle. An IBM 7094 programme applies this theory to the calculation of the installations made up of a maximum of 500 elements. It calculates the effective values of K, the leaks, the solid angles and then K. Part. II. This sub-programme calculates the shielding between the elements. (authors) [French] Sommaire, - Annexe I. On expose les methodes permettant d'obtenir les equations d'un systeme d'elements contenant de la matiere fissile: a) par le bilan apres fission, b) par le bilan avant fission, c) par les equations d'evolution. Toutes ces methodes conduisent a des matrices equivalentes dont la plus grande valeur propre est le coefficient de multiplication de l'ensemble K. On montre comment K se calcule. On en deduit des regles qui generalisent le critere de l'angle solide limite. Un programme pour IBM 7094 applique cette theorie au calcul des installations comportant au maximum 500 elements. II calcule les k effectifs, les fuites, les angles solides puis K. Annexe II. Ce sous-programme calcule les ombres entre les elements. (auteurs)

  2. Construction, Cost and Use of an Enriched Uranium, Light-Water Subcritical Assembly; Assemblage Sous-Critique a Uranium Enrichi et Eau Legere; Realisation, Cout et Application; Realizatsiya i stoimost' podkriticheskoj sborki na obogashchennom urane i legkoj vode; Construccion, Coste y Aplicacion de un Conjunto Subcritico de Uranio Enriquecido

    Vittoz, B.; Berthet, P.; Gavin, P.; Mandrin, C.; Robert, P.; Thurnheer, J. [Ecole Polytechnique de l' Universite de Lausanne (Switzerland)

    1964-02-15

    Designed for the experimental investigation of multiplying lattices, the Lausanne subcritical assembly is also used for teaching purposes. It is extremely versatile. The authors explain why the Nuclear Engineering Laboratory of the Ecole Polytechnique, University of Lausanne, decided to construct a subcritical assembly, relying as far as possible on its own resources, and why a slightly enriched uranium, light-water lattice was selected. The construction and arrangements are such that the lattice and neutron input parameters can be varied quickly and easily. 1. The uranium rods are vertically suspended and each suspension point has two degrees of freedom and can be continuously varied. Hence the lattice spacing, for example, can also be continuously varied. 2. The neutron input is provided by five Pu-Be sources placed in a graphite base. The spacing of these sources can also be continuously regulated. The paper discusses the safety problems the facility involves because of the fact that the reactivity can vary a great deal from one configuration to the other. It also explains the general construction and operational costs. The facility is used, inter alia, to study a non-periodic lattice with a view to obtaining a uniform flux. For this purpose the heterogeneous theory developed by Feinberg and Horning is used. A lattice in which the rods are identically arranged in non-equidistant, parallel n-planes is first considered. Each plane is a fast- neutron source and an absorber of thermal neutrons. Outside these planes, two-group diffusion equations are used. If the characteristics of a single plane are known the neutron flux for the n- planes can be forecast. These characteristics are determined experimentally, with due regard to the vertical variation of the neutron flux. The role played by the distance between the rods in a given plane is also investigated. (author) [French] Destine a l'etude experimentale des reseaux ienultiplicateurs, l'assemblage sous-critique de

  3. Present Status of Nitrogen Fixation by Reactor Radiation; Etat Actuel des Recherches sur l'oxydation directe de l'azote sous irradiation dans des reacteurs; Sovremennoe sostoyani opytov po okisleniyu azota izlucheniem iz reaktorov; Estado actual de las investigaciones sobre fijacion del nitrogeno por irradiacion en reactores

    Harteck, P; Dondes, S [Rensselaer Polytechnic Institute, Troy, NY (United States)

    1960-07-15

    'oxydation directe de l'azote sous irradiation, entreprises depuis plusieurs annees par le Rensselaer Polytechnic Institute et le Brookhaven National Laboratory, utilisent directement les particules de recul de fission comme rayonnements ionisants, au moyen de la dispersion d'uranium-235 dans des fibres de verre de cinq microns de diametre environ. Les auteurs ont determine les effets de la temperature, de la pression et du rapport azote/oxygene sur la valeur de G pour l'oxydation de l'azote et ont publie le compte rendu de leurs travaux. Ils en donnent un bref apercu. Les recherches en question ont ete effectuees avec des systemes statiques; plus recemment des systemes statiques et des systemes a circulation ont ete utilises a la fois. Avec les systemes statiques, les auteurs se sont surtout attaches a etudier l'effet de l'intensite des rayonnements, notamment sur la cinetique d'equilibre sous irradiation. Ils ont constate que dans des melanges ou le rapport azote/oxygene est de 4 a 1 et de 2 a 1 N0{sub 2} et N{sub 2}0 se forment jusqu'a epuisement de tout l'oxygene present. Un systeme a circulation continue (cycling) fonctionne maintenant dans une boucle a l'interieur du reacteur de Brookhaven. Les auteurs fournissent sur les effets de la temperature, de la pression, du rapport azote/oxygene et de l'intensite des rayonnements des donnees que l'on pourra utiliser pour etablir un projet de reacteur de chimie nucleaire. Le systeme actuel fonctionne sous 10 atmospheres et a 150{sup o}C. La temperature est fonction de l'energie de fission liberee dans les fibres de verre et de la resistance thermique du circuit. Une autre boucle, qui doit fonctionner sous 50 - 75 atmospheres et a 600{sup o} C, est en construction. Il est possible, grace a ces boucles, d'etudier les caracteristiques d'un systeme continu, y compris le comportement des produits de fission liberes dans le courant, gazeux. Les auteurs distinguent trois stades dans la cinetique complexe de l'oxydation de l'azote: reactions

  4. Organisation of biological research carried out in the United States by the A.E.C. or under her contract (1960); Organisation des recherches biologiques menees aux Etats-Unis par l'A.E.C. ou sous son egide. Compte-rendu sommaire d'une mission d'etude (1960)

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

    1960-07-01

    This report is based on information gathered in the course of a trip to the United States, in November and December 1958 which consisted chiefly of visits to the main biological and medical research laboratories and discussions with the heads of these establishments. A description is given of the general organisation of the Atomic Energy Commission's Division of Biology and Medicine, and of the distribution of responsibility for radiation protection work and for biological, medical and agricultural research amongst the various Services attached to it; this is followed by a more detailed account of the activities carried on in this field at the great national laboratories. Finally, the systems of collaboration set up with external research organisations in the form of research contracts are examined, together with the substantial help provided by the A.E.C. for biological, medical and agricultural research in general, owing to a systematic policy of subsidising the distribution of radioisotopes for this purpose. (author) [French] Le present rapport a ete etabli sur la base des renseignements recueillis au cours d'un voyage d'etude aux Etats-Unis, en novembre et decembre 1958, comportant notamment la visite des principaux laboratoires de recherche biologique et medicale et des entretiens avec les principaux responsables de ces laboratoires. Apres une description de l'organisation generale de la 'Division of Biology and Medicine' de l'Atomic Energy Commission et de la repartition entre les divers Services qui lui sont rattaches des responsabilites concernant la protection contre les radiations et la Recherche biologique, medicale et agronomique, des indications plus detaillees sont donnees au sujet des activites poursuivies dans ce domaine au sein des grands laboratoires nationaux. Sont examinees enfin, l'importance et les modalites de la collaboration instituee avec les Organismes de Recherche exterieurs sous la forme de contrats de recherche ainsi que l

  5. Organisation of biological research carried out in the United States by the A.E.C. or under her contract (1960); Organisation des recherches biologiques menees aux Etats-Unis par l'A.E.C. ou sous son egide. Compte-rendu sommaire d'une mission d'etude (1960)

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

    1960-07-01

    This report is based on information gathered in the course of a trip to the United States, in November and December 1958 which consisted chiefly of visits to the main biological and medical research laboratories and discussions with the heads of these establishments. A description is given of the general organisation of the Atomic Energy Commission's Division of Biology and Medicine, and of the distribution of responsibility for radiation protection work and for biological, medical and agricultural research amongst the various Services attached to it; this is followed by a more detailed account of the activities carried on in this field at the great national laboratories. Finally, the systems of collaboration set up with external research organisations in the form of research contracts are examined, together with the substantial help provided by the A.E.C. for biological, medical and agricultural research in general, owing to a systematic policy of subsidising the distribution of radioisotopes for this purpose. (author) [French] Le present rapport a ete etabli sur la base des renseignements recueillis au cours d'un voyage d'etude aux Etats-Unis, en novembre et decembre 1958, comportant notamment la visite des principaux laboratoires de recherche biologique et medicale et des entretiens avec les principaux responsables de ces laboratoires. Apres une description de l'organisation generale de la 'Division of Biology and Medicine' de l'Atomic Energy Commission et de la repartition entre les divers Services qui lui sont rattaches des responsabilites concernant la protection contre les radiations et la Recherche biologique, medicale et agronomique, des indications plus detaillees sont donnees au sujet des activites poursuivies dans ce domaine au sein des grands laboratoires nationaux. Sont examinees enfin, l'importance et les modalites de la collaboration instituee avec les Organismes de Recherche exterieurs sous la forme de

  6. Research trends in radiobiology since 40 years. a new approach: the enzymatic repair function of DNA, internal factor in evolution of biological systems under irradiation; Etude des tendances des recherches en radiologie depuis 40 ans. Une nouvelle voie de recherche: la fonction de reparation enzymatique de l'ADN, facteur interne d'evolution des systemes biologiques sous rayonnement

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

    1968-07-01

    . Il y a moins d'une generation, l'on croyait encore que les effets des rayonnements sur les systemes vivants etaient des effets directs, immediats, irreparables et definitifs. Depuis lors, on s'est rendu compte que les radiolesions pouvaient resulter d'effets indirects, etre tardives, reparables, et le plus souvent modifiables par des traitements chimiques ou biochimiques ad hoc. Cependant, la percee decisive en radiobiologie se situe entre 1962 et 1964, avec la decouverte que la cellule possede un mecanisme de defense active vis-a-vis de tout ce qui peut porter atteinte a l'integrite du patrimoine genetique inscrit dans la structure meme de l'ADN. L'existence d'une quatrieme fonction de l'ADN, celle d'auto-reparation, par voie enzymatique sous controle genetique, apporte enfin a la radiobiologie la base biologique moleculaire qui lui manquait pour sortir de la nuit 'phenomenologique' ou elle s'etait enfoncee apres l'abandon de la generalisation de la theorie de Lea, faute de preuve experimentale. Dans la seconde partie, cette fois prospective, de l'etude l'auteur tente une synthese elargie en considerant le role que peut jouer cette fonction de reparation de l'ADN non seulement du point de vue de la survie des systemes biologiques irradies en presence ou non d'agents modificateurs de dose ou mutagenes, mais aussi de celui de l'evolution naturelle ou artificielle de ces systemes sous rayonnement. Les donnees les plus recentes de la litterature sont en accord avec ce qui ne constitue encore qu'une hypothese generale de recherche. Des travaux portant sur les caracteres phenotypiques et genotypiques lies a l'acquisition de radioresistance gamma et UV, chez 'Escherichia coli K12', ont ete entrepris par l'auteur, en collaboration avec O. Tremeau en vue d'apporter une contribution experimentale nouvelle a cet egard. (auteur)

  7. Sous type rare du cancer de prostate: Le carcinome sarcomatoide

    A. Qarro

    est essentiellement chirurgical qui peut aller de la simple résection de la prostate jusqu'à l'exentération pelvienne associée ou non à la chimiothérapie ou à la radiothérapie. Le pronostic est très mauvais avec 20% de risque de décès la première année qui suit le diagnostic. Nous rapportons une observation d'un patient.

  8. Echanges thermiques dans un four à combustible eau sous ...

    Belonging to the class of the diffusive phenomena, these thermal transfers were explained using mathematical techniques among which transformations of Fourier and Laplace.. Concurrently to these theoretical aspects, the phenomena of transfers of heat intervene in an eminent way in the industrial activities and the life of ...

  9. Le CERN sous haute sécurité

    Scappaticci, Bruno

    2008-01-01

    1500 prestigious guests came to participate to the LHC inauguration on last Tuedday, among which the Swiss President and the French Prime Minister François Fillon. Picked unities of the polices (Swiss an French) were on a war-footing.. (2 pages)

  10. Les agendas 21 locaux : quels apports sous quelles latitudes ?

    Cyria Emelianoff

    2005-05-01

    Full Text Available Since the Rio conference, several thousands local agendas 21 have assisted the penetration of the concept of sustainable development at the local level. This article presents a synthesis of the approaches employed by local authorities in 9 European countries, with an emphasis on the benefits and limitations presented by the local agendas 21 in place. We characterised the specificities of French local authorities and determined the geographical dimensions of the mobilisation in favour of local agendas 21.

  11. De vieilles obsessions sous des habits neufs ?

    Louis Quéré

    2011-10-01

    Full Text Available Cet article fait le tri dans le texte de Laurence Kaufmann et Laurent Cordonier entre ce qui paraît et ce qui ne paraît pas plausible dans leurs conjectures. Il spécifie à quelles conditions on peut admettre l'hypothèse du « cerveau social ». Il est par contre plus critique à l'égard de l'idée d'une « régulation neuroendocrinienne du lien social ». L'argument est que les auteurs n'estiment pas correctement les possibilités et les limites des explications neuroscientifiques des conduites humaines et des relations sociales. Enfin l'article confronte la forme de naturalisme social défendue par les auteurs à celle de la tradition pragmatiste (John Dewey et George Herbert Mead et s'appuie sur la seconde pour faire ressortir le caractère problématique de la première.A new look for old obsessions?This paper tries to sift out the plausible in what Laurence Kaufmann and Laurent Cordonier tell in their article. It specifies some conditions for the acceptation of their surmise about the « social brain ». It criticizes much more their speculations about a « neuroendocrinous regulation of the social bond ». It argues that the authors don't estimate properly the capacities and the limits of the neuroscientific explanations of human conduct and social relations. Finally, it compares the version of social naturalism assumed by the authors with the pragmatist tradition's one (John Dewey and George Herbert Mead and uses this last to show the problematic character of the first.¿Nuevas apariencias de añejas obsesiones?El autor pasa por la criba el texto de Laurence Kaufman y Laurent Cordonier y distingue entre lo que parece plausible y lo que no lo es. Específica bajo qué condiciones puede admitirse la hipótesis de un « cerebro social ». Es mucho más crítico con respecto a la « regulación neuro-endocrina de los lazos sociales ». Estos autores no analizan correctamente las posibilidades y los límites de las explicaciones neuro-científicas del comportamiento humano y de las relaciones sociales. El autor también confronta la forma de naturalismo social defendida por los autores con la de la tradición pragmatista (John Dewey y George Herbert Mead apoyándose en este último para resaltar el carácter problemático de la primera.

  12. Les formes psychiatriques des hematomes sous-duraux chroniques ...

    Methods: This was a retrospective study of 26 cases of chronic subdural hematoma with psychiatric disorders admitted in neurology, neurosurgery and psychiatry of Hôpital Général de Grand Yoff and Fann's CHU of Dakar (Senegal) between 2001 in 2009. Results: The mean age of patients was 80.6 years. No patient had a ...

  13. Les objets sous contrainte. Gages, saisies, confiscation, vol, pillage, recel…

    Laurent Feller

    2009-09-01

    Full Text Available Cette table ronde s’inscrit dans le cadre d’une réflexion menée sur la valeur des choses au Moyen Âge, c’est-à-dire sur les conditions empiriques et théoriques de l’évaluation ; un groupe de travail conjoint du LAMOP (UMR 8589, Paris 1-CNRS et du CSIC de Madrid organise une série de tables rondes. La première s’est tenue à Madrid en novembre 2008 et a eu comme thème : « Circulation et remploi des objets au Moyen Âge ».Les objets circulent parfois malgré la volonté de leurs propriétaires, en ...

  14. Carcinome adenoide kystique sous-glottique | Gassab | Journal ...

    Case report: A 75-year-old man, presented with a laryngeal dyspnea. The computed tomography of the larynx showed a posterior subglottic tumor. The panendoscopy revealed a large nonulcerated submucosal tumor in the posterior wall of the subglottic area. Biopsies made the diagnosis of laryngeal ACC. The patient had ...

  15. Pia Petersen sous le signe de don Quichotte

    Esther Bautista Naranjo

    2013-04-01

    Full Text Available This interview has been motivated by the Cervantean intertextuality of Pia Petersen’s (a French-speaking Danish author last novel, Le Chien de don Quichotte (2012. Departing from the values that the writer attributes to Cervantes’ work, I try to establish a connection with a specific critical trend in order to test, later on, to which extent this approach is used by the author to create a series of characters placed under the sign of don Quixote. Finally, I evaluate her novel’s relation with contemporary reality.

  16. Machine for extrusion under vacuum; Machine de fluage sous vide

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

    1958-07-01

    In a study of the behaviour of easily oxidised metals during the extrusion process, it is first necessary to find an effective mean of fighting corrosion, since this, even when barely detectable, has an important influence on the validity of the results recorded. The neatest and also the most efficient of all the methods tried consists in creating a vacuum around the test piece. Working on this principle, and at the same time respecting the conventional rules for extrusion tests (loading the sample after stabilisation at the testing temperature, differential measurements of lengthening, etc.) we found it necessary to construct an original machine. (author) [French] L'etude du comportement au fluage des materiaux facilement oxydables exige, en premier lieu, une lutte efficace contre la corrosion qui, meme a peine decelable, prend une part preponderante quant a la validite des resultats enregistres. La solution la plus elegante, et, a vrai dire, la plus energique parmi toutes les methodes essayees, consiste a realiser le vide autour de l'eprouvette d'essai. Partant de ce principe, et pour sauvegarder les regles classiques de l'essai de fluage (mise en charge de l'eprouvette apres stabilisation en temperature d'essai, mesures differentielles des allongements, etc.) nous nous sommes trouves dans la necessite de construire une machine inedite. (auteur)

  17. Machine for extrusion under vacuum; Machine de fluage sous vide

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

    1958-07-01

    In a study of the behaviour of easily oxidised metals during the extrusion process, it is first necessary to find an effective mean of fighting corrosion, since this, even when barely detectable, has an important influence on the validity of the results recorded. The neatest and also the most efficient of all the methods tried consists in creating a vacuum around the test piece. Working on this principle, and at the same time respecting the conventional rules for extrusion tests (loading the sample after stabilisation at the testing temperature, differential measurements of lengthening, etc.) we found it necessary to construct an original machine. (author) [French] L'etude du comportement au fluage des materiaux facilement oxydables exige, en premier lieu, une lutte efficace contre la corrosion qui, meme a peine decelable, prend une part preponderante quant a la validite des resultats enregistres. La solution la plus elegante, et, a vrai dire, la plus energique parmi toutes les methodes essayees, consiste a realiser le vide autour de l'eprouvette d'essai. Partant de ce principe, et pour sauvegarder les regles classiques de l'essai de fluage (mise en charge de l'eprouvette apres stabilisation en temperature d'essai, mesures differentielles des allongements, etc.) nous nous sommes trouves dans la necessite de construire une machine inedite. (auteur)

  18. Irradiation damage 'displacement zone'; Dommages sous irradiation zone de deplacements

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

    1969-07-01

    It is well known that a charged particle (ion, primary atom, etc...) moving in a solid slows down and can cause a cascade of displacements of the atoms in the solid. A study is made here of the extent to which the cascade is made up, or not, of independent collisions, as a function of the energy of the initial charged particle. When the distance between the collisions is small, these latter are no longer independent; the cascade, which then has to be considered as a whole, perturbs and locates, in the irradiated solid , a zone which has been named a 'displacement zone'. It is shown that the proportion of displacement zones increases with increasing atom size (high atomic number Z), with decreasing atomic distance D in the substance considered and with decreasing energy of the ion undergoing the slowing down process (although always remaining above a few hundred eV). The proportions obtained are higher than those corresponding to the calculations of J. A. Brinkman [3]. An interatomic potential required for this work has also been determined. (author) [French] On sait qu'une particule chargee (ions, atomes primaires, etc...) en mouvement dans un solide se ralentit, avec eventuellement deplacement en cascade d'atomes du solide. On etudie ici dans quelle proportion, en fonction de l'energie de la particule chargee initiale, la cascade est constituee, ou non, de 'chocs independants'. Lorsque la distance entre chocs est petite, ceux-ci ne sont plus independants; la cascade, qui doit alors etre consideree dans son ensemble, perturbe et definit dans le solide irradie, une zone qu'on a appele zone de deplacements. On montre que la proportion de zones de deplacements est d'autant plus grande que les atomes sont gros (nombre atomique Z grand), que la distance interatomique D est petite dans le corps considere, et que l'energie de l'ion en ralentissement est petite (tout en restant superieure a quelques centaines d'eV). Les proportions obtenues sont superieures a celles qui correspondraient aux calculs de J. A. BRINKMAN [3], On determine d'autre part un potentiel interatomique, necessaire a cette etude. (auteur)

  19. Emissions under reinforced supervision; Des emissions sous surveillance renforcee

    Remoue, A

    2009-11-15

    Despite some enforcement difficulties, the Integrated Pollution Prevention and Control (IPPC) European directive on the integrated approach of pollution is going to harden. The new version, which will be presented on second lecture at the Parliament in the beginning of 2010 will oblige industries to opt for the best available technologies. In Europe, 55000 sites are concerned by the IPPC directive, among which 6760 are in France. Today, about 1650 French sites are not in order with this directive. (J.S.)

  20. Comparison of fission probabilities with emission of long range particles under the action of slow and fast neutrons on various materials; Probabilites comparees de fission avec emission de particules de long parcours pour divers materiaux sous l'action des neutrons lents et rapides

    Netter, F; Faraggi, H; Garin-Bonnet, A; Julien, J; Corge, C [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires; Turkiewicz, J [Institut de Recherches Nucleaire de Varsovie (Poland)

    1958-07-01

    parcours, sous l'action de neutrons de diverses energies: neutrons thermiques, neutrons de pile, neutrons produits avec l'accelerateur Van de Graaff par la reaction des protons sur le tritium. Les mesures sont effectuees: 1) a l'aide de plaques photographiques, en soumettant a l'action des neutrons une couche de matiere fissile, accolee contre une emulsion nucleaire Ilford de 100 microns; une feuille d'etain appliquee entre la plaque et la couche arrete les {alpha} et les fragments de fission. On distingue dans l'emulsion par un developpement approprie les trajectoires de particules de long parcours des trajectoires de protons de recul provenant soit des neutrons de fission, soit des neutrons primaires rapides. La frequence comparee des trajectoires des particules de long parcours et des reculs dus aux neutrons de fission fournit une mesure de la section efficace de fission avec emission de particules de long parcours relativement au produit de la section efficace de fission par le nombre moyen de neutrons emis par fission. Des precautions sont prises peur eliminer le role des neutrons thermiques dans les mesures par neutrons rapides. 2) a l'aide d'un systeme de chambre d'ionisation et compteur proportionnel, on mesure le taux de coincidence entre les impulsions produites par la particule de long parcours et celles produites par un des fragments de fission, relativement au taux de comptage des fragments de fission. (auteur)

  1. Pulsed Source Measurements on a Uranium-Water Subcritical Assembly; Mesures Faites sur un Assemblage Sous- Critique Uranium-Eau Ordinaire a l'Aide d'une Source Pulsee; Izmereniya s pomoshch'yu istochnikov impul'snykh nejtronov na urano-vodnoi podkriticheskoi sborke; Mediciones con Fuentes Pulsantes en un Conjunto Subcritico Uranio-Agua

    Gibson, I. H.; Walker, J. [Department of Physics, University of Birmingham, Birmingham (United Kingdom)

    1964-02-15

    An unreflected assembly of natural uranium and light water has been used in conjunction with a pulsed source of neutrons for decay-time measurements at different bucklings. Four different lattice pitches over the range 3.94 cm to 5.08 cm were obtained by using different pairs of accurately machined lattice plates and in each case the uranium was in the form of bars 109.8 cm long and 3.0 cm diameter. The fuel- was mounted horizontally and loadings up to approximately 6 t were involved. Spatial harmonics were eliminated or selected by appropriate placing of a small scintillation detector. Experimental results showing the dependence of decay constant on buckling are presented and compared with theoretical values. (author) [French] On a utilise conjointement un assemblage sans reflecteur uranium naturel-eau ordinaire et une source puisee en vue de mesurer le temps de decroissance pour differents laplaciens. - Plusieurs paires de plaques de reseau usinees avec precision ont permis d'adopter quatre differents pas de reseau allant de 3,94cm a 5,08 cm; dans chaque cas, l'uranium etait sous forme de barres de 109,8 cm de long et de 3,0 cm de diametre. Le combustible etait monte horizontalement et le chargement a atteint parfois jusqu'a pres de 6 t. Grace a un petit detecteur a scintillations convenablement place, on a pu eliminer les harmoniques spatiaux ou les selectionner. Les auteurs presentent des resultats d'experiences qui montrent les variations de la constante de desintegration en fonction du laplacien, et les comparent avec les valeurs theoriques. (author) [Spanish] Los autores utilizaron un conjunto de uranio natural y agua ligera, sin reflector, juntamente con una fuente neutronica pulsante, para efectuar determinaciones del tiempo de desintegracion en correspondencia con diferentes valores del laplaciano. En este conjunto se pueden establecer cuatro diferentes espaciamientos del reticulado, desde 3,94 cm hasta 5,08 cm. utilizando diferentes pares de placas de

  2. The Co{sup 60} Irradiation Facility and the Gamma Field at Riso; Appareil d'irradiation au cobalt-60 et champ sous irradiation gamma, a Riso; Ustanovka dlya obluchenij, rabotayushchaya na So60, i pole gamma-luchej v rizo; Instalacion de irradiacion con cobalto-60 y campo de irradiacion gamma en el centro de Riso

    Brynjolfsson, A; Holm, N W [Danish Atomic Energy Commission, Establishment Riso (Denmark)

    1960-07-15

    The paper describes both the Co{sup 60} irradiation facility and the gamma field at the Agricultural Department of the Research Establishment, Riso. The Co{sup 60} irradiation facility contains 1,800 curies of Co{sup 60.} Details of the construction are given together with the safety precautions which have been included in the design. Dosimetry has been carried out by four different methods: 1. Ionisation chambers, 2. Calorimetry, 3. Fricke dosimeter, 4. Photographic films. A general outline is given of the gamma field, including details of source position. The dose rate is approximately 100 r./hr. at a distance of 1 m. An area of radius 15 m is used for the growing of plants under irradiation. A brief indication is given of the class of products which have been irradiated in the two facilities. (author) [French] Le memoire decrit l'appareil d'irradiation au cobalt-60 et le champ sous irradiation gamma du Departement de l'agriculture de l'Organisme de recherche de Riso. L'appareil d'irradiation au cobalt-60 contient une source de 1 800 curies. Des details sont donnes sur la construction ainsi que sur les dispositifs de protection compris dans le plan. Quatre methodes differentes ont ete utilisees pour la dosimetrie: 1. Chambres d'ionisation 2. Calorimetrie 3. Dosimetrie de Fricke 4. Pellicules photographique s On donne un apercu general du champ gamma, ainsi que des details sur la position de la source. L'intensite de dose est de 100 R/h environ a une distance de 1 m. Une zone d'un rayon de 15 m est utilisee pour la croissance des plantes soumises a l'irradiation. Des indications sommaires sont donnees sur la categorie des produits qui ont ete soumis a l'irradiation dans les deux installations. (author) [Spanish] Los autores describen la instalacion de irradiacion con cobalto-60 y el campo de irradiacion gamma del Departamento de Agronomia del Instituto de Investigaciones de Riso. El dispositivo de irradiacion consiste en una fuente de cobalto-60 de 1 800 curies

  3. Etude par Spectrométrie de masse de la décomposition thermique sous vide de kérogènes appartenant à deux lignées évolutives distinctes Mass Spectrometry Investigation of the Vaccum Thermal Decomposition of Kerogens from Two Distinct Evolutive Lines

    Souron C.

    2006-11-01

    Full Text Available Le but de cette étude est la connaissance qualitative et quantitative des composés dégagés lors de la décomposition thermique sous vide de quelques échantillons de kérogènes appartenant à deux lignées différentes. La principale technique utilisée est la spectrométrie de masse, appuyée sur des études préliminaires par thermogravi métrie et analyse élémentaire. Une adaptation particulière de l'appareillage et une mise au point de la méthode d'étalonnage permettent de doser les quatre composés minéraux les plus abondants et de donner une représentation des composés organiques. Cette étude montre que les composés formés au cours du chauffage comprennent, pour tous les kérogènes étudiés, des composés oxygénés et soufrés (CO, H2O, SH2, SOJ libérés principalement dans l'intervalle de température 200-400° C, et des composés hydrocarbonés, plus abondants, dans l'intervalle 300-500° C. On commente dans cet article l'origine supposée de ces composés; la formation de S02 au cours de la pyrolyse est particulièrement mal connue. On remarque que le rapport H2O/C02 peut être un critère de distinction des deux lignées de kérogènes étudiés. La distinction observée sur les produits hydrocarbonés nécessitera des recherches complémentaires pour être utilisée avec plus de sûreté. The aim of this investigation is to obtain a qualitative and quantitative understanding of the compounds given off during the vacuum thermal decomposition of several kerogen samples from two different lines. The main technique used is mass spectrometry, based on prior investigations by thermogravimetry and element onalysis. The equipment was specially adapted and a calibration method was developed for titrating the four most abundant minerai compounds and for representing the organic compounds. This investigation shows that the compounds formed during heating include, for oil the kerogens examined, oxygen-and sulfur

  4. Carcinogenesis by Fast Neutrons Relative to X-Rays in Mice; Carcinogenese chez les Souris sous l'Effet des Neutrons Rapides et des Rayons X; Sravnitel'naya chastota vozniknoveniya rakovykh opukholej u myshej pri obluchenii bystrymi nejtronami i rentgenovskimi luchami; Accion Carcinogenica Comparada de los Neutrones Rapidos y de los Rayos X en el Raton

    Cole, L. J.; Nowell, P. C. [Division of Biological and Medical Sciences, U.S. Naval Radiological Defense Laboratory, San Francisco, CA (United States); Department of Pathology, School of Medicine, University of Pennsylvania, Philadelphia, PA (United States)

    1964-05-15

    ). Parmi les souris du Groupe I, sacrifiees 12 a 16 mois apres l'exposition, 75% presentaient des hepatomes; ce taux atteignait 92% chez les souris du Groupe II. Par contre, des tumeurs du foie se sont produites chez 14% des souris exposees seulement aux neutrons (Groupe V) et chez 2,4% des souris exposees a une dose unique (500 rad) de rayons X de 250 kVcrete. On a observe des neoplasmes du rein chez pres de 100% des souris du Groupe IV, alors que ces lesions ont ete peu frequentes chez les souris temoins. Les auteurs etudient Inverted-Exclamation-Mark ' induction de ces neoplasmes sous l'effet de l'exposition aux neutrons et leur developpement sous l'action des agent employes pour stimuler la proliferation. En ce qui concerne l'induction de neoplasmes du rein chez les souris, les donnees indiquent un coefficient de puissance d'environ 2 pour les neutrons de fission par rapport aux rayons X de 250 kV-crete. Pour ce qui est de l'apparition de lymphomes dans cette lignee, leur frequence a ete moins importante chez les souris exposees aux neutrons (11%) que chez les sujets exposes aux rayons X (29%). (author) [Spanish] Los autores sometieron ratones jovenes adultos de la variedad LAF a una exposicion subletal unica a neutrones de fision, tratandolos de la siguiente forma: Grupo I: 195 a 199 rad, seguida de una sola inyeccion subcutanea de CCl{sub 4}, un mes despues de la exposicion; Grupo II: inyeccion de CCl{sub 4} aplicada un dia antes de la irradiacion neutronica (280 y 329 rad); Grupo III: inyeccion de CCl{sub 4} sin irradiacion; Gmpo IV: nefrectomfa unilateral un dia antes de la irradiacion (320 y 328 rad); Grupo V: irradiacion neutronica exclusivamente (200 y 320 rad). Al sacrificar los sujetos entre 12 y 16 meses a contar de la irradiacion, se encontraron hepatomas en el 75% de los ratones del Grupo I y en el 92% de los del Grupo II. En cambio, los tumores hepaticos aparecieron en el 14% de los ratones que solo fueron irradiados (Grupo V) y en el 2,4% de los expuestos

  5. The Measurement of Reactivity In Multiregion Subcritical Systems by the Pulsed Neutron Technique; Mesure de la Reactivite dans les Systemes Sous-Critiques a Plusieurs Regions par la Methode des Neutrons Pulses; Izmerenie reaktivnosti v mnogozonnykh podkriticheskikh sistemakh metodom impul'snykh nejtronov; Mediciones de la Reactividad en Sistemas Subcriticos de Varias Regiones Mediante la Tecnica de los Neutrones Pulsados

    Sherwin, J.; Leng, J. H. [United Kingdom Atomic Energy Authority, Windscale Works, Cumberland (United Kingdom)

    1965-10-15

    The prompt decay of a thermalized burst of neutrons in a multiregion subcritical system is examined using a two-group diffusion theory. It is shown that a relationship can be established between the prompt decay constant of the fundamental mode and the effective multiplication factor of the system in terms of two parameters, defined, for the purposes of this paper, as the reactor response coefficient and the prompt decay correction and which depend to a large extent on the spatial flux patterns within the system. For the uniform bare system, the response coefficient can be identified with the mean neutron lifetime in the system; for a multiregion system it represents a compound of the lifetimes in each region weighted by perturbation type integrals. The second parameter, the decay correction, can have no physical meaning in that it arises from an attempt to relate the two scales of reactivity involved; that is the scale using the prompt decay constant and the scale derived using the effective multiplication factor. The properties of these parameters are examined here with reference to an enriched uranium graphitemoderated reactor consisting of uniform core and reflector and it is shown that the two parameters are not uniquely defined by the reactivity of the system but depend on the method chosen to make the system subcritical. Two sets of measurements are treated by the theory. In one, the Windscale Advanced Gas-Cooled Reactor was shut down by a uniform poison. In the other the reactivity of a core in the zero-energy reactor HERO was varied by altering the loaded radius. The neutron pulse measurements are all shown to be in good agreement with more conventional methods of reactivity determination. Some discussion of the experimental techniques and the difficulties encountered in the graphite-moderated systems is presented. (author) [French] Les auteurs etudient la decroissance des neutrons instantanes d'une bouffee thermalisee de neutrons dans un systeme sous

  6. Research with a Natural-Uranium Light-Water Subcritical Assembly; Recherches au Moyen d'un Ensemble Sous-Critique a Uranium Naturel et a Eau Ordinaire; Issledovaniya na podkriticheskoj sborke,rabotayushchej na prirodnom urane i obychnoj vode; Investigaciones con un Conjunto Subcritico de Uranio Natural y Agua Ligera

    Koskinen, H. [Institute of Technical Physics, Otaniemi (Finland)

    1964-02-15

    systematic study of non-uniform lattices. In the future, enriched elements will be included in the assembly. Then systematic study of mixed lattices becomes possible, and also research with other non-uniformities will be easier because of the higher flux. Some discussion of this future programme is included in this paper. (author) [French] L'auteur relate les recherches effectuees avec un ensemble uranium naturel-eau ordinaire et enumere certains des sujets qui feront l'objet d'un prochain programme. La plus grande partie de la documentation est nouvelle. Certaines donnees ont encore un caractere provisoire, car les experiences et l'analyse des resultats se poursuivent. . Les travaux sont axes sur deux objectifs principaux: 1. Etude experimentale de la validite des methodes de calcul que l'on se propose d'utiliser, notamment en cas de geometries speciales (repartitions non uniformes du combustible, configurations de s'ous- ensembles, limites de forme particuliere, etc.). Les etudes theoriques conduisent souvent ici a certaines difficultes de convergence. Il faut donc les comparer avec les repartitions du flux mesurees. 2. Etude des proprietes particulieres des reseaux uranium naturel-eau ordinaire et notamment de la validite des modeles de ralentissement a plusieurs groupes pour des structures de coeur uniformes et non uniformes. On pense qu'un ensemble comportant une seule source de fission spontanee convient particulierement pour les recherches de ce genre, bien que la statistique ne porte que sur un petit nombre d'observations. Cela est du a deux faits: 1. On peut considerer que le spectre de la source primaire est identique a celui de la fission induite, si bien qu'il n'y a pas d'oscillations transitoires d'energie, comme dans le cas d'une source ponctuelle de neutrons rapides. 2. L'intensite de la source primaire en chaque point de l'espace est proportionnelle a la section efficace de fission du combustible lorsqu'on considere egalement cette derniere comme une fonction

  7. Construction and Operation of a Commercial Gamma-Ray Package-Sterilizing Plant; Construction et fonctionnement d'une installation industrielle pour la sterilisation d'articles sous emballage par les rayons gamma; Razrabotka i ehkspluatatsiya sbornoj ustanovki gamma-izlucheniya promyshlennogo tipa dlya sterilizatsii meditsinskikh materialov; Construccion y funcionamiento de una instalacion industrial para la esterilizacion gamma de articulos medicos empaquetados

    Crawford, C. G. [Johnson' s Ethical Plastics Ltd., Slough (United Kingdom)

    1963-11-15

    The purpose of the paper is to describe the Co{sup 60} sterilizing plant now being operated commercially by Johnson's Ethical Plastics Limited, at Slough, England. This is a continuous process plant with a source of 72000 c and completely automatic operation. Based on experience gained by U.K.A.E.A. in their Package Irradiation Plant at Wantage, the present plant was designed specifically for sterilization of disposable plastic syringes and other medical products of similar bulk density. The plant has been in operation since November 1962. A description is given of the main features of its construction, including personnel safety devices, and method of loading the source rods. Operating experience is described including dosimetry, integration of the plant into a commercial undertaking as a production process, and bacteriological results. A short discussion on the economics of sterilizing by gamma radiation is given and an assessment of possible future applications of a plant of this type. (author) [French] Le memoire est consacre a la description de l'installation de sterilisation au cobalt-60, actuellement exploitee industriellement par la Johnson Ethical Plastics Ltd., a Slough (Angleterre). Cette installation, equipee d'une source de 72 000 c, fonctionne en continu et toutes les operations y sont automatiques. Fondee sur l'experience acquise par l'Autorite de l'energie atomique du Royaume-Uni dans son installation d'irradiation d'articles sous emballage, de Wantage, l'installation decrite est specialement destinee a la sterilisation de seringues en matieres plastiques et d'autres instruments medicaux non recuperables de densite apparente analogue. L'installation est en service depuis novembre 1962. Le memoire decrit ses principales caracteristiques, y compris les appareils de protection du personnel et les dispositifs de chargement des barreaux utilises comme sources. L'auteur fournit des donnees d'ordre pratique, notamment sur la dosimetrie, l'integration de l

  8. The Main Technological Characteristics of Apparatus for Industrial Radiochemical Processes, in Particular Ethylene Polymerization; Caracteristique techniques fondamentals des appareils pour l'application industrielle de reactions chimiques sous rayonnement (notamment la polymerisation de l'ethylene ); Osnovnye tekhnologicheskie kharakteristiki apparatov dlya provedeniya radiatsionno-khimi-cheskikh protsessov (v chastnosti, dlya polimerizatsii ehtilena) v promyshlennom masshtabe; Principales caracteristicas tecnologicas de los aparatos para la aplicacion industrial de reacciones radioquimicas

    Syrkus, N P; Breger, A K; Weinstein, B I [Karpov Physicochemical Institute, Moscow, USSR (Russian Federation)

    1960-07-15

    The paper gives a general review of some of the main technological features of apparatus, for instance spherical apparatus, for industrial radiochemical processes. A method is proposed for estimating the effectiveness of apparatus of any given construction by comparing it with the output of an infinitely large apparatus having the same radiation source. An account is given of the technological features of an apparatus for radio-polymerizing ethylene at 200 atmospheres and 25{sup o}C{sup 1} with a rodshaped gamma-radiation source (Co{sup 60}) of variable activity. This apparatus can be designed to suit the mean dose rate which the power efficiency of the apparatus allows. It is shown that the yield, Q, of the apparatus is, other things being equal, a constant ration of the power, W{sub 0}, of the gamma-radiation of the apparatus. In the apparatus reviewed, Q {approx} W{sub 0}{sup 0,5}. (author) [French] Le memoire contient un expose general des caracteristiques techniques essentielles des appareils, par exemple d'un appareil du type spherique, pour l'application industrielle de reactions chimiques sous rayonnement. Le memoire propose une methode pour evaluer l'efficacite d'appareils de tous types en comparant la productivite de chaque modele avec celle d'un appareil infiniment grand, alimente par une source de rayonnement identique. Le memoire indique le calcul des caracteristiques techniques de l'appareil destine a la polymerisation sous rayonnement de l'ethylene (pression : 200 atmospheres, temperature: 25{sup o}C{sup 2} avec une source allongee de rayonnement gamma Co{sup 60} pour diverses activites. Un appareil de ce type peut etre calcule selon les valeurs moyennes de l'intensite des doses, determinees selon la valeur du coefficient d'efficacite totale energetique de l'appareil. On constate que la productivite (Q) de l'appareil, toutes choses egales d'ailleurs, est puissance de l'intensite (W{sub 0}) du rayonnement gamma de l'appareil. Pour l'appareil considere

  9. Physical Properties of P.V.C. Attenuated Network Copolymers Produced by Ionizing Radiation; Proprietes physiques des copolymeres obtenus sous l'action de rayonnements ionisants et dont le reseau est attenue par l'effet du chlorure de polyvinyle; Fizicheskie svojstva polivinilkhloridnykh obednennykh tsepej sopolimerov, poluchennykh v rezul'tate vozdejstviya ioniziruyushchej radiatsii; Propiedades fisicas de los copolimeros de redes atenuadas por cloruro de polivinilo obtenidos por irradiacion

    Pinner, S H [Tube Investments Research Laboratories, Hinxton Hall, Cambridge (United Kingdom)

    1960-07-15

    The cross-linking of polyvinyl chloride with ionizing radiation poses special problems. Due to rather unfavourable cross-linking and dislinking parameters for this polymer, the radiation doses necessary for high cross-link densities are uneconomicall y large and discolouration and dehydrohalogenatio n are simultaneously produced. These difficulties have been overcome by the incorporation into the P. V. C., prior to irradiation, of diallyl and triallyl esters. Heavily cross-linked products are thereby obtained with relatively low doses of ionizing radiation. Examination of the physical properties of the products suggests that these are not simply graft copolymers, which term normally implies the presence of long branch chains, but are polymer attenuated allyl networks. In these materials, the desirable properties of the parent polymer and of the allyl network are combined. The tensile strength, modulus and elongation of the attenuated network copolymers are presented and discussed as a function of temperature and of the concentration and functionality of the allyl ester. Reference is also made to the swelling and chemical resistance of the products. (author) [French] La reticulation du chlorure de polyvinyle sous l'action des rayonnements ionisants pose des problemes particuliers. Les parametres de reticulation et de degradation etant plutot defavorables pour ce polymere, les doses d'irradiation necessaires a l'obtention de fortes densites de pontage sont trop elevees pour donner des resultats economiquement interessants; elles provoquent simultanement la decoloration et la deshalogenhydratation. Il a ete possible de surmonter ces difficultes par introduction d'esters diallyliques et triallyliques dans le chlorure de polyvinyle, avant irradiation. Ce procede permet d'obtenir au moyen de doses d'irradiation relativement faibles des produits fortement reticules. L'etude des proprietes physiques de ces produits montre qu'il s'agit non pas de simples copolymeres greffes

  10. « Le nez dans le micro ». Répercussions du travail sous commande vocale dans les entrepôts de la grande distribution alimentaire “Up front and close”. The impact of voice guidance systems in large food distribution warehouses “Estar pegado al micrófono”. Repercusiones del trabajo de activación por voz en los almacenes de la distribución alimentaria masiva

    David Gaborieau

    2012-12-01

    Full Text Available Dans les entrepôts de la grande distribution alimentaire, l’introduction d’un nouvel outil de travail, le guidage par commande vocale, a considérablement modifié le travail des préparateurs de commande. Auparavant caractérisée par l’absence d’enchaînement et la possibilité de prendre de l’avance, l’activité de préparation a évolué vers une temporalité restrictive comparable à celle d’un ouvrier sur chaîne. Sous guidage vocal, « le nez dans le micro », le savoir-faire des préparateurs est réduit à un engagement physique. L’usage du corps constitue alors une ressource en tant mode d’appropriation du sens au travail, mais également un rempart lorsque des pathologies font apparaître les limites de l’intensification.Order picker operations in large food distribution warehouses have been considerably changed by a introduction of a new tool – voice guidance systems. Where the work used to be characterized by a lack of fixed sequencing and the impossibility for operatives of getting ahead of schedule, preparation activities have evolved towards more restrictive temporalities comparable to production line workers’ experience. With “up front and close” vocal guidance, order pickers’ skill is limited to their physical engagement, now considered a resource (i.e. a mode for appropriating the meaning of work but also a bulwark against the pathologies that arise as the general intensification drive reaches its limits.En los almacenes de la distribución alimentaria a gran escala, la introducción de una nueva herramienta de trabajo, el guiado activado por voz, ha transformado considerablemente el trabajo de los preparadores de pedidos. La actividad de preparación, antes caracterizada por la ausencia de secuenciación y por la posibilidad que el trabajador tenía de ganar tiempo, ha evolucionado hacia una temporalidad restrictiva comparable a la de un obrero en una cadena. Con el guiado activado por voz, al

  11. Underground disposal of tanks containing liquid and inflammable hydrocarbons; Mise sous talus ou sous terre des reservoirs contenant des hydrocarbures liquides inflammables

    Kukuczka, P.; Giovannini, B.; Caumont, M.; Varin, F

    2001-09-15

    The protection from thermal and mechanical stresses, of hazardous products tanks, by earth covering, is often used since many years in France and in many countries of Europe. In the case of hydrocarbons tanks, only small capacity tanks are covering. The aim of this report is to evaluate the feasibility of this technique for big capacity tanks as refinery tanks. It details the different typologies of tanks containing inflammable liquids and the associated systems, examines if the covering technique presents some special difficulties and precises the specifications needed for the new tanks being covering. (A.L.B.)

  12. Studies in Petroleum Composition the Distribution of Nitrogen Species, Metals and Coke Precursors During High Vacuum Distillation of Petroleum Étude de composition du pétrole Répartition des espèces azotées, des métaux et des précurseurs du coke pendant la distillation sous vide poussé du pétrole

    Long R. B.

    2006-11-01

    °F d'un milieu hydrocarbure dispersant. Un tel phénomène donnerait des rendements plus élevés en asphaltènes dans A-1289 °F que dans A-950 °F. Si l'on fait un sous-fractionnement des fractions 940-1289 °F et + 1289 °F par la technique d'adsorption sur céramique, on observe également des phénomènes intéressants. La fraction 950-1289 °F comporte principalement des hydrocarbures saturés (60% et aromatiques (26,5% mais également des produits polaires (13,2 % ; 13,5% avec un adsorbant; en revanche, la fraction + 1289 °F contient très peu d'hydrocarbures saturés (3,7 % mais les aromatiques (42,3 % et produits polaires (52,7 % ; 54 avec un adsorbant y sont prédominants. Les résultats montrent que poursuivre la distillation du résidu + 950 °F permet de récupérer essentiellement tous les produits saturés de la charge dans le produit supérieur au point de coupe de 1289 °F. Toutefois, des quantités appréciables de produits polaires contenant de l'oxygène et de l'azote sont également dans le produit supérieur, ce qui donne pour le distillat une valeur de 8,2 % en poids du résidu de carbone. Les métaux et les produits de tête du distillat sont principalement dans la fraction polaire avec les composés azotés. Toutefois, à ces poids moléculaires élevés, le distillat comporte également des produits de tête dans la fraction saturée et dans une plus forte proportion dans la fraction aromatique. La distillation est un processus de concentration des impuretés (carbures de tête, hétéroatomes, métaux. Lorsque le point de coupe s'élève, le contenu en impuretés du distillat augmente, mais il augmente moins que celui du résidu correspondant.

  13. Creep-fatigue propagation of semi-elliptical crack at 650 deg. C in 316L(N) stainless steel plates with or without welded joints; Propagation de fissures semi-elliptiques en fatigue-fluage a 650 deg. C dans des plaques d'acier 316L(N) avec ou sans joints soudes

    Curtit, F

    2000-07-01

    This study realised in LISN Laboratory of CEA Saclay, deals with the creep fatigue propagation of semi elliptical crack at the temperature of 650 deg C in 316L(N) stainless steel plates with or without welded joints. A vast majority of the studies on creep fatigue propagation models are based on specimen (CT) especially designed for crack propagation study. The PLAQFLU program performed in LISN laboratory deals with the application and adaptation of these models to complex crack shape, which are more representative of the cracks observed in industrial components. In this scope, we use propagation tests realised at the temperature of 650 deg C with wide plates containing semi elliptical defects. For some of them, the initial defect is machined in the middle of a welded joint, which constitute a privileged site for the crack initiation. The approach used in this study is based on global parameters of fracture mechanics. At first, tests on CT specimen are used in order to determine the propagation laws correlating the crack growth rate to the global parameters K or C{sup *}. These laws are then supposed to be intrinsic to our materials and are used to analysed the semi elliptical crack propagation. The analysis of the comportment of the crack during the hold time demonstrates the possibility to establish a correlation between the crack propagation both in the deepest and the surface point and the local value of C{sup *}. These correlations are coherent in the different points of the crack front for the different applied hold times, and they present a reasonably good agreement with the creep propagation law identified on CT specimen. The simulation of test performed on based metal specimen with a model of summation of both creep and pure fatigue crack growth gives acceptable results when the calculus of the simplified expression of C{sup *}{sub s} considers a continuous evolution of creep deformations rate during the all test. (author)

  14. Fictitious domain methods for elliptic problems with general boundary conditions with an application to the numerical simulation of two phase flows; Methodes de domaine fictif pour des problemes elliptiques avec conditions aux limites generales en vue de la simulation numerique d'ecoulements diphasiques

    Ramiere, I

    2006-09-15

    This work is dedicated to the introduction of two original fictitious domain methods for the resolution of elliptic problems (mainly convection-diffusion problems) with general and eventually mixed boundary conditions: Dirichlet, Robin or Neumann. The originality lies in the approximation of the immersed boundary by an approximate interface derived from the fictitious domain Cartesian mesh, which is generally not boundary-fitted to the physical domain. The same generic numerical scheme is used to impose the embedded boundary conditions. Hence, these methods require neither a surface mesh of the immersed boundary nor the local modification of the numerical scheme. We study two modelling of the immersed boundary. In the first one, called spread interface, the approximate immersed boundary is the union of the cells crossed by the physical immersed boundary. In the second one, called thin interface, the approximate immersed boundary lies on sides of mesh cells. Additional algebraic transmission conditions linking both flux and solution jumps through the thin approximate interface are introduced. The fictitious problem to solve as well as the treatment of the embedded boundary conditions are detailed for the two methods. A Q1 finite element scheme is implemented for the numerical validation of the spread interface approach while a new cell-centered finite volume scheme is derived for the thin interface approach with immersed jumps. Each method is then combined to multilevel local mesh refinement algorithms (with solution or flux residual) to increase the precision of the solution in the vicinity of the immersed interface. A convergence analysis of a Q1 finite element method with non-boundary fitted meshes is also presented. This study proves the convergence rates of the present methods. Among the various industrial applications, the simulation on a model of heat exchanger in french nuclear power plants enables us to appreciate the performances of the fictitious domain methods introduced here. (author)

  15. Industrial applications of radiation chemistry; Perspectives industrielles de la chimie sous rayonnement

    Puig, Jean Rene [Commissariat a l' energie atomique et aux energies alternatives - CEA, Service de chimie-physique, CEN de Saclay (France)

    1959-07-01

    The status of industrial applications of radiation chemistry as it stands 6 months after the second Geneva international conference is described. The main features of the interaction of ionizing radiations with matter are briefly stated and a review is made of the best studied and the more promising systems of radiation chemistry. The fields of organics, plastics, heterogeneous catalysis are emphasized. Economies of radiation production and utilization are discussed. Reprint of a paper published in Industries atomiques - no. 5-6, 1959.

  16. Détection binaire distribuée sous contraintes de communication

    Katz , Gil

    2017-01-01

    In recents years, interest has been growing in research of different autonomous systems. From the self-dring car to the Internet of Things (IoT), it is clear that the ability of automated systems to make autonomous decisions in a timely manner is crucial in the 21st century. These systems will often operate under stricts constains over their resources. In this thesis, an information-theoric approach is taken to this problem, in hope that a fundamental understanding of the limitations and pers...

  17. Garder la tête froide sous le réchauffement climatique.

    Hervé Regnauld

    2009-03-01

    Full Text Available La notion de risque est habituellement définie par les sciences sociales comme la rencontre d’un aléa et d’une vulnérabilité. Ainsi, si une tempête survient en pleine mer là où aucun bateau n’est présent, il n’y a aucun risque : il y a un aléa sans vulnérabilité ; tandis que si elle survient sur la côte et que la force des houles risque de briser une jetée il y a risque : l’aléa rencontre un aménagement vulnérable. Cette approche fait du risque un phénomène ...

  18. Ripa Vticensis. Le renseignement militaire en Afrique sous le Haut-Empire

    Yann Le Bohec

    2018-01-01

    Full Text Available The notion of ripa under the Principate has not attracted the interest of specialists in Africa. Yet a structure of this kind is present in this part of the empire; it is found in an inscription that mentions a ripa Vticensis. What is it about ? To give an answer, it should be seen that this word was used in a military context in these provinces, for Utica and Hippo, also elsewhere, for the Danube and the Euphrates.   Published online 15/01/2018

  19. Feasibility study for a deep thermal exchanger at Soultz-sous-Forets (Alsace, France)

    Elsass, P.; Aquilina, L.; Beauce, A.; Benderitter, Y.; Fabriol, H.; Genter, A.; Pauwels, H.

    1995-01-01

    This project is part of the European program on deep geothermics research. It consists in the interpretation of structural, geochemical and geophysical data collected on Soultz site, in the simulation and the experimental validation of rock-fluid interactions in the exchanger, and in the simulation of structural, thermal and hydraulic characteristics of the site. The principal event in this project for 1994 was the starting of the GPK2 drilling for a characterization of the hydraulic connections at a 3000 m depth with the existing GPK1 borehole. The interpretation of borehole images of structures and alterations in GPK1 has led to the construction of a structural model of the granitic massif characterized by large N-S and NW-SE accidents in which hydrothermal alteration has developed. The localisation of micro-earthquakes induced by the hydraulic injections in GPK1 shows a well-structured cloud due to the interference between the stress field and the faulted structures. The geochemical composition of fluids produced by GPK1 after stimulation shows a rapid replacement of the injected fresh water by salty fluids. These fluids are supposed to belong to hydrothermal convection loops installed in fractured zones and connected to the overlying Buntsandstein sandstone reservoir. (J.S.). 4 figs

  20. The N=16 subshell closure; La fermeture de sous-couche N=16

    Obertelli, A

    2005-09-01

    The sequence of magic numbers for stable nuclei is now well understood. However the magnitude of shell gap may evolve from stability to drip line. Several observables show that N = 16 neutron-rich isotones present a higher stability compared to their neighbors on the N-Z chart. The spectroscopy of the levels of Ne{sup 27}, involving sd and fp shells, has allowed us to study the evolution of the nuclear shells responsible for the structure changes in N 16 isotones. In this framework we have studied the neutron transfer reaction Ne{sup 26}(d,p)Ne{sup 27} by inverted kinematics at 9,7 MeV/u. A cryogenic D{sub 2} target (17 mg.cm{sup -2}) has been used. The use of the magnetic spectrometer Vamos and that of the Exogam photon detector in coincidence operating mode has allowed us to achieve the spectroscopy of Ne{sup 27}. The results show a reduction in the gap between sd and fp shells for N = 17 isotones as we go from stability toward the neutron drip line. We have also performed a theoretical study in mean-field theory and beyond it through configuration mixing so that we can see the evolution of the isospin of the N = 16 subshell's closure. We have used a HFB (Hartree-Fock-Bogoliubov) with the finite range D1S effective interaction. (A.C.)

  1. The colours of strong interaction; L`interaction forte sous toutes ses couleurs

    NONE

    1996-12-31

    The aim of this session is to draw a consistent framework about the different ways to consider strong interaction. A large part is dedicated to theoretical work and the latest experimental results obtained at the first electron collider HERA are discussed. (A.C.)

  2. Innovations en matière de recherche : examiner les problèmes sous ...

    Produire les connaissances et les utiliser pour améliorer les conditions de vie des populations dans l'ensemble des pays en développement a toujours été au coeur des activités du CRDI. Cette démarche a donné naissance à des champs de recherche novateurs :

  3. Metal extrusion using hydrostatic pressures; Le filage des metaux sous pression hydrostatique

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

    1965-07-01

    The main problems connected with the deformation of metals due to extrusion are described. A method is put forward for calculating the rational rate of percentage deformation in the case of bar extrusion using a cylindrical container; reference is made to previous work on extrusion using a hydrostatic pressure with or without back-pressure. An extrusion process is described using hydrostatic pressure, without back-pressure, and using the lubricant for transmitting the thrust. This process has been used for eight years by the C.E.A. for the extrusion of a very wide range of metals, from beryllium to uranium and including steels; it leads to excellent surface textures. A very fine crystallization can be obtained on extruded products when the rate of extrusion is very low. There appears to be nothing against the use of high extrusion rates using this method. (author) [French] On expose les problemes generaux lies a la deformation des metaux par filage. On propose un calcul de la vitesse rationnelle de deformation pour cent dans le cas du filage de barres a partir d'un conteneur cylindrique, et l'on cite les travaux anterieurs sur le filage par faction d'une pression hydrostatique sans ou avec une contre-pression. On decrit un procede de filage par l'action d'une pression hydrostatique, sans contre-pression, utilisant le lubrifiant pour transmettre la poussee. Ce procede employe depuis 8 ans au C.E.A. pour filer les metaux les plus divers, depuis le beryllium jusqu'a l'uranium en passant par les aciers, permet d'obtenir d'excellents etats de surface. Une cristallisation tres fine peut etre obtenue sur les produits files lorsque le filage est tres lent. Rien ne parait s'opposer a ce que des filages rapides soient effectues avec cette methode. (auteur)

  4. CBMA [Chartae Burgundiae Medii Aevi] – VI. Les chartes bourguignonnes sous Philologic

    Eliana Magnani et Marie-José Gasse-Grandjean

    2011-01-01

    Depuis l’été 2010, les chartes bourguignonnes réunies dans la base des CBMA peuvent être interrogées librement sur internet avec le logiciel Philologic [http://www.artehis-cbma.eu/]. Il s’agit, actuellement, du seul corpus diplomatique étendu permettant, entre autres, la recherche de cooccurrences, un affichage par mot-clé, par distribution chronologique et par fréquence, qui incitent aux nouvelles lectures des documents, à la comparaison des pratiques scripturaires et de leur diffusion ou à ...

  5. Interaction ligand – proteine : la sensation d’astringence sous les rayons VUV de DESIRS

    Canon, Francis

    2013-01-01

    L’astringence est la sensation d’assèchement et de rugosité à l’intérieur de la bouche qui accompagne la consommation de produits d’origine végétale, tels que le vin ou le thé, ou certains fruits peu mûrs. Les tanins, métabolites secondaires des végétaux, sont à l’origine de cette sensation, qui reste encore mal caractérisée. Une nouvelle approche utilisant la spectrométrie de masse couplée au rayonnement VUV, développée sur les lignes DESIRS et DISCO, a permis de mieux comprendre les mécanis...

  6. The colours of strong interaction; L`interaction forte sous toutes ses couleurs

    NONE

    1995-12-31

    The aim of this session is to draw a consistent framework about the different ways to consider strong interaction. A large part is dedicated to theoretical work and the latest experimental results obtained at the first electron collider HERA are discussed. (A.C.)

  7. Effets d'amendements organiques et phosphatés sous zaï sur les ...

    sub-sahélienne pour pallier l'aridité climatique dans un contexte de changements globaux. ... étude est de proposer une pratique culturale adaptée à la restauration des ... Africa, to address the climate aridity in a context of global changes.

  8. Vacuum fusion of uranium; Fusion de l'uranium sous vide

    Stohr, J. A.

    1957-06-04

    After having outlined that vacuum fusion and moulding of uranium and of its alloys have some technical and economic benefits (vacuum operations avoid uranium oxidation and result in some purification; precision moulding avoids machining, chip production and chemical reprocessing of these chips; direct production of the desired shape is possible by precision moulding), this report presents the uranium fusion unit (its low pressure enclosure and pumping device, the crucible-mould assembly, and the MF supply device). The author describes the different steps of cast production, and briefly comments the obtained results.

  9. Insécurité alimentaire et sous-alimentation au Guatemala | CRDI ...

    Ce projet examinera et influera sur les politiques et les pratiques en matière de sécurité alimentaire et de nutrition pour l'agriculture à petite échelle. Un premier volet comportera la réalisation de huit études de cas ayant pour but d'analyser les situations où la sécurité alimentaire et les indicateurs de nutrition se sont ...

  10. MECANISME DE DEGRADATION DE FILMS DE POLYPROPYLENE IMPREGNE SOUS CHAMP ELECTRIQUE EN PRESENCE D'OXYGENE

    Said , Sylvère

    1994-01-01

    The concern of this body of work is the mechanism of dégradation of impregnated polypropylène film capacitors in an oxygen blanket. Tins study is carried out on plane électrode capacitor models with expérimental parameters (AC electrical field in the range 66 V/um-200 V/pm, oxygen blanket, température 80°C) which hâve enabled us to obtain results in good agreement with industrial capacitor behaviour.Capacitor ageing is mainly assessed by its mean life-time and the change in the physio-chemica...

  11. Electrical installations of the Channel tunnel; Installations electriques du Tunnel sous la Manche

    Kersabiec, G. de [Eurotunnel, Folkestone (United Kingdom)

    2002-08-01

    Like an underground factory, the railway and auxiliary equipments of the Channel tunnel between France and UK, need a reliable and redundant power supply with a high quality maintenance. This article presents: the design criteria of the power distribution systems, the installation itself and the organisation of its exploitation: 1 - transportation system of the Channel tunnel (loads to supply, exploitation imperatives, fundamental criteria); 2 - external power sources (connection to the UK and French grids, values used by the national grids); 3 - exploitation criteria, tunnel design; 4 - description (main UK and French power stations, 25 kV traction network, 21 kV distribution network, tunnels, lighting in railway tunnels, supply of terminals, earthing network); 5 - exploitation; 6 - maintenance and quality. (J.S.)

  12. Esclaves, «loisirs» et éducation sous l'Empire

    A. D. RIZAKIS

    2009-03-01

    Full Text Available RESUMEN: La relación entre dominus y servus no comienza a suavizarse hasta el último período de la época helenística. Este cambio se debe tanto a la influencia del estoicismo en las elites ciudadanas como a las transformaciones sufridas en el contexto político-social de ese período. Los esclavos empiezan a disfrutar de sus días libres y de esta manera pueden participar, casi regularmente, en festivales y banquetes, así como en el reparto de víveres y dinero. En cuanto a la educación, se producen menos cambios. Sólo algunas personas de condición servil disfrutan de una educación, gracias, generalmente, a la buena voluntad o el interés de su señor. En este sentido, Roma aparece más «generosa», impulsa la creación de escuelas para esclavos. En el mundo griego, por el contrario, los nacidos no libres solían quedar excluidos de los gimnasios; así el acceso sólo se les permitía para la unción y nunca para celebrar actividades deportivas o competiciones; las escasas excepciones confirman la regla. ABSTRACT: Dominus and servus relationship began to soften only in the last part of the Hellenistic age; this change was caused both by the influence of Stoicism on the civic elites and by the transformations in the political and social context which took place in this period. Slaves started to enjoy «jours de congé» and so were able to take part, almost regularly, in festivals and banquets, as well as in money and food distributions. As for education, there were fewer changes. Very few slaves were able to get an education, and this was generally due to their master’s willingness or interests. In regard to this, Rome appears to be more «generous», providing for the creation of slave schools. In the Greek world, on the contrary, non-freeborn individuals were usually debarred from the gymnasium, and when the latter opened its doors to slaves it was only for unction but never for athletic activities or contests; the rare exceptions to this rule confirm it.

  13. Planification multiagent sous incertitude orientée interactions : modèle et algorithmes

    Canu , Arnaud

    2011-01-01

    This thesis deals with partially observable multiagent decision-making problems. First of all, a state ofthe art describes the existing approaches (DEC-POMDP and its sub-models) : because of the exponentialcomplexity, they can not deal with real-world problems. Then, we introduce a new model, to avoid thiscombinatorial complexity. Our model is made of two parts : the rst one describes an individual problem(how the agent evolves, while ignoring the other agents) and the second one describes an...

  14. Cartographie et contrôle au Maroc sous le Protectorat espagnol (1912-1956

    José Luis Villanova

    2010-06-01

    Full Text Available La principale fonction des interventores (contrôleurs du Protectorat espagnol au Maroc entre 1912 et 1956 a consisté à surveiller l’action des autorités tribales marocaines pour asseoir la présence coloniale. Cependant, le Haut-Commissariat d’Espagne au Maroc leur a souvent demandé de préparer des rapports d’ordre économique, social ou à finalité militaire sur les tribus, généralement mal connues de l’autorité coloniale. Ces documents contiennent des cartes de qualité variée qui ont pu constituer un instrument précieux de contrôle et, dans certains cas, un outil de propagande au service de l’action coloniale espagnole.

  15. La justice guatémaltèque sous haute observation | CRDI - Centre de ...

    3 déc. 2004 ... C'est là une des affaires retenues par les chercheurs de l'Instituto de Estudios Comparados en Ciencias Penales de Guatemala (ICCPG ou Institut d'études comparatives en droit pénal du Guatemala) pour faire valoir la nécessité pour la société civile de suivre l'évolution de la justice. Avec l'appui financier ...

  16. LE BINOME EURO-DOLLAR SOUS LE SIGNE DE L’INCERTITUDE

    Ana Bal

    2009-03-01

    Full Text Available Will the Dollar remain the dominant international currency (mainly as a reserve currency? To answer this question, the paper presents in the first part the opinions of the most prominent experts concerning the determinant factors of an international currency status, in the two sphere of utilization: public and private. The most important are: the magnitude of the economies of emission, the externalities of network, the liquidity of their financial market, the confidence in their stability. Then there follows the evaluations concerning the two international currencies, Dollar and Euro, from these perspectives. Finally, the paper evaluates their role as measure of value, instrument of reserve and instrument of payment in the international economic relations. In the second part, the paper evaluates the recent tendencies of the exchange rate Euro/Dollar (2006-2008 from the point of view of fundamentals. After a period of depreciation, from the middle of the year 2008 until now, the dollar marked an unexpected appreciation towards the euro. But, the global financial and economic crisis increases the incertitude concerning the evolution of the exchange rate euro/dollar. Undoubtedly the two currencies will remain the prominent international currencies and the dollar the main reserve currency. Finally the paper presents Mundell’s proposal of stabilization of the binomial euro/dollar.

  17. Etude hartree-fock de la tautomerisation du 1azirene sous pression ...

    The lazirene molecule is a heterocyclic compound containing two carbon atoms, one nitrogen atom and three hydrogen atoms which one is on the nitrogen atom. The hydrogen pressure being represented by one molecule of dihydrogen, the reaction of the dihydrogen with the azirene in the presence of the palladium ...

  18. La réactivité des matériaux argileux sous gradient thermique

    Kohler , Eric

    2005-01-01

    Directrice de thèse : Catherine Beaucaire CEA Saclay Président du jury: Daniel Tessier INRA Versailles Rapporteurs : Martine Buatier Université de Franche-Comté, Besançon Sabine Petit Université de Poitiers Examinateurs : Justo Cabrera IRSN Fontenay aux Roses Michel Jullien CEA Cadarache Sid Labdi Université d'Evry Val d'Essonne Joël Raynal CEA Cadarache; The argillaceous materials properties could be favourable to the radioelements confinement in high activity and thermogenic nuclear waste d...

  19. Contribution à la coordination de flottille de véhicules sous-marins autonomes

    Spiewak , Jean-Mathias

    2007-01-01

    Our researches are related to coordination of torpedo-shaped autonomous underwater vehicles flotilla. The cooperation of such vehicles can generate a gain of time, energy, data and exploring area. Indeed, we study the modelling and the control, based on classic sliding mode, of a torpedo-shaped autonomous underwater vehicle. We also present a new high order sliding mode control law in order to limit chattering phenomenon acting on actuators. Finally, we propose a new control strategy to coord...

  20. Etat de l'art des véhicules sous-marins autonomes, verrous technologiques

    Michel, J; Duranton, R

    1990-01-01

    Autonomous Underwater Vehicles, also called "free-swimming vehicles" are self propelled bodies, equipped with their own energy package and with no solid communication link with the surface. At the beginning of the 90s, a renewed interest from the Underwater Intervention Community for autonomous vehicles and quite a number of new projects were announced or started. The present paper aims at presenting an updated State of the Art on the development of autonomous vehicles. It addresses the follo...

  1. Orobanche rameuse (Orobanche ramosa L. du colza : un risque émergent sous surveillance

    Gibot-Leclerc Stéphanie

    2006-03-01

    Full Text Available Broomrapes are parasitic plants without chlorophyll, nutritionally depending from their host plant. Orobanche ramosa L. is a parasite of numerous plants including winter oilseed rape. Its presence has been reported for a long time in the South of France. Nevertheless, its presence became a major problem in the Central West region Poitou-Charentes since the middle of the nineties. The phenomenon is under observation, and research work has been undertaken to evaluate its extension risks and to propose efficient solutions. The main extension factors are its ability to produce seeds, its wide ability to germinate in different environmental conditions, its large number of potential host plants, including common weeds present in cropped fields. Short term recommendations intend to favour the host in the nutritional competition and to limit the soil seed bank. For a longer term, several possibilities could be carried out : optimization of false hosts/trap-crops introduction in the rotation which could decrease the soil seed bank ; and breeding for herbicide resistant plants through mutagenesis or genetic transformation.

  2. Le cinquantenaire du CERN sous les feux de la rampe: vers le boson de Higgs

    2004-01-01

    CERN is celebrating today its 50th anniversary. Greatest physic Center in the world, he is setting up actually a new major instrument: the LHC. It should allow the discovery of the Higgs boson, angular stone of the theory of "standard model"

  3. Doped spin ladders under magnetic field; Echelles de spins dopees sous champ magnetique

    Roux, G

    2007-07-15

    This thesis deals with the physics of doped two-leg ladders which are a quasi one-dimensional and unconventional superconductor. We particularly focus on the properties under magnetic field. Models for strongly correlated electrons on ladders are studied using exact diagonalization and density-matrix renormalization group (DMRG). Results are also enlightened by using the bosonization technique. Taking into account a ring exchange it highlights the relation between the pairing of holes and the spin gap. Its influence on the dynamics of the magnetic fluctuations is also tackled. Afterwards, these excitations are probed by the magnetic field by coupling it to the spin degree of freedom of the electrons through Zeeman effect. We show the existence of doping-dependent magnetization plateaus and also the presence of an inhomogeneous superconducting phase (FFLO phase) associated with an exceeding of the Pauli limit. When a flux passes through the ladder, the magnetic field couples to the charge degree of freedom of the electrons via orbital effect. The diamagnetic response of the doped ladder probes the commensurate phases of the t-J model at low J/t. Algebraic transverse current fluctuations are also found once the field is turned on. Lastly, we report numerical evidences of a molecular superfluid phase in the 3/2-spin attractive Hubbard model: at a density low enough, bound states of four fermions, called quartets, acquire dominant superfluid fluctuations. The observed competition between the superfluid and density fluctuations is connected to the physics of doped ladders. (author)

  4. Comportement en flexion des bétons fibrés sous chargement cyclique

    Boulekbache Bensaid

    2014-04-01

    Full Text Available Ce papier présente les résultats d’une étude expérimentale sur le comportement en flexion des bétons de fibres métalliques. On étudie l’effet de la rhéologie du béton sur l’orientation des fibres et l’influence de l’orientation sur les propriétés mécaniques. La rigidité de l’ancrage des fibres étudiée par les essais cycliques est liée aux caractéristiques rhéologiques et mécaniques de la matrice. Les résultats montrent que la fluidité des bétons est un paramètre essentiel de l’orientation des fibres. Dès lors que l’on obtient une orientation dans le sens de l’efficacité mécanique, la résistance à la flexion est nettement améliorée.

  5. Archeologie sous-marine de l'ancienne Dwarka dans l'Okhamandal

    Gaur, A.S.

    ancient settlers since the Harappan times (3000 BC) and the oldest site discovered at Nageshwar on the northern shores of Okhamandal (Figure 1). The late phase of the Harappan civilization is noticed at Bet Dwarka Island about 5 km from Okha port. Dwarka...

  6. Thermal inactivation of Listeria monocytogenes and Salmonella spp. in sous-vide processed marinated chicken breast

    The heat resistance of a cocktail of five Salmonella strains and five L. monocytogenes strains was determined in teriyaki-marinated chicken breasts. Inoculated meat, packaged in bags, were completely immersed in a circulating water bath and cooked to a final temperature of 55, 57.5 or 60C in one h...

  7. Déchiffrer les mécanismes cognitifs et neuronaux qui sous-tendent l ...

    Ce projet cherche à comprendre les mécanismes cérébraux nécessaires pour permettre aux gens d'apprendre à percevoir les sons. Circuits neuronaux et apprentissage. L'équipe de recherche étudiera des personnes avec et sans formation musicale pour évaluer leur capacité d'apprendre des motifs sonores.

  8. L'urbanisation africaine sous les reflets du mirage de la mondialisation

    Reflection on "African urbanisation in the light of the mirage of globalization" focuses on the following main preoccupations: Characteristics of African urbanisation in the context of globalization; Response of social and cultural anthropology; and Perspectives offered to research and research-action? This paper raises ...

  9. Etude hydromecanique d'une fracture en cisaillement sous contrainte normale constante

    Lamontagne, Eric

    This research study deals with the effects of shear direction and injection flow rate on the flow directional anisotropy for a given normal stress. It presents experimental works on hydromechanical shear behaviour of a fracture under constant normal stress conditions that permits the characterisation of the intrinsic hydraulic transmissivity in relation with the directional anisotropy of the roughness morphology on the fracture surfaces. Tests were performed on mortar replicas of a natural fracture so that the fracture roughness and void space geometry were kept the same for each test. The experimental work program was performed through direct shear tests on the fracture replicas in four shear directions under four constant normal stress levels. The application of the normal stress was followed by several injections of fluid under constant flow rate. Then, for each defined shear displacement, several injections of fluid were done at different flow rate but under constant flow rate. The test results show that: (1) for the whole shear tests, the global intrinsic transmissivity is included within an enveloping zone of about one order of size. The transmissivity curves within the enveloping zone has a particularity to increase about two orders of size in the first millimetre of shear displacement and subsequently stabilised rapidly; (2) the highest dilatancy do not correspond necessarily with the highest intrinsic transmissivity so that, the behaviour of the global intrinsic transmissivity is not directly proportional to the fracture dilatancy during shear; (3) after the peak shear stress, the divergence is more marked between the global intrinsic transmissivity curves at various flow rate; (4) after peak shear strength and the beginning of asperity degradation, the gradual passage to residual friction shear behaviour causes a directional flow anisotropy and a reorientation of the flow chenalisation direction sub perpendicularly to the shear direction; (5) the anisotropy is not to develop equally between the two sense in the perpendicular direction to shear direction. In order to characterise the dynamics of the flow pattern in the fracture, a statistical analysis of the surfaces morphology of the fracture and the casting of void space geometry were performed before and after shear. A statistical analysis of asperity heights, on the global scale of the fracture surfaces, permits to characterise the fracture morphology and put in evidence a large morphological structure on which are superposed smaller asperities of variable dimensions. This large dimension structure generate a higher level landing occupying more than half of the fracture area. The study of the surfaces morphology of the fracture, performed with the geostatistical mean asperity heights variogram by direction before shearing, show the presence of two entangled morphologic structure families (28 and 15 mm). This same study done after shearing shows that the asperity degradation seems associated with the reduction of the global intrinsic transmissivity of the fracture. Finally, the void spaces morphology evaluated by casting techniques, during the shear tests, has permitted to verify the contacts evolution with the increasing shear displacement and visualised flow chenalisation during fracture shearing.

  10. à la capture de radicaux sous irradiation X à 1,5 keV

    Khalil Talat Tariq

    2016-01-01

    Full Text Available L’environnement chimique de l’ADN en situation biologique est complexe notam-ment en raison de la présence d’histones, protéines nucléaires, associées en quantité approximativement égales à l’ADN pour former la chromatine. Les histones possèdent de nombreux radicaux basiques arginine et lysine chargés positivement et dont la majorité se trouve sur les chaînes émergentes, l’ADN présente quant à lui des charges négatives sur ses groupements phosphates localisés tout au long de la double hélice. Dans cette étude, la complexité de la structure de la chromatine nucléaire est dans un premier temps mimée en solution aqueuse par la formation de complexes entre un ADN plasmidique sonde et les trois acides aminés basiques, Arg, His, Lys, qui, mis à part His, sont protonés au pH physiologique. Ces acides aminés libres en solution sont réputés être des capteurs efficaces de radicaux libres, notamment pour le radical hydroxyle, conférant ainsi un pouvoir protecteur vis-à-vis des effets indirects sur l’ADN en situation d’exposition aux rayonnements ionisants. A concentration fixée, les capacités de capture des acides aminés libres, σ, pour le radical hydroxyle sont typiquement les suivantes σHis ≈σArg > σLys (σLys ≈ 0,1 × σArg. Nous avons mesuré les taux de cassures simple brin par plasmide et par Gray (χ lors d’expositions de solutions aqueuses de complexes [acide aminé – ADN plasmidique] aux rayons X ultra-mous (1,5 keV. A concentrations égales, les trois acides aminés complexés et présents en large excès ne manifestent pas une capacité de protection de l’ADN proportionnelle à leur capacité de capture libre et en solution ; on trouve en effet des taux de cassures dans l’ordre suivant χHis > χArg > χLys (χLys ≈ 0,01 χArg. Après avoir détaillé le mode opératoire de ces mesures, nous analyserons sur des bases bibliographiques, les modes spécifiques d’interaction des acides aminés basiques avec l’ADN. La spécificité des liaisons de l’arginine avec l’ADN et plus particulièrement sa propension à être un ligand bidentate qui se lie aux bases (principalement G de l’ADN nous permet d’expliquer les taux de cassures simple brin particulièrement élevés observés avec Arg. Un mécanisme de transfert de radical intermoléculaire est suggéré pour Arg. Un raisonnement globalement similaire peut être tenu pour la lysine. Pour l’histidine, nous suggérons quelques voies possibles qui conduiraient à expliquer les taux de cassure anormalement élevés observés, mais cela demandera des expériences complémentaires.

  11. Jules Verne : un processus d’écriture sous contraintes

    Scheinhardt, Philippe

    2013-01-01

    Devenu célèbre, Jules Verne reçoit souvent la visite de journalistes qui l’interrogent aussi bien sur sa vie que sur son œuvre. De ces entretiens, il ressort que l’écrivain respecte comme tant d’autres des rites de création : habitudes de documentation, méthode de genèse littéraire. Ces rites, en écho à la contrainte externe du programme encyclopédique des Voyages extraordinaires, remplissent la fonction de contraintes internes au service de l’acte créateur. Ils renseignent sur les diverses p...

  12. Innovation en matière de biocarburants sous le signe de l'inclusion ...

    Ce projet favorisera une innovation en matière de biocarburants qui prend en compte tous les acteurs pertinents, dont les femmes vivant en milieu rural. Les chercheurs ... Des chercheurs appuyés par le CRDI parlent de leurs expériences au Comité sur les ONG lors du forum de la Commission de la condition de la femme.

  13. Évergétisme et sol public en Hispanie sous l’Empire

    Goffaux, Bertrand

    2009-01-01

    Cet article pose la question du statut des terrains sur lesquels étaient construits les édifices publics des villes hispaniques, à partir d’un commentaire de l’inscription d’Obulco (CIL, II2/7, 97) qui présente la formule solo empto ab re publica. Selon l’interprétation proposée, cette dernière indique que l’évergète acheta le terrain à la communauté, et non qu’il fut acquis par la ville. Cette lecture souligne le pragmatisme des autorités municipales et jette une nouvelle lumière sur les rel...

  14. Actinides and lanthanides under pressure: the pseudopotential approach; Actinides et terres rares sous pression: approche pseudopotentiel

    Richard, N

    2002-07-01

    In the Density Functional Theory Framework, the pseudopotential formalism offers a broader scope of study than other theoretical methods such as global relaxation of the parameters of the cell or ab initio molecular dynamics simulations. This method has been widely used to study light elements or transition metals but never to study f elements. We have generated two non local norm conserving Trouillier-Martins pseudopotentials (one in LDA and one in GGA) for the cerium. To check the validity of the pseudopotentials, we have calculated the equilibrium volume and the incompressibility modulus and compared our results to previous all-electron calculations. If the GGA and non linear core corrections are used, the equation of state is in a good agreement with the experimental equation of state. A static study of the previously proposed high pressure phases give a transitions fcc-a''(I)-bct. Using the pseudopotentials we have generated, an ab initio molecular dynamics simulation at constant pressure, in the region between 5 and 12 GPa where the stable phase of cerium is not well defined, lead us to predict that a centred monoclinic structure, as the a''(I) phase previously observed in some experiments, is the most stable phase. We have also generated pseudopotentials for the light actinides (Th, Pa, U and Np). We have study their phase transitions under pressure at zero temperature. We compared our results with all electron results. The structure parameters have always been relaxed in this study. And for the first time in pseudopotential calculation, the spin-orbit coupling has been taken into account. The curves describing the variation of the volume or the incompressibility modulus depending on the elements and the phase transitions are always in agreement with the one found in the all electron calculations. (author)

  15. Le nouvel accélérateur du CERN 1232 aimants sous la terre

    Du Brulle, Christian

    2005-01-01

    The LHC (Large Hadron Collider), whether the future particle accelerator of CERN, in Geneva, is now on its final assembling stage. Indeed, since Monday, the technicians and the engineers began to install under the ground the first magnets of this huge probing-matter machine in the ring of 27km under Switzerland and France

  16. Sous le pavage territorial, les réseaux de la Culture.

    Patrick Poncet

    2004-12-01

    Full Text Available «  L’offre artistique et patrimoniale en région, proximité et rayonnement culturel. » Décodons a priori . Offre : concept fondamental de l’économie ; art et patrimoine : binôme inspiré du Trivial pursuit ; en région : synonyme péjoratif de « en province »; proximité : notion géographique complexe ; rayonnement culturel : métaphore nucléaire appliquée aux Beaux Arts (s.l.. Le moins que l’on puisse dire, c’est que, par un tel titre, Fabrice Thuriot ...

  17. Innovation en matière de biocarburants sous le signe de l'inclusion ...

    Les préoccupations à l'égard de la sécurité énergétique ont poussé le gouvernement de l'Indonésie à publier plusieurs décrets présidentiels en 2005 et en 2006 pour faire la promotion d'un programme national de biocarburants reposant sur une huile végétale extraite des graines du pourghère (Jatropha curcas), une ...

  18. Tratamiento sous vide: cocción al vacio de pechuga de pollo

    Rocca, Rocío

    2010-01-01

    Esta tesis investiga las variaciones cuantitativas en el contenido de tiamina, riboflavina, niacina, sodio, calcio, hierro, fósforo y potasio en pechuga de pollo cocida al vacío y cocida en forma tradicional, considerando tradicional al método hervido; y conjuntamente valora el grado de aceptación general y de las características organolépticas de ambas preparaciones. Para conocer el contenido vitamínico y mineral del alimento, luego de sometido a ambas cocciones, se realiza...

  19. Le nouvel anneau du CERN rendra le sous-sol genevois radioactif

    Merckling, Nicolas

    2007-01-01

    As of next spring, the undergrounds in Geneva and Pays de Gex will radioactive around the biggest particle physics laboratory in the world. No danger for the population, say the scientists. (1/2 page)

  20. Acclimatation des vitro-plants de bananier ( Musa sp .) sous tunnels ...

    La banane contribue à la sécurité alimentaire et à l'augmentation du revenu des populations d'Afrique du centre et de l'ouest. Au Mali, la consommation de bananes devrait passer de 2,46 à 3,14 kg/habitant/an, ce qui engendrerait une augmentation de 16 000 tonnes d'ici l'an 2015. L'augmentation de la productivité des ...

  1. Methodes de decomposition pour la planification a moyen terme de la production hydroelectrique sous incertitude

    Carpentier, Pierre-Luc

    In this thesis, we consider the midterm production planning problem (MTPP) of hydroelectricity generation under uncertainty. The aim of this problem is to manage a set of interconnected hydroelectric reservoirs over several months. We are particularly interested in high dimensional reservoir systems that are operated by large hydroelectricity producers such as Hydro-Quebec. The aim of this thesis is to develop and evaluate different decomposition methods for solving the MTPP under uncertainty. This thesis is divided in three articles. The first article demonstrates the applicability of the progressive hedging algorithm (PHA), a scenario decomposition method, for managing hydroelectric reservoirs with multiannual storage capacity under highly variable operating conditions in Canada. The PHA is a classical stochastic optimization method designed to solve general multistage stochastic programs defined on a scenario tree. This method works by applying an augmented Lagrangian relaxation on non-anticipativity constraints (NACs) of the stochastic program. At each iteration of the PHA, a sequence of subproblems must be solved. Each subproblem corresponds to a deterministic version of the original stochastic program for a particular scenario in the scenario tree. Linear and a quadratic terms must be included in subproblem's objective functions to penalize any violation of NACs. An important limitation of the PHA is due to the fact that the number of subproblems to be solved and the number of penalty terms increase exponentially with the branching level in the tree. This phenomenon can make the application of the PHA particularly difficult when the scenario tree covers several tens of time periods. Another important limitation of the PHA is caused by the fact that the difficulty level of NACs generally increases as the variability of scenarios increases. Consequently, applying the PHA becomes particularly challenging in hydroclimatic regions that are characterized by a high level of seasonal and interannual variability. These two types of limitations can slow down the algorithm's convergence rate and increase the running time per iteration. In this study, we apply the PHA on Hydro-Quebec's power system over a 92-week planning horizon. Hydrologic uncertainty is represented by a scenario tree containing 6 branching stages and 1,635 nodes. The PHA is especially well-suited for this particular application given that the company already possess a deterministic optimization model to solve the MTPP. The second article presents a new approach which enhances the performance of the PHA for solving general Mstochastic programs. The proposed method works by applying a multiscenario decomposition scheme on the stochastic program. Our heuristic method aims at constructing an optimal partition of the scenario set by minimizing the number of NACs on which an augmented Lagrangean relaxation must be applied. Each subproblem is a stochastic program defined on a group of scenarios. NACs linking scenarios sharing a common group are represented implicitly in subproblems by using a group-node system index instead of the traditional scenario-time index system. Only the NACs that link the different scenario groups are represented explicitly and relaxed. The proposed method is evaluated numerically on an hydroelectric reservoir management problem in Quebec. The results of this experiment show that our method has several advantages. Firstly, it allows to reduce the running time per iteration of the PHA by reducing the number of penalty terms that are included in the objective function and by reducing the amount of duplicated constraints and variables. In turn, this allows to reduce the running time per iteration of the algorithm. Secondly, it allows to increase the algorithm's convergence rate by reducing the variability of intermediary solutions at duplicated tree nodes. Thirdly, our approach reduces the amount of random-access memory (RAM) required for storing Lagrange multipliers associated with relaxed NACs. The third article presents an extension of the L-Shaped method designed specifically for managing hydroelectric reservoir systems with a high storage capacity. The method proposed in this paper enables to consider a higher branching level than conventional decomposition method enables. To achieve this, we assume that the stochastic process driving random parameters has a memory loss at time period t = tau. Because of this assumption, the scenario tree possess a special symmetrical structure at the second stage (t > tau). We exploit this feature using a two-stage Benders decomposition method. Each decomposition stage covers several consecutive time periods. The proposed method works by constructing a convex and piecewise linear recourse function that represents the expected cost at the second stage in the master problem. The subproblem and the master problem are stochastic program defined on scenario subtrees and can be solved using a conventional decomposition method or directly. We test the proposed method on an hydroelectric power system in Quebec over a 104-week planning horizon. (Abstract shortened by UMI.).

  2. Le risque hydrologique : du concept à sa gestion, Alain GIRET, sous la direction de

    Jean-Louis Ballais

    2009-11-01

    Full Text Available Cet ouvrage constitue les actes du colloque Les Rencontres de Géo. 13, organisé à l'Université Paris 13, le 28 octobre 2005. La courte introduction d'Alain GIRET (2 p. permet à l'organisateur du colloque de préciser la conception du risque hydrologique de ce colloque "Le cadre conceptuel se réduit aux seuls extrêmes hydrologiques fluviaux : les étiages et les inondations, écartant problèmes de pollution et de qualité des eaux".La section 1 regroupe concept et processus. François CHAGNAUD s'i...

  3. Irradiation Behaviour of Uranium Carbide Fuels; Comportement des carbures d'uranium sous l’effet de l'irradiation; ПОВЕДЕНИЕ УРАНО-КАРБИДНОГО ТОПЛИВА ПРИ ОБЛУЧЕНИИ; Comportamiento de los combustibles de carburo de uranio frente a la irradiación

    Sinizer, D. I.; Webb, B. A.; Berger, S. [Atomics International, Canoga Park, CA (United States)

    1963-08-15

    25 000 MWj/t d'U, pour une température au centre de 1700°F (926°C). Ce chiffre est obtenu par extrapolation des données expérimentales pour des taux de combustion allant jusqu'à 15 000 MWj/t d'U, à la même température. Dans des expériences en pile et hors pile, on a constaté qu'une certaine quantité de carbone du combustible hyperstoechiométriquè UC passe, à travers le lien de sodium, dans la gaine en acier inoxydable. De l'avis des auteurs, rien ne prouve que le processus de transfert du carbone soit accéléré par l'irradiation. Deux mécanismes semblent entrer en jeu simultanément. A des températures supérieures à 1000°F(540°C), la phase UC{sub 2} est attaquée en préférence par le sodium ou le NaK; de ce fait, il y a perte d'un atome de carbone, qui se dissout dans le Na, et transformation de UC{sub 2} tétragonal à mailles centrées en UC cubique à faces centrées. Il reste des lacunes dans les sites précédemment occupés par la phase UC{sub 2} à faible densité. Ce processus est très net dans les essais hors pile de compatibilité isothermique: il permet de déterminer le transfert de carbone dans la gaine. Sous l'effet de l’irradiation, on peut observer dans la phase UC une diffusion qui a pour résultât la«guérison»des lacunes dans les anciens sites de UC{sub 2}. On pense que cette guérison est accélérée par l'effort de compression du combustible, résultant du gradient de température maximum pendant l'irradiation. Il en résulte une microstructure en phase simple, sans lacunes, dans la région décarburée du combustible initialement hyperstoechiométrique. Aucun transfert de carbone n'intervient pour le UC hypo- stoechiométrique. Dans les expériences en pile comme dans celles hors pilé, le carbone détaché du combustible UC hyperstoechiométrique traverse aisément le lien de Na, pour carburer la gaine en acier inoxydable. Ce transfert impose peut-être une limitation dans la composition du combustible devant

  4. Theoretical galactic cosmic ray electron spectrum obtained for sources of varying geometry; Spectre theorique des electrons du rayonnement cosmique dans la galaxie obtenu pour des sources a geometrie variable

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

    1969-07-01

    Jokipii and Meyer have recently obtained an electron density energy spectrum of the cosmic rays, originating in the Galaxy, using integral solutions of the steady state transfer equations, by considering a circular cylindric galactic disc as source and approximating the resulting fourth order integral. In this report, we present general results, obtained by using an arbitrary circular cylindric source, without restricting ourselves to the galactic disc. The integrals are treated exactly. The conclusions of Jokipii and Meyer form special cases of these results. We also obtain an exponential energy variation which, at the moment, is not observed experimentally. The second part of this work deals with more complicated, but perhaps more realistic models of elliptic cylindric and ellipsoidal galactic disc sources. One may also note that a very large source concentrated in a very small region gives a spectrum not unlike that for a small source distributed throughout a large volume. Finally, it may be remarked that the model adopted is much less restrictive than the artificial conception of 'leakage time' followed by other workers. (author) [French] Jokipii et Meyer ont dernierement obtenu un spectre d'energie pour les electrons galactiques dans le rayonnement cosmique, en utilisant les solutions des equations de transfert, a l'etat stationnaire, ces dernieres etant sous forme d'integrales, en prenant une source completement diffusee dans le disque galactique, celui-ci etant hypothetiquement choisi comme circulaire et cylindrique et en faisant une approximation sur l'integrale du quatrieme degre. Dans ce rapport, nous presentons des resultats generaux obtenus en faisant appel a une source, diffusee dans un cylindre circulaire, arbitrairement choisi, c'est-a-dire sans nous restreindre au disque galactique comme source. Les integrales sont traitees d'une maniere exacte. Les conclusions de Jokipii et Meyer constituent des cas speciaux des resultats precedents. Nous obtenons

  5. Greedy algorithms for high-dimensional non-symmetric linear problems***

    Cancès E.

    2013-12-01

    Full Text Available In this article, we present a family of numerical approaches to solve high-dimensional linear non-symmetric problems. The principle of these methods is to approximate a function which depends on a large number of variates by a sum of tensor product functions, each term of which is iteratively computed via a greedy algorithm ? . There exists a good theoretical framework for these methods in the case of (linear and nonlinear symmetric elliptic problems. However, the convergence results are not valid any more as soon as the problems under consideration are not symmetric. We present here a review of the main algorithms proposed in the literature to circumvent this difficulty, together with some new approaches. The theoretical convergence results and the practical implementation of these algorithms are discussed. Their behaviors are illustrated through some numerical examples. Dans cet article, nous présentons une famille de méthodes numériques pour résoudre des problèmes linéaires non symétriques en grande dimension. Le principe de ces approches est de représenter une fonction dépendant d’un grand nombre de variables sous la forme d’une somme de fonctions produit tensoriel, dont chaque terme est calculé itérativement via un algorithme glouton ? . Ces méthodes possèdent de bonnes propriétés théoriques dans le cas de problèmes elliptiques symétriques (linéaires ou non linéaires, mais celles-ci ne sont plus valables dès lors que les problèmes considérés ne sont plus symétriques. Nous présentons une revue des principaux algorithmes proposés dans la littérature pour contourner cette difficulté ainsi que de nouvelles approches que nous proposons. Les résultats de convergence théoriques et la mise en oeuvre pratique de ces algorithmes sont détaillés et leur comportement est illustré au travers d’exemples numériques.

  6. Renewable energies dossier. The early beginnings of a change in the building trade. Outstanding evolutions presented at ISH 2001. A development still bounded by the economic sustain of the government. Something new under the sun. Looking for alternate solutions for air-conditioning. A photovoltaic project for developing countries. The solar absorption improves the Banyuls wine. A thermal solar collector for the production of sanitary hot water in Ile-de-France; Dossier energies renouvelables. Les premices d'un mouvement dans le batiment. Des evolutions marquantes presentees a ISH 2001. Un developpemnt encore lie au soutien economique de l'etat. Du nouveau sous le soleil. A la recherche de solutions alternatives pour la climatisation. Un projet photovoltaique pour les pays en voie de developpement. L'absorption solaire bonifie le banyuls. Un capteur solaire thermique pour l'ECS en Ile-de-France

    Sappa, F.; Grumel, N.; Haentjens, H.

    2001-07-01

    The fight against greenhouse gas emissions implies to favor the development and use of renewable energies and to reduce the consumption of fossil fuels. The professionals of the building trade are of course concerned by such actions but unfortunately only few space heating/cooling or air-conditioning installations use renewable energies. In France, only one solar absorption air-conditioning installation exists (at Banyuls, Pyrenees Orientales) and the Bordeaux airport is one of the only buildings supplied with a tri-generation unit. This dossier makes a prospective analysis of the existing techniques that would be used in tomorrow's air-conditioning. It comprises 8 articles dealing with: the early beginnings of the use of renewable energies in the building trade and the inventory of existing techniques: solar thermal, cogeneration, tri-generation (electricity, heat and coldness), fuel cells (electrochemical reaction); the outstanding products presented at Frankfurt during the 2001 edition of the ISH exhibition (absorption heat pumps, heat pump with zeolite and water as refrigerant, solar heaters, hybrid systems, condensation boilers, fuel cells..); the bad competitiveness of renewable energies and the necessary financial sustain of the government; the start-up of the 'sun plan' program by the French agency of environment and energy mastery (Ademe) for the development of solar thermal energy in the residential sector; the 'know-how technical notes' edited by the scientific and technical committee of environment industries (Costic) for the development of low energy consumption air-conditioning processes (dry cooling, evaporation cooling, recovery of heat losses etc..); the project of development of photovoltaic cooling systems for developing countries (evaporative cooling or buried pipes); the unique French solar wine ageing cellar of Banyuls (3500 m{sup 2}, 15000 m{sup 3}, 3 levels); the thermal solar collector of the Quality Hotel of Rosny-sous

  7. Untitled

    Hamburg 15. (1945) 211–261 -. Deligne P and Mumford D, The irreducibility of the space of moduli of a given genus, Publ. Math. IHES 36 (1969) 75–110. Deligne P and Rapoport M, Les schémas de modules de courbes elliptiques, Modular functions of one variables II, Springer Lecture Notes in Math. 349 (1973) 143–316.

  8. The Behaviour of Various Graphites under Neutron Irradiation; Comportement de divers graphites sous l'effet de l'irradiation neutronique; ПОВЕДЕНИЕ РАЗЛИЧНЫХ ГРАФИТОВ ПОД ДЕЙСТВИЕМ НЕЙТРОННОГО ОБЛУЧЕНИЯ; Efectos de la irradiación neutrónica sobre diversos tipos de grafitos

    Fitzer, E.; Vohler, O. [Siemens-Planiawerke AG für Kohlefabrikate, Meitingen bei Augsburg, Federal Republic of Germany (Germany)

    1963-08-15

    paper is concerned with the correlation between the Wigner growth and the shape of the sample. The results presented here are compared with those reported in the literature, and it is shown that the absolute value of the Wigner growth depends on the shape of the irradiated graphite sample in such a manner that the specimens with the greatest length- to- width ratio show the greatest relative change in length after irradiation. In the last section the results of irradiations of the same graphite types in three different reactors, FRM, EL. a and GETR, are compared. The reactors differ very much in the neutron spectrum of their irradiation channels, and on the basis of the measured radiation damages the neutron doses can be estimated. It was found that in a test hole in the FRM the same irradiation damage is caused by a dose of 1 x 10{sup 19} n/cm{sup 2} as in the core of the GETR at 1 x 10{sup 21}n/cm{sup 2}. In the EL.3, the equivalent degree of damage could not be achieved because of the low neutron energy at the irradiation channel. (author) [French] Depuis un certain nombre d'années, la modification des propriétés du graphite sous l'effet de l'irradiation neutronique - question très importante dans les études de réacteurs - fait l'objet de recherches approfondies, dont les résultats ont été expósés en détail par plusieurs auteurs. Ces expériences sur l'irradiation visaient à déterminer quantitativement les modifications des propriétés en fonction du nombre de neutrons par cm{sup 2} et de Ja température. Le programme de recherche sur l'irradiation, entrepris à l'initiative du Ministère des affaires atomiques de la République fédérale d'Allemagne, avait pour objet d'étudier le comportement de toute une gamme de graphites pour réacteurs sous irradiation contrôlée. Dans la première partie du mémoire, les auteurs indiquent quels ont été les dommages causés par les rayonnements, selon le type de graphite artificiel. Les types de graphite ne

  9. Argent de l'Etat et politique: La sortie difficile de l'État rentier en Égypte sous Moubarak : La sortie difficile de l'Etat rentier en Egypte sous Moubarek

    Soliman, Samer

    2004-01-01

    This book is a political economy study that tackles the relationship between public finance and politics in Egypt during the period 1981-2003. It analyzes how the authoritarian regime of Hosni Moubarak has adapted to its fiscal crisis and how this crisis has affected the relationships between state and society and between the different parts and levels of the state. Political economy studies on Egypt have maintained that the reproduction of authoritarianism in this country has mainly been ach...

  10. Amélioration des propriétés physiques et chimiques du sol sous l ...

    SARAH

    28 févr. 2014 ... RESUME. Objectifs : Cette étude a été conduite au cours de la saison culturale 2012-2013 sur un ferralsol de la ferme. Kasapa dans la région de Lubumbashi en vue d'évaluer les effets des doses combinées des fumiers des poules et des engrais minéraux sur le rendement de maïs (Zea mays Var Unilu) ...

  11. Poucet, B., La liberté sous contrat. Une histoire de l’enseignement privé

    Rozenn Rouillard

    2011-06-01

    Full Text Available En France, l’histoire du système scolaire ne peut être appréhendée dans sa globalité sans porter un regard attentif et aiguisé sur celle de l’enseignement privé, comme notamment celui de Bruno Poucet depuis quelques années. Son dernier ouvrage s’attache à retracer les traits historiques du secteur d’enseignement associé à l’État, en l’occurrence catholique, avec une question centrale qui le guide : comment expliquer le présent par le passé ? Le résultat émane du travail imbriqué de l’historie...

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

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

    2003-07-01

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

  13. Recherche de propriétés de fatigue dommages et dilatance de roche sous chargement cyclique discontinu

    Fan , Jinyang

    2017-01-01

    Since the salt cavern storage of natural gas and compressed air plays a critical role in ensuring the energy supply and adjusting the seasonal imbalance of power, China government has been constructing numerous new storages in recent years. Because of the seasonal of the seasonal variations of the gas/air pressure, the storages undergo cyclic loading, which causes rock fatigue and induces the associated safety and environmental hazards. The investigation of the discontinuous fatigue of salt u...

  14. L’expertise des risques sanitaires : entre indépendance et mise sous tutelle ?

    Goldberg, Marcel

    2009-01-01

    À la suite de diverses crises sanitaires majeures, la loi du 1er juillet 1998 sur la sécurité et la veille sanitaire a conduit notamment à la création de l’Institut de veille sanitaire (InVS), organisme d’État, chargé d’une mission de service public pour l’évaluation des risques pour la santé. Si observation, surveillance, veille, alerte en étaient les maîtres mots, restait à mettre en œuvre la séparation de l’évaluation et de la gestion des risques pour la santé. After different major med...

  15. The energy in all states: data, constraints, stakes; L'energie sous toutes ses formes: donnees, contraintes, enjeux

    Balian, R [Academie des Sciences, 92 - Gif sur Yvette (France); Combarnous, M [Bordeaux-1 Univ., LEPT-ENSAM, 33 - Talence (France); Lucas, J; Fauvarque, J F [Conservatoire National des Arts et Metiers (CNAM), 75 - Paris (France); Madet, D [Electricite de France (EDF), 75 - Paris (France); Bal, J L [Agence de l' Environnement et de la Maitrise de l' Energie, ADEME, 75 - Paris (France); Jourde, P [CEA Cadarache, GENEC, 13 - Saint-Paul-lez-Durance (France); Tissot, B [Commission Nationale d' Evaluation, 75 - Paris (France); Leconte, Ph [CEA Saclay, Dir. du Developpement et de l' Innovation Nucleares DDIN, 91 - Gif Sur Yvette (France); Doubre, H [Paris-11 Univ., IN2P3/CNRS, 91 - Orsay (France); Alleau, Th [Association Francaise de l' Hydrogene, AFH2, 75 - Paris (France); Durup, G [Mining Research Institute (United States); Le Treut, H [Ecole Nationale Superieure, 75 - Paris (France); Tubiana, M [Institut Gustave Roussy, 94 - Villejuif (France); [Centre Antoine Beclere, Paris (France); Masse, R [Office de Protection contre les Rayonnements Ionisants, 78 - le Vesinet (France); Lebot, B [Agence Internationale de l' Energie, 75 - Paris (France); Babusiaux, D [Institut Francais du Petrole (IFP), 92 - Rueil-Malmaison (France); Saab, A E [Electricite de France (EDF), 75 - Paris (France)

    2002-07-01

    This documents brings together papers presented at the physics summer school of august 2001 on the energy. The following topics are discussed: the constraints bound to the physics and the scales, the renewable energies, the future of the nuclear energy and the fossil energies, the energy storage problems, the environmental and sanitary aspects, the energy mastership and economy. (A.L.B.)

  16. Underwater search of ancient Dwarka in Okhamandal (Archeologie sous-marine de l'ancienne Dwarka dans l'Okhamandal)

    Gaur, A.S.

    , ailleurs rocheux et escarpi, ce qui fait que les ancres se rompent ou dirivent sur les fonds. D De son cat&, Ptolimie mentionne Barake comme une ile dans le golfe de Kanthi, qui a tti identifit comme le golfe de Kachchh. I1 est donc fort pro- bable que...

  17. Stereotactic radiotherapy by cyberknife of sub-diaphragm digestive tumors; Radiotherapie stereotaxique par Cyberknife des tumeurs digestives sous diaphragmatiques

    Taste, H.; Peiffert, D.; Beckendorf, V.; Marchesi, V.; Noel, A. [Centre Alexis-Vautrin, 54 - Vandoeuvre-les-Nancy (France)

    2009-10-15

    The stereotactic radiotherapy is a low toxic, efficient therapy offering a supplementary curative alternative, with promising first results, confirmed by literature. ts indications, its place in the therapy strategy stay to determine in the clinical research program. (N.C.)

  18. A method of sub-critical experimentation, 'the neutrostat'; Une methode d'experimentation sous critique 'le neutrostat'

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

    1958-07-01

    The method proposed is designed for the study of neutronic properties of a sample (its material buckling, for example) and consists in submitting the sample to uniform surface density irradiation, its surface being a sphere or a cylinder which is supposed, temporarily, to be infinite. Neutron density in the sample will thus be uniform if its laplacian is nil: any curve in the distribution clearly indicating its absorbent or multiplying properties. In the case of a sample with multiplying power, density is identical to that in an active core, thus measurement of buckling will be free from considerable systematic error causes. The thermic equivalent of this type of irradiation would be a thermostat with an external heat source distributed uniformly over its surface: its temperature would be uniform. It is this analogy that has led us to baptize it the 'Neutrostat'. (author)Fren. [French] En vue d'etudier les proprietes neutroniques d'un milieu (son laplacien 'matiere' par exemple), la methode proposee consiste a le soumettre a des conditions d'irradiation uniforme sur sa surface, celle-ci ayant la forme d'une sphere ou d'un cylindre que nous supposons provisoirement infini. Les neutrons s'y trouvent alors repartis avec une densite uniforme si le milieu est un diffuseur pur. Toute courbure de cette repartition sera un indice sensible de ses proprietes absorbantes ou multiplicatrices. Dans le cas d'un milieu multiplicateur, la repartition est identique a celle qui regne au milieu d'une pile critique et nous verrons que la mesure du laplacien est alors exempte de causes d'erreurs systematiques importantes. L'equivalent thermique d'un tel mode d'irradiation serait un dispositif thermostatique dont la source de chaleur externe serait repartie uniformement sur la surface: il y regnerait une temperature uniforme. C'est cette analogie qui nous a guides dans le choix du vocable propose dans le titre: 'Neutrostat'. (auteur)

  19. Production durable de légumes sous-utilisés en vue d'améliorer la ...

    Manitoba universities and project partners awarded $6.4-Million from Canadian International Food Security Research Fund for international research. Download PDF. Reports. Sustainable Production and Utilization of Underutilized Nigerian Vegetables to Enhance Rural Food Security : Final Technical Report (March 2011 ...

  20. The electric charge of the aerosols under gamma radiation; La charge electrique des aerosols sous irradiation gamma

    Gensdarmes, F.; Cetier, P.; Boulaud, D. [CEA/Saclay, Inst. de Protection et de Surete Nucleaire, IPSN/DPEA/SERAC, 91 - Gif-sur-Yvette (France); Renoux, A. [Paris-12 Univ., Lab. de Physique des Aerosols et de Transfert des Contaminations, 94 - Creteil (France)

    2000-07-01

    During a PWR type reactor accident, the gamma radiation may create a high ionized atmosphere. In such a situation the aerosols properties knowledge is useful to simulate the particles transport and deposit in the enclosed. The aim of this study is to determine the aerosol charges distribution in a high ionized medium, in function of the ionic properties of the medium. (A.L.B.)

  1. Évaluation de la productivité du maïs ( Zea mays L.) sous ...

    Conclusion et principales applications de la recherche: L'application des biomasses T. diversifolia et E. abyssinica en combinaison organo-minérale sur une culture de maïs démontre jouer un rôle multiple sur la physique, la chimie et la biologie du sol avec comme conséquence une augmentation du rendement de l'ordre ...

  2. The energy in all states: data, constraints, stakes; L'energie sous toutes ses formes: donnees, contraintes, enjeux

    Balian, R. [Academie des Sciences, 92 - Gif sur Yvette (France); Combarnous, M. [Bordeaux-1 Univ., LEPT-ENSAM, 33 - Talence (France); Lucas, J.; Fauvarque, J.F. [Conservatoire National des Arts et Metiers (CNAM), 75 - Paris (France); Madet, D. [Electricite de France (EDF), 75 - Paris (France); Bal, J.L. [Agence de l' Environnement et de la Maitrise de l' Energie, ADEME, 75 - Paris (France); Jourde, P. [CEA Cadarache, GENEC, 13 - Saint-Paul-lez-Durance (France); Tissot, B. [Commission Nationale d' Evaluation, 75 - Paris (France); Leconte, Ph. [CEA Saclay, Dir. du Developpement et de l' Innovation Nucleares DDIN, 91 - Gif Sur Yvette (France); Doubre, H. [Paris-11 Univ., IN2P3/CNRS, 91 - Orsay (France); Alleau, Th. [Association Francaise de l' Hydrogene, AFH2, 75 - Paris (France); Durup, G. [Mining Research Institute (United States); Le Treut, H. [Ecole Nationale Superieure, 75 - Paris (France); Tubiana, M. [Institut Gustave Roussy, 94 - Villejuif (France)]|[Centre Antoine Beclere, Paris (France); Masse, R. [Office de Protection contre les Rayonnements Ionisants, 78 - le Vesinet (France); Lebot, B. [Agence Internationale de l' Energie, 75 - Paris (France); Babusiaux, D. [Institut Francais du Petrole (IFP), 92 - Rueil-Malmaison (France); Saab, A.E. [Electricite de France (EDF), 75 - Paris (France)

    2002-07-01

    This documents brings together papers presented at the physics summer school of august 2001 on the energy. The following topics are discussed: the constraints bound to the physics and the scales, the renewable energies, the future of the nuclear energy and the fossil energies, the energy storage problems, the environmental and sanitary aspects, the energy mastership and economy. (A.L.B.)

  3. Diversité floristique sous canopée en plantation forestière de Mangombe-Edea (Cameroun

    Makombu, G.

    2010-01-01

    Full Text Available Floristic diversity under canopy in forest plantation of Mangombe-Edea (Cameroon. Trees plantation of Mangombe is situated in rain forest of low altitude. Six plots among which one of Mansonia altissima (A.Chev. A.Chev., 2 of Lovoa trichilioides Harms, 3 of Terminalia ivorensis A.Chev. and one perturbed natural forest are concerned by this study. The work consisted to the evaluation of the floristic diversity under canopy in order to appreciate the influence of forest plantation on natural regeneration. A total of 26 families, 42 genders and 46 species were censured. Meliaceae and Apocynaceae are present in all the plots. In plot one of T. ivorensis, M. altissima and natural forest, the low value of equitability of Pielou traduces the dominance of flora by few species and the transitory situation of the ecosystem. On contrary the rest of plots present a good repartition of individuals among the species. One can notice a weak organization of the ecologic system in M. altissima plot, this corresponds to favourable conditions of environment for installation of many species represented by a few number of individuals. Shannon indices, relatively low in plot one of T. ivorensis characterize an ecosystem where one species is dominant. Globally, the regeneration under canopy is reconstituted progressively and remains less diversified than the nearest natural forest. Creation of genetic pool through selective entertainment under canopy will permit polycyclic management of plots for sustainable production of wood.

  4. Structural modifications under reactive atmosphere of cobalt catalysts; Modifications structurales sous atmospheres reactionnelles de catalyseurs a base de cobalt

    Ducreux, O.

    1999-11-23

    The purpose of this work was to develop in situ methods under reactive dynamic conditions (XRD and Fourier transform infrared spectroscopy) to describe the active phase structure in order to understand Fischer-Tropsch catalyst behaviour and improve the natural gas conversion process performance. Experiments were designed to correlate structural modifications with catalytic results. The effect of ruthenium used as a promoter has also been studied. The impregnation process increases cobalt-support interaction. The presence of ruthenium promoter reduces this effect. Interactions between Co{sub 3}O{sub 4} oxide and support play an important role in the reducibility of cobalt and in the resulting metal structure. This in turn strongly influences the catalytic behaviour. Our results show a close correlation between structure modification and reactivity in the systems studied. Cobalt metal and CO can react to form a carbide Co{sub 2}C under conditions close to those of the Fischer-Tropsch synthesis. This carbide formation seems to be related to a deactivation process. The presence of interstitial carbon formed by dissociation of CO is proposed as a key to understanding the mechanism of the Fischer-Tropsch reaction. A specific catalyst activation treatment was developed to increase the catalytic activity. This work permits correlation of materials structure with their chemical properties and demonstrates the contribution of in situ physico-chemical characterisation methods to describe solids under reactive atmosphere. (author)

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

    Mokhtari, Mohand

    2012-01-01

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

  6. Gestion des apports organiques en systèmes de culture maraîchers sous abri

    Bressoud, miss Frédérique; Parès, miss Laure

    2003-01-01

    Afin d’améliorer les pratiques de fertilisation en maraîchage biologique, la minéralisation de 2 types de composts est évaluée par différentes méthodes sur plusieurs cultures salade-tomate successives. Les premiers résultats montrent une contribution de ces composts à l’alimentation de la culture estivale, sans incidence sur les rendements récoltés.

  7. Le CERN enverra un faisceau de neutrinos sous les Alpes vers un détecteur distant de 730 km

    CERN Press Office. Geneva

    1999-01-01

    CERN is collaborating with the National Institute of Nuclear Physics (INFN) in Italy to send a beam of neutrinos through the earth, under the mountains from Geneva in Switzerland to the Gran Sasso laboratory in central Italy, 730 km away. The experiments will shed light on the possibility that neutrinos have mass and exhibit the exotic property of transforming from one kind into another.

  8. Une activité sous contrôle : l’esclavage à Malte à l’époque moderne

    Brogini, Anne

    2014-01-01

    La pratique de l’esclavage n’est pas nouvelle pour les Hospitaliers de Saint-Jean de Jérusalem à l’époque moderne, ni pour l’île de Malte. Mais l’essor formidable de l’activité corsaire aux xvie et xviie siècles transforme Malte en plaque-tournante de l’esclavage méditerranéen. L’arrivée massive d’esclaves non-chrétiens, puis leur résidence dans le port conduit l’Ordre de Malte à structurer et à règlementer progressivement la pratique corsaire et commerciale (modes et lieux de capture, lieux ...

  9. Recherche sur les sous-declarations de décés, Saint Marc, Haiti, 2012

    Stela Nazareth Meneghel

    2014-11-01

    Full Text Available Ce travail se réfère à une étude exploratoire menée dans la ville de Saint Marc, une commune d'environ 257,863 habitants en 2012, localisée dans le département d'Artibonite/Haïti. L'objectif est rechercher le flux d'informations concernant le système de mortalité et l'existence de non-déclarations de décès. Les décès survenus dans le mois de janvier 2013 ont fait l'objet d'une enquête dans cinq institutions de la ville de Saint Marc: l'Hôpital Saint Nicolas (HSN, la Mairie, le Bureau d'État Civil (BEC, le Cimetière et la Cathédrale. L'hôpital a été l'institution où l'on a rencontré le plus grand nombre de décès enregistrés. On a procédé au comptage des décès, à partir de la liste nominale des registres hospitaliers, en ajoutant les décè...

  10. Soil clean up by vapour extraction: parametrical study; Depollution des sols par extraction sous pression reduite: etude de quelques parametres

    Dutheil, C.

    2003-05-15

    Soil vapour extraction is a treatment process for soils polluted by volatile organic compounds. Its principle relies on the circulation of gaseous flow in soil by the application of a depression of some hundreds milli-bars. A parametrical study has been led on a soil artificially polluted by tri-chloro-ethene. It shows that the gaseous flow rate has a slight influence on pollutants extraction yield. This is due to rate limited mass transfer processes. Soil moisture plays a negative role on treatment efficiency because of the reduction of the porosity available for the gas circulation. Tests have been performed on a soil polluted by a complex mixture of organic pollutants to elaborate a methodology of technical feasibility assessment. This methodology aims at identifying and limiting risks of site rehabilitation failure. Tests results show that soil vapour extraction was inadequate to treat the soil tested in this study because of the strong affinity between a dense organic phase (grease) and chlorinated solvents. (author)

  11. Hortisol - Including energetic considerations into greenhouse cultivation; Hortisol - Integration des processus energetiques dans les cultures sous abris

    Bonvin, M.; Morand, G.; Reist, A.

    2005-07-01

    The goal of the project is to optimize the utilization of the energetic and financial resources required for the commercial production of biomass in greenhouses though the development of a suitable computer simulation program. In a first step, the existing literature on the subject has been collected and reviewed with special emphasis on the culture of tomatoes. The main influencing parameters are: the temperature within the greenhouse and its time variations, the magnitude and the dynamics of thermal energy flows, the concentration of carbon dioxide, the lighting (natural and artificial), and the relative humidity. Considering all factors, a mathematical model has been worked out that quantifies all energy transfers through the outer surface of the greenhouse. A first version of a computer simulation program for the planning and operation of a greenhouse cultivating tomatoes has been developed. It shall be validated and refined in the forthcoming year (2006)

  12. Hortisol - Integration of energy-processes in greenhouses; Hortisol - Integration des processus energetiques dans les cultures sous abris

    Bonvin, M.; Morand, G. [Haute Ecole valaisanne, Sion (Switzerland); Reist, A. [Antoine Reist, Vetroz (Switzerland)

    2006-07-01

    This final report published by the Swiss Federal Office of Energy (SFOE) takes a look at Hortisol - a simulation aid for growers of tomatoes. This simulation aid not only takes various energy aspects such as heat, humidity, carbon dioxide and artificial light into account, but also the agricultural aspects of tomato cultures. The paper describes how planners can use the tool to simulate various situations and their effects on the growing of tomatoes and on the amount of energy used. The models and rules used in the simulation are presented. The structure of the simulation software and its validation are discussed. Appendices present the theoretical basis of the tool and screen-shots.

  13. Modelisation, conception et simulation des performances d'un collecteur solaire aeraulique a tubes sous vide en milieu nordique

    Paradis, Pierre-Luc

    The global energy consumption is still increasing year after year even if different initiatives are set up to decrease fossil fuel dependency. In Canada 80% of the energy is used for space heating and domestic hot water heating in residential sector. This heat could be provided by solar thermal technologies despite few difficulties originating from the cold climate. The aim of this project is to design a solar evacuated tube thermal collector using air as the working fluid. Firstly, needs and specifications of the product are established in a clear way. Then, three concepts of collector are presented. The first one relies on the standard evacuated tube. The second one uses a new technology of tubes; both sides are open. The third one uses heat pipe to extract the heat from the tubes. Based on the needs and specification as criteria, the concept involving tubes with both sides open has been selected as the best idea. In order to simulate the performances of the collector, a model of the heat exchanges in an evacuated tube was developed in 4 steps. The first step is a model in steady state intended to calculate the stagnation temperature of the tube for a fixed solar radiation, outside temperature and wind speed. As a second step, the model is generalised to transient condition in order to validate it with an experimental setup. A root mean square error of 2% is then calculated. The two remainder steps are intended to calculate the temperature of airflow leaving the tube. In the same way, a first model in steady state is developed and then generalised to the transient mode. Then, the validation with an experimental setup gave a difference of 0.2% for the root mean square error. Finally, a preindustrial prototype intended to work in open loop for preheating of fresh air is presented. During the project, explosion of the both sides open evacuated tube in overheating condition blocked the construction of a real prototype for the test. Different path for further work are also identified. One of these is in relation with CFD simulation of the uniformity of the airflow inside of the collector. Another one is the analysis of the design with a design of experiment plan.

  14. Caractéristiques physiques de la production du melon cantaloup Cucumis melo L., cultivé sous serre

    Hannachi, C.

    1994-01-01

    Full Text Available Physical Characteristics Of Muskmelon Production, Cucumis melo L., Cultivated Under Greenhouse- Tunisia. Seven varieties of cantaloup muskmelon (Pancha, Sugdor, Supersprint, F^6802, Gallicum, Polidor, Pallas were cultivated in plastic house and tested for yield and fruit quality (fruit weight, index of refraction, thickness of flesh. Supersprint, Pancha and Sugdor were the more productive varieties. Their early yield represents 61 %, 62 %> and 53 %> of total yield : 4, 2 ; 5, 2 and 5, 7 kg/m2 respectively. Fruits had a commercial weight of more than 500 g and an acceptable gustative quality ; IR> 10. Fruit weight was positively correlated with viable seed number (pancha : IR was appreciated for Pancha, Sugdor and F^802 (IR> 12. The flesh of these three varieties was well developped, and it was probably influenced by the important seed number (523-610 seeds/fruit. It was 3 cm wide and 6 times as thick as the cortex (0, 5 cm. Pancha was significantly distinguished from others by the fruit number (6 fruits/plant. The introduction of honey bees may improve pollination of flowers and allowed to exploit better its potentialities.

  15. La Maison du Roi sous Louis XIV, une troupe d’élite. Étude tactique

    Chauviré, Frédéric

    2009-01-01

    La Maison du roi constitue le corps le plus prestigieux de l’armée royale. Mais c’est aussi une troupe d’élite, redoutée sur tous les champs de bataille. Sa supériorité tactique trouve son origine dans la singularité de sa doctrine de combat. Beaucoup plus manœuvrière que les régiments ordinaires, elle s’en distingue également par sa conduite de la charge : choix de l’arme blanche, adoption d’une allure élevée et recherche du choc. Les qualités de cette troupe expliquent que Louis XIV ait vou...

  16. The under-critical reactors physics for the hybrid systems; La physique des reacteurs sous-critiques des systemes hybrides

    Schapira, J P [Institut de Physique Nucleaire, IN2P3/CNRS 91 - Orsay (France); Vergnes, J [Electricite de France, EDF, Direction des Etudes et Recherches, 75 - Paris (France); Zaetta, A [CEA/Saclay, Direction des Reacteurs Nucleaires, DRN, 91 - Gif-sur-Yvette (France); and others

    1998-03-12

    This day, organized by the SFEN, took place at Paris the 12 march 1998. Nine papers were presented. They take stock on the hybrid systems and more specifically the under-critical reactors. One of the major current preoccupation of nuclear industry is the problems of the increase of radioactive wastes produced in the plants and the destruction of the present stocks. To solve these problems a solution is the utilisation of hybrid systems: the coupling of a particle acceleration to an under-critical reactor. Historical aspects, advantages and performances of such hybrid reactors are presented in general papers. More technical papers are devoted to the spallation, the MUSE and the TARC experiments. (A.L.B.)

  17. Validité des licences de logiciel sous plastique en droit français et comparé

    Girot, C.A.

    1998-01-01

    The development of 'shrinkwrap licences' as an effective means to mass-market software has,oddly enough, generated no debate in France. Several foreign examples on the contrary tend to show that such discussion exists elsewhere in Europe and also in the United States and in Singapore. The article

  18. Évolution de la surface de plasticité sous chargement biaxial dans un acier inoxydable duplex

    Aubin, V.; Quaegebeur, P.; Degallaix, S.

    2002-12-01

    Nous proposons une méthodologie de mesure automatique de la surface de plasticité pendant des chargements cycliques biaxiaux. La surface de plasticité est mesurée de manière discrète avec un faible offset de déformation plastique (2 10^{-5}) et des paramètres de mesure optimisés. La méthode est appliquée à un acier inoxydable duplex soumis à un trajet de chargement non-proportionnel. Les résultats montrent une distorsion et une translation de la surface de plasticité sans changement de taille. La méthode présentée permet également de vérifier la normalité de la vitesse d'écoulement plastique par rapport à la surface de plasticité.

  19. Amélioration des propriétés physiques et chimiques du sol sous l ...

    SARAH

    28 févr. 2014 ... sol autour de Lubumbashi a profondément changé et la savane correspond à la dégradation de la forêt claire ... couverture, ont été apportés à des quantités différentes en fonction des traitements. Le coût d'acquisition ... sur les deux lignes du milieu et le rendement a été ajustés au taux d'humidité de 14%.

  20. Étude de la faisabilité des cycles sous-critiques et supercritiques de Rankine pour la valorisation de rejets thermiques

    Le , Van Long

    2014-01-01

    This thesis concerns the feasibility study of subcritical and supercritical organic Rankine cycles for industrial waste heat recovery at relatively low temperature. Initially, a state of the art of ORCs (Organic Rankine Cycles) and their working fluids has been achieved. We conducted a preliminary comparison of several configurations from the scientific literature. In a second step, methods of energy and exergy analysis were applied to evaluate and optimize the performance of the ORCs. Indeed...

  1. Étude de la faisabilité des cycles sous-critiques et supercritiques de Rankine pour la valorisation de rejets thermiques

    Le , Van Long

    2014-01-01

    This thesis concerns the feasibility study of subcritical and supercritical organic Rankine cycles for industrial waste heat recovery at relatively low temperature.Initially, a state of the art of ORCs (Organic Rankine Cycles) and their working fluids has been achieved. We conducted a preliminary comparison of several configurations from the scientific literature.In a second step, methods of energy and exergy analysis were applied to evaluate and optimize the performance of the ORCs. Indeed, ...

  2. SiO{sub 2} on silicon: behavior under heavy ion irradiation; SiO{sub 2} sur silicium: comportement sous irradiation avec des ions lourds

    Rotaru, C

    2004-03-15

    Heavy ion irradiation was performed on a-SiO{sub 2} layers deposited on Si. Damage of the surface was studied by means of Atomic Force Microscopy. Hillocks appear for an electronic stopping power higher than 16 keV/nm. The height of the hillocks decreases with the thickness of the oxide layer. Infrared Spectroscopy studies show that the damage threshold for a-SiO{sub 2} is at an electronic stopping power of 2 keV/nm. Therefore it is probable that the origin of the hillocks comes from the silicon layer. This could be explain within the frame of thermal spike model. The theoretical thresholds are 8 keV/nm and 1.8 keV/nm for silicon and a-SiO{sub 2} respectively. Chemical etching after irradiation gives a technical possibility to create nano-pits, whose size and shape can be controlled. Additionally, these structures allowed to determine the AFM tip radius. (author)

  3. Coldness distribution by stabilized ice slurries. Study of the behaviour under thermal cycling; Distribution du froid par coulis de glace stabilisee. Etude du comportement sous cyclage thermique

    Jacquier, D.

    2004-10-01

    The purpose of this work is to study a two-phase secondary refrigerant composed of phase-change particles suspended in a carrying liquid. This mixture has been hydraulically and thermally characterised. Moreover, some visualizations of flow patterns have been performed. Measurements of pressure losses have been realised in the case of solid state of the particles and in the case of liquid state. Heat transfer balances allowed us to show an improvement of a 1,9 factor before phase-change, in comparison with the case of a pure carrying liquid (without any particles). Flow patterns, which were theoretically specified, in function of fluid speed, have been observed experimentally. (author)

  4. A damage model of Zr {alpha} under cyclic loading at 200 degree Celsius; Modelisation de l`endommagement du Zr {alpha} sous chargement cyclique a 200 deg C

    Vogel, C.; Drubay, B. [CEA Centre d`Etudes de Saclay, 91 - Gif-sur-Yvette (France). Dept. de Mecanique et de Technologie; Cailletaud, G. [Ecole Nationale Superieure des Mines, 75 - Paris (France); Mottot, M. [CEA Centre d`Etudes de Saclay, 91 - Gif-sur-Yvette (France). Direction des Technologies Avancees

    1994-12-31

    A damage model for anticipating zirconium {alpha} test-piece rupture under cyclic solicitations at 200 degree Celsius is presented. The article is divided into three parts : an experimental approach, the damage model presentation and the application of this model. (O.L.). 10 refs., 7 figs., 4 tabs.

  5. Microstructural evolutions of zirconium alloys under irradiation. Link with the irradiation growth phenomenon; Evolutions microstructurales des alliages de zirconium sous irradiation. Liens avec le phenomene de croissance

    Simonot, C

    1995-07-18

    This study deals with the irradiation-induced growth and microstructural evolutions of Zircaloy-4 type materials (ZrSn{sub 1.2-1.7} Fe{sub 0.18-0.24} Cr{sub 0.07-0.13} O{sub 0.09-0.15}), used as cladding and guide-tubes in PWR`s fuel assemblies. The main objective was to obtain a better understanding of the growth acceleration which may occur at high doses for the recrystallized metallurgical state. The elongation values of stress-free tubes irradiated at 400 deg in experimental reactors give clear indication of accelerated growth after a critical dose. Microstructural investigations reveal some large basal plane dislocation loops with vacancy character, which is an unexpected defect configuration for an hexagonal material with a c/a ratio less than the ideal value. In addition, a significant redistribution of iron and chromium solute elements comes from the dissolution of the initial Zr(Fe,Cr){sub 2} phases. In a guide-tube irradiated to high dose at 320 deg in a power reactor, a large density of these c-component loops was also observed in coincidence with a large iron re-solution due to the progressive partial amorphization of Laves phases. By contrast, as long as a negligible amount of iron is available in the matrix (start of progressive) amorphization at 350 deg or complete amorphization without any chemical change at 280 deg, only prism plane loops with interstitial and vacancy character are observed and the steady-state growth rate is low. A mechanism taking into account the Diffusional Anisotropy Difference of the radiation induced point defects seems to be the most suitable to explain the correlations between microstructural evolutions and growth rates. However it does not allow to predict the dose necessary for the formation of the basal plane loops responsible for the growth acceleration. (Abstract Truncated)

  6. Assessment of subcriticality during PWR-type reactor refueling; Evaluation de la sous-criticite lors des operations de chargement d'un reacteur nucleaire REP

    Verdier, A

    2005-04-15

    During the core loading period of a PWR, any fuel assembly misplacements may significantly reduce the existing criticality margin. The Dampierre 4-18 event showed the present monitoring based on the variations of the outside-core detector counting rate cannot detect such misplacements. In order to circumvent that, a more detailed analysis of the available signal was done. We particularly focused on the neutronic noise analysis methods such as MSM (modified source multiplication), MSA (amplified source multiplication), Rossi-{alpha} and Feynman-{alpha} methods. The experimental part of our work was dedicated to the application of those methods to a research reactor. Finally, our results showed that those methods cannot be used with the present PWR instrumentation. Various detector positions were then studied using Monte Carlo calculations capable of following the neutron origin. Our results showed that the present technology does not allow us to use any solution based on neutron detection for monitoring core loading. (author)

  7. Massivement en grève le CERN frole le big bang le débrayage des fonctionnaires et sous-traitants cristallise la crise

    Stampfli, B

    2002-01-01

    Around 1000 staff in total, demonstrated at CERN today, to protest against radical measures proposed by CERN management. CERN needs to find around 850 million CHF to supplement the budget of the LHC project.

  8. Représentations de la déviance fiscale en France du consentement sous contrôle à la concertation citoyenne

    Péclat , Mélanie

    2015-01-01

    This dissertation is based on the results from a survey on the representations of tax deviance constructed by public opinion in France and gives a novel answer to the question of tax compliance. This research, situated at the crossroads between political science, sociology, philosophy and psychology, uses both quantitative and qualitative methods to reveal how the consideration of tax deviance representations can lead to the construction of fiscal civism. Looking first at the influence of val...

  9. L'application des normes IAS/IFRS par les entreprises françaises cotées : une décision sous influence institutionnelle

    Barbu, Elena

    2006-01-01

    International audience; Cet article cherche à démontrer le rôle des facteurs institutionnels dans l'application des normes comptables internationales par les entreprises françaises cotées. Pour cela, nous avons analysé les réponses à un questionnaire fondé sur l'approche néo-institutionnelle, envoyé en 2005 aux directeurs financiers des entreprises du CAC 40 et Euronext 100. Les résultats obtenus ont permis de mettre en évidence que la décision d'appliquer les IAS/IFRS est influencée par l'en...

  10. Les Abeilles de la sous-famille des Halictinae en Nouvelle-Guinée et dans L'archipel Bismarck (Hymenoptera: Apoidea: Halictidae)

    Pauly, A.

    1986-01-01

    During our studies of various collections of Halictinae from New-Guinea and Bismarck Archipelago, 54 species were found: 2 Sphecodes (subgenera Sphecodes and Callosphecodes), 3 Pachyhalictus, 1 Urohalictus, 3 Lasioglossum (subgenera Parasphecodes, Nesohalictus and Ctenonomia) and 45 Homalictus (5

  11. La transestérification hétérogène de l’huile de tournesol sous alumine : Production du biodiesel EEHV

    MESBAHI, Dalila

    2012-01-01

    La transestérification d’huiles végétales est une réaction catalytique homogène et hétérogène, elle est constituée par trois étapes consécutives et réversibles .Après la dernière étape on obtient un mélange d’esters : le biodiesel. L’huile de tournesol, de commerce, utilisée a été distillée. Celle –ci présente une masse volumique de 0,92 g.cm-3 et une viscosité de 54,6 mm2.s-1 à 20°C. Les analyses par UV-VIS, FTIR, CPG et HPLC ont montré que cette huile de tournesol est classique c'est-à-dire...

  12. L'arabe marocain en « sous-France » : Statuts sociolinguistique et culturel des personnes issues de l'immigration marocaine

    Abourahim Bouaissi Maha

    2014-07-01

    Full Text Available L’arabe marocain serait de moins en moins parlé dans les familles issues de l’immigration marocaine en France, et par là-même, la pratique du bilinguisme mêlant français et arabe marocain serait en péril. Afin de pouvoir confirmer ou infirmer une telle hypothèse, j’ai donc mené un travail d’enquête de terrain s’étalant sur 7 années auprès de deux familles afin de constituer mon travail de thèse. L’étude comparative de deux profils de familles distinctes était nécessaire. L’une, dans laquelle les parents avaient été scolarisés au Maroc et avaient donc emporté avec eux un minimum de bagages linguistiques leur permettant de pouvoir communiquer en français et en arabe marocain avec leurs enfants, la famille B. L’autre, dans laquelle les parents n’avaient pas été scolarisés et auraient donc été amenés à utiliser seulement l’arabe marocain au sein du foyer, la famille A. L’étude des parcours de migration, les statuts des langues en question, et les représentations linguistiques aideront donc, dans un premier temps, à mieux comprendre les comportements langagiers de chacun. Ceux-ci seront ensuite présentés et analysés afin de mettre en lumière les paramètres susceptibles d’intervenir sur la transmission de l’arabe marocain en France, seule garante de la pérennité du code switching maroco-français.

  13. Les sols de la moyenne vallée du fleuve Sénégal : caractéristiques et évolution sous irrigation

    Boivin, Pascal; Favre, F.; Maeght, J.L.

    1998-01-01

    Les sols alluviaux de la moyenne vallée du fleuve Sénégal, développés en climat aride, sont l'objet d'aménagements hydro-agricoles visant à développer les productions irriguées. Pour l'instant, la riziculture est la production principale, complétée par du maraîchage. Ces dépôts fluviaux et fluvio-marins récents sont organisés en unités géomorphologiques. Les bourrelets de berge des multiples bras du fleuve Sénégal sont des formations de texture argilo-sablo-limoneuse. Les cuvettes de décantat...

  14. Éléments de la crise de l'Empire ottoman sous Sélim III (1789-1807)

    Lemarchand, Guy

    2008-01-01

    C'est à la fin du XVIIIe siècle que s'aggrave brutalement le déclin de l'Empire ottoman, avec l'échec des réformes d'une ampleur sans précédent menées par Sélim III. Se sont dressées contre lui des forces sociales diverses, depuis les fermiers d'impôts jusqu'au petit peuple d'Istanbul, qui avaient intérêt ou croyaient avoir intérêt à ne rien changer, auxquelles se sont joints les gouverneurs cherchant à se tailler des principautés et les états étrangers voulant conquérir de nouvelles province...

  15. Installation et Configuration Centralisées et Automatisées d’une Ferme de Serveur sous SLC6

    Tourneyre, Stéphane; Mesnard, Emmanuel

    This report aims to present a study of the change of system installation and configuration of Linux servers with the distribution of Scientific Linux CERN (SLC) within the LHCb experiment at CERN. These servers are primarily used to sort the output data of various sensors detectors proton collisions. It was planned to explore a solution based software Cobbler / Puppet to replace the existing software, Quattor, to help install and configure automatically. First, these tests should be done on virtual machines and then putting these tools in real conditions with machines without hard disk, such as those in production. Currently, the use of software to allow configuration automates Puppet works and meets the expectations of the project manager, Niko Neufeld. Cobbler on, after various tests, it fails to meet our expectations fully. Therefore a thorough study should be continued or finding another software or by adapting Cobbler. For the part of the machines without hard disk, it should be done before the end of...

  16. The three-dimensional microstructure of polycrystalline materials unravelled by synchrotron light; La microstructure 3D des materiaux polycristallins vue sous la lumiere synchrotron

    Ludwig, W.; Herbig, M. [Universite de Lyon, INSA-Lyon, MATEIS, UMR 5510 CNRS, LyonTech Campus, Bat. Saint-Exupery, 25 avenue Jean Capelle, F-69621 Villeurbanne Cedex (France); Ludwig, W.; King, A; Reischig, P. [European Synchrotron Radiation Facility, 6 rue J. Horowitz, BP 220, F-38043 Grenoble (France); Marrow, J. [University of Oxford, Department of Materiels, Parks road, Oxford OX1 3PH (United Kingdom); Babout, L. [Computer Engineering Department, Technical University of Lodz, ul. Stefanowskiego 18/22, PL-90- 537 Lodz (Poland); Mejdal Lauridsen, E. [Materials Research Department, Riso National Laboratory for Sustainable Energy, Technical University of Denmark (DTU), Building 228, PO Box 49, DK-4000 Roskilde (Denmark); Proudhon, H. [MINES ParisTech, Centre des Materiaux, UMR 7633 CNRS, BP 87, F-91003 Evry Cedex (France)

    2011-07-01

    Synchrotron radiation X-ray imaging and diffraction techniques offer new possibilities for non-destructive bulk characterization of polycrystalline materials. Minute changes in electron density (different crystallographic phases, cracks, porosities) can be detected using 3D imaging modes exploiting Fresnel diffraction and the coherence properties of third generation synchrotron beams. X-ray diffraction contrast tomography, a technique based on Bragg diffraction imaging, provides access to the 3D shape, orientation and elastic strain state of the individual grains from polycrystalline sample volumes containing several hundred up to a few thousand grains. Combining both imaging modalities allows a comprehensive description of the microstructure of the material at the micrometer length scale. Repeated observations during (interrupted) mechanical tests provide unprecedented insight into crystallographic and grain microstructure related aspects of polycrystal deformation and degradation mechanisms in materials, fulfilling some conditions on grain size and deformation state. (authors)

  17. Report on the installations of cogeneration under obligation to buy; Rapport sur les installations de cogeneration sous obligation d'achat

    NONE

    2007-01-15

    Facing the problem of the climatic change and the increase of the fossil energies prices, the government policy of the cogeneration development follows many objectives. Among these objectives it is necessary of implement a new tariff of obligation to buy of the electricity from cogeneration and allow the existing installations to reaffirm their obligation to buy contract. The first part of this report defines the necessary conditions to better use the ecological and economical interest of the natural gas cogeneration and shows that these conditions are not favorable in France. The second part preconizes to modify the actual tariff device in order to maintain the existing park to 2015 in acceptable economical and ecological conditions. (A.L.B.)

  18. Detection and localisation of very high energy particles in underwater acoustic; Detection et localisation de particules de tres hautes energies en acoustique sous-marine

    Juennard, N

    2007-12-15

    The theme of this thesis is included in the Antares international project whose object is to build a neutrino telescope located in a deep water environment in the Mediterranean sea. In deep water sea, a neutrino can interact with a water molecule. The collision generates a luminous flash and an acoustic wave. The goal of this work is to study this acoustic sound wave and develop a system able to detect the corresponding wave front and to estimate the initial direction of the particle. We first focus on the acoustic sound wave. Two different models are studied, and works made recently have led to a mathematical expression of both signal and wave front. Then, several detection methods are studied, from the most classical to the more recent ones. The experimental comparison in semi-real situation leads to the choice of a detection method: the Extended stochastic matched filter. Position and direction of the neutrino are now estimated with a Gauss-Newton inspired algorithm. This estimator is based on a wave front propagation model and on the time detection information given by the telescope hydro-phones. Performances of the system are then estimated. An antenna structure is then proposed and a global simulation finalizes this thesis. In this simulation, detection and estimation are based on the results found in the previous sections. Underwater sea noise is real and the results of the simulation valid our works. (author)

  19. Etude du comportement des cultures de tomate (Lycopersicon esculentum Mill. et de piment (Capsicum annuum L. conduites en lignes simples et lignes jumelées sous serre

    Boujelben, A.

    2004-01-01

    Full Text Available Behaviour Study of Tomato Lycopercicum esculuntum Mill. and Red Pepper Capsicum annuum L. Crops under Greenhouse Conditions Conducted in Single and Twinned Rows. Tomato (Lycopercicum esculuntum Mill. and red pepper (Capsicum annuum L. crops under greenhouse conditions and drip irrigation are widely developed in Tunisia. Although, it is known that drip irrigation permitted some water savings. Other cultural techniques such as single or twinned planting rows combined with drip irrigation system could improve the water management. In this aim we have conducted an experimental trial under greenhouse adopting drip irrigation with simple and double amounts of water and single and twinned planting rows. Some agronomic traits in the occurrence the height of plants, the fruit number and yield per plant, the precocity and the water efficiency were studied. The red pepper culture with a spacing of 80 cm between lines, gave the best results in the simple row and simple amount of irrigation treatment. On the other hand, tomato, in twinned rows (90 cm among rows with double amount of water gave the best reaps in yield and more precocious. Whereas the higher water irrigation efficiency was obtained for the treatment combining the twinned planting rows and simple amount of water.

  20. Multi variable control of a switched ignition device: efficiency improvement under various constraints; Commande multivariable d`un moteur a allumage commande: Amelioration du rendement sous differentes contraintes

    Chaumerliac, V

    1995-03-09

    Spark-ignition engine control needs substantial improvement for various reasons: a non-linear and multivariable process, the strictness of anti-pollution constraints, the necessity of fuel economy, the variable running conditions, the aging, the reliability and the cost. The improvement of engine efficiency will be involved in this context and with the pollution constraints. This work develops a system approach and its philosophy is based on a suitable description of the main dynamics. A compartmentalized model of a spark-ignition engine and the dynamic of the vehicle is presented. The aim of this modeling is to have a good representativeness in transients and to describe the behavior of the outputs useful for control. The multivariable control is split in two independent systems. The first one controls the spark advance control to obtain the maximum torque. The second one controls the throttle and the electronic fuel injection device to have lower pollutant emissions. The spark advance closed loop control uses information measured with either a cylinder pressure sensor or a torque sensor. These studies have achieved to an adaptive tuning on engine bench. A new actuator, the electronic throttle control, can provide a higher degree of precision for the fuel/air ratio regulation system, particularly during fast accelerations and decelerations. An intake manifold pressure control is developed to coordinate the air and fuel flows. A delay strategy and a simple compensation of fuel supply dynamics allow to obtain good results on engine bench. Uncoupling the acceleration pedal and the throttle command is a promising way to improve engine efficiency and reduce exhaust emission during transient phases. (author) 59 refs.

  1. Le chagrin & la pitié : Chronique d’une cité française sous l’occupation allemande. Histoire et mémoire.

    Marie-Christine Kok Escalle

    2012-10-01

    Full Text Available Documentaire dans lequel la caméra est au service d’une idée, Le chagrin et la pitié de Marcel Ophüls n’est certes pas un film historique. Il peut en revanche être considéré comme film d’histoire. Il fait œuvre d’histoire orale en écrivant le récit d’une période à partir de témoignages de personnes qui l’ont vécue ; il fait œuvre d’histoire en proposant des interprétations de cette période à partir de documents d’archives qui soutiennent la lecture que les acteurs font de leur vie d’alors ; enfin sa portée est historique car il incite les Français à ne plus occulter leur mémoire collective concernant la période de l’Occupation allemande pendant la Deuxième Guerre mondiale.

  2. Les élites dans le monde arabo-musulman médiéval : l'exemple de Bagdad sous les Seldjoukides 

    Van Renterghem , Vanessa

    2001-01-01

    Ce bref article avait pour but d'exposer le programme de recherche d'une thèse naissante portant sur " Les élites bagdadiennes au temps des Seldjoukides ". Après un bref exposé du contexte bagdadien aux Ve-VIe/XIe-XIIe siècles, il est essentiellement consacré aux spécialistes de sciences religieuses, les ulémas, et à leurs pratiques de légitimation, distinction et reproduction d'un groupe (ou plutôt de plusieurs groupes) élitaire(s). L'article pose également la question du rôle des madrasas, ...

  3. Villes indiennes sous tutelle ? Une réflexion sur les échelles de gouvernance à partir des cas de Mumbai et Hyderabad

    Loraine Kennedy

    2011-11-01

    Full Text Available De manière croissante, les décideurs politiques en Inde perçoivent le rôle crucial des villes dans l’économie nationale et les politiques actuelles menées par les États régionaux reflètent cette prise de conscience. Basée sur les cas proches, sans être entièrement comparables, d’Hyderabad et de Mumbai, cette recherche montre que les gouvernements des États ont adopté des stratégies de croissance centrée sur la ville, à l’instar des tendances internationales. Cela soulève la question du rééchelonnage des instances décisionnelles et de l’essor de l’émergence politique des régions métropolitaines. Après l'examen détaillé des stratégies de développement économique et urbain adoptées à Mumbai et à Hyderabad, cet article défend l’idée que les grandes villes indiennes n’ont pas une position suffisamment solide pour revendiquer un poids politique vis-à-vis de leur gouvernement régional et ne sont pas armées pour s'engager sérieusement dans la construction d’une action collective à l’échelle métropolitaine. Il convient de souligner cette déconnexion paroxystique entre les fonctions politiques et économiques, dans la mesure où cela marque une différence de degré avec l’expérience européenne récente. La subordination politique des collectivités locales urbaines en Inde est aggravée par le caractère traditionnellement centralisateur des institutions politiques, la faiblesse relative des institutions locales de gouvernance (en termes de mandat et de ressources fiscales, l'absence de maires puissants et la quasi-inexistence de statut politique de la plupart des régions métropolitaines. En outre, échafauder un plan stratégique qui tienne compte de la croissance économique, de la justice sociale et de l’environnement est une tâche herculéenne, particulièrement dans une société plurielle. Ainsi, dans les deux villes les processus en cours sont conflictuels et empreints de contradictions, offrant un contraste saisissant avec l’image que projettent ces « visions » lisses d’une quête de développement comme un processus consensuel.There is growing recognition on the part of Indian policymakers that cities play a crucial role in the national economy, and current State (provincial policies reflect this shift. Based on two compelling, though not fully comparable, case studies of Hyderabad and Mumbai, this article argues that State governments are adopting city-centric growth strategies, following international trends. This shift raises the question of the rescaling of decision making processes as well as the emergence of metropolitan governance. Following a detailed examination of the economic and urban development strategies adopted in Mumbai and Hyderabad, the paper argues that large Indian cities are not in a sufficiently solid position to assert their political weight vis-à-vis regional government nor to seriously engage in a process of collective action at the metropolitan scale. This increasing disjunction between political and economic functions should be emphasized in the Indian context, since it marks a difference with recent European experience, at least a difference of degree if not substance. The political subordination of urban local bodies in India is exacerbated by the traditionally centralized nature of political institutions, the relative weakness of local institutions of governance (in terms of mandate and fiscal revenue, the absence of powerful mayors and the virtual nonexistence of a political entity at the metropolitan level. Furthermore, taking into account economic growth, social justice and the environment is a Herculean task, especially in a plural society. Hence, in both cities ongoing processes are contentious and contradictory, providing a stark contrast to the smooth vision statements that convey an image of the quest for “development” as a consensual process.

  4. Underwater behaviour of bitumen coated radioactive wastes: experimental validation of the Colonbo degradation model; Comportement sous eau des dechets radioactifs bitumes: validation experimentale du modele de degradation Colonbo

    Gwinner, B

    2004-03-01

    In the release scenario considered for geologic repository, water is thought to be the main aggressive agent with regards to bituminized radioactive waste (composed in general of 60 weight % of bitumen, 40% of soluble/insoluble salts and a few ppm of radionuclides). Since liquid water can diffuse in pure bitumen, leaching of bituminized waste results in the dissolution of the most soluble salts and leads to the development of a more or less concentrated saline solution-filled pore structure (called permeable layer). In consequence of the generation of a porous layer in the bituminized waste, leaching of salts and radionuclides can then take place. Research performed at the Atomic Energy Commission (CEA) aims therefore at understanding the consequences of ground-water immersion on the transport properties and radionuclides leaching of bituminized waste materials. To this end, a constitutive model (called COLONBO) which describes mathematically the leaching of bituminized waste has been developed. The COLONBO model is based on the following assumptions: 1. Water and dissolved salts migrate in the permeable layer according to Fick's first law. The diffusion of water and salts are quantified by effective diffusion coefficients which are unknown. 2. The mechanical properties of the bitumen matrix are not considered during leaching (free swelling). Up to now, the COLONBO model has been used only to model experimental water uptake and salt leach curves, leading (theoretical) estimates of the effective diffusion coefficients of water and salts in the permeable layer. The aim of this work was to validate experimentally the numerical results obtained with the COLONBO model. First, the correspondence between experimental and simulated water uptake and salt leach rates obtained on various bituminized waste materials is checked, leading estimates of the effective diffusion coefficients of water and salts in the permeable layer. Second, the evolution of the thickness and of the morphology of the permeable layer of partially leached bituminized waste samples is studied. The porosity and the pore distribution in the permeable layer are quantified according to a semi-automatic method based on the analysis of Environmental Scanning Electron Microscope images. The obtained experimental porosity profiles are compared successfully to those resulting from simulations performed with the COLONBO model. The effective diffusion coefficients of water and salts in the permeable layer of leached bituminized waste samples are then directly measured by through diffusion experiments. In the experiments, the flow of radioactive tracers (water and salts) through thin membranes of partially leached bituminized waste is followed in time. Due to the evolution of the bitumen specimen during the tests (continuous leaching), a specific method of analysis had to be developed to obtain reliable effective diffusion coefficients. The results show that the diffusion coefficients of water and salts increase with the porosity of the permeable layer, as expected from the COLONBO model. Overall, the direct characterization of the transport properties of the permeable layer and of the pore distribution in the permeable layer validate quantitatively the results obtained with the COLONBO model and the underlying hypotheses. Finally, constitutive models describing the leaching of elements from polymer matrices immersed in water have been applied to bituminized waste materials. With respect to COLONBO, these models account for the effect of mechanical properties of polymers on swelling and leach rates. (author)

  5. Fast ultrasonic visualisation under sodium. Application to the fast neutron reactors; Visualisation ultrasonore rapide sous sodium. application aux reacteurs a neutrons rapides

    Imbert, Ch

    1997-05-30

    The fast ultrasonic visualization under sodium is in the programme of research and development on the inspection inside the fast neutron reactors. This work is about the development of a such system of fast ultrasonic imaging under sodium, in order to improve the existing visualization systems. This system is based on the principle of orthogonal imaging, it uses two linear antennas with an important dephasing having 128 piezo-composite elements of central frequency equal to 1.6 MHz. (N.C.)

  6. 199 Étude de la qualité des eaux d'une retenue située sous climat ...

    Afrique Sciences

    Mots-clés : barrage Hassan II, Maroc, climat, eau, qualité, eutrophisation. Abstract ... However, the feasibility and management of these structures are ..... Figure 5 : Evolution spatio-temporelle de la température au barrage Hassan II. De S à P6 ...

  7. Wet skins tanning with chromium in dense CO{sub 2} under pressure; Tannage au chrome de peaux humides en CO{sub 2} dense sous pression

    Saldinari, L. [Tanneries Roux SA, 26 - Romans Sur Isere (France)]|[Tanneries du Puy (France)]|[Tanneries d' Annonay, 07 (France); Dutel, Ch. [Societe ATC (France); Perre, Ch. [CEA Centre de Pierrelatte (DCC/DTE/SLC), 26 (France)

    2000-07-01

    An ancestral gesture steadily improved through the centuries, the transformation of skins into leather includes several stages of which the principal one is tanning. Today, 90 % of the world's leather products are tanned with chromium. However, this stage is an environmental liability, and reducing the volume and chromium content of the waste has become a major issue. A first study on skin degreasing by dense CO{sub 2} helped sharply reduce the volume of the fatty effluents. To replace water by dense CO{sub 2} as the tanning medium was the logical next step. The present study was carried out in cooperation with three tanneries in the Rhone-Alpes-Auvergne area of France and a manufacturer of tanning materials. The difficulty of the study was the chemically opposed character of the two media involved. CO{sub 2} is a non-polar and lipophilic solvent while inorganic chromium is insoluble. The water present in the treated skin is a polar and ionic reaction medium and one of the reagents in tanning chemistry. The mixture of these two partially miscible compounds gives a pH 3 by carbonic acid formation. Tanning is based on the reactivity of collagen, the main component of the skin, with hydroxylated complexes of chromium. Collagen is a protein containing some chemical functions, amines (R-NH{sub 2}) and carboxylic (R-COOH) for example. These functions impart an amphoteric character to the compound. The WERNER theory of complex salts explains the formation of hydroxylated complexes of chromium and their fixing on the carboxylic functions of collagen by oxolation. pH is the key parameter in tanning. The success of the process demands chromium impregnation without fixing it at a pH lower than 5, and then to fix it by increasing the pH. This opened two alternatives for transferring chromium in the skin: solubilize chromium in CO{sub 2} via soluble organometallic complexes; or put the chromium salt into suspension without solubilizing it. The best results were obtained with the second option, which is better adapted to tanning chemistry. The water in the skin quickly absorbs the chromium in suspension. The process of tanning in CO{sub 2} medium was applied in a 10-liter cylindrical autoclave, equipped with an internal rotating basket similar in design to a traditional fuller. The optimum conditions are 80 bar and 37 deg C for pressure and temperature, 15 to 20 minutes impregnation time and 2 hours for basification, modified chromium sulfates as tanning agent, and ACTIPLEX CPS containing sodium bicarbonate as basification agents. The pH of the initial skin was 3, dropping to 2.5 after chromium impregnation and then rising to 5 after basification. The feasibility of chromium tanning in dense CO{sub 2} under pressure was demonstrated. The objectives were achieved: reduction of waste volume and chromium content, reduction of chromium use by better impregnation and fixing, shorter operating time, good end product quality. A patent was filed in October 1999. Pre-industrialization of the process is in the planning stage, with a 100-liter unit built to treat a whole skin. (authors)

  8. Etude du comportement sous charges laterales des ossatures de beton arme avec murs de remplissage de maconnerie, construites avant les annees 1960

    Lefebvre, Karine

    Reinforced concrete structures with unreinforced masonry infills (BMR) are considered vulnerable to earthquakes. Under seismic actions, infills could fail (causing injuries or death) and cause damages to columns. In Quebec and Canada, most of BMR structures have been constructed prior to the introduction of modern seismic design codes raising question on the contribution of the infill to the structure lateral resistance. The aim of this thesis is to improve modelling technique of BMR structures built in Quebec between 1915 and 1960. This type of structures is found in hospitals or schools buildings, which must comply with some post-earthquake functionality requirements. They could also be residential or office buildings. Actually, practicing engineers usually calculate seismic capacity of BMR structures without considering the infill's structural contribution to the lateral resistance. Yet, this contribution should not be omitted. The first part of the thesis investigates the construction techniques and material properties of the old BMR structures in the Province. The results are the material properties (concrete, reinforcing steel, brick, terra cotta tile, and mortar) and the characteristics of the assemblies (wall section, reinforcement details…). The second part of the thesis presents the results of series of parametric analyses to identify among modelling and geometric parameters, which ones are the most influent on the lateral load response (rigidity, fundamental period, normal modes). Linear and modal analyses were performed. The most influent parameters identified are: number of storeys, number of bays, bay's width, soft storey, openings, upper storeys modelized (instead of being replaced by punctual loads) and the modelization technique of infills panels (strut or shell). Nonlinear static analyses have been performed to identify the most influent parameters to be considered for evaluating the lateral resistance, the capacity (load / displacement) and the yielding sequence (beam versus columns versus infills). The identified parameters are the presence of the infills, the openings and the geometric characteristics of the models (number of storeys and number of bays). One important contribution of this work is the development of an equivalent strut model to represent the action of the infill. The model could be easily implemented in standard analysis software. A central axial hinge reproducing the nonlinear behaviour of the masonry is added to the strut element. This model is a hybridization of existing proposals (FEMA and others) with added innovations by the author. It has been validated with experimental and numerical analyses results from literature. An important conclusion of this thesis is that the contribution of infills to lateral load resisting capacities of BMR structures should be considered for structure of more than one storey. Infills can add up to 51 % to bare frame capacity. The National building code requires that the lateral resistance of existing buildings must be at least 60 % of the equivalent static seismic force (V2005). It is concluded that one storey BMR buildings have a sufficient resistance, while three-storeys structures exhibit plastic deformations for loads under 0,6* V2005.

  9. Du vivrier au vivrier marchand et à l'intégration sous-régionale : le cas de la filière arachide

    Essang , Timothée; Magrin , Géraud; Kadekoy-Tigague , David

    2003-01-01

    International audience; L'arachide, introduite pendant l'époque coloniale, est apparue lors des crises cotonnières comme une des pistes pour assurer des revenus complémentaires à ceux tirés du coton. L'étude dont l'objectif est de comprendre les conditions d'émergence de cette culture, fait ressortir que sa rentabilité en est une. Dans certaines conditions, cette rentabilité peut être supérieure à celle obtenue avec le coton. De plus, tout en assurant la sécurité alimentaire des populations, ...

  10. Ernest Beulé (1826-1874. Archéologie classique, histoire romaine et politique sous Napoléon III

    Yves Billard

    2012-02-01

    Full Text Available Dans la nuit du 3 au 4 avril 1874, vers minuit, un homme qui fut l’un des pionniers de l’archéologie française en Grèce et que la politique avait fini par séduire au point de faire de lui un éphémère ministre de l’Intérieur se suicide chez lui, à Paris. Le geste par lequel Ernest Beulé met fin à ses jours est digne de l’Antique. Souffrant depuis quelques semaines d’une douloureuse maladie au cœur, il saisit un poignard d’une panoplie qui ornait sa chambre et se l’enfonce dans la poitrine. Il ...

  11. Lixiviation du potassium sous culture de pomme de terre irriguée en sol sableux : impact des engrais azotés

    Chaouechi, Ameni

    2014-01-01

    Au Québec, la pomme de terre est cultivée sur des sols sableux favorisant les pertes par lixiviation de l’azote et du potassium. Selon le principe de réactions d’échanges cationiques, on a supposé que les doses et les sources d'azote puissent avoir un impact sur la lixiviation du potassium. Ainsi, une expérience a été menée, pendant trois années, dans un champ de pomme. Le dispositif expérimental est un bloc complet aléatoire de quatre répétitions constitué de 10 traitements qui sont un facto...

  12. Experimental and theoretical study of phase transitions under ball milling; Etude experimentale et modelisation des changements de phases sous broyage a haute energie

    Pochet, P

    1998-12-31

    The aim of this work was to determine how phase transition s under ball-milling depend on the milling conditions and to find out if one can rationalize such transitions with the theory of driven alloys. We have chosen two phase transitions: the order-disorder transition in Fe Al and the precipitation-dissolution NiGe. In the case of Fe Al we have found that the steady-state long range order parameter achieved under ball milling intensity; moreover the same degree of order is achieved starting from an ordered alloy or a disordered solid solution. On the way to fully disordered state the degree of order either decreases monotonically or goes through a short lived transient state. This behaviour is reminiscent of a first order transition while the equilibrium transition is second order. All the above features are well reproduced by a simple model of driven alloys, which was originally build for alloys under irradiation. The stationary degree of order results of two competitive atomic jump mechanisms: the forced displacements induced by the shearing of the grains, and the thermally activated jumps caused by vacancies migrations. Finally we have performed atomistic simulations with a Monte Carlo kinetic algorithm, which revealed the role of the fluctuations in the intensity of the forcing. Moreover we have shown that specific atomistic mechanisms are active in a dilute NiGe solid solution which might lead to ball milling induced precipitation in under-saturated solid solution. (author). 149 refs.

  13. Leaks detection in the amplifier boxes of underwater cables; Detection de fuites dans les boitiers amplificateurs de cables sous-marins

    Leveque, P

    1950-12-01

    The aim of this work is to detect leaks inside tight boxes which will be immersed in the bottom of the sea at a 4000 m depth. Radioactive sodium in the form of CO{sub 3}Na{sub 2} in aqueous solution is used as tracer. The method consists in placing the box inside a pressure cell filled up with the active solution and submitting the box to a pressure of 400 kg/cm{sup 2}. After washing with acetone and water, the activity of the box is measured. Any anomalous activity indicates the penetration of the active solution inside the box. (J.S.)

  14. EVOLUTION DES PARAMETRES ZOOTECHNIQUES DE LA CARPE ARGENTEE (HYPOPHTHALMICHTHYS MOLITRIX ELEVEE SOUS CLIMAT SEMI-ARIDE A LA STATION DE PISCICULTURE DEROUA, MAROC.

    Sana FARID

    2017-05-01

    Full Text Available The growth rate of Silver carp (Hypophthalmichthys molitrix artificially reproduced in the Deroua Fisheries Station (Morocco since 1990 varies according to the temperature (seasons and rearing modes (monoculture or polyculture. The condition coefficient, always greater than 1, shows that this species is well adapted to its habitat, which has offered the optimum physicochemical and biological conditions for its growth. The growth parameters (weight and length of the silver carp in monoculture monitored from January 2013 to March 2014 show values greater than those found in polyculture (silver Carp + Grass Carp + Common Carp or (silver Carp + Grass Carp with a slowing of growth in Spring 2013. Its growth rate remains clearly lower than that of the grass carp and the common carp in spite of the some improvement in the growth rate observed beyond July. This is due, on the one hand, to the lack of adequate food for the silver carp, mainly phytoplankton, which shows very low densities, due the excessive development of Chara vulgaris and Ceratophyllum submersum. These macrophytes extract the mineral elements (nitrate and phosphate necessary for phytoplankton development. Thus, we recommend that in a similar case and in a semi-arid climate, the provision of additional food to silver carp is desirable.

  15. Study of cements silicate phases hydrated under high pressure and high temperature; Etude des phases silicatees du ciment hydrate sous haute pression et haute temperature

    Meducin, F.

    2001-10-01

    This study concerns the durability of oil-well cementing. Indeed, in oil well cementing a cement slurry is pumped down the steel casing of the well up the annular space between it and the surrounding rock to support and protect the casing. The setting conditions of pressure and temperature may be very high (up to 1000 bar and 250 deg C at the bottom of the oil-well). In this research, the hydration of the main constituent of cement, synthetic tri-calcium silicate Ca{sub 3}SiO{sub 2}, often called C{sub 3}S (C = CaO; S = SiO{sub 2} and H H{sub 2}O), is studied. Calcium Silicate hydrates are prepared in high-pressure cells to complete their phase diagram (P,T) and obtain the stability conditions for each species. Indeed, the phases formed in these conditions are unknown and the study consists in the hydration of C{sub 3}S at different temperatures, pressures, and during different times to simulate the oil-well conditions. In a first step (until 120 deg C at ambient pressure) the C-S-H, a not well crystallized and non-stoichiometric phase, is synthesized: it brings adhesion and mechanical properties., Then, when pressure and temperature increase, crystallized phases appear such as jaffeite (Ca{sub 6}(Si{sub 2}O{sub 7})(OH){sub 6}) and hillebrandite (Ca{sub 2}(SiO{sub 3})(OH){sub 2}). Silicon {sup 29}Si Nuclear Magnetic Resonance (using standard sequences MAS, CPMAS) allow us to identify all the silicates hydrates formed. Indeed, {sup 29}Si NMR is a valuable tool to determine the structure of crystallized or not-well crystallized phases of cement. The characterization of the hydrated samples is completed by other techniques: X- Ray Diffraction and Scanning Electron Microscopy. The following results are found: jaffeite is the most stable phase at C/S=3. To simulate the hydration of real cement, hydration of C{sub 3}S with ground quartz and with or without super-plasticizers is done. In those cases, new phases appear: kilchoanite mainly, and xonotlite. A large amount of {alpha}-C{sub 2}SH is also produced. Compression tests are done to correlate macroscopic behavior and physico chemical properties of the products. With super-plasticizers, samples porosity is lower and the 28-day aged samples recover the Young modulus they had at the early stage of hydration. (author)

  16. Chemical stimulation techniques for geothermal wells: experiments on the three-well EGS system at Soultz-sous-Forêts, France

    Portier, Sandrine; Vuataz, François-David; Nami, Patrick; Sanjuan, Bernard; Gérard, André

    2012-01-01

    Rock matrix stimulation is a method of enhancing well production or injection within a broad range of challenging environments, varying from naturally fractured limestones to sandstones with complex mineralogy. A common and often successful stimulation option, matrix acidizing, utilizes acids that react and remove mineral phases restricting fluid flow. Reviewed is the technology of chemical treatments available for oil, gas and geothermal wells and the key elements and results of the chemical...

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

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

    1968-06-01

    The electron spin resonance (E.S.R.) spectra of gamma irradiated polar organic glasses, at 77 K, shows a single line centered at g {approx} 2, attributed to solvated electrons. The radicals produced on scavenging this species by electron acceptors, such as aromatic hydrocarbons, nitro-compounds and azines have been studied by E.S.R. In most cases, the radicals from these solutes, the spectra of which are observed after elimination by warming of the radicals from the matrices, are produced by protonation of the anions formed by scavenging of electrons at 77 K. Thus, in the case of glassy solutions of nitro-compounds, the radicals R NO{sub 2}H are formed. They are characterized by a{sub N} = 15 G (nitrobenzene) or a{sub N} = 28 G (nitro-alkane). These radicals are also generated by U.V, photolysis at room temperature of solutions of nitro-compounds in alcohols and are shown to be the precursors of nitroxide radicals R - N - R (with N - O) observed simultaneously. Gamma irradiation of solutions of pyridine and of the three diazines, in alcohol glasses at 77 K, produces the radical formed by hydrogen addition to these compounds. The value of the coupling constant of the additional proton (7-10 G) indicates that it is bound to a nitrogen in the sp{sup 2} hydridation state. One has shown, taking pyridine as an example, that the addition to a carbon gives a much greater value of the coupling constant, of the order of 50-60 G. (author) [French] Les spectres de resonance paramagnetique electronique (R.P.E.) obtenus apres irradiation gamma, a 77 K, de verres organiques polaires tels que les alcools, comportent une bande unique centree a g {approx} 2, attribuable aux electrons solvates. On etudie par R.P.E. les radicaux provenant de leur capture par des solutes ayant une affinite electronique, en particulier les hydrocarbures aromatiques, les composes nitres et les azines. En general, les radicaux provenant de ces solutes, dont on observe les spectres apres elimination specifique des radicaux de la matrice par rechauffement, resultent de la protonation des anions formes par capture des electrons a 77 K. Ainsi, dans le cas de solutions vitreuses de composes nitres, il se forme les radicaux R NO{sub 2}H caracterises par a{sub N} = 15 G (nitrobenzene) ou a{sub N} = 28 G (nitro-alcanes). On observe transitoirement ces memes radicaux par photolyse U.V. de solutions de composes nitres dans les alcools, a temperature ambiante, dans la cavite du spectrometre et l'on montre qu'ils sont les precurseurs de radicaux nitroxydes R - N - R (avec N - O) observes simultanement. Les solutions de pyridine et des trois diazines dans les alcools, irradiees a 77 K donnent les radicaux produits par addition d'hydrogene sur ces composes. Il semble que le proton supplementaire, dont la constante de couplage est de 7 a 10 G, soit lie a un azote dans l'etat d'hybridation sp{sup 2}. On montre que l'addition sur un carbone donnerait une constante de couplage beaucoup plus elevee, de l'ordre de 50 a 60 G, dans le cas de la pyridine. (auteur)

  18. Narration interactive ludique : les jeunes lecteurs se réapproprient la culture populaire sous forme de persona-fictions

    France Vachey

    2011-06-01

    Full Text Available En produisant une fiction de sa vie, l’homme évolue dans un entre-deux fantasmatique où se construit une identité narrative qui lui permet d’être présent à lui-même. Dans le cadre d’un jeu de rôle sur forum, écrire, jour après jour, la narration d’événements impliquant des personnages imaginés sur la base de récits littéraires populaires, et incarnés dans des récits de vie imaginée, sorte de persona-fiction, c’est, là aussi, se poser comme sujet en construction, vouloir donner à comprendre, à soi et aux autres, la psychologie de son personnage, avancer dans son histoire, intégrer les événements, et par là même, construire son identité.

  19. TL-dating applied to building archaeology: The case of the medieval church Notre-Dame-Sous-Terre (Mont-Saint-Michel, France)

    Blain, Sophie [IRAMAT-CRP2A-UMR 5060, CNRS-Universite de Bordeaux 3, Maison de l' Archeologie, F-33 607 Pessac (France); Luminescence Laboratory, Department of Archaeology, University of Durham, South Road, DH1 3LE Durham (United Kingdom)], E-mail: blain.sophie@gmail.com; Guibert, Pierre [IRAMAT-CRP2A-UMR 5060, CNRS-Universite de Bordeaux 3, Maison de l' Archeologie, F-33 607 Pessac (France)], E-mail: guibert@u-bordeaux3.fr; Bouvier, Armel [IRAMAT-CRP2A-UMR 5060, CNRS-Universite de Bordeaux 3, Maison de l' Archeologie, F-33 607 Pessac (France)], E-mail: bouvier_armel@yahoo.fr; Vieillevigne, Emmanuelle [IRAMAT-CRP2A-UMR 5060, CNRS-Universite de Bordeaux 3, Maison de l' Archeologie, F-33 607 Pessac (France)], E-mail: evieillevign@u-bordeaux3.fr; Bechtel, Francoise [IRAMAT-CRP2A-UMR 5060, CNRS-Universite de Bordeaux 3, Maison de l' Archeologie, F-33 607 Pessac (France); Sapin, Christian [Laboratoire Archeologie, Culture et Societe-UMR 8894, CNRS-Universite de Bourgogne, Dijon (France)], E-mail: sapin.christian@wanadoo.fr; Bayle, Maylis [Laboratoire de medievistique occidentale de Paris, UMR 8589, CNRS-Universite de Paris 1 (France)], E-mail: maylis.bayle@wanadoo.fr

    2007-10-15

    The recent application of thermoluminescence (TL) dating to young building materials is being increasingly developed for use in the field of buildings archaeology [; ; ]. Ensuring the accuracy of the dating method is of the utmost importance in order to achieve results which are pertinent enough to have archaeological significance. This paper deals with an archaeological building study of the first church built on the Mont-Saint-Michel (France) and improvements made to the TL-protocol in Bordeaux. The aim is to achieve precise dates for the material under analysis and therefore, a better understanding of the evolution of the building. For this study, 14 bricks have been sampled from eight different masonries and submitted for TL dating analysis. With the exception of one sample which appears to be non-contemporaneous to the others, the date results range from 900{+-}80 to 1020{+-}60 AD. The results were then averaged according to the two phases established by the archaeological building study. The first two stages of the primitive church both date from the 10th century.

  20. TL-dating applied to building archaeology: The case of the medieval church Notre-Dame-Sous-Terre (Mont-Saint-Michel, France)

    Blain, Sophie; Guibert, Pierre; Bouvier, Armel; Vieillevigne, Emmanuelle; Bechtel, Francoise; Sapin, Christian; Bayle, Maylis

    2007-01-01

    The recent application of thermoluminescence (TL) dating to young building materials is being increasingly developed for use in the field of buildings archaeology [; ; ]. Ensuring the accuracy of the dating method is of the utmost importance in order to achieve results which are pertinent enough to have archaeological significance. This paper deals with an archaeological building study of the first church built on the Mont-Saint-Michel (France) and improvements made to the TL-protocol in Bordeaux. The aim is to achieve precise dates for the material under analysis and therefore, a better understanding of the evolution of the building. For this study, 14 bricks have been sampled from eight different masonries and submitted for TL dating analysis. With the exception of one sample which appears to be non-contemporaneous to the others, the date results range from 900±80 to 1020±60 AD. The results were then averaged according to the two phases established by the archaeological building study. The first two stages of the primitive church both date from the 10th century

  1. CONTRIBUTION À L’ÉTUDE DES LIPIDES TISSULAIRES ET PLASMATIQUES CHEZ LE RAT WISTAR MÂLE SOUS RÉGIME HYPERGRAS

    BENSALAH, Meryem

    2012-01-01

    De nos jours, les pathologies associées aux accumulations lipidiques dans l’organisme humain, telle l’obésité, prennent une importance croissante dans les questions de santé. Ces maladies sont consécutives à des apports caloriques superieurs à la dépense énergétique aboutissant à un surplus de stockage des graisses. L’objectif principal de cette étude était d’évaluer l’impact d’un régime hyperlipidique hypercalorique administré pour une période de 8 semaines chez le rat male Wistar (que nous ...

  2. Une revue systématique des cibles de tension artérielle sous vasopresseurs chez des adultes gravement malades atteints d’hypotension

    Hylands, Mathieu; Moller, Morten Hylander; Asfar, Pierre

    2017-01-01

    pressure targets for vasopressor therapy in critically ill hypotensive adult patients. Two reviewers independently assessed trial eligibility based on titles and abstracts, and they then selected full-text reports. Outcomes, subgroups, and analyses were prespecified. We used GRADE (Grading...... of Recommendations Assessment, Development and Evaluation) to rate the overall confidence in the estimates of intervention effects. Results: Of 8001 citations, we retrieved 57 full-text articles and ultimately included two randomized-controlled trials (894 patients). Higher blood pressure targets were not associated...

  3. Electrical conductivity of air under the action of a shock wave; Conductivite electrique de l'air sous l'action d'une onde de choc

    Thouvenin, Jacques [Commissariat a l' energie atomique et aux energies alternatives - CEA (France)

    1960-07-01

    A method is described for the measurement of the electrical conductivity of a shock wave in air. The results reveal the preponderant part played by the NO molecule. Reprint of a paper published in Comptes rendus des seances de l'Academie des Sciences, t. 250, p. 302-304, sitting of 11 January 1960 [French] On decrit un procede de mesure de la conductivite electrique d'une onde de choc dans l'air. Les resultats font apparaitre le role preponderant joue par la molecule NO. Reproduction d'un article publie dans les Comptes rendus des seances de l'Academie des Sciences, t. 250, p. 302-304, seance du 11 janvier 1960.

  4. Stress field determination in an alloy 600 stress corrosion crack specimen; Determination du champ de contraintes dans une eprouvette de corrosion sous contrainte de l`alliage 600

    Rassineux, B.; Labbe, T.

    1995-05-01

    In the context of EDF studies on stress corrosion cracking rates in the Alloy 600 steam generators tubes, we studied the influence of strain hardened surface layers on the different stages of cracking for a tensile smooth specimen (TLT). The stress field was notably assessed to try and explain the slow/rapid-propagation change observed beyond the strain hardened layers. The main difficulty is to simulate in a finite element model the inner and outer surfaces of these strain hardened layers, produced by the final manufacturing stages of SG tubes which have not been heat treated. In the model, the strain hardening is introduced by simulating a multi-layer material. Residual stresses are simulated by an equivalent fictitious thermomechanical calculation, realigned with respect to X-ray measurements. The strain hardening introduction method was validated by an analytical calculation giving identical results. Stress field evolution induced by specimen tensile loading were studied using an elastoplastic 2D finite element calculations performed with the Aster Code. The stress profile obtained after load at 660 MPa shows no stress discontinuity at the boundary between the strain hardened layer and the rest of the tube. So we propose that a complementary calculation be performed, taking into account the multi-cracked state of the strain hardened zones by means of a damage variable. In fact, this state could induce stress redistribution in the un-cracked area, which would perhaps provide an explanation of the crack-ground rate change beyond the strain hardened zone. The calculations also evidence the harmful effects of plastic strains on a strain hardened layer due to the initial state of the tube (not heat-treated), to grit blasting or to shot peening. The initial compressive stress condition of this surface layer becomes, after plastic strain, a tensile stress condition. These results are confirmed by laboratory test. (author). 10 refs., 18 figs., 9 tabs., 2 appends.

  5. Un populisme de la misère : Haïti sous la présidence Aristide (1990-2004

    Laurent Jalabert

    2005-09-01

    Full Text Available Elu en 1990 à l’issue d’un grand mouvement populaire en sa faveur en déclarant vouloir faire passer son pays de la « misère indigne à la pauvreté digne », Jean-Bertrand Aristide a quitté son pays en 2004, 3 ans après une réélection contestée, laissant Haïti dans une situation économique et sociale dégradée. Son exercice du pouvoir s’assimile à un « populisme moderne » qui s’est constitué lentement dans le contexte d’une transition démocratique incertaine. Populiste moderne, il utilise tous les moyens pour rester au pouvoir : corruption, milices de jeunes fanatisés, diabolisation des Etats occidentaux, exhortation du peuple… Il a aussi fait appel aux méthodes habituelles du leader populiste : encadrement de la société par la terreur, les médias, le parti, la fraude électorale, la corruption…. Son échec provient des limites de ses soutiens (milices armées incontrôlables, poids et rôle incertains des mafias de la drogue, division interne à son parti, faiblesse de la police, absence d’armée, isolement international. Dans ce contexte, malgré la terreur imposée aux intellectuels et à l’opposition, il n’a pas su empêcher la montée en puissance des mécontentements. Le peuple, manipulé, n’a plus cru en son Président dès les années 2002-2003. Porté par les masses des bidonvilles au pouvoir, Aristide n’a pas répondu à leur attente. Il s’est mis dans la peau d’un populiste sans imagination. Il a échoué dans tous les domaines, sombrant dans une démagogie et un discours sans prise sur l’opinion. Le régime d’Aristide ne fut qu’un populisme de misère, indigne, pour un peuple digne toujours en quête de démocratie.Jean-Bertrand Aristide había sido elegido presidente en 1990 merced a un gran movimiento popular a su favor, cuando declaraba querer llevar a su país « de la miseria indigna a la pobreza digna ». En el 2004, 3 años después de una reelección polémica, abandonó Haití, dejando al país en una situación económica y social degradada. Su ejercicio del poder se asemeja a un « populismo moderno » edificado paulatinamente, en un contexto de transición democrática incierta. Este populista moderno utilizó todos los medios para permanecer en el poder : corrupción, milicias de jóvenes fanáticos, satanización de los Estados occidentales, exhortación del pueblo… También recurrió a los métodos tradicionales del líder populista, tales como el control de la sociedad por medio del terror, los medios de comunicación y el partido, el fraude electoral, la corrupción. Su fracaso se origina en las limitaciones de sus apoyos (milicias fuera de control, peso y papel ambiguos de las redes de narcotráfico, divisiones en su partido, debilidad de la policía, ausencia de ejército, aislamiento internacional. En este contexto, a pesar del terror impuesto a intelectuales y opositores, no pudo impedir el crecimiento del descontento. El pueblo, un tiempo manipulado, ya no creía en su Presidente en los años 2002-2003. Llevado al poder por las masas paupérrimas de los suburbios, Aristide no dio respuesta a sus expectativas. Se convirtió en un populista sin ideas. Fracasó en todos los ámbitos, cayendo en una demagogia y un discurso que no convencía a la opinión pública. El régimen de Aristide no fue más que un populismo de miseria, indigno, sufrido por un pueblo digno, siempre en busca de democracia.Jean-Bertrand Aristide was elected in 1990 resulting from a great popular movement in his favour in which he stated he wanted to transform his country from unworthy « misery to worthy poverty ». He left his country in 2004, 3 years after a disputed re-election, leaving Haiti in a deteriorated economic and social situation. His way of governing is assimilated to a « modern populism » which was slowly set up in the context of a dubious democratic transition. Modern populist, he uses all means to remain in power: corruption, militia of fanatical young people, demonisation of the Western countries, exhortation of the people… He also called upon the usual methods of populist leader: ruling the society by terror, the media, the party, electoral fraud, and corruption…. His failure is caused by the limits of his support (uncontrollable armed militia, uncertain role and weights of the drug Mafia, internal division in his own party, weakness of the police force, absence of army, international isolation. In this context, in spite of the terror imposed on intellectuals and opposition, he did not manage to prevent powerful dissatisfactions to rise. The people, manipulated, did no longer believe in their President as of the years 2002-2003. Brought to power by the populations of the shantytowns, Aristide fell short on their expectations. He had put himself in the shoes of a populist without imagination. He had failed in all fields, sinking into demagoguery and speeches without effect on the opinion. The regime of Aristide was only populism of unworthy misery for a worthy nation still seeking for democracy.

  6. Contribution { l’étude et { la cartographie des zones sensibles { l’érosion hydrique du sous bassin versant de Oued Saida

    REMMAS, HICHEME

    2014-01-01

    الح ضٌ المائ ل اٌدي سع ذٍج ى جسء من الح ضٌ المائ للمقطع، رٌم سٍ تمناخ شثو جاف، امطار غ رٍ منرظمح على مذار السنح مع جً دٌ ضغ طٌاخ انسان حٍ حً اٌٍن حٍ ف نفس ال قٌد ) قطع الاشجار الغات حٍ، الر سٌع العمران اًلرع المكثف مسثثرا للانجراف الشذ ذٌ للررتح، فًقا لل كٌالح ال طٌن حٍ للم اٌرد المائ حٍ قٌذر كم حٍ الر اًسة الناذجح عن انجراف الررتح ب 22766 طن/سنح مساىمح تذالك ف نقص نسثح الم اٍه ف سذ سًٌرخ. اجر نٌا ىذه الذراسح تاسرخذام نضام المعل مٌاخ الجغراف حٍ اًلر سمحد لنا تاسرخراج خر طٌح اصطناع...

  7. Les nouvelles théories de la criminalité en Espagne sous la Restauración (1875-1910

    Ricardo Campos

    2005-01-01

    Full Text Available Perceptible dès les années 1880, l’intérêt pour l’anthropologie criminelle est en Espagne au centre des préoccupations scientifiques et littéraires, de l’opinion publique même jusqu’au début des années 1910. Ce phénomène est intimement lié à la fascination que la criminalité et le criminel suscitent dans la société espagnole de la Restauración. Dès la fin des années 1870, la presse “commence à faire des actes criminels un usage spectaculaire, reléguant à l’arrière plan, dans les cas les plus ...

  8. Criminalité, police et gouvernement : trajectoires post-communistes, Sous la direction de Gilles Favarel-Garrigues, Paris, l’Harmattan, collection logiques politiques, 2003, 304 pages.

    Anne Wuilleumier

    2004-11-01

    Full Text Available Voici un ouvrage singulier ne serait-ce que de par la pluralité de lectures qu’il autorise ! Issues d’un colloque organisé par Gilles Favarel-Garrigues au CERI en mars 2002 sur le thème du traitement des questions de sécurité dans les pays de « l’Europe post-communiste », les huit contributions présentées ici peuvent nourrir le cas échéant une réflexion de type area studies (y compris s’agissant de discuter de la pertinence de la terminologie et de la délimitation zonale aussi bien que de « ...

  9. Search for time reversal violation in neutron decay; Recherche d'une violation de l'invariance sous le renversement du temps dans la desintegration du neutron

    Gorel, P

    2006-06-15

    The topic of this thesis is the implementation of an experimental setup designed to measure the R- and N-parameters in polarized neutron decay, together with the data analysis. Four observables are necessary for this measurement: the neutron polarization, the electron momentum and both transverse components of the electron polarization. These last two are measured using a Mott polarimeter. The other observables are determined using the same detectors. The precision to be reached on the R-parameter is 0.5%. A non zero value would sign a time reversal invariance violation and therefore would be a hint of physics beyond the Standard Model. This document presents the work done to prepare and optimize the experimental setup before the data acquisition run performed in 2004. Particular care was taken on the scintillator walls, used to trigger the acquisition and measure the electron energy. The second part concerns the implementation of methods to extract R and N from the data, and the study of the background recorded simultaneously. (author)

  10. Large Hadron Collider au CERN: des big bangs en série sous le contrôle de WorldFIP

    2007-01-01

    Thanks to WorlsFIP, associated with a GPS system, CERN is able to synchronize most of the LHC equipments, to drive the magnetic field of giant experiments, to put back automatically the clock at the hour and date events with a precision better than 10 mu s. (1 page)

  11. Report on the installations of cogeneration under obligation to buy; Rapport sur les installations de cogeneration sous obligation d'achat

    NONE

    2007-01-15

    Facing the problem of the climatic change and the increase of the fossil energies prices, the government policy of the cogeneration development follows many objectives. Among these objectives it is necessary of implement a new tariff of obligation to buy of the electricity from cogeneration and allow the existing installations to reaffirm their obligation to buy contract. The first part of this report defines the necessary conditions to better use the ecological and economical interest of the natural gas cogeneration and shows that these conditions are not favorable in France. The second part preconizes to modify the actual tariff device in order to maintain the existing park to 2015 in acceptable economical and ecological conditions. (A.L.B.)

  12. Amélioration des performances du traitement des interférences dans le domaine fréquentiel pour les communications acoustiques sous marines

    YOUCEF , Abdelhakim

    2013-01-01

    Underwater acoustic (UWA) communications allow wireless transmission between the surface and the bottom of a subsea environment based on acoustic waves. The wireless acoustic link reduces the physical infrastructure cost compared to the cable-based underwater communications. However, underwater acoustic channel imposes severe degradations on the transmitted signal. Its propagation characteristics are widely different from those of the radio channel. The multipath propagation caused by multipl...

  13. Study of silica coatings degradation under laser irradiation and in controlled environment; Etude de la degradation de couches minces de silice sous flux laser et en environnement controle

    Becker, S

    2006-11-15

    Performances of optical components submitted to high laser intensities are usually determined by their laser-induced damage threshold. This value represents the highest density of energy (fluence) sustainable by the component before its damage. When submitted to laser fluences far below this threshold, optical performances may also decrease with time. The degradation processes depend on laser characteristics, optical materials, and environment around the component. Silica being the most used material in optics, the aim of this study was to describe and analyse the physical-chemical mechanisms responsible for laser-induced degradation of silica coatings in controlled environment. Experimental results show that degradation is due to the growth of a carbon deposit in the irradiated zone. From these results, a phenomenological model has been proposed and validated with numerical simulations. Then, several technological solutions have been tested in order to reduce the laser-induced contamination of silica coatings. (author)

  14. Commande de systèmes linéaires sous contraintes fréquentielles et temporelles – Application au lanceur flexible

    Chambon , Emmanuel

    2016-01-01

    In modern control design problems, both frequency- and time-domain requirements are usually considered such that the resulting control law satisfies the specifications. Novel non-smooth optimisation techniques can be used to achieve multiple frequency-domain specifications over a family of linear models. Examples of applications include robust control design where multiple critical models for different values of the uncertain parameters are considered. This is illustrated in this thesis manus...

  15. Radiation enhanced thermal diffusion of chlorine in uranium dioxide; Diffusion thermique et sous irradiation du chlore dans le dioxyde d'uranium

    Pipon, Yves [Ecole doctorale de physique et d' astrophysique, Universite Claude Bernard Lyon-I, Lyon (France)

    2006-12-15

    This work concerns the study of the thermal and radiation enhanced diffusion of {sup 36}Cl in uranium dioxide. It is a contribution to PRECCI programme (research programme on the long-term behaviour of the spent nuclear fuel). {sup 36}Cl is a long lived volatile activation product (T = 300 000 years) able to contribute significantly to the instant release fraction in geological disposal conditions. We simulated the presence of {sup 36}Cl by implanting a quantity of {sup 37}Cl comparable to the impurity content of chlorine in UO{sub 2}. In order to evaluate the diffusion properties of chlorine in the fuel and in particular to assess the influence of the irradiation defects, we performed two kinds of experiments: - the influence of the temperature was studied by carrying out thermal annealings in the temperature range 900 - 1300 deg. C; we showed that implanted chlorine was mobile from temperatures as low as 1000 deg. C and determined a thermal diffusion coefficient D{sub 1000} {sub deg.} {sub C} around 10{sup -16} cm{sup 2}s{sup -1} and deduced an activation energy of 4.3 eV. This value is one of lowest compared to that of volatile fission products such as iodine or the xenon. These parameters reflect the very mobile behaviour of chlorine; - the irradiation effects induced by fission products were studied by irradiating the samples with {sup 127}I (energy of 63.5 MeV). We showed that the implanted chlorine diffusion in the temperature range 30 - 250 deg. C is not purely athermal. In these conditions, the diffusion coefficient D{sub 250} {sub deg.} {sub C} for the implanted chlorine is around 10{sup -14} cm{sup 2}s{sup -1} and the activation energy is calculated to be 0.1 eV. Moreover, at 250 deg. C, we observed an important transport of the pristine chlorine from the bulk towards the surface. This chlorine comes from a zone where the defects are mainly produced by the nuclear energy loss process at the end of iodine range. We showed the importance of the implantation and irradiation defects as preferential paths for a fast chlorine transport. We carried out ab initio calculations showing that chlorine is preferentially located in a substitutional site. This is in favour of a Frank-Turnbull diffusion mechanism or a vacancy/chlorine pair diffusion mechanism. Our results allowed us to make following considerations concerning the repartition of {sup 36}Cl in the spent fuel after three years operation of a PWR. Considering the same mean value around 3.10{sup -14} cm{sup 2}.s{sup -1} obtained for the diffusion coefficients at 1200 deg. C and the irradiation induced diffusion coefficient at 250 deg. C, the diffusion length L, expressed as L=(Dt){sup 1/2}, will reach 17 {mu}m after 3 years. Considering a mean grain size around 18 {mu}m, it results that there is a great probability for {sup 36}Cl to have reached the grain boundaries after 3 years, Moreover, due to the thermal gradient between the core of the fuel rod and its periphery, most of the {sup 36}Cl will probably have moved to the rim and even to the gap. This chlorine would then be almost entirely available for the instant release fraction. (author)

  16. Le modèle judiciaire libéral mis à l’épreuve : la surveillance des juges sous le Directoire

    Berger, Emmanuel

    2007-01-01

    La justice du Directoire est principalement identifiée aux différentes violations infligées par le gouvernement afin de contrôler le pouvoir judiciaire et durcir la répression criminelle. Cette représentation est, en réalité, partiale. L’auteur tente de le prouver à travers l’analyse d’un aspect essentiel du système judiciaire directorial : la surveillance des juges. L’étude des normes et des pratiques montre que le mode de surveillance établi par le code des délits et des peines respecte la ...

  17. Strongly correlated electrons at high pressure: an approach by inelastic X-Ray scattering; Electrons correles sous haute pression: une approche par diffusion inelastique des rayons X

    Rueff, J.P

    2007-06-15

    Inelastic X-ray scattering (IXS) and associated methods has turn out to be a powerful alternative for high-pressure physics. It is an all-photon technique fully compatible with high-pressure environments and applicable to a vast range of materials. Standard focalization of X-ray in the range of 100 microns is typical of the sample size in the pressure cell. Our main aim is to provide an overview of experimental results obtained by IXS under high pressure in 2 classes of materials which have been at the origin of the renewal of condensed matter physics: strongly correlated transition metal oxides and rare-earth compounds. Under pressure, d and f-electron materials show behaviors far more complex that what would be expected from a simplistic band picture of electron delocalization. These spectroscopic studies have revealed unusual phenomena in the electronic degrees of freedom, brought up by the increased density, the changes in the charge-carrier concentration, the over-lapping between orbitals, and hybridization under high pressure conditions. Particularly we discuss about pressure induced magnetic collapse and metal-insulator transitions in 3d compounds and valence fluctuations phenomena in 4f and 5f compounds. Thanks to its superior penetration depth, chemical selectivity and resonant enhancement, resonant inelastic X-ray scattering has appeared extremely well suited to high pressure physics in strongly correlated materials. (A.C.)

  18. Evolution des acides aminés libres dans le moût de raisin sous l'action des levures de fleur

    M.C. POLO

    1974-03-01

    La plus grande partie des travaux qui existent dans la bibliographie sur la teneur en acides aminés du raisin pendant l'évolution de la maturation ainsi que sur les teneurs des moûts et des vins de différents pays, ont été réalisés par chromatographie sur papier ou en utilisant des méthodes microbiologiques ou colorimétriques.

  19. Quadrillages labyrinthiques: l’échiquier Caillois. Centenaire de la naissance de Roger Caillois, sous la direction de Valeria Emi Sgueglia et André-Alain Morello

    Gardini, Michela

    2016-01-01

    Il volume si presenta come un omaggio per il centenario della nascita di Roger Caillois (1913) e raccoglie saggi di autori diversi in onore del celebre critico. Come suggerito dal titolo, l’opera di Caillois a cui tutti gli autori fanno riferimento è Cases d’un échiquier del 1970, un’opera mosaico presa come simbolo della molteplicità della ricerca epistemologica di Caillois. In apertura, dopo l’articolo introduttivo di André-Alain Morello (Une des récompenses de la rêverie, pp. 9-13), Enzo ...

  20. Heat exchanges in nitrogen and hydrogen boiling under pressure; Echanges thermiques dans l'azote et l'hydrogene bouillant sous pression

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

    1961-07-01

    The heat transfer between a horizontal wall and boiling nitrogen or hydrogen has been studied from atmospheric pressure to 2/3 of the critical pressure. The q = f(T) curves are rather well defined for nitrogen but more uncertain for hydrogen. In general, the measured {delta}T are inferior to those given by various authors using the wire method. The q{sub max} = f(P) more reproducible curves show for both fluids a maximum at about 0.4 P{sub cr} say 45 watt cm{sup -2} for 12.5 atm in nitrogen and 16 watt cm{sup -2} for 5.5 atm in hydrogen. Beyond, calefaction appears with a reduced dissipated power, rough reduction (90 per cent in few degrees) for nitrogen, smoother for hydrogen. (author) [French] On a etudie l'echange de chaleur entre une paroi horizontale et l'azote ou l'hydrogene bouillant depuis la pression atmospherique jusqu'au 2/3 de la pression critique. Les courbes q = f(T) sont assez bien definies pour l'azote mais accusent une marge d'incertitude pour l'hydrogene. En generale, les {delta}T mesurees sont inferieures a celles obtenues par divers auteurs utilisant la methode du fil. Les courbes plus reproductibles de q{sub max} f(P) passent par un maximum pour les deux liquides a environ 0,4 P{sub cr}, c'est-a-dire 45 watt cm{sup -2} pour 12,5 atm dans l'azote et 16 watt cm{sup -2} pour 5,5 atm dans l'hydrogene. Au-dela, la calefaction se produit avec un pouvoir dissipatif reduit, une reduction brusque pour l'azote (90 p. 100 en quelques degres) et plus reguliere pour l'hydrogene. (auteur)

  1. Anna Lampérière, solidarité et citoyenneté féminine sous la Troisième République

    Anne R. Epstein

    2008-12-01

    Full Text Available Cet article examine les idées de l’institutrice Anna Lampérière, l’une des rares femmes à avoir contribué à la discussion théorique sur l’idéologie de la solidarité pendant la Troisième République. Vue dans le contexte de son parcours personnel et de son engagement civique, la pensée d’A. Lampérière offre un aperçu inédit d’un modèle solidariste de citoyenneté féminine sans droit de vote. Au sein d’une culture d’associations florissante au début du XXe siècle, elle participe à la création et au fonctionnement d’importantes associations mixtes qui, par l’éducation civique, visent la mise en place de l’idéologie solidariste de Léon Bourgeois. Se proclamant anti-féministe, Anna Lampérière se présente néanmoins comme une défenseuse de la cause des femmes et du progrès social et, comme beaucoup de ses contemporains, elle place la réforme scolaire au cœur de son projet républicain. Après une analyse de la vision sociale d’Anna Lampérière, l’article examine les pratiques civiques et la structure mixte selon les sexes de la Société pour l’éducation sociale, une association pour la promotion du solidarisme, dont elle a été Secrétaire générale. L’idéologie solidariste et sa pratique avaient un attrait pour des femmes républicaines comme Anna Lampérière qui avaient une vocation civique mais qui n’étaient pas attirées par un modèle égalitaire de la citoyenneté.Anna Lampérière, solidarité and female citizenship in the Third Republic This article explores the ideas of educator Anna Lampérière, one of the rare women to contribute significantly to the theoretical discussion about the ideology of solidarity during the Third Republic. Viewed in tandem with her own personal history and civic activism, Lampérière’s thought provides unique insight into a possible solidarist model of female citizenship without voting rights. Operating within the flourishing associational culture of the early twentieth century Anna Lampérière helped initiate and run important gender-inclusive civic education projects as a way of putting into practice Léon Bourgeois’s solidarist ideology. A self-identified antifeminist, she nonetheless saw herself as an advocate for women and promoter of social progress and, like many contemporaries, placed education reform at the center of her republican project. Following a discussion of Anna Lampérière’s social vision, the article the examines the gender-inclusive civic practices and structure of the Société pour l’éducation sociale, an association for the promotion of solidarism of which she served as Secretary General. Solidarist ideology and practice held appeal for republican women like A. Lampérière who felt a civic vocation but were put off by egalitarian models of citizenship.

  2. Le mal de pott sous occipital révélé par un abcès rétro pharyngien a ...

    Introduction : Pott's disease is the most frequent localisation of osteo-articular tuberculosis. The suboccipital localisation remains rare. Case report : A 12-years old boy, admitted for cervicalgy and dysphagia. His clinical exam revealed a swelling of posterior pharyngeal wall associated with a basicervical tumefaction ...

  3. Modalities of vegetation management beneath and in the vicinity of overhead power lines; Modalites de gestion de la vegetation sous et aux abords des lignes electriques

    NONE

    2000-07-01

    This guidebook was elaborated in coordination with the French professional national center of forestry property (CNPPF), Electricite de France (EDF), the national federation of contractors of rural agricultural and forestry works (FNETARF), the national federation of the syndicates of sylviculture forestry owners (FNSPFS), the institute for forest development (IDF), the national forest office (ONF), the French manager of the power grid (RTE) and some local agriculture organizations. Its goal is to supply concrete answers to the questions concerning the management of vegetation in the direct vicinity of overhead power lines, and in particular the rights and obligations of land owners with respect to the maintenance of vegetation. This guidebook represents a first step towards the improvement of today's practices in this domain: legal and technical questions and answers, glossary, regulatory texts, useful addresses and bibliography. (J.S.)

  4. Pouvoirs locaux et organisation du territoire des cités pinéniciennes sous l'Empire perse achéménide

    Josette Elayi

    1997-01-01

    Full Text Available Este articula trata de las ciudades fenicias y de la organizaciôn de sus territorios durante el Edad del Hierro lll/Perfodo Persa (del s. vi al s. iv a.C. Una descripciôn geogrâfica de las ciudades-estados fenicias es propuesta segûn la documentaciàn conocida actualmente. Las estructuras social-politicas de estas ciudades son estudiadas y caracterizadas en comparaciôn con los otros estados del Prôximo Oriente y con las ciudades griegas contemporâneas (poleis. Se trata también de la situaciôn de las ciudades fenicias en el cuadro politico del imperio perso, en particular de las relaciones entre el gobierno central y los gobiernos locales autónomos.This paper deals witfi the Ptioenician local powers and the organization of tfieir territories during the Iran Age lll/Persian Period (vith-ivth B.C.. A geograpfiical description of the Phoenician city-states is proposed from the présent state of documentation. The socio-political structures of thèse cities are studied and characterized in comparison with the neighbouring Near Eastern states and the contemporaneous Greek cities (poleis. The place of the Phoenician cities in the political framework of the Persian empire is aiso analysed, in particular the relations between the central power and the local autonomous powers.

  5. La multiplication végétative du goyavier Psidium guayava L. sous climat soudano sahélien du nord Cameroun

    Hamasselbé, A.

    2005-01-01

    Vegetative Propagation of Guyava Psidium L. Guavaya under Sudano Sahelian Climate in the North Cameroon. Goyava (Psidium guajava L.) is a fruit tree, which is well suited to the climate of north Cameroon. After three years of mass selection at Kismatari fruit tree research station, release into farmers' fields of the high yielding selected plant material was not possible due to lake of multiplication techniques adapted to the agro-climatic conditions of this fruit tree station. Preliminary re...

  6. La multiplication végétative du goyavier Psidium guayava L. sous climat soudano sahélien du nord Cameroun

    Hamasselbé, A.

    2005-01-01

    Full Text Available Vegetative Propagation of Guyava Psidium L. Guavaya under Sudano Sahelian Climate in the North Cameroon. Goyava (Psidium guajava L. is a fruit tree, which is well suited to the climate of north Cameroon. After three years of mass selection at Kismatari fruit tree research station, release into farmers' fields of the high yielding selected plant material was not possible due to lake of multiplication techniques adapted to the agro-climatic conditions of this fruit tree station. Preliminary results of vegetative propagation trials showed that grafting and aerial layering are not practicable at Kismatari station. Terrestrial layering is the most adapted multiplication technique for a massive production of homogeneous plant material to meet research and farmers' needs.

  7. Lifetime prediction of structures submitted to thermal fatigue loadings; Prediction de duree de vie de structures sous chargement de fatigue thermique

    Amiable, S

    2006-01-15

    The aim of this work is to predict the lifetime of structures submitted to thermal fatigue loadings. This work lies within the studies undertaken by the CEA on the thermal fatigue problems from the french reactor of Civaux. In particular we study the SPLASH test: a specimen is heated continuously and cyclically cooled down by a water spray. This loading generates important temperature gradients in space and time and leads to the initiation and the propagation of a crack network. We propose a new thermo-mechanical model to simulate the SPLASH experiment and we propose a new fatigue criterion to predict the lifetime of the SPLASH specimen. We propose and compare several numerical models with various complexity to estimate the mechanical response of the SPLASH specimen. The practical implications of this work are the reevaluation of the hypothesis used in the French code RCC, which are used to simulate thermal shock and to interpret the results in terms of fatigue. This work leads to new perspectives on the mechanical interpretation of the fatigue criterion. (author)

  8. Characteristics definition and optimisation of an integrated electromechanical battery under cyclic loading; Caracterisation et optimisation d'une batterie electromecanique sous chargement cyclique

    Kerzreho, C.

    2002-01-15

    This work takes place into a multidisciplinary project, gathering mechanical and electromechanical specialists, with the aim to design a 3 kWh household electromechanical battery module. The energy is stored as kinetic one in a flywheel. The main characteristics of this battery are a high yield, a long life duration and a minimal discharge time over one hour. At a low cost, it could be used in conjunction with alternative electric sources and to secure and regulate home current supplies and consumption. Following a literature review of the available technologies, the flywheel similitude properties are demonstrated and capabilities design coefficients are defined taking into account the stress cycles. In order to define criterions to choose the flywheel material and geometry, the results are applied to the major literatures configurations including metals, composites or ceramics. They are brought together as graphical maps and, using optimal solution surfaces, they show the compromises between the design criterions such as specific energy, energy density, maximal rotational velocity and cost. A single suited structure is then defined which integrates into the flywheel some parts of the motor-generator and of the magnetic bearings. A global design process is conducted taking into account the specific properties and the interactions between the components. The geometry of the motor-generator rotor is optimised then, improving the battery performances. The feasibility of an auto-fitting process is proposed showing that endurance limit depends on flywheel slenderness. The build prototype is finally presented. (author)

  9. Hydrates plugs dissociation in pipelines; Dissociation des bouchons d'hydrates de gaz dans les conduites petrolieres sous-marines

    Nguyen Hong, D.

    2005-03-15

    Natural gas hydrates plugs cause problems during drilling, well operations, production, transportation and processing of oil and gas. Especially, it is a very serious problem in off-shore oil transportation where low temperature and high pressure become more and more favourable to gas hydrate formation as the new production wells are more and more deeper. Up to now, although many studies have been developed concerning the possibility of preventing pipe plugging, there is limited information in open literature on hydrate plugs dissociation and all models in literature are numerically complicated. In this study, hydrate plugs are formed from water in n-dodecane mixture with addition of a dispersant E102B in two different experimental apparatus in order to obtain hydrates plugs with different sizes (diameter of 7, 10.75 and 12 cm). Then, the plugs are dissociated by the method of two-sided depressurization. In this paper, we propose a numerical model which describes the dissociation of gas hydrate plugs in pipelines. The numerical model, which is constructed for cylindrical coordinates and for two-sided pressurization, is based on enthalpy method. We present also an approximate analytical model which has an average error 2.7 % in comparison with the numerical model. The excellent agreement between our experimental results, literature data and the two models shows that the models give a good prediction independently of the pipeline diameter, plug porosity and gas. The simplicity of the analytical model will make it easier in industrial applications. (author)

  10. Le NOTCH, principal régulateur du sous-type et de l'hétérogénéité ...

    un des principaux obstacles à un traitement efficace. En effet, l'hétérogénéité est causée par des mutations et d'autres processus qui entraînent différentes fonctions et différents phénotypes des cellules cancéreuses. Il est essentiel de ...

  11. Pouvoir et religion à la chapelle royale de Versailles sous Louis XIV Power and religion at the royal chapel of Versailles under Louis XIV

    Alexandre Maral

    2007-12-01

    Full Text Available D’une manière peut‑être plus sensible que partout ailleurs, les objets et les insignes du pouvoir prennent une importance particulière dans le contexte du cérémonial liturgique de la religion catholique. À la chapelle royale de Versailles, la présence régulière du monarque et de sa cour complique encore la situation, d’autant que la desserte est assurée par deux corps distincts d’ecclésiastiques. Dépassant le simple cadre des préséances, Louis XIV a défini autour de sa personne royale un système rituel susceptible d’en manifester le caractère épiscopal dérivé du sacre. De même, l’enjeu juridictionnel représenté par la Chapelle royale se traduit par un jeu subtil d’attitudes, de gestes et de rites, chorégraphie sacrée qui accompagne et exprime les revendications des partisans et des adversaires de l’exemption du lieu de culte royal au regard du diocèse de Paris. Ce discours trouve un écho partiel dans le programme décoratif de la chapelle définitive du palais, achevée en 1710.Objects and symbols of power take on a particular importance in the liturgical ceremony of the Catholic Church, perhaps more so than in any other context. At the royal chapel of Versailles, the regular presence of the king and his court complicated the situation further, all the more so in that religious ceremony was administered by two distinct ecclesiastic bodies. Beyond the rules of precedence, Louis XIV had introduced around his royal persona a system of ritual that would manifest the episcopal identity conferred upon him by his coronation. Similarly, the jurisdictional authority represented by the royal chapel was conveyed in a subtle play of attitudes, gestures and rites, a symbolic choreography that accompanied and expressed the claims of the partisans and adversaries of the exemption of the royal place of worship with regard to the diocese of Paris. This stance was reflected in the decorative scheme of the palace’s final chapel, completed in 1710.

  12. Stability under irradiation of a fine dispersion of oxides in a ferritic matrix; Stabilite sous irradiation de particules d'oxydes finement dispersees dans des alliages ferritiques

    Monnet, I

    1999-07-01

    Oxide dispersion strengthened (ODS) ferritic-martensitic steels are being considered for high temperature, high fluence nuclear applications, like fuel pin cladding in Fast Breeder Reactors. ODS alloys offer improved out of pile strength characteristics at temperature above 550 deg.C and ferritic-martensitic matrix is highly swelling resistant. A clad in an ODS ferritic steel, call DY (Fe-13Cr-1,5Mo+TiO{sub 2}+Y{sub 2}O{sub 3}) has been irradiated in the experimental reactor Phenix. Under irradiation oxide dissolution occurs. Microstructural observations indicated that oxide evolution is correlated with the dose and consist in four phenomena: the interfaces of oxide particles with the matrix become irregular, the uniform distribution of the finest oxide (< 20 nm) disappear, the modification of oxide composition, and a halo of fine oxides appear around the larger oxides. The use of such a material requires a study of oxide stability under irradiation, since the oxide particles provide the desired mechanical properties. The study is based on two types of alloys, the DY and four ferritic steels Fe-9Cr-1Mo reinforced by Al{sub 2}O{sub 3}, Y{sub 2}O{sub 3}, MgO or MgAl{sub 2}O{sub 4}. These materials were irradiated with charged particles in order to gain a better understanding of the mechanisms of dissolution. Irradiation with 1 MeV Helium does not induce any modification, neither in the chemical modification of the particles nor in their spatial and size distribution. Since most of the energy of helium ions is lost by inelastic interaction, this result proves that this kind of interaction does not induce oxide dissolution. Irradiation with 1 MeV or 1.2 MeV electrons leads to a significant dissolution with a radius decrease proportional to the dose. These experiments prove that oxide dissolution can be induced by Frenkel pairs alone, provided that metallic atoms are displaced. The comparison between irradiation with ions (displacements cascades) and electrons (Frenkel pairs only) shows the importance of free point defects in the dissolution phenomena. For all the irradiations (ions or electrons) the spinel MgAl{sub 2}O{sub 4} seems more resistant than Y{sub 2}O{sub 3} to dissolution, and MgO and Al{sub 2}O{sub 3} are even less resistant. This is the order of stability under irradiation of bulk oxides. (author)

  13. Sélection immunomagnétique des lymphocytes T antiviraux IFN-[gamma]+ : analyse quantitative, fonctionnelle et composition en sous-populations lymphocytaires T

    Wang , Yingying

    2014-01-01

    Allogeneic hematopoietic stem cell transplantation (HSCT) is the standard treatment for malignant or non-malignant hematological disorders or primary immunodeficiencies. However, microbiological infections especially viral infections are the major cause for morbidity and mortality for the patients after HSCT except the GvHD and disease relapse. It comes often in the period of absence of cellular immunity when the antiviral treatment is not always efficiency with an important toxicity. So the ...

  14. Transport de pétroles bruts lourds sous forme d'émulsion huile dans eau Transporting Heavy Crude Oils in Oil in Water Emulsions

    Briant J.

    2006-11-01

    Full Text Available Des études préliminaires concernant le comportement visqueux d'émulsions d'un pétrole lourd très visqueux (Boscan, Venezuela dans de l'eau additionnée d'un tensioactif anionique ont été réalisées. Elles montrent que, pour la gamme des vitesses de cisaillement existant dans le transport par oléoduc, des réductions de viscosité de plusieurs ordres de grandeur par rapport à la viscosité du pétrole peuvent être obtenues avec des fractions volumiques de la phase dispersée de l'ordre de 60 %. This article describes a preliminary research on the viscous behavior of emulsions of a highly viscous heavy crude oil (Boscan, Venezuela in water containing an anionic surfactant. In the range of the shear rates usually encountered in pipelines, it is shown that the viscosity can be reduced by several orders of magnitude as compared with the crude oil viscosity, and th is for volume fractions of the dispersed phase in the range of 60%.

  15. Internal targeted radiotherapy for bone metastasis: what about underlying physiopathology; Radiotherapie interne vectorisee (metabolique) des metastases osseuses: quid de la physiopathologie sous-jacente?

    Vuillez, J.Ph. [Centre Hospitalier Universitaire, Hopital Michallon, Service de Biophysique et Medecine Nucleaire, 38 - Grenoble (France); Laval, G. [Centre Hospitalier Universitaire, Hopital Michallon, Unite de Recherche et de Soutien en Soins Palliatifs, 38 - Grenoble (France)

    2006-03-15

    Once tumours metastasize to bone, they are usually incurable and responsible for several devastating consequences: severe pain, pathologic fractures, life-threatening hypercalcemia, spinal cord compression and other nerve-compression syndromes. Understanding of physiopathological mechanisms responsible for these symptoms is critical for therapeutic approach, especially pain treatments. Three types of pain occur in tumour bone involvement: tonic or background pain, which are deep non-specific ache rising in intensity as the disease progresses; incident pain on movement (allodynia); and spontaneous pain which can be severe. Bone metastases could be osteolytic or osteoblastic. However, this classification actually represents two extremes of a continuum characterized by dys-regulation of the normal bone remodeling process. Biochemical mediators production is crucial as a part of this process. The bone microenvironment plays a critical role in the formation of osteoclasts through the production of macrophage colony-stimulating factor, receptor activator of nuclear factor kB ligand (RANKL)... Many of these mediators of osteolysis also have been shown to activate nociceptors: prostaglandins A and E, IL-1, IL-6, TNF. Thus there is a link between osteolytic destruction, inflammation and pain. It explains that severe pain could occur independently from fractures and in absence of any bone structure alteration and nervous compression. Also, pain is often disproportionate to tumour size or degree of bone involvement. Inflammatory and osteolytic processes depend on number, localization and organization of tumour cells inside bone and bone marrow tissues. All these parameters are crucial to take into account for a good understanding of treatments mechanisms of action, especially anti-inflammatory drugs (corticosteroid and others), bi-phosphonates, internal radiotherapy (strontium 89 or radiolabelled bi-phosphonates), external radiotherapy and chemotherapy or hormonotherapy). (author)

  16. Experimental and theoretical study of phase transitions under ball milling; Etude experimentale et modelisation des changements de phases sous broyage a haute energie

    Pochet, P

    1997-12-31

    The aim of this work was to determine how phase transition s under ball-milling depend on the milling conditions and to find out if one can rationalize such transitions with the theory of driven alloys. We have chosen two phase transitions: the order-disorder transition in Fe Al and the precipitation-dissolution NiGe. In the case of Fe Al we have found that the steady-state long range order parameter achieved under ball milling intensity; moreover the same degree of order is achieved starting from an ordered alloy or a disordered solid solution. On the way to fully disordered state the degree of order either decreases monotonically or goes through a short lived transient state. This behaviour is reminiscent of a first order transition while the equilibrium transition is second order. All the above features are well reproduced by a simple model of driven alloys, which was originally build for alloys under irradiation. The stationary degree of order results of two competitive atomic jump mechanisms: the forced displacements induced by the shearing of the grains, and the thermally activated jumps caused by vacancies migrations. Finally we have performed atomistic simulations with a Monte Carlo kinetic algorithm, which revealed the role of the fluctuations in the intensity of the forcing. Moreover we have shown that specific atomistic mechanisms are active in a dilute NiGe solid solution which might lead to ball milling induced precipitation in under-saturated solid solution. (author). 149 refs.

  17. Migration under irradiation of the I, Cs fission products in SiC; Migration sous irradiation des produits de fission I, Cs dans SiC

    Benyagoub, A. [Paris-11 Univ., 91 - Orsay (France). Centre de Spectrometrie Nucleaire et de Spectrometrie de Masse; Centre Interdisciplinaire de Recherche Ions Lasers (CIRIL), 14 - Caen (France)

    2007-07-01

    This work is a part of the CEA-CNRS program on the behaviour of materials under irradiation. Its aim is to contribute to scientifically base the predicting methods of the behaviour of ceramic materials under irradiation in using the important development of calculation means. In particular, its role has been 1)to develop the basic knowledge and the interactions physics and 2)to elaborate calculation models at relevant scales. The studied topics are until now, the damage mechanisms, the diffusion under irradiation, the micro-structural evolutions and the incidences on the mechanical properties. (O.M.)

  18. Study of boron carbide evolution under neutron irradiation; Contribution a l'etude de l'evolution du carbure de bore sous irradiation neutronique

    Simeone, D. [CEA/Saclay, Dept. de Mecanique et de Technologie (DMT), 91 - Gif-sur-Yvette (France)]|[Universite Blaise Pascal, Clermont-Ferrand II, (CNRS), 63 - Aubiere (France)

    1999-07-01

    Owing to its high neutron efficiency, boron carbide (B{sub 4}C) is used as a neutron absorber in control rods of nuclear plants. Its behaviour under irradiation has been extensively studied for many years. It now seems clear that brittleness of the material induced by the {sup 10}B(n,{alpha}){sup 7}Li capture reaction is due to penny shaped helium bubbles associated to a high strain field around them. However, no model explains the behaviour of the material under neutron irradiation. In order to build such a model, this work uses different techniques: nuclear microprobe X-ray diffraction profile analysis and Raman and Nuclear Magnetic Resonance Spectroscopy to present an evolution model of B{sub 4}C under neutron irradiation. The use of nuclear reactions produced by a nuclear microprobe such as the {sup 7}Li(p,p'{gamma}){sup 7}Li reaction, allows to measure lithium profile in B{sub 4}C pellets irradiated either in Pressurised Water Reactors or in Fast Breeder Reactors. Examining such profiles enables us to describe the migration of lithium atoms out of B{sub 4}C materials under neutron irradiation. The analysis of X-ray diffraction profiles of irradiated B{sub 4}C samples allows us to quantify the concentrations of helium bubbles as well as the strain fields around such bubbles.Furthermore Raman spectroscopy studies of different B{sub 4}C samples lead us to propose that under neutron irradiation. the CBC linear chain disappears. Such a vanishing of this CBC chain. validated by NMR analysis, may explain the penny shaped of helium bubbles inside irradiated B{sub 4}C. (author)

  19. Les dossiers de pensions des troupes coloniales et indigènes. La sous-série GR 13 Yf 

    HEISER, Sandrine; Guillot, Hélène

    2013-01-01

    En avril 2011, le Service historique de la Défense (SHD) a débuté le classement des dossiers de pensions des troupes coloniales et des troupes indigènes pour la période 1850-1950. 14 000 premiers dossiers ont été inventoriés, sur un total de 24 000, l’objectif étant d’achevé le classement pour le centenaire de la Grande Guerre. L’opération comporte également une phase importante de reconditionnement permettant une communication immédiate et idéale aux lecteurs au gré des mises à jour régulièr...

  20. Report by the 'Mega-earthquakes and mega-tsunamis' subgroup; Rapport du sous-groupe Sismique 'Megaseismes et megatsunamis'

    Friedel, Jacques; Courtillot, Vincent; Dercourt, Jean; Jaupart, Claude; Le Pichon, Xavier; Poirier, Jean-Paul; Salencon, Jean; Tapponnier, Paul; Dautray, Robert; Carpentier, Alain; Taquet, Philippe; Blanchet, Rene; Le Mouel, Jean-Louis [Academie des sciences, 23, quai de Conti, 75006 Paris (France); BARD, Pierre-Yves [Observatoire des sciences de l' Univers de l' universite de Grenoble - OSUG, Universite Joseph Fourier, BP 53, 38041 Grenoble Cedex 9 (France); Bernard, Pascal; Montagner, Jean-Paul; Armijo, Rolando; Shapiro, Nikolai; Tait, Steve [Institut de physique du globe de Paris, 1, rue Jussieu - 75238 Paris cedex 05 (France); Cara, Michel [Ecole et Observatoire des sciences de la Terre de l' universite de Strasbourg - EOST, F-67084 Strasbourg cedex (France); Madariaga, Raul [Ecole normale superieure, 45, rue d' Ulm / 29, rue d' Ulm, F-75230 Paris cedex 05 (France); Pecker, Alain [Academie des technologies, Grand Palais des Champs Elysees - Porte C - Avenue Franklin D. Roosevelt - 75008 Paris (France); Schindele, Francois [CEA/DAM, DIF/DASE/SLDG, 91297 ARPAJON Cedex (France); Douglas, John [BRGM, 3 avenue Claude-Guillemin - BP 36009 - 45060 Orleans Cedex 2 (France)

    2011-06-15

    This report comprises a presentation of scientific data on subduction earthquakes, on tsunamis and on the Tohoku earthquake. It proposes a detailed description of the French situation (in the West Indies, in metropolitan France, and in terms of soil response), and a discussion of social and economic issues (governance, seismic regulation and nuclear safety, para-seismic protection of constructions). The report is completed by other large documents: presentation of data on the Japanese earthquake, discussion on prediction and governance errors in the management of earthquake mitigation in Japan, discussions on tsunami prevention, on needs of research on accelerometers, and on the seismic risk in France

  1. Incisional subcutaneous endometrioma of the abdominal wall: report of two cases; Endometriose sous cutanee sur cicatrice de la paroi abdominale anterieure. A propos de deux observations

    Merran, S.; Karila-Cohen, P. [Federation Mutualiste Parisienne, Dept. d' Imagerie Medicale, 75 - Paris (France)

    2004-04-01

    Endometriosis occurs in up to 15% of menstruating women. Abdominal wall involvement is rare and always secondary to an invasive procedure. The authors report the imaging and clinical findings of two patients with subcutaneous endometrioma following cesarean section. (author)

  2. Migration of hydrocarbons in the subsoil of an industrial installation; Migration d'hydrocarbures dans le sous-sol d'une installation industrielle

    Van Dorpe, F [CEA Cadarache, Dept. d' Entreposage et de Stockage des Dechets (DCC/DESD/SEP), 13 - Saint-Paul-lez-Durance (France); Centre National de Recherche sur les Sites et Sols Pollues (CNRSSP), 59 - Douai (France)

    2000-07-01

    The fate of old industrial sites is a major problem at the beginning of the new millennium for government organization, agencies owning polluted sites... These brown-field sites often generate considerable pollution of soils and groundwater, the main source of drinking water. The National Center for Research on Polluted Soils and Sites (CNRSSP), in which the CEA is an active partner, is developing a strategy to study and, using several scientific tools, characterize industrial sites polluted by various contaminants: metals, metalloids, hydrocarbons, nitrates. The present study offers an example of the investigation of an old industrial site (coke plant), built in 1919 (in operation for 50 years), located in northern France. The storage of tars and wastewaters on these sites causes soil and groundwater contamination with organic compounds such as Polycyclic Aromatic Hydrocarbons (PAHs), mono-aromatic hydrocarbons (benzene, toluene, ethyl-benzene and xylene BTEX), volatile organic compounds (VOCs), phenolic and other hydrocarbons, and inorganic compounds including metalloids (free and complexed cyanides) and metals (As, Pb, Ni, Cd and Hg). The more soluble constituents tend to migrate to adjacent areas with the groundwater flow and thereby reach receptors such as drinking water resources. Among the above pollutants, the 16 PAHs from the priority list of the Environmental Protection Agency (EPA) are of great environmental concern due to their toxic, mutagenic and carcinogenic properties. The remediation of PAH-polluted sites poses a crucial challenge given the large number of sites contaminated by these pollutants and the difficulty in eliminating the pollution. A better evaluation of the PAH transfer and transport in soils and aquifers will also help draw up remediation strategies. In this study, a numerical model, called SIMUSCOPP and developed by the French Petroleum Institute (IFP), BURGEAP and ENI group for organic pollutants, was used to simulate 3D transfer and transport of PAHs under an old coke plant, taking biodegradation and soil sorption into account. The simulation results discussed in this paper were obtained by assuming tar pollution 7 m deep underground to be the only source. This aquifer pollution in a chalky formation mainly consists of PAHs (naphthalene, fluoranthene, etc). A broad field investigation was conducted on the site by monitoring the water (16 piezometers, piezometric measurements, pollutant concentration analysis) to characterize the location and extent of the PAH plume. The numerical modeling was aimed to characterize PAH migration in the unsaturated and saturated zones and to assess the vulnerability of a drinking water well located downstream. The model helped estimate the time for dissolved naphthalene to reach steady state (20 years) and the plume dimensions (1200 m long, 300 m wide and 15 m thick). Simulation were performed of water samplings in piezometers inside and outside the polluted area and the naphthalene concentration in water samples was reproduced, in good agreement with real observations on boreholes of the site. However, for two piezometers located between the two lagoons of coal tars, a large contribution of a second source of PAH, enriched in PAHs with 2 or 3 rings and located at the base of aquifer, was identified in water samples, in the pumped water. This significant share of the pollution is not transported with groundwater flow, but only with water pumping. Thus SIMUSCOPP served to identify the dissolved phase of PAH and to quantify the rest of the pollution, possibly a colloidal phase. As a consequence, a new water sampling strategy could be developed in order to adjust the pump discharge, use specific filters, etc. The major conclusion of the transport simulation is that the PAH plume does not reach the drinking water well located 4 km downstream of the site. However, some remediation measures are necessary and the polluted soils are currently being excavated. (author)

  3. Le maître d’ouvrage et le contrat de sous-traitance dans les marchés publics de travaux au Cameroun

    Lesmont Bahoken Valeri

    2015-12-01

    Full Text Available Any subcontracting in public procurement contracts is subject to the prior approval of the Contracting authority. This is a manifestation of excessive powers which holds the administration in public law contracts. Therefore, the public contract is liable to termination as soon as the Contracting authority finds by any means whatsoever subcontracting occult on the work site. However, as soon as subcontracting is allowed, the Contracting authority appears foreign to its implementation, leaving the parties freely fulfill their contractual obligations. The situation of the contractor who is generally a small business or PMI is abandoned to the will of the contracting party of the public person, usually powerful multinationals. The Contracting authority displays a certain neutrality in both the quality of work performed by the contractor in terms of payment of the latter. Contractual freedom seems to have taken precedence here on the powers of control and direction of which is coated the Contracting authority in the execution of public contract, to the detriment of the subcontractor. A reform of the Government Procurement Code and subsequent legislation is needed to better protect the interests of the subcontractor. This article is striving to clarify the relationship Contracting authority -Contractorsubcontractor in works contracts. It demonstrates that the subcontractor weaker party to the contract must be better protected so as to safeguard the contractual solidarism which seems to be based the existence of the outsourcing contract.

  4. Oligo cyclic plastic fatigue of Zircaloy-4 under vacuum and in iodinated methanol; Fatigue plastique oligocyclique du Zircaloy-4 sous vide et dans le methanol iode

    Beloucif, A.

    1995-01-01

    Our study was bound to the Zircaloy-4 fuel can damage in PWR type reactors. The topic was the damage mechanisms of Zircaloy-4 by oligo-cyclic plastic fatigue in inert atmosphere and in iodinated methanol. The oligo-cyclic plastic fatigue tests, under vacuum, were performed with steady plastic deformation and deformation speed. The corrosion fatigue tests in iodinated methanol put to the fore one obvious harmful part of iodine on Zircaloy-4 resistance to cyclic solicitations. The observations proved the existence of a very strong synergic effect between cyclic mechanical damage and corrosion. (MML). 84 refs., 117 figs., 3 tabs.

  5. Alteration mechanisms of UOX spent fuel under water; Mecanismes d'alteration sous eau du combustible irradie de type UOX

    Muzeau, B

    2008-06-15

    The mechanisms of spent fuel alteration in aqueous media need to be understood on the assumption of a direct disposal of the assemblies in a geological formation or for long duration storage in pool. This work is a contribution to the study of the effects of the alpha and/or beta/gamma radiolysis of water on the oxidation and the dissolution of the UO{sub 2} matrix of UOX spent fuel. The effects of the alpha radiolysis, predominant in geological disposal conditions, were quantified by using samples of UO{sub 2} doped with plutonium. The leaching experiments highlighted two types of control for the matrix alteration according to the alpha activity. The first is based on the radiolytic oxidation of the surface and leads to a continuous release of uranium in solution whereas the second is based on a control by the solubility of uranium. An activity threshold, between 18 MBq.g{sup -1} and 33 MBq.g{sup -1}, was defined in a carbonated water. The value of this threshold is dependent on the experimental conditions and the presence or not of electro-active species such as hydrogen in the system. The effects of the alpha/beta/gamma radiolysis in relation with the storage conditions were also quantified. The experimental data obtained on spent fuel indicate that the alteration rate of the matrix based on the behaviour of tracer elements (caesium and strontium) reached a maximum value of some mg.m{sup -2}.d{sup -1}, even under very oxidizing conditions. The solubility of uranium and the nature of the secondary phases depend however on the extent of the oxidizing conditions. (author)

  6. Alteration mechanisms of UOX spent fuel in aqueous media; Mecanismes d'alteration sous eau du combustible irradie de type UOX

    Muzeau, B

    2007-06-15

    The mechanisms of underwater alteration of spent fuels need to be understood on the assumption of a direct disposal of the assemblies in a geological formation or for long duration storage in pool. This work is a contribution to the study of the effects of the alpha and/or beta/gamma radiolysis of water on the oxidation and the dissolution of the UO{sub 2} matrix of UOX spent fuel. The effects of the alpha radiolysis, predominant in geological disposal conditions, were quantified using samples of UO{sub 2} doped with plutonium. The leaching experiments highlighted two types of control for the matrix alteration according to the alpha activity. The first is based on the radiolytic oxidation of the surface and leads to a continuous release of uranium in solution whereas the second is based on a control by the solubility of uranium. An activity threshold, located between 18 MBq/g and 33 MBq/g, was defined in a carbonated water. The value of this threshold is dependent on the experimental conditions and the presence or not of electro-active species such as hydrogen in the system. The effects of the alpha/beta/gamma radiolysis in relation with the storage conditions were also quantified. The experimental data obtained on spent fuel indicate that the alteration rate of the matrix based on the behaviour of tracer elements (caesium and strontium) reached a maximum value of some mg.m{sup -2}.d{sup -1}, even under very oxidizing conditions. The solubility of uranium and the nature of the secondary phases depend however on the extent of the oxidizing conditions. (author)

  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

    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. Modeling brine-rock interactions in an enhanced geothermal systemdeep fractured reservoir at Soultz-Sous-Forets (France): a joint approachusing two geochemical codes: frachem and toughreact

    Andre, Laurent; Spycher, Nicolas; Xu, Tianfu; Vuataz,Francois-D.; Pruess, Karsten.

    2006-12-31

    The modeling of coupled thermal, hydrological, and chemical (THC) processes in geothermal systems is complicated by reservoir conditions such as high temperatures, elevated pressures and sometimes the high salinity of the formation fluid. Coupled THC models have been developed and applied to the study of enhanced geothermal systems (EGS) to forecast the long-term evolution of reservoir properties and to determine how fluid circulation within a fractured reservoir can modify its rock properties. In this study, two simulators, FRACHEM and TOUGHREACT, specifically developed to investigate EGS, were applied to model the same geothermal reservoir and to forecast reservoir evolution using their respective thermodynamic and kinetic input data. First, we report the specifics of each of these two codes regarding the calculation of activity coefficients, equilibrium constants and mineral reaction rates. Comparisons of simulation results are then made for a Soultz-type geothermal fluid (ionic strength {approx}1.8 molal), with a recent (unreleased) version of TOUGHREACT using either an extended Debye-Hueckel or Pitzer model for calculating activity coefficients, and FRACHEM using the Pitzer model as well. Despite somewhat different calculation approaches and methodologies, we observe a reasonably good agreement for most of the investigated factors. Differences in the calculation schemes typically produce less difference in model outputs than differences in input thermodynamic and kinetic data, with model results being particularly sensitive to differences in ion-interaction parameters for activity coefficient models. Differences in input thermodynamic equilibrium constants, activity coefficients, and kinetics data yield differences in calculated pH and in predicted mineral precipitation behavior and reservoir-porosity evolution. When numerically cooling a Soultz-type geothermal fluid from 200 C (initially equilibrated with calcite at pH 4.9) to 20 C and suppressing mineral precipitation, pH values calculated with FRACHEM and TOUGHREACT/Debye-Hueckel decrease by up to half a pH unit, whereas pH values calculated with TOUGHREACT/Pitzer increase by a similar amount. As a result of these differences, calcite solubilities computed using the Pitzer formalism (the more accurate approach) are up to about 1.5 orders of magnitude lower. Because of differences in Pitzer ion-interaction parameters, the calcite solubility computed with TOUGHREACT/Pitzer is also typically about 0.5 orders of magnitude lower than that computed with FRACHEM, with the latter expected to be most accurate. In a second part of this investigation, both models were applied to model the evolution of a Soultz-type geothermal reservoir under high pressure and temperature conditions. By specifying initial conditions reflecting a reservoir fluid saturated with respect to calcite (a reasonable assumption based on field data), we found that THC reservoir simulations with the three models yield similar results, including similar trends and amounts of reservoir porosity decrease over time, thus pointing to the importance of model conceptualization. This study also highlights the critical effect of input thermodynamic data on the results of reactive transport simulations, most particularly for systems involving brines.

  9. Study of secondary electron emission from thin carbon targets with swift charged particles: heavy ions, hydrogen ions; Etude experimentale de l`emission electronique secondaire de cibles minces de carbone sous l`impact de projectiles rapides: ions lourds, ions hydrogene (atomiques, moleculaires ou sous forme d`agregats)

    Billebaud, A

    1995-07-12

    The main subject of this work is the study of electron emission from the two surfaces of thin solid targets bombarded with swift charged particles. The slowing down of swift ions in matter is mainly due to inelastic interaction with target electrons (ionization, excitation): the energy transfer to target electrons is responsible for the secondary electron emission process. The phenomenological and theoretical descriptions of this phenomena are the subject of the first chapter. We focused on secondary electron emission induced by different kind of projectiles on thin carbon foils. In chapter two we describe hydrogen cluster induced electron emission measurement between 40 and 120 keV/proton. These projectiles, composed of several atoms, allowed us to study and highlight collective effects of the electron emission process. We extended our study of electron emission to molecular (H{sub 2}{sup +}, H{sub 3}{sup +}) and composite (H{sup -}, H{sup 0}) projectiles at higher energies (<= 2 MeV): we have designed an experimental set-up devoted to electron emission statistics measurements which allowed us to study, among others things, the role of projectile electrons in secondary electron emission. This experiment is described in the third chapter. Finally, the fourth chapter describes new measurements of electron emission induced by energetic (13 MeV/u) and highly charged argon ion provided by the medium energy beam line (SME) of GANIL (Caen), which have been analyzed in the framework of a semi-empirical model of secondary electron emission. This set of experiments brings new results on composite projectile interaction with matter, and on the consequences of high energy deposition in solids. (author).

  10. Metallurgical and mechanical parameters controlling alloy 718 stress corrosion cracking resistance in PWR primary water; Facteurs metallurgiques et mecaniques controlant l'amorcage de defauts de corrosion sous contrainte dans l'alliage 718 en milieu primaire des reacteurs a eau sous pression

    Deleume, J

    2007-11-15

    Improving the performance and reliability of the fuel assemblies of the pressurized water reactors requires having a perfect knowledge of the operating margins of both the components and the materials. The choice of alloy 718 as reference material for this study is justified by the industrial will to identify the first order parameters controlling the excellent resistance of this alloy to Stress Corrosion Cracking (SCC). For this purpose, a specific slow strain rate (SSR) crack initiation test using tensile specimen with a V-shaped hump in the middle of the gauge length was developed and modeled. The selectivity of such SSR tests in simulated PWR primary water at 350 C was clearly established by characterizing the SCC resistance of nine alloy 718 thin strip heats. Regardless of their origin and in spite of a similar thermo-mechanical history, they did not exhibit the same susceptibility to SCC crack initiation. All the characterized alloy 718 heats develop oxide scale of similar nature for various exposure times to PWR primary medium in the temperature range [320 C - 360 C]. {delta} phase precipitation has no impact on alloy 718 SCC initiation behavior when exposed to PWR primary water, contrary to interstitial contents and the triggering of plastic instabilities (PLC phenomenon). (author)

  11. Oligoptique (alias traceur.

    Laurent Devisme

    2007-07-01

    Full Text Available « Essayez plutôt avec cette orthographe : elliptique » ! Le moteur de recherche Google nous invite à passer notre chemin, tout en indiquant le texte d’une anthropologue commentant le travail d’Émilie Hermant et Bruno Latour, consigné dans Paris, ville invisible . C’est de fait dans la galaxie Latourienne que l’on rencontre le terme. Oligos, c’est le petit nombre, et l’optique est la science de la vision. En les associant, nous sommes sur la voie d’un oligoptique qui ne ...

  12. Prévision avec des copules en finance

    Charpentier , Arthur

    2015-01-01

    Cet article présente un survol les techniques usuelles de modélisation de séries nancières multiples. Pus spéciquement, on cherchera a obtenir une extention multivariée des modèles GARCH. Dans un premier temps, nous verrons comment modéliser la dynamique de la matrice de corrélation (conditionnelle), puis nous verrons comment généraliser cette approche à des lois conditionnelles plus générales, construites à l'aide de copules (et s'aranchir ainsi de l'hypothese de lois elliptiques). Les princ...

  13. Maitrise de la fermentation alcoolique sous stress éthanolique, thermique et osmotique de la souche Saccharomyces cerevisiae YS-DN1 en vue de la préparation du vinaigre de fruits

    Majid MOUNIR

    2016-07-01

    Full Text Available The purpose of the present study is to isolate, identify and characterize new yeast species of industrial interest. A total of 54 strains were isolated and identified from agricultural raw products and from by-products of the food industry. Among these, four strains were selected, purified and tested for their ability to perform efficient fermentation on Bouslikhène date juice. After the sequencing of the 18S gene of the ribosomal DNA, the two strains YS-DN1 and YS-M isolated respectively from dates and molasses have been identified belonging to Saccharomyces cerevisiae species. In addition, the other two strains, YS-OMP and YS-G isolated from olives and grapes belonged to Kluyveromyces marxianus (78% homology and Candida utilis (89% homology species, respectively. In addition, YS-DN1 strain showed the highest performance in terms of ethanol production in comparison with two other industrial reference strains. YS-DN1 strain was the only one that was able to grow at a temperature ranged from 35 to 40°C in the presence of a high alcoholic concentration and aggressive osmotic pressure condition. Finally, production of the cellular biomass of YS-DN1 strain was improved by optimization of temperature, Brix and pH fixed respectively at 29.75°C, 15.7% and 4.15. These values allowed to obtain a maximum of cells of about 8.4x10 8 UFC/ml. It was concluded that this strain is well suited for fruit vinegar production at a large-scale.

  14. Theoretical study of silicon carbide under irradiation at the nano scale: classical and ab initio modelling; Etude theorique a l'echelle nanometrique du carbure de silicium sous irradiation: modelisation classique et ab initio

    Lucas, G

    2006-10-15

    The behaviour of silicon carbide under irradiation has been studied using classical and ab initio simulations, focusing on the nano scale elementary processes. First, we have been interested in the calculation of threshold displacement energies, which are difficult to determine both experimentally and theoretically, and also the associated Frenkel pairs. In the framework of this thesis, we have carried out simulations in classical and ab initio molecular dynamics. For the classical approach, two types of potentials have been used: the Tersoff potential, which led to non satisfactory results, and a new one which has been developed during this thesis. This potential allows a better modelling of SiC under irradiation than most of the empirical potentials available for SiC. It is based on the EDIP potential, initially developed to describe defects in silicon, that we have generalized to SiC. For the ab initio approach, the feasibility of the calculations has been validated and average energies of 19 eV for the C and 38 eV for the Si sublattices have been determined, close to the values empirically used in the fusion community. The results obtained with the new potential EDIP are globally in agreement with those values. Finally, the elementary processes involved in the crystal recovery have been studied by calculating the stability of the created Frenkel pairs and determining possible recombination mechanisms with the nudged elastic band method. (author)

  15. Interaction of ultra-short ultra-intense laser pulses with under-dense plasmas; Interaction d'impulsions laser ultra-courtes et ultra-intenses avec des plasmas sous denses

    Solodov, A

    2000-12-15

    Different aspects of interaction of ultra-short ultra-intense laser pulses with underdense plasmas are studied analytically and numerically. These studies can be interesting for laser-driven electron acceleration in plasma, X-ray lasers, high-order harmonic generation, initial confinement fusion with fast ignition. For numerical simulations a fully-relativistic particle code WAKE was used, developed earlier at Ecole Polytechnique. It was modified during the work on the thesis in the part of simulation of ion motion, test electron motion, diagnostics for the field and plasma. The studies in the thesis cover the problems of photon acceleration in the plasma wake of a short intense laser pulse, phase velocity of the plasma wave in the Self-Modulated Laser Wake-Field Accelerator (SM LWFA), relativistic channeling of laser pulses with duration of the order of a plasma period, ion dynamics in the wake of a short intense laser pulse, plasma wave breaking. Simulation of three experiments on the laser pulse propagation in plasma and electron acceleration were performed. Among the main results of the thesis, it was found that reduction of the plasma wave phase velocity in the SM LWFA is crucial for electron acceleration, only if a plasma channel is used for the laser pulse guiding. Self-similar structures describing relativistic guiding of short laser pulses in plasmas were found and relativistic channeling of initially Gaussian laser pulses of a few plasma periods in duration was demonstrated. It was shown that ponderomotive force of a plasma wake excited by a short laser pulse forms a channel in plasma and plasma wave breaking in the channel was analyzed in detail. Effectiveness of electron acceleration by the laser field and plasma wave was compared and frequency shift of probe laser pulses by the plasma waves was found in conditions relevant to the current experiments. (author)

  16. Catalysis under Irradiation in the Presence of Non-Metallic Solids; Catalyse sous irradiation en presence de solides non metalliques; Radiatsionnyj kataliz pri nalichii'nemetallicheskikh tverdykh tel; Radiocatalisis en presencia de solidos no metalicos

    Coekelbergs, R.; Crucq, A.; Decot, J.; Degols, L.; Frennet, A.; Lienard, G.; Timmerman, L. [Laboratoire de Chimie Nucleaire, Institut Interuniversitaire des Sciences Nucleaires et Ecole Royale Militaire, Bruxelles (Belgium)

    1963-11-15

    Catalytic processes induced by radiation in the presence of non-metallic solids are discussed, attention being given exclusively to the effects associated with modification of the steady state concentration of charge carriers. The effect of such modification on the kinetics and equilibrium of heterogeneous reactions is quantitatively estimated within the framework of the electronic theory of catalysis, due regard being paid to the electronic characteristics of the surface of the solid. In conclusion, the relationship between these phenomena, catalyst activation and transfer of energy, as previously described, is discussed. (author) [French] Les auteurs discutent des processus catalytiques induits par les radiations en presence de solides non metalliques. Ils considerent exclusivement les effets lies a la modification de la concentration stationnaire des porteurs de charge.- L'influence de cette modification sur la cinetique et l'equilibre des reactions heterogenes est evaluee quantitativement dans le cadre de la theorie electronique de la catalyse et en tenant compte de caracteristiques electroniques de la surface du solide. Enfin, ils discutent la relation existant entre ces phenomenes, l'activation des catalyseurs et le transfert d'energie decrits anterieurement. (author) [Spanish] Los autores examinan los procesos cataliticos inducidos por las radiaciones en presencia de solidos no metalicos. Consideran exclusivamente los efectos vinculados con la modificacion de la concentracion estacionaria de los portadores de carga. Sobre la base de la teoria electronica de la catalisis y teniendo en cuenta las caracteristicas electronicas de la superficie del solido, determinan cuantitativamente la influencia de aquella modificacion sobre la cinetica y el equilibrio de las reacciones heterogeneas. Por ultimo, analizan la relacion que existe entre estos fenomenos, la activacion de los catalizadores y la transmision de energia descritas anteriormente. (author) [Russian] Avtory obsuzhdayut protsessy kataliza, indutsirovannye radiatsiej v prisutstvii nemetallicheskikh tverdykh tel. Oni rassmatrivayut isklyuchitel'no tol'ko dejstviya, svyazannye s izmeneniem postoyannoj kontsentratsii nositelej zaryada. Vliyanie ehtogo izmeneniya na kinetiku i ravnovesie geterogennykh reaktsij rasschityvaetsya kolichestvenno v ramkakh ehlektronnoj teorii kataliza i uchityvaya ehlektronnye kharakteristiki poverkhnosti tverdogo tela. Nakonets, oni rassmatrivayut sootnoshenie, sushchestvuyushchee mezhdu ehtimi yavleniyami, aktivatsiej katalizatorov i peredachej ehnergii, opisannymi ranee. (author)

  17. Electrodéposition sous champ magnétique de zinc et de fer.Propriétés magnétiques des arborescences de fer

    Heresanu , Vasile

    2003-01-01

    President du jury: A. Alemany ; Raporteurs : J-P. Chopart, J.M.D. Coey ; Examinateurs : J-L. Porteseil, R. Ballou, P. Molho; This work is concerned with the effects of magnetic fields on arborescence of zinc and iron obtained by electrochemical deposition in thin cell and with the magnetic properties of iron arborescences. For zinc under normal magnetic field, the macroscopic morphology changes are explained by the mechanical action, on the growing aggregate, of fluid convection induced by th...

  18. Physical properties of high-Tc superconducting oxides. Modification of tc using organic dopants. Final report. Proprietes physiques d'oxydes supraconducteurs a haute Tc. Modification de tc sous l'effet de dopants organiques

    Brau, A

    1993-01-01

    An attempt was made to significantly modify the Tc transition temperature of certain copper-based superconducting oxides by introducing organic or mineral dopants, and to study the mobility of 300K-carriers in crystallized tallium-base superconducting oxides. Since the critical transition temperature of superconducting oxides is highly influenced by the density of the free carriers they contain, the authors tried making superconducting powders react with either an organic electron acceptor or a mineral compound. The goal was to increase the density of the holes by altering the copper's degree of oxidation. Their preparatory work showed a direct charge-transfer reaction between the electron-donor copper and the acceptor TCNQ and studied the degree to which the electron acceptor can alter the copper's oxidation. Initial results also showed that dopants can affect superconducting Tc and the course of R(T) curves.

  19. Electrochemical treatment of an oxide material, application to superconductors, and obtained superconductors. Procede de traitement electrochimique d'un materiau sous forme oxyde, application aux supraconducteurs et supraconducteurs ainsi obtenus

    Grenier, J C; Pouchard, M; Wattiaux, A

    1991-06-07

    The present invention describes the electrochemical treatment of a superconductor oxide so as to modify its stoichiometry. These materials comprise in their anionic lattice oxygenated and hydrogenated species. These treated materials are prepared by an electrochemical process in which the oxide is an electrode in a liquid electrolysis. 3 refs., 3 figs.

  20. Development of radiotracers for imaging NR2B subtype NMDA receptors with positron emission tomography; Developpement de radiotraceurs pour la visualisation des recepteurs NMDA de sous-type NR2B par tomographie par emission de positons

    Labas, R

    2007-07-01

    The aim of this thesis was to develop new radioactive tracers for imaging NR2B subtype NMDA receptors with positron emission tomography. Several compounds including 4-(4-fluoro-benzyl)piperidine and presenting interesting in vivo biological properties were the object of a labelling with a positrons emitter atom ({sup 11}C or {sup 18}F)

  1. Cyclic plasticity of an austenitic-ferritic stainless steel under biaxial non proportional loading; Plasticite cyclique d'un acier inoxydable austeno-ferritique sous chargement biaxial non-proportionnel

    Aubin, V

    2001-11-15

    Austenitic-ferritic stainless steels are supplied since about 30 years only, so they are yet not well-known. Their behaviour in cyclic plasticity was studied under uniaxial loading but not under multiaxial loading, whereas only a thorough knowledge of the phenomena influencing the mechanical behaviour of a material enables to simulate and predict accurately its behaviour in a structure. This work aims to study and model the behaviour of a duplex stainless steel under cyclic biaxial loading. A three step method was adopted. A set of tension-torsion tests on tubular specimen was first defined. We studied the equivalence between loading directions, and then the influence of loading path and loading history on the stress response of the material. Results showed that duplex stainless steel shows an extra-hardening under non proportional loading and that its behaviour depends on previous loading. Then, in order to analyse the results obtained during this first experimental stage, the yield surface was measured at different times during cyclic loading of the same kind. A very small plastic strain offset (2*10{sup -5}) was used in order not to disturb the yield surface measured. The alteration of isotropic and kinematic hardening variables were deduced from these measures. Finally, three phenomenological constitutive laws were identified with the experimental set. We focused our interest on the simulation of stabilized stress levels and on the simulation of the cyclic hardening/softening behaviour. The comparison between experimental and numerical results enabled the testing of the relevance of these models. (authors)

  2. Construction of transmission pipeline across Osaka bay area -pipeline construction by shield tunnel under seabed-; Construction d'un gazoduc dans la zone de la baie d'Osaka - tunnel de protection sous-marin

    Takashi, AIhara [Osaka Gas Co., Ltd (Japan)

    2000-07-01

    Osaka Gas has been constructing a transmission gas pipeline across Osaka Bay Area with Osaka Port that has busy traffic. The company met several technical problems on the construction-design with measures against the subsidence of reclaimed land, anti-seismic measures, for example, in designing the pipeline construction by shield tunnel under seabed. This paper introduces the solutions to the technical problems. (authors)

  3. Micro-mechanical modeling of the growth/percolation of pressurized pores in a ceramic matrix at high temperatures; Modelisation micromecanique de la croissance et de la percolation de pores sous pression dans une matrice ceramique a haute temperature

    Vincent, P.G

    2007-11-15

    The aim of this work is to propose an elasto-plastic model of damage in a porous ceramics containing two populations of saturated cavities: the nuclear fuel uranium dioxide highly irradiated and at high temperature. The followed approach consists in a multi-scale approach based on the hypothesis of separation of the scales between the two populations of cavities (spherical intragranular pores and spheroidal intergranular pores) and of those of the macroscopic isotropy. The proposed elasto-plastic model of damage treats separately of the elasticity, of the surface of plasticity and of the evolution of the internal parameters of the model with load. The taking into account of different pressures in each population of cavity is carried out for elasticity-plasticity-damage. The model developed for the elastic behaviour takes into account the two populations of cavity, their morphology, their distribution and the pore pressures inside them. The proposed plasticity criteria is based on homogenization methods for non linear behaviours. At the grain scale, the first population of cavity is taken into account by a plasticity criteria of Gurson-Tvegaard-Needleman type. At the scale of grains collection, the presence of a second population of cavity inside a compressible matrix leads to the development of new superior boundaries and pertaining estimations for the effective plasticity surface. These models depend on the morphology and of the distribution of cavities. In the case of drained cavities, an analytical estimation, based on the writing of the classical variational principle with a compressible velocity field and an average on the equiprobable orientations is developed. In the case of saturated cavity, another estimation, based on the variational approach of Ponte Castaneda (1991) with a linear N phases comparison composite is proposed. These models are compared to numerical simulations by finite elements and to numerical simulations using the fast Fourier transformation method. The evolution laws of the retained elasto-plastic model (the estimation at N phases) are established on hypotheses of middle conservation of the cavities morphologies. An a posteriori enrichment of the evolution law of the porosity at the second scale is carried out by numerical simulations which are relative to the studied material. These numerical simulations allow to study the coalescence of the voids of the second scale (the percolation term is assimilated to the coalescence phenomenon) and implement a volume/cohesive finite element method on periodical Voronoi cells. (O.M.)

  4. Quantitative characterization of initiation and propagation in stress corrosion cracking. An approach of a phenomenological model; Caracterisation quantitative de l`amorcage et de la propagation en corrosion sous contrainte. Approche d`une modelisation phenomenologique

    Raquet, O

    1994-11-25

    A purely phenomenological study of stress corrosion cracking was performed using the couple Z2CN 18.10 (304L) austenitic stainless steel/boiling MgCl{sub 2} aqueous solution. The exploitation of the morphological information (shape of the cracks and size distribution) available after constant elongation rate tests led to the proposal of an analytical expression of the crack initiation and growth rates. This representation allowed to quantitatively characterize the influence of the applied strain rate as well as the effect of corrosion inhibitors on the crack initiation and propagation phases. It can be used in the search for the stress corrosion cracking mechanisms as a `riddle` for the determination of the rate controlling steps. As a matter of fact, no mechanistic hypothesis has been used for its development. (author).

  5. Local approach: fracture at high temperature in an austenitic stainless steel submitted to thermomechanical loadings. Calculations and experimental validations; Approche locale: fissuration a haute temperature dans un acier inoxydable austenitique sous chargements thermomecaniques. Simulations numeriques et validations experimentales

    Poquillon, D

    1997-10-01

    Usually, for the integrity assessment of defective components, well established rules are used: global approach to fracture. A more fundamental way to deal with these problems is based on the local approach to fracture. In this study, we choose this way and we perform numerical simulations of intergranular crack initiation and intergranular crack propagation. This type of damage can be find in components of fast breeder reactors in 316 L austenitic stainless steel which operate at high temperatures. This study deals with methods coupling partly the behaviour and the damage for crack growth in specimens submitted to various thermomechanical loadings. A new numerical method based on finite element computations and a damage model relying on quantitative observations of grain boundary damage is proposed. Numerical results of crack initiation and growth are compared with a number of experimental data obtained in previous studies. Creep and creep-fatigue crack growth are studied. Various specimen geometries are considered: compact Tension Specimens and axisymmetric notched bars tested under isothermal (600 deg C) conditions and tubular structures containing a circumferential notch tested under thermal shock. Adaptative re-meshing technique and/or node release technique are used and compared. In order to broaden our knowledge on stress triaxiality effects on creep intergranular damage, new experiments are defined and conducted on sharply notched tubular specimens in torsion. These isothermal (600 deg C) Mode II creep tests reveal severe intergranular damage and creep crack initiation. Calculated damage fields at the crack tip are compared with the experimental observations. The good agreement between calculations and experimental data shows the damage criterion used can improve the accuracy of life prediction of components submitted to intergranular creep damage. (author) 200 refs.

  6. Comparative analysis of operation and safety of subcritical nuclear systems and innovative critical reactors; Analyse comparative du fonctionnement et de la surete de systemes sous-critiques et de reacteurs critiques innovants

    Bokov, P.M

    2005-05-01

    The main goal of this thesis work is to investigate the role of core subcriticality for safety enhancement of advanced nuclear systems, in particular, molten salt reactors, devoted to both energy production and waste incineration/transmutation. The inherent safety is considered as ultimate goal of this safety improvement. An attempt to apply a systematic approach for the analysis of the subcriticality contribution to inherent properties of hybrid system was performed. The results of this research prove that in many cases the subcriticality may improve radically the safety characteristics of nuclear reactors, and in some configurations it helps to reach the 'absolute' intrinsic safety. In any case, a proper choice of subcriticality level makes all analyzed transients considerably slower and monotonic. It was shown that the weakest point of the independent-source systems with respect to the intrinsic safety is thermohydraulic unprotected transients, while in the case of the coupled-source systems the excess reactivity/current insertion events remain a matter of concern. To overcome these inherent drawbacks a new principle of realization of a coupled sub-critical system (DENNY concept) is proposed. In addition, the ways to remedy some particular safety-related problems with the help of the core sub-criticality are demonstrated. A preliminary safety analysis of the fast-spectrum molten salt reactor (REBUS concept) is also carried out in this thesis work. Finally, the potential of the alternative (to spallation) neutron sources for application in hybrid systems is examined. (author)

  7. Appréhender le probléme historique de l'État sous l'approche de la culture politique. Éléments de réflexion

    Martin Pâquet

    1998-01-01

    Full Text Available "Histoire-carrefour", l'étudedel' État se glisse entre les césures des spécialités. Souventefois on adéploré, ál´instar du moderniste Richard Bonney, que "les zones de l'histoire qui ont été le plus négligées" soient "les zones-frontiéres' Dans un article récent, Jean-Marie Fecteau a renchéri dans le même  sens, soulignant la négligence de l'État et du Droit par l'historiographie contemporaine, malgré le renouveau de l'histoire politique.

  8. The thorium phosphate diphosphate as matrix for radioactive waste conditioning: radionuclide immobilization and behavior under irradiation; Le phosphate diphosphate de thorium, matrice pour le conditionnement des dechets radioactifs: immobilisation de radionucleides, comportement sous irradiation

    Pichot, Erwan [Inst. de Physique Nucleaire, Paris-11 Univ., 91 - Orsay (France)

    1999-04-13

    The aim of this work was to perform successively the decontamination of liquid solutions and the final immobilization of radionuclide storage using the same matrix. For this, thorium phosphate-diphosphate (TPD) of the formula Th{sub 4}P{sub 6}O{sub 23}, is proposed as a very resistant to water corrosion matrix. A new compound, thorium phosphate hydrogeno-phosphate (TPHP) of the formula Th{sub 2}(PO{sub 4}){sub 2}(HPO{sub 4}), nH{sub 2}O with n=3-7 was synthesized and characterized. Heated at 1100 deg.C it is transformed into the TDP. Ion exchange properties of TPHP were investigated. The exchange yields of imponderable caesium, strontium and americium ion onto TPHP (NaNO{sub 3} 0.1 M media at pH=6) are equal to 60% for the first one and 100% for the two others. The results interpreted in terms of ion-exchange led to determine selectivity coefficient values for each cation and suggested that only hydrated ions are exchanged. While the TPD is proposed for the high level nuclear waste storage, the irradiation effects, particularly structural modifications were studied using both {gamma} irradiation and charged particle irradiation. ESR and TL methods were carried out in order to identify radicals created during gamma radiation exposure. Correlation between ESR and TL experiments performed at room temperature clearly show three of PO{sub 3}{sup 2-} species and one POO{center_dot} species of free radicals. We have shown that Au-ion irradiation in the range of MeV energy involved TPD structure and chemical modifications. Important sputtering was interpreted in terms of local thermal chemical decomposition. We have shown, at room temperature, that the amorphization dose for heavy ion irradiation is between 0.1 to 0.4 dpa. (author) 146 refs., 46 figs., 21 tabs.

  9. Experience feedback examination in PWR type reactors operating for the 1997-1999 period; Examen du retour d'experience en exploitation des reacteurs a eau sous pression pour la periode 1997-1999

    NONE

    2004-07-01

    The present report is relative to the examination that the permanent group has made on the experience feedback in operation for PWR type reactors for the period 1997-1999 that was on eleven themes chosen by the Nuclear Safety and Radiation Protection Authority. It used analysis reports made by I.R.S.N. in support of four meetings of the permanent group devoted to this examination from April 2001 to June 2002. The different themes were operating uncertainties, machining to vibrations, analysis of incidents and gaseous releases, circuits, human factors, behaviour of electric batteries, risk of cold source loss. (N.C.)

  10. Les discussions reprennent chez Gate Gourmet CONFLIT. Les negociations pour une nouvelle CCT se derouleront sous l'égide de la Chambre genevoise des relations collectives de travail

    Mutter, F

    2003-01-01

    "Dialogue renoue chez Gate Gourmet a Geneve...cela serait la seconde fois seulement que la CRCT agirait de la sorte. L'unique precedent remonte a un different opposant le CERN à certains de ses employes" (1/2 page).

  11. Understanding and predicting the behaviour of silver base neutron absorbers under irradiations; Comprehension et prediction du comportement sous irradiation neutronique d`alliages absorbants a base d`argent

    Desgranges, C

    1998-12-31

    The effect of neutron irradiation induced transmutations on the swelling of AgInCd (AIC) alloys used as neutron absorber in the control rods of Pressurized Water Reactors has been studied both experimentally and theoretically. Effective atomic volumes have been determined in synthetic AgCdInSn alloys with various compositions and containing fcc and hc phases, representative of irradiated AIC (Sn is a transmutation product). Swelling is shown to result first from the transmutation of Ag into Cd and of In into Sn, both with larger effective volume than the mother atom, and second from grain boundaries precipitation of s still less dense hc phase when solid solubility of transmuted products is exceeded. For both fcc and hc phases, we have determined profiles at the temperatures in the vicinity of the operating temperature. Unusual characteristics of second phase growth at grain boundaries induced by transmutations are identified on a simple binary alloy model: kinetics is controlled by irradiation temperature which scales diffusivities and flux which scales transmutation rates, as well as by the grain size in the underlying matrix. To address the AgInCdSn alloys, a novel technique is proposed to model diffusion in multicomponent alloys. It is based on a linearization of a simple atomistic model. With a single set of parameters, for each phase, our model well reproduces our interdiffusion measurements in quaternary alloys as well as existing interdiffusion experiments in binary alloys. Finally this diffusion model implemented with a moving interface algorithm is used to model the growth of the second phase induced by transmutation in the AIC under irradiation. (authors) 74 refs.

  12. Sustainable development - billions of watts under the seas - Marine current turbines play simple - Technological waves; Developpement durable - Des milliards de watts sous les mers - Les hydroliennes jouent la simplicite - Vagues technologiques

    Lucas, Th.

    2011-10-27

    The author evokes the opportunities of power generation by the development of sea current or tidal stream turbines. Some developments are already tested by Norwegian, French, Danish, British and American companies. Some specific turbines are briefly presented. In order to reduce the cost of the electricity production from sea currents, manufacturers are using simple and robust technologies, and exploit the experience gained on wind turbines. Some designs and prototypes are evoked for the production of electricity by sea waves (Pelamis and Oyster projects). Principles, strengths and production projects are briefly indicated. The challenge of maintenance in sea environment is outlined for these projects

  13. Introduction to the reliability study of IGBT switching cells under strong constraints; Introduction a l'etude de la fiabilite des cellules de commutation a IGBT sous fortes contraintes

    Vallon, J.

    2003-12-15

    The reliability approach in power electronics is a complex problem including the coupling of current / voltage surges, physical and technological imperfections, from the die to the power circuit. First of all, we define a methodology based on the monitoring of a great number of components, during a long time campaign. Components are 600 V-50 A-20 kHz IGBT-diodes modules working in PWM inverter cells owing to an original opposition method. An exhaustive study of cell-switching failure modes allowed us to design a suitable and efficient protection. Afterwards, a complete reliability test bench was carried out with electrical and thermal monitoring. A preliminary screening protocol was also applied. The first results are presented in this thesis. (author)

  14. Study of alloy 600`S stress corrosion cracking mechanisms in high temperature water; Etude des mecanismes de corrosion sous contrainte de l`alliage 600 dans l`eau a haute temperature

    Rios, R

    1994-06-01

    In order to better understand the mechanisms involved in Alloy 600`s stress corrosion cracking in PWR environment, laboratory tests were performed. The influence of parameters pertinent to the mechanisms was studies : hydrogen and oxygen overpressures, local chemical composition, microstructure. The results show that neither hydrogen nor dissolution/oxidation, despite their respective roles in the process, are sufficient to account for experimental facts. SEM observation of micro-cleavage facets on specimens` fracture surfaces leads to pay attention to a new mechanism of corrosion/plasticity interactions. (author). 113 refs., 73 figs., 15 tabs., 4 annexes.

  15. Gestion des bio-agresseurs et réduction des pesticides en culture de laitue sous abris froids : apports croisés d’expérimentations factorielles et systémiques

    Barrière , Virginie

    2015-01-01

    The reduction of pesticide reliance in lettuce cropping systems is a short term objective sharedby public authorities and by the stakeholders of lettuce market. Reaching this goal implies thesubstitution of pesticides by others techniques which may limit pest and pathogen damage. Thesetechniques can be intended to mitigate pest and pathogen invasion or propagation, to increaseplant defenses or to remove pests and pathogens from the crop. The improvement of currentcropping systems relies on i)...

  16. Développement urbain fractal sous contraintes d'accessibilités - Modèles et outils d'aide à la décision pour l'aménagement urbain

    Frankhauser , Pierre; Tannier , Cécile; Houot , Hélène; Vuidel , Gilles

    2010-01-01

    77; Ce projet fait suite à une recherche financée par le PREDIT intitulée " Vers des déplacements périurbains plus durables - Proposition de modèles fractals opérationnels d'urbanisation " (Dir. P. Frankhauser - Participants : H. Houot, C. Tannier et G. Vuidel)1. Ce premier projet, réalisé entre juillet 2005 et juin 2007, a posé les bases du présent projet, à savoir la définition de ses fondements conceptuels et de ses principes méthodologiques. Le présent projet a pour but de compléter la mé...

  17. La violence politique au prisme du genre à travers la presse française (1970-1994, thèse de doctorat en histoire contemporaine sous la direction de Christine Bard, Université d'Angers, 2011

    Fanny Bugnon

    2012-05-01

    Full Text Available Située à la croisée deux thématiques – l'histoire des femmes et l'histoire de la violence – cette thèse s'inscrit dans la dynamique relativement récente de l'histoire de la violence des femmes en France. Double « silence de l'histoire », la violence des femmes est ici envisagée dans sa dimension politique à partir de sa médiatisation, interrogeant ainsi un double phénomène propre aux démocraties occidentales : la résurgence, dans l'après-68, d'actes violents et organisés motivés par des raiso...

  18. Modification of non metallic materials under the influence of the radiation and thermal retrogradation of these modifications; Modification de materiaux non metalliques sous l'influence des rayonnements et retrogradation thermique de ces modifications

    Mayer, G; Perio, P; Gigon, J; Tournarie, M [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1955-07-01

    The action of the radiation on solids constitute an extremely vast domain of study, which the CEA hardly begins. There is not a very long time, indeed, that we have relatively intense fluxes (6.10{sup 12} thermal neutrons by cm{sup 2}.s{sup -} {sup 1} in the center of the reactor core of Saclay). Materials submitted to radiations, were followed by the evolution of a certain number of physical properties. The study of thermal retrogradation, at moderate temperature, of the modifications provoked by the irradiation were also followed. We will limit, in this report, to expose our experiences on graphite and lithium fluoride. (M.B.) [French] L'action des rayonnements sur les solides constitue un domaine extremement vaste dont l'etude, au Commissariat a l'Energie Atomique, commence a peine. Il n'y a pas tres longtemps, en effet, que nous disposons de flux relativement intenses (6.10{sup 12} neutrons thermiques par cm{sup 2}.s{sup -1} au centre de la pile de Saclay). Dans les materiaux soumis au rayonnement nous suivons l'evolution d'un certain nombre de proprietes physiques et nous etudions la retrogradation thermique, a temperature moderee, des modifications provoquees par l'irradiation. Nous nous bornerons ici a exposer nos experiences sur le graphite et le fluorure de lithium. (M.B.)

  19. Electrochemical measurements of mass transfer in RTILs (Room Temperature Ionic Liquids) medium under low frequency ultrasound irradiation; Mesures electrochimiques de transfert de matiere en milieu RTIL's (Room Temperature Ionic Liquids) sous irradiation ultrasonore basse frequence

    Costa, C.; Hihn, J.Y.; Rebetez, M.; Doche, M.L. [Universite de Franche Comte - IUT Dept. Chimie, Institut UTINAM-UMR CNRS 6213, 25 - Montbeliard (France); Costa, C.; Bisel, I. [CEA Valrho, Dir. de l' Energie Nucleaire (DEN/DRCP/SCPS/LPCP), 30 - Marcoule (France); Moisy, Ph. [CEA Valrho, Dir. de l' Energie Nucleaire (DEN/DRCP/SCPS/LCA), 30 - Marcoule (France)

    2007-07-01

    The aim of this work is to measure the influence of ultrasounds on the mass transfer at the electrode. The electro diffusional method which consists to measure the limit diffusion current on the polarization curve i=f(E) of a reversible couple in diluted solution in the electrolyte. The used couple changes with the electrolytic medium: potassium ferro/ferricyanide in water, ferrocene/ferricinium for acetonitrile and for the ionic liquid 1-butyl-3-methyl-imidazolium bis(tri-fluoro-methyl-sulfonyl)imide [BuMIm][CF{sub 3}SO{sub 2}){sub 2}N]). The limit diffusion currents are converted into mass transfer coefficients and then into a dimensional Sherwood numbers to allow an easier comparison of the results between the different research teams participating to this study. Recent tests, carried out in partner laboratories (LCMI-UFC, LPCP-CEA and LCA-CEA) have demonstrated the interest of the use of power ultrasounds in Room Temperature Ionic Liquids (RTILs) but revealed too a lot of experimental difficulties. Nevertheless, it appears that the ultrasounds are an aging mode particularly adapted to the RTILs because the mass transfer to the electrode is there 5 times more efficient than in presence of an electrode turning at 4500 tr.min{sup -1}, while limiting their re-hydration. (O.M.)

  20. Observation and simulation of non-laminar flow phenomena at the HDR site near Soulth-sous-forets; Beobachtung und Simulation von nicht-laminarem Fliessverhalten am HDR-Standort Soultz

    Kohl, T [ETH Hoenggerberg, Zuerich (Switzerland). Inst. fuer Geophysik; Evans, K F; Hopkirk, R J [Polydynamics Engineering, Maennedorf (Switzerland); Jung, R [Bundesanstalt fuer Geowissenschaften und Rohstoffe, Hannover (Germany); Rybach, L [ETH Hoenggerberg, Zuerich (Switzerland). Inst. fuer Geophysik und Radiometrie

    1997-12-01

    Three independent multi-rate flow experiments were conducted in 1994 and 1995 in the open hole depth interval of a wellbore at the Hot-Dry-Rocks (HDR) test site Soultz. The steady state and transient dowmhole pressure records gave clear indications of non-Darcian flow. A numerical model has been set-up to evaluate these two measurements. An excellent fit of the transient pressure responses of all three flow tests could be achieved by assuming a simple model geometry. The models predict fluid transport along a conduit with substantial surface area in which fully-turbulent flow is occurring. The parameters required by our best-fit simulation all fall into a physically reasonable range. Sensitivity analysis demonstrates a non-Darcian flow regime along highly conductive features. The existence of high capacity far-field faults as postulated in our model confirms earlier characterisations of the Soultz test site. (orig.) [Deutsch] In den Jahren 1994 und 1995 wurden drei unabhaengige Druck- bzw. Fliessratentests in den Bohrungen GPK1 und GPK2 des HDR Standortes Soultz durchgefuehrt. Sowohl die stationaeren wie auch die instationaeren Druckaufzeichnungen gaben bereits klare Hinweise auf nichtlaminare, turbulent-aehnliche Stroemungsverhaeltnisse. Zur genaueren Interpretation dieser Daten wurde das numerische Programm FRACTure erweitert. Unter der Annahme eines geometrisch einfachen Modells konnten die instationaeren Druckantworten sehr gut angepasst werden. Es gelang sogar, die beiden in GPK1 durchgefuehrten Tests durch dieselben Modelle zu erklaeren. Die hierfuer benoetigten Modellparameter liegen in einem physikalisch sinnvollem Rahmen und bestaetigen z.T. fruehere Untersuchungen. Die Existenz grosser Stoerungszonen, welche von den Modellen vorausgesetzt werden, bestaetigt ebenfalls fruehere Charakterisierungen des HDR Standortes Soultz als ein teilweise offenes hydraulisches System. (orig.)

  1. Study of the damaging mechanisms of a copper / carbon - carbon composite under thermomechanical loading; Etude des mecanismes d'endommagement d'un assemblage cuivre / composite carbone - carbone sous chargement thermomecanique

    Moncel, L

    1999-06-18

    The purpose of this work is to understand and to identify the damaging mechanisms of Carbon-Carbon composite bonded to copper under thermomechanical loading. The study of the composite allowed the development of non-linear models. These ones have been introduced in the finite elements analysis code named CASTEM2000. They have been validated according to a correlation between simulation and mechanical tests on multi-material samples. These tests have also permitted us to better understand the behaviour of the bonding between composite and copper (damaging and fracture modes for different temperatures) under shear and tensile loadings. The damaging mechanisms of the bond under thermomechanical loading have been studied and identified according to microscopic observations on mock-ups which have sustained thermal cycling tests: some cracks appear in the composite, near the bond between the composite and the copper. The correlation between numerical and experimental results have been improved because of the reliability of the composite modelization, the use of residual stresses and the results of the bond mechanical characterization. (author)

  2. Study of the damaging mechanisms of a carbon - carbon composite bonded to copper under thermomechanical loading; Etude des mecanismes d'endommagement d'un assemblage cuivre / composite carbone - carbone sous chargement thermomecanique

    Moncel, L

    1999-06-15

    The purpose of this work is to understand and to identify the damaging mechanisms of Carbon-Carbon composite bonded to copper under thermomechanical loading. The study of the composite allowed the development of non-linear models. These ones have been introduced in the finite elements analysis code named CASTEM 2000. They have been validated according to a correlation between simulation and mechanical tests on multi-material samples. These tests have also permitted us to better understand the behaviour of the bonding between composite and copper (damaging and fracture modes for different temperatures) under shear and tensile loadings. The damaging mechanisms of the bond under thermomechanical loading have been studied and identified according to microscopic observations on mock-ups which have sustained thermal cycling tests: some cracks appear in the composite, near the bond between the composite and the copper. The correlation between numerical and experimental results have been improved because of the reliability of the composite modelization, the use of residual stresses and the results of the bond mechanical characterisation. (author)

  3. Analyse of the potential of the high temperature reactor with respect to the use of fissile materials; Analyse des capacites des reacteurs a haute temperature sous l'aspect de l'utilisation des matieres fissiles

    Damian, F

    2001-07-01

    The high temperature reactors fuel is made of micro-particles dispersed in a graphite matrix. This configuration makes it possible to reach high burnup, higher than 700 GWj/t. Thanks to the decoupling between the thermal and the neutronic behaviors in the core many types of fuels can be used. These characteristics give to HTR reactor very good capacities to burn fissile materials. This work was done in the frame of the evaluation of HTR capacities to enhance the value of the plutonium stocks. These stocks are currently composed of the irradiated fuels discharged from classical PWR or the dismantling of the nuclear weapons and represent a significant energy potential. These studies concluded that high cycles length can be reached whatever the plutonium quality is (from 50 % to 94 % of fissile plutonium). In addition, it was demonstrated that the moderator temperature coefficient becomes locally positive for highly burn fuel while the core global moderator temperature coefficient remained negative in the operation range of the reactor. A significant share of this work was first devoted to the setting of a modeling of the fuel element but also of the reactor's core with the codes of system SAPHYR. The whole of modeling was validated by reference calculations. This work of code assessment is justified by a preliminary work that showed that the classical calculation scheme used for PWR could not be transposed directly to HTR core. (author)

  4. Study of vibrations and stabilization of linear collider final doublets at the sub-nanometer scale; Etude des vibrations et de la stabilisation a l'echelle sous-nanometrique des doublets finaux d'un collisionneur lineaire

    Bolzon, B

    2007-11-15

    CLIC is one of the current projects of high energy linear colliders. Vertical beam sizes of 0.7 nm at the time of the collision and fast ground motion of a few nanometers impose an active stabilization of the final doublets at a fifth of nanometer above 4 Hz. The majority of my work concerned vibrations and active stabilization study of cantilever and slim beams in order to be representative of the final doublets of CLIC. In a first part, measured performances of different types of vibration sensors associated to an appropriate instrumentation showed that accurate measurements of ground motion are possible from 0.1 Hz up to 2000 Hz on a quiet site. Also, electrochemical sensors answering a priori the specifications of CLIC can be incorporated in the active stabilization at a fifth of nanometer. In a second part, an experimental and numerical study of beam vibrations enabled to validate the efficiency of the numerical prediction incorporated then in the simulation of the active stabilization. Also, a study of the impact of ground motion and of acoustic noise on beam vibrations showed that an active stabilization is necessary at least up to 1000 Hz. In a third part, results on the active stabilization of a beam at its two first resonances are shown down to amplitudes of a tenth of nanometer above 4 Hz by using in parallel a commercial system performing passive and active stabilization of the clamping. The last part is related to a study of a support for the final doublets of a linear collider prototype in phase of finalization, the ATF2 prototype. This work showed that relative motion between this support and the ground is below imposed tolerances (6 nm above 0.1 Hz) with appropriate boundary conditions. (author)

  5. A multi-agent design for a pressurized water reactor (P.W.R.) control system; Modelisation multi-agents pour la conduite d'un reacteur a eau sous pression (REP)

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

    1999-01-01

    This PhD work is in keeping with the complex industrial process control. The starting point is the analysis of control principles in a Pressurized Water Reactor (P.W.R). In order to cope with the limits of the present control procedures, a new control organisation by objectives and means is defined. This functional organisation is based on the state approach and is characterized by the parallel management of control functions to ensure the continuous control of the installation essential variables. With regard to this complex system problematic, we search the most adapted computer modeling. We show that a multi-agent system approach brings an interesting answer to manage the distribution and parallelism of control decisions and tasks. We present a synthetic study of multi-agent systems and their application fields.The choice of a multi-agent approach proceeds with the design of an agent model. This model gains experiences from other applications. This model is implemented in a computer environment which combines the mechanisms of an object language with Prolog. We propose in this frame a multi-agent modeling of the control system where each function is represented by an agent. The agents are structured in a hierarchical organisation and deal with different abstraction levers of the problem. Following a prototype process, the validation is realized by an implementation and by a coupling to a reactor simulator. The essential contributions of an agent approach turn on the mastery of the system complexity, the openness, the robustness and the potentialities of human-machine cooperation. (author)

  6. Les illégalismes sexuels féminins sous le regard de la justice correctionnelle à Toulouse (1826-1886. Master 2 d’histoire contemporaine, Université Toulouse II-Le Mirail, (dir. Sylvie Chaperon, 2010

    Julie Auger

    2011-10-01

    Full Text Available Qu’ils relèvent d’une sexualité adultérine, incestueuse, vénale ou tout simplement visible voire audible, les illégalismes sexuels féminins jugés au tribunal correctionnel sont très divers et sont tous moralement réprouvés si ce n’est pénalement réprimés. Pourtant, le poids de la sexualité dans les jugements des magistrats n’est pas évident. Théoriquement, ce n’est pas la sexualité en tant que telle que l’on réprime mais les conditions de son expression. La sexualité féminine considérée comme...

  7. Spatial and temporal distribution of long term public policy costs under uncertainty, the case of climate change; Distribution spatiale et temporelle des couts de politiques publiques sous incertitudes: theorie et pratique dans le cas de l'effet de serre

    Lecocq, F

    2000-07-15

    Because of the inertia of the climate system, policy makers cannot avoid making early decisions regarding climate change in a sea of uncertainties. In this context, the very legitimacy of economic analysis to tackle such questions, and in particular the underlying equity issues (who pays for climate mitigation? when?) faces widespread skepticism. This thesis aims at demonstrating how public economy still remains a powerful tool to try and put some rationale into the debate, by checking the internal consistency of the different discourses, and by providing robust insights, if not definitive answers, into climate decisions. We use a set of compact integrated climate policy optimization models to progressively introduce, articulate, and assess numerically the prominent issues at stake. We obtain three main results. We first demonstrate that the so-called timing debate between short term and long term action cannot be reduced to a mere dispute over discount rate. Given the high uncertainties surrounding climate change indeed, the margins of freedom we pass on to future generations, and in particular the technical and institutional systems we transmit, become more important than the discount rate value. Secondly, we apply the various emission quota allocation rules proposed in the literature for the enlargement of annex B to developing economies. We show that the distributive outcome of these rules depends critically on ex ante assumptions about future economic and emission growth. Therefrom, we conclude that a careful design of the institutions surrounding the tradable permits market is a necessary condition to enhance the systems robustness. Last, on a broader perspective, this thesis illustrates the complementarity between ethics and economics: though the economist does not have per se a superior word about what is fair, his toolbox is powerful enough to show how some intuitively appealing ideas, such as a zero discount rate to take care of both present and future generations alike, or a per capita emission quota allocation, may lead to very questionable consequences. (author)

  8. Situation de la cercosporiose noire des bananiers et plantains Musa spp. sous différents systèmes de culture à Yangambi, Haut-Zaïre

    Mobambo, KN.

    1993-01-01

    Full Text Available Black sigatoka situation of bananas and plantains Musa spp. under different farming systems at Yangambi, Upper-Zaire. Black sigatoka, a leaf spot disease, caused by Mycosphaerella fijiensis Morelet seems to be one of the major constraints in the banana and plantain production in Upper-Zaire. Indeed, a survey study undertaken at Yangambi on 12 plantain and 4 banana cultivars revealed that all the observed cultivars were attacked with an exception of banana "Yangambikm 5" which was tolerant. In otherhand, significant differences were observed between bananas and plantains cultivated in fields and those planted in backyards. The regular application of organic matter in backyard farms seems to be one of the major reasons of those differences.

  9. Analyse comparative de pratiques d’animation d’une discussion à visée démocratique et philosophique vues sous l’angle de la temporalité

    Pierrisnard, Christine

    2015-01-01

    Cette étude s’intéresse à la manière dont l’outil « Discussion à Visée Démocratique et Philosophique » (DVDP) est transformé par ses utilisateurs en instrument au fil des situations. L’analyse comparative des pratiques d’un animateur plutôt novice et d’un animateur expert fait apparaître trois éléments cruciaux de représentation temporelle de la situation de DVDP. Un empan temporel large, ancré dans le temps long pour le nécessaire recul de la pensée ; le kaïros, ancré dans l’immédiateté et l...

  10. La culture juridique des clercs dans le Royaume de Hongrie sous les rois angevins au XIVe siècle - Judical Culture of Clerics in the Medieval Hungarian Kingdom under the Angevin Kings (14th Century

    KISS, Gergely

    2015-07-01

    Full Text Available Th e present work aims to show the main elements of the legal culture of the clergy in the 14th century-Hungary. Th e starting point is the explanation of the notion “legal culture”, the presentation of its three main elements, the legal service at the royal court, the activities of the loca credibilia and of the ecclesiastical courts, the personal legal culture. Th e paper shows not only the connection of the legal culture and the development of the bureaucratic writing, the chancellery, but the eff ects of the university studies as well, its main turning points and periods (Paris, Bologna, Padova, with a special focus on the Angevin era (14th century. We can state that the legal culture of Hungarian clergy underwent several changes in this era. With the laicisation of the bureaucratic activities, the royal court needed representatives who had legal experiences for its international aff airs, thus it favoured the change of the legal culture of the clergy at the court. Th e same period is also very important because of the ecclesiastical and secular justice. Several elements of personal legal culture (e. g. collection are also presented.

  11. Towards a quantification of stress corrosion mechanisms: numerical simulations of hydrogen-dislocations at the very crack tip; Vers une quantification des mecanismes de corrosion sous contrainte: simulations numeriques des interactions hydrogene-dislocations en pointe de fissure

    Chateau, J.P

    1999-01-05

    We discuss the respective roles played by anodic dissolution and hydrogen in SCC mechanisms of f.c.c. materials, by studying the fracture of copper in nitrite for which we compare the results with that previously obtained in 316L steel in hot chloride. It is surprising to note that even the crystallographies at the scale of the micron are different, the macroscopic inclination of the fracture surfaces are the same. In the case of 316L steel, the formation of strong pile-ups in the presence of hydrogen leads to a zigzag fracture along alternated slip planes in the most general case. In the absence of hydrogen, as in copper, this mechanism effectively disappears. Furthermore, numerical simulations of crack shielding by dislocations emitted on one plane predict the macroscopic inclination. It shows that it is due to the mere dissolution which confines slip activity at the very crack tip in f.c.c. materials. In order to quantify the mechanism involved in 316L steel, we developed simulations which numerically solve the coupled diffusion and elasticity equations for hydrogen in the presence of a crack and shielding dislocations. They reproduce the mechanisms of hydrogen segregation on edge dislocations and of a localised softening effect by decreasing pair interactions. These mechanisms lead to i) a localisation of hydrogen embrittlement along the activated slip planes, ii) an increase of the dislocation density in pile-ups, and iii) a decrease of the cross slip probability. These three factors enhance micro-fracture at the head of a pile-up, which is responsible of thezigzag fracture. Introducing the free surface effects for hydrogen, we point out a new mechanism: the inhibition of dislocation sources at the crack tip, which is relevant with the brittle fracture surfaces observed in some cases in 316L steel. The quantification of these different mechanisms allows to give a relation between the local fracture possibility and the macroscopic parameters. A general law for softening is proposed, and we show that micro-fracture occurs for realistic values of three key parameters: hydrogen concentration, decrease of k{sub lc} and obstacle resistance. (author)

  12. Two-phase flows during draining of liquefied gases initially undersaturated. Validation by water and CFC11; Ecoulements diphasiques lors de la vidange de gaz liquifies initialement sous satures. Validation par l`eau et le CFC11

    May, L.

    1996-12-11

    In petroleum industry, the safety studies require to estimate the two-phase flow during accidental draining of pressurized liquefied gas storages. Meanwhile the mass flow strongly depends of initial conditions. Then it is primordial to be able to reckon it in the case where it is the highest, that is to say when the fluid is initially undersaturated. An experimental installation has been carried out. The used fluids are water and CFC11. The experimental measures show that the thermodynamic conditions at the inlet of the pipe (P at +/- 15 mbar and T at +/- 0.15 degrees Celsius) are well controlled. The measured mass flows are compared to different models. The frictions in the monophase domain have been taken into account. It has been shown that the extensive H.E.M. model perfectly estimates the mass flow (as well as for water than for CFC11) for large deviations to saturation. In order to correctly predict the domain of weak variation to saturation, D.E.M. (out of equilibrium) models or H.R.M. (homogeneous model of relaxation) models have to be used. (O.M.) 50 refs.

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

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

    1967-07-01

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

  14. High fetal irradiation: about one pregnant woman receiving infra diaphragmatic radiotherapy for Hodgkin lymphoma; Irradiation foetale elevee: a propos d'une femme dont la grossesse etait meconnue irradiee en sous-diaphragmatique pour un lymphome hodgkinien

    Moreau, M.V.; Brunaud, C.; Marchesi, V.; Hoffstetter, S.; Peiffert, D. [Centre Alexis-Vautrin, Service de Radiotherapie, 54 - Vandoeuvre-les-Nancy (France); Bologna, S. [Centre Hospitalier Universitaire Nancy-Brabois, Service d' Hematologie, 54 - Vandoeuvre-les-Nancy (France)

    2007-12-15

    We report the case of a 19-year-old young woman for whom was discovered a pregnancy at the end of the irradiation for a Hodgkin lymphoma (stage IV bone Bb), initially treated by chemotherapy. The radiotherapy delivered 36 Gy in infra-diaphragmatic volumes (lumbo-aortic, spleen, L5), beginning in a pregnant patient for less than 4 amenorrhea weeks. The calculated received fetal dose (literature data, measurement with software T.P.S., measurement on phantom) is high: it's between 2.8 and 5 Gy. With a current follow-up of 4 years since the radiotherapy's end, the patient is in complete remission and her child presents with a normal development for the age, in spite of the infra diaphragmatic irradiation. (authors)

  15. Etude et simulation du protocole TTEthernet sur un sous-systeme de gestion de vols et adaptation de la planification des tâches a des fins de simulation

    Abidi, Dhafer

    TTEthernet is a deterministic network technology that makes enhancements to Layer 2 Quality-of-Service (QoS) for Ethernet. The components that implement its services enrich the Ethernet functionality with distributed fault-tolerant synchronization, robust temporal partitioning bandwidth and synchronous communication with fixed latency and low jitter. TTEthernet services can facilitate the design of scalable, robust, less complex distributed systems and architectures tolerant to faults. Simulation is nowadays an essential step in critical systems design process and represents a valuable support for validation and performance evaluation. CoRE4INET is a project bringing together all TTEthernet simulation models currently available. It is based on the extension of models of OMNeT ++ INET framework. Our objective is to study and simulate the TTEthernet protocol on a flight management subsystem (FMS). The idea is to use CoRE4INET to design the simulation model of the target system. The problem is that CoRE4INET does not offer a task scheduling tool for TTEthernet network. To overcome this problem we propose an adaptation for simulation purposes of a task scheduling approach based on formal specification of network constraints. The use of Yices solver allowed the translation of the formal specification into an executable program to generate the desired transmission plan. A case study allowed us at the end to assess the impact of the arrangement of Time-Triggered frames offsets on the performance of each type of the system traffic.

  16. Radiation Treatment of Meat Products and Animal By-Products; Traitement par Rayonnements des Viandes et Derives et des Sous-Produits Animaux; Radiatsionnaya obrabotka myasnykh produktov i subproduktov zhivotnogo proiskhozhdeniya; Irradiacion de la Carne y sus Derivados

    Hansen, P. -I.E. [Danish Meat Research Institute, Roskilde (Denmark)

    1966-11-15

    Application of radiation in food technology can only be considered as an alternative to existing preservation methods when a higher quality product and/or a cheaper product will result, or in cases where no alternative methods exist. With this view in mind, work performed at the Danish Meat Research Institute on sliced bacon, canned hams, luncheon meat, and animal feeding stuffs, i.e. meat and bone meal and blood meal, is reviewed and discussed. The conclusion drawn from the experimental results is that the formation of off-flavours in irradiated meat products is a very serious problem and the most important obstacle to a successful application of irradiation in meat processing. It is, therefore, essential that future research should concentrate on finding means to reduce the irradiation flavour. A number of approaches to solve this problem are mentioned and the Danish work in this field which has been centred mainly on the use of very high dose-rates and of non-equal dose distribution in cans is reviewed, and the concepts briefly described. (author) [French] L'application des rayonnements dans l'industrie alimentaire ne saurait etre consideree en remplacement des methodes de conservation actuelles que s'il en resulte un produit de qualite superieure ou un produit meilleur marche, ou encore lorsqu'on ne peut utiliser aucune methode de rechange. Dans cet esprit, l'auteur examine et commente les travaux accomplis par l'Institut danois de recherches sur la viande concernant le lard en tranches, le jambon en conserve, les pates de viande en conserve (luncheon meat) et les aliments pour animaux, c'est-a-dire les farines de viande et d'os et la farine de sang. Il conclut des resultats experimentaux que la formation de gouts indesirables dans les viandes irradiees pose un probleme tres serieux et constitue l'obstacle le plus important au succes de l'application des rayonnements a la preparation des viandes. Il importe donc que les futures recherches portent avant tout sur la determination des moyens permettant d'eliminer le gout du a l'irradiation. Le memoire signale un certain nombre de methodes destinees a resoudre ce probleme. Il passe en revue les travaux accomplis en la matiere au Danemark, lesquels ont porte principalement sur le recours a des taux de dose tres eleves et sur la distribution inegale des doses dans les boites de conserve, et decrit brievement les divers principes en jeu. (author) [Spanish] En la tecnologia de los alimentos, el empleo de las radiaciones en lugar de los actuales metodos de conservacion solo puede considerarse cuando permite obtener productos de mejor calidad o mas baratos o cuando no existe ningun otro metodo utilizable. Teniendo esto presente, en la memoria se examina la labor que en el Instituto Danes de Investigaciones sobre la Carne se ha realizado con tocino en lonchas, jamon enlatado, pastel de carne en lata y alimentos para los animales, es decir, harina de carne y huesos, y harina de sangre. De los resultados de los experimentos se desprende que la aparicion de mal sabor en los productos carnicos irradiados es un problema muy grave y el obstaculo mas importante que se opone a la irradiacion de la' carne durante su tratamiento. Por tanto, es esencial que en lo sucesivo las investigaciones se concentren en la manera de evitar la alteracion del sabor provocada por la irradiacion. En la memoria se mencionan varios metodos para resolver este problema y se informa sobre la labor llevada a cabo en Dinamarca que ha consistido principalmente en exponer latas de conserva a intensidades muy elevadas con una distribucion desigual de las dosis. Por ultimo, se examinan algunos aspectos teoricos. (author) [Russian] Primenenie izluchenij v tehnologii pishhevyh produktov mozhet rassmatrivat'sja tol'ko kak al'ternativa k sushhestvujushhim metodam sohranenija produktov pitanija, esli neobhodimo poluchit' produkt bolee vysokogo kachestva i/ili bolee deshevyj ili v teh sluchajah, kogda ne sushhestvuet al'ternativnyh metodov. S jetoj cel'ju v Datskom nauchno-issledovatel'skom institute mjasnoj promyshlennosti provodilis' raboty s bekonom, konservirovannoj vetchinoj, mjasnymi konservami i zhivotnymi kormami, kak-to: mjasnaja, kostnaja i krovjanaja muka. Daetsja obzor i obsuzhdenie jetih rabot. Vyvod, sdelannyj v rezul'tate provedennyh opytov, zakljuchaetsja v tom, chto obrazovanie neprijatnyh privkusov v obluchennyh produktah predstavljaet soboj ves'ma ser'eznuju problemu i predstavljaet znachitel'nuju trudnost' na puti k uspeshnomu primeneniju obluchenij v obrabotke mjasa. Pojetomu vazhno, chtoby pri provedenii posledujushhih issledovanij glavnoe vnimanie obrashhalos' na izyskanie sredstv dlja umen'shenija privkusov v rezul'tate obluchenija. Upominaetsja rjad podhodov k razresheniju jetoj problemy, i daetsja obzor rabot, provedennyh v jetoj oblasti Datskim institutom, kotorye, glavnym obrazom, byli skoncentrirovany na ispol'zovanii ochen' moshhnyh doz i neravnogo raspredelenija dozy v konservah. Daetsja kratkoe opisanie sushhestvujushhih koncepcij. (author)

  17. Search for time reversal violation in neutron decay; Recherche d'une violation de l'invariance sous le renversement du temps dans la desintegration du neutron

    Gorel, P

    2006-06-15

    The topic of this thesis is the implementation of an experimental setup designed to measure the R- and N-parameters in polarized neutron decay, together with the data analysis. Four observables are necessary for this measurement: the neutron polarization, the electron momentum and both transverse components of the electron polarization. These last two are measured using a Mott polarimeter. The other observables are determined using the same detectors. The precision to be reached on the R-parameter is 0.5%. A non zero value would sign a time reversal invariance violation and therefore would be a hint of physics beyond the Standard Model. This document presents the work done to prepare and optimize the experimental setup before the data acquisition run performed in 2004. Particular care was taken on the scintillator walls, used to trigger the acquisition and measure the electron energy. The second part concerns the implementation of methods to extract R and N from the data, and the study of the background recorded simultaneously. (author)

  18. Mémoires sous vitrines : mises en scènes de l’esclavage dans les musées du Bénin et du Ghana

    Seiderer, Anna

    2009-01-01

    L’article porte sur les stratégies élaborées par trois nations fortement, mais à titres différents, impliquées dans la traite de l’esclavage. Il s’agit de la France, du Bénin et du Ghana. L’objectif est de débusquer les éléments idéologiques inhérents à la construction de la mémoire à travers les vitrines érigées par ces trois nations. Nous nous livrons dans un premier temps à un décryptage des allocutions présidentielles afin d’expliciter les limites de la reconnaissance de la traite de l’es...

  19. Optimization by simulation of the coupling between a sub-critical reactor and its spallation source. Towards a pilot reactor; Optimisation par simulation du couplage entre un reacteur sous-critique et sa source de spallation. Application a un demonstrateur

    Kerdraon, D

    2001-10-01

    Accelerator Driven Systems (ADS), based on a proton accelerator and a sub-critical core coupled with a spallation target, offer advantages in order to reduce the nuclear waste radiotoxicity before repository closure. Many studies carried out on the ADS should lead to the definition of an experimental plan which would federate the different works in progress. This thesis deals with the neutronic Monte Carlo simulations with the MCNPX code to optimize such a system in view of a pilot reactor building. First, we have recalled the main neutronic properties of an hybrid reactor. The concept of gas-cooled eXperimental Accelerator Driven System (XADS) chosen for our investigations comes from the preliminary studies done by the Framatome company. In order to transmute minor actinides, we have considered the time evolution of the main fuels which could be reasonably used for the demonstration phases. The neutronic parameters of the reactor, concerning minor actinide transmutation, are reported. Also, we have calculated the characteristic times and the transmutation rates in the case of {sup 99}Tc and {sup 129}I isotopes. We have identified some neutronic differences between an experimental and a power ADS according to the infinite multiplication coefficient, the shape factor and the level of flux to extend the demonstrator concept. We have proposed geometric solutions to keep the radial shape factor of a power ADS acceptable. In the last part, beyond the experimental XADS scope, we have examined the possible transition towards an uranium/thorium cycle based on Molten Salt Reactors using a power ADS in order to generate the required {sup 233}U proportion. (author)

  20. Study of the effect of {sup 11}Be halo on the sub-coulombian fusion; Etude de l`effet du halo du {sup 11}Be sur la fusion sous-coulombienne

    Felou Youmbi, V

    1996-12-11

    Fission cross sections of {sup 9,11}Be + {sup 238}U systems are measured in the energy range of the coulomb barrier. These measures allow the study of neutron halo effect on sub coulombian fusion. {sup 9,11}Be beams are obtained by fragmentation at the GANIL facilities. The fusion between incident particle and the target nucleus leads to a compound nucleus which disappears by fission. The FUSION detector is used to detect the fission fragments by coincidence. We present some calculations of potential barriers by using Wong formula. The nucleus-nucleus interaction is simulated by a double convolution between the nucleus density and the effective M3Y interaction. In a more realistic framework ECIS94 code calculates the fusion cross section by using a coupling formalism. Theoretical values and experimental results are compared. We get a good agreement for {sup 9}Be + {sup 238}U system and an unusual behaviour appears for {sup 11}Be + {sup 238}U system 116 refs.

  1. Le cône sous-marin du Nil et son réseau de chenaux profonds : nouveaux résultats (campagne Fanil)The Nile Cone and its channel system: new results after the Fanil cruise

    Bellaiche, Gilbert; Loncke, Lies; Gaullier, Virginie; Mascle, Jean; Courp, Thierry; Moreau, Alain; Radan, Silviu; Sardou, Olivier

    2001-10-01

    The meandrous leveed channels of the Nile Cone show clear evidence of avulsions. Their sedimentary architecture is founded on numerous stacked lens-shaped acoustic units. In the areas of the distal fan, lobe deposits are apparent from multichannel imagery. Huge debris flow deposits, sometimes associated with pockmarks, are recognized. Mud volcanoes and gas seeping are closely associated with faulting. In the East, a very long north-trending channel, originating from the Egyptian coast, merges with a network of channels, very probably originating from the Levantine coasts. Both networks outlet in the sedimentary basin located south of Cyprus.

  2. Subcontracting relations and their effects on safety and security in two firms: SNCF and GrDF; Les relations de sous-traitance et leurs effets sur la surete et la securite dans deux entreprises: SNCF et GrDF

    Ponnet, Marie

    2011-07-04

    Because of economical processes that tend to move the frontiers of firms salaried relations of uncertain status are found coexisting inside the very same working world. From a qualitative investigation mixing employees' interviews and observations made on SNCF and GrDF working sites our research offers to think about the relations linking subcontracting, maintenance, safety and security. Considering subcontracting as a particular way for professional bodies to be associated allows us to wonder about its effects within a same firm (the 'integrated' subcontracting) as much as between a principal and a provider. Our thesis shows that when change occurs inside the organization - like the creation of new committees of experts or the reorganizing of an old service - security and safety can be impacted because thus professional bodies tend to be reconfigured while modifications affect practices, professional identities and work division. The relations between subcontractors and principal are complicated and their consequences depend from the context they are placed in, determined by a combination of various characteristics such as the confidence level, the available time, the reputation, the position occupied by the subcontractor. Our investigation makes clear that there is no direct link between subcontracting, security and safety. Their effects, in spite of their reality, are submitted to the altering mediation of legal factors (related to economic national and European issues) and concern the working organization as well as the professional identities. (author)

  3. Source mechanisms of micro-earthquakes induced in a fluid injection experiment at the HDR site Soultz-sous-Forêts (Alsace) in 2003 and their temporal and spatial variations

    Horálek, Josef; Jechumtálová, Zuzana; Dorbath, L.; Šílený, Jan

    2010-01-01

    Roč. 181, č. 3 (2010), s. 1547-1565 ISSN 0956-540X R&D Projects: GA AV ČR IAA300120911; GA ČR GA205/09/0724 Grant - others:EU(XE) MTKI-CT-2004-517242 Institutional research plan: CEZ:AV0Z30120515 Keywords : downhole methods * hydrogeophysics * controlled source seismology * earthquake source observations * fracture and flow Subject RIV: DC - Siesmology, Volcanology, Earth Structure Impact factor: 2.411, year: 2010

  4. L'internat affectif ou Dans quelle mesure et sous quelles conditions l'éducateur d'internat au Centre Oriph doit-il et peut-il répondre aux besoins affectifs des adolescents?

    Petrig, Michael; Grau, Christiane

    2006-01-01

    Dans le conscient collectif, l'internat est réputé pour ses qualités normatives et logistiques. Il n'en est pas de même pour ce qui est des besoins affectifs. Si la famille est synonyme d'amour, de partage et de tendresse, l'internat est plutôt synonyme de discipline, de communauté et d'ordre. Ce sont là des représentations courantes, qui ont aussi été les miennes. L'objet de ce travail, est d'éprouver ces représentations, d'identifier ce qui peut effectivement être offert en internat pour ré...

  5. Différenciation paléogéographique à l'Ordovicien supérieur dans le Tafilalt (Anti-Atlas oriental, Maroc) sous l'interaction de la glaciation et de la tectonique

    El Maazouz, Brahim; Hamoumi, Naima

    2007-07-01

    The Tafilalt domain, which corresponded, during the Lower and Middle Ordovician, to a storm and/or tide-dominated epeiric shelf with east-west- to ENE-WSW-trending isopachs, such as the whole 'Anti-Atlasic basin', recorded major palaeogeographical changes during the Upper Ordovician. An extensional tectonic event resulted in the individualization of two sub-basins: the 'Khabt-El-Hejar sub-basin' and the 'western Tafilalt sub-basin', where new environments developed under the interplay between tectonics and glaciation. In the northeastern Tafilalt sub-basin took place an isolated carbonate platform, where Bryozoan mounds nucleated, and a mixed siliciclastic carbonate high-energy peritidal littoral. In the 'western Tafilalt sub-basin', the siliciclastic shelf was structured in half-graben, where sediments from the Saharan glacier and the carbonate platform of the Khabt-El-Hejar sub-basin accumulated in fan deltas.

  6. Le Silurien de la région d'Oulad Abbou (Meseta occidentale, Maroc) : une sédimentation péritidale sous contrôle tectonique

    Attou, Ahmed; Hamoumi, Naima

    2004-07-01

    In the Oulad Abbou syncline, western coastal Meseta, the Silurian deposits exhibit siliciclastic or mixed siliciclastic/carbonate tidal facies that recorded alkaline basalt flows and syn-sedimentary deformations. These facies are staked into peritidal shallowing upward sequences reflecting the evolution from an infratidal to a supratidal environment. These sequences recorded low-amplitude and high-frequency sea-level variations. The built-up of these rhythmic sequences is related to distensive tectonic that allowed the development of isolated platform from extensive siliciclastic influx. This tectonic event is well recorded in the palaeogeographic evolution of the northern Gondwana platform during the Lower Palaeozoic time. To cite this article: A. Attou, N. Hamoumi, C. R. Geoscience 336 (2004).

  7. New facts in mechanism, development and inspection of stress corrosion vulnerability in gas trunk lines; Nouveaux elements dans le mecanisme, le developpement et le diagnostic de la vulnerabilite a la corrosion sous tension des conduites de gaz principales

    Ott, K. [Tyumentransgaz, (Russian Federation)

    2000-07-01

    Stress corrosion cracking (SCC) of the buried pipelines has been acknowledged a serious problem long ago. The author's researches (1) for a long period of time have established that SCC occurrence in pipe metal is affected by a combination of three factors: - Metal quality - availability of structural reasons contributing to occurrence and development of original microcracks; - Appropriate level of active stresses (considering inner residual stresses in the structure of metal), exceeding threshold level for occurrence and development of microcracks at rated operating conditions of the pipeline; - Availability of corrosive environment saturated with soil microorganisms, its access to the metal surface and interaction of the environment and metal structure. Operating failure mechanism and kinetics were proposed for buried pipelines - they give insight into, and enable to classify SCC cases as a local bio-corrosion process occurring in abnormal, in terms of content non-metallic spots, and offer to explain, in full, the features of the process that were hard to interpret before. (author)

  8. The gaseous emission of polymers under swift heavy ion irradiation: effect of the electronic stopping power; L'emission gazeuse des polymeres aliphatiques sous irradiation: effet du pouvoir d'arret electronique

    Picq, V

    2000-07-01

    This thesis contributes to a better understanding of the damaging processes, which occur in polymers under swift heavy ion irradiation. The present study is exclusively devoted to the influence of the electronic stopping power, (dE/dx)e, on the molecular emission under irradiation. The irradiated polymers are polyethylene, polypropylene and poly-butene. The (dE/dx)e of the projectiles used varies from 3.5*10{sup -3} MeV.mg{sup -1}.cm{sup 2} (electron) to 39 MeV.mg{sup -1}.cm{sup 2} ({sup 58}Ni). We used two different experimental approaches in order to identify the nature of the emitted gases: mass spectrometry and infrared spectroscopy. The first technique is non selective, therefore, we could detect the emission of H{sub 2} and heavy molecules; it also gives information on the diffusion kinetics of the molecules formed. The use of infrared spectroscopy for this kind of analysis is new and the technique was developed at the laboratory. It enables us to identify, without any ambiguity, molecules with up to three carbon atoms. The experimental spectra are analysed by using reference spectra of pure gases, measured in our laboratory. We have quantified precisely each identified gas, and we have followed the evolution of the radiochemical yields with increasing (dE/dx)e. The results, obtained at different (dE/dx)e, inform us on the different mechanisms of gas molecules formation, for example the side group departure and, at high (dE/dx)e, the fragmentation of the main chain which is due to multiple ionisation of the macromolecule. (author)

  9. Du cannabis sous les cacaoyers : épuisement du modèle pionnier et reproduction des « institutions de la frontière » en Côte d’Ivoire forestière

    Leonard Eric

    2001-11-01

    Full Text Available Structuration du milieu rural de la zone forestière ivoirienne : rôle de la « frontière interne » et de ses institutions : Kopytoff [1] puis, en référence au contexte ivoirien, Chauveau [2] ont montré à quel point les phénomènes de « frontière interne » ont joué un rôle structurant dans la constitution des espaces nationaux et des champs identitaire, politique et économique en Afrique subsaharienne. En Côte d’Ivoire, l’économie de plantation de café et de cacao, à travers les fronts pionniers qui ont balayé d’est en ouest la moitié méridionale du pays, a ainsi largement contribué au façonnage du système politique et de l’ensemble de la société civile [3]. Au point que la crise économique, politique et institutionnelle que traverse la Côte d’Ivoire depuis la fin des années 80 se superpose dans une large mesure à la crise du secteur exportateur de café et de cacao, elle-même indissociable de l’épuisement des frontières internes et des difficultés que pose la reproduction des systèmes d’exploitation pionniers (voir, entre autres, les lectures de cette crise que proposent Contamin et Memel-Fotê [4] ; Losch [5] ; Ruf [6]. Parmi ces « institutions de la frontière » qui ont tant pesé dans la construction d’un « État paysan » en Côte d’Ivoire et dans l’élaboration d’un mode de gouvernance aujourd’hui en crise [2], celles qui ont encadré la mise en rapport des deux principaux facteurs du boom de l’arboriculture d’exportation - la terre forestière et le travail fourni par les migrants - retiennent d’emblée l’attention, en ce sens qu’elles ont été le véritable support des dynamiques pionnières et ont structuré de façon durable les relations entre les différents acteurs de la dynamique de colonisation - paysans de différentes origines, autorités coutumières, commerçants, représentants des administrations publiques. En particulier, les différentes formes de « tutorat » entre les paysans déjà établis, autochtones ou allogènes, et les nouveaux arrivants ainsi que les échanges de prestations auxquels elles renvoient ont profondément marqué les processus d’installation sur la frontière agricole et d’expansion de la frontière agricole. Elles ont également modelé l’organisation et le fonctionnement des exploitations agricoles en permettant de différer et, souvent, de minorer la rémunération du travail de mise en place et d’entretien des plantations pérennes, en même temps qu’elles institutionnalisaient la prestation de services récurrents au bénéfice des aînés sociaux, bailleurs de la terre. Avec l’épuisement des frontières internes et l’impossibilité de procéder aux échanges de terre et de travail qui fondaient les rapports de tutorat, c’est toutes les relations d’allégeance et de clientélisme entre les différentes composantes de la société pionnière (autochtones et allochtones, aînés et cadets de la migration, paysans et représentants de l’État qui se trouvent remises en question et, avec elles, les fondements même de l’organisation et de la reproduction des exploitations agricoles, sans que la dépression durable des cours internationaux du café et du cacao permette l’expression et la diffusion d’innovations institutionnelles pouvant se superposer et, a fortiori, se substituer aux précédentes. Cette crise des institutions agraires de la frontière semble avoir une incidence directe sur la remise en question des fondements institutionnels du système ivoirien de régulation sociopolitique, à en juger par la position centrale des dynamiques rurales, en général, et des tensions foncières, en particulier, dans le débat politique contemporain et les polémiques sur l’« ivoirité » ou la place allouée aux « étrangers » dans les champs économique et politique nationaux. Le développement récent de la culture et du trafic de cannabis dans les anciens fronts pionniers cacaoyers du Sud-Ouest, dans la mesure où il coïncide avec l’épuisement du modèle pionnier de mise en valeur du milieu et de régulation socio-économique, appelle une lecture attentive des dynamiques institutionnelles qui ont supporté son essor. Il apparaît, en effet, que l’organisation de la production de marihuana et, plus largement, celle de l’ensemble de la filière illicite sont venues soutenir, au moins durant la première moitié des années 90, le fonctionnement des institutions relevant du tutorat et les relations de type clientéliste qui en dérivent : l’innovation technique - l’intégration d’une nouvelle culture dans les systèmes de production - semble en l’occurrence avoir suppléé la dynamique d’innovations institutionnelles dans le champ de la régulation foncière, en permettant la reconduction de rapports sociaux spécifiques de la phase pionnière que l’épuisement de la frontière agricole semblait condamner. De façon plus générale, la production et le commerce de la marihuana semblent avoir fourni un support économique essentiel à des organisations qui avaient accompagné et soutenu le développement des fronts pionniers, non seulement dans le domaine de la production agricole mais aussi dans celui de la mise sur le marché aux niveaux national et international. Les filières de commercialisation intérieure du café et du cacao, durement touchées au cours des années 90 par la restructuration du système de régulation étatique et par l’assèchement des crédits bancaires, semblent, en particulier, avoir rencontré dans le développement des activités illicites un soutien financier que la sphère légale ne pouvait plus leur fournir 1. L’économie du cannabis a ainsi constitué durant la dernière décennie un facteur d’amortissement des crises de différente nature (financière, écologique, sociale qui remettaient en question la reproduction même du tissu d’exploitations agricoles et de relations sociales de tous types constituant la base de l’économie de plantation ivoirienne.

  10. Le vol sous l’œil des médecins légistes. Étude du concept de kleptomanie au cours du XIXe siècle

    Bogani, Lisa

    2016-01-01

    Introduit en 1816 par le Dr Matthey, le concept de kleptomanie connait de multiples évolutions au cours du long xixe siècle. Alors qu’il parvient difficilement à se faire reconnaître des magistrats et des aliénistes du premier xixe siècle, il réussit finalement à se maintenir et à s’assoir solidement dans les prétoires de la iiie République. Entre temps, ses caractéristiques évoluent sensiblement en raison des nouvelles découvertes cliniques de l’aliénation mentale et de l’apparition de la fi...

  11. Study of water radiolysis in relation with the primary cooling circuit of pressurized water reactors; Etude sur la radiolyse de l`eau en relation avec le circuit primaire de refroidissement des reacteurs nucleaires a eau sous pression

    Pastina, B

    1997-07-01

    This memorandum shows a fundamental study on the water radiolysis in relation with the cooling primary circuit of PWR type reactors. The water of the primary circuit contains boric acid a soluble neutronic poison and also hydrogen that has for role to inhibit the water decomposition under radiation effect. In the aim to better understand the mechanism of dissolved hydrogen action and to evaluate the impact of several parameters on this mechanism, aqueous solutions with boric acid and hydrogen have been irradiated in a experimental nuclear reactor, at 30, 100 and 200 Celsius degrees. It has been found that, with hydrogen, the water decomposition under irradiation is a threshold phenomenon in function of the ratio between the radiation flux `1` B(n, )`7 Li and the gamma flux. When this ratio become too high, the number of radicals is not sufficient to participate at the chain reaction, and then water is decomposed in O{sub 2} and H{sub 2}O{sub 2} in a irreversible way. The temperature has a beneficial part on this mechanism. The iron ion and the copper ion favour the water decomposition. (N.C.). 83 refs.

  12. Philipp Thomas et Schumann Christoph (sous la direction de, From the Syrian Land to the States of Syria and Lebanon (Beiruter Texte und Studien 96. Würzburg et Beirut: Ergon Verlag in Kommission, 2004, 7 p. + 366 p.

    Frank Peter

    2007-11-01

    Full Text Available Cet ouvrage collectif, dirigé par Thomas Philipp et Christoph Schumann, réunit 21 contributions portant sur l'émergence de nouvelles identités et idéologies, entre les années 1841 et 1940, dans le Bilâd al-Shâm, la région comprise entre les montagnes du Taurus, le désert syrien, le Sinaï et la Méditerranée. Philipp et Schumann considèrent que peu de recherches ont abordé cette région en tant qu’une unité (as integrated region fondée sur des caractéristiques sociales, culturelles et historiqu...

  13. Thermal and hydrodynamic study of a whirling liquid hydrogen layer under high heat flux; Etude thermique et hydrodynamique d'une couche tourbillonnaire d'hydrogenen liquide sous flux de chaleur eleve

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

    1968-03-01

    In order to achieve a cold neutrons source ({lambda} {>=} 4.10{sup -10} m) in a high flux reactor ({approx} 10{sup 15} neutrons/cm{sup 2}.s), a whirling liquid hydrogen layer (145 mm OD, effective thickness 15 mm, height about 180 mm) was formed, out-of-pile, in a cylindrical transparent glass vessel. The whirling motion was obtained by tangential injection of the liquid, near the wall. Thermal and hydrodynamical conditions of formation and laws of similarity of such a layer were studied. The characteristics of this whirling flow were observed as a function of mass flow rate (5 to 27 g/s; 4.3 to 23 l/mn), and of spillway width (18 and 25 mm). Six different nozzles were used : 1.0; 1.5; 1.9; 2.25; 2.65 and 3.0 mm ID. The total heat influx was found between 8.6 and 10.4 kW. The heat flux density was about 9.4 W/cm{sup 2} and the mean layer density around 80 per cent of that of the liquid hydrogen at 20.4 Kelvin. High speed movies were used to analyze the boiling regime. (author) [French] En vue de realiser une source de neutrons froids ({lambda} {>=} 4.10{sup -10} m) dans un reacteur a haut flux ({approx} 10{sup 15} neutrons thermiques/cm{sup 2}.s), on a forme dans un vase cylindrique transparent en verre, hors-pile, une couche tourbillonnaire ('vortex') d'hydrogene liquide (diametre exterieur 145 mm, epaisseur effective 15 mm, hauteur 180 mm environ). Le mouvement giratoire est obtenu par injection tangentielle du liquide pres de la paroi. L'etude porte sur la determination des conditions thermiques et hydrodynamiques de la formation d'une telle couche et sur les regles de similitude de ce phenomene. On a observe les caracteristiques de l'ecoulement giratoire en fonction du debit (de 5 a 27 g/s, soit de 4.3 a 23 1/mn), de la vitesse d'injection (entre 10 et 110 m/s) et de la largeur du deversoir (18 et 25 mm), ceci pour six diametres differents d'injecteur (1.0 ; 1.5; 1.9; 2.25; 2.65 et 3.0 mm). Le flux de chaleur total mesure est compris entre 8.6 et 10.4 kW et la densite de flux de chaleur est de 9.4 W/cm{sup 2} environ. La masse volumique moyenne de la couche est voisine de 80 pour cent de celle de l'hydrogene liquide a 20.4 K. Le cinema rapide a ete utilise pour analyser le regime d'ebullition. (auteur)

  14. Etude du comportement au champ et des performances de cinq variétés de niébé sous apport d'éléments traces à Yangambi (Zaïre

    Lumpungu, K.

    1986-01-01

    Full Text Available Study of performances on field of five Niebe varieties with trace elements supplements in Yangambi (Zaire. Response of five cowpea varieties to Mg and trace elements applied by soaking seeds before sowing was studied in field conditions at Yangambi. Neither the grain yield, nor the lipid content of grains were influenced by these elements. However, protein content of grains of all the five tested varieties was positively influenced. The increase was of up to 39 %. In the same way, Mg and trace elements positively influenced the number of seedlings and the number of attacked grains was decreased in the three new introduced varieties from the I.I.T.A./lbadan, Nigeria.

  15. Lidija Šega: Veliki moderni poslovni slovar. Angleško-slovenski; sous la direction éditoriale de Mojca Hočevar, Cankarjeva založba, Ljubljana, 1997

    Gregor Perko

    1999-12-01

    Full Text Available L'intemationalisation des échanges commerciaux et des structures économiques, la mise en place d'organismes supranationaux et l 'essor du tourisme, pour ne citer que quelques facteurs, contribuent à créer dans la lexicographie bilingue européenne des exigences constamment renouvelées et auxquelles les maisons d'édition tentent de répondre de manières différentes. D'un côté, les dictionnaires bilingues généraux réservent une place de plus en plus importante aux termes issus des vocabulaires économique, juridique et politique. On constate, d'un autre côté, que, depuis les années soixante, le nombre de dictionnaires bilingues (et plurilingues consacrés exclusive­ ment aux différentes langues de spécialités n'a cessé d'augmenter.

  16. STUDY CONCERNING THE PRODUCTION OF BIOMASS PROTEIN BY VALORISATION OF BY-PRODUCTS FROM THE DAIRY INDUSTRY ETUDE CONCERNANT L’OBTENTION DE BIOMASSE PROTEIQUE PAR VALORISATION DES SOUS-PRODUITS DE L’INDUSTRIE LAITIERE

    LUMINITA GROSU

    2015-07-01

    Full Text Available The development of the food industry ensures the necessary protein for the population and in this perspective the valorisation of by-products from the dairy industry (whey and buttermilk can be a solution in this direction. Whey is a very important substrate for the biosynthesis of single cell protein by its lactose content which is the main source of fermentable substrate for yeasts. As part of our research, the biomass protein was obtained using whey as source of lactose and other sugars and yeast strains of Candida utilis. The modelling program used is 2nd order system centred with three variables: amount of sugar, amount of nitrogen and quantity of phosphorus. The following parameters have been pursued: biomass content, yield of sugar consumption and protein content. The process conditions are influenced by the addition of different nutrients.

  17. Le siège Mers-el-Kebir sous le siège de 1563 et la dimension spatio-temporelle dans “ El Gallardo espagnol ” de M. de Cervantes

    Abi Ayad, Ahmed

    2013-01-01

    Nous avons choisi l’œuvre du grand romancier espagnol de l’époque moderne pour illustrer notre thématique relative à la dimension spatio-temporelle dans le Gallardo espagnol de Miguel de Cervantes.Nous essayons d’abord de vous exposer l’argument fondamental de cette pièce dramatique qui relate un événement capital de l’histoire d’Oran et des affrontements avec l’occupation espagnole, suite à conquête des places de Mers- el-Kebir et d’Oran en 1504 et 1509.Miguel de Cervantes s’inspire ici du c...

  18. Feasibility study for the installation of a small hydro electric power plant; Etude de faisabilite. Petite centrale hydro-electrique au lieu dit 'Sous les Roches' a Sonceboz

    Tissot, N. [MHyLab, Mini-Hydraulics Laboratory, Montcherand (Switzerland); Hausmann, H. [Hans Hausmann, Bevilard (Switzerland)

    2003-07-01

    This report for the Swiss Federal Office of Energy presents a technical, economical and ecological analysis of the feasibility of a small hydroelectric power plant at Sonceboz, in the Swiss Jura mountains. The power of the planed plant would typically be 500 kW for a water head of about 10 m. The study shows that, compared to one single turbine, a pair of Kaplan type turbines would be operational over a larger range of the river's water flow rate. This solution would be a little bit more costly but offer more flexibility for maintenance. Two maximum water flow rates are considered, 4.5 and 6 m{sup 3}/s respectively. According to the economical study, done with current electric kWh prices, both configurations are viable while the largest flow rate leads to a larger profit. The report is rounded up by a sensitivity analysis considering variations in annual power generation, electro-mechanical and construction cost as well as turbine efficiency. It indicates that this last factor could be crucial for the overall profitability. [French] Ce rapport est le resultat detaille de l'analyse technico-economique et ecologique de faisabilite de la realisation d'une petite centrale hydroelectrique basse chute qui pourrait exploiter une denivellation d'environ 10 m pour une puissance de l'ordre de 500 kW pres de Sonceboz dans le Jura suisse. L'etude montre que le couplage de deux turbines Kaplan offrirait une possibilite de fonctionnement sur une plus grande plage de flux ainsi qu'une plus grande flexibilite de maintenance, ceci pour un cout legerement superieur a l'option a une seule turbine. Les debits de 4.5 et 6 m{sup 3}/s sont consideres. L'etude economique montre que le debit de 6 m{sup 3}/s est plus rentable au prix de vente actuel du kWh. L'article se termine par une analyse de sensibilite sur les incertitudes concernant la production annuelle, les prix de l'electromecanique et du genie civil et le rendement des turbines.

  19. Under - diaphragm irradiation of an osseous stage 4 Hodgkin lymphoma at a patient whose pregnancy was unknown; Irradiation sous-diaphragmatique d'un lymphome hodgkinien de stade 4 osseux chez une patiente dont la grossesse etait meconnue

    Moreau, M.V.; Tournier-Rangeard, L.; Brunaud, C.; Marchesi, V.; Peiffert, D. [Centre Alexis-Vautrin, Service de Radiotherapie, 54 - Vandoeuvre-les-Nancy (France); Bologna, S. [Centre Hospitalier Universitaire Brabois, Service d' Hematologie, 54 - Vandoeuvre-les-Nancy (France)

    2007-11-15

    Four years after the irradiation, the patient was in situation of complete forgiveness: the child was normal, there was neither a deformation nor a mental disorder, but the neoplastic risk persists, thus long-term surveillance is imperative. If the pregnancy is known, we have to arrest the foetal risks incurred in order to propose a termination of pregnancy; therefore, are made the measures on phantoms of the dose that he would receive, according to the tumoral localization, to the dose necessary to eradicate the tumor, to the field and the possible masks for an optimal tumoral control. (N.C.)

  20. Physionomies et héritages de la dictature pinochétiste : du terrorisme d’État à la mise sous tutelle du processus transitionnel (1973-2015

    Nicolas Prognon

    2015-12-01

    Full Text Available On September 11, 1973, a military junta – under general Augusto Pinochet’s authority – overthrew Salvador Allende’s government. This military regime, which remained in power until the day of the investiture of President Patricio Aylwin, in March 1990, managed to strengthen its power by abolishing existing institutions and by promulgating a new constitution in 1980. Then, “president” Pinochet orchestrated the end of the regime and decided to take control of the transitional period towards democracy by locking (shutting down the political system. Yet, albeit that the country commemorated the 40th anniversary of the coup d’État in 2013, the scars from the way the transition was brought about in 1990, as well as the political legacy of the dictatorship are still dividing the Chilean society.

  1. Élaboration et évaluation d’un protocole de coopération pluriprofessionnel visant à améliorer la prise en charge des patients sous AVK dans un territoire donné

    Postel-Vinay Croharé, Constance

    2016-01-01

    Introduction : les antivitamines K (AVK) ont une marge thérapeutique étroite d’où un traitement à fort potentiel iatrogène encore mal maîtrisé : le temps moyen passé en zone thérapeutique (TTR) excède rarement 65% en France. Leur gestion exige une coordination serrée entre professionnels de santé et avec le patient. Cette thèse présente l’élaboration et l’évaluation d’un protocole visant à améliorer la coordination des différents professionnels de santé autour d’un patient traité par AVK pour...

  2. Embrittlement and anodic process in stress corrosion cracking: study of the influent micro-mechanical parameters; Fragilisation et processus anodiques en corrosion sous contrainte: etude des parametres micro-mecaniques influents

    Tinnes, J.Ph

    2006-11-15

    We study the influence of local mechanical parameters on crack propagation in Stress Corrosion Cracking, at the scale of the microstructure. Two systems are compared: the CuAl{sub 9}Ni{sub 3}Fe{sub 2} copper-aluminium alloy in synthetic sea water under cathodic polarization, where the crack propagation mechanism is related to strain-assisted anodic dissolution, and the 316L austenitic stainless steel in MgCl{sub 2} solution, where embrittlement mechanisms related to hydrogen effects prevail. We use micro-notched tensile specimen that allow to study isolated short cracks. These experiments are modelled by means of finite elements calculations, and further characterized by Electron Back scattered Diffraction (EBSD) in the case of the 316L alloy. In terms of the local mechanical parameters that control propagation, fundamental differences are outlined between the two systems. They are discussed from the viewpoint of the available models of Stress Corrosion Cracking. (author)

  3. Study and simulation of the behaviour under irradiation of helium in uranium dioxide; Etude et modelisation du comportement sous irradiation de l'helium dans le dioxyde d'uranium

    Martin, G

    2007-06-15

    Large quantities of helium are produced from {alpha}-decay of actinides in nuclear fuels during its in-pile operating and its storage. It is important to understand the behaviour of helium in these matrix in order to well simulate the evolution and the resistance of the fuel element. During this thesis, we have used nuclear reaction analyses (NRA) to follow the evolution of the helium implanted in polycrystalline and monocrystalline uranium dioxide (UO{sub 2}). An experimental rig was developed to follow the on-line helium release in UO{sub 2} and the evolution of {sup 3}He profiles as a function of annealing temperature. An automated procedure taking into account the evolution of the depth resolution was developed. Analyses performed with a nuclear microprobe allowed to characterise the spatial distribution of helium at the grain scale and to study the influence of the sample microstructure on the helium migration. This work put into evidence the particular role of grain boundaries and irradiation defects in the helium release process. The analyse of experimental results with a diffusion model corroborates these interpretations. It allowed to determine quantitatively physical properties that characterise the helium behaviour in uranium dioxide (diffusion coefficient, activation energy..). (author)

  4. A 20 MW podded ship underwater electromagnetic signature - the alternative electric field; Signature electromagnetique sous-marine d'un paquebot de 20 MW a pods - le champ electrique alternatif

    Lucas, B.; Henocq, H.; Rannou, C. [Delegation Generale pour l' Armement, DET/GESMA, 75 - Paris (France); Albert, Th.; Harpin, D. [ALSTOM Marine (France); Bourguet, S.; Guerin, P. [Institut de Recherche en Electrotechnique et Electronique de Nantes Atlantique, 44 (France)

    2006-03-15

    Today, electric podded propulsion is used for many ships, cruise liners and Navy vessels.This propulsion uses high currents in extremely low frequencies (ELFE); currents flow through electrical network, equipment and pods. These alternative currents could generate important underwater electromagnetic field. GESMA has to quantify the level of this field and its impact on the signature of this kind of ship. Then, GESMA carried out electromagnetic measurements using a multi-sensors underwater and autonomous facility named AMI. It was placed on the route of a 20 MW podded ship, at one hundred meters depth from the surface. Especially, AMI observed an alternative radiated electric field... (authors)

  5. Complexation des acides aminés basiques arginine, histidine et lysine avec l'ADN plasmidique en solution aqueuse : participation à la capture de radicaux sous irradiation X à 1,5 keV

    Tariq Khalil, Talat; Taillefumier, Baptiste; Boulanouar, Omar; Mavon, Christophe; Fromm, Michel

    2016-09-01

    L'environnement chimique de l'ADN en situation biologique est complexe notam-ment en raison de la présence d'histones, protéines nucléaires, associées en quantité approximativement égales à l'ADN pour former la chromatine. Les histones possèdent de nombreux radicaux basiques arginine et lysine chargés positivement et dont la majorité se trouve sur les chaînes émergentes, l'ADN présente quant à lui des charges négatives sur ses groupements phosphates localisés tout au long de la double hélice. Dans cette étude, la complexité de la structure de la chromatine nucléaire est dans un premier temps mimée en solution aqueuse par la formation de complexes entre un ADN plasmidique sonde et les trois acides aminés basiques, Arg, His, Lys, qui, mis à part His, sont protonés au pH physiologique. Ces acides aminés libres en solution sont réputés être des capteurs efficaces de radicaux libres, notamment pour le radical hydroxyle, conférant ainsi un pouvoir protecteur vis-à-vis des effets indirects sur l'ADN en situation d'exposition aux rayonnements ionisants. A concentration fixée, les capacités de capture des acides aminés libres, σ, pour le radical hydroxyle sont typiquement les suivantes σHis ≈σArg > σLys (σLys ≈ 0,1 × σArg). Nous avons mesuré les taux de cassures simple brin par plasmide et par Gray (χ) lors d'expositions de solutions aqueuses de complexes [acide aminé - ADN plasmidique] aux rayons X ultra-mous (1,5 keV). A concentrations égales, les trois acides aminés complexés et présents en large excès ne manifestent pas une capacité de protection de l'ADN proportionnelle à leur capacité de capture libre et en solution ; on trouve en effet des taux de cassures dans l'ordre suivant χHis > χArg > χLys (χLys ≈ 0,01 χArg). Après avoir détaillé le mode opératoire de ces mesures, nous analyserons sur des bases bibliographiques, les modes spécifiques d'interaction des acides aminés basiques avec l'ADN. La spécificité des liaisons de l'arginine avec l'ADN et plus particulièrement sa propension à être un ligand bidentate qui se lie aux bases (principalement G) de l'ADN nous permet d'expliquer les taux de cassures simple brin particulièrement élevés observés avec Arg. Un mécanisme de transfert de radical intermoléculaire est suggéré pour Arg. Un raisonnement globalement similaire peut être tenu pour la lysine. Pour l'histidine, nous suggérons quelques voies possibles qui conduiraient à expliquer les taux de cassure anormalement élevés observés, mais cela demandera des expériences complémentaires.

  6. Study of colloidal particles behaviour in the PWR primary circuit conditions; Etude du comportement des particules colloidales dans les conditions physicochimiques du circuit primaire des reacteurs a eau sous pression

    Barale, M

    2006-12-15

    EDF wants to understand, model and limit primary circuit contamination of Pressurized Water Reactors by colloidal particles resulting from corrosion. The electrostatic behaviour of representative oxide particles (cobalt ferrite, nickel ferrite and magnetite) has been studied in primary circuit conditions with the influence of boric acid and lithium hydroxide. The isoelectric point (IEP) and the point of zero charge (PZC) of particles, measured between 5 C and 320 C, exhibit a minimum towards 200 C. The thermodynamic constants of the protonation equilibrium of surface sites were calculated. When boric acid is added, zeta potential and IEP decrease because of borate ions sorption. On the contrary, there is not effect of lithium ions. The modelling of these results under conditions representative of primary circuit shows that these oxides exhibit a negative surface charge, explaining their sorption and adhesion behaviour. (author)

  7. Fabrication, characterization and radiation damage stability of hollandite based ceramics devoted to radioactive immobilisation; Synthese, caracterisation et etude du comportement sous irradiation electronique de matrices de type hollandite destinees au confinement du cesium radioactif

    Aubin-Chevaldonnet, V. [CEA Valrho, Dir. de l' Energie Nucleaire (DEN/DETCD/SCDV), Dept. d' Etudes du Traitement et du Conditionnement des Dechets, Service de Conditionnement des Dechets et Vitrification, 30 - Marcoule (France)

    2004-11-01

    Research on treating specifically the long-lived and high level nuclear wastes, notably cesium, is currently carried out in France. Cesium immobilization in host matrices of high chemical durability constitutes the favoured option. Hollandite matrix is a good candidate because of its high cesium incorporation ability and its excellent chemical stability. During this study, different compositions of hollandite ceramics Ba{sub x}Cs{sub y}C{sub z}Ti{sub 8-z}O{sub 16} (C = Al{sup 3+}, Cr{sup 3+}, Ga{sup 3+}, Fe{sup 3+}, Mg{sup 2+}, Sc{sup 3+}), synthesized by oxide route, were characterized in terms of structure, microstructure and physical and chemical properties. Iron ions seems to be the most suitable of the studied C cations to get high-performance hollandites. The stability of these ceramics under external electron irradiation, simulating the {beta} particles emitted by radioactive cesium, were also estimated, at the macroscopic and atomic scale. The point defects creation and their thermal stability were followed by electron paramagnetic resonance. (author)

  8. Contribution to the optimization of the chemical and radiochemical purification of pressurized water nuclear power plants primary coolant; Contribution a l'optimisation de la purification chimique et radiochimique du fluide primaire des centrales nucleaires a eau sous pression

    Elain, L

    2004-12-15

    The primary coolant of pressurised water reactors is permanently purified thanks to a device, composed of filters and the demineralizers furnished with ion exchange resins (IER), located in the chemical and volume control system (CVCS). The study of the retention mechanisms of the radio-contaminants by the IER implies, initially, to know the speciation of the primary coolant percolant through the demineralizers. Calculations of theoretical speciation of the primary coolant were carried out on the basis of known composition of the primary coolant and thanks to the use of an adapted chemical speciation code. A complementary study, dedicated to silver behaviour, considered badly extracted, suggests metallic aggregates existence generated by the radiolytic reduction of the Ag{sup +} ions. An analysis of the purification curves of the elements Ni, Fe, Co, Cr, Mn, Sb and their principal radionuclides, relating to the cold shutdown of Fessenheim 1-cycle 20 and Tricastin 2-cycle 21, was carried out, in the light of a model based on the concept of a coupling well term - source term. Then, a thermodynamic modelling of ion exchange phenomena in column was established. The formation of the permutation front and the enrichment zones planned was validated by frontal analysis experiments of synthetic fluids (mixtures of Ni(B(OH){sub 4}){sub 2}, LiB(OH){sub 4} and AgB(OH){sub 4} in medium B(OH){sub 3})), and of real fluid during the putting into service of the device mini-CVCS at the time of Tricastin 2 cold shutdown. New tools are thus proposed, opening the way with an optimised management of demineralizers and a more complete interpretation of the available experience feedback. (author)

  9. Study and simulation of a multi-lithology stratigraphic model under maximum erosion rate constraint; Etude et simulation d'un modele statigraphique multi-lithologique sous contrainte de taux d'erosion maximal

    Gervais, V.

    2004-11-01

    The subject of this report is the study and simulation of a model describing the infill of sedimentary basins on large scales in time and space. It simulates the evolution through time of the sediment layer in terms of geometry and rock properties. A parabolic equation is coupled to an hyperbolic equation by an input boundary condition at the top of the basin. The model also considers a unilaterality constraint on the erosion rate. In the first part of the report, the mathematical model is described and particular solutions are defined. The second part deals with the definition of numerical schemes and the simulation of the model. In the first chap-ter, finite volume numerical schemes are defined and studied. The Newton algorithm adapted to the unilateral constraint used to solve the schemes is given, followed by numerical results in terms of performance and accuracy. In the second chapter, a preconditioning strategy to solve the linear system by an iterative solver at each Newton iteration is defined, and numerical results are given. In the last part, a simplified model is considered in which a variable is decoupled from the other unknowns and satisfies a parabolic equation. A weak formulation is defined for the remaining coupled equations, for which the existence of a unique solution is obtained. The proof uses the convergence of a numerical scheme. (author)

  10. Study of the initiation and the propagation of cracks under 3D thermal cyclic loading; Etude de l'amorcage et de la propagation des fissures sous chargement thermique cyclique 3D

    Ancelet, O

    2005-07-01

    The incident which has occurred on the Civaux power plant has shown the noxiousness of thermal loading and the difficulty to take it into account at design level. The objective of this report is to study the initiation and the propagation of crack under thermal loading. In this aim the CEA has developed a new experiment named FAT3D. The various experiments carried out showed the harmfulness of a thermal loading, which makes it possible to rapidly initiate a network of cracks and to propagate one (or some) cracks through the totally thickness of the component under certain conditions. These experimental results associated with a mechanical analysis put at fault the usual criteria of damage based on the variations of the equivalent strain. In addition, the study of the propagation stage shows the importance of the plasticity which, in the case of a thermal loading, slows down the propagation of the crack. (author)

  11. Chenu F. (2015). L’évaluation des compétences professionnelles. Une mise à l'épreuve des notions et présupposés théoriques sous-jacents

    Wittorski, Richard

    2016-01-01

    Dans son ouvrage intitulé L’évaluation des compétences professionnelles, Florent Chenu s’intéresse à une question « chargée » tant sur le plan scientifique (définitions multiples du terme compétence, souvent aujourd’hui considéré comme un « mot valise ») que sur le plan social (des enjeux et débats sociaux vifs concernant les modalités d’évaluation des compétences et, au-delà, concernant la façon de les reconnaître dans les milieux du travail). Dans ce contexte particulier, proposer une publi...

  12. Facteurs socio-économiques affectant l'utilisation des sous-produits agro-industriels pour l'embouche bovine à contre-saison dans l'Adamaoua, Cameroun

    Deffo V.

    2009-01-01

    Full Text Available Socio-economic factors affecting the use of agro-industrial by-products for cattle fattening in the dry season in Adamawa, Cameroon. Cattle production is the major economic activity in the Adamawa. Feed deficiency that causes about 129 to 187 g weight loss per day is an important constraint during the dry season. A possible alternative to overcome this constraint is the use of agro-industrial by-products. However, the adoption and effective use of these potentials are still to be encouraged. This study, which objective was to find out the socio-economic factors that may affect the usage of these resources, permitted to show, through interviews and surveys, that more than 8,200 t of agro-industrial by-products (maize and wheat bran, soybean seed and maize seed cake useable for cattle feeding were produced annually in Adamawa and that only 16 % of this production were used by livestock farmers. Among the factors affecting the effective use of these by-products, prices were the most determinant. The herds size and the number of sedentary animals had also shown a significant positive effect. On the other hand, livestock farming experience and the farmer’s age had instead shown a strong negative correlation with the use of by-products; same was the level of farmer’s education which showed positive correlation only with respect to cotton seed cake use. The distance from the livestock farming sites to the by-products production/distribution centre and/or difficult access to the sites had strong positive correlations with the by-products’ prices. The problem of supplies as a result of long distance or of difficult access to cattle production sites, the high and unstable prices of agro-industrial by-products and poor awareness of the different types of by-products produced in the Adamawa, were noted as major constraints for their use as cattle feed. Based on the above results, an effective extension system and well organized farmers groupings could improve the level of utilization of agro-industrial by-products for cattle feeding.

  13. BLANCHIMENT ACCÉLÉRÉ DES ŒUFS NON FÉCONDÉS DE TRUITE ARC-EN-CIEL (ONCORHYNCHUS MYKISS SOUS L’EFFET DE SOLUTIONS SALINES EN VUE DE LEUR TRI MÉCANIQUE

    MILLA S.

    2007-01-01

    Full Text Available Le blanchiment des œufs non fécondés dans les pontes de salmonidés en incubation artificielle permet leur élimination par tri mécanique. Le déclenchement de ce phénomène normalement plus ou moins tardif durant l’incubation a pu être accéléré grâce à une brève exposition des œufs à une solution de sel de mer. Les modalités et les effets de cette exposition sur les taux de mortalité et de malformations des embryons ont été testés sur des pontes de truite arc-en-ciel à divers stades de développement (140, 190 et 240 degrés*jours. Le passage durant 1 à 20 min dans une solution saline de 30 à 120 g/l a permis d’augmenter significativement le taux de blanchiment des œufs non fécondés sans affecter celui des œufs fécondés. Toutefois, par un effet mécanique, la manipulation nécessaire au traitement a entraîné une augmentation significative de la mortalité embryonnaire pour une manipulation à 140 degrés*jours et du taux de malformations larvaires pour une manipulation à 190 degrés*jours. A 240 degrés*jours, la manipulation n’a pas affecté le développement embryonnaire mais a entraîné un retard de l’éclosion de quelques heures. Cette étude offre de nouvelles perspectives pour améliorer le tri mécanique des œufs fécondés et non fécondés au cours de l’incubation chez la truite arc-en-ciel.

  14. Deformation and damage modes of deep argillaceous rocks under hydro-mechanical stresses; Modes de deformation et d'endommagement de roches argileuses profondes sous sollicitations hydro-mecaniques

    Vales, F.

    2008-12-15

    An experimental identification of the hydro-mechanical behaviour of an argillite rock is proposed within a multi-scale approach. In particular, interest is focused on the spatial and temporal localization of strain and damage in a specimen during hydro-mechanical loading. Firstly, we describe the techniques used to follow the rock evolutions under loading, and in particular Digital Images Correlation (DIC), Acoustic Emission, microscopy and mercury intrusion porosimetry. Measurement errors and device limitations are discussed. The studied material is the Callovo-Oxfordian indurated argillaceous rock (or argillite) of the Bure site where ANDRA has built an underground research laboratory to study the radioactive waste storage. Petrophysical characterizations and microstructural observations by optical and scanning electron microscopy provide an identification of the constitutive phase and a characterization of their spatial distribution and typical sizes. Argillite can be described as a composite structure with a continuous clay matrix and embedded mineral particles, essentially quartz and carbonates. The typical size of these particles ranges from a few micrometers to a few hundreds micrometers, with an average close to 50 {mu}.m. The general experimental procedure combines two steps: in a fist time, imposed suctions bring samples to a given degree of water saturation, and, in a second time, uniaxial mechanical compression tests are performed. To understand the evolutions of the material under hydric and mechanical loading, samples are instrumented with standard measurement techniques, but also with Digital Image Correlation, at both the global scale of the sample and the local scale of the composite microstructure, and with Acoustic Emissions recording. Moisture transfers are imposed by controlled suctions on the range of 150 to 2.8 MPa, corresponding to the relative humidity range of 32 to 98%RH. During pure hydric solicitation, the changes in physical parameters (weight, longitudinal and transverse strains) are continuously recorded until stabilization. When sample equilibrium is reached, uniaxial compressive tests are performed. Samples brought to lower relative humidity undergo an anisotropic shrinkage associated with a water content decrease. Samples in equilibrium at 98%RH swell and store water. Depending of the clay ratio, a significant contribution to this swelling can be shown to be due to the opening of these preexisting cracks and to the creation of new cracks. The macroscopic mechanical response and in particular its linearity and the spatial homogeneity of the strain distribution, depend on the initial rock microstructure (clay ratio) and on the microstructure induced by the suction (new crack network). When suction increases from 2.8 to 150 MPa, Young modulus and strength increase with a factor respectively close to 2 and 3. For dry states, macroscopic strain fields are homogeneous while at the microstructure scale, strain are heterogeneous and clearly correlated with the local distribution of mineral constituents; clayey areas are more deformable than other mineral phase. For wet states, overall and local strain fields are heterogeneous. Strain are affected by the presence of the cracks: close to them, local strain are important but at a distance from cracks large than a few hundreds micrometers, strain distributions are similar to those in the dry states. The main behaviour difference between dry and wet states seems to be due more to the presence of cracks induced by the suctions, than to an intrinsic evolution of the mechanical properties of the clay matrix. The multi-scale quantification of strain heterogeneity by Digital Image Correlation, and the determination of the damage appearance by Acoustic Emission, are useful input data for the development and validation of multi-scale constitutive models for argillite. (author)

  15. Primary processes in radiation chemistry. LET (Linear Energy Transfer) effect in water radiolysis; Processus primaires en chimie sous rayonnement. Influence du transfert d'energie lineique sur la radiolyse de l'eau

    Trupin-Wasselin, V

    2000-07-11

    The effect of ionizing radiations on aqueous solutions leads to water ionization and then to the formation of radical species and molecular products (e{sup -}{sub aq}, H{sup .}, OH{sup .}, H{sub 2}O{sub 2}, H{sub 2}). It has been shown that the stopping power, characterized by the LET value (Linear Energy Transfer) becomes different when the nature of the ionizing radiations is different. Few data are nowadays available for high LET radiations such as protons and high energy heavy ions. These particles have been used to better understand the primary processes in radiation chemistry. The yield of a chemical dosimeter (the Fricke dosimeter) and those of the hydrogen peroxide have been determined for different LET. The effect of the dose rate on the Fricke dosimeter yield and on the H{sub 2}O{sub 2} yield has been studied too. When the dose rate increases, an increase of the molecular products yield is observed. At very high dose rate, this yield decreases on account of the attack of the molecular products by radicals. The H{sub 2}O{sub 2} yield in alkaline medium decreases when the pH reaches 12. This decrease can be explained by a slowing down of the H{sub 2}O{sub 2} formation velocity in alkaline medium. Superoxide radical has also been studied in this work. A new detection method: the time-resolved chemiluminescence has been perfected for this radical. This technique is more sensitive than the absorption spectroscopy. Experiments with heavy ions have allowed to determine the O{sub 2}{sup .-} yield directly in the irradiation cell. The experimental results have been compared with those obtained with a Monte Carlo simulation code. (O.M.)

  16. Study of hydrogenated amorphous silicon devices under intense electric field: application to nuclear detection; Etude de dispositifs electroniques en silicium amorphe hydrogene sous fort champ electrique: application a la detection nucleaire

    Ilie, A. [CEA Centre d`Etudes de Saclay, 91 - Gif-sur-Yvette (France). Direction des Technologies Avancees]|[Paris-11 Univ., 91 - Orsay (France)

    1996-12-31

    The goal of this work was the study, development and optimization of hydrogenated amorphous silicon (a-Si:H) devices for use in detection of ionizing radiation. Thick p-i-n devices, capable of withstanding large electric fields (up to 10{sup 6} V/cm) with small currents (nA/cm{sup 2}), were developed. To decrease fabrication time, films were made using the `He diluted` PECVD process and compared to standard a-Si:H films. Aspects connected to specific detector applications as well as to the fundamental physics of a-Si:H were considered: the internal electric field technique, in which the depletion charge was measured as a function of the applied bias voltage; study of the leakage current of p-i-n devices permitted us to demonstrate different regimes: depletion, field-enhanced thermal generation and electronic injection across the p layer. The effect of the electric field on the thermal generation of the carriers was studied considering the Poole-Frenkel and tunneling mechanisms. A model was developed taking under consideration the statistics of the correlated states and electron-phonon coupling. The results suggest that mechanisms not included in the `standard model` of a Si:h need to be considered, such as defect relaxation, a filed-dependent mobility edge etc...; a new metastable phenomenon, induced by prolonged exposure to a strong electric field, was observed and studied. It is characterized by marked decrease of the leakage current and the detector noise, and increase in the breakdown voltage, as well as an improvement of carrier collection efficiency. This forming process appears to be principally due to an activation of the dopants in the p layer; finally, the capacity of thick p-i-n a Si:H devices to detect ionizing radiation has been evaluated. We show that it is possible, with 20-50 micron thick p-i-n devices, to detect the full spectrum of alpha and beta particles. With an appropriate converter, neutron detection then becomes possible. (author). 137 refs.

  17. Kinetic Modeling of Vacuum Gas Oil Hydrotreatment using a Molecular Reconstruction Approach Modélisation cinétique de l’hydrotraitement de distillats sous vide utilisant une approche de reconstruction moléculaire

    Charon-Revellin N.; Dulot H.; López-García C.; Jose J.

    2010-01-01

    Vacuum Gas Oils (VGO) are heavy petroleum cuts (boiling points ranging from 350 to 550 ˚C) that can be transformed into valuable fuels (gasolines, diesels) by fluid catalytic cracking or hydrocracking. Prior to these conversion processes, hydrotreating is required in order to eliminate the impurities in VGOs. The hydrotreatment process enables to meet the environmental specifications (total sulfur contents) and to prevent nitrogen poisoning of conversion catalysts. In order to develop a kinet...

  18. Stress corrosion cracking in the vessel closure head penetrations of French PWR`s; Fissuration par corrosion sous contrainte de penetrations de couvercle de cuve de reacteur nucleaire francais a eau pressurisee

    Buisine, D.; Cattant, F.; Champredonde, J.; Pichon, C.; Benhamou, C.; Gelpi, A.; Vaindirlis, M.

    1994-01-01

    During a hydrotest in September 1991, part of the statutory decennial in-service inspection, a leak was detected on the vessel head of Bugey 3, which is one of the first 900 MW 3-loop PWR`s in France. This leak was due to a cracked penetration used for a control rod drive mechanism. The investigations performed identified Primary Stress Corrosion Cracking of Alloy 600 as being the origin of this degradation. So a lot of the same design PWR`s are a concern due to this generic problem. In this case, PWSCC was linked to: - hot temperature of the vessel head; - high residual stresses due to the welding process between peripherical penetrations and the vessel head; - sensitivity of forged Alloy 600 used for penetration manufacturing. This following paper will present the cracked analysis based, in particular, on the main results obtained in France on each of these items. These results come from the operating experience, the destructive examinations and the programs which are running on stress analysis and metallurgical characterizations. (authors). 9 figs., 2 tabs.

  19. Contribution to the study of metallic impurities diffusion in a polymer film (KAPTON) under and out of irradiation; Contribution a l`etude de la diffusion d`impuretes metalliques dans un film polymere (KAPTON) sous et hors irradiation

    Marin, N

    1995-12-18

    The main topic of this work is the diffusion behaviour in the polymer film Kapton, under and out of irradiation, of metallic coatings with different reactivity (copper, nickel, titanium) deposited by sputtering. The analysis of diffusion profiles has been performed by backscattering spectrometry, which, in association with cross-section microscopy, allows to connect the diffusion behaviour to the microscopic structure of the metal/Kapton interface. Generally speaking, the study under thermal annealing shows the importance of peculiarities of commercials polymers. In particular, additional elements they contain are liable to modify their surface characteristics and, as a consequence, diffusion. So, unlike observations in model polyimides, we show that even weakly reactive metals do not diffuse inside the polymer. Besides, there exists an energy threshold of Ar{sup +} used for sputtering, above which copper layers become very stable and so come up to industry`s expectation. The study under irradiation gives evidence for copper diffusion under irradiation, resulting in 15 mn mean radius spherical clusters inside the modified polymer. This fast diffusion is shown to be due to the concomitant effect of nuclear collisions and temperature. This study is also the opportunity to show dramatic radiation-induced effects in Kapton, more particularly a large modification of mechanical and optical properties with the loss of more volatile elements (H, N,O). With regard to methodology, this study shows the strong ambiguity in the RBS spectrum interpretation in the case of lateral non-uniformity, and we propose a model giving access to the statistical distribution of the non-uniform property of the target. (author). 262 refs., 99 figs., 8 appends.

  20. Dynamique d'expansion des cacaoyères dans les zones de contact forêt-savane : cas de la sous-préfecture de Kokumbo (Centre de la Côte d'Ivoire

    Kpangui, KB.

    2018-01-01

    Full Text Available Cocoa Expansion Dynamics in the Forest-Savanna Contact Zones: Case Study of the Sub-prefecture of Kokumbo (Côte d'Ivoire. In Ivory Coast, forests-savannah transition areas have been considered from the 1970s as unfavorable to cocoa cultivation. In recent years, however, there has been a comeback to the cocoa economy in these areas. This study carried out in the sub-prefecture of Kokumbo, aimed to map and to follows the spatial and temporal evolution of this crop using Landsat images of 1990, 2002 and 2016. In order to better understand the fundamentals of the peasant practices, surveys were carried out in different villages in the area. Treatment shows that the influence of cocoa culture is becoming increasingly important in the region. This cocoa crop is set up to the detriment of forests and savannahs, which have lost 25% and 58.1% of their initial area respectively. The surveys identified four types of cocoa farms, of which 65% of the plots were created between 2002 and 2014. Facing this relatively recent expansion, the issue of the sustainability of cocoa production systems in this region arises. Their agronomic and economic performances and their value for biodiversity conservation should be analyzed in future studies.

  1. La Cour européenne des droits de l’homme et la défense du mode de vie tsigane : Le choix de l’immobilisme. Observations sous Chapman c. Royaume-Uni, 18 janvier 2001

    Ringelheim, Julie

    2001-01-01

    Cet article analyse en profondeur l'arrêt de la Cour européenne des droits de l'homme, Chapman c. Royaume-Uni du 18 janvier 2001 qui porte sur le droit des familles tsiganes à vivre en caravane selon leurs traditions.

  2. Analyse of the potential of the high temperature reactor with respect to the use of fissile materials; Analyse des capacites des reacteurs a haute temperature sous l'aspect de l'utilisation des matieres fissiles

    Damian, F

    2001-07-01

    The high temperature reactors fuel is made of micro-particles dispersed in a graphite matrix. This configuration makes it possible to reach high burnup, higher than 700 GWj/t. Thanks to the decoupling between the thermal and the neutronic behaviors in the core many types of fuels can be used. These characteristics give to HTR reactor very good capacities to burn fissile materials. This work was done in the frame of the evaluation of HTR capacities to enhance the value of the plutonium stocks. These stocks are currently composed of the irradiated fuels discharged from classical PWR or the dismantling of the nuclear weapons and represent a significant energy potential. These studies concluded that high cycles length can be reached whatever the plutonium quality is (from 50 % to 94 % of fissile plutonium). In addition, it was demonstrated that the moderator temperature coefficient becomes locally positive for highly burn fuel while the core global moderator temperature coefficient remained negative in the operation range of the reactor. A significant share of this work was first devoted to the setting of a modeling of the fuel element but also of the reactor's core with the codes of system SAPHYR. The whole of modeling was validated by reference calculations. This work of code assessment is justified by a preliminary work that showed that the classical calculation scheme used for PWR could not be transposed directly to HTR core. (author)

  3. Study of potential of nuclear waste transmutation and safety characteristics of an hybrid system: sub critical accelerator reactor; Etude du potentiel de transmutation et des caracteristiques de surete d`un systeme hybride: accelerateur reacteur sous critique

    Tchistiakov, A

    1998-04-01

    The study of potential of nuclear waste transmutation for the new reactor systems - hybrid reactors - was the object of this work. Global review of different projects is presented. The basic physical parameters definitions, as neutron surplus and relative importance of external source neutrons, are introduced and explained. For these parameters, numerical values are obtained. The advantage in neutron surplus of fast system is noted. Equilibrium model and corresponding toxicities of different isotopes nd nuclear cycles are presented. Numerical analysis for equilibrium model converge validation are performed also. The study of neutron consumption by `transmutable` Long-Lived Fission Products (Tc, I and Cs) show the possibility of their incineration in dedicated fast hybrid reactors. Equilibrium model shown the influence of reprocessing losses level to cycle toxicity level. Relations between specific fuel inventories (mass normalised by power unit) for thermal and fast spectra are examined. The differences are relatively small. Finally, few hybrid reactor concepts with different objects were analysed. These studies confirm that in frameworks of certain Nuclear Energy scenarios the fast hybrid systems can reduce significantly the radio-toxicity of fuel cycle. Preliminary analyses of sub-critical reactor behaviour show big potential of this reactor type in `Transient of Power` kind of accident, even if more detailed study is necessary. (author)

  4. Modeling of delayed strains of concrete under biaxial loadings. Application to the reactor containment of nuclear power plants; Modelisation des deformations differees du beton sous sollicitations biaxiales. application aux enceintes de confinement de batiments reacteurs des centrales nucleaires

    Benboudjema, F

    2002-12-15

    The prediction of delayed strains is of crucial importance for durability and long-term serviceability of concrete structures (bridges, containment vessels of nuclear power plants, etc.). Indeed, creep and shrinkage cause cracking, losses of pre-stress and redistribution of stresses, and also, rarely, the ruin of the structure. The objective of this work is to develop numerical tools, able to predict the long-term behavior of concrete structures. Thus, a new hydro mechanical model is developed, including the description of drying, shrinkage, creep and cracking phenomena for concrete as a non-saturated porous medium. The modeling of drying shrinkage is based on an unified approach of creep and shrinkage. Basic and drying creep models are based on relevant chemo-physical mechanisms, which occur at different scales of the cement paste. The basic creep is explicitly related to the micro-diffusion of the adsorbed water between inter-hydrates and intra-hydrates and the capillary pores, and the sliding of the C-S-H gel at the nano-porosity level. The drying creep is induced by the micro-diffusion of the adsorbed water at different scales of the porosity, under the simultaneous effects of drying and mechanical loadings. Drying shrinkage is, therefore, assumed to result from the elastic and delayed response of the solid skeleton, submitted to both capillary and disjoining pressures. Furthermore, the cracking behavior of concrete is described by an orthotropic elastoplastic damage model. The coupling between all these phenomena is performed by using effective stresses which account for both external applied stresses and pore pressures. This model has been incorporated into a finite element code. The analysis of the long-term behavior is also performed on concrete specimens and prestressed concrete structures submitted to simultaneous drying and mechanical loadings. (author)

  5. Caractéristiques de la croissance et de la production en fruits chez trois variétés de piment (Capsicum annuum L. sous stress salin

    Ibn Maaouia-Houimli, S.

    2011-01-01

    Full Text Available Characteristics of the Growth and Fruits Production of Three Pepper Varieties Capsicum annuum L. under Saline Stress. This work aims to evaluate the salt tolerance of three pepper varieties differing by their precocity: pm797 early variety, beldi semi-early and baklouti late variety. The trials were carried out in pots under glazed greenhouse. The results showed that salinity reduced the growth and production. However, a varietal difference response to salt stress was observed between the studied varieties. Indeed, the varieties beldi and baklouti are characterized by their vigour in absence as in the presence of salt. On the other hand, early variety PM797 is characterized by the stability of production. This is highlighting the utility of early characters in salinity tolerance.

  6. Une variation autour de Vitruve. L’« esthétique architecturante » des milieux curiaux français sous François 1er

    Olivier Deloignon

    2011-05-01

    Full Text Available La métaphore désignant l’architecture comme un langage fait partie des lieux communs du discours renaissant. En France, les origines de cette figure, souvent associée à l’imagerie symbolique des régnants, reposent sur la redécouverte du texte vitruvien à l’aube de la Renaissance. Le premier mouvement est impulsé peu après le retour de l’expédition napolitaine de Charles VIII en 1495, par l’un des « gens de mestier » italiens ramenés à la suite du roi, Fra Giovanni Giocondo. À Paris, Giocondo,...

  7. Amélioration des méthodes de protection anticorrosion des structures métalliques : Sous-sujet : Application des systèmes dits de "maintenance" sur préparation de surface UHP

    MAIRE, G; CENTRE D'ETUDES TECHNIQUES DE L'EQUIPEMENT NORMANDIE-CENTRE - CETE NORMANDIE-CENTRE; LABORATOIRE REGIONAL DES PONTS ET CHAUSSEES DE BLOIS - CETE NORMANDIE-CENTRE - LRPC BLOIS

    2005-01-01

    Le problème actuel de l'entretien de la protection anticorrosion des structures métalliques est l'augmentation du coût découlant des contraintes règlementaires récentes sur l'évacuation et le traitement des déchets. Lors d'un chantier d'entretien, le principal poste générateur de déchets est le décapage. Toutes les solutions techniques permettant de diminuer la quantité et/ou la nocivité des déchets de décapage sont donc intéressantes aussi bien du point de vue économique que de celui de la p...

  8. Fraisage, balayage et mise en oeuvre de la chaussée, transports associés (engins et matériaux) : Consommations et rejets par unité fonctionnelle et par sous-système

    VENTURA, Anne; BEBIEN, Simon; JULLIEN, Agnès; MONERON, Pierre; LABORATOIRE CENTRAL DES PONTS ET CHAUSSEES - LCPC

    2002-01-01

    Cette convention de partenariat LCPC-SETRA-DDE41 s'inscrit en matière de routes et déchets associés, dans le cadre des dispositions législatives de juillet 1992, visant à limiter la mise en décharge dès juillet 2002 au seuls déchets ultimes et ainsi même à favoriser les pratiques de recyclage. Le recyclage si il doit être étendu dans les années futures doit cependant faire l'objet d'études prévisionnelles, notamment environnementales permettant d'optimiser le taux de recyclage dans chaque con...

  9. La couverture forestière et la saisonnalité des précipitations contrôlent l'inflammabilité du sous-bois dans les forêts montagnardes des Alpes

    Fréjaville , T.; Curt , T.; Carcaillet , C.

    2016-01-01

    International audience; Little is known about the understorey flammability of European mountain forests. The aim of this study was to determine the relative effects of climate, vegetation structure and composition on the fuel-driven variation in fire spread and intensity. Fire spread and intensity were simulated under constant moisture and weather conditions for a wide range of understorey fuel parameters measured in the litter, grass and shrub layers. Simulation outputs were used to compare ...

  10. The Muse-4 experiment: measurement of the kinetic parameters of a subcritical system; L'experience MUSE-4: mesure des parametres cinetiques d'un systeme sous-critique

    Vollaire, J

    2004-10-01

    Accelerator Driven Systems (ADS) which are based on an external neutron source coupled to a subcritical core, offer advantages for the incineration of radioactive waste. In order to understand the neutronic specificity of such a system, during the MUSE IV experimental program, the experimental reactor MASURCA (CEA Cadarache) has been coupled to the neutrons source GENEPI. This setup has enabled the development of an on-line measurement technique of the effective multiplication factor. This measurement benefits from the characteristics of the reactor response depending on the multiplication factor at the prompt fission and delayed fission time scales. The analysis of those experiments shows that the proposed method give results in agreement with the one deduced using classical reactivity measurement techniques which can not however be used in a power ADS. (author)

  11. Thermal and hydrodynamic study of a whirling liquid hydrogen layer under high heat flux; Etude thermique et hydrodynamique d'une couche tourbillonnaire d'hydrogenen liquide sous flux de chaleur eleve

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

    1968-03-01

    In order to achieve a cold neutrons source ({lambda} {>=} 4.10{sup -10} m) in a high flux reactor ({approx} 10{sup 15} neutrons/cm{sup 2}.s), a whirling liquid hydrogen layer (145 mm OD, effective thickness 15 mm, height about 180 mm) was formed, out-of-pile, in a cylindrical transparent glass vessel. The whirling motion was obtained by tangential injection of the liquid, near the wall. Thermal and hydrodynamical conditions of formation and laws of similarity of such a layer were studied. The characteristics of this whirling flow were observed as a function of mass flow rate (5 to 27 g/s; 4.3 to 23 l/mn), and of spillway width (18 and 25 mm). Six different nozzles were used : 1.0; 1.5; 1.9; 2.25; 2.65 and 3.0 mm ID. The total heat influx was found between 8.6 and 10.4 kW. The heat flux density was about 9.4 W/cm{sup 2} and the mean layer density around 80 per cent of that of the liquid hydrogen at 20.4 Kelvin. High speed movies were used to analyze the boiling regime. (author) [French] En vue de realiser une source de neutrons froids ({lambda} {>=} 4.10{sup -10} m) dans un reacteur a haut flux ({approx} 10{sup 15} neutrons thermiques/cm{sup 2}.s), on a forme dans un vase cylindrique transparent en verre, hors-pile, une couche tourbillonnaire ('vortex') d'hydrogene liquide (diametre exterieur 145 mm, epaisseur effective 15 mm, hauteur 180 mm environ). Le mouvement giratoire est obtenu par injection tangentielle du liquide pres de la paroi. L'etude porte sur la determination des conditions thermiques et hydrodynamiques de la formation d'une telle couche et sur les regles de similitude de ce phenomene. On a observe les caracteristiques de l'ecoulement giratoire en fonction du debit (de 5 a 27 g/s, soit de 4.3 a 23 1/mn), de la vitesse d'injection (entre 10 et 110 m/s) et de la largeur du deversoir (18 et 25 mm), ceci pour six diametres differents d'injecteur (1.0 ; 1.5; 1.9; 2.25; 2.65 et 3.0 mm). Le flux de chaleur total mesure est compris entre 8.6 et 10.4 kW et la densite de flux de chaleur est de 9.4 W/cm{sup 2} environ. La masse volumique moyenne de la couche est voisine de 80 pour cent de celle de l'hydrogene liquide a 20.4 K. Le cinema rapide a ete utilise pour analyser le regime d'ebullition. (auteur)

  12. Deformation and concentration fluctuations under stretching in a polymer network with free chains. The ``butterfly`` effect; Fluctuations de deformation et de concentration sous etirement dans un reseau polymere contenant des chaines libres. L`effet ``papillon``

    Ramzi, A

    1994-06-01

    Small Angle Neutron Scattering gives access to concentration fluctuations of mobile labeled polymer chains embedded in a polymer network. At rest they appear progressively larger than for random mixing, with increasing ratio. Under uniaxial stretching, they decrease towards ideal mixing along the direction perpendicular to stretching, and can grow strongly along the parallel one, including the zero scattering vector q limit. This gives rise to intensity contours with double-winged patterns, in the shape of the figure `8`, or of `butterfly`. Random crosslinking and end-linking of monodisperse chains have both been studied. The strength of the `butterfly` effect increases with the molecular weight of the free chains, the crosslinking ratio, the network heterogeneity, and the elongation ratio. Eventually, the signal collapses on an `asymptotic` function I(q), of increasing correlation length with the elongation ratio. Deformation appears heterogeneous, maximal for soft areas, where the mobile chains localize preferentially. This could be due to spontaneous fluctuations, or linked to frozen fluctuations of the crosslink density. However, disagreement with the corresponding theoretical expressions makes it necessary to account for the spatial correlations of crosslink density, and their progressive unscreening as displayed by the asymptotic behavior. Networks containing pending labeled chains and free labeled stars lead to more precise understanding of the diffusion of free species and the heterogeneity of the deformation. It seems that the latter occurs even without diffusion for heterogeneous enough networks. In extreme cases (of the crosslinking parameters), the spatial correlations display on apparent fractal behavior, of dimensions 2 to 2.5, which is discussed here in terms of random clusters. 200 refs., 95 figs., 21 tabs., 10 appends.

  13. Development of ODS ferritic-martensitic steels for application to high temperature and irradiation environment; Developpement d'une nouvelle nuance martensitique ODS pour utilisation sous rayonnement a haute temperature

    Lambard, V

    2000-07-01

    Iron oxide dispersion strengthened alloys are candidate for nuclear fuel cladding. Therefore, it is crucial to control their microstructure in order to optimise their mechanical properties at temperatures up to 700 deg C. The industrial candidates, ODS ferritic alloys, present an anisotropic microstructure which induces a weakening of mechanical properties in transversal direction as well as the precipitation of brittle phases under thermal aging and irradiation. For this purpose, we tried to develop a material with isotropic properties. We studied several 9Cr-1Mo ferritic/martensitic alloys, strengthened or not by oxide dispersion. The mechanical alloying was performed by attribution and powders were consolidated by hot extrusion. In this work, different metallurgical characterisation techniques and modelling were used to optimise a new martensitic ODS alloy. Microstructural and chemical characterization of matrix has been done. The effect of austenitizing and isochronal tempering treatments on microstructure and hardness has been studied. Oxide distribution, size and chemical composition have been studied before and after high temperature thermal treatment. The study of phase transformation upon heating has permitted the extrapolation to the equilibrium temperature formation of austenite. Phase transformation diagrams upon cooling have been determined and the transformation kinetics have been linked to austenite grain size by a simple relation. Fine grain size is unfavourable for the targeted application, so a particular thermal treatment inducing a coarser grain structure has been developed. Finally, tensile properties have been determined for the different microstructures. (author)

  14. ALIBABA, an assistance system for the detection of confinement leaks in a PWR reactor; ALIBABA, un systeme d`aide a la detection des voies de fuites du confinement sur un reacteur a eau sous pression

    Bedier, P.O.; Libmann, M. [CEA Centre d`Etudes de Saclay, 91 - Gif-sur-Yvette (France). Dept. de Mecanique et de Technologie

    1995-12-31

    The objective of the Crisis Technical Center (CTC) of the French Institute for Nuclear Protection and Safety (IPSN) is to estimates the consequences of a given nuclear accident on the populations and the environment. ALIBABA is a data processing tool available at the CTC and devoted to the detection of confinement leaks in 900 MWe PWR reactors using the activity values measured by the captors of the installation. The heart of this expert system is a structural and functional representation of the different components directly involved in the leak detection (isolating valves, ventilation systems, electric boards etc..). This tool can manage the availability of each component to make qualitative and quantitative balance-sheets. This paper presents the ALIBABA software, an industrial prototype realized with the SPIRAL knowledge base systems generator at the CEA Reactor Studies and Applied Mathematics Service (SERMA) and commercialized by CRIL-Ingenierie Society. It describes the techniques used for the modeling of PWR systems and for the visualization of the survey. The functionality of the man-machine interface is discussed and the means used for the validation of the software are summarized. (J.S.). 6 refs.

  15. Advanced glycation end products, physico-chemical and sensory characteristics of cooked lamb loins affected by cooking method and addition of flavour precursors

    Roldan, Mar; Loebner, Jürgen; Degen, Julia

    2015-01-01

    The influence of the addition of a flavour enhancer solution (FES) (d-glucose, d-ribose, l-cysteine and thiamin) and of sous-vide cooking or roasting on moisture, cooking loss, instrumental colour, sensory characteristics and formation of Maillard reaction (MR) compounds in lamb loins was studied....... FES reduced cooking loss and increased water content in sous-vide samples. FES and cooking method showed a marked effect on browning development, both on the meat surface and within. FES led to tougher and chewier texture in sous-vide cooked lamb, and enhanced flavour scores of sous-vide samples more...

  16. Patterns of Lethality and Absorbed Dose Distributions in Mice for Monoenergetic Neutrons; Letalite et Distribution de la Dose Absorbee chez la Souris pour des Neutrons Monoenergetiques; Letal'nost' i raspredelenie pogloshchennoj dozy pri obluchenii myshej monoehnergeticheskimi neitronami; Letalidad y Distribucion de las Dosis Absorbidas por el Raton para Neutrones Monoenergeticos

    Frigerio, N. A.; Jordan, D. L. [Argonne National Laboratory, Argonne, IL (United States)

    1964-03-15

    gamma and epithermal contaminations, produce the early ''intestinal death'' almost exclusively. (author) [French] La presence de fortes resonances de C, N et O dans la region du spectre situee entre 100 et 1500 keV a permis d'etudier les interactions specifiques neutrons-nucleides d'apres-la letalite, les valeurs maxima de l'EBR, etc. Grace a la reaction {sup 7}Li(p, n){sup 7}Be, on a produit des neutrons monoenergetiques avec des protons de 62 {mu}A resolus a leur sortie d*une machine van de Graaf et dont l'energie allait de 1882 a 2738 keV. Des souris femelles vierges CF-1, placees dans des capsules en celluloide, ont ete exposees aux neutrons monoenergetiques, a des distances de 3,1 a 11,3 cm de la source, sous des angles de 0 a 1 radian. On les a exposees bilateralement, au cours d*un deplacement sur une orbite, circulaire ou elliptique, normale a l'axe du faisceau. On pouvait ainsi controler la distribution de la dose dans le corps de l'animal. On a procede a des mesures absolues du flux avec des compteurs a fission a {sup 235}U et par comptage absolu a l'aide de fils et de feuilles d'or actives a revetement de cadmium. On a mesure les doses absorbees a l'aide de chambres a ionisation et d'un dosimetre a FeSO{sub 4}-NH{sub 4}SCN de haute sensibilite, tout specialement etudie a cette fin. On a procede ensuite a des mesures relatives de la dose avec des compteurs de Hurst a gaz et protons de recul et avec des scintillateurs a {sup 10}B, {sup 6}Li et protons de recul. Les energies des neutrons ont ete mesurees avec des spectrometres speciaux a {sup 10}B, {sup 3}H, {sup 6}Li et semi-conducteurs. On a mesure l'action des rayons gamma avec des chamb rescompteuis a Ne/Ar. Ces mesures ont montre que les rayons gamma constituent moins de 0,8% et les neutrons thermo-epithermiques moins de 0 ,01% de la dose totale exprimee en rad. Les animaux ont ete exposes a des doses moyennes dans l'axe median de 180 a 1200 rad, les energies des neutrons s' echelonnant de 396 a 658 ke

  17. Flore vasculaire rare et endemique de la peninsule de l'Edough ...

    sous le nom de« biodiversity hotspots» [2]. La flore du bassin mediterraneen est aujourd'hui tres serieusement menacee, en raison de la forte regression des milieux naturels sous l' action de l 'homme, mais aussi parce que cette region serait l'une des plus exposees aux changements climatiques globaux [3-5]. Cette flore ...

  18. Administrateur du système (h/f) | CRDI - Centre de recherches pour ...

    Sous la supervision du gestionnaire, Infrastructure, sécurité et documents (ISD), ... et de la maintenance courants des divers systèmes d'infrastructure du Centre, ... techniques dans les régions et des techniciens sous contrat) pour fournir des ...

  19. Spécialiste de la sécurité en matière de TI (h/f) | CRDI - Centre de ...

    Sous la supervision du gestionnaire, Infrastructure, sécurité et documents (ISD), ... techniques dans les régions et des techniciens sous contrat) pour fournir des ... et à la maintenance des éléments d'infrastructure, en surveillant les travaux ...

  20. Analyste de systèmes intermédiaire (h/f) | CRDI - Centre de ...

    L'analyste de systèmes intermédiaire travaille sous la supervision du ... à la mise en œuvre et à la maintenance d'un large éventail de systèmes tout en assurant ... directement les consultants externes sous contrat afin de faciliter la transition ...

  1. 1957-IJBCS-Article-Koura Kourouma

    hp

    des sous-populations de Parkia biglobosa (néré) du Nord-Bénin, en vue d'une gestion durable de l'espèce. ... Mots clés : Sous-population, Parkia biglobosa, phénotype, structure, Nord-Bénin. ...... nutrition et alimentation dans les pays en.

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

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

  3. THE PHENOMENON OF UNDERSPECIFICATION IN EARLY CHILD GRAMMAR: THE EXAMPLE OF VERB PLACEMENT AND OPTIONALITY / LE PHÉNOMÈNE DE SOUS-SPÉCIFICATION DANS LA GRAMMAIRE ENFANTINE: L'EXEMPLE DU POSITIONNEMENT DU VERBE ET DE L'OPTIONNALITÉ / FENOMENUL FORMULĂRII INEXACTE ÎN GRAMATICA TIMPURIE A COPILULUI: EXEMPLUL PLASĂRII VERBULUI ŞI OPŢIONALITATEA

    Sonja Kitanovska-Kimovska

    2013-11-01

    Full Text Available The aim of this paper is to discuss the phenomenon of underspecification in early child grammar with respect to the syntactic consequences it has in the child language system. The paper addresses the phenomena of verb placement and optionality and how they are accounted for by first language acquisition theories assuming identity between child and adult grammatical systems. These phenomena are discussed within the weak and strong continuity frameworks which account for L1A by incorporating the notion of underspecification among their basic assumptions. Continuity approaches to L1A find underspecification to be of crucial importance in the early grammar. It seems that underspecification of functional categories and their features is what makes the child and adult systems different by provoking a number of syntactic consequences evident in the child system, while absent in the adult one

  4. A study of the diffusion mechanisms in amorphous metallic alloys: diffusion and diffusion under high pressure in an amorphous NiZr alloy; Contribution a l`etude des mecanismes de transport dans les materiaux metalliques amorphes: diffusion et diffusion sous pression dans NiZr amorphe

    Grandjean, A.

    1996-03-01

    The aim of this work is a better understanding of the diffusion mechanism in amorphous metallic alloys. Then interdiffusion and hafnium diffusion in amorphous NiZr alloy have been studied. Samples used are made by sputtering co-deposition under vacuum and are well relaxed before the diffusion measurements. The time evolution of resistivity during annealing due to the decay of a composition modulated film has been measured and from this change in resistivity interdiffusion coefficients have been determined. Dependence of Hf diffusion on temperature and pressure has been studied using (SIMS). In this two cases, the diffusion process obeys an Arrhenius law and gives an activation energy of 1.33 eV for interdiffusion, and 0.76 eV for Hf diffusion. An effect of pressure on Hf diffusion has been found leading to an activation volume of 8.5 angstrom{sup 3}. Thanks to these results, two approaches of the diffusion mechanisms in these systems have been proposed. The first comes from a comparison with the diffusion mechanisms in crystalline metals, that is to say by point defects. The second is an hypothesis of collective motions in these non crystalline alloys. (author).

  5. Stress corrosion of austenitic steels mono and polycrystals in Mg Cl{sub 2} medium: micro fractography and study of behaviour improvements; Corrosion sous contrainte de mono et polycristaux d`aciers inoxydables austenitiques en milieu MgCI{sub 2}: analyse microfractographique et recherche d`ameliorations du comportement

    Chambreuil-Paret, A

    1997-09-19

    The austenitic steels in a hot chlorinated medium present a rupture which is macroscopically fragile, discontinuous and formed with crystallographic facets. The interpretation of these facies crystallographic character is a key for the understanding of the stress corrosion damages. The first aim of this work is then to study into details the micro fractography of 316 L steels mono and polycrystals. Two types of rupture are observed: a very fragile rupture which stresses on the possibility of the interatomic bonds weakening by the corrosive medium Mg Cl{sub 2} and a discontinuous rupture (at the micron scale) on the sliding planes which is in good agreement with the corrosion enhanced plasticity model. The second aim of this work is to search for controlling the stress corrosion by the mean of a pre-strain hardening. Two types of pre-strain hardening have been tested. A pre-strain hardening with a monotonic strain is negative. Indeed, the first cracks starts very early and the cracks propagation velocity is increased. This is explained by the corrosion enhanced plasticity model through the intensifying of the local corrosion-deformation interactions. On the other hand, a cyclic pre-strain hardening is particularly favourable. The first micro strains starts later and the strain on breaking point levels are increased. The delay of the starting of the first strains is explained by a surface distortion structure which is very homogeneous. At last, the dislocations structure created in fatigue at saturation is a planar structure of low energy which reduces the corrosion-deformation interactions, source of micro strains. (O.M.) 139 refs.

  6. Experimental study of chemical-mechanical coupling during percolation of reactive fluid through rocks under stress, in the context of the CO{sub 2} geological sequestration; Etude experimentale du couplage chimie-mecanique lors de la percolation d'un fluide reactif dans des roches sous contrainte, dans le contexte de la sequestration geologique du CO{sub 2}

    Le Guen, Y

    2006-10-15

    CO{sub 2} injection into geological repositories will induce chemical and mechanical instabilities. The study of these instabilities is based on experimental deformation of natural rock samples under stress, in the presence of fluids containing, or not, dissolved CO{sub 2}. Triaxial cells used for the experiments permitted an independent control and measurement of stress, temperature, fluid pressure and composition. Vertical strains were measured during several months, with a resolution of 1.10{sup -12} s{sup -1} on the strain rate. Simultaneously, fluids were analysed in order to quantify fluid-rock interactions. For limestone samples, percolation of CO{sub 2}-rich fluids increases strain rate by a factor 1.7 up to 5; on the other hand, sandstone deformation remained almost the same. Increase in strain rate with limestone samples was explained by injected water acidification by the CO{sub 2} which increases rock solubility and reaction kinetics. On the opposite, small effect of CO{sub 2} on quartz explains the absence of deformation. X-ray observations confirmed the importance of rock composition and structure on the porosity evolution. Numerical simulations of rock elastic properties showed increasing shear stress into the sample. Measured deformation showed an evolution of reservoir rocks mechanical properties. It was interpreted as the consequence of pressure solution mechanisms both at grains contacts and on grain free surfaces. (author)

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

    Gressier, F.

    2008-11-15

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

  8. Structure analysis of low velocity reactive flows on a flat plate: the case of the laminar diffusion flame in a low gravity environment; Analyse de la structure des ecoulements reactifs a faible vitesse sur une plaque plane: cas de la flamme de diffusion laminaire sous un environnement de gravite reduite

    Joulain, P.

    2003-09-01

    The combustion of a flat plate in a boundary layer under microgravity conditions, which was first described by Emmons, is studied using a gaseous burner. Magnitude of injection and blowing velocities are chosen to be characteristic of pyrolyzing velocity of solid fuels and of ventilation systems in space stations. These velocities are about 10 cm/s for oxidizer flow and 0.4 cm/s for fuel flow. In this configuration, flame layout results from a coupled interaction between oxidizer flow, fuel flow and thermal expansion. Influences of these parameters are studied by means of flame length and standoff distance measurements using CH* chemiluminescence's and visible emission of the flame. Flow was also studied with Particle Image Velocimetry (PIV). At first with inert flows, with and without injection to identify burner effects on it, and then with a reacting flow in a microgravity environment. Thermal expansion effects have been shown by means of the acceleration of oxidizer flow. Three dimensional effects, which are strongly marked for high injection velocities did not were studied, but three dimensional tools adaptability (wavelength and polarizing coding laser tomography) to parabolic flights particular conditions were investigate. Flame sensitivity to g-jitters was studied using a local modified Richardson number introduced by Torero and g-jitters effect on flame were investigated according to g-jitters frequency and range involved by parabolic flights. (author)

  9. Elaboration by ion implantation of cobalt nano-particles in silica layers and modifications of their properties by electron and swift heavy ion irradiations; Elaboration par implantation ionique de nanoparticules de cobalt dans la silice et modifications de leurs proprietes sous irradiation d'electrons et d'ions de haute energie

    D' Orleans, C

    2003-07-15

    This work aims to investigate the capability of ion irradiations to elaborate magnetic nano-particles in silica layers, and to modify their properties. Co{sup +} ions have been implanted at 160 keV at fluences of 2.10{sup 16}, 5.10{sup 16} and 10{sup 17} at/cm{sup 2}, and at temperatures of 77, 295 and 873 K. The dependence of the particle size on the implantation fluence, and more significantly on the implantation temperature has been shown. TEM (transmission electronic microscopy) observations have shown a mean diameter varying from 1 nm for implantations at 2.10{sup 16} Co{sup +}/cm{sup 2} at 77 K, to 9.7 nm at 10{sup 17} Co{sup +}/cm{sup 2} at 873 K. For high temperature implantations, two regions of particles appear. Simulations based on a kinetic 3-dimensional lattice Monte Carlo method reproduce quantitatively the features observed for implantations. Thermal treatments induce the ripening of the particles. Electron irradiations at 873 K induce an important increase in mean particle sizes. Swift heavy ion irradiations also induce the ripening of the particles for low fluences, and an elongation of the particles in the incident beam direction for high fluences, resulting in a magnetic anisotropy. Mechanisms invoked in thermal spike model could also explain this anisotropic growth. (author)

  10. Contribution to multi-agents modeling of the operation of industrial processes: application to the operation of a pressurized water reactor under accidental situation; Contribution a la modelisation multi-agents de la conduite de processus industriels: application a la conduite en situation accidentelle d`un reacteur nucleaire a eau sous pression

    Elias, P.

    1996-11-13

    This work is related to the CEA `Escrime` project which concerns the reliability and functioning safety of nuclear reactors, and in particular the operation and supervision of nuclear installations. Its aim is the analysis and the formalizing of PWRs operation in order to define the collaboration and optimum sharing of tasks between human operators and automatized systems for an improved functioning safety. Chapter 1 describes the operation of nuclear reactors and the instrumentation and control activities. It focusses on the weaknesses of actual automatized systems and examines the interest of the multi-agents approach to build an improved automatized system. Chapter 2 presents the actual state of the art about multi-agent systems and about their application to reactor operation. Chapter 3 is devoted to the definition of the conceptual model of automatized systems developed in this work (distribution of operation activities, competition between agents, hierarchy, arbitration). Chapter 4 describes the computer model of the essential operating system elaborated according to the conceptual model defined above. Modeling is performed using Spirit and an application is described in chapter 5. (J.S.). 58 refs.

  11. The deep cerebral stimulation of the under thalamic nucleus modifies the cerebral metabolism in {sup 18}FDG-Tep of obsessive compulsive patients; La stimulation cerebrale profonde du noyau sous thalamique modifie le metabolisme cerebral en 18FDG-TEP des patients obsessionnels compulsifs

    Le Jeune, F.; Garin, E. [Service de medecine nucleaire, centre Eugene-Marquis, Rennes, (France); Verin, M.; Peron, J. [service de neurologie, CHU Pontchaillou, Rennes, (France); Mallet, L.; Yelnik, J. [Inserm, Avenir Team, Behavior, Emotion and Basal Ganglia, IFR 70, Pitie-Salpetriere, Paris, (France); Kreps, M.O. [Inserm U796, service de psychiatrie, hopital Sainte-Anne, Paris, (France); Drapier, D.; Millet, B. [service de psychiatrie adulte, centre hospitalier Guillaume-Regnier, Rennes, (France)

    2009-05-15

    The aim of this work was to find again this orbito-frontal hyper metabolism among the resistant obsessive compulsive disorder patients that are going to benefit of a deep cerebral stimulation of the under thalamus nucleus and to demonstrate that this new therapy approach leads a reduction of the metabolism in this area in correlation with the clinical improvement. It is about the first study realized in isotopic functional imaging on ten resistant compulsive disorder patients treated by bilateral deep cerebral stimulation of the under thalamus nucleus. It shows that the treatment efficiency is in relation with a reduction of the glucide metabolism in the right orbito-frontal cortex. It suggests equally that the under thalamus nucleus would be functionally linked to the orbito-frontal cortex. (N.C.)

  12. Pratique cacaoyère, délitement de l'accès au foncier et sécurité alimentaire dans la sous-préfecture de Dania (centre-ouest de la Côte d'Ivoire

    Koffi, GRY.

    2018-01-01

    Full Text Available Cocoa Cultivation, Disintegration of Land Access and Food Security in the Sub-prefecture of Dania (Center-west of Côte d'Ivoire. The cocoa plantations are exponentially increasing and most of the rural households in the forest area of Ivory Coast are involved in it. In the sub-prefecture of Dania, 77.7% of the households have a cocoa exploitation. Currently, the cocoa plantations in the area of Dania are facing a production crisis which is amplified by the military political crisis of September 2002. The incomes of the producers of cocoa are decreasing. Because of the great impact of the cocoa production on farm land, the available area to fulfill the food needs becomes insufficient. Forty three percent of the households lack sufficient land to satisfy their food production. The minimum period of seven year of fallow being no longer respected soil fertility problems are created and consequently a decrease of the agricultural yields. Fifty seven percent of the households are facing food insecurity. Therefore, the households have elaborated new strategies for land appropriation, such as the borrowing of farm land (13 %, the increased use of the phytosanitary products (52% and particularly the higher attraction for the exploitation of fallow land (40%.

  13. Ion transport under the effect of an electric field in porous medium: application to the separation of rare earths by focalization electrophoresis; Transport d'ions sous l'effet d'un champ electrique en milieu poreux: Application a la separation de terres rares par electrophorese a focalisation

    Vieira-Nunes, A.I

    1999-01-15

    Trivalent ions of rare earth elements have very similar properties and their difficult separation each from another is usually carried out by liquid-liquid extraction or ion exchange. Focalization electrophoresis represents an alternative route to the usual techniques. The purpose of this work consisted of the fundamental investigation of ion transport phenomena in electrophoretic processes. Focalization electrophoresis is suitable for separation of amphoteric species such as rare earth ions, using a pH gradient in the cell and upon addition of a complexed agent e. g. EDTA. This technique relies upon the difference in iso-electrical points of the considered species, being under the form of free cation near the anode, and in the form of anionic complexed species closer to the cathode. Rare earth species are submitted to the antagonist effects of diffusion and migration, enabling their focalization to occur at the iso-electrical point, corresponding to nil value of their effective mobility. Following a literature survey on rare earth elements and electrophoresis processes, the document describes theoretical and experimental investigations of complexation equilibria of some rare earth elements, namely lanthanum, neodymium, praseodymium and cerium, depending on pH. Values for the iso-electrical points could be estimated. Transport and focalization phenomena in view of rare earth separation, are dealt in the last chapter. Investigations were first carried out without forced circulation of the electrolyte solution and the transient behavior of the system allowed operating conditions to be design and built-up of a continuous device, more suitable to separation, and provided with 42 potential and 42 temperature sensors: the results of the preliminary runs, in form of variable profiles, are presented and discussed. (author)

  14. RTE results 2002: positive net income (+112 million euros), in keeping with forecasts, at the end of a year placed under the sign of quality; Bilan RTE 2002: un resultat net positif (+112 M d'euros), conforme aux previsions, au terme d'une annee placee sous le signe de la qualite

    NONE

    2003-03-01

    The results of RTE, the French Transmission System Operator, confirm the company's sound financial position at the end of a year placed under the sign of quality. RTE announces a net income after taxes for 2002 that is in keeping with its forecasts: +112 million euros (versus 250 million euros in 2001) for 3,657 million euros in sales revenue. 616 million euros were devoted to investments for the development and replacement of the company's transmission and interconnection networks. RTE also continued the reduction of its debt by 99 million euros. The year 2001 had experienced a cold spell at year-end, bringing with it higher-than-average revenue (+80 million euros). 2002, which was exceptionally mild at the end of the year, saw revenue fall off by 40 million euros compared with a normal year. In all, the climatic impact goes to explain a drop of 120 million euros in 2002. This drop is partially offset by additional revenue since the adoption on 1/11/02 of the network access tariff (about 30 million euros). This tariff is now substituted for the transitional price scale which was unfavourable to RTE. Operating expenses rose from 3,089 million euros to 3,316 million euros. The most significant increases are to be attributed in particular to: - the contribution of 68 million euros to the 'ETSO Fund', ETSO being the Association of European Transmission System Operators which, since 1/03/02, has ensured the compensation for network utilisation costs related to international transfers, - the gaining in momentum, with more than 80 million euros, of the network mechanical security enhancement programme decided in the wake of the storms of 1999, which aims at adapting RTE infrastructures to the new technical requirements for wind resistance. More than 720 km of power lines were erected or replaced while 12 electrical substations were connected to the RTE network in 2002. Among these projects, mention should be made of the following: the commissioning of the first French 400 kV transformer -phase shifter at La Praz (Savoie); the reconstruction of the 400 kV interconnection line linking Vigy (France) to Uchtelfangen (Germany), - Completion of the 400 kV line which connects Tavel to Tricastin. As regards services, the offer developed particularly through: base load energy block exchange notifications; the extension of the Non-guaranteed Limited Exceeding of Subscribed Demand service; the continuation between France and Great Britain of the allocation of exchange capacity, in both directions, by means of auctions; a daily allocation of capacity between France and Italy. The year 2002 was that of the total involvement of RTE in the quality approach. All of RTE's operational units and central entities have been certified ISO 9001 V 2000 since 27/12/02. RTE is readying itself in 2003 to obtain the overall certification for the company. At the same time, RTE obtained the ISO 14001 environmental certification for the entire company in 2002. It buried nearly 25% of new high voltage lines and removed 161 km of the existing network. The efforts deployed by RTE and its employees have helped increase customer satisfaction. This is the main conclusion of the survey of 400 customers conducted in 2002, which highlights a customer satisfaction rate close to 90%.

  15. Wind farm project on the territory of municipalities of Equennes-Eramecourt, Saulchoy-sous-Poix, Thieulloy-la-Ville (80). Non technical summary of the exploitation authorisation request file. Opinion of the authority for the environment on the impact study and hazard study. Public inquiry report

    Lignier, Jean-Pierre; Gourio, Yann

    2016-01-01

    A first report recalls some general data about wind energy development, exploitation (in the world, Europe and France) and interest. It presents the project which is to be built (installation characteristics, location, wind turbine description, wind turbine safety systems), the requester and its financial and technical capacities, and the authorisation request file. Next parts proposes a brief presentation of the studied area, a description of the initial environment in terms of hydro-geological, hydraulic and hydrographic, and natural environment, cultural heritage, soil use, town planning issues, activities, natural and technological risks, and landscape issues. It proposes an assessment of the potential impact of the project on the environment, evokes substitution solutions, addresses the compliance with planning documents, analyses and characterises potential hazards. The next document states the opinion of the authority of the environment. It presents the project and its context (with its environmental, physical, urban, landscape, and legal aspects); states the opinion on the content of the impact study and hazard study. The last report concerns the public inquiry. It contains some generalities about the legal frameworks and the project, a report of the inquiry organisation and procedure (decrees, modalities, meetings and visits, public information, noticed incidents, general atmosphere), and then the statement of the inquiry commissioner on the various aspects of the project

  16. Search for low energy quasi-vertical muons with an underwater cosmic neutrino detector, environmental study of the detector setting; Recherche de muons quasi verticaux de basse energie a l'aide d'un detecteur de neutrinos cosmiques sous-marin et etude environnementale de son site d'installation

    Blondeau, F. [CEA/Saclay, Dept. d' Astrophysique, de la Physique des Particules, de la Physique Nucleaire et de l' Instrumentation Associee (DAPNIA), 91 - Gif-sur-Yvette (France)]|[Paris-7 Univ., 75 (France)

    1999-06-01

    The European collaboration named ANTARES aims at operating a large submarine neutrino telescope. Mooring lines make up this detector. Each is about four hundred metres high and equipped with photomultiplier tubes. These tubes record the Cherenkov light emitted by muons resulting from the interaction of neutrinos with matter. It was chosen to install the telescope in the Mediterranean, off the shore of Toulon, by a depth of twenty-three hundred metres. One chapter of this dissertation is devoted to the environment parameters of this site: amount of natural light, fouling of glass elements and water transparency is reviewed. Such a disposal is originally designed to look for possible astronomic neutrino sources emitting neutrinos, thus being complementary with the study of our Universe relying on gamma rays. It is shown in this dissertation that two other current riddles in physics can be investigated by ANTARES, when a specific analysis is taken into account: what is the mass of the neutrinos on the one hand (via the phenomenon called neutrino oscillations), and in the other hand the evidence for a new particle which could participate to the nature of the dark matter in the Universe. This analysis is based upon the detection of nearly vertical muons (zenith angle less than fifteen degrees), with an energy lower than 100 GeV. (author)

  17. TEM characterisation of stress corrosion cracks in nickel based alloys: effect of chromium content and chemistry of environment; Caracterisation par MET de fissures de corrosion sous contrainte d'alliages a base de nickel: influence de la teneur en chrome et de la chimie du milieu

    Delabrouille, F

    2004-11-15

    Stress corrosion cracking (SCC) is a damaging mode of alloys used in pressurized water reactors, particularly of nickel based alloys constituting the vapour generator tubes. Cracks appear on both primary and secondary sides of the tubes, and more frequently in locations where the environment is not well defined. SCC sensitivity of nickel based alloys depends of their chromium content, which lead to the replacement of alloy 600 (15 % Cr) by alloy 690 (30 % Cr) but this phenomenon is not yet very well understood. The goal of this thesis is two fold: i) observe the effect of chromium content on corrosion and ii) characterize the effect of environment on the damaging process of GV tubes. For this purpose, one industrial tube and several synthetic alloys - with controlled chromium content - have been studied. Various characterisation techniques were used to study the corrosion products on the surface and within the SCC cracks: SIMS; TEM - FEG: thin foil preparation, HAADF, EELS, EDX. The effect of chromium content and surface preparation on the generalised corrosion was evidenced for synthetic alloys. Moreover, we observed the penetration of oxygen along triple junctions of grain boundaries few micrometers under the free surface. SCC tests show the positive effect of chromium for contents varying from 5 to 30 % wt. Plastic deformation induces a modification of the structure, and thus of the protective character, of the internal chromium rich oxide layer. SCC cracks which developed in different chemical environments were characterised by TEM. The oxides which are formed within the cracks are different from what is observed on the free surface, which reveals a modification of medium and electrochemical conditions in the crack. Finally we were able to evidence some structural characteristics of the corrosion products (in the cracks and on the surface) which turn to be a signature of the chemical environment. (author)

  18. Contribution to the understanding of the behaviour of reinforced concrete shear walls under seismic loading: contribution of experiment and modeling to the design; Contribution a la comprehension du fonctionnement des voiles en beton arme sous sollicitation sismique: apport de l'experimentation et de la modelisation a la conception

    Ile, N

    2000-12-01

    This thesis deals with aspects of seismic behaviour of reinforced concrete shear walls (RCSW). Its objective is to introduce a useful modelling approach for addressing the non-linear response of a large variety of RCSW and to identify several aspects in which this numerical approach could be implemented into design applications. Firstly, the characteristics of the behaviour of RCSW under seismic loading, some design principles and different modelling approaches are discussed. As an important lack of knowledge in several fields was identified, it was considered that three types of shear walls deserve more attention: slightly reinforced slender walls; U-shaped walls and heavily reinforced squat shear walls. A local modelling approach is adopted and the material constitutive models are described in details. Secondly, the behaviour of the two mock-up, CAMUS I and II, tested on the shaking-table during the CAMUS programme, which are slightly reinforced and designed according to the French code PS92 is simulated using a 2-D finite element model (FEM). For comparison purposes, the case of the CAMUS III mock-up, designed according to EC8, is considered. We are then dealing with the case of U-shaped walls under dynamic and cyclic loading. The results obtained from numerical simulations, based on a 3-D shell FEM, are compared with those obtained from tests carried out in the frame of the ICONS programme. Finally, the numerical model is applied to the case of heavily reinforced squat shear walls (similar to those used in the nuclear power plant buildings) subjected to shear loading. A 2-D FEM is considered in order to simulate the behaviour of three different walls, which were tested pseudo-dynamically during the SAFE programme. The results from both experimental and numerical studies are compared and discussed. The most important factors affecting the behaviour of RCSW are highlighted. Different examples of possible contributions to design are presented. (author)

  19. Report of the National Sub-Committee to the Interprovincial Standards Program Coordinating Committee on the Interprovincial Computerized Examination Management System=Rapport du Sous-Comite National presente au Comite de Coordination du Programme de Normes Interprovincials sur le systeme de gestion des examens informatises interprovinciaux.

    New Brunswick Dept. of Advanced Education and Training, Fredericton. Interprovincial Standards Program Coordinating Committee.

    In January 1985, Employment and Immigration Canada funded a pilot project in New Brunswick for the development and testing of an Interprovincial Computerized Examination Management (ICEM) System. The resulting system is comprised of a dual interprovincial and provincial item bank facility, a software component offering the option of computerized…

  20. Les filles de l’eau. Une histoire des femmes et de la natation en France (1905-1939), thèse de doctorat en histoire contemporaine sous la direction de Christine Bard, Université d’Angers, 2010

    Velez, Anne

    2011-01-01

    En étudiant l’histoire des femmes à travers le prisme d’une pratique sportive, en l’occurrence la natation, j’ai souhaité faire émerger la visibilité des femmes dans ce sport, donner un passé aux femmes, mais aussi ne pas négliger les rapports sociaux de sexes ainsi que la construction culturelle de la différence des sexes. Au regard de l’étude historiographique du sujet, il convenait donc de (ré)interroger l’histoire des femmes à travers la natation et de répondre avec force et détails à de ...