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Sample records for belleville sur loire-2 reactor

  1. Belleville rouge, Belleville noir, Belleville rose: The Complex Identity of a Parisian quartier

    Directory of Open Access Journals (Sweden)

    Carolyn Stott

    2015-03-01

    Full Text Available The Parisian quartier of Belleville has long been the subject of scholarly literature and popular culture due to its colourful history and diverse population. Its symbolic boundaries extend beyond the geographical limits imposed by its administrative demarcation. Myths abound as to the extent of its rebellious past, its contemporary image as a melting pot and its prevalence as a décor for the noir genre. In this article a three-tiered categorisation of Belleville is adopted which corresponds to various representations of the suburb in literature, popular culture and from the perspective of its inhabitants. Belleville rouge reflects the quartier’s revolutionary past and the late 20th century struggle associated with its physical metamorphosis. Belleville noir focusses on the quartier’s criminal face, as it is depicted in Parisian film and roman noir and as it exists in reality. Belleville rose highlights the pleasures of the quartier: its cosmopolitan character whose representation verges at times on utopian.    In his Malaussène series (1985-1995, writer and former resident Daniel Pennac portrays Belleville as a unique blend of rouge, noir and rose. This fusion of fairy tale, detective fiction, myth and reality establishes a complex Bellevillois identity distinct from other contemporary representations. The article concludes that it is impossible to associate a single identity with Belleville. The quartier’s contemporary face is inextricably linked to its past, the memory of which is preserved by its inhabitants and by social and literary commentators such as Pennac. In keeping with historian Pierre Nora’s concept of cultural memory, Pennac thus assumes the role of guardian of Belleville’s cultural memory in the face of the quartier’s perpetual evolution.

  2. Handbook for the calculation of reactor protections; Formulaire sur le calcul de la protection des reacteurs

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1963-07-01

    This note constitutes the first edition of a Handbook for the calculation of reactor protections. This handbook makes it possible to calculate simply the different neutron and gamma fluxes and consequently, to fix the minimum quantities of materials necessary under general safety conditions both for the personnel and for the installations. It contains a certain amount of nuclear data, calculation methods, and constants corresponding to the present state of our knowledge. (authors) [French] Cette note constitue la premiere edition du 'Formulaire sur le calcul de la protection des reacteurs'. Ce formulaire permet de calculer de facon simple les difterents flux de neutrons et de gamma et, par suite, de fixer les quantites minima de materiaux a utiliser pour que les conditions generales de securite soient respectees, tant pour le personnel que pour les installations. Il contient un certain nombre de donnees nucleaires, de methodes de calcul et de constantes correspondant a l'etat actuel de nos connaissances. (auteurs)

  3. The research reactors their contribution to the reactors physics; Les reacteurs de recherche leur apport sur la physique des reacteurs

    Energy Technology Data Exchange (ETDEWEB)

    Barral, J.C. [Electricite de France (EDF), 75 - Paris (France); Zaetta, A. [CEA/Cadarache, Direction des Reacteurs Nucleaires, DRN, 13 - Saint-Paul-lez-Durance (France); Johner, J. [CEA/Cadarache, Dept. de Recherches sur la Fusion Controlee (DRFC), 13 - Saint Paul lez Durance (France); Mathoniere, G. [CEA/Saclay, DEN, 91 - Gif sur Yvette (France)] [and others

    2000-07-01

    The 19 october 2000, the french society of nuclear energy organized a day on the research reactors. This associated report of the technical session, reactors physics, is presented in two parts. The first part deals with the annual meeting and groups general papers on the pressurized water reactors, the fast neutrons reactors and the fusion reactors industry. The second part presents more technical papers about the research programs, critical models, irradiation reactors (OSIRIS and Jules Horowitz) and computing tools. (A.L.B.)

  4. Public debate on the EPR reactor; Debat public sur le reacteur EPR

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2005-10-15

    In the framework of the new EPR European Pressurized Reactor implementation in France, the public asked the first Ministry on the protection of nuclear matters, transports and installations against the terrorism and the spiteful actions. This document provides information on the subject and shows the safety of the new reactor. (A.L.B.)

  5. Reactors

    CERN Document Server

    International Electrotechnical Commission. Geneva

    1988-01-01

    This standard applies to the following types of reactors: shunt reactors, current-limiting reactors including neutral-earthing reactors, damping reactors, tuning (filter) reactors, earthing transformers (neutral couplers), arc-suppression reactors, smoothing reactors, with the exception of the following reactors: small reactors with a rating generally less than 2 kvar single-phase and 10 kvar three-phase, reactors for special purposes such as high-frequency line traps or reactors mounted on rolling stock.

  6. Superelastic SMA Belleville washers for seismic resisting applications: experimental study and modelling strategy

    Science.gov (United States)

    Fang, Cheng; Zhou, Xiaoyi; Israel Osofero, Adelaja; Shu, Zhan; Corradi, Marco

    2016-10-01

    This study sheds considerable light on the potential of superelastic shape memory alloy Belleville washers for innovative seismic resisting applications. A series of experimental studies were conducted on washers with different stack combinations under varying temperatures and loading scenarios. The washers showed satisfactory self-centring and energy dissipation capacities at room temperature, although slight degradations of the hysteretic responses accompanied by residual deformations were induced. The hysteretic loops became stable after a few number of cycles, indicating good repeatability. The washers also showed good flexibility in terms of load resistance and deformation, which could be easily varied via changes in the stack combination. Compromised self-centring responses were observed at temperatures below 0 °C or above 40 °C, and a numerical study, validated by the experimental results, was adopted to further investigate the deformation mechanism of the washers. A further phenomenological model, taking account of the degradation effects under varied temperatures, was developed to enable effective and accurate simulation of devices incorporating the washers. Good agreements were observed between the test and simulation results, and the model was shown to have good numerical robustness for wide engineering applications.

  7. Shutdown channels and fitted interlocks in atomic reactors; Chaines de securite et verrouillages installes sur les piles atomiques

    Energy Technology Data Exchange (ETDEWEB)

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

    1968-07-01

    This catalogue consists of tables (one per reactor) giving the following information: number and type of detectors, range of the shutdown channels, nature of the associated electronics, thresholds setting off the alarms, fitted interlocks. These cards have been drawn up with a view to an examination of the reactors safety by the 'Reactor Safety Sub-Commission', they take into account the latest decisions. The reactors involved in this review are: Azur, Cabri, Castor-Pollux, Cesar-Marius-2, Edf-2, EL3, EL4, Eole, G1, G2-G3, Harmonie, Isis, Masurca, Melusine, Minerve, Osiris, Pegase, Peggy, PAT, Rapsodie, SENA, Siloe, Siloette, Triton-Nereide, and Ulysse. (authors) [French] Ce catalogue est compose d'un ensemble de tableaux (a raison de un tableau par pile) donnant les renseignements suivants: nombre et nature des detecteurs, dynamique des chaines, nature de l'electronique associee, seuils provoquant des actions de securite, verrouillages installes. Ces fiches ont ete etablies en vue de l'examen de la securite des piles par la 'Sous-Commission de Surete des Piles', et tiennent compte des decisions de celle-ci. Les reacteurs concernes sont: Azur, Cabri, Cator-Pollux, Cesar-Marius-2, Edf-2, EL3, EL4, Eole, G1, G2-G3, Harmonie, Isis, Masurca, Melusine, Minerve, Osiris, Pegase, Peggy, PAT, Rapsodie, SENA, Siloe, Siloette, Triton-Nereide, et Ulysse. (auteurs)

  8. Finite Element Analysis on Belleville Spring in Flanged Joints%法兰接头用碟形弹簧的有限元分析

    Institute of Scientific and Technical Information of China (English)

    王俊和

    2015-01-01

    Normal belleville spring and belleville spring used in flanged joints are simulated through 2-D finite element analysis and the friction effect on the load of the belleville spring used in flanged joints is considered. The results show that the fraction has intense impact on the rigidity of the belleville spring used in flanged joints which is quite significant in the design process.%利用2-D有限元法模拟了普通碟形弹簧和法兰接头用碟形弹簧, 并考虑了摩擦对法兰接头用碟形弹簧承载的影响. 结果表明, 有限元法对碟簧的模拟十分精确. 此外, 摩擦对法兰接头用碟形弹簧的刚度影响较大, 这在设计过程中不容忽视.

  9. Reactor

    Science.gov (United States)

    Evans, Robert M.

    1976-10-05

    1. A neutronic reactor having a moderator, coolant tubes traversing the moderator from an inlet end to an outlet end, bodies of material fissionable by neutrons of thermal energy disposed within the coolant tubes, and means for circulating water through said coolant tubes characterized by the improved construction wherein the coolant tubes are constructed of aluminum having an outer diameter of 1.729 inches and a wall thickness of 0.059 inch, and the means for circulating a liquid coolant through the tubes includes a source of water at a pressure of approximately 350 pounds per square inch connected to the inlet end of the tubes, and said construction including a pressure reducing orifice disposed at the inlet ends of the tubes reducing the pressure of the water by approximately 150 pounds per square inch.

  10. Hanging core support system for a nuclear reactor. [LMFBR

    Science.gov (United States)

    Burelbach, J.P.; Kann, W.J.; Pan, Y.C.; Saiveau, J.G.; Seidensticker, R.W.

    1984-04-26

    For holding the reactor core in the confining reactor vessel, a support is disclosed that is structurally independent of the vessel, that is dimensionally accurate and stable, and that comprises tandem tension linkages that act redundantly of one another to maintain stabilized core support even in the unlikely event of the complete failure of one of the linkages. The core support has a mounting platform for the reactor core, and unitary structure including a flange overlying the top edge of the reactor vessels, and a skirt and box beams between the flange and platform for establishing one of the linkages. A plurality of tension rods connect between the deck closing the reactor vessel and the platform for establishing the redundant linkage. Loaded Belleville springs flexibly hold the tension rods at the deck and separable bayonet-type connections hold the tension rods at the platform.

  11. Research on nuclear energy in the fields of fuel cycle, PWR reactors and LMFBR reactors; Recherche sur l`energie nucleaire dans les domaines du cycle du combustible des reacteurs a eau legere et des reacteurs a neutrons rapides

    Energy Technology Data Exchange (ETDEWEB)

    Barre, B.; Camarcat, N.

    1995-12-31

    In this article we present the CEA research programs to improve the safety of the next generation of reactors, to manage the Plutonium and the wastes of the fuel cycle end and to ameliorate the competitiveness. 6 refs.

  12. The ISRN has stated on the CABRI reactor restarting; L'IRSN a donne son avis sur le redemarrage du reacteur CABRI

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2009-07-01

    This paper presents the different issues examined by the ISRN (the French Institute of Radioprotection and Nuclear Safety) for the restarting of the pool type research CABRI reactor which is briefly described in appendix. These issues are: the design, realisation and monitoring of the new pressurised water test loop, the reassessment of the protection system limiting the reactivity injection during tests, inspection of fuel pencil condition, reassessment of safety studies, inspection of the condition of existing equipment which are essential for safety, reassessment of the seismic risk and of the fire risk, reassessment of operation conditions (personal radioprotection, human and organisational factors). An appendix contains the report by the Permanent Group of Experts for Nuclear Reactors with its recommendations.

  13. New rules for the interventions on the primary circuit of nuclear reactors; Nouvelles regles pour les interventions sur le circuit primaire des reacteurs electronucleaires

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-07-13

    This decision from the French authority of nuclear safety (ASN) concerns the enforcement of new technical rules relative to the maintenance activities performed on the primary circuit of Electricite de France (EdF) reactors. Different levels of intervention are considered: non noticeable interventions internally carried out by EdF with a simple information given to the ASN, noticeable interventions prepared and performed by EdF under the control of the regional directions of industry, research and environment (DRIRE), and important interventions requiring a qualification dossier validated by the bureau of nuclear boilers control (BCCN). The details of the procedure are given in the attached note. (J.S.)

  14. Electric failure on the reactor n.3 of the nuclear power plant of Dampierre; Defaillance electrique sur le reacteur n. 3 de la centrale nucleaire de Dampierre

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2007-05-15

    This note of information resumes the progress of the electric failure on the reactor n.3 of the nuclear power plant of Dampierre, the organization during the incident, it establishes then a comparison with the incident arisen to Forsmark in 2006 and reminds that it lead in an inspection on behalf of the Asn which noticed that all the procedures had been respected by the operators and did not noticed any abnormality in the maintenance. This event was classified at the level 1 of the international nuclear event scale (INES). (N.C.)

  15. Three-Dimensional Numerical Analysis for the Pipe Flanged Jiont with Belleville Spring in Delayed Coking Unit%延迟焦化装置中带碟簧的管法兰接头三维数值分析

    Institute of Scientific and Technical Information of China (English)

    董智; 仇性启; 赵宗彬

    2011-01-01

    FEA was used to analyze the force and deformation of coke tower and the pipe in delayed coking unit. Three - dimensional numerical analysis for the pipe flanged joint with belleville spring was carried on to investigate belleville spring's effects on gasket stress under the elevated temperature condition of coking stage. The results of the simulation show that coke tower produces thermal expansion, so induces the bend deformation of pipeline in the coking stage. High temperature's effects on them are more obvious than the pressure's. Proper use of belleville spring is more favourable for maintaining the working stress of gasket of the pipe flanged joint under the condition of elevated temperature.%应用有限元法分析延迟焦化装置中焦炭塔和管道的受力和变形,并针对生焦高温工况,对带有碟形弹簧的管法兰接头进行三维数值模拟,分析碟形弹簧对垫片应力的影响.模拟结果表明,生焦时焦炭塔受高温膨胀,导致管道弯曲变形,而内压对此影响相对要小很多;高温下选用适当的碟形弹簧,有利于维持管法兰接头的垫片工作应力.

  16. Failure analysis for fatigue fracture of tractor clutch belleville spring%拖拉机离合器碟形弹簧疲劳断裂失效分析

    Institute of Scientific and Technical Information of China (English)

    严正峰; 李盖华; 夏建新

    2014-01-01

    通过对拖拉机碟形弹簧的化学成分、热处理和表面机械强化工艺、硬度、金相分析及强化疲劳试验,发现弹簧脱碳层、硬度和表面机械强化工艺不足是产生弹簧疲劳断裂的主要原因。通过对脱碳层、硬度的控制及挤压圆角、抛丸等表面机械强化工艺的改善,产品性能满足了使用要求。%Based on chemical composition, heat treatment and surface strengthening technology, hardness, metallographic analysis of the tractor belleville spring, combined with the intensifying fatigue test, it was found that the decarburization layer of materials, hardness of belleville spring and insufficient of strengthening technology were the principal causes of fatigue fracture.By the control of the material decarburization layer, the hardness of belleville spring and surface strengthening technology improvement such as rounded corners extrusion and surface shot peening, the product performance can meet the use requirement.

  17. Management of a severe accident on a pressurised water reactor in France; La gestion d'un accident grave sur un reacteur a eau sous pression en France

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2011-07-01

    This brief document defines what a severe accident is on a nuclear reactor, indicates the different failure modes which have been defined (vapour explosion in the reactor vessel, hydrogen explosion, and so on). It describes the management of a core fusion accident for pressurized water reactors, for which a guide has been designed, the GIAG (intervention guide for a severe accident situation). The principles of such an intervention are described, and then the approach for an EPR reactor

  18. Nuclear Reactors

    Energy Technology Data Exchange (ETDEWEB)

    Hogerton, John

    1964-01-01

    This pamphlet describes how reactors work; discusses reactor design; describes research, teaching, and materials testing reactors; production reactors; reactors for electric power generation; reactors for supply heat; reactors for propulsion; reactors for space; reactor safety; and reactors of tomorrow. The appendix discusses characteristics of U.S. civilian power reactor concepts and lists some of the U.S. reactor power projects, with location, type, capacity, owner, and startup date.

  19. Beaulieu-sur-Loire

    OpenAIRE

    2014-01-01

    http://atlas.patrimoines.culture.fr/atlas/trunk/index.php?ap_theme=DOM_2.01.02&ap_bbox=2.732;47.494;2.875;47.581 Situé dans les basses terrasses de la rive gauche de la Loire, à 300 m du fleuve, sur une ancienne montille arasée par l'érosion et l'agriculture, ce site se caractérise par deux occupations, néolithique et gallo-romaine, sur une superficie approximative de 1,5 hectare. Il fait partie d'une vaste zone d'occupation gallo-romaine avec la villa de Gannes à 800 m au sud-ouest, sur la r...

  20. The EPR in a few words: all you need to know about the EPR nuclear reactor; L'EPR en bref: ce qu'il faut savoir sur le reacteur nucleaire EPR

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2009-07-01

    After a brief presentation of the EPR (European - or Evolutionary - Pressurized Reactor) type nuclear reactor, this paper, proposed by the collective group 'Stop EPR', develops the following points: EPR is as dangerous as other reactors; EPR flouts democracy; France's energy demand do not need the construction of EPRs; the construction of EPRs is not a factor of economical and social development; EPR should not be constructed neither in France nor elsewhere and the present building sites should be cancelled; the EPR will not help France to increase its energy independence and protect itself from oil price increases; choosing the EPR is incompatible with the large investments to be made in energy conservation and renewable energies; the EPR is not a solution to climate change; the VHV line corridor that will starts at Flamanville is not justified and poses risks to the environment and public health

  1. High energy resolution and high count rate gamma spectrometry measurement of primary coolant of generation 4 sodium-cooled fast reactor; Spectrometrie gamma haute resolution et hauts taux de comptage sur primaire de reacteur de type generation 4 au sodium liquide

    Energy Technology Data Exchange (ETDEWEB)

    Coulon, R.

    2010-11-10

    Sodium-cooled Fast Reactors are under development for the fourth generation of nuclear reactor. Breeders reactors could gives solutions for the need of energy and the preservation of uranium resources. An other purpose is the radioactive wastes production reduction by transmutation and the control of non-proliferation using a closed-cycle. These thesis shows safety and profit advantages that could be obtained by a new generation of gamma spectrometry system for SFR. Now, the high count rate abilities, allow us to study new methods of accurate power measurement and fast clad failure detection. Simulations have been done and an experimental test has been performed at the French Phenix SFR of the CEA Marcoule showing promising results for these new measurements. (author) [French] Les reacteurs a neutrons rapides refroidis au sodium sont en developpement en vue d'assurer une quatrieme generation de reacteurs repondant a la demande energetique, tout en assurant la preservation des ressources d'uranium par un fonctionnement en surgenerateur. L'objectif de la filiere est egalement d'ameliorer la gestion de la radiotoxicite des dechets produits par transmutation des actinides mineurs et de controler la non-proliferation par un fonctionnement en cycle ferme. Une instrumentation de surveillance et de controle de ce type de reacteur a ete etudiee dans cette these. La spectrometrie gamma de nouvelle generation permet, par les hauts taux de traitement aujourd'hui accessibles, d'envisager de nouvelles approches pour suivre avec une precision accrue la puissance neutronique et de detecter plus precocement des ruptures de gaine combustible. Des simulations numeriques ont ete realisees et une campagne d'essai a ete menee a bien sur le reacteur Phenix de Marcoule. Des perspectives prometteuses ont ete mises en exergue pour ces deux problematiques

  2. Synthesis of the IRSN report on the second safety re-inspection of the Orphee research reactor; Synthese du rapport de l'IRSN sur le deuxieme reexamen de surete du reacteur de recherche ORPHEE

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2010-09-09

    The second safety inspection of the Orphee base nuclear installation notably relies on international and French return on experience. This inspection addressed the robustness of the installation against extreme aggressions, organisational processes, radiation protection, waste and effluent management, the security of the reactor operation, handling operation security, nuclear waste warehousing safety, internal aggressions, the third confinement barrier, and the radiological consequences of incidental and accidental situations

  3. 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

    Energy Technology Data Exchange (ETDEWEB)

    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.

  4. The OPECST proposes to replace one out of 2 reactors at the end of their life by EPR; L'OPECST propose de remplacer un reacteur sur deux en fin de vie par des EPR

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    2011-11-15

    The OPECST, a commission composed of parliamentarians, has studied the consequences of various energy policies concerning nuclear power. The first scenario is the continuation of the today's energy policy: a production rate of nuclear electricity around 75% that gives a contribution of 1.5% to the country's growth rate through the keeping of low electricity prices. The second scenario is a brutal nuclear energy phaseout that will lead to a sharp increase of electricity costs, a degradation of the energy independence rate of the country and the loss of 400.000 direct and indirect jobs. The third scenario follows a reasoned policy that allows the maturing of renewable energies by replacing only one out of 2 reactors coming at the end of their service life by an EPR. This scenario will lead to a production rate of nuclear electricity of about 55% by 2050. (A.C.)

  5. Contribution of prototypic material tests on the Plinius platform to the study of nuclear reactor severe accident; Contribution des essais en materiaux prototypiques sur la plate-forme Plinius a l'etude des accidents graves de reacteurs nucleaires

    Energy Technology Data Exchange (ETDEWEB)

    Journeau, Ch

    2008-01-15

    The PLINIUS experimental platform at CEA Cadarache is dedicated to the experimental study of nuclear reactor severe accidents thanks to experiments between 2000 and 3500 K with prototypic corium. Corium is the mixture that would be formed by an hypothetical core melting and its mixing with structural materials. Prototypical corium has the same chemical composition as the corium corresponding to a given accident scenario but has a different isotopic composition (use of depleted uranium,...). Research programs and test series have been performed to study corium thermophysical properties, fission product behaviour, corium spreading, solidification and interaction with concrete as well as its coolability. It was the frame of research training of many students and was realized within national, European and international collaborations. (author)

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2002-07-01

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

  7. First remarks on the initiative of conception and evaluation of the safety of the reactors of the fourth generation; Premieres reflexions sur la demarche de conception et d'evaluation de la surete des reacteurs de quatrieme generation

    Energy Technology Data Exchange (ETDEWEB)

    Clement, Ch.; Maliverney, B.; Mulet-Marquis, D.; Sauvage, J.F. [Electricite de France (EDF), 75 - Paris (France); Guesdon, B. [Technical Secretary (France); Carluec, B.; Ehster, S. [AREVA NP, 92 - Paris la Defense (France); Greneche, D. [AREVA NC, 78 - Velizy Villacoublay (France); Anzieu, P. [CEA Saclay, 91 - Gif sur Yvette (France); Fiorini, G.L. [CEA Cadarache, 13 - Saint Paul lez Durance (France); Rozenholc, M.; Vitton, F.; Rouyer, J.L

    2007-09-15

    The objectives of the nuclear systems of the fourth generation impose ambitious requirements which concern the sustainable development, the competitiveness, the safety, the reliability, the resistance to proliferation and the physical protection. The examination of the policies of safety applicable to these systems is led at the same moment to the national and international levels. In France, thoughts on the safety is organized within the French consultative group of safety (G.C.F.S.) which collects the industrial actors and of research and development involved in the development of the new systems. Within the framework of the initiatives of international harmonization, the G.C.F.S. suggests defining recommendations common to all the concepts of the fourth generation reactors then on the basis of this neutral frame towards the technologies, establishing specific recommendations for each of the systems. (N.C.)

  8. H Reactor

    Data.gov (United States)

    Federal Laboratory Consortium — The H Reactor was the first reactor to be built at Hanford after World War II.It became operational in October of 1949, and represented the fourth nuclear reactor on...

  9. Modelling of the hydrogen effects on the morphogenesis of hydrogenated silicon nano-structures in a plasma reactor; Modelisation des effets de l'hydrogene sur la morphogenese des nanostructures de silicium hydrogene dans un reacteur plasma

    Energy Technology Data Exchange (ETDEWEB)

    Brulin, Q

    2006-01-15

    This work pursues the goal of understanding mechanisms related to the morphogenesis of hydrogenated silicon nano-structures in a plasma reactor through modeling techniques. Current technologies are first reviewed with an aim to understand the purpose behind their development. Then follows a summary of the possible studies which are useful in this particular context. The various techniques which make it possible to simulate the trajectories of atoms by molecular dynamics are discussed. The quantum methods of calculation of the interaction potential between chemical species are then developed, reaching the conclusion that only semi-empirical quantum methods are sufficiently fast to be able to implement an algorithm of quantum molecular dynamics on a reasonable timescale. From the tools introduced, a reflection on the nature of molecular metastable energetic states is presented for the theoretical case of the self-organized growth of a linear chain of atoms. This model - which consists of propagating the growth of a chain by the successive addition of the atom which least increases the electronic energy of the chain - shows that the Fermi level is a parameter essential to self organization during growth. This model also shows that the structure formed is not necessarily a total minimum energy structure. From all these numerical tools, the molecular growth of clusters can be simulated by using parameters from magnetohydrodynamic calculation results of plasma reactor modeling (concentrations of the species, interval between chemical reactions, energy of impact of the reagents...). The formation of silicon-hydrogen clusters is thus simulated by the successive capture of silane molecules. The structures formed in simulation at the operating temperatures of the plasma reactor predict the formation of spherical clusters constituting an amorphous silicon core covered by hydrogen. These structures are thus not in a state of minimum energy, contrary to certain experimental

  10. Le réseau d'échanges des savoirs de belleville e ménilmontant: uma discussão sobre associativismo e reciprocidade no mundo contemporâneo

    Directory of Open Access Journals (Sweden)

    Laura Graziela Gomes

    2001-12-01

    Full Text Available O presente artigo tem como objetivo tecer algumas reflexões sobre os modos de apropriação locais de uma forma associativa francesa específica - le réseau d' échanges des savoirs - de Belleville e Ménilmontant, dois quartiers populares, sediados no leste parisiense. A partir de minha experiência como participante do reseau, observações e conversas com os demais participantes, conclui que, basicamente, tratam-se de dois modos: o primeiro, relativo à produção de localidade, da condição de pertença dos moradores do quartier; o segundo, relativo à produção de capital social, traduzido em confiança e, por sua vez, formas de cooperação. O importante a ser ressaltado é que esses dois modos de apropriação não são exclusivos, ambos convivem, fundem- se e se interpenetram.

  11. Innovative Approach to Validation of Ultraviolet (UV) Reactors for Disinfection in Drinking Water Systems

    Science.gov (United States)

    Slide presentation at Conference: ASCE 7th Civil Engineering Conference in the Asian Region. USEPA in partnership with the Cadmus Group, Carollo Engineers, and other State & Industry collaborators, are evaluating new approaches for validating UV reactors to meet groundwater & sur...

  12. Comentarios desde el Sur

    Directory of Open Access Journals (Sweden)

    Tatiana Cordero Velásquez

    2011-05-01

    Full Text Available Este texto ahonda en las preguntas que plantea el Dossier: ¿Cómo se piensa lo queer en AméricaLatina? La autora analiza los contenidos de lo político en lo queer, sus aportes y limites, y la pertinenciadel concepto. Subraya la ausencia de una perspectiva de género en los estudios gay yqueer anteriores, y la relación entre sujetos LGBTI y la academia en la trayectoria de lo queer ennuestro contexto. Analiza el lugar de lo femenino en tres de los cinco artículos que abordan lasidentidades gay y trans y la ausencia de análisis sobre lo masculino en lo lésbico, bisexual o transmasculino como reflejo de la estratificación en la producción de conocimiento en torno al ‘cuerpopolítico queer’. A la vez, destaca la contribución de este dossier a la producción de conocimientoen el Sur así como a la complejización de este debate.

  13. Reactor Physics

    Energy Technology Data Exchange (ETDEWEB)

    Ait Abderrahim, A

    2001-04-01

    The Reactor Physics and MYRRHA Department of SCK-CEN offers expertise in various areas of reactor physics, in particular in neutronics calculations, reactor dosimetry, reactor operation, reactor safety and control and non-destructive analysis of reactor fuel. This expertise is applied in the Department's own research projects in the VENUS critical facility, in the BR1 reactor and in the MYRRHA project (this project aims at designing a prototype Accelerator Driven System). Available expertise is also used in programmes external to the Department such as the reactor pressure steel vessel programme, the BR2 reactor dosimetry, and the preparation and interpretation of irradiation experiments by means of neutron and gamma calculations. The activities of the Fuzzy Logic and Intelligent Technologies in Nuclear Science programme cover several domains outside the department. Progress and achievements in these topical areas in 2000 are summarised.

  14. Reactor safeguards

    CERN Document Server

    Russell, Charles R

    1962-01-01

    Reactor Safeguards provides information for all who are interested in the subject of reactor safeguards. Much of the material is descriptive although some sections are written for the engineer or physicist directly concerned with hazards analysis or site selection problems. The book opens with an introductory chapter on radiation hazards, the construction of nuclear reactors, safety issues, and the operation of nuclear reactors. This is followed by separate chapters that discuss radioactive materials, reactor kinetics, control and safety systems, containment, safety features for water reactor

  15. Reactor operation

    CERN Document Server

    Shaw, J

    2013-01-01

    Reactor Operation covers the theoretical aspects and design information of nuclear reactors. This book is composed of nine chapters that also consider their control, calibration, and experimentation.The opening chapters present the general problems of reactor operation and the principles of reactor control and operation. The succeeding chapters deal with the instrumentation, start-up, pre-commissioning, and physical experiments of nuclear reactors. The remaining chapters are devoted to the control rod calibrations and temperature coefficient measurements in the reactor. These chapters also exp

  16. Reactor Neutrinos

    OpenAIRE

    Soo-Bong Kim; Thierry Lasserre; Yifang Wang

    2013-01-01

    We review the status and the results of reactor neutrino experiments. Short-baseline experiments have provided the measurement of the reactor neutrino spectrum, and their interest has been recently revived by the discovery of the reactor antineutrino anomaly, a discrepancy between the reactor neutrino flux state of the art prediction and the measurements at baselines shorter than one kilometer. Middle and long-baseline oscillation experiments at Daya Bay, Double Chooz, and RENO provided very ...

  17. Retour sur les images d’organisations

    OpenAIRE

    Audigier, Nathalie; Boutin, Éric; Bryon-Portet, Céline; Buisson, Lysiane; Cousineau, Marie-Marthe; Cousserand, Isabelle; Dilliere-Brooks, Stéphanie; Hamel, Sylvie; Hardy, Mylène; Heller, Thomas; Laborde, Aurélie; Lagacé, Martine; Lenay Blason, Alexandra; Le Moënne, Christian; Liu, Pei

    2011-01-01

    Ce numéro 34 de Communication & Organisation est consacré aux approches communicationnelles de l’image des organisations. Les contributions portent sur des aspects théoriques de définition de l’image, sur son application aux organisations, sur des aspects plus méthodologiques, et enfin sur les enjeux critiques qui entourent les pratiques organisationnelles centrées sur l’image. Depuis les années 1970, ce sont surtout les sciences de gestion et la littérature managériale qui ont produit plusie...

  18. Multifunctional reactors

    NARCIS (Netherlands)

    Westerterp, K.R.

    1992-01-01

    Multifunctional reactors are single pieces of equipment in which, besides the reaction, other functions are carried out simultaneously. The other functions can be a heat, mass or momentum transfer operation and even another reaction. Multifunctional reactors are not new, but they have received much

  19. California Sur, México

    Directory of Open Access Journals (Sweden)

    Francisco Higinio Ruiz Espinoza

    2008-01-01

    Full Text Available En la Universidad Autónoma de Baja California Sur situada al sur del Estado de Baja California Sur, México, se desarrolló un experimento durante 3 años (2002 – 2004. Evaluándose los datos climáticos en la zona, a partir de la información proporcionada por la Comisión Nacional del Agua. Las variables climáticas evaluadas fueron temperatura (T, humedad relativa (HR, evaporación (E, promediados por décadas para el período correspondiente al desarrollo de la investigación, mientras que las variables biológicas fueron rendimiento, área foliar (AF e índice de área foliar (IAF, tasa relativa de crecimiento (TRC, tasa de asimilación neta (TAN y masa seca. Se aplicó un análisis estadístico descriptivo y multivariado, las medias se compararon por Tukey al 5 % de probabilidad, con análisis factorial, empleando el programa STATISTICA 6.0. Los resultados mostraron la relación de la temperatura y la humedad relativa con el rendimiento, lo que establece que para el máximo rendimiento de albahaca en las condiciones en que se condujo el experimento la temperatura de 32 oC y la humedad relativa de 58 % fueron las mejores

  20. Analysis on Belleville Spring Fracture of Controlling Gear of Gas Insulated Switchgear in 220 kV Substation%220 kV 变电站气体绝缘金属封闭开关设备操作机构碟形弹簧断裂分析

    Institute of Scientific and Technical Information of China (English)

    李文胜; 董重里; 胡平; 王伟; 林介东

    2016-01-01

    通过宏观检查、金相试验、光谱分析、洛氏硬度试验、扫描电镜观察和能谱分析等试验,对一起220 kV变电站气体绝缘金属封闭开关设备(gas insulated switchgear,GIS)操作机构碟形弹簧断裂的原因进行分析。结果表明,碟形弹簧断裂的原因可以推断是弹簧下表面外径边缘至 U 形凹槽的区域在制造过程中形成原始缺陷,此处存在应力集中现象,在使用过程中,裂纹扩展并最终导致弹簧断裂。此外,碟形弹簧的显微组织保留了明显的马氏体针状形态,还出现了少量的羽毛状回火贝氏体,这些特征表明弹簧在使用过程中较易发生脆性断裂。%This paper analyzes reasons for Belleville spring fracture of controlling gear of gas insulated switchgear in 220 kV substation by experiments of microscopic test,metallographic test,spectral analysis,Rockwell hardness test,scanning elec-tron microscope observation,energy spectrum analysis,and so on. Results indicate that reasons for Belleville spring fracture may be deduced for original defect of the area along the edge of external diameter of the lower surface of the spring to the U-shaped groove in manufacturing process where exists stress concentration,and in use procedure,cracks extend and finally cause spring fracture. In addition,microscopic structure of the Belleville spring keeps obvious martensitic acicular form and there is a little featheriness tempered bainite,which indicates that brittle fracture is easy to occur on the spring in use procedure.

  1. Reactor vessel

    OpenAIRE

    Makkee, M.; Kapteijn, F.; Moulijn, J.A

    1999-01-01

    A reactor vessel (1) comprises a reactor body (2) through which channels (3) are provided whose surface comprises longitudinal inwardly directed parts (4) and is provided with a catalyst (6), as well as buffer bodies (8, 12) connected to the channels (3) on both sides of the reactor body (2) and comprising connections for supplying (9, 10, 11) and discharging (13, 14, 15) via the channels (3) gases and/or liquids entering into a reaction with each other and substances formed upon this reactio...

  2. NUCLEAR REACTOR

    Science.gov (United States)

    Miller, H.I.; Smith, R.C.

    1958-01-21

    This patent relates to nuclear reactors of the type which use a liquid fuel, such as a solution of uranyl sulfate in ordinary water which acts as the moderator. The reactor is comprised of a spherical vessel having a diameter of about 12 inches substantially surrounded by a reflector of beryllium oxide. Conventionnl control rods and safety rods are operated in slots in the reflector outside the vessel to control the operation of the reactor. An additional means for increasing the safety factor of the reactor by raising the ratio of delayed neutrons to prompt neutrons, is provided and consists of a soluble sulfate salt of beryllium dissolved in the liquid fuel in the proper proportion to obtain the result desired.

  3. Reactor Neutrinos

    Directory of Open Access Journals (Sweden)

    Soo-Bong Kim

    2013-01-01

    Full Text Available We review the status and the results of reactor neutrino experiments. Short-baseline experiments have provided the measurement of the reactor neutrino spectrum, and their interest has been recently revived by the discovery of the reactor antineutrino anomaly, a discrepancy between the reactor neutrino flux state of the art prediction and the measurements at baselines shorter than one kilometer. Middle and long-baseline oscillation experiments at Daya Bay, Double Chooz, and RENO provided very recently the most precise determination of the neutrino mixing angle θ13. This paper provides an overview of the upcoming experiments and of the projects under development, including the determination of the neutrino mass hierarchy and the possible use of neutrinos for society, for nonproliferation of nuclear materials, and geophysics.

  4. Chemical Reactors.

    Science.gov (United States)

    Kenney, C. N.

    1980-01-01

    Describes a course, including content, reading list, and presentation on chemical reactors at Cambridge University, England. A brief comparison of chemical engineering education between the United States and England is also given. (JN)

  5. Reactor Neutrinos

    OpenAIRE

    Lasserre, T.; Sobel, H.W.

    2005-01-01

    We review the status and the results of reactor neutrino experiments, that toe the cutting edge of neutrino research. Short baseline experiments have provided the measurement of the reactor neutrino spectrum, and are still searching for important phenomena such as the neutrino magnetic moment. They could open the door to the measurement of coherent neutrino scattering in a near future. Middle and long baseline oscillation experiments at Chooz and KamLAND have played a relevant role in neutrin...

  6. Report by the AERES on the unit: Reactor Study Department (DER) under the supervision of the establishments and bodies: Atomic Energy and Alternative Energies Commission (CEA); Rapport de l'AERES sur l'unite: Departement d'Etudes des Reacteurs (DER) sous tutelle des etablissements et organismes: CEA

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2011-02-15

    This report is a kind of audit report on a research laboratory, the DER (Departement d'Etudes des Reacteurs, Reactor Study Department) whose activity if focused on four main themes: neutron transport simulation in reactor cores, thermal-hydraulic simulation of reactors, design and safety of innovative reactors, nuclear instrumentation for reactors. The authors discuss an assessment of the whole unit activities in terms of strengths and opportunities, aspects to be improved, risks and recommendations, productions and publications, scientific quality, influence and attractiveness (awards, recruitment capacity, capacity to obtain financing and to tender, participation to international programs), strategy and governance, and project. These same aspects are then discussed and commented for each theme

  7. Synthesis of the IRSN report of general directions to be retained for an evolution of the referential of investigation of core cooling after leakage on the primary circuit of a pressurized water reactor; Synthese du rapport de l'IRSN sur les orientations a retenir en vue d'une evolution du referentiel d'etude du refroidissement du coeur suite a une fuite sur le circuit primaire d'un reacteur a eau sous pression

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2010-05-15

    This document from the French Nuclear Safety and Radioprotection Institute (IRSN) describes the accident of loss of primary coolant in a pressurized water reactor, and its consequences with two possible damage modes (ductile and brittle). It describes the present requirement referential associated to this accident, and justifies the need to make this referential evolve. It discusses the main directions and topics to be examined again: scenarios, requirements and criteria, physical phenomena to be taken into account. For each of them, it comments the options proposed by EDF and gives the IRSN opinion on these options

  8. La piraterie sur le web

    CERN Document Server

    2002-01-01

    Les échanges de toutes sortes sont facilités à l'extrême par le web: des forums, des vidéoconférences, le commerce à distance, ou tout simplement la célérité des courriers électroniques ou la convivialité des chats, tout cela participe de la société de communication. Une certaine partie du monde découvre le nouvel horizon des échanges quasi instantanés, mais... les transactions sur le web sont-elles vraiment s res?

  9. Reports by the Parliamentary Office for scientific and technological assessments. Tuesday, May 24, 2011. Hearing on the protection of a reactor core and critical circuit; Comptes rendus de l' Office Parlementaire d'Evaluation des Choix Scientifiques et Technologiques. Mardi 24 mai 2011. Audition sur la protection du coeur et des circuits critiques d'un reacteur

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2011-05-15

    In the context created by the Fukushima accident, members of the French Parliament, representatives of the French nuclear safety authority (ASN), of the French Institute for radiation protection and nuclear safety (IRSN), and of the CEA describe and discuss the technical aspects and mechanism of defence-in-depth of nuclear reactors (i.e. the different and successive levels of protection aimed at ensuring the reactor integrity to be maintained, even in case of failure of a critical circuit). Then, they discuss advances and researches in the field of protection of reactors. Several research programs are evoked which concern different elements of a nuclear plants such as the fuel, the reactor, loss of cooling system, and so on; these programs are based either on experiments or on simulations

  10. Sonochemical Reactors.

    Science.gov (United States)

    Gogate, Parag R; Patil, Pankaj N

    2016-10-01

    Sonochemical reactors are based on the generation of cavitational events using ultrasound and offer immense potential for the intensification of physical and chemical processing applications. The present work presents a critical analysis of the underlying mechanisms for intensification, available reactor configurations and overview of the different applications exploited successfully, though mostly at laboratory scales. Guidelines have also been presented for optimum selection of the important operating parameters (frequency and intensity of irradiation, temperature and liquid physicochemical properties) as well as the geometric parameters (type of reactor configuration and the number/position of the transducers) so as to maximize the process intensification benefits. The key areas for future work so as to transform the successful technique at laboratory/pilot scale into commercial technology have also been discussed. Overall, it has been established that there is immense potential for sonochemical reactors for process intensification leading to greener processing and economic benefits. Combined efforts from a wide range of disciplines such as material science, physics, chemistry and chemical engineers are required to harness the benefits at commercial scale operation.

  11. The risk of shortage of radioelements at medical use must not lead to overlook the reactors safety that produce them; Le risque de penurie de radioelements a usage medical ne doit pas conduire a faire l'impasse sur la surete des reacteurs qui les produisent

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2009-07-01

    As the reactors supplying the world production of radioelements for medical use have over 40 years of operation, the nuclear safety authority alerts the stake holders on the necessity to prevent the conflicts between public health and nuclear safety in the production of these elements; Asn estimates that the solution is not to extend the lifetime of the reactors but goes for a new international concerted approach. The most of the present production comes from five old reactors: N.R.U. at Chalk river (Canada, 40%), H.F.R. at Petten (Netherlands, 30%), Safari at Pelindaba (South Africa, 10%) B.R.2 at Mol (Belgium, 9%) and Osiris at Saclay (France, 5%). In this context, Asn organised in january 2009 a seminar on the safety-availability of facilities of radio-isotopes production with safety authorities of the concerned countries. Nea organised a seminar on the radiopharmaceuticals supply at the end of january 2009. (N.C.)

  12. SARNET european excellence network on nuclear reactor major accidents. Display and realizations after a year of operating; Sarnet reseau d'excellence europeen sur les accidents graves de reacteur nucleaire. Son deploiement et ses realisations apres une annee de fonctionnement

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2005-03-15

    The Sarnet (Severe Accident Research NETwork of excellence) is devoted to the research on major accidents of water cooled reactors. The developed knowledge will be integrated in a simulation tool ASTEC co-developed with the IRSN and the GRS. This evaluation report presents the context, the objectives and the program of the Sarnet network. It discusses the network operating and the ASTEC simulation code. Some examples of experimental programs are provided. (A.L.B.)

  13. Hybrid adsorptive membrane reactor

    Science.gov (United States)

    Tsotsis, Theodore T. (Inventor); Sahimi, Muhammad (Inventor); Fayyaz-Najafi, Babak (Inventor); Harale, Aadesh (Inventor); Park, Byoung-Gi (Inventor); Liu, Paul K. T. (Inventor)

    2011-01-01

    A hybrid adsorbent-membrane reactor in which the chemical reaction, membrane separation, and product adsorption are coupled. Also disclosed are a dual-reactor apparatus and a process using the reactor or the apparatus.

  14. D and DR Reactors

    Data.gov (United States)

    Federal Laboratory Consortium — The world's second full-scale nuclear reactor was the D Reactor at Hanford which was built in the early 1940's and went operational in December of 1944.D Reactor ran...

  15. Hybrid adsorptive membrane reactor

    Science.gov (United States)

    Tsotsis, Theodore T.; Sahimi, Muhammad; Fayyaz-Najafi, Babak; Harale, Aadesh; Park, Byoung-Gi; Liu, Paul K. T.

    2011-03-01

    A hybrid adsorbent-membrane reactor in which the chemical reaction, membrane separation, and product adsorption are coupled. Also disclosed are a dual-reactor apparatus and a process using the reactor or the apparatus.

  16. 基于MATLAB7.0的无极绳绞车制动器碟形弹簧优化设计%Optimum Design of Belleville Springs of Brake on the Endless Rope Winch with MATLAB7.0

    Institute of Scientific and Technical Information of China (English)

    王成锋; 侯友夫; 胡志鹏

    2012-01-01

    The optimum design model of the belleville spring which is used in the hydraulic cylinder of safety brake of endless rope winch was established. To obtain the most minor volume and quality, the outside diameter, inside diameter, height, thickness, number flats as a group of design variable was taken for the process of optimized design using the function of MATLAB7. 0. The optimi-zation result shows that the method is simple and feasible.%建立了无极绳绞车安全制动器液压缸中的碟形弹簧优化设计模型.以体积、质量最小为目标,取碟簧的外径、内径、自由高度、厚度和组合片数为设计变量,运用MATLAB7.0软件中的fmincon函数对其进行了优化.优化结果表明,该方法简便可行.

  17. Cartes sur fonds d'images spatiales

    Directory of Open Access Journals (Sweden)

    Fernand VERGER

    1988-06-01

    Full Text Available La qualité géométrique, la vue synoptique sur de grandes étendues, le caractère souvent expressif des images obtenues à partir de l'espace ont provoqué l'utilisation de fonds d'images spatiales avec des surcharges chorogra phiques. On peut proposer une typologie de ces documents sur fonds d'images satellitaires dont un spécimen au 1/25 000 est présenté à partir des données SPOT.

  18. Reactor and method of operation

    Science.gov (United States)

    Wheeler, John A.

    1976-08-10

    A nuclear reactor having a flattened reactor activity curve across the reactor includes fuel extending over a lesser portion of the fuel channels in the central portion of the reactor than in the remainder of the reactor.

  19. Synthesis of the IRSN report on the control-command architecture of the Flamanville 3 EPR reactor and the associated platforms; Synthese du rapport de l'IRSN portant sur l'architecture du controle commande du reacteur EPR de Flamanville 3 et les plateformes associees

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2009-06-15

    This document briefly reports the IRSN's comments on the robustness of the control-command architecture of the Flamanville 3 EPR (European pressurized reactor), that is of the equipment which, to various extent, contribute to the installation safety. This report identifies the equipment the robustness of which should be improved, outlines the problems created by the complexity of computerized systems. Notably, the authors comment the ability of the off-the-shelf computer platforms acquired by EDF to deal with the nuclear context.

  20. Inquiry in the public interest, held at Cadarache into the construction of the reactor 'Jules Horowitz' and the problems related to the public dialogue; L'enquete d'utilite publique sur la creation du 'reacteur Jules Horowitz' a Cadarache et la participation locale

    Energy Technology Data Exchange (ETDEWEB)

    Bottiglioni, F

    2007-07-15

    In this paper are presented the main points of the inquiry taken by an official board into the demand of the Cea to create a new research tool, the 'Jules Horowitz Reactor', in its research center of Cadarache. The increasing involvement of the people in the decision-making procedures dealing with important projects is summed up, so as the distinctive features of the different regulations that frame the public participation are stressed. Some improvements are suggested to carry through next inquiries faster and more easily. The participation of the public has been low: only 11 people or associations have left their remarks to the inquiry members despite the large audience that attended the different meetings and debates organized on the issue by the CNDP (national board for public debate)

  1. Nitrogen treatment from digestat of biogas plants in a moving bed biofilm reactor; Projet de recherche pilote. Traitement de l'azote des digestats issus d'installations de biogaz au moyen d'un reacteur a biofilm sur support mobile - Rapport final

    Energy Technology Data Exchange (ETDEWEB)

    Roches, S.; Bakx, T.; Membrez, Y. [EREP SA, Aclens (Switzerland); Baggenstos, M.; Chappaz, A. [Wabag Water Technology Ltd, Winterthur (Switzerland); Holliger, Ch. [Swiss Federal Institute of Technology, EPFL, Laboratory for Environmental Biotechnology, Lausanne (Switzerland)

    2010-11-15

    Ammonia emissions are a source for polluting ecosystems, causing in particular acidification and eutrophication of the affected areas. In Switzerland 90% of the atmospheric ammonia emissions are due to agriculture, mostly during storage and use of animal manures and slurries. Anaerobic digestion of these manures and slurries produces renewable energy and stabilises the agricultural effluents. However, it does not solve the ammonia problem; on the contrary, it releases an additional amount of ammonium while mineralizing a large part of the organic nitrogen. A previous study dealing with the biological removal of ammonia from digested manures was conducted at the Laboratory of Environmental Biotechnology, EPFL. It has shown that it is possible to obtain simultaneously a conversion of ammonium and nitrogen removal in a same continuously aerated aerobic reactor, using a mobile support for fixing the biomass. The obtained efficiencies were high, with 90% of the ammonium being converted of which 80% as N{sub 2}-gas. This current study proposed to test the process at pilot scale, to evaluate the transferability of the technique to a full-scale application and to determine the operating parameter. The results are as follows: (i) It is possible to obtain high nitrification and denitrification rates without pre-treating the digestat or adding a carbon source; (ii) Biochemical reactions are extremely sensitive to the oxygenation rate, which in turn is very sensitive to the liquid characteristics in the reactor, such as the dry matter content. It fairly complicates maintaining simultaneous nitrification and denitrification; (iii) At a minimum hydraulic residence time of 4 days, over 90% of the ammonium is converted and 85% of it is removed. These results provide the basic design parameters for a full-scale installation. Depending on the performance desired, it would have a volume going from 30 to 60 m{sup 3} for a 400 m{sup 3} digester. The aeration rate would be between 300

  2. Reactor Physics Programme

    Energy Technology Data Exchange (ETDEWEB)

    De Raedt, C

    2000-07-01

    The Reactor Physics and Department of SCK-CEN offers expertise in various areas of reactor physics, in particular in neutronics calculations, reactor dosimetry, reactor operation, reactor safety and control and non-destructive analysis on reactor fuel. This expertise is applied within the Reactor Physics and MYRRHA Research Department's own research projects in the VENUS critical facility, in the BR1 reactor and in the MYRRHA project (this project aims at designing a prototype Accelerator Driven System). Available expertise is also used in programmes external to the Department such as the reactor pressure steel vessel programme, the BR2 reactor dosimetry, and the preparation and interpretation of irradiation experiments. Progress and achievements in 1999 in the following areas are reported on: (1) investigations on the use of military plutonium in commercial power reactors; (2) neutron and gamma calculations performed for BR-2 and for other reactors; (3) the updating of neutron and gamma cross-section libraries; (4) the implementation of reactor codes; (6) the management of the UNIX workstations; and (6) fuel cycle studies.

  3. Assessment of a dynamic model of a pant-legged circulating fluidized bed reactor on Provence 250 MWE plant; Evaluation d`une modelisation dynamique d`un foyer de LFC a deux jambes sur la centrale LFC 250 MWE de Provence

    Energy Technology Data Exchange (ETDEWEB)

    Montat, D.

    1996-12-31

    A demonstration dynamic model of the pant-legged furnace of Provence CFB power plant was programmed. It enables characterization of the dynamic behaviour of the gas-particle flow in the furnace: memory effect, risk to half-leg drainage, dissymmetrical air injection effect. As to quality, there is good agreement between the model and measurements performed at the Provence plant during start-up tests (operating conditions differing from the initial conditions). From the quantity standpoint, after adaptation of a single adjustment parameter, the results are conclusive, but not totally adequate: after 1 hour, the model deviates from the measured values by more than 10 %. In its present state, the model provides, at the least, valuable assistance for interpretation of the dynamic behaviour of the Provence-reactor. Improving the model performances would entail adapting the flow laws to the Provence plant. This would require a systematic study of several operation points. Upgrading of the model could be obtained by its integration in the dynamic model of the Provence plant using the SICLE solver, or its programming using LEGO solver, or its integration in the plant control system. (author) 7 refs.

  4. Maintenance sur les infrastructures de surface

    CERN Document Server

    Chevret, P

    2000-01-01

    L'objet de ce document est de dresser le bilan de l'activité du Groupe Technical Facilities Management dans le domaine de la maintenance. Ce bilan couvre les activités techniques du génie civil, du chauffage-climatisation et de l'électricité, s'appliquant dans une large majorité au seul secteur tertiaire, tant sur le plan préventif que correctif. Les principaux paramètres indicateurs de l'activité sont situés dans leur évolution au cours des dernières années. Les auteurs abordent également les principaux projets complémentaires de maintenance, qui sont conduits pour maintenir l'état du patrimoine en dépit des restrictions budgétaires, faire face aux problèmes d'obsolescence, de défaillances récurrentes sur certains matériels, et satisfaire aux normes de sécurité. L'incidence positive de ces actions sur le nombre d'interventions de maintenance corrective est également montrée. Enfin, des perspectives de progrès sont dégagées, visant à une gestion davantage prévisionnelle de la ma...

  5. Remesas y participación laboral en Paraguay: Efectos de los desplazamientos sur-sur

    Directory of Open Access Journals (Sweden)

    Pablo Sebastián GÓMEZ

    2013-01-01

    Full Text Available Se analiza la participación laboral de los miembros de hogares receptores de remesas en Paraguay. Se aporta el estudio específico de los efectos de las remesas provenien­ tes del sur en un país del sur utilizando el enfoque de la puntuación de la propensión para enfrentar el problema de sesgo de selección. Los resultados acusan diferencias estructurales entre los hogares receptores de remesas del sur y aquellos que no lo son. Se sugiere que en un mercado laboral de alta informalidad y precariedad las remesas provenientes principalmente de Argentina se dirigen hacia los hogares en los estratos socioeconómicos más bajos y tienden a reducir la participación laboral.

  6. Modelling the cracking of pressurised water reactor fuel pellets and its consequences on the mechanical behaviour of the fuel rod; Etude de l'impact de la fissuration des combustibles nucleaires oxyde sur le comportement normal et incidentel des crayons combustible

    Energy Technology Data Exchange (ETDEWEB)

    Helfer, Th

    2006-03-15

    This thesis aims to model the cracking of pressurised water reactor fuel pellets and its consequences on the mechanical behaviour of the fuel rod. Fuel cracking has two main consequences. It relieves the stress in the pellet, upon which the majority of the mechanical and physico-chemical phenomena are dependent. It also leads to pellet fragmentation. Taking fuel cracking into account is therefore necessary to adequately predict the mechanical loading of the cladding during the course of an irradiation. The local approach to fracture was chosen to describe fuel pellet cracking. Practical considerations brought us to favour a quasi-static description of fuel cracking by means of a local damage models. These models describe the appearance of cracks by a local loss of rigidity of the material. Such a description leads to numerical difficulties, such as mesh dependency of the results and abrupt changes in the equilibrium state of the mechanical structure during unstable crack propagations. A particular attention was paid to these difficulties because they condition the use of such models in engineering studies. This work was performed within the framework of the ALCYONE fuel performance package developed at CEA/DEC/SESC which relies on the PLEIADES software platform. ALCYONE provides users with various approaches for modelling nuclear fuel behaviour, which differ in terms of the type geometry considered for the fuel rod. A specific model was developed and implemented to describe fuel cracking for each of these approaches. The 2D axisymmetric fuel rod model is the most innovative and was particularly studied. We show that it is able to assess, thanks to an appropriate description of fuel cracking, the main geometrical changes of the fuel rod occurring under normal and off-normal operating conditions. (author)

  7. LMFBR type reactor

    Energy Technology Data Exchange (ETDEWEB)

    Kawakami, Hiroto

    1995-02-07

    A reactor container of the present invention has a structure that the reactor container is entirely at the same temperature as that at the inlet of the reactor and, a hot pool is incorporated therein, and the reactor container has is entirely at the same temperature and has substantially uniform temperature follow-up property transiently. Namely, if the temperature at the inlet of the reactor core changes, the temperature of the entire reactor container changes following this change, but no great temperature gradient is caused in the axial direction and no great heat stresses due to axial temperature distribution is caused. Occurrence of thermal stresses caused by the axial temperature distribution can be suppressed to improve the reliability of the reactor container. In addition, since the laying of the reactor inlet pipelines over the inside of the reactor is eliminated, the reactor container is made compact and the heat shielding structures above the reactor and a protection structure of container walls are simplified. Further, secondary coolants are filled to the outside of the reactor container to simplify the shieldings. The combined effects described above can improve economical property and reliability. (N.H.).

  8. La cooperación sur-sur como herramienta del postdesarrollo en Colombia

    OpenAIRE

    2014-01-01

    Los nuevos escenarios internacionales enmarcados por la crisis financiera y económica, el inconformismo social y la participación de economías emergentes en los espacios de diálogo internacional, entre otros factores, han influido en la necesidad de redefinir el sistema internacional, la arquitectura de la cooperación internacional y en especial, el concepto de desarrollo. El objetivo de esta ponencia es determinar sí la cooperación sur-sur promueve el postdesarrollo en el país debido a que ...

  9. El (los Sur buscando al Sur. Una construcción entre estereotipos y realidad.

    Directory of Open Access Journals (Sweden)

    Mabel Franzone

    2010-11-01

    Full Text Available Todas las lecturas que podamos hacer del Sur, de sus propias representaciones, de aquellas vehiculizadas por el Norte, de sus creaciones, de sus reacciones, de su búsqueda constante de identidad, son lecturas de múltiples situaciones, que llaman a cruces insoslayables entre pueblos, entre distintas etnias, entre disciplinas, entre sentimientos que van desde el rechazo hasta la atracción casi magnética entre los dos hemisferios. Nuestra intención primera era la de reunir de manera aproximativa las problemáticas actuales de los Sur, ligadas a lo imaginario.

  10. Du discours sur l'Autre au discours sur soi : Le Voyage en Orient de Lamartine

    OpenAIRE

    magri-mourgues, Véronique,

    2001-01-01

    International audience; L'article veut montrer comment le discours sur l'Autre, l'étranger, peut se muer en discours réflexif sur soi. Un parcours est accompli depuis les discours antérieurs au voyage jusqu'au discours pour soi en passant par les stratégies du rapprochement entre l'Autre et le Même. Le décentrement salutaire opéré par l'approche de l'Autre n'est que temporaire même s'il s'avère nécessaire pour la (re)connaissance du Même.

  11. Speech by Prime Minister Francois Fillon. Visit of the Jules Horowitz experimental reactor works on the Commissariat a l'Energie et aux Energies Alternatives site. Cadarache, May 3, 2010; Discours du Premier ministre Francois FILLON Cadarache, lundi 3 mai 2010. Visite du chantier du Reacteur experimental Jules Horowitz sur le site du Commissariat a l'Energie Atomique et aux Energies Alternatives

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2010-07-01

    In this speech, the French Prime Minister evokes the present context, the importance of strategic technologies, and the challenge of investing in these technologies within a context of reduction of public expenses. He comments the decision of his government to finance research and education activities in different domains, and more specifically in the energy sector with this fourth generation Jules Horowitz experimental reactor. He recalls that the nuclear sector has always been very important to the eyes of the successive French governments, and outlines how this reactor will contribute to reactor operational optimization, lifetime extension and safety, nuclear fuel development, etc.

  12. Light water reactor safety

    CERN Document Server

    Pershagen, B

    2013-01-01

    This book describes the principles and practices of reactor safety as applied to the design, regulation and operation of light water reactors, combining a historical approach with an up-to-date account of the safety, technology and operating experience of both pressurized water reactors and boiling water reactors. The introductory chapters set out the basic facts upon which the safety of light water reactors depend. The central section is devoted to the methods and results of safety analysis. The accidents at Three Mile Island and Chernobyl are reviewed and their implications for light wate

  13. Nuclear reactor physics

    CERN Document Server

    Stacey, Weston M

    2010-01-01

    Nuclear reactor physics is the core discipline of nuclear engineering. Nuclear reactors now account for a significant portion of the electrical power generated worldwide, and new power reactors with improved fuel cycles are being developed. At the same time, the past few decades have seen an ever-increasing number of industrial, medical, military, and research applications for nuclear reactors. The second edition of this successful comprehensive textbook and reference on basic and advanced nuclear reactor physics has been completely updated, revised and enlarged to include the latest developme

  14. Spinning fluids reactor

    Science.gov (United States)

    Miller, Jan D; Hupka, Jan; Aranowski, Robert

    2012-11-20

    A spinning fluids reactor, includes a reactor body (24) having a circular cross-section and a fluid contactor screen (26) within the reactor body (24). The fluid contactor screen (26) having a plurality of apertures and a circular cross-section concentric with the reactor body (24) for a length thus forming an inner volume (28) bound by the fluid contactor screen (26) and an outer volume (30) bound by the reactor body (24) and the fluid contactor screen (26). A primary inlet (20) can be operatively connected to the reactor body (24) and can be configured to produce flow-through first spinning flow of a first fluid within the inner volume (28). A secondary inlet (22) can similarly be operatively connected to the reactor body (24) and can be configured to produce a second flow of a second fluid within the outer volume (30) which is optionally spinning.

  15. Decree n. 2007-534 of the 4. april 2007 allowing the creation of the base nuclear installation named Flamanville 3, including a EPR type reactor, on the site of Flamanville (Manche); Decret no 2007-534 du 10 avril 2007 autorisant la creation de l'installation nucleaire de base denommee Flamanville 3, comportant un reacteur nucleaire de type EPR, sur le site de Flamanville (Manche)

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2007-04-15

    This decree gives the authorization to EDF to create on the site of Flamanville a nuclear installation including a PWR type reactor for a power of 4500 MW and devoted to the electric production. This reactor will can use uranium oxide or a mixture of uranium oxide and plutonium oxide. Considerations concerning the safety are given, as well as the control of the impact of this exploitation on the populations and the environment. (N.C.)

  16. Reactor Vessel Surveillance Program for Advanced Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Jeong, Kyeong-Hoon; Kim, Tae-Wan; Lee, Gyu-Mahn; Kim, Jong-Wook; Park, Keun-Bae; Kim, Keung-Koo

    2008-10-15

    This report provides the design requirements of an integral type reactor vessel surveillance program for an integral type reactor in accordance with the requirements of Korean MEST (Ministry of Education, Science and Technology Development) Notice 2008-18. This report covers the requirements for the design of surveillance capsule assemblies including their test specimens, test block materials, handling tools, and monitors of the surveillance capsule neutron fluence and temperature. In addition, this report provides design requirements for the program for irradiation surveillance of reactor vessel materials, a layout of specimens and monitors in the surveillance capsule, procedures of installation and retrieval of the surveillance capsule assemblies, and the layout of the surveillance capsule assemblies in the reactor.

  17. SNTP program reactor design

    Science.gov (United States)

    Walton, Lewis A.; Sapyta, Joseph J.

    1993-06-01

    The Space Nuclear Thermal Propulsion (SNTP) program is evaluating the feasibility of a particle bed reactor for a high-performance nuclear thermal rocket engine. Reactors operating between 500 MW and 2,000 MW will produce engine thrusts ranging from 20,000 pounds to 80,000 pounds. The optimum reactor arrangement depends on the power level desired and the intended application. The key components of the reactor have been developed and are being tested. Flow-to-power matching considerations dominate the thermal-hydraulic design of the reactor. Optimal propellant management during decay heat cooling requires a three-pronged approach. Adequate computational methods exist to perform the neutronics analysis of the reactor core. These methods have been benchmarked to critical experiment data.

  18. Fast Spectrum Reactors

    CERN Document Server

    Todd, Donald; Tsvetkov, Pavel

    2012-01-01

    Fast Spectrum Reactors presents a detailed overview of world-wide technology contributing to the development of fast spectrum reactors. With a unique focus on the capabilities of fast spectrum reactors to address nuclear waste transmutation issues, in addition to the well-known capabilities of breeding new fuel, this volume describes how fast spectrum reactors contribute to the wide application of nuclear power systems to serve the global nuclear renaissance while minimizing nuclear proliferation concerns. Readers will find an introduction to the sustainable development of nuclear energy and the role of fast reactors, in addition to an economic analysis of nuclear reactors. A section devoted to neutronics offers the current trends in nuclear design, such as performance parameters and the optimization of advanced power systems. The latest findings on fuel management, partitioning and transmutation include the physics, efficiency and strategies of transmutation, homogeneous and heterogeneous recycling, in addit...

  19. Hybrid reactors. [Fuel cycle

    Energy Technology Data Exchange (ETDEWEB)

    Moir, R.W.

    1980-09-09

    The rationale for hybrid fusion-fission reactors is the production of fissile fuel for fission reactors. A new class of reactor, the fission-suppressed hybrid promises unusually good safety features as well as the ability to support 25 light-water reactors of the same nuclear power rating, or even more high-conversion-ratio reactors such as the heavy-water type. One 4000-MW nuclear hybrid can produce 7200 kg of /sup 233/U per year. To obtain good economics, injector efficiency times plasma gain (eta/sub i/Q) should be greater than 2, the wall load should be greater than 1 MW.m/sup -2/, and the hybrid should cost less than 6 times the cost of a light-water reactor. Introduction rates for the fission-suppressed hybrid are usually rapid.

  20. Geopolítica del Atlántico Sur : Las relaciones sur-sur y la presencia de las potencias hegemónicas

    OpenAIRE

    Dupuy, Héctor Adolfo; Morgante, Martín Adolfo; Stanganelli, Isabel Cecilia; Margueliche, Juan Cruz Ramón; Venturo, Eduardo; Dediego, Paola; Levis, Martín; Patronelli, Hilario; Costantino, Alejandro

    2013-01-01

    La presente ponencia da cuenta de la propuesta y avances iniciales del proyecto de investigación homónimo desarrollado en el marco del Centro de Investigaciones Geográficas. El proyecto intenta analizar el desarrollo de una geopolítica multilateral sur-sur en la región del océano Atlántico Sur, poniendo énfasis en el papel jugado por las economías emergentes y periféricas, así como la evaluación del mantenimiento de relaciones centro-periferia en la región del Atlántico Sur, apoyadas en la co...

  1. The reactor Cabri; La pile cabri

    Energy Technology Data Exchange (ETDEWEB)

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

    1964-07-01

    exceptional circumstances... - experimental investigations on power excursions linked with precise initial conditions: the aim of this work is to define the basis for theoretical research, and the limits beyond which the risks of explosion cease to be negligible. The research work will be done so as to enable checking with outside reactor experiments and to continue them in the explosion field. - studies of the behaviour of the reactor control-instrumentation. - experimental investigations related with transient operation with initial short life (study of boiling, temperature measurements, vacuum pressure and fraction...) with the aim of defining the hypotheses of a theory on swimming-pool reactor kinetics related to heat transfer phenomena, - investigations of the behaviour of fuels in reactors (these experiments are planned to be carried out in loops) Preliminary experimental results. CABRI went critical on the 21 December 1963. The first transient experiments are expected for March 1964. (authors) [French] II devenait necessaire de construire en France une pile qui permette d'etudier les conditions de fonctionnement des installations futures, de choisir, tester et mettre au point les dispositifs de securite a adopter. On a choisi une pile a eau, type de pile qui correspond aux constructions les plus nouvelles du CEA en matiere de piles laboratoire ou d'universite; il importe en effet de pouvoir evaluer les risques presentes et d'etudier les possibilites d'augmentation de puissance constamment demandees par les utilisateurs: il est particulierement interessant d'eclaircir les phenomenes d'oscillation de puissance et les risques de calefaction (burn out). Les programmes de travaux sur CABRI seront harmonises avec les travaux effectues sur les Spert americains de meme type; lors de sa construction des contacts fructueux ont ete etablis avec les specialistes americains qui ont defini les premiers de ces reacteurs. La communication donne une

  2. Multi purpose research reactor

    Energy Technology Data Exchange (ETDEWEB)

    Raina, V.K. [Research Reactor Design and Projects Division, Bhabha Atomic Research Centre, Mumbai 400085 (India)]. E-mail: vkrain@magnum.barc.ernet.in; Sasidharan, K. [Research Reactor Design and Projects Division, Bhabha Atomic Research Centre, Mumbai 400085 (India); Sengupta, Samiran [Research Reactor Design and Projects Division, Bhabha Atomic Research Centre, Mumbai 400085 (India); Singh, Tej [Research Reactor Services Division, Bhabha Atomic Research Centre, Mumbai 400085 (India)

    2006-04-15

    At present Dhruva and Cirus reactors provide the majority of research reactor based facilities to cater to the various needs of a vast pool of researchers in the field of material sciences, physics, chemistry, bio sciences, research and development work for nuclear power plants and production of radio isotopes. With a view to further consolidate and expand the scope of research and development in nuclear and allied sciences, a new 20 MWt multi purpose research reactor is being designed. This paper describes some of the design features and safety aspects of this reactor.

  3. INVAP's Research Reactor Designs

    Directory of Open Access Journals (Sweden)

    Eduardo Villarino

    2011-01-01

    Full Text Available INVAP, an Argentine company founded more than three decades ago, is today recognized as one of the leaders within the research reactor industry. INVAP has participated in several projects covering a wide range of facilities, designed in accordance with the requirements of our different clients. For complying with these requirements, INVAP developed special skills and capabilities to deal with different fuel assemblies, different core cooling systems, and different reactor layouts. This paper summarizes the general features and utilization of several INVAP research reactor designs, from subcritical and critical assemblies to high-power reactors.

  4. LMFBR type reactor

    Energy Technology Data Exchange (ETDEWEB)

    Kanbe, Mitsuru

    1997-04-04

    An LMFBR type reactor comprises a plurality of reactor cores in a reactor container. Namely, a plurality of pot containing vessels are disposed in the reactor vessel and a plurality of reactor cores are formed in a state where an integrated-type fuel assembly is each inserted to a pot, and a coolant pipeline is connected to each of the pot containing-vessel to cool the reactor core respectively. When fuels are exchanged, the integrated-type fuel assembly is taken out together with the pot from the reactor vessel in a state where the integrated-type fuel assembly is immersed in the coolants in the pot as it is. Accordingly, coolants are supplied to each of the pot containing-vessel connected with the coolant pipeline and circulate while cooling the integrated-type fuel assembly for every pot. Then, when the fuels are exchanged, the integrated type fuel assembly is taken out to the outside of the reactor together with the pot by taking up the pot from the pot-containing vessel. Then, neutron economy is improved to thereby improve reactor power and the breeding ratio. (N.H.)

  5. COMPTABILITÉ BASÉE SUR LA CONNAISSANCE

    OpenAIRE

    Tugui, Alexandru

    2005-01-01

    International audience; Dans la future société basée sur la connaissance, les connaissances constitueront des pièces de travails habituées qui seront manipulées très facilement. La comptabilité ne fait pas exception à cette pratique et aboutira à cet état suite à la standardisation des procédures, des pratiques et des méthodes comptables, au traitement intégré des données de l'entreprise, du niveau de plus en plus performant des technologies de communication, des réalisations du domaine de l'...

  6. Enquête LMD sur le web

    Directory of Open Access Journals (Sweden)

    Colette Cauvin

    2003-02-01

    Full Text Available En relation avec la mise en place des LMD, une enquête sur le web a été entreprise en janvier 2003 afin de connaître les orientations et les choix des diverses universités délivrant des diplômes de géographie ou d’une discipline similaire. Grâce à R. Schlumberger (laboratoire Image et Ville de nombreux sites ont été consultés et analysés. Qu’elle en soit remerciée.   Cependant, la lecture des informations a été plus malaisée que prévue en raison, en particulier, de la multiplicité des langue...

  7. Une fresque hagiographique sur Martin Luther King

    OpenAIRE

    Portes, Jacques

    2015-01-01

    Ce film est sorti en prévision du cinquantième anniversaire des grandes manifestations de Selma (Alabama) de janvier-mars 1965, qui ont débouché en juillet suivant sur le vote de la loi du droit de vote qui va assurer aux électeurs noirs l’accès au suffrage, dont ils étaient privés dans le Sud depuis la fin du XIXe siècle. « Selma » a mis en avant une fois de plus la personnalité de Martin Luther King, à la fois prudent et déterminé, dont le rôle précédent avait été largement reconnu par son ...

  8. Epistemologías del Sur

    Directory of Open Access Journals (Sweden)

    Boaventura de Sousa Santos

    2011-01-01

    Full Text Available Es un hecho irreversible que el logos eurocéntrico ha implosionado en sus propias fuentes de desarrollo político y económico. El peligro de esta crisis es total porque abarca su hegemonía y a la humanidad y a la naturaleza. ¿De qué alternativas disponemos para superar este fin de milenio y su hecatombe? Es evidente que estamos viviendo los "tiempos póstumos" o de "filosofía finisecular" de una Modernidad que luce, por otra parte, rebasable desde otra episteme histórico-cultural que reconozca la relación ecosistema del hombre en el conjunto de la diversidad existencial de los seres vivos que pueblan este planeta. Esta otra epistemología que tiene su génesis en la Teoría Crítica y se recrea enAmérica Latina, desde el Sur, se asume desde la praxis de un logos emancipador que fractura los límites hegemónicos del "capitalismo sin fin" y del "colonialismo sin fin", ya que hace posible recuperar desde la "sociología de las emergencias", la presencia de los pueblos milenarios que han logrado la recreación de su habitat a través de una relación simbiótica directa, con los ciclos o procesos de génesis y muerte de la Madre Tierra (Pachamama. La sabiduría ancestral que porta el pensamiento de estos pueblos originarios, expresados por sus tradiciones, ritos, magias, hasta sus representaciones antropomórficas de la realidad, son síntomas de que el ocaso de la civilización, nomuere con Occidente, sino que renace desde el Sur con el "Sumak Kawsay".

  9. Light water reactor program

    Energy Technology Data Exchange (ETDEWEB)

    Franks, S.M.

    1994-12-31

    The US Department of Energy`s Light Water Reactor Program is outlined. The scope of the program consists of: design certification of evolutionary plants; design, development, and design certification of simplified passive plants; first-of-a-kind engineering to achieve commercial standardization; plant lifetime improvement; and advanced reactor severe accident program. These program activities of the Office of Nuclear Energy are discussed.

  10. Space Nuclear Reactor Engineering

    Energy Technology Data Exchange (ETDEWEB)

    Poston, David Irvin [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2017-03-06

    We needed to find a space reactor concept that could be attractive to NASA for flight and proven with a rapid turnaround, low-cost nuclear test. Heat-pipe-cooled reactors coupled to Stirling engines long identified as the easiest path to near-term, low-cost concept.

  11. Reactor Materials Research

    Energy Technology Data Exchange (ETDEWEB)

    Van Walle, E

    2001-04-01

    The activities of the Reactor Materials Research Department of the Belgian Nuclear Research Centre SCK-CEN in 2000 are summarised. The programmes within the department are focussed on studies concerning (1) fusion, in particular mechanical testing; (2) Irradiation Assisted Stress Corrosion Cracking (IASCC); (3) nuclear fuel; and (4) Reactor Pressure Vessel Steel (RPVS)

  12. Nuclear reactor design

    CERN Document Server

    2014-01-01

    This book focuses on core design and methods for design and analysis. It is based on advances made in nuclear power utilization and computational methods over the past 40 years, covering core design of boiling water reactors and pressurized water reactors, as well as fast reactors and high-temperature gas-cooled reactors. The objectives of this book are to help graduate and advanced undergraduate students to understand core design and analysis, and to serve as a background reference for engineers actively working in light water reactors. Methodologies for core design and analysis, together with physical descriptions, are emphasized. The book also covers coupled thermal hydraulic core calculations, plant dynamics, and safety analysis, allowing readers to understand core design in relation to plant control and safety.

  13. Status of French reactors

    Energy Technology Data Exchange (ETDEWEB)

    Ballagny, A. [Commissariat a l`Energie Atomique, Saclay (France)

    1997-08-01

    The status of French reactors is reviewed. The ORPHEE and RHF reactors can not be operated with a LEU fuel which would be limited to 4.8 g U/cm{sup 3}. The OSIRIS reactor has already been converted to LEU. It will use U{sub 3}Si{sub 2} as soon as its present stock of UO{sub 2} fuel is used up, at the end of 1994. The decision to close down the SILOE reactor in the near future is not propitious for the start of a conversion process. The REX 2000 reactor, which is expected to be commissioned in 2005, will use LEU (except if the fast neutrons core option is selected). Concerning the end of the HEU fuel cycle, the best option is reprocessing followed by conversion of the reprocessed uranium to LEU.

  14. Slurry reactor design studies

    Energy Technology Data Exchange (ETDEWEB)

    Fox, J.M.; Degen, B.D.; Cady, G.; Deslate, F.D.; Summers, R.L. (Bechtel Group, Inc., San Francisco, CA (USA)); Akgerman, A. (Texas A and M Univ., College Station, TX (USA)); Smith, J.M. (California Univ., Davis, CA (USA))

    1990-06-01

    The objective of these studies was to perform a realistic evaluation of the relative costs of tublar-fixed-bed and slurry reactors for methanol, mixed alcohols and Fischer-Tropsch syntheses under conditions where they would realistically be expected to operate. The slurry Fischer-Tropsch reactor was, therefore, operated at low H{sub 2}/CO ratio on gas directly from a Shell gasifier. The fixed-bed reactor was operated on 2.0 H{sub 2}/CO ratio gas after adjustment by shift and CO{sub 2} removal. Every attempt was made to give each reactor the benefit of its optimum design condition and correlations were developed to extend the models beyond the range of the experimental pilot plant data. For the methanol design, comparisons were made for a recycle plant with high methanol yield, this being the standard design condition. It is recognized that this is not necessarily the optimum application for the slurry reactor, which is being proposed for a once-through operation, coproducing methanol and power. Consideration is also given to the applicability of the slurry reactor to mixed alcohols, based on conditions provided by Lurgi for an Octamix{trademark} plant using their standard tubular-fixed reactor technology. 7 figs., 26 tabs.

  15. Quelques commentaires sur les personnages de fiction

    Directory of Open Access Journals (Sweden)

    Umberto Eco

    2010-06-01

    Full Text Available L’auteur met en place des observations et développe des analyses sur le statut des personnages de fiction, mettant à contribution les ressources de l’histoire, de la littérature, de la sémiotique, de la logique et de la narratologie. De quelle vie particulière vivent les personnages de roman, qui fait que nous sommes capables de les tenir pour plus réels que des personnages réels, et que nous sommes enclins à éprouver les sentiments qu’ils éprouvent, même si nous savons qu’ils n’existent pas ? Comment ces personnages de fiction existent-ils, selon quelle « partition » leur existence se développe-t-elle au point d’interférer avec la nôtre ? L’interrogation porte sur la nature de ce flux émotionnel qui s’écoule du lecteur vers les personnages de fiction et les investit de valeur, sur ce qui se projette de la vie vers le roman, entraînant avec lui le lecteur qui se trouve de la sorte impliqué malgré lui dans l’histoire, et se trouve pris dans le mécanisme de l’identification et de la vie fictive.Some commentaries about fiction charactersPutting into form a number of observations and developing an analysis on the status of fiction characters, the author draws on resources coming from history, literature, semiotic, logic et narration. What is that particular life lived by fiction characters that enable us to consider them as being more real than real characters, and to experience the feelings that they experience, even though we know that they do not exist? How do these characters exist? In other words, according to what “script” does their existence develop to the point of interfering with ours? The questioning centres on the nature of the emotional flux which flows from the reader towards the fictional characters thus giving them value, and on what it is which is projected from real life towards the novel and which is capable of sweeping up the reader who, without having particularly intended to do

  16. Gas cooled fast reactor

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1972-06-01

    Although most of the development work on fast breeder reactors has been devoted to the use of liquid metal cooling, interest has been expressed for a number of years in alternative breeder concepts using other coolants. One of a number of concepts in which interest has been retained is the Gas-Cooled Fast Reactor (GCFR). As presently envisioned, it would operate on the uranium-plutonium mixed oxide fuel cycle, similar to that used in the Liquid Metal Fast Breeder Reactor (LMFBR), and would use helium gas as the coolant.

  17. Microfluidic electrochemical reactors

    Science.gov (United States)

    Nuzzo, Ralph G [Champaign, IL; Mitrovski, Svetlana M [Urbana, IL

    2011-03-22

    A microfluidic electrochemical reactor includes an electrode and one or more microfluidic channels on the electrode, where the microfluidic channels are covered with a membrane containing a gas permeable polymer. The distance between the electrode and the membrane is less than 500 micrometers. The microfluidic electrochemical reactor can provide for increased reaction rates in electrochemical reactions using a gaseous reactant, as compared to conventional electrochemical cells. Microfluidic electrochemical reactors can be incorporated into devices for applications such as fuel cells, electrochemical analysis, microfluidic actuation, pH gradient formation.

  18. Fast Breeder Reactor studies

    Energy Technology Data Exchange (ETDEWEB)

    Till, C.E.; Chang, Y.I.; Kittel, J.H.; Fauske, H.K.; Lineberry, M.J.; Stevenson, M.G.; Amundson, P.I.; Dance, K.D.

    1980-07-01

    This report is a compilation of Fast Breeder Reactor (FBR) resource documents prepared to provide the technical basis for the US contribution to the International Nuclear Fuel Cycle Evaluation. The eight separate parts deal with the alternative fast breeder reactor fuel cycles in terms of energy demand, resource base, technical potential and current status, safety, proliferation resistance, deployment, and nuclear safeguards. An Annex compares the cost of decommissioning light-water and fast breeder reactors. Separate abstracts are included for each of the parts.

  19. Reactor BR2. Introduction

    Energy Technology Data Exchange (ETDEWEB)

    Gubel, P

    2001-04-01

    The BR2 is a materials testing reactor and is still one of SCK-CEN's important nuclear facilities. After an extensive refurbishment to compensate for the ageing of the installation, the reactor was restarted in April 1997. During the last three years, the availability of the installation was maintained at an average level of 97.6 percent. In the year 2000, the reactor was operated for a total of 104 days at a mean power of 56 MW. In 2000, most irradiation experiments were performed in the CALLISTO PWR loop. The report describes irradiations achieved or under preparation in 2000, including the development of advanced facilities and concept studies for new programmes. An overview of the scientific irradiation programmes as well as of the R and D programme of the BR2 reactor in 2000 is given.

  20. Reactor Neutrino Spectra

    CERN Document Server

    Hayes, A C

    2016-01-01

    We present a review of the antineutrino spectra emitted from reactors. Knowledge of these and their associated uncertainties are crucial for neutrino oscillation studies. The spectra used to-date have been determined by either conversion of measured electron spectra to antineutrino spectra or by summing over all of the thousands of transitions that makeup the spectra using modern databases as input. The uncertainties in the subdominant corrections to beta-decay plague both methods, and we provide estimates of these uncertainties. Improving on current knowledge of the antineutrino spectra from reactors will require new experiments. Such experiments would also address the so-called reactor neutrino anomaly and the possible origin of the shoulder observed in the antineutrino spectra measured in recent high-statistics reactor neutrino experiments.

  1. New reactor type proposed

    CERN Multimedia

    2003-01-01

    "Russian scientists at the Research Institute of Nuclear Power Engineering in Moscow are hoping to develop a new reactor that will use lead and bismuth as fuel instead of uranium and plutonium" (1/2 page).

  2. Réflexions sur la science contemporaine

    CERN Document Server

    Darriulat, Pierre

    2007-01-01

    L'auteur y brosse à grands traits un tableau de la science contemporaine : réductionnisme, déterminisme, abstraction, méthodes, mécanismes de validation et interactions entre observation et théorie... ainsi qu'un portrait de ses artisans et une critique des stéréotypes les plus courants (philistin, iconoclaste, apprenti sorcier...) L'accent est mis sur le fait que la science, dont une des missions consiste à dénoncer les illusions du sens commun, ne poursuit pas une quête de vérité absolue mais se contente aujourd'hui d'une vérité simplement meilleure que celle d'hier. La circularité de la science lui interdit de répondre à des questions essentielles comme «Pourquoi ce monde plutôt que rien ?» Pour tenter d'y répondre, le physicien Pierre Darriulat entreprend, avec candeur et bienveillance, un voyage chez les philosophes. Comment la métaphysique s'évade-t-elle du cercle ? Quelle connaissance autre que scientifique nous propose-t-elle ? La circularité condamnant la science au silence...

  3. Helias reactor studies

    Energy Technology Data Exchange (ETDEWEB)

    Beidler, C.D. [Max-Planck-Institut fuer Plasmaphysik, Garching (Germany); Grieger, G. [Max-Planck-Institut fuer Plasmaphysik, Garching (Germany); Harmeyer, E. [Max-Planck-Institut fuer Plasmaphysik, Garching (Germany); Kisslinger, J. [Max-Planck-Institut fuer Plasmaphysik, Garching (Germany); Karulin, N. [Nuclear Fusion Institute, Moscow (Russian Federation); Maurer, W. [Forschungszentrum Karlsruhe GmbH Technik und Umwelt (Germany); Nuehrenberg, J. [Max-Planck-Institut fuer Plasmaphysik, Garching (Germany); Rau, F. [Max-Planck-Institut fuer Plasmaphysik, Garching (Germany); Sapper, J. [Max-Planck-Institut fuer Plasmaphysik, Garching (Germany); Wobig, H. [Max-Planck-Institut fuer Plasmaphysik, Garching (Germany)

    1995-10-01

    The present status of Helias reactor studies is characterised by the identification and investigation of specific issues which result from the particular properties of this type of stellarator. On the technical side these are issues related to the coil system, while physics studies have concentrated on confinement, alpha-particle behaviour and ignition conditions. The usual assumptions have been made in those fields which are common to all toroidal fusion reactors: blanket and shield, refuelling and exhaust, safety and economic aspects. For blanket and shield sufficient space has been provided, a detailed concept will be developed in future. To date more emphasis has been placed on scoping and parameter studies as opposed to fixing a specific set of parameters and providing a detailed point study. One result of the Helias reactor studies is that physical dimensions are on the same order as those of tokamak reactors. However, it should be noticed that this comparison is difficult in view of the large spectrum of tokamak reactors ranging from a small reactor like Aries, to a large device such as SEAFP. The notion that the large aspect ratio of 10 or more in Helias configurations also leads to large reactors is misleading, since the large major radius of 22 m is compensated by the average plasma radius of 1.8 m and the average coil radius of 5 m. The plasma volume of 1400 m{sup 3} is about the same as the ITER reactor and the magnetic energy of the coil system is about the same or even slightly smaller than envisaged in ITER. (orig.)

  4. Future Reactor Experiments

    OpenAIRE

    He, Miao

    2013-01-01

    The measurement of the neutrino mixing angle $\\theta_{13}$ opens a gateway for the next generation experiments to measure the neutrino mass hierarchy and the leptonic CP-violating phase. Future reactor experiments will focus on mass hierarchy determination and the precision measurement of mixing parameters. Mass hierarchy can be determined from the disappearance of reactor electron antineutrinos based on the interference effect of two separated oscillation modes. Relative and absolute measure...

  5. Reactor Neutrino Experiments

    OpenAIRE

    Cao, Jun

    2007-01-01

    Precisely measuring $\\theta_{13}$ is one of the highest priority in neutrino oscillation study. Reactor experiments can cleanly determine $\\theta_{13}$. Past reactor neutrino experiments are reviewed and status of next precision $\\theta_{13}$ experiments are presented. Daya Bay is designed to measure $\\sin^22\\theta_{13}$ to better than 0.01 and Double Chooz and RENO are designed to measure it to 0.02-0.03. All are heading to full operation in 2010. Recent improvements in neutrino moment measu...

  6. Department of Reactor Technology

    DEFF Research Database (Denmark)

    Risø National Laboratory, Roskilde

    The general development of the Department of Reactor Technology at Risø during 1981 is presented, and the activities within the major subject fields are described in some detail. Lists of staff, publications, and computer programs are included.......The general development of the Department of Reactor Technology at Risø during 1981 is presented, and the activities within the major subject fields are described in some detail. Lists of staff, publications, and computer programs are included....

  7. Moon base reactor system

    Science.gov (United States)

    Chavez, H.; Flores, J.; Nguyen, M.; Carsen, K.

    1989-01-01

    The objective of our reactor design is to supply a lunar-based research facility with 20 MW(e). The fundamental layout of this lunar-based system includes the reactor, power conversion devices, and a radiator. The additional aim of this reactor is a longevity of 12 to 15 years. The reactor is a liquid metal fast breeder that has a breeding ratio very close to 1.0. The geometry of the core is cylindrical. The metallic fuel rods are of beryllium oxide enriched with varying degrees of uranium, with a beryllium core reflector. The liquid metal coolant chosen was natural lithium. After the liquid metal coolant leaves the reactor, it goes directly into the power conversion devices. The power conversion devices are Stirling engines. The heated coolant acts as a hot reservoir to the device. It then enters the radiator to be cooled and reenters the Stirling engine acting as a cold reservoir. The engines' operating fluid is helium, a highly conductive gas. These Stirling engines are hermetically sealed. Although natural lithium produces a lower breeding ratio, it does have a larger temperature range than sodium. It is also corrosive to steel. This is why the container material must be carefully chosen. One option is to use an expensive alloy of cerbium and zirconium. The radiator must be made of a highly conductive material whose melting point temperature is not exceeded in the reactor and whose structural strength can withstand meteor showers.

  8. Stiffness and design for strength of trapezoidal Belleville springs

    DEFF Research Database (Denmark)

    Pedersen, Niels Leergaard; Pedersen, Pauli

    2011-01-01

    in this paper. Finite element results are compared with analytical predictions and critically analysed in terms of the effect of Poisson ratio, overall stiffness, and stress distribution in the spring. This is done in order to verify the range of validity of design standards. Finite element analysis emerges...

  9. Narrow band noise response of a Belleville spring resonator.

    Science.gov (United States)

    Lyon, Richard H

    2013-09-01

    This study of nonlinear dynamics includes (i) an identification of quasi-steady states of response using equivalent linearization, (ii) the temporal simulation of the system using Heun's time step procedure on time domain analytic signals, and (iii) a laboratory experiment. An attempt has been made to select material and measurement parameters so that nearly the same systems are used and analyzed for all three parts of the study. This study illustrates important features of nonlinear response to narrow band excitation: (a) states of response that the system can acquire with transitions of the system between those states, (b) the interaction between the noise source and the vibrating load in which the source transmits energy to or draws energy from the load as transitions occur; (c) the lag or lead of the system response relative to the source as transitions occur that causes the average frequencies of source and response to differ; and (d) the determination of the state of response (mass or stiffness controlled) by observation of the instantaneous phase of the influence function. These analyses take advantage of the use of time domain analytic signals that have a complementary role to functions that are analytic in the frequency domain.

  10. Reactor Safety Planning for Prometheus Project, for Naval Reactors Information

    Energy Technology Data Exchange (ETDEWEB)

    P. Delmolino

    2005-05-06

    The purpose of this letter is to submit to Naval Reactors the initial plan for the Prometheus project Reactor Safety work. The Prometheus project is currently developing plans for cold physics experiments and reactor prototype tests. These tests and facilities may require safety analysis and siting support. In addition to the ground facilities, the flight reactor units will require unique analyses to evaluate the risk to the public from normal operations and credible accident conditions. This letter outlines major safety documents that will be submitted with estimated deliverable dates. Included in this planning is the reactor servicing documentation and shipping analysis that will be submitted to Naval Reactors.

  11. REACTOR GROUT THERMAL PROPERTIES

    Energy Technology Data Exchange (ETDEWEB)

    Steimke, J.; Qureshi, Z.; Restivo, M.; Guerrero, H.

    2011-01-28

    Savannah River Site has five dormant nuclear production reactors. Long term disposition will require filling some reactor buildings with grout up to ground level. Portland cement based grout will be used to fill the buildings with the exception of some reactor tanks. Some reactor tanks contain significant quantities of aluminum which could react with Portland cement based grout to form hydrogen. Hydrogen production is a safety concern and gas generation could also compromise the structural integrity of the grout pour. Therefore, it was necessary to develop a non-Portland cement grout to fill reactors that contain significant quantities of aluminum. Grouts generate heat when they set, so the potential exists for large temperature increases in a large pour, which could compromise the integrity of the pour. The primary purpose of the testing reported here was to measure heat of hydration, specific heat, thermal conductivity and density of various reactor grouts under consideration so that these properties could be used to model transient heat transfer for different pouring strategies. A secondary purpose was to make qualitative judgments of grout pourability and hardened strength. Some reactor grout formulations were unacceptable because they generated too much heat, or started setting too fast, or required too long to harden or were too weak. The formulation called 102H had the best combination of characteristics. It is a Calcium Alumino-Sulfate grout that contains Ciment Fondu (calcium aluminate cement), Plaster of Paris (calcium sulfate hemihydrate), sand, Class F fly ash, boric acid and small quantities of additives. This composition afforded about ten hours of working time. Heat release began at 12 hours and was complete by 24 hours. The adiabatic temperature rise was 54 C which was within specification. The final product was hard and displayed no visible segregation. The density and maximum particle size were within specification.

  12. Scaleable, High Efficiency Microchannel Sabatier Reactor Project

    Data.gov (United States)

    National Aeronautics and Space Administration — A Microchannel Sabatier Reactor System (MSRS) consisting of cross connected arrays of isothermal or graded temperature reactors is proposed. The reactor array...

  13. LMFBR type reactor

    Energy Technology Data Exchange (ETDEWEB)

    Shimizu, Takeshi; Iida, Masaaki; Moriki, Yasuyuki

    1994-10-18

    A reactor core is divided into a plurality of coolants flowrate regions, and electromagnetic pumps exclusively used for each of the flowrate regions are disposed to distribute coolants flowrates in the reactor core. Further, the flowrate of each of the electromagnetic pumps is automatically controlled depending on signals from a temperature detector disposed at the exit of the reactor core, so that the flowrate of the region can be controlled optimally depending on the burning of reactor core fuels. Then, the electromagnetic pumps disposed for every divided region are controlled respectively, so that the coolants flowrate distribution suitable to each of the regions can be attained. Margin for fuel design is decreased, fuels are used effectively, as well as an operation efficiency can be improved. Moreover, since the electromagnetic pump has less flow resistance compared with a mechanical type pump, and flow resistance of the reactor core flowrate control mechanism is eliminated, greater circulating flowrate can be ensured after occurrence of accident in a natural convection using a buoyancy of coolants utilizable for after-heat removal as a driving force. (N.H.).

  14. Reactor Structural Materials: Reactor Pressure Vessel Steels

    Energy Technology Data Exchange (ETDEWEB)

    Chaouadi, R

    2000-07-01

    The objectives of SCK-CEN's R and D programme on Rector Pressure Vessel (RPV) Steels are:(1) to complete the fracture toughness data bank of various reactor pressure vessel steels by using precracked Charpy specimens that were tested statically as well as dynamically; (2) to implement the enhanced surveillance approach in a user-friendly software; (3) to improve the existing reconstitution technology by reducing the input energy (short cycle welding) and modifying the stud geometry. Progress and achievements in 1999 are reported.

  15. Thermionic Reactor Design Studies

    Energy Technology Data Exchange (ETDEWEB)

    Schock, Alfred

    1994-08-01

    Paper presented at the 29th IECEC in Monterey, CA in August 1994. The present paper describes some of the author's conceptual designs and their rationale, and the special analytical techniques developed to analyze their (thermionic reactor) performance. The basic designs, first published in 1963, are based on single-cell converters, either double-ended diodes extending over the full height of the reactor core or single-ended diodes extending over half the core height. In that respect they are similar to the thermionic fuel elements employed in the Topaz-2 reactor subsequently developed in the Soviet Union, copies of which were recently imported by the U.S. As in the Topaz-2 case, electrically heated steady-state performance tests of the converters are possible before fueling.

  16. Nuclear Rocket Engine Reactor

    CERN Document Server

    Lanin, Anatoly

    2013-01-01

    The development of a nuclear rocket engine reactor (NRER ) is presented in this book. The working capacity of an active zone NRER under mechanical and thermal load, intensive neutron fluxes, high energy generation (up to 30 MBT/l) in a working medium (hydrogen) at temperatures up to 3100 K is displayed. Design principles and bearing capacity of reactors area discussed on the basis of simulation experiments and test data of a prototype reactor. Property data of dense constructional, porous thermal insulating and fuel materials like carbide and uranium carbide compounds in the temperatures interval 300 - 3000 K are presented. Technological aspects of strength and thermal strength resistance of materials are considered. The design procedure of possible emergency processes in the NRER is developed and risks for their origination are evaluated. Prospects of the NRER development for pilotless space devices and piloted interplanetary ships are viewed.

  17. Operation of Reactor

    Institute of Scientific and Technical Information of China (English)

    1996-01-01

    3.1 Annual Report of SPR Operation Chu Shaochu Having overseen by National Nuclear Safety Administration and specialists, the reactor restarted up successfully after Safety renovation on April 16, 1996. In August 1996 the normal operation of SPR was approved by the authorities of Naitonal Nuclear Safety Administration. 1 Operation status In 1996, the reactor operated safely for 40 d and the energy released was about 137.3 MW·d. The operation status of SPR is shown in table 1. The reactor started up to higher power (power more than 1 MW) and lower power (for physics experiments) 4 times and 14 times respectively. Measurement of control rod efficiency and other measurement tasks were 2 times and 5 times respectively.

  18. An Overview of Reactor Concepts, a Survey of Reactor Designs.

    Science.gov (United States)

    1985-02-01

    Public Affairs Office and is releasaole to the National Technical Information Services (NTIS). At NTIS, it will be available to the general public...Reactors that use deu- terium (heavy water) as a coolant can use natural uranium as a fuel. The * Canadian reactor, CANDU , utilizes this concept...reactor core at the top and discharged at the Dotton while the reactor is in operation. The discharged fuel can then b inspected to see if it can De used

  19. Oscillatory flow chemical reactors

    Directory of Open Access Journals (Sweden)

    Slavnić Danijela S.

    2014-01-01

    Full Text Available Global market competition, increase in energy and other production costs, demands for high quality products and reduction of waste are forcing pharmaceutical, fine chemicals and biochemical industries, to search for radical solutions. One of the most effective ways to improve the overall production (cost reduction and better control of reactions is a transition from batch to continuous processes. However, the reactions of interests for the mentioned industry sectors are often slow, thus continuous tubular reactors would be impractically long for flow regimes which provide sufficient heat and mass transfer and narrow residence time distribution. The oscillatory flow reactors (OFR are newer type of tube reactors which can offer solution by providing continuous operation with approximately plug flow pattern, low shear stress rates and enhanced mass and heat transfer. These benefits are the result of very good mixing in OFR achieved by vortex generation. OFR consists of cylindrical tube containing equally spaced orifice baffles. Fluid oscillations are superimposed on a net (laminar flow. Eddies are generated when oscillating fluid collides with baffles and passes through orifices. Generation and propagation of vortices create uniform mixing in each reactor cavity (between baffles, providing an overall flow pattern which is close to plug flow. Oscillations can be created by direct action of a piston or a diaphragm on fluid (or alternatively on baffles. This article provides an overview of oscillatory flow reactor technology, its operating principles and basic design and scale - up characteristics. Further, the article reviews the key research findings in heat and mass transfer, shear stress, residence time distribution in OFR, presenting their advantages over the conventional reactors. Finally, relevant process intensification examples from pharmaceutical, polymer and biofuels industries are presented.

  20. Ecoulements denses de grains secs sur plan incliné

    OpenAIRE

    DA CRUZ, F; PROCHNOW, M; AZANZA, E; ROGNON, P; RAGOUILLIAUX, A; TOCQUER, L; MOUCHERONT, P; ROUX, JN; Coussot, P.; CHEVOIR, F

    2003-01-01

    La compréhension des écoulements denses de grains secs a fait de récents progrès grâce aux expériences sur matériaux modèles et aux simulations numériques discrètes. Nous illustrons ces progrès sur l'exemple des écoulements sur plan incliné rugueux. Ils se caractérisent par un seuil d'écoulement dépendant non seulement de l'inclinaison mais aussi de l'épaisseur, et par un régime d'écoulement stationnaire au-dessius du seuil, dont la vitesse s'exprime précisément en fonction de l'épaisseur d'a...

  1. Les entreprises sur les marchés mondiaux

    OpenAIRE

    Bouët, Antoine; Mayer, Thierry

    2003-01-01

    L'ouverture de l'économie française et, plus généralement, son insertion dans le mouvement généralement qualifié de mondialisation sont des préoccupations constantes de l'opinion et ceci a déjà trouvé un écho dans plusieurs numéros consacrés à la question par Économie et Statistique : en 1994, sur le thème « Ouvertures à l'Est et au Sud » ; en 1997, sur « Progrès technique, commerce international et marché du travail » ; et en 1999 sur « Intégration économique et localisation des entreprises ...

  2. Sur les Ecrits de Jean Carbonnier (1908-2003

    Directory of Open Access Journals (Sweden)

    Robert Pageard

    2009-09-01

    Full Text Available Cette centaine de textes divers, présentés et commentés par une équipe de juristes, d’historiens, de sociologues ou d’anthropologues, donne une très vivante vision de la personnalité et des activités d’un penseur qui joua un rôle important dans l’enseignement et l’ évolution de la seconde moitié du XXe siècle.Tout est dit dans cet ouvrage sur l’exceptionnelle érudition de Jean Carbonnier en maints domaines, sur l’élégance et la finesse de sa langue, sur la clarté de son expression. Cette clar...

  3. Perspectives on reactor safety

    Energy Technology Data Exchange (ETDEWEB)

    Haskin, F.E. [New Mexico Univ., Albuquerque, NM (United States). Dept. of Chemical and Nuclear Engineering; Camp, A.L. [Sandia National Labs., Albuquerque, NM (United States)

    1994-03-01

    The US Nuclear Regulatory Commission (NRC) maintains a technical training center at Chattanooga, Tennessee to provide appropriate training to both new and experienced NRC employees. This document describes a one-week course in reactor, safety concepts. The course consists of five modules: (1) historical perspective; (2) accident sequences; (3) accident progression in the reactor vessel; (4) containment characteristics and design bases; and (5) source terms and offsite consequences. The course text is accompanied by slides and videos during the actual presentation of the course.

  4. Reactor Materials Research

    Energy Technology Data Exchange (ETDEWEB)

    Van Walle, E

    2002-04-01

    The activities of SCK-CEN's Reactor Materials Research Department for 2001 are summarised. The objectives of the department are: (1) to evaluate the integrity and behaviour of structural materials used in nuclear power industry; (2) to conduct research to unravel and understand the parameters that determine the material behaviour under or after irradiation; (3) to contribute to the interpretation, the modelling of the material behaviour and to develop and assess strategies for optimum life management of nuclear power plant components. The programmes within the department are focussed on studies concerning (1) Irradiation Assisted Stress Corrosion Cracking (IASCC); (2) nuclear fuel; and (3) Reactor Pressure Vessel Steel.

  5. Sur: uma minoria cosmopolita na periferia ocidental Sur: a cosmopolitan minority on the western periphery

    Directory of Open Access Journals (Sweden)

    Maria Teresa Gramuglio

    2007-06-01

    Full Text Available Este artigo explora as condições e as disposições que tornaram possível o surgimento da revista Sur e a formação do grupo cultural de mesmo nome. Propõe critérios para uma periodização que leve em conta, junto com os indícios materiais, as circunstâncias históricas e culturais cambiantes pelas quais a publicação passou durante sua longa vida (1931-1991. Assinala alguns dos principias temas ideológicos e estéticos que foram abordados em suas páginas. Caracteriza o projeto inicial e as transformações imprimidas pela vontade de sua diretora, Victoria Ocampo, e as mudanças nas relações e problemáticas do campo intelectual.This article explores the conditions and dispositions that enabled the emergence of the magazine Sur and the formation of the cultural group of the same name. It sets out the criteria for a periodization that takes into account, along with material factors, the shifting historical and cultural circumstances experienced by the publication over its 60-year life-span (1931-1991. The text highlights some of the main ideological and aesthetic themes to have filled the magazine's pages. It describes the original project and the transformations introduced by its chief editor, Victoria Ocampo, as well as the changes in the relations and problematics of the intellectual field.

  6. Sur le concept d’engagement

    Directory of Open Access Journals (Sweden)

    Howard S. Becker

    2006-10-01

    Full Text Available Le terme « engagement » connaît un succès grandissant dans les débats sociologiques. Dans ce texte, l’auteur examine les utilisations du concept d'engagement afin de comprendre les raisons de sa popularité grandissante, il signale la nature d'un des mécanismes sociaux auquel le terme se réfère implicitement, et développe une théorie embryonnaire des conditions et des processus sociaux impliqués dans le fonctionnement de ce mécanisme. Étant donné la variété sémantique du terme, il s'avère infructueux de spéculer sur son « véritable » sens. Une des images évoquées par « l'engagement » a été retenue pour en préciser la signification.On the Concept of CommitmentThe term "commitment" is experiencing a growing success in sociological debates. In this article, the author examines the uses of the concept of commitment in order to understand the reasons for its growing popularity. He also points out the nature of one of the social mechanisms to which the term implicitly refers, and he develops a preliminary theory of the social conditions and processes implied in the functioning of this mechanism. Given the semantic variety of the term, it proves useless to speculate on its “true” meaning. In order to clarify the meaning of the term, the author adopts one of the images evoked by “commitment”.Sobre el concepto de compromisoEl término “compromiso” goza de un éxito creciente en los debates sociológicos. En este texto el autor analiza las utilizaciones de este concepto con el fin de comprender las razones de esta creciente popularidad e indica la naturaleza de uno de los mecanismos sociales indicados por ese término, desarrollando seguidamente una teoría embrionaria de las condiciones y de los procesos sociales inherentes a este mecanismo. Teniendo en cuenta la variedad semántica del término es inútil especular acerca de su “verdadero” significado. Con el fin de precisar su significado, el autor

  7. Reactor operation environmental information document

    Energy Technology Data Exchange (ETDEWEB)

    Haselow, J.S.; Price, V.; Stephenson, D.E.; Bledsoe, H.W.; Looney, B.B.

    1989-12-01

    The Savannah River Site (SRS) produces nuclear materials, primarily plutonium and tritium, to meet the requirements of the Department of Defense. These products have been formed in nuclear reactors that were built during 1950--1955 at the SRS. K, L, and P reactors are three of five reactors that have been used in the past to produce the nuclear materials. All three of these reactors discontinued operation in 1988. Currently, intense efforts are being extended to prepare these three reactors for restart in a manner that protects human health and the environment. To document that restarting the reactors will have minimal impacts to human health and the environment, a three-volume Reactor Operations Environmental Impact Document has been prepared. The document focuses on the impacts of restarting the K, L, and P reactors on both the SRS and surrounding areas. This volume discusses the geology, seismology, and subsurface hydrology. 195 refs., 101 figs., 16 tabs.

  8. High Flux Isotope Reactor (HFIR)

    Data.gov (United States)

    Federal Laboratory Consortium — The HFIR at Oak Ridge National Laboratory is a light-water cooled and moderated reactor that is the United States’ highest flux reactor-based neutron source. HFIR...

  9. Reactor operation safety information document

    Energy Technology Data Exchange (ETDEWEB)

    1990-01-01

    The report contains a reactor facility description which includes K, P, and L reactor sites, structures, operating systems, engineered safety systems, support systems, and process and effluent monitoring systems; an accident analysis section which includes cooling system anomalies, radioactive materials releases, and anticipated transients without scram; a summary of onsite doses from design basis accidents; severe accident analysis (reactor core disruption); a description of operating contractor organization and emergency planning; and a summary of reactor safety evolution. (MB)

  10. Thermal Reactor Safety

    Energy Technology Data Exchange (ETDEWEB)

    1980-06-01

    Information is presented concerning fire risk and protection; transient thermal-hydraulic analysis and experiments; class 9 accidents and containment; diagnostics and in-service inspection; risk and cost comparison of alternative electric energy sources; fuel behavior and experiments on core cooling in LOCAs; reactor event reporting analysis; equipment qualification; post facts analysis of the TMI-2 accident; and computational methods.

  11. Chromatographic and Related Reactors.

    Science.gov (United States)

    1988-01-07

    special information about effects of surface heteroge- neity in the methanation reaction. Studies of an efficient multicolumn assembly for measuring...of organic basic catalysts such as pyridine and 4-methylpicoline. It was demonstrated that the chromatographic reactor gave special information about...Programmed Reaction to obtain special information about surface heterogeneity in the methanation reaction. Advantages of stopped flow over steady state

  12. Nuclear Reactors and Technology

    Energy Technology Data Exchange (ETDEWEB)

    Cason, D.L.; Hicks, S.C. [eds.

    1992-01-01

    This publication Nuclear Reactors and Technology (NRT) announces on a monthly basis the current worldwide information available from the open literature on nuclear reactors and technology, including all aspects of power reactors, components and accessories, fuel elements, control systems, and materials. This publication contains the abstracts of DOE reports, journal articles, conference papers, patents, theses, and monographs added to the Energy Science and Technology Database during the past month. Also included are US information obtained through acquisition programs or interagency agreements and international information obtained through the International Energy Agency`s Energy Technology Data Exchange or government-to-government agreements. The digests in NRT and other citations to information on nuclear reactors back to 1948 are available for online searching and retrieval on the Energy Science and Technology Database and Nuclear Science Abstracts (NSA) database. Current information, added daily to the Energy Science and Technology Database, is available to DOE and its contractors through the DOE Integrated Technical Information System. Customized profiles can be developed to provide current information to meet each user`s needs.

  13. Fusion reactor materials

    Energy Technology Data Exchange (ETDEWEB)

    none,

    1989-01-01

    This paper discuses the following topics on fusion reactor materials: irradiation, facilities, test matrices, and experimental methods; dosimetry, damage parameters, and activation calculations; materials engineering and design requirements; fundamental mechanical behavior; radiation effects; development of structural alloys; solid breeding materials; and ceramics.

  14. WATER BOILER REACTOR

    Science.gov (United States)

    King, L.D.P.

    1960-11-22

    As its name implies, this reactor utilizes an aqueous solution of a fissionable element salt, and is also conventional in that it contains a heat exchanger cooling coil immersed in the fuel. Its novelty lies in the utilization of a cylindrical reactor vessel to provide a critical region having a large and constant interface with a supernatant vapor region, and the use of a hollow sleeve coolant member suspended from the cover assembly in coaxial relation with the reactor vessel. Cool water is circulated inside this hollow coolant member, and a gap between its outer wall and the reactor vessel is used to carry off radiolytic gases for recombination in an external catalyst chamber. The central passage of the coolant member defines a reflux condenser passage into which the externally recombined gases are returned and condensed. The large and constant interface between fuel solution and vapor region prevents the formation of large bubbles and minimizes the amount of fuel salt carried off by water vapor, thus making possible higher flux densities, specific powers and power densities.

  15. The First Reactor.

    Science.gov (United States)

    Department of Energy, Washington, DC.

    On December 2, 1942, in a racquet court underneath the West Stands of Stagg Field at the University of Chicago, a team of scientists led by Enrico Fermi created the first controlled, self-sustaining nuclear chain reaction. This updated and revised story of the first reactor (or "pile") is based on postwar interviews (as told to Corbin…

  16. MULTISTAGE FLUIDIZED BED REACTOR

    Science.gov (United States)

    Jonke, A.A.; Graae, J.E.A.; Levitz, N.M.

    1959-11-01

    A multistage fluidized bed reactor is described in which each of a number of stages is arranged with respect to an associated baffle so that a fluidizing gas flows upward and a granular solid downward through the stages and baffles, whereas the granular solid stopsflowing downward when the flow of fluidizing gas is shut off.

  17. Brazilian multipurpose reactor

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2014-07-01

    The Brazilian Multipurpose Reactor (RMB) Project is an action of the Federal Government, through the Ministry of Science Technology and Innovation (MCTI) and has its execution under the responsibility of the Brazilian National Nuclear Energy Commission (CNEN). Within the CNEN, the project is coordinated by the Research and Development Directorate (DPD) and developed through research units of this board: Institute of Nuclear Energy Research (IPEN); Nuclear Engineering Institute (IEN); Centre for Development of Nuclear Technology (CDTN); Regional Center of Nuclear Sciences (CRCN-NE); and Institute of Radiation Protection and Dosimetry (IRD). The Navy Technological Center in Sao Paulo (CTMSP) and also the participation of other research centers, universities, laboratories and companies in the nuclear sector are important and strategic partnerships. The conceptual design and the safety analysis of the reactor and main facilities, related to nuclear and environmental licensing, are performed by technicians of the research units of DPD / CNEN. The basic design was contracted to engineering companies as INTERTHECNE from Brazil and INVAP from Argentine. The research units from DPD/CNEN are also responsible for the design verification on all engineering documents developed by the contracted companies. The construction and installation should be performed by specific national companies and international partnerships. The Nuclear Reactor RMB will be a open pool type reactor with maximum power of 30 MW and have the OPAL nuclear reactor of 20 MW, built in Australia and designed by INVAP, as reference. The RMB reactor core will have a 5x5 configuration, consisting of 23 elements fuels (EC) of U{sub 3}Si{sub 2} dispersion-type Al having a density of up to 3.5 gU/cm{sup 3} and enrichment of 19.75% by weight of {sup 23{sup 5}}U. Two positions will be available in the core for materials irradiation devices. The main objectives of the RMB Reactor and the other nuclear and radioactive

  18. Modeling Chemical Reactors I: Quiescent Reactors

    CERN Document Server

    Michoski, C E; Schmitz, P G

    2010-01-01

    We introduce a fully generalized quiescent chemical reactor system in arbitrary space $\\vdim =1,2$ or 3, with $n\\in\\mathbb{N}$ chemical constituents $\\alpha_{i}$, where the character of the numerical solution is strongly determined by the relative scaling between the local reactivity of species $\\alpha_{i}$ and the local functional diffusivity $\\mathscr{D}_{ij}(\\alpha)$ of the reaction mixture. We develop an operator time-splitting predictor multi-corrector RK--LDG scheme, and utilize $hp$-adaptivity relying only on the entropy $\\mathscr{S}_{\\mathfrak{R}}$ of the reactive system $\\mathfrak{R}$. This condition preserves these bounded nonlinear entropy functionals as a necessarily enforced stability condition on the coupled system. We apply this scheme to a number of application problems in chemical kinetics; including a difficult classical problem arising in nonequilibrium thermodynamics known as the Belousov-Zhabotinskii reaction where we utilize a concentration-dependent diffusivity tensor $\\mathscr{D}_{ij}(...

  19. Remesas internacionales sur-sur y norte-sur en Paraguay: patrones sociodemográficos, destino de los fondos y medios de circulación

    Directory of Open Access Journals (Sweden)

    Pablo Sebastián Gómez

    2016-01-01

    Full Text Available El análisis de las remesas internacionales en los países receptores es un tema ampliamente debatido en la literatura especializada. Sin embargo, en las diferentes perspectivas analíticas y metodológicas no hay consenso sobre la dirección, magnitud e implicancias de estos procesos. Este artículo examina evidencia empírica con base en microdatos de la Encuesta Permanente de Hogares de Paraguay. En primer lugar, se analizan de manera comparativa los patrones sociodemográficos de los hogares receptores del sur y del norte, y de los no perceptores. En segundo lugar, se detallan los mecanismos de circulación y usos de las remesas internacionales en los diferentes circuitos migratorios. Los resultados obtenidos destacan las especificidades de los macrosistemas migratorios vinculados al sur y al norte globales.

  20. Alternative approaches to fusion. [reactor design and reactor physics for Tokamak fusion reactors

    Science.gov (United States)

    Roth, R. J.

    1976-01-01

    The limitations of the Tokamak fusion reactor concept are discussed and various other fusion reactor concepts are considered that employ the containment of thermonuclear plasmas by magnetic fields (i.e., stellarators). Progress made in the containment of plasmas in toroidal devices is reported. Reactor design concepts are illustrated. The possibility of using fusion reactors as a power source in interplanetary space travel and electric power plants is briefly examined.

  1. Reactor monitoring using antineutrino detectors

    Science.gov (United States)

    Bowden, N. S.

    2011-08-01

    Nuclear reactors have served as the antineutrino source for many fundamental physics experiments. The techniques developed by these experiments make it possible to use these weakly interacting particles for a practical purpose. The large flux of antineutrinos that leaves a reactor carries information about two quantities of interest for safeguards: the reactor power and fissile inventory. Measurements made with antineutrino detectors could therefore offer an alternative means for verifying the power history and fissile inventory of a reactor as part of International Atomic Energy Agency (IAEA) and/or other reactor safeguards regimes. Several efforts to develop this monitoring technique are underway worldwide.

  2. Reactor vessel support system. [LMFBR

    Science.gov (United States)

    Golden, M.P.; Holley, J.C.

    1980-05-09

    A reactor vessel support system includes a support ring at the reactor top supported through a box ring on a ledge of the reactor containment. The box ring includes an annular space in the center of its cross-section to reduce heat flow and is keyed to the support ledge to transmit seismic forces from the reactor vessel to the containment structure. A coolant channel is provided at the outside circumference of the support ring to supply coolant gas through the keyways to channels between the reactor vessel and support ledge into the containment space.

  3. Conférence sur l'efficacité

    CERN Document Server

    Jullien, François

    2005-01-01

    Philosophe et sinologue, François Jullien présente ici une conférence qu'il a prononcée auprès de chefs d'entreprise et dans le milieu du management. D'un côté, la conception européenne de l'efficacité est liée à la modélisation comme à la finalité et revendique l'action jusqu'à l'héroïsme ; de l'autre, la pensée chinoise de l'efficience, indirecte et discrète, s'appuie sur le potentiel de situation et induit des " transformations silencieuses ", sans éclat ni même événement. Par-delà cet écart, il s'agira d'interroger la nature de l'effectivité ; ou comment l'intervention humaine réussit à se brancher sur la propension des choses et s'y laisse intégrer. Ce propos se garde donc de séparer tant soit peu l'art d'opérer sur des situations et l'exercice de la philosophie ; en résultent des effets de lecture portant sur l'histoire du XXe siècle ainsi que la géopolitique - et géoéthique - à venir.

  4. Traditional medicine of Baja California Sur (Mexico). I.

    Science.gov (United States)

    Dimayuga, R E; Agundez, J

    1986-08-01

    This study deals with the medicinal use of 30 plants collected in the Municipio de Los Cabos and part of the Municipio de la Paz, Baja California Sur, Mexico. The plants were all taxonomically identified at least to genus level, and their medicinal use, as described to us by elder people, is discussed.

  5. Den sande roman - og Sartres Notes sur 'Madame Bovary'

    DEFF Research Database (Denmark)

    Liisberg, Sune

    2005-01-01

     (forklaring findes i artiklen) om Gustave Flaubert, L'Idiot de la famille, har forfatterens særlige bevågenhed, idet han i lyset af denne torso slutteligt sigter mod en kommentar til Sartres efterladte Notes sur 'Madame Bovary'. For Flaubert var gennembrudsromanen om 'livet i provinsen' udtryk for en...

  6. Élites y sociedad romana de la Meseta sur

    OpenAIRE

    Abascal Palazón, Juan Manuel

    2000-01-01

    Análisis de la composición de la sociedad romana de los territorios de la Meseta sur en época romana, con especial incidencia en la identificación de los grupos familiares que forman las élites urbanas y en la cuantificación de la mano de obra dependiente o manumitida.

  7. Influence de la Chine sur la culture francaise(1)

    Institute of Scientific and Technical Information of China (English)

    SHENDali

    2004-01-01

    I1 serait présomptueux de prétendre que la Chine a eu une influence déterminante sur certains aspects de la culture francaise, tant les civilisations des deux pays, s'avèrent différentes. Par ailleurs, au contraire de l'Europe oc-

  8. Methanogenesis in Thermophilic Biogas Reactors

    DEFF Research Database (Denmark)

    Ahring, Birgitte Kiær

    1995-01-01

    Methanogenesis in thermophilic biogas reactors fed with different wastes is examined. The specific methanogenic activity with acetate or hydrogen as substrate reflected the organic loading of the specific reactor examined. Increasing the loading of thermophilic reactors stabilized the process...... as indicated by a lower concentration of volatile fatty acids in the effluent from the reactors. The specific methanogenic activity in a thermophilic pilot-plant biogas reactor fed with a mixture of cow and pig manure reflected the stability of the reactor. The numbers of methanogens counted by the most...... against Methanothrix soehngenii or Methanothrix CALS-I in any of the thermophilic biogas reactors examined. Studies using 2-14C-labeled acetate showed that at high concentrations (more than approx. 1 mM) acetate was metabolized via the aceticlastic pathway, transforming the methyl-group of acetate...

  9. China: Cooperación Sur-Sur y land grabbing. Un análisis desde las resistencias sociales al proyecto Xai-Xai en Mozambique

    Directory of Open Access Journals (Sweden)

    Sol Mora

    2016-05-01

    Full Text Available Este artículo indaga el modo en que las resistencias sociales manifiestan los vínculos entre la cooperación Sur-Sur de China y el acaparamiento de tierras (land grabbing. Con ese fin, se realiza un estudio de caso del proyecto Xai-Xai en Mozambique. Desde una perspectiva neogramsciana, se argumenta que las resistencias sociales demuestran que la cooperación Sur-Sur de China en el proyecto de Xai-Xai es un discurso que legitima prácticas de acaparamiento de tierras para garantizar su seguridad alimentaria interna.

  10. CARACTERIZACIÓN DEL CONSUMO DE HORTALIZAS EN LAS FAMILIAS DEL SUR-SUR DE COSTA RICA

    Directory of Open Access Journals (Sweden)

    Alexis Villalobos-Monge

    2013-01-01

    Full Text Available El objetivo de este trabajo fue determinar los diferentes aspectos cuantitativos y cualitativos que explican la cultura de consumo actual de hortalizas en las familias residentes en la zona sur-sur de Costa Rica. Este trabajo expone resultados relacionados a la caracterización realizada en el 2011 en familias residentes en la denominada zona sur-sur de Costa Rica sobre la cultura de consumo de productos hortícolas. Se aplicaron cuestionarios a una muestra estratificada de familias; lo que permitió establecer la valoración de los precios de mercado, por parte de las familias, para consumir estos alimentos, donde se determinó un valor máximo de US$1,74 millones por semana. Los principales rubros de consumo de acuerdo al valor pagado fueron el tomate, la papa, el plátano, la cebolla y el brócoli, para citar los cinco principales. También fue posible establecer valoraciones cualitativas sobre el consumo de estos productos; por ejemplo se determinó que para el 71,2% de las familias, la frescura representa la característica de mayor valor, además, el principal sitio donde los núcleos familiares realizan las compras de estos alimentos corresponde a supermercados (38,4% de los casos.

  11. MEANS FOR COOLING REACTORS

    Science.gov (United States)

    Wheeler, J.A.

    1957-11-01

    A design of a reactor is presented in which the fuel elements may be immersed in a liquid coolant when desired without the necessity of removing them from the reactor structure. The fuel elements, containing the fissionable material are in plate form and are disposed within spaced slots in a moderator material, such as graphite to form the core. Adjacent the core is a tank containing the liquid coolant. The fuel elements are mounted in spaced relationship on a rotatable shaft which is located between the core and the tank so that by rotation of the shaft the fuel elements may be either inserted in the slots in the core to sustain a chain reaction or immersed in the coolant.

  12. Compact fusion reactors

    CERN Document Server

    CERN. Geneva

    2015-01-01

    Fusion research is currently to a large extent focused on tokamak (ITER) and inertial confinement (NIF) research. In addition to these large international or national efforts there are private companies performing fusion research using much smaller devices than ITER or NIF. The attempt to achieve fusion energy production through relatively small and compact devices compared to tokamaks decreases the costs and building time of the reactors and this has allowed some private companies to enter the field, like EMC2, General Fusion, Helion Energy, Lawrenceville Plasma Physics and Lockheed Martin. Some of these companies are trying to demonstrate net energy production within the next few years. If they are successful their next step is to attempt to commercialize their technology. In this presentation an overview of compact fusion reactor concepts is given.

  13. Reactor Neutrino Spectra

    OpenAIRE

    Hayes, A. C.; Vogel, Petr

    2016-01-01

    We present a review of the antineutrino spectra emitted from reactors. Knowledge of these spectra and their associated uncertainties is crucial for neutrino oscillation studies. The spectra used to date have been determined either by converting measured electron spectra to antineutrino spectra or by summing over all of the thousands of transitions that make up the spectra, using modern databases as input. The uncertainties in the subdominant corrections to β-decay plague both methods, and we ...

  14. REACTOR MODERATOR STRUCTURE

    Science.gov (United States)

    Greenstreet, B.L.

    1963-12-31

    A system for maintaining the alignment of moderator block structures in reactors is presented. Integral restraining grids are placed between each layer of blocks in the moderator structure, at the top of the uppermost layer, and at the bottom of the lowermost layer. Slots are provided in the top and bottom surfaces of the moderator blocks so as to provide a keying action with the grids. The grids are maintained in alignment by vertical guiding members disposed about their peripheries. (AEC)

  15. BOILER-SUPERHEATED REACTOR

    Science.gov (United States)

    Heckman, T.P.

    1961-05-01

    A nuclear power reactor of the type in which a liquid moderator-coolant is transformed by nuclear heating into a vapor that may be used to drive a turbo- generator is described. The core of this reactor comprises a plurality of freely suspended tubular fuel elements, called fuel element trains, within which nonboiling pressurized liquid moderator-coolant is preheated and sprayed through orifices in the walls of the trains against the outer walls thereof to be converted into vapor. Passage of the vapor ovcr other unwetted portions of the outside of the fuel elements causes the steam to be superheated. The moderatorcoolant within the fuel elements remains in the liqUid state, and that between the fuel elements remains substantiaily in the vapor state. A unique liquid neutron-absorber control system is used. Advantages expected from the reactor design include reduced fuel element failure, increased stability of operation, direct response to power demand, and circulation of a minimum amount of liquid moderatorcoolant. (A.G.W.)

  16. Nuclear research reactors in Brazil

    Energy Technology Data Exchange (ETDEWEB)

    Cota, Anna Paula Leite; Mesquita, Amir Zacarias, E-mail: aplc@cdtn.b, E-mail: amir@cdtn.b [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil)

    2011-07-01

    The rising concerns about global warming and energy security have spurred a revival of interest in nuclear energy, giving birth to a 'nuclear power renaissance' in several countries in the world. Particularly in Brazil, in the recent years, the nuclear power renaissance can be seen in the actions that comprise its nuclear program, summarily the increase of the investments in nuclear research institutes and the government target to design and build the Brazilian Multipurpose research Reactor (BMR). In the last 50 years, Brazilian research reactors have been used for training, for producing radioisotopes to meet demands in industry and nuclear medicine, for miscellaneous irradiation services and for academic research. Moreover, the research reactors are used as laboratories to develop technologies in power reactors, which are evaluated today at around 450 worldwide. In this application, those reactors become more viable in relation to power reactors by the lowest cost, by the operation at low temperatures and, furthermore, by lower demand for nuclear fuel. In Brazil, four research reactors were installed: the IEA-R1 and the MB-01 reactors, both at the Instituto de Pesquisas Energeticas Nucleares (IPEN, Sao Paulo); the Argonauta, at the Instituto de Engenharia Nuclear (IEN, Rio de Janeiro) and the IPR-R1 TRIGA reactor, at the Centro de Desenvolvimento da Tecnologia Nuclear (CDTN, Belo Horizonte). The present paper intends to enumerate the characteristics of these reactors, their utilization and current academic research. Therefore, through this paper, we intend to collaborate on the BMR project. (author)

  17. Thermionic Reactor Design Studies

    Energy Technology Data Exchange (ETDEWEB)

    Schock, Alfred

    1994-06-01

    During the 1960's and early 70's the author performed extensive design studies, analyses, and tests aimed at thermionic reactor concepts that differed significantly from those pursued by other investigators. Those studies, like most others under Atomic Energy Commission (AEC and DOE) and the National Aeronautics and Space Administration (NASA) sponsorship, were terminated in the early 1970's. Some of this work was previously published, but much of it was never made available in the open literature. U.S. interest in thermionic reactors resumed in the early 80's, and was greatly intensified by reports about Soviet ground and flight tests in the late 80's. This recent interest resulted in renewed U.S. thermionic reactor development programs, primarily under Department of Defense (DOD) and Department of Energy (DOE) sponsorship. Since most current investigators have not had an opportunity to study all of the author's previous work, a review of the highlights of that work may be of value to them. The present paper describes some of the author's conceptual designs and their rationale, and the special analytical techniques developed to analyze their performance. The basic designs, first published in 1963, are based on single-cell converters, either double-ended diodes extending over the full height of the reactor core or single-ended diodes extending over half the core height. In that respect they are similar to the thermionic fuel elements employed in the Topaz-2 reactor subsequently developed in the Soviet Union, copies of which were recently imported by the U.S. As in the Topaz-2 case, electrically heated steady-state performance tests of the converters are possible before fueling. Where the author's concepts differed from the later Topaz-2 design was in the relative location of the emitter and the collector. Placing the fueled emitter on the outside of the cylindrical diodes permits much higher axial conductances to reduce ohmic

  18. Sur un deplacement de valeurs: traire et tirer

    Directory of Open Access Journals (Sweden)

    André Burger

    1972-12-01

    Full Text Available L'étymologie de firer est inconnue. Celie que le regretté W. von Wart burg a ern pouvoir avancer est inacceptable: firer serait sorti de marty rier par la grâce d'une fausse coupure mar tirier. Il est plus qu'improbable que cette «étymologie populaire» eût pu se produire si la langue ne possédait pas au préalable un verbe tirier. Au surplus aucun fait n'appuie cette hypothèse. Le FEW, t. VI, 1, p. 396, donne bien pour firer le sens de «torturer sur un treteam>, au XIIIe siècle, et p. 403, «démembrer en faisant tirer les quatre membles par des chevaux» et «torturer (qn en l'étendant sur un tréteau” au XIVe siècle; ces sens sont évidemment trop tardifs pour permettre des conclusions sur l'origine de firer, d'autant plus qu'ils s'expliquent sans peine par la valeur normale du mot, attesté dès la Chanson de Roland, sans aucun rapport avec martirie, mot savant de clerc, qui, dans le même texte s'applique deux fois sur quatre exemples aux Sarrasins, vv. 501 et 1467, où il ne signifie pas «martyre» mais <sur son étymologie et non sur les textes, que tirer aurait à l'origine »einen starken affektiven unterton« (FEW XIII, 2, p. 185. L'étude des exemples de la Chanson de Roland, confrontés avec ceux de traire, nons amènera à une conclusion toute différente.

  19. Turning points in reactor design

    Energy Technology Data Exchange (ETDEWEB)

    Beckjord, E.S.

    1995-09-01

    This article provides some historical aspects on nuclear reactor design, beginning with PWR development for Naval Propulsion and the first commercial application at Yankee Rowe. Five turning points in reactor design and some safety problems associated with them are reviewed: (1) stability of Dresden-1, (2) ECCS, (3) PRA, (4) TMI-2, and (5) advanced passive LWR designs. While the emphasis is on the thermal-hydraulic aspects, the discussion is also about reactor systems.

  20. Fast reactor programme in India

    Indian Academy of Sciences (India)

    P Chellapandi; P R Vasudeva Rao; Prabhat Kumar

    2015-09-01

    Role of fast breeder reactor (FBR) in the Indian context has been discussed with appropriate justification. The FBR programme since 1985 till 2030 is highlighted focussing on the current status and future direction of fast breeder test reactor (FBTR), prototype fast breeder reactor (PFBR) and FBR-1 and 2. Design and technological challenges of PFBR and design and safety targets with means to achieve the same are the major highlights of this paper.

  1. Acceptability of reactors in space

    Energy Technology Data Exchange (ETDEWEB)

    Buden, D.

    1981-04-01

    Reactors are the key to our future expansion into space. However, there has been some confusion in the public as to whether they are a safe and acceptable technology for use in space. The answer to these questions is explored. The US position is that when reactors are the preferred technical choice, that they can be used safely. In fact, it dies not appear that reactors add measurably to the risk associated with the Space Transportation System.

  2. Spiral-shaped disinfection reactors

    KAUST Repository

    Ghaffour, Noreddine

    2015-08-20

    This disclosure includes disinfection reactors and processes for the disinfection of water. Some disinfection reactors include a body that defines an inlet, an outlet, and a spiral flow path between the inlet and the outlet, in which the body is configured to receive water and a disinfectant at the inlet such that the water is exposed to the disinfectant as the water flows through the spiral flow path. Also disclosed are processes for disinfecting water in such disinfection reactors.

  3. Hydrogen Production in Fusion Reactors

    OpenAIRE

    Sudo, S.; Tomita, Y.; Yamaguchi, S.; Iiyoshi, A.; Momota, H; Motojima, O.; Okamoto, M.; Ohnishi, M.; Onozuka, M; Uenosono, C.

    1993-01-01

    As one of methods of innovative energy production in fusion reactors without having a conventional turbine-type generator, an efficient use of radiation produced in a fusion reactor with utilizing semiconductor and supplying clean fuel in a form of hydrogen gas are studied. Taking the candidates of reactors such as a toroidal system and an open system for application of the new concepts, the expected efficiency and a concept of plant system are investigated.

  4. Neutrino Oscillation Studies with Reactors

    CERN Document Server

    Vogel, Petr; Zhang, Chao

    2015-01-01

    Nuclear reactors are one of the most intense, pure, controllable, cost-effective, and well-understood sources of neutrinos. Reactors have played a major role in the study of neutrino oscillations, a phenomenon that indicates that neutrinos have mass and that neutrino flavors are quantum mechanical mixtures. Over the past several decades reactors were used in the discovery of neutrinos, were crucial in solving the solar neutrino puzzle, and allowed the determination of the smallest mixing angle $\\theta_{13}$. In the near future, reactors will help to determine the neutrino mass hierarchy and to solve the puzzling issue of sterile neutrinos.

  5. Sur le nombre de points rationnels des variétés abéliennes et des Jacobiennes sur les corps finis

    DEFF Research Database (Denmark)

    Aubry, Yves; Haloui, Safia; Lachaud, Gilles

    2012-01-01

    Nous établissons de nouvelles majorations et minorations pour le nombre de points rationnels des variétés abéliennes et des Jacobiennes sur un corps fini. Nous déterminons de plus les nombres maximum et minimum de points rationnels des surfaces Jacobiennes sur un corps fini donné. We give upper a...

  6. Etude des effets du martelage repetitif sur les contraintes residuelles

    Science.gov (United States)

    Hacini, Lyes

    L'assemblage par soudage peut engendrer des contraintes residuelles. Ces contraintes provoquent des fissurations prematurees et un raccourcissement de la duree de vie des composants. Dans ce contexte, le martelage robotise est utilise pour relaxer ces contraintes residuelles. Trois volets sont presentes: le premier est l'evaluation des effets des impacts unitaires repetes sur le champ de contraintes developpe dans des plaques d'acier inoxydable austenitique 304L vierges ou contenant des contraintes residuelles initiales. Dans la deuxieme partie de ce projet, le martelage est applique grace au robot SCOMPI. Les contraintes residuelles induites et relaxees par martelage sont ensuite mesurees par la methode des contours, qui a ete adaptee a cet effet. Dans la troisieme partie, le martelage est modelise par la methode des elements finis. Un modele axisymetrique developpe grace au logiciel ANSYS permet de simuler des impacts repetes d'un marteau elastique sur une plaque ayant un comportement elastoplastique.

  7. Science et débat public sur le vivant

    Directory of Open Access Journals (Sweden)

    Piron Florence

    2015-01-01

    Full Text Available Quels sont les repères éthiques et politiques que les sociétés se donnent pour respecter la vie et le vivant selon leur culture ? D’où viennent les débats et les dissensus? Au-delà des débats de société suscités par le vivant aujourd’hui, il est essentiel de mettre au jour les présupposés épistémologiques qui, en plus des politiques scientifiques, orientent les recherches sur le vivant qui, ensuite, sont mobilisées comme moyen de légitimation des arguments dans ces débats. La science apparaît alors comme une institution non neutre, inscrite dans la culture, qui influence les débats publics sur le vivant, au lieu de seulement les éclairer.

  8. Discours de gangs afro-américains sur Internet

    OpenAIRE

    Goudet, Laura Gabrielle

    2015-01-01

    Cet article est une étude de cinquante-cinq pages de profils de membres autoproclamés de gangs (Bloods et Crips) sur Black Planet (BP), le plus important réseau social afro-américain. Ces profils partagent des caractéristiques communes, comme la représentation de son propre gang (« repping »), et l’insulte du gang rival (« dissing »). L’examen de la projection de leur page dans un écosystème plus important (en- et hors ligne, sur BP et d’autres plateformes) et une analyse sémiotique des éléme...

  9. Playa de sol: La cabaña del sur

    Directory of Open Access Journals (Sweden)

    Adel López Gómez

    1964-01-01

    Full Text Available La "Cabaña del Sur" no ha cambiado nada durante mis dos años de ausencia. Ahí está, en la playa de Bocagrande, con su alta techumbre de paja, a cuarenta o cincuenta metros del mar, con su pequeño mirador y sus ventanas abiertas sobre la inmensidad del Pacífico, al final del pequeño caserío negro.

  10. Traditional medicine of Baja California Sur (Mexico). II.

    Science.gov (United States)

    Encarnacion Dimayuga, R; Fort Murillo, R; Luis Pantoja, M

    1987-08-01

    Continuing our studies of traditional medicine, as used in rural areas of Baja California Sur, now we wish to report on the medicinal uses of 49 more plants. Some of the more complex recipes of these medicinal plants, are discussed in the present paper. The information presented here was collected in the Municipio of Los Cabos and part of the Municipio of La Paz, B.C.S., Mexico.

  11. Note sur le bassin Houiller de Sabero, Espagne

    NARCIS (Netherlands)

    Henkes, H.

    1961-01-01

    En Espagne septentrionale, dans la province de León, à une dizaine de kilomètres au NO de la ville de Cistierna, s’étend un bassin houiller entre le Rio Porma et le Rio Esla, perpendiculaire à ces fleuves et avec la ville de Sabero au centre. La situation précise peut être retrouvée sur les feuilles

  12. Bilan du programme autrichien de recherche sur les paysages

    Directory of Open Access Journals (Sweden)

    Karolina Begusch-Pfefferkorn

    2009-03-01

    Full Text Available Austrian Landscape Research, a programme of the Austrian Ministry of Science, has created scientific foundations for the sustainable development of Austrian landscapes and regions (plus bordering regions. Landscapes and regions were to be explored from different angles; implementing the research findings was to be part of the research work. The programme was designed to make room for science open to society, for unconventional ideas, methods, and courses of action. Programmatic targets and research principles supported this intent. The results of the programme met with national and international approval. The ALR knowledge balance is an attempt at presenting and assessing the achievements of this comprehensive contract research programme.Le programme du Ministère autrichien des Sciences, intitulé « Recherche sur le paysage autrichien », visait à construire les fondements scientifiques d’un développement durable des paysages et des régions de l’Autriche et des territoires limitrophes. Les paysages et les régions ont été étudiés selon différentes approches disciplinaires et la mise en pratique des résultats de cette étude était partie prenante du programme de recherche. La vocation de ce programme était de faire la place à une science ouverte sur la société, à des idées, méthodes et pratiques non conventionnelles. Les objectifs du programme et les principes de recherche vont dans le sens de ces exigences. Les résultats du programme ont été reconnus sur le plan national et international. Le bilan des connaissances du programme de recherche sur le paysage autrichien (KLF a pour but de présenter et d’évaluer les performances de ce vaste programme de recherche.

  13. Recherches sur la flore pliocène de Java

    NARCIS (Netherlands)

    Crié, M.L.

    1888-01-01

    En publiant ces premières recherches sur les plantes pliocènes de Java, c’est un plaisir pour moi de remercier le savant directeur du musée géologique de Leyde, monsieur K. Martin, qui m’a fait l’honneur de m’en confier l’étude. Un tel sujet ne pouvait être traité prématurément, et j’ai dû recherche

  14. FAST NEUTRONIC REACTOR

    Science.gov (United States)

    Snell, A.H.

    1957-12-01

    This patent relates to a reactor and process for carrying out a controlled fast neutron chain reaction. A cubical reactive mass, weighing at least 920 metric tons, of uranium metal containing predominantly U/sup 238/ and having a U/sup 235/ content of at least 7.63% is assembled and the maximum neutron reproduction ratio is limited to not substantially over 1.01 by insertion and removal of a varying amount of boron, the reactive mass being substantially freed of moderator.

  15. Biparticle fluidized bed reactor

    Science.gov (United States)

    Scott, C.D.

    1993-12-14

    A fluidized bed reactor system which utilizes a fluid phase, a retained fluidized primary particulate phase, and a migratory second particulate phase is described. The primary particulate phase is a particle such as a gel bead containing an immobilized biocatalyst. The secondary particulate phase, continuously introduced and removed in either cocurrent or countercurrent mode, acts in a secondary role such as a sorbent to continuously remove a product or by-product constituent from the fluid phase. Introduction and removal of the sorbent phase is accomplished through the use of feed screw mechanisms and multivane slurry valves. 3 figures.

  16. L'Avenir de la Vie sur la Terre

    CERN Document Server

    CERN. Geneva

    2007-01-01

    Notre planète va mal : réchauffement climatique, épuisement des ressources naturelles, pollutions des sols et de l'eau provoquées par les industries civiles et guerrières, disparité des richesses, malnutrition des hommes, taux d'extinction effarant des espèces vivantes, etc. La situation est-elle vraiment dramatique ? Que penser des thèses qui contestent ce pessimisme ? À partir des données scientifiques les plus crédibles - et de leurs incertitudes -, Hubert Reeves dresse un bilan précis des menaces qui pèsent sur la planète. Son diagnostic est alarmant : si la vie sur Terre est robuste, c'est l'avenir de l'espèce humaine qui est en cause. Le sort de l'aventure humaine, entamée il y a des millions d'années, va-t-il se jouer en l'espace de quelques décennies ? Notre avenir est entre nos mains. Il faut réagir, et vite, avant qu'il ne soit trop tard. Auteur de nombreux ouvrages sur l'odyssée cosmique tel Patience dans l'azur ou Poussières d'étoiles, Hubert Reeves est astrophysicien et dire...

  17. La vérite sur ce qui nous motive

    CERN Document Server

    Pink, Daniel H

    2011-01-01

    Voici enfin la traduction française du best-seller international DRIVE ! Qu'est-ce qui nous motive vraiment ? Dans quels cas sommes-nous les plus performants et les plus enthousiastes ? La plupart d'entre nous sommes persuadés que les récompenses (salaire, primes...) sont notre meilleure motivation. La logique de la carotte et du bâton finalement... Et si nous faisions fausse route ? En s'appuyant sur quatre décennies d'études scientifiques et psychologiques sur la motivation humaine, Pink démontre que les entreprises dirigent très mal leurs équipes avec d'énormes conséquences sur notre vie (absence d'ambition, lassitude, morosité). Le secret de la performance (et de la satisfaction) dans les entreprises, l'enseignement ou dans notre vie personnelle , c'est le besoin profondément humain de diriger sa propre vie, d'apprendre, de créer de nouvelles choses et de s'améliorer. Dans ce livre, Pink examine les 3 éléments de la motivation, l'autonomie, la maîtrise et le besoin de donner un sens ...

  18. Licensed reactor nuclear safety criteria applicable to DOE reactors

    Energy Technology Data Exchange (ETDEWEB)

    1991-04-01

    The Department of Energy (DOE) Order DOE 5480.6, Safety of Department of Energy-Owned Nuclear Reactors, establishes reactor safety requirements to assure that reactors are sited, designed, constructed, modified, operated, maintained, and decommissioned in a manner that adequately protects health and safety and is in accordance with uniform standards, guides, and codes which are consistent with those applied to comparable licensed reactors. This document identifies nuclear safety criteria applied to NRC (Nuclear Regulatory Commission) licensed reactors. The titles of the chapters and sections of USNRC Regulatory Guide 1.70, Standard Format and Content of Safety Analysis Reports for Nuclear Power Plants, Rev. 3, are used as the format for compiling the NRC criteria applied to the various areas of nuclear safety addressed in a safety analysis report for a nuclear reactor. In each section the criteria are compiled in four groups: (1) Code of Federal Regulations, (2) US NRC Regulatory Guides, SRP Branch Technical Positions and Appendices, (3) Codes and Standards, and (4) Supplemental Information. The degree of application of these criteria to a DOE-owned reactor, consistent with their application to comparable licensed reactors, must be determined by the DOE and DOE contractor.

  19. Reactor Physics Analysis Models for a CANDU Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Hang Bok

    2007-10-15

    Canada deuterium uranium (CANDU) reactor physics analysis is typically performed in three steps. At first, macroscopic cross-sections of the reference lattice is produced by modeling the reference fuel channel. Secondly macroscopic cross-sections of reactivity devices in the reactor are generated. The macroscopic cross-sections of a reactivity device are calculated as incremental cross-sections by subtracting macroscopic cross-sections of a three-dimensional lattice without reactivity device from those of a three-dimensional lattice with a reactivity device. Using the macroscopic cross-sections of the reference lattice and incremental cross-sections of the reactivity devices, reactor physics calculations are performed. This report summarizes input data of typical CANDU reactor physics codes, which can be utilized for the future CANDU reactor physics analysis.

  20. Effets des electrons secondaires sur l'ADN

    Science.gov (United States)

    Boudaiffa, Badia

    Les interactions des electrons de basse energie (EBE) representent un element important en sciences des radiations, particulierement, les sequences se produisant immediatement apres l'interaction de la radiation ionisante avec le milieu biologique. Il est bien connu que lorsque ces radiations deposent leur energie dans la cellule, elles produisent un grand nombre d'electrons secondaires (4 x 104/MeV), qui sont crees le long de la trace avec des energies cinetiques initiales bien inferieures a 20 eV. Cependant, il n'y a jamais eu de mesures directes demontrant l'interaction de ces electrons de tres basse energie avec l'ADN, du principalement aux difficultes experimentales imposees par la complexite du milieu biologique. Dans notre laboratoire, les dernieres annees ont ete consacrees a l'etude des phenomenes fondamentaux induits par impact des EBE sur differentes molecules simples (e.g., N2, CO, O2, H2O, NO, C2H 4, C6H6, C2H12) et quelques molecules complexes dans leur phase solide. D'autres travaux effectues recemment sur des bases de l'ADN et des oligonucleotides ont montre que les EBE produisent des bris moleculaires sur les biomolecules. Ces travaux nous ont permis d'elaborer des techniques pour mettre en evidence et comprendre les interactions fondamentales des EBE avec des molecules d'interet biologique, afin d'atteindre notre objectif majeur d'etudier l'effet direct de ces particules sur la molecule d'ADN. Les techniques de sciences des surfaces developpees et utilisees dans les etudes precitees peuvent etre etendues et combinees avec des methodes classiques de biologie pour etudier les dommages de l'ADN induits par l'impact des EBE. Nos experiences ont montre l'efficacite des electrons de 3--20 eV a induire des coupures simple et double brins dans l'ADN. Pour des energies inferieures a 15 eV, ces coupures sont induites par la localisation temporaire d'un electron sur une unite moleculaire de l'ADN, ce qui engendre la formation d'un ion negatif transitoire

  1. Brookhaven leak reactor to close

    CERN Multimedia

    MacIlwain, C

    1999-01-01

    The DOE has announced that the High Flux Beam Reactor at Brookhaven is to close for good. Though the news was not unexpected researchers were angry the decision had been taken before the review to assess the impact of reopening the reactor had been concluded (1 page).

  2. Thermochemical reactor systems and methods

    Energy Technology Data Exchange (ETDEWEB)

    Lipinski, Wojciech; Davidson, Jane Holloway; Chase, Thomas Richard

    2016-11-29

    Thermochemical reactor systems that may be used to produce a fuel, and methods of using the thermochemical reactor systems, utilizing a reactive cylindrical element, an optional energy transfer cylindrical element, an inlet gas management system, and an outlet gas management system.

  3. Chemical-vapor-deposition reactor

    Science.gov (United States)

    Chern, S.

    1979-01-01

    Reactor utilizes multiple stacked trays compactly arranged in paths of horizontally channeled reactant gas streams. Design allows faster and more efficient deposits of film on substrates, and reduces gas and energy consumption. Lack of dead spots that trap reactive gases reduces reactor purge time.

  4. Antineutrino Monitoring of Thorium Reactors

    CERN Document Server

    Akindele, Oluwatomi A; Norman, Eric B

    2015-01-01

    Various groups have demonstrated that antineutrino monitoring can be successful in assessing the plutonium content in water-cooled nuclear reactors for nonproliferation applications. New reactor designs and concepts incorporate nontraditional fuels types and chemistry. Understanding how these properties affect the antineutrino emission from a reactor can extend the applicability of antineutrino monitoring.Thorium molten salt reactors (MSR) breed U-233, that if diverted constitute an IAEA direct use material. The antineutrino spectrum from the fission of U-233 has been determined, the feasibility of detecting the diversion of a significant quantity, 8 kg of U-233, within the IAEA timeliness goal of 30 days has been evaluated. The antineutrino emission from a thorium reactor operating under normal conditions is compared to a diversion scenario at a 25 meter standoff by evaluating the daily antineutrino count rate and the energy spectrum of the detected antineutrinos. It was found that the diversion of a signifi...

  5. Engineering reactors for catalytic reactions

    Indian Academy of Sciences (India)

    Vivek V Ranade

    2014-03-01

    Catalytic reactions are ubiquitous in chemical and allied industries. A homogeneous or heterogeneous catalyst which provides an alternative route of reaction with lower activation energy and better control on selectivity can make substantial impact on process viability and economics. Extensive studies have been conducted to establish sound basis for design and engineering of reactors for practising such catalytic reactions and for realizing improvements in reactor performance. In this article, application of recent (and not so recent) developments in engineering reactors for catalytic reactions is discussed. Some examples where performance enhancement was realized by catalyst design, appropriate choice of reactor, better injection and dispersion strategies and recent advances in process intensification/ multifunctional reactors are discussed to illustrate the approach.

  6. Unsteady processes in catalytic reactors

    Energy Technology Data Exchange (ETDEWEB)

    Matros, Yu.Sh.

    1985-01-01

    In recent years a realization has occurred that reaction and reactor dynamics must be considered when designing and operating catalytic reactors. In this book, the author has focussed on both the processes occurring on individual porous-catalyst particles as well as the phenomena displayed by collections of these particles in fixed-bed reactors. The major topics discussed include the effects of unsteady-state heat and mass transfer, the influence of inhomogeneities and stagnant regions in fixed beds, and reactor operation during forced cycling of operating conditions. Despite the title of the book, attention is also paid to the determination of the number and stability of fixed-bed steady states, with the aim of describing the possibility of controlling reactors at unstable steady states. However, this development is somewhat dated, given the recent literature on multiplicity phenomena and process control.

  7. A model of reactor kinetics

    Energy Technology Data Exchange (ETDEWEB)

    Thompson, A.S.; Thompson, B.R.

    1988-09-01

    The analytical model of nuclear reactor transients, incorporating both mechanical and nuclear effects, simulates reactor kinetics. Linear analysis shows the stability borderline for small power perturbations. In a stable system, initial power disturbances die out with time. With an unstable combination of nuclear and mechanical characteristics, initial disturbances persist and may increase with time. With large instability, oscillations of great magnitude occur. Stability requirements set limits on the power density at which particular reactors can operate. The limiting power density depends largely on the product of two terms: the fraction of delayed neutrons and the frictional damping of vibratory motion in reactor core components. As the fraction of delayed neutrons is essentially fixed, mechanical damping largely determines the maximum power density. A computer program, based on the analytical model, calculates and plots reactor power as a nonlinear function of time in response to assigned values of mechanical and nuclear characteristics.

  8. Metallic fuels for advanced reactors

    Science.gov (United States)

    Carmack, W. J.; Porter, D. L.; Chang, Y. I.; Hayes, S. L.; Meyer, M. K.; Burkes, D. E.; Lee, C. B.; Mizuno, T.; Delage, F.; Somers, J.

    2009-07-01

    In the framework of the Generation IV Sodium Fast Reactor Program, the Advanced Fuel Project has conducted an evaluation of the available fuel systems supporting future sodium cooled fast reactors. This paper presents an evaluation of metallic alloy fuels. Early US fast reactor developers originally favored metal alloy fuel due to its high fissile density and compatibility with sodium. The goal of fast reactor fuel development programs is to develop and qualify a nuclear fuel system that performs all of the functions of a conventional fast spectrum nuclear fuel while destroying recycled actinides. This will provide a mechanism for closure of the nuclear fuel cycle. Metal fuels are candidates for this application, based on documented performance of metallic fast reactor fuels and the early results of tests currently being conducted in US and international transmutation fuel development programs.

  9. La gestion des reseaux IP basee sur les technologies Web et le modele push

    OpenAIRE

    1999-01-01

    La gestion des rseaux IP est actuellement fonde sur le protocole SNMP, ainsi que sur des plateformes de gestion coteuses implmentant le paradigme gestionnaire-agent du cadre de gestion SNMP. Cette gestion repose sur deux types de transfert de donnes: un protocole de type requte/rponse, pour recueillir des donnes statistiques et pour surveiller le rseau, et du push non sollicit, pour envoyer les notifications. Ce modle conceptuel souffre de plusieurs carences, notamment en ce qui concerne le t...

  10. Cloning and functional characterization of the SUR2/SYR2 gene encoding sphinganine hydroxylase in Pichia ciferrii.

    Science.gov (United States)

    Bae, Jung-Hoon; Sohn, Jung-Hoon; Park, Chang-Seo; Rhee, Joon-Shick; Choi, Eui-Sung

    2004-04-15

    Saccharomyces cerevisiae sphinganine C4-hydroxylase encoded by the SUR2 gene catalyses the conversion of sphinganine to phytosphingosine. We isolated the SUR2 gene from Pichia ciferrii using nucleotide sequence homology to S. cerevisiae SUR2 to study hydroxylation of sphinganine in the sphingoid base overproducing yeast P. ciferrii. A positive clone was confirmed by nucleotide sequencing. A syringomycin-E resistance phenotype of a S. cerevisiae sur2-null mutant was complemented by expression of the cloned P. ciferrii SUR2 gene. Restoration of phytosphingosine production in the complemented strain was also confirmed, indicating that the cloned gene is a functional homologue of S. cerevisiae SUR2. .

  11. Neutrino Experiments at Reactors

    Science.gov (United States)

    Reines, F.; Gurr, H. S.; Jenkins, T. L.; Munsee, J. H.

    1968-09-09

    A description is given of the electron-antineutrino program using a large fission reactor. A search has been made for a neutral weak interaction via the reaction (electron antineutrino + d .> p + n + electron antineutrino), the reaction (electron antineutrino + d .> n + n + e{sup +}) has now been detected, and an effort is underway to observe the elastic scattering reaction (electron antineutrino + e{sup -} .> electron antineutrino + e{sup -}) as well as to measure more precisely the reaction (electron antineutrino + p .> n + e{sup+}). The upper limit on the elastic scattering reaction which we have obtained with our large composite NaI, plastic, liquid scintillation detector is now about 50 times the predicted value.

  12. Neutronic Reactor Shield

    Science.gov (United States)

    Fermi, Enrico; Zinn, Walter H.

    The argument of the present Patent is a radiation shield suitable for protection of personnel from both gamma rays and neutrons. Such a shield from dangerous radiations is achieved to the best by the combined action of a neutron slowing material (a moderator) and a neutron absorbing material. Hydrogen is particularly effective for this shield since it is a good absorber of slow neutrons and a good moderator of fast neutrons. The neutrons slowed down by hydrogen may, then, be absorbed by other materials such as boron, cadmium, gadolinium, samarium or steel. Steel is particularly convenient for the purpose, given its effectiveness in absorbing also the gamma rays from the reactor (both primary gamma rays and secondary ones produced by the moderation of neutrons). In particular, in the present Patent a shield is described, made of alternate layers of steel and Masonite (an hydrolized ligno-cellulose material). The object of the present Patent is not discussed in any other published paper.

  13. Licensed reactor nuclear safety criteria applicable to DOE reactors

    Energy Technology Data Exchange (ETDEWEB)

    1993-11-01

    This document is a compilation and source list of nuclear safety criteria that the Nuclear Regulatory Commission (NRC) applies to licensed reactors; it can be used by DOE and DOE contractors to identify NRC criteria to be evaluated for application to the DOE reactors under their cognizance. The criteria listed are those that are applied to the areas of nuclear safety addressed in the safety analysis report of a licensed reactor. They are derived from federal regulations, USNRC regulatory guides, Standard Review Plan (SRP) branch technical positions and appendices, and industry codes and standards.

  14. Croissance hétérogène de semi-conducteurs III-V sur silicium : vers l'optoélectronique sur silicium

    OpenAIRE

    Cornet, Charles; Létoublon, Antoine; Guo, Weiming; Bondi, Alexandre; Richard, Soline; Rohel, Tony; Chevalier, Nicolas; Dehaese, Olivier; Tavernier, Karine; Perrin, Mathieu,; Jancu, Jean-Marc; Durand, Olivier; Bertru, Nicolas; Even, Jacky; Loualiche, Slimane

    2010-01-01

    National audience; L’intérêt d’une croissance hétérogène cohérente et monolithique de semiconducteurs III-V sur substrat de silicium est exposée au regard des composants optoélectroniques visés. Les derniers développements sur la croissance cohérente de GaP sur silicium, et des possibles émetteurs optiques seront présentés.

  15. Reactor service life extension program

    Energy Technology Data Exchange (ETDEWEB)

    Caskey, G.R.; Sindelar, R.L.; Ondrejcin, R.S.; Baumann, E.W.

    1990-12-31

    A review of the Savannah River Site production reactor systems was initiated in 1980 and led to implementation of the Reactor Materials Program in 1984 to assess reactor safety and reactor service life. The program evaluated performance of the reactor tanks, primary coolant piping, and thermal shields, components of welded construction that were fabricated from Type 304 stainless steel. The structural integrity analysis of the primary coolant system has shown that the pressure boundary is not susceptible to gross rupture, including a double ended guillotine break or equivalent large area bank. Residual service life is potentially limited by two material degradation modes, irradiation damage and intergranular stress corrosion cracking. Analysis of the structural integrity of the tanks and piping has shown that continued safe operation of the reactors for several additional decades is not limited by the material performance of the primary coolant system. Although irradiation damage has not degraded material behavior to an unacceptable level, past experience has revealed serious difficulties with repair welding on irradiated stainless steel. Stress corrosion can be mitigated by newly identified limits on impurity concentrations in the coolant water and by stress mitigation of weld residual stresses. Work continues in several areas: the effects of helium on mechanical behavior of irradiated stainless steel; improved weld methods for piping and the reactor tanks; and a surveillance program to track irradiation effects on the tank walls.

  16. Reactor service life extension program

    Energy Technology Data Exchange (ETDEWEB)

    Caskey, G.R.; Sindelar, R.L.; Ondrejcin, R.S.; Baumann, E.W.

    1990-01-01

    A review of the Savannah River Site production reactor systems was initiated in 1980 and led to implementation of the Reactor Materials Program in 1984 to assess reactor safety and reactor service life. The program evaluated performance of the reactor tanks, primary coolant piping, and thermal shields, components of welded construction that were fabricated from Type 304 stainless steel. The structural integrity analysis of the primary coolant system has shown that the pressure boundary is not susceptible to gross rupture, including a double ended guillotine break or equivalent large area bank. Residual service life is potentially limited by two material degradation modes, irradiation damage and intergranular stress corrosion cracking. Analysis of the structural integrity of the tanks and piping has shown that continued safe operation of the reactors for several additional decades is not limited by the material performance of the primary coolant system. Although irradiation damage has not degraded material behavior to an unacceptable level, past experience has revealed serious difficulties with repair welding on irradiated stainless steel. Stress corrosion can be mitigated by newly identified limits on impurity concentrations in the coolant water and by stress mitigation of weld residual stresses. Work continues in several areas: the effects of helium on mechanical behavior of irradiated stainless steel; improved weld methods for piping and the reactor tanks; and a surveillance program to track irradiation effects on the tank walls.

  17. Assessment of torsatrons as reactors

    Energy Technology Data Exchange (ETDEWEB)

    Lyon, J.F. (Oak Ridge National Lab., TN (United States)); Painter, S.L. (Australian National Univ., Canberra, ACT (Australia))

    1992-12-01

    Stellarators have significant operational advantages over tokamaks as ignited steady-state reactors because stellarators have no dangerous disruptions and no need for continuous current drive or power recirculated to the plasma, both easing the first wall, blanket, and shield design; less severe constraints on the plasma parameters and profiles; and better access for maintenance. This study shows that a reactor based on the torsatron configuration (a stellarator variant) could also have up to double the mass utilization efficiency (MUE) and a significantly lower cost of electricity (COE) than a conventional tokamak reactor (ARIES-I) for a range of assumptions. Torsatron reactors can have much smaller coil systems than tokamak reactors because the coils are closer to the plasma and they have a smaller cross section (higher average current density because of the lower magnetic field). The reactor optimization approach and the costing and component models are those used in the current stage of the ARIES-I tokamak reactor study. Typical reactor parameters for a 1-GW(e) Compact Torsatron reactor example are major radius R[sub 0] = 6.6-8.8 m, on-axis magnetic field B[sup 0] = 4.8-7.5 T, B[sub max] (on coils) = 16 T, MUE 140-210 kW(e)/tonne, and COE (in constant 1990 dollars) = 67-79 mill/kW(e)h. The results are relatively sensitive to assumptions on the level of confinement improvement and the blanket thickness under the inboard half of the helical windings but relatively insensitive to other assumptions.

  18. Actualités sur la vitamine D*

    Directory of Open Access Journals (Sweden)

    Souberbielle Jean-Claude

    2014-05-01

    Full Text Available Le déficit et l’insuffisance en vitamine D, définis respectivement par des concentrations sériques de 25 hydroxyvitamine D (25OHD inférieures à 20 ng/ml et entre 20 et 30 ng/ml, sont des situations très fréquentes qui sont associées à une augmentation du risque de développer différentes pathologies, pas seulement osseuses. Les effets d’une supplémentation en vitamine D sur la diminution du risque de fractures et de chutes sont documentés par différentes études d’intervention. Les autres effets potentiels extra-osseux de la vitamine D sont principalement documentés par des études observationnelles et expérimentales. Même s’il n’existe pas encore de consensus sur les besoins en vitamine D, tous les experts s’accordent pour considérer que les AJR (200 UI/J en France sont très insuffisants et doivent être augmentés. Cet article aborde successivement le métabolisme de la vitamine D et ses effets, la définition du statut vitaminique D basée sur la concentration sérique de 25OHD, les indications du dosage de la 25OHD (qui ne doit pas être prescrit à tout le monde et propose des modalités de traitement.

  19. Le livre sur le livre traité de documentation

    CERN Document Server

    Otlet, Paul

    2015-01-01

    Paul Otlet est considéré comme le père des sciences de l'information. Ouvrage fondateur et fondamental, le Traité de documentation. Le livre sur le livre (1934) est l'aboutissement de son travail inlassable pour rassembler, classer et partager les connaissances. Otlet y propose une remarquable synthèse du savoir sur le livre et le document en même temps qu'il anticipe Internet et l'hypertexte. La réédition du Traité de documentation, 70 ans après la disparition de son auteur, coïncide avec la réouverture du Mundaneum à Mons, où le fabuleux héritage documentaire légué par Paul Otlet et Henri La Fontaine est conservé. « Ici, la table de travail n'est plus chargée d'aucun livre. À leur place se dresse un écran et à portée un téléphone. Là-bas, au loin, dans un édifice immense, sont tous les livres et tous les renseignements. De là, on fait apparaître sur l'écran la page à lire pour connaître la réponse aux questions posées par téléphone. » Préfaces de Benoît Peeters (éc...

  20. Candida albicans SUR7 contributes to secretion, biofilm formation, and macrophage killing

    Directory of Open Access Journals (Sweden)

    Bernardo Stella M

    2010-04-01

    Full Text Available Abstract Background Candida albicans SUR7 has been shown to be required for plasma membrane organization and cell wall synthesis, but its role in virulence is not known. Using a bioinformatics strategy, we previously identified several novel putative secretion pathway proteins potentially involved in virulence, including the C. albicans homolog of the Saccharomyces cerevisiae endocytosis-related protein Sur7p. We therefore generated a C. albicans sur7Δ null mutant and examined its contribution to key virulence attributes. Results Structurally, the C. albicans sur7Δ mutant was impaired in response to filamentation-inducing conditions, and formed aberrant hyphae with extensive accumulation of plasma membrane-derived structures within the cell. Absence of SUR7 resulted in a temperature-sensitive growth defect at high temperatures (42°C, which was partially rescued by addition of NaCl. We next examined the role of the SUR7 paralog C. albicans FMP45 in this temperature-sensitive phenotype. Analysis of C. albicans Fmp45p-GFP demonstrated co-localization of Fmp45p with Sur7p and increased fluorescence in the plasma membrane in the presence of high salt. We next focused on key virulence-related phenotypes. The C. albicans sur7Δ null mutant exhibited secretory defects: reduced lipase secretion, and increased levels of secreted Sap2p. The null mutant was hyper-susceptible to sub-inhibitory concentrations of caspofungin, but not amphotericin B and 5-fluorocytosine. Functionally, the sur7Δ mutant demonstrated increased adhesion to polystyrene and of note, was markedly defective in biofilm formation. In an in vitro macrophage model of virulence, the sur7Δ mutant was impaired in macrophage killing. Conclusions Plasma membrane and cell wall organization are important for cell morphology, and alterations of these structures contributed to impairment of several key virulence-associated phenotypes in the C. albicans sur7Δ mutant.

  1. Concept for LEU Burst Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Klein, Steven Karl [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Kimpland, Robert Herbert [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-03-07

    Design and performance of a proposed LEU burst reactor are sketched. Salient conclusions reached are the following: size would be ~1,500 kg or greater, depending on the size of the central cavity; internal stresses during burst require split rings for relief; the reactor would likely require multiple control and safety rods for fine control; the energy spectrum would be comparable to that of HEU machines; and burst yields and steady-state power levels will be significantly greater in an LEU reactor.

  2. Nuclear reactor downcomer flow deflector

    Energy Technology Data Exchange (ETDEWEB)

    Gilmore, Charles B. (Greensburg, PA); Altman, David A. (Pittsburgh, PA); Singleton, Norman R. (Murrysville, PA)

    2011-02-15

    A nuclear reactor having a coolant flow deflector secured to a reactor core barrel in line with a coolant inlet nozzle. The flow deflector redirects incoming coolant down an annulus between the core barrel and the reactor vessel. The deflector has a main body with a front side facing the fluid inlet nozzle and a rear side facing the core barrel. The rear side of the main body has at least one protrusion secured to the core barrel so that a gap exists between the rear side of the main body adjacent the protrusion and the core barrel. Preferably, the protrusion is a relief that circumscribes the rear side of the main body.

  3. Safety of VVER-440 reactors

    CERN Document Server

    Slugen, Vladimir

    2011-01-01

    Safety of VVER-440 Reactors endeavours to promote an increase in the safety of VVER-440 nuclear reactors via the improvement of fission products limitation systems and the implementation of special non-destructive spectroscopic methods for materials testing. All theoretical and experimental studies performed the by author over the last 25 years have been undertaken with the aim of improving VVER-440 defence in depth, which is one of the most important principle for ensuring safety in nuclear power plants. Safety of VVER-440 Reactors is focused on the barrier system through which the safety pri

  4. Random processes in nuclear reactors

    CERN Document Server

    Williams, M M R

    1974-01-01

    Random Processes in Nuclear Reactors describes the problems that a nuclear engineer may meet which involve random fluctuations and sets out in detail how they may be interpreted in terms of various models of the reactor system. Chapters set out to discuss topics on the origins of random processes and sources; the general technique to zero-power problems and bring out the basic effect of fission, and fluctuations in the lifetime of neutrons, on the measured response; the interpretation of power reactor noise; and associated problems connected with mechanical, hydraulic and thermal noise sources

  5. Fuel Fabrication and Nuclear Reactors

    Energy Technology Data Exchange (ETDEWEB)

    Karpius, Peter Joseph [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2017-02-02

    The uranium from the enrichment plant is still in the form of UF6. UF6 is not suitable for use in a reactor due to its highly corrosive chemistry as well as its phase diagram. UF6 is converted into UO2 fuel pellets, which are in turn placed in fuel rods and assemblies. Reactor designs are variable in moderators, coolants, fuel, performance etc.The dream of energy ‘too-cheap to meter’ is no more, and now the nuclear power industry is pushing ahead with advanced reactor designs.

  6. La desceme des oies sauvages sur le sable

    Institute of Scientific and Technical Information of China (English)

    李金佳

    1999-01-01

    北京外国语大学96届硕士研究生李金佳在法国攻读博士学位期间,用法语创作的小说“La descente des oies sauvages sur le sable”荣获法国1999年度“法语青年作家奖。”本刊将分两期刊登该小说全文,以飨读者。

  7. Pensando en el sur. El Llano en el siglo XVII

    OpenAIRE

    1994-01-01

    Not available.

    La agresión occidental a la futura Venezuela supuso, entre otras muchas cosas, que quienes la rechazaron, africanos que no querían ser esclavos, nativos huyendo del acoso o blancos refractarios, organizaran una sociedad cimarrona en el Llano. Cuadrúpedos huidos también del norte incrementaron la oferta de herbívoros cazables e implicaron, con los equinos, mayor autonomía y capacidad defensiva. También pensaron en el sur, por motivos antagónicos, quienes ...

  8. Retour sur l’épidémiologie populaire

    OpenAIRE

    Brown, Phil

    2013-01-01

    Dans un article de 1987, j’ai forgé l’expression d’« épidémiologie populaire » pour décrire les pratiques de signalement, d’analyse scientifique et de mobilisation politique des populations vivant sur des sites contaminés par des déchets toxiques (Brown, 1987). Depuis lors, j’ai développé ce concept dans plusieurs articles (Brown, 1992 ; Brown & Masterson-Allen, 1994 ; Brown & Ferguson, 1995), dans un livre (Brown & Mikkelsen, 1990), et de nombreux chercheurs l’ont jugé suffisamment utile pou...

  9. Moteur à énergie solaire sur paliers supraconducteurs

    OpenAIRE

    Berger, Kévin; Boufatah, Fawzi; Menana, Hocine; Hinaje, Melika; Douine, Bruno; Lévêque, Jean

    2016-01-01

    Oral; National audience; Cet article présente l’étude de conception et de réalisation d’une structure originale de moteur électrique à énergie solaire, lévitant sur des paliers supraconducteurs. Le principe de fonctionnement et la structure sont d’abord exposés. Puis, un modèle électrique de la machine est obtenu à travers la modélisation analytique des grandeurs électromagnétiques. Nous précisons ensuite quelques éléments concernant la réalisation, en particulier, les paliers supraconducteur...

  10. La grande vitesse est-elle toujours sur les rails ?

    OpenAIRE

    Libourel, Eloïse; Ruggeri, Charlotte; Schorung, Matthieu

    2016-01-01

    National audience; Depuis le milieu du XXème, la grande vitesse ferroviaire est considérée comme une innovation révolutionnaire pour le transport de voyageurs. Elle renvoie une image de modernité à tous les acteurs institutionnels et à la société civile, et elle permet également aux États d’afficher une image de puissance technique et industrielle. L’objectif est de capitaliser sur l’objet « grande vitesse » pour valoriser l’avancée technologique d’un pays, d’une région, et pour promouvoir de...

  11. Zoom on India | Gros plan sur l’Inde

    Directory of Open Access Journals (Sweden)

    2012-05-01

    Full Text Available Indian Energy Production and Consumption (in Million Tonnes of Oil EquivalentProduction et consommation d’énergie en Inde (en millions de tonnes d’équivalent pétroleSource: World Bank, World Bank Development Indicators, 2010.Indian Oil, Gas and Coal Imports (in Million Tonnes of Oil Equivalent, 2008*Importations indiennes de pétrole, de gaz et de charbon (en millions de tonnes d’équivalent pétrole, 2008** 2009 for coal data | 2009 pour les données sur le charbon.Sources: British Petroleum...

  12. Nuclear reactor PBMR and cogeneration; Reactor nuclear PBMR y cogeneracion

    Energy Technology Data Exchange (ETDEWEB)

    Ramirez S, J. R.; Alonso V, G., E-mail: ramon.ramirez@inin.gob.mx [ININ, Carretera Mexico-Toluca s/n, 52750 Ocoyoacac, Estado de Mexico (Mexico)

    2013-10-15

    In recent years the nuclear reactor designs for the electricity generation have increased their costs, so that at the moment costs are managed of around the 5000 US D for installed kw, reason for which a big nuclear plant requires of investments of the order of billions of dollars, the designed reactors as modular of low power seek to lighten the initial investment of a big reactor dividing the power in parts and dividing in modules the components to lower the production costs, this way it can begin to build a module and finished this to build other, differing the long term investment, getting less risk therefore in the investment. On the other hand the reactors of low power can be very useful in regions where is difficult to have access to the electric net being able to take advantage of the thermal energy of the reactor to feed other processes like the water desalination or the vapor generation for the processes industry like the petrochemical, or even more the possible hydrogen production to be used as fuel. In this work the possibility to generate vapor of high quality for the petrochemical industry is described using a spheres bed reactor of high temperature. (Author)

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

    Energy Technology Data Exchange (ETDEWEB)

    Jacquet, P.

    2011-05-23

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

  14. FASTER test reactor preconceptual design report summary

    Energy Technology Data Exchange (ETDEWEB)

    Grandy, C. [Argonne National Lab. (ANL), Argonne, IL (United States); Belch, H. [Argonne National Lab. (ANL), Argonne, IL (United States); Brunett, A. [Argonne National Lab. (ANL), Argonne, IL (United States); Heidet, F. [Argonne National Lab. (ANL), Argonne, IL (United States); Hill, R. [Argonne National Lab. (ANL), Argonne, IL (United States); Hoffman, E. [Argonne National Lab. (ANL), Argonne, IL (United States); Jin, E. [Argonne National Lab. (ANL), Argonne, IL (United States); Mohamed, W. [Argonne National Lab. (ANL), Argonne, IL (United States); Moisseytsev, A. [Argonne National Lab. (ANL), Argonne, IL (United States); Passerini, S. [Argonne National Lab. (ANL), Argonne, IL (United States); Sienicki, J. [Argonne National Lab. (ANL), Argonne, IL (United States); Sumner, T. [Argonne National Lab. (ANL), Argonne, IL (United States); Vilim, R. [Argonne National Lab. (ANL), Argonne, IL (United States); Hayes, Steven [Argonne National Lab. (ANL), Argonne, IL (United States)

    2016-02-29

    The FASTER reactor plant is a sodium-cooled fast spectrum test reactor that provides high levels of fast and thermal neutron flux for scientific research and development. The 120MWe FASTER reactor plant has a superheated steam power conversion system which provides electrical power to a local grid allowing for recovery of operating costs for the reactor plant.

  15. ADAPTIVE CONTROL SYSTEM OF INDUSTRIAL REACTORS

    Directory of Open Access Journals (Sweden)

    Vyacheslav K. Mayevski

    2014-01-01

    Full Text Available This paper describes a mathematical model of an industrial chemical reactor for production of synthetic rubber. During reactor operation the model parameters vary considerably. To create a control algorithm performed transformation of mathematical model of the reactor in order to obtain a dependency that can be used to determine the model parameters are changing during reactor operation.

  16. FASTER Test Reactor Preconceptual Design Report

    Energy Technology Data Exchange (ETDEWEB)

    Grandy, C. [Argonne National Lab. (ANL), Argonne, IL (United States); Belch, H. [Argonne National Lab. (ANL), Argonne, IL (United States); Brunett, A. J. [Argonne National Lab. (ANL), Argonne, IL (United States); Heidet, F. [Argonne National Lab. (ANL), Argonne, IL (United States); Hill, R. [Argonne National Lab. (ANL), Argonne, IL (United States); Hoffman, E. [Argonne National Lab. (ANL), Argonne, IL (United States); Jin, E. [Argonne National Lab. (ANL), Argonne, IL (United States); Mohamed, W. [Argonne National Lab. (ANL), Argonne, IL (United States); Moisseytsev, A. [Argonne National Lab. (ANL), Argonne, IL (United States); Passerini, S. [Argonne National Lab. (ANL), Argonne, IL (United States); Sienicki, J. [Argonne National Lab. (ANL), Argonne, IL (United States); Sumner, T. [Argonne National Lab. (ANL), Argonne, IL (United States); Vilim, R. [Argonne National Lab. (ANL), Argonne, IL (United States); Hayes, S. [Argonne National Lab. (ANL), Argonne, IL (United States)

    2016-03-31

    The FASTER test reactor plant is a sodium-cooled fast spectrum test reactor that provides high levels of fast and thermal neutron flux for scientific research and development. The 120MWe FASTER reactor plant has a superheated steam power conversion system which provides electrical power to a local grid allowing for recovery of operating costs for the reactor plant.

  17. Breeder Reactors, Understanding the Atom Series.

    Science.gov (United States)

    Mitchell, Walter, III; Turner, Stanley E.

    The theory of breeder reactors in relationship to a discussion of fission is presented. Different kinds of reactors are characterized by the cooling fluids used, such as liquid metal, gas, and molten salt. The historical development of breeder reactors over the past twenty-five years includes specific examples of reactors. The location and a brief…

  18. Evolution of the tandem mirror reactor concept

    Energy Technology Data Exchange (ETDEWEB)

    Carlson, G.A.; Logan, B.G.

    1982-03-09

    We discuss the evolution of the tandem mirror reactor concept from the original conceptual reactor design (1977) through the first application of the thermal barrier concept to a reactor design (1979) to the beginning of the Mirror Advanced Reactor Study (1982).

  19. La Cooperación Sur-Sur y Triangular: ¿subversión o adaptación de la cooperación internacional? . Bruno Ayllon

    OpenAIRE

    2014-01-01

    Book review "La Cooperación Sur-Sur y Triangular: ¿subversión o adaptación de la cooperación internacional?" by Bruno Ayllon Reseña del libro "La Cooperación Sur-Sur y Triangular: ¿subversión o adaptación de la cooperación internacional?" escrito por Bruno Ayllon

  20. Jules Horowitz Reactor, basic design

    Energy Technology Data Exchange (ETDEWEB)

    Bergamaschi, Y.; Bouilloux, Y.; Chantoin, P.; Guigon, B.; Bravo, X.; Germain, C.; Rommens, M.; Tremodeux, P

    2003-07-01

    Since the shutdown of the SILOE reactor in 1997, the OSIRIS reactor has ensured the needs regarding technological irradiation at CEA including those of its industrial partners and customers. The Jules Horowitz Reactor will replace it. It has the ambition to provide the necessary nuclear data and maintain a fission research capacity in Europe after 2010. This capacity should be service-oriented. It will be established in Cadarache. The Jules Horowitz reactor will also: - represent a significant step in term of performances and experimental capabilities, - be designed with a high flexibility, in order to satisfy the current demand from European industry, research and be able to accommodate future requirements, - reach a high level of safety, according to the best current practice. This paper will present the main functionalities and the design options resulting from the 'preliminary design' studies. (authors)

  1. Advanced Catalytic Hydrogenation Retrofit Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Reinaldo M. Machado

    2002-08-15

    Industrial hydrogenation is often performed using a slurry catalyst in large stirred-tank reactors. These systems are inherently problematic in a number of areas, including industrial hygiene, process safety, environmental contamination, waste production, process operability and productivity. This program proposed the development of a practical replacement for the slurry catalysts using a novel fixed-bed monolith catalyst reactor, which could be retrofitted onto an existing stirred-tank reactor and would mitigate many of the minitations and problems associated with slurry catalysts. The full retrofit monolith system, consisting of a recirculation pump, gas/liquid ejector and monolith catalyst, is described as a monolith loop reactor or MLR. The MLR technology can reduce waste and increase raw material efficiency, which reduces the overall energy required to produce specialty and fine chemicals.

  2. Advanced Carbothermal Electric Reactor Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The overall objective of the Phase 1 effort was to demonstrate the technical feasibility of the Advanced Carbothermal Electric (ACE) Reactor concept. Unlike...

  3. Reactor operation environmental information document

    Energy Technology Data Exchange (ETDEWEB)

    Bauer, L.R.; Hayes, D.W.; Hunter, C.H.; Marter, W.L.; Moyer, R.A.

    1989-12-01

    This volume is a reactor operation environmental information document for the Savannah River Plant. Topics include meteorology, surface hydrology, transport, environmental impacts, and radiation effects. 48 figs., 56 tabs. (KD)

  4. Unique features of space reactors

    Science.gov (United States)

    Buden, David

    Space reactors are designed to meet a unique set of requirements; they must be sufficiently compact to be launched in a rocket to their operational location, operate for many years without maintenance and servicing, operate in extreme environments, and reject heat by radiation to space. To meet these restrictions, operating temperatures are much greater than in terrestrial power plants, and the reactors tend to have a fast neutron spectrum. Currently, a new generation of space reactor power plants is being developed. The major effort is in the SP-100 program, where the power plant is being designed for seven years of full power, and no maintenance operation at a reactor outlet operating temperature of 1350 K.

  5. Thermal Analysis for Mobile Reactor

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    <正>Mobile reactor design in the paper is consisted of two grades of thermal electric conversion. The first grade is the thermionic conversion inside the core and the second grade is thermocouple conversion

  6. Teaching About Nature's Nuclear Reactors

    CERN Document Server

    Herndon, J M

    2005-01-01

    Naturally occurring nuclear reactors existed in uranium deposits on Earth long before Enrico Fermi built the first man-made nuclear reactor beneath Staggs Field in 1942. In the story of their discovery, there are important lessons to be learned about scientific inquiry and scientific discovery. Now, there is evidence to suggest that the Earth's magnetic field and Jupiter's atmospheric turbulence are driven by planetary-scale nuclear reactors. The subject of planetocentric nuclear fission reactors can be a jumping off point for stimulating classroom discussions about the nature and implications of planetary energy sources and about the geomagnetic field. But more importantly, the subject can help to bring into focus the importance of discussing, debating, and challenging current thinking in a variety of areas.

  7. Advanced Carbothermal Electric Reactor Project

    Data.gov (United States)

    National Aeronautics and Space Administration — ORBITEC proposes to develop the Advanced Carbothermal Electric (ACE) reactor to efficiently extract oxygen from lunar regolith. Unlike state-of-the-art carbothermal...

  8. Test du Module BECKHOFF (BK7420) Entrées/Sorties deportees sur FIPIO de SCHNEIDER

    CERN Document Server

    Palluel, J; CERN. Geneva. AB Department

    2004-01-01

    Cette note présente le test du nouveau coupleur I/O déporté sur FIPIO de Beckhoff référencé BK7420 (voir photo ci-dessous), et notamment son évaluation sur différentes longueurs par rapport à un module semblable de Schneider (Momentum 170 FNT 110 01).

  9. 46 CFR 7.130 - Point Conception, CA to Point Sur, CA.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 1 2010-10-01 2010-10-01 false Point Conception, CA to Point Sur, CA. 7.130 Section 7.130 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY PROCEDURES APPLICABLE TO THE PUBLIC BOUNDARY LINES Pacific Coast § 7.130 Point Conception, CA to Point Sur, CA. (a) A line drawn from...

  10. Solid State Reactor Final Report

    Energy Technology Data Exchange (ETDEWEB)

    Mays, G.T.

    2004-03-10

    The Solid State Reactor (SSR) is an advanced reactor concept designed to take advantage of Oak Ridge National Laboratory's (ORNL's) recently developed graphite foam that has enhanced heat transfer characteristics and excellent high-temperature mechanical properties, to provide an inherently safe, self-regulated, source of heat for power and other potential applications. This work was funded by the U.S. Department of Energy's Nuclear Energy Research Initiative (NERI) program (Project No. 99-064) from August 1999 through September 30, 2002. The initial concept of utilizing the graphite foam as a basis for developing an advanced reactor concept envisioned that a suite of reactor configurations and power levels could be developed for several different applications. The initial focus was looking at the reactor as a heat source that was scalable, independent of any heat removal/power conversion process. These applications might include conventional power generation, isotope production and destruction (actinides), and hydrogen production. Having conducted the initial research on the graphite foam and having performed the scoping parametric analyses from neutronics and thermal-hydraulic perspectives, it was necessary to focus on a particular application that would (1) demonstrate the viability of the overall concept and (2) require a reasonably structured design analysis process that would synthesize those important parameters that influence the concept the most as part of a feasible, working reactor system. Thus, the application targeted for this concept was supplying power for remote/harsh environments and a design that was easily deployable, simplistic from an operational standpoint, and utilized the new graphite foam. Specifically, a 500-kW(t) reactor concept was pursued that is naturally load following, inherently safe, optimized via neutronic studies to achieve near-zero reactivity change with burnup, and proliferation resistant. These four major areas

  11. Microchannel Reactors for ISRU Applications

    Science.gov (United States)

    Carranza, Susana; Makel, Darby B.; Blizman, Brandon; Ward, Benjamin J.

    2005-02-01

    Affordable planning and execution of prolonged manned space missions depend upon the utilization of local resources and the waste products which are formed in manned spacecraft and surface bases. Successful in-situ resources utilization (ISRU) will require component technologies which provide optimal size, weight, volume, and power efficiency. Microchannel reactors enable the efficient chemical processing of in situ resources. The reactors can be designed for the processes that generate the most benefit for each mission. For instance, propellants (methane) can be produced from carbon dioxide from the Mars atmosphere using the Sabatier reaction and ethylene can be produced from the partial oxidation of methane. A system that synthesizes ethylene could be the precursor for systems to synthesize ethanol and polyethylene. Ethanol can be used as a nutrient for Astrobiology experiments, as well as the production of nutrients for human crew (e.g. sugars). Polyethylene can be used in the construction of habitats, tools, and replacement parts. This paper will present recent developments in miniature chemical reactors using advanced Micro Electro Mechanical Systems (MEMS) and microchannel technology to support ISRU of Mars and lunar missions. Among other applications, the technology has been demonstrated for the Sabatier process and for the partial oxidation of methane. Microchannel reactors were developed based on ceramic substrates as well as metal substrates. In both types of reactors, multiple layers coated with catalytic material are bonded, forming a monolithic structure. Such reactors are readily scalable with the incorporation of extra layers. In addition, this reactor structure minimizes pressure drop and catalyst settling, which are common problems in conventional packed bed reactors.

  12. Reactor antineutrinos and nuclear physics

    Science.gov (United States)

    Balantekin, A. B.

    2016-11-01

    Short-baseline reactor neutrino experiments successfully measured the neutrino parameters they set out to measure, but they also identified a shape distortion in the 5-7 MeV range as well as a reduction from the predicted value of the flux. Nuclear physics input into the calculations of reactor antineutrino spectra needs to be better refined if this anomaly is to be interpreted as due to sterile neutrino states.

  13. Reactor Simulator Testing

    Science.gov (United States)

    Schoenfeld, Michael P.; Webster, Kenny L.; Pearson, Boise J.

    2013-01-01

    As part of the Nuclear Systems Office Fission Surface Power Technology Demonstration Unit (TDU) project, a reactor simulator test loop (RxSim) was design & built to perform integrated testing of the TDU components. In particular, the objectives of RxSim testing was to verify the operation of the core simulator, the instrumentation and control system, and the ground support gas and vacuum test equipment. In addition, it was decided to include a thermal test of a cold trap purification design and a pump performance test at pump voltages up to 150 V since the targeted mass flow rate of 1.75 kg/s was not obtained in the RxSim at the originally constrained voltage of 120 V. This paper summarizes RxSim testing. The gas and vacuum ground support test equipment performed effectively in NaK fill, loop pressurization, and NaK drain operations. The instrumentation and control system effectively controlled loop temperature and flow rates or pump voltage to targeted settings. The cold trap design was able to obtain the targeted cold temperature of 480 K. An outlet temperature of 636 K was obtained which was lower than the predicted 750 K but 156 K higher than the cold temperature indicating the design provided some heat regeneration. The annular linear induction pump (ALIP) tested was able to produce a maximum flow rate of 1.53 kg/s at 800 K when operated at 150 V and 53 Hz.

  14. Novel Catalytic Membrane Reactors

    Energy Technology Data Exchange (ETDEWEB)

    Stuart Nemser, PhD

    2010-10-01

    There are many industrial catalytic organic reversible reactions with amines or alcohols that have water as one of the products. Many of these reactions are homogeneously catalyzed. In all cases removal of water facilitates the reaction and produces more of the desired chemical product. By shifting the reaction to right we produce more chemical product with little or no additional capital investment. Many of these reactions can also relate to bioprocesses. Given the large number of water-organic compound separations achievable and the ability of the Compact Membrane Systems, Inc. (CMS) perfluoro membranes to withstand these harsh operating conditions, this is an ideal demonstration system for the water-of-reaction removal using a membrane reactor. Enhanced reaction synthesis is consistent with the DOE objective to lower the energy intensity of U.S. industry 25% by 2017 in accord with the Energy Policy Act of 2005 and to improve the United States manufacturing competitiveness. The objective of this program is to develop the platform technology for enhancing homogeneous catalytic chemical syntheses.

  15. LMFBR type reactor

    Energy Technology Data Exchange (ETDEWEB)

    Iwashige, Kengo

    1996-06-21

    In an LMFBR type reactor, partitions are disposed to a coolant channel at positions lower than the free liquid level, and the width of the partitions is adapted to have a predetermined condition. Namely, when low temperature fluid overflowing the wall of the coolant channel, flows down and collided against the free liquid surface in the coolant channel, since the dropping speed thereof is reduced abruptly, large pressure waves are caused by kinetic force of the low temperature fluid. However, if appropriate numbers of partitions having an appropriate shape are formed, the dropping speed of the low temperature fluid is moderated to reduce the pressure waves. In addition, since the pressure waves are dispersed to the circumferential and lateral directions of the coolant flow channel respectively, the propagation of the pressure waves can be prevented effectively. Further, when the flow of the low temperature fluid is changed to the circumferential direction, for example, by earthquakes, since the partitions act as members resisting against the circumferential change of the low temperature fluid, the change of the direction can be suppressed. (N.H.)

  16. Perfil del profesor nativo de ELE en Corea del Sur

    Directory of Open Access Journals (Sweden)

    Miró Martí, Oriol

    2015-04-01

    Full Text Available La presencia de profesorado universitario nativo de ELE en Corea del Sur está aumentando en la actualidad, aunque todavía no deje de ser un hecho meramente anecdótico respecto a la presencia de profesorado nativo de otras lenguas como el inglés o el chino. Todo ello responde a una realidad ligada al aumento de estudiantes universitarios que eligen como lengua de estudio el español y a la necesidad creciente de ofrecerles las herramientas suficientes para defenderse en esta lengua. Pero, ¿por qué se contrata a personal nativo para la enseñanza de español en Corea del Sur? ¿Cuál es su rol en la universidad? ¿Cómo y dónde encaja el docente nativo en este escenario educativo? Y, por último, ¿cumple las expectativas que de él se espera? Con este artículo, que es fruto de una ampliación del trabajo de final de Máster de uno de sus autores, hemos trazado el perfil prototípico del docente de español en el sistema universitario surcoreano.

  17. Notes sur le Paléolithique du Maroc Meridional

    Directory of Open Access Journals (Sweden)

    Pierre BIBERSON

    2009-10-01

    Full Text Available Le Vº Congrés Panafricain de Préhistoire et de l'Etude du Quaternaire qui s'est tenu a Santa Cruz de Tenerife en 1963 a mis en lumiére l'importanee de la región du Sud-marocain qui, sur le continent, fait face à l'archipel des lies Canaries. A l'heure actuelle, sauf sur une tres étroite bande littorale, c'est une región purement désertique; mais elle a livré des vestiges préhistoriques de diverses époques du Quaternaire qui montrent que, a certains moments, elle a été largement fréquentée par les hommes du Paléolithique, puis du Néolithique, ce qui implique des périodes aux conditions climatiques tres différentes de celles de l'époque présente.

  18. DECISIONS ET COMPETITIVITE SUR LE MARCHE UNIQUE EUROPEEN

    Directory of Open Access Journals (Sweden)

    Sirghi Nicoleta

    2008-05-01

    Full Text Available L’un des traits importants du marché unique européen, a comme source le męme énoncé du principal objectif de l’intégration européenne ainsi que: l’harmonisation des niveaux du développement des Etats Membres et l’augmentation du niveau de vie dans l’ensemble de la communauté. Pour le marché unique européen, cet aspect se traduit par une permanente et soutenue augmentation de la demande. Cet ouvrage présente au début une analyse des éléments spécifiques du marché européen. Ensuite on identifie les opportunités et les risques au niveau macroéconomique adjointes aux perspectives du marché unique européen. Comme fondement on présente des stratégies du développement réalisables au niveau microéconomique que puissent assurer l’augmentation du niveau sur la compétitivité des sociétés sur le marché unique européen.

  19. Entretien sur la psychanalyse: réflexions en marge

    Directory of Open Access Journals (Sweden)

    Giuseppe Martini

    2016-08-01

    Full Text Available L’auteur propose ici un commentaire sur les points les plus importants de son entretien de février 2003 avec Paul Ricœur consacré aux rapports entre herméneutique et psychanalyse. Bien que le philosophe se situe dans une réelle continuité par rapport à sa contribution de 1965, il enrichit toutefois sa réflexion philosophique sur la psychanalyse en proposant plusieurs innovations, en ce qui concerne plus particulièrement les thèmes du récit, du soi et de l’éthique. Dans les conclusions de son commentaire, l’auteur souligne l’importance des concepts d’“irreprésentable” et d’“intraduisible”: non seulement, en effet, ces concepts sont dans la ligne de nombreuses contributions de la psychanalyse contemporaine, mais la profondeur de la réflexion ricœurienne augmente en outre leur potentiel théorique et même clinique.

  20. Calculation of reactor antineutrino spectra in TEXONO

    CERN Document Server

    Chen Dong Liang; Mao Ze Pu; Wong, T H

    2002-01-01

    In the low energy reactor antineutrino physics experiments, either for the researches of antineutrino oscillation and antineutrino reactions, or for the measurement of abnormal magnetic moment of antineutrino, the flux and the spectra of reactor antineutrino must be described accurately. The method of calculation of reactor antineutrino spectra was discussed in detail. Furthermore, based on the actual circumstances of NP2 reactors and the arrangement of detectors, the flux and the spectra of reactor antineutrino in TEXONO were worked out

  1. Tritium management in fusion reactors

    Energy Technology Data Exchange (ETDEWEB)

    Galloway, T.R.

    1978-05-01

    This is a review paper covering the key environmental and safety issues and how they have been handled in the various magnetic and inertial confinement concepts and reference designs. The issues treated include: tritium accident analyses, tritium process control, occupational safety, HTO formation rate from the gas-phase, disposal of tritium contaminated wastes, and environmental impact--each covering the Joint European Tokamak (J.E.T. experiment), Tokamak Fusion Test Reactor (TFTR), Russian T-20, The Next Step (TNS) designs by Westinghouse/ORNL and General Atomic/ANL, the ANL and ORNL EPR's, the G.A. Doublet Demonstration Reactor, the Italian Fintor-D and the ORNL Demo Studies. There are also the following full scale plant reference designs: UWMAK-III, LASL's Theta Pinch Reactor Design (RTPR), Mirror Fusion Reactor (MFR), Tandem Mirror Reactor (TMR), and the Mirror Hybrid Reactor (MHR). There are four laser device breakeven experiments, SHIVA-NOVA, LLL reference designs, ORNL Laser Fusion power plant, the German ''Saturn,'' and LLL's Laser Fusion EPR I and II.

  2. Sur la plurifonctionnalité du discours direct

    Directory of Open Access Journals (Sweden)

    Cigada Sara

    2012-07-01

    Full Text Available La comparaison entre les résultats de nombreux travaux sur le dialogue dans le texte littéraire, sur l’attestation linguistique de la subjectivité, sur la fonction argumentative des émotions dans le discours et sur les effets de polyphonie, suggère que la structure sémiotique et linguistique du discours direct (DD se trouve au croisement stratégique de plusieurs axes de la construction discursive. Nous étudions donc l’insertion du DD dans le discours (cf. Rosier 2008: Le discours rapporté en français; Kerbrat 2005: Le Discours en interaction et Id. 2008: Le Dialogue comme objet d’analyse linguistique; Maingueneau 2010: Manuel de linguistique pour le texte littéraire en tant que phénomène de rupture sémiotique (Genette 1972: Figures III et Id. 1983: Nouveau discours du récit, dans ses fonctions discursives plurielles, tantôt émotives (Tannen 1989: Talking Voices; Plantin-Traverso-Vosghanian 2008: Parcours des émotions en interaction, tantôt argumentatives (Doury 2001: La Fonction argumentative des échanges rapportés; Stati 1990: Le transphrastique. Du point de vue méthodologique, nous nous proposons de revisiter empiriquement, par l'étude de corpus, les traits linguistiques structuraux qui caractérisent l’insertion du DD dans un récit à l'écrit, en les comparant systématiquement aux traits de l’insertion du DD dans un récit à l'oral. Une analyse parallèle est possible en ce qui concerne les fonctions discursives, que le DD typiquement déroule dans les récits. Les fonctions du DD décrites à partir de l'étude des corpus sont plurielles: on reconnaît des fonctions fortement argumentatives d'autres plus typiquement narratives, tandis que d'autres encore amalgament les deux fonctions. Le « contrat de littéralité », qui selon Genette ne porterait jamais que sur la teneur du discours, doit donc être fortement nuancé selon les contextes, tandis que l'effet de sens le plus directement lié à la

  3. Transgenic overexpression of SUR1 in the heart suppresses sarcolemmal K(ATP).

    Science.gov (United States)

    Flagg, Thomas P; Remedi, Maria Sara; Masia, Ricard; Gomes, Jefferson; McLerie, Meredith; Lopatin, Anatoli N; Nichols, Colin G

    2005-10-01

    The lack of pathological consequences of cardiac ATP-sensitive potassium channel (K(ATP)) channel gene manipulation is in stark contrast to the effect of similar perturbations in the pancreatic beta-cell. Because the pancreatic and cardiac channel share the same pore-forming subunit (Kir6.2), the different effects of genetic manipulation likely reflect, at least in part, the tissue-specific expression of the regulatory subunit (SUR1 in pancreas vs. SUR2A in heart) of the bipartite channel complex. To examine this, we have generated transgenic (TG) mice that overexpress epitope-tagged SUR1 or SUR2A under the transcriptional control of the alpha-myosin heavy chain promoter. Western blot and real time RT-PCR analysis confirm transgene expression in the heart, and variable levels of SUR1 RNA and protein, in 16 viable founder lines. Surprisingly, activation of channels by either pharmacological agents (diazoxide and pinacidil) or metabolic inhibitors (oligomycin and 2-deoxyglucose) reveals a suppression of total K(ATP) conductance in high expressing TG mice. Moreover, K(ATP) channel activity was significantly reduced in excised cardiac patches from TG myocytes that overexpress either SUR1 or SUR2A. Using a recombinant cell system, we show that overexpression of either SUR1 or Kir6.2 suppresses the functional expression of K(ATP) from optimized dimeric SUR1-Kir6.2. Thus, the graded effect of SUR1 expression in the intact heart appears to demonstrate an in vivo requirement for 1:1 expression ratio of Kir6.2 and SURx.

  4. Innovative hybrid biological reactors using membranes; Reactores biologico hibrido innovadores utilizando membranas

    Energy Technology Data Exchange (ETDEWEB)

    Diez, R.; Esteban-Garcia, A. L.; Florio, L. de; Rodriguez-Hernandez, L.; Tejero, I.

    2011-07-01

    In this paper we present two lines of research on hybrid reactors including the use of membranes, although with different functions: RBPM, biofilm reactors and membranes filtration RBSOM, supported biofilm reactors and oxygen membranes. (Author) 14 refs.

  5. Establishment of licensing process for development reactors

    Energy Technology Data Exchange (ETDEWEB)

    Jo, Jong Chull; Yune, Young Gill; Kim, Woong Sik (and others)

    2006-02-15

    A study on licensing processes for development reactors has been performed to prepare the licensing of development reactors developed in Korea. The contents and results of the study are summarized as follows. The licensing processes for nuclear reactors in Korea, U.S.A., Japan, France, U.K., Canada, and IAEA were surveyed and analyzed to obtain technical bases necessary for establishing licensing processes applicable to development reactors in Korea. Based on the technical bases obtained the above analysis, the purpose, power output, and design characteristics of development reactors were analyzed in detail. The analysis results suggested that development reactors should be classified as a new reactor category (called as 'development reactor') separated from the current reactor categories such as the research reactor and the power reactor. Therefore, it is proposed to establish a new reactor category classified as 'development reactor' for the development reactors. And licensing processes, including licensing technical requirements, licensing document requirements, and other regulatory requirements, were also proposed for the development reactors. In order to institutionalize the licensing processes developed in this study, it is necessary to revise the current laws. Therefore, draft provisions of Atomic Energy Act, Enforcement Decree of the Atomic Energy Act, and Enforcement Regulation of the Atomic Energy Act have been developed for the preparation of the future legalization of the licensing processes proposed for the development reactors. Conclusively, a proposal of licensing processes and draft provisions of laws have been developed for the development reactors. The results proposed in this study can be applied directly to the licensing of the future development reactors. Furthermore, they will also contribute to establishing successfully the licensing processes of the development reactors.

  6. Repairing liner of the reactor; Reparacion del liner del reactor

    Energy Technology Data Exchange (ETDEWEB)

    Aguilar H, F. [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico)

    2001-07-15

    Due to the corrosion problems of the aluminum coating of the reactor pool, a periodic inspections program by ultrasound to evaluate the advance grade and the corrosion speed was settled down. This inspections have shown the necessity to repair some areas, in those that the slimming is significant, of not making it can arrive to the water escape of the reactor pool. The objective of the repair is to place patches of plates of 1/4 inch aluminum thickness in the areas of the reactor 'liner', in those that it has been detected by ultrasound a smaller thickness or similar to 3 mm. To carry out this the fuels are move (of the core and those that are decaying) to a temporary storage, the structure of the core is confined in a tank that this placed inside the pool of the reactor, a shield is placed in the thermal column and it is completely extracted the water for to leave uncover the 'liner' of the reactor. (Author)

  7. Reactor Simulator Testing

    Science.gov (United States)

    Schoenfeld, Michael P.; Webster, Kenny L.; Pearson, Boise Jon

    2013-01-01

    As part of the Nuclear Systems Office Fission Surface Power Technology Demonstration Unit (TDU) project, a reactor simulator test loop (RxSim) was design & built to perform integrated testing of the TDU components. In particular, the objectives of RxSim testing was to verify the operation of the core simulator, the instrumentation and control system, and the ground support gas and vacuum test equipment. In addition, it was decided to include a thermal test of a cold trap purification design and a pump performance test at pump voltages up to 150 V since the targeted mass flow rate of 1.75 kg/s was not obtained in the RxSim at the originally constrained voltage of 120 V. This paper summarizes RxSim testing. The gas and vacuum ground support test equipment performed effectively in NaK fill, loop pressurization, and NaK drain operations. The instrumentation and control system effectively controlled loop temperature and flow rates or pump voltage to targeted settings. The cold trap design was able to obtain the targeted cold temperature of 480 K. An outlet temperature of 636 K was obtained which was lower than the predicted 750 K but 156 K higher than the cold temperature indicating the design provided some heat regeneration. The annular linear induction pump (ALIP) tested was able to produce a maximum flow rate of 1.53 kg/s at 800 K when operated at 150 V and 53 Hz. Keywords: fission, space power, nuclear, liquid metal, NaK.

  8. Reactivity determination in accelerator driven reactors using reactor noise analysis

    Directory of Open Access Journals (Sweden)

    Kostić Ljiljana 1

    2002-01-01

    Full Text Available Feynman-alpha and Rossi-alpha methods are used in traditional nuclear reactors to determine the subcritical reactivity of a system. The methods are based on the measurement of the mean value, variance and the covariance of detector counts for different measurement times. Such methods attracted renewed attention recently with the advent of the so-called accelerator driven reactors (ADS proposed some time ago. The ADS systems, intended to be used either in energy generation or transuranium transmutation, will use a subcritical core with a strong spallation source. A spallation source has statistical properties that are different from those traditionally used by radioactive sources. In such reactors the monitoring of the subcritical reactivity is very important, and a statistical method, such as the Feynman-alpha method, is capable of resolving this problem.

  9. Heterogeneous Transmutation Sodium Fast Reactor

    Energy Technology Data Exchange (ETDEWEB)

    S. E. Bays

    2007-09-01

    The threshold-fission (fertile) nature of Am-241 is used to destroy this minor actinide by capitalizing upon neutron capture instead of fission within a sodium fast reactor. This neutron-capture and its subsequent decay chain leads to the breeding of even neutron number plutonium isotopes. A slightly moderated target design is proposed for breeding plutonium in an axial blanket located above the active “fast reactor” driver fuel region. A parametric study on the core height and fuel pin diameter-to-pitch ratio is used to explore the reactor and fuel cycle aspects of this design. This study resulted in both non-flattened and flattened core geometries. Both of these designs demonstrated a high capacity for removing americium from the fuel cycle. A reactivity coefficient analysis revealed that this heterogeneous design will have comparable safety aspects to a homogeneous reactor of comparable size. A mass balance analysis revealed that the heterogeneous design may reduce the number of fast reactors needed to close the current once-through light water reactor fuel cycle.

  10. Thermonuclear Reflect AB-Reactor

    CERN Document Server

    Bolonkin, Alexander

    2008-01-01

    The author offers a new kind of thermonuclear reflect reactor. The remarkable feature of this new reactor is a three net AB reflector, which confines the high temperature plasma. The plasma loses part of its energy when it contacts with the net but this loss can be compensated by an additional permanent plasma heating. When the plasma is rarefied (has a small density), the heat flow to the AB reflector is not large and the temperature in the triple reflector net is lower than 2000 - 3000 K. This offered AB-reactor has significantly less power then the currently contemplated power reactors with magnetic or inertial confinement (hundreds-thousands of kW, not millions of kW). But it is enough for many vehicles and ships and particularly valuable for tunnelers, subs and space apparatus, where air to burn chemical fuel is at a premium or simply not available. The author has made a number of innovations in this reactor, researched its theory, developed methods of computation, made a sample computation of typical pr...

  11. Imaging Fukushima Daiichi reactors with muons

    Directory of Open Access Journals (Sweden)

    Haruo Miyadera

    2013-05-01

    Full Text Available A study of imaging the Fukushima Daiichi reactors with cosmic-ray muons to assess the damage to the reactors is presented. Muon scattering imaging has high sensitivity for detecting uranium fuel and debris even through thick concrete walls and a reactor pressure vessel. Technical demonstrations using a reactor mockup, detector radiation test at Fukushima Daiichi, and simulation studies have been carried out. These studies establish feasibility for the reactor imaging. A few months of measurement will reveal the spatial distribution of the reactor fuel. The muon scattering technique would be the best and probably the only way for Fukushima Daiichi to make this determination in the near future.

  12. Fast breeder reactors an engineering introduction

    CERN Document Server

    Judd, A M

    1981-01-01

    Fast Breeder Reactors: An Engineering Introduction is an introductory text to fast breeder reactors and covers topics ranging from reactor physics and design to engineering and safety considerations. Reactor fuels, coolant circuits, steam plants, and control systems are also discussed. This book is comprised of five chapters and opens with a brief summary of the history of fast reactors, with emphasis on international and the prospect of making accessible enormous reserves of energy. The next chapter deals with the physics of fast reactors and considers calculation methods, flux distribution,

  13. SUR1-Associated Mechanisms Are Not Involved in Ischemic Optic Neuropathy 1 Day Post-Injury.

    Science.gov (United States)

    Nicholson, James D; Guo, Yan; Bernstein, Steven L

    2016-01-01

    Ischemia-reperfusion injury after central nervous system (CNS) injury presents a major health care challenge with few promising treatments. Recently, it has become possible to reduce edema after CNS injury by antagonizing a sulfonylurea receptor 1 (SUR1) regulated ion channel expressed after injury. SUR1 upregulation after injury is a necessary precondition for the formation of this channel, and has been implicated in white matter injury after clinical spinal cord trauma. Glibenclamide, an SUR1 antagonist, appears to have neuroprotective effect against cerebral stroke in an open-label small clinical trial and great effectiveness in reducing damage after varied experimental CNS injury models. Despite its importance in CNS injuries, SUR1 upregulation appears to play no part in rodent anterior ischemic optic neuropathy (rAION) injury as tested by real-time PCR and immunohistochemical staining of rAION-injured rat optic nerve (ON). Furthermore, the SUR1 antagonist glibenclamide administered immediately after rAION injury provided no protection to proximal ON microvasculature 1 day post-injury but may reduce optic nerve head edema in a manner unrelated to ON SUR1 expression. Our results suggest that there may be fundamental differences between rAION optic nerve ischemia and other CNS white matter injuries where SUR1 appears to play a role.

  14. « Sur la pyrotechnie »

    OpenAIRE

    Vinci , Léonard de

    2008-01-01

    Sur les effets pyrotechniques dans la réalitéSi tu veux allumer dans une vaste pièce une flambée qui ne cause aucun dommage, fais ainsi : d'abord, parfume l'air avec une épaisse vapeur d'encens ou quelque autre senteur fortement odorante, puis souffle, ou fait bouillir, et réduis à l'état de vapeur, dix livres d'eau-de-vie. Prends garde toutefois que la pièce soit bien close, et jette à travers la fumée, du vernis pulvérisé, qui flottera au-dessus d'elle ; puis, muni d'une torche, entre brusq...

  15. Le dernier Wittgenstein et le dernier Husserl sur le langage

    Directory of Open Access Journals (Sweden)

    Paul Ricoeur

    2014-07-01

    Full Text Available This article presents an edited version of lectures given by Paul Ricœur at Johns Hopkins University in April 1966. Ricœur offers a comparative analysis of Wittgenstein’s and Husserl’s late works, taking the problem of language as the common ground of investigation for these two central figures of phenomenology and analytic philosophy. Ricœur develops his study in two parts. The first part considers Husserl’s approach to language after the Logical Investigations and concentrates on Formal and Transcendental Logic; leaving a transcendental reflection on language behind it re-examines a phenomenological conception, according to which the sphere of logic is not separable from that of experience. The main focus of the second part is Wittgenstein’s later philosophy as it moved on from the conception of an isomorphic relation between language and the world, as set out in the picture theory in the Tractatus Logico-Philosophicus, to the more pragmatic notion of a language-game in the Philosophical Investigations. In order to get beyond the irrevocable differences between the two philosophies and the unresolved theoretical issues on both sides, Ricœur suggests turning to a semiological paradigm based on the Saussurean distinction between “language” and “speaking.” Keyword: Analytic Philosophy, Husserl, Phenomenology, Semiology, Wittgenstein.  Résumé Cet article est une version éditée de conférences données par Paul Ricœur à la Johns Hopkins University en avril 1966. Ricœur propose une analyse comparée des dernières œuvres de Wittgenstein et Husserl, avec le problème du langage comme sol commun d’investigations pour ces deux figures centrales de la phénoménologie et la philosophie analytique. Cette analyse de Ricœur se joue à travers deux parties. La première partie revient sur l'approche du langage chez Husserl depuis Recherches logiques avec une attention particulière aux développements de Logique formelle et

  16. Uruguay: el sur también existe

    OpenAIRE

    Carmen Morente Muñoz

    2013-01-01

    La República Oriental del Uruguay resulta un país bastante desconocido. Creador del primer “Estado del Bienestar”, a principios del siglo XX, sus particularidades no lo hacen tan distinto al resto de países de América Latina. Padeció la dictadura más cruenta del Cono Sur y las inclemencias de las políticas neoliberales. En 2004, el Frente Amplio, conquista la mayoría parlamentaria y el gobierno, abriendo un camino de esperanzas y de reconstrucción económica y social. A través de sus políticas...

  17. Bordeaux parie sur les centres d’appels

    Directory of Open Access Journals (Sweden)

    Gilles Puel

    2003-06-01

    Full Text Available Les acteurs territoriaux de la métropole bordelaise ont parié depuis peu sur le développement des centres d’appels en dépit d’une concurrence de plus en plus vive et planétaire. Les logiques de localisation des entreprises favorisent la métropolisation des téléservices. L’espace métropolitain privilégié par cet aspect de la « nouvelle économie » est en périphérie urbaine dans les zones d’activités à proximité des grands réseaux de communication (rocades, aéroports, etc..

  18. Commentaires sur la valeur piscicole du Canal de Roubaix (Nord

    Directory of Open Access Journals (Sweden)

    ARRIGNON J.

    1970-10-01

    Full Text Available La population piscicole du Canal de ROUBAIX a été inventoriée par pêche électrique. Trois passages, suivis chacun de l'enlèvement des poissons capturés, ont été opérés dans chacun des trois Secteurs d'inventaire. Le peuplement le plus probable ainsi estimé (par la méthode De Lury,est en rapport avec le degré de pollution du canal. On constate aussi queles poissons se cantonnent le long des berges, sur une largeur de 2 à 3mètres.L'estimation à l'hectare représente donc en réalité le stock d'une zone n'ayant que 25 % de la surface totale du Canal. Les poissons contrôlés sont pour la plupart des poissons de repeuplement.

  19. Sur le(s temps en sciences sociales

    Directory of Open Access Journals (Sweden)

    Florence Lacoma Iborra

    2011-11-01

    Full Text Available À l’initiative du Centre Norbert Elias, la première journée d’étude d’un cycle annuel, centrée sur la question du temps en sciences sociales, s’est tenue dans les locaux de l‘université d’Avignon le 21 octobre 2011.Cette journée délibérément pluridisciplinaire a favorisé la confrontation d’expériences temporelles différentes issues de champs de recherches distincts et forts éloignés (le temps discursif, la temporalité médiatique, le temps patrimonial, mais aussi la mise en regard de représen...

  20. Un copiste inattendu à Vic-sur-Cère (Cantal

    Directory of Open Access Journals (Sweden)

    Renaud Benoit-Cattin

    2012-02-01

    Full Text Available A Vic-sur-Cère, petit bourg du Cantal, l’hôtel du Pont et du Parc abrite au rez-de-chaussée une salle de restaurant dont les quatre murs sont ornés de dix-sept peintures d’un caractère peu ou prou monumental. Leur hauteur est d’environ 1,50 m, leur largeur variant de 0,6 à 3,5 m. Quatorze d’entre elles ont été exécutées par Antoine Cayrol entre 1909 et 1914, les trois dernières par son petit-fils, Roger Cayrol, en 1954.Le grand-père, Antoine, né en 1864, est élevé à Paris. Après son service m...

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

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1968-07-01

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

  2. The Production of the Pastora in Camarines Sur, Philippines

    Directory of Open Access Journals (Sweden)

    JIYE A. MARGATE

    2014-04-01

    Full Text Available The purpose of the study was to document the pastora, a song-dance performance during Christmas season that calls to celebrate the birth of Jesus Christ in two towns of Camarines Sur, Philippines. Specifically, it focused on its production aspect. The categories include: the handing down of oral traditions which influenced the trainers' casting, choreography, costumes, props, musical accompaniment, and performances. The researcher made use of real time data: videotaped pastora dances, observer’s notes, ex post facto data: stimulated recall and interviews. There were similarities and differences in the production of these pastora. Both of the trainers were exposed to this activity at a young age. At present, their granddaughters are members of their respective pastora groups—one way of handing down the oral tradition to the younger generations. Both groups have dresses made of silks and laces. With regard to the choice of colors, Mimay prefers to use light colors such as white, light blue, and pink while Rita favors loud colors such as red, green, and golden yellow. At present they use only one kind of musical instrument in their pastora. Pastora Baao uses a saxophone while pastora Bombon uses a guitar. The trainers also differ in standards for recruiting members. Mimay prefers to invite girls with good singing voice, good dancing ability, and good physical appearance, while Rita believes that willingness is the most important quality of a pastora. The similarities in the production of these pastora reveal the possibility that pastora in Camarines Sur came from one source. The similarities also revealed the impact of pastora in maintaining religiosity and the socio-cultural environment. The differences are influenced by the tradition handed down to trainers, the trainers’ personal outlook, geographical locations, and economic condition.

  3. Components of SurA required for outer membrane biogenesis in uropathogenic Escherichia coli.

    Directory of Open Access Journals (Sweden)

    Kristin M Watts

    Full Text Available BACKGROUND: SurA is a periplasmic peptidyl-prolyl isomerase (PPIase and chaperone of Escherichia coli and other Gram-negative bacteria. In contrast to other PPIases, SurA appears to have a distinct role in chaperoning newly synthesized porins destined for insertion into the outer membrane. Previous studies have indicated that the chaperone activity of SurA rests in its "core module" (the N- plus C-terminal domains, based on in vivo envelope phenotypes and in vitro binding and protection of non-native substrates. METHODOLOGY/PRINCIPAL FINDINGS: In this study, we determined the components of SurA required for chaperone activity using in vivo phenotypes relevant to disease causation by uropathogenic E. coli (UPEC, namely membrane resistance to permeation by antimicrobials and maturation of the type 1 pilus usher FimD. FimD is a SurA-dependent, integral outer membrane protein through which heteropolymeric type 1 pili, which confer bladder epithelial binding and invasion capacity upon uropathogenic E. coli, are assembled and extruded. Consistent with prior results, the in vivo chaperone activity of SurA in UPEC rested primarily in the core module. However, the PPIase domains I and II were not expendable for wild-type resistance to novobiocin in broth culture. Steady-state levels of FimD were substantially restored in the UPEC surA mutant complemented with the SurA N- plus C-terminal domains. The addition of PPIase domain I augmented FimD maturation into the outer membrane, consistent with a model in which domain I enhances stability of and/or substrate binding by the core module. CONCLUSIONS/SIGNIFICANCE: Our results confirm the core module of E. coli SurA as a potential target for novel anti-infective development.

  4. HMR 1098 is not an SUR isotype specific inhibitor of heterologous or sarcolemmal K ATP channels.

    Science.gov (United States)

    Zhang, Hai Xia; Akrouh, Alejandro; Kurata, Harley T; Remedi, Maria Sara; Lawton, Jennifer S; Nichols, Colin G

    2011-03-01

    Murine ventricular and atrial ATP-sensitive potassium (K(ATP)) channels contain different sulfonylurea receptors (ventricular K(ATP) channels are Kir6.2/SUR2A complexes, while atrial K(ATP) channels are Kir6.2/SUR1 complexes). HMR 1098, the sodium salt of HMR 1883 {1-[[5-[2-(5-chloro-o-anisamido)ethyl]-2-methoxyphenyl]sulfonyl]-3-methylthiourea}, has been considered as a selective sarcolemmal (i.e. SUR2A-dependent) K(ATP) channel inhibitor. However, it is not clear whether HMR 1098 would preferentially inhibit ventricular K(ATP) channels over atrial K(ATP) channels. To test this, we used whole-cell patch clamp techniques on mouse atrial and ventricular myocytes as well as (86)Rb(+) efflux assays and excised inside-out patch clamp techniques on Kir6.2/SUR1 and Kir6.2/SUR2A channels heterologously expressed in COSm6 cells. In mouse atrial myocytes, both spontaneously activated and diazoxide-activated K(ATP) currents were effectively inhibited by 10 μM HMR 1098. By contrast, in ventricular myocytes, pinacidil-activated K(ATP) currents were inhibited by HMR 1098 at a high concentration (100 μM) but not at a low concentration (10 μM). Consistent with this finding, HMR 1098 inhibits (86)Rb(+) effluxes through Kir6.2/SUR1 more effectively than Kir6.2/SUR2A channels in COSm6 cells. In excised inside-out patches, HMR 1098 inhibited Kir6.2/SUR1 channels more effectively, particularly in the presence of MgADP and MgATP (mimicking physiological stimulation). Finally, dose-dependent enhancement of insulin secretion from pancreatic islets and decrease of blood glucose level confirm that HMR 1098 is an inhibitor of Kir6.2/SUR1-composed K(ATP) channels.

  5. Plasma reactor waste management systems

    Science.gov (United States)

    Ness, Robert O., Jr.; Rindt, John R.; Ness, Sumitra R.

    1992-01-01

    The University of North Dakota is developing a plasma reactor system for use in closed-loop processing that includes biological, materials, manufacturing, and waste processing. Direct-current, high-frequency, or microwave discharges will be used to produce plasmas for the treatment of materials. The plasma reactors offer several advantages over other systems, including low operating temperatures, low operating pressures, mechanical simplicity, and relatively safe operation. Human fecal material, sunflowers, oats, soybeans, and plastic were oxidized in a batch plasma reactor. Over 98 percent of the organic material was converted to gaseous products. The solids were then analyzed and a large amount of water and acid-soluble materials were detected. These materials could possibly be used as nutrients for biological systems.

  6. Nuclear Reactor Engineering Analysis Laboratory

    Energy Technology Data Exchange (ETDEWEB)

    Carlos Chavez-Mercado; Jaime B. Morales-Sandoval; Benjamin E. Zayas-Perez

    1998-12-31

    The Nuclear Reactor Engineering Analysis Laboratory (NREAL) is a sophisticated computer system with state-of-the-art analytical tools and technology for analysis of light water reactors. Multiple application software tools can be activated to carry out different analyses and studies such as nuclear fuel reload evaluation, safety operation margin measurement, transient and severe accident analysis, nuclear reactor instability, operator training, normal and emergency procedures optimization, and human factors engineering studies. An advanced graphic interface, driven through touch-sensitive screens, provides the means to interact with specialized software and nuclear codes. The interface allows the visualization and control of all observable variables in a nuclear power plant (NPP), as well as a selected set of nonobservable or not directly controllable variables from conventional control panels.

  7. Utilisation of thorium in reactors

    Science.gov (United States)

    Anantharaman, K.; Shivakumar, V.; Saha, D.

    2008-12-01

    India's nuclear programme envisages a large-scale utilisation of thorium, as it has limited deposits of uranium but vast deposits of thorium. The large-scale utilisation of thorium requires the adoption of closed fuel cycle. The stable nature of thoria and the radiological issues associated with thoria poses challenges in the adoption of a closed fuel cycle. A thorium fuel based Advanced Heavy Water Reactor (AHWR) is being planned to provide impetus to development of technologies for the closed thorium fuel cycle. Thoria fuel has been loaded in Indian reactors and test irradiations have been carried out with (Th-Pu) MOX fuel. Irradiated thorium assemblies have been reprocessed and the separated 233U fuel has been used for test reactor KAMINI. The paper highlights the Indian experience with the use of thorium and brings out various issues associated with the thorium cycle.

  8. A tubular focused sonochemistry reactor

    Institute of Scientific and Technical Information of China (English)

    ZHOU GuangPing; LIANG ZhaoFeng; LI ZhengZhong; ZHANG YiHui

    2007-01-01

    This paper presents a new sonochemistry reactor, which consists of a cylindrical tube with a certain length and piezoelectric transducers at tube's end with the longitudinal vibration. The tube can effectively transform the longitudinal vibration into the radial vibration and thereby generates ultrasound. Furthermore, ultrasound can be focused to form high-intensity ultrasonic field inside tube. The reactor boasts of simple structure and its whole vessel wall can radiate ultrasound so that the electroacoustic transfer efficiency is high. The focused ultrasonic field provides good condition for sonochemical reaction. The length of the reactor can be up to 2 meters, and liquids can pass through it continuously, so it can be widely applied in liquid processing such as sonochemistry.

  9. A compact Tokamak transmutation reactor

    Institute of Scientific and Technical Information of China (English)

    QiuLi-Jian; XiaoBing-Jia

    1997-01-01

    The low aspect ration tokamak is proposed for the driver of a transmutation reactor.The main parameters of the reactor core,neutronic analysis of the blanket are given>the neutron wall loading can be lowered from the magnitude order of 1 MW/m2 to 0.5MW/m2 which is much easier to reach in the near future,and the transmutation efficiency (fission/absorption ratio)is raised further.The blanket power density is about 200MW/m3 which is not difficult to deal with.The key components such as diverter and center conductor post are also designed and compared with conventional TOkamak,Finally,by comparison with the other drivers such as FBR,PWR and accelerator,it can be anticipated that the low aspect ratio transmutation reactor would be one way of fusion energy applications in the near future.

  10. Investigation of KW reactor incident

    Energy Technology Data Exchange (ETDEWEB)

    Sturges, D G [USAEC Hanford Operations Office, Richland, WA (United States); Hauff, T W; Greager, O H [General Electric Co., Richland, WA (United States). Hanford Atomic Products Operation

    1955-02-11

    The new KW reactor was placed in operation on January 4, 1955, and had been running at relatively low power levels for only 17 hours when it was shut down because of a process tube water leak which appeared to be associated with a slug rupture. After several days of unrewarding effort to remove the slugs and tube by customary methods, it developed that considerable melting of the tube and slugs had taken place. It was then evident that removal of the stuck mass and repairs to the damaged tube channel would require unusual measures that were certain to extend the reactor outage for several weeks. This report documents the work and findings of the Committee which investigated the KW reactor incident. Its content represents unanimous agreement among the three Committee members.

  11. Les leaders d'opinion sur les réseaux socionumériques

    OpenAIRE

    Camille Alloing; Marie Haikel-Elsabeh

    2012-01-01

    L'une des problématiques des entreprises investissant dans les campagnes marketing sur les réseaux sociaux numériques est de déterminer une population cible qui a une capacité de diffusion et de médiatisation identifiable. Le concept de leader d'opinion semble de prime abord répondre aux caractéristiques souhaitées par les entreprises pour des actions marketing sur Internet. Seulement, les leaders d'opinions sont-ils les seuls usagers d'Internet à pouvoir influer sur les cibles de l'entrepris...

  12. Fundamentals of Nuclear Reactor Physics

    CERN Document Server

    Lewis, E E

    2008-01-01

    This new streamlined text offers a one-semester treatment of the essentials of how the fission nuclear reactor works, the various approaches to the design of reactors, and their safe and efficient operation. The book includes numerous worked-out examples and end-of-chapter questions to help reinforce the knowledge presented. This textbook offers an engineering-oriented introduction to nuclear physics, with a particular focus on how those physics are put to work in the service of generating nuclear-based power, particularly the importance of neutron reactions and neutron behavior. Engin

  13. PITR: Princeton Ignition Test Reactor

    Energy Technology Data Exchange (ETDEWEB)

    1978-12-01

    The principal objectives of the PITR - Princeton Ignition Test Reactor - are to demonstrate the attainment of thermonuclear ignition in deuterium-tritium, and to develop optimal start-up techniques for plasma heating and current induction, in order to determine the most favorable means of reducing the size and cost of tokamak power reactors. This report describes the status of the plasma and engineering design features of the PITR. The PITR geometry is chosen to provide the highest MHD-stable values of beta in a D-shaped plasma, as well as ease of access for remote handling and neutral-beam injection.

  14. Analysis of Adiabatic Batch Reactor

    Directory of Open Access Journals (Sweden)

    Erald Gjonaj

    2016-05-01

    Full Text Available A mixture of acetic anhydride is reacted with excess water in an adiabatic batch reactor to form an exothermic reaction. The concentration of acetic anhydride and the temperature inside the adiabatic batch reactor are calculated with an initial temperature of 20°C, an initial temperature of 30°C, and with a cooling jacket maintaining the temperature at a constant of 20°C. The graphs of the three different scenarios show that the highest temperatures will cause the reaction to occur faster.

  15. External fuel thermionic reactor system.

    Science.gov (United States)

    Mondt, J. F.; Peelgren, M. L.

    1971-01-01

    Thermionic reactors are prime candidates for nuclear electric propulsion. The national thermionic reactor effort is concentrated on the flashlight concept with the external-fuel concept as the backup. The external-fuel concept is very adaptable to a completely modular power subsystem which is attractive for highly reliable long-life applications. The 20- to 25-cm long, externally-fueled converters have been designed, fabricated, and successfully tested with many thermal cycles by electrical heating. However, difficulties have been encountered during encapsulation for nuclear heated tests and none have been started to date. These nuclear tests are required to demonstrate the concept feasibility.

  16. Reactor shutdown delays medical procedures

    Science.gov (United States)

    Gwynne, Peter

    2008-01-01

    A longer-than-expected maintenance shutdown of the Canadian nuclear reactor that produces North America's entire supply of molybdenum-99 - from which the radioactive isotopes technetium-99 and iodine-131 are made - caused delays to the diagnosis and treatment of thousands of seriously ill patients last month. Technetium-99 is a key component of nuclear-medicine scans, while iodine-131 is used to treat cancer and other diseases of the thyroid. Production eventually resumed, but only after the Canadian government had overruled the Canadian Nuclear Safety Commission (CNSC), which was still concerned about the reactor's safety.

  17. Request for Naval Reactors Comment on Proposed Prometheus Space Flight Nuclear Reactor High Tier Reactor Safety Requirements and for Naval Reactors Approval to Transmit These Requirements to JPL

    Energy Technology Data Exchange (ETDEWEB)

    D. Kokkinos

    2005-04-28

    The purpose of this letter is to request Naval Reactors comments on the nuclear reactor high tier requirements for the PROMETHEUS space flight reactor design, pre-launch operations, launch, ascent, operation, and disposal, and to request Naval Reactors approval to transmit these requirements to Jet Propulsion Laboratory to ensure consistency between the reactor safety requirements and the spacecraft safety requirements. The proposed PROMETHEUS nuclear reactor high tier safety requirements are consistent with the long standing safety culture of the Naval Reactors Program and its commitment to protecting the health and safety of the public and the environment. In addition, the philosophy on which these requirements are based is consistent with the Nuclear Safety Policy Working Group recommendations on space nuclear propulsion safety (Reference 1), DOE Nuclear Safety Criteria and Specifications for Space Nuclear Reactors (Reference 2), the Nuclear Space Power Safety and Facility Guidelines Study of the Applied Physics Laboratory.

  18. Oregon State University TRIGA Reactor annual report

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, T.V.; Johnson, A.G.; Bennett, S.L.; Ringle, J.C.

    1979-08-31

    The use of the Oregon State University TRIGA Reactor during the year ending June 30, 1979, is summarized. Environmental and radiation protection data related to reactor operation and effluents are included.

  19. Reactor Antineutrino Signals at Morton and Boulby

    CERN Document Server

    Dye, Steve

    2016-01-01

    Increasing the distance from which an antineutrino detector is capable of monitoring the operation of a registered reactor, or discovering a clandestine reactor, strengthens the Non-Proliferation of Nuclear Weapons Treaty. This report presents calculations of reactor antineutrino interactions, from quasi-elastic neutrino-proton scattering and elastic neutrino-electron scattering, in a water-based detector operated >10 km from a commercial power reactor. It separately calculates signal from the proximal reactor and background from all other registered reactors. The main results are interaction rates and kinetic energy distributions of charged leptons scattered from quasi-elastic and elastic processes. Comparing signal and background distributions evaluates reactor monitoring capability. Scaling the results to detectors of different sizes, target media, and standoff distances is straightforward. Calculations are for two examples of a commercial reactor (P_th~3 GW) operating nearby (L~20 km) an underground facil...

  20. About Chernobyl - Twenty Years Later; Propos sur Tchernobyl

    Energy Technology Data Exchange (ETDEWEB)

    Tubiana, M

    2006-07-01

    The author discusses the reactor accident of Chernobyl, the information on its consequences so contradictory in the former USSR countries, the status of the effects observed, the forecasting concerning the onset of cancers in the coming years among the populations that were exposed to radiations, the public opinion facing the pessimists. He concludes on the lessons which can be drawn from Chernobyl. (A.L.B.)

  1. Transmutation of actinides in power reactors.

    Science.gov (United States)

    Bergelson, B R; Gerasimov, A S; Tikhomirov, G V

    2005-01-01

    Power reactors can be used for partial short-term transmutation of radwaste. This transmutation is beneficial in terms of subsequent storage conditions for spent fuel in long-term storage facilities. CANDU-type reactors can transmute the main minor actinides from two or three reactors of the VVER-1000 type. A VVER-1000-type reactor can operate in a self-service mode with transmutation of its own actinides.

  2. Laminar Entrained Flow Reactor (Fact Sheet)

    Energy Technology Data Exchange (ETDEWEB)

    2014-02-01

    The Laminar Entrained Flow Reactor (LEFR) is a modular, lab scale, single-user reactor for the study of catalytic fast pyrolysis (CFP). This system can be employed to study a variety of reactor conditions for both in situ and ex situ CFP.

  3. Some new viewpoints in reactor noise analysis

    Institute of Scientific and Technical Information of China (English)

    罗征培; 李富; 等

    1996-01-01

    It is propsed that the linearity criterion and order criterion via frequency spectrum features without any limitation of the model's phase can be used in reactor noise analysis.The time constant,natural frequency as well as the recovered transfer function of reactors can bhe obtained via the analyzable model based on reactor noise.

  4. Heat-pipe thermionic reactor concept

    DEFF Research Database (Denmark)

    Storm Pedersen, E.

    1967-01-01

    Main components are reactor core, heat pipe, thermionic converter, secondary cooling system, and waste heat radiator; thermal power generated in reactor core is transported by heat pipes to thermionic converters located outside reactor core behind radiation shield; thermionic emitters are in direct...

  5. Heavy Water Reactor; Reacteurs a eau lourde

    Energy Technology Data Exchange (ETDEWEB)

    Yu, St.; HOpwood, J.; Meneley, D. [Energie Atomique du Canada (Canada)

    2000-04-01

    This document deals with the Heavy Water Reactor (HWR) technology and especially the Candu (Canada Deuterium Uranium) reactor. This reactors type offers many advantages that promote them for the future. General concepts, a description of the Candu nuclear power plants, the safety systems, the fuel cycle and economical and environmental aspects are included. (A.L.B.)

  6. Operating Modes Of Chemical Reactors Of Polymerization

    Directory of Open Access Journals (Sweden)

    Meruyert Berdieva

    2012-05-01

    Full Text Available In the work the issues of stable technological modes of operation of main devices of producing polysterol reactors have been researched as well as modes of stable operation of a chemical reactor have been presented, which enables to create optimum mode parameters of polymerization process, to prevent emergency situations of chemical reactor operation in industrial conditions.

  7. Nuclear Reactors and Technology; (USA)

    Energy Technology Data Exchange (ETDEWEB)

    Cason, D.L.; Hicks, S.C. (eds.)

    1991-01-01

    Nuclear Reactors and Technology (NRT) announces on a monthly basis the current worldwide information available from the open literature on nuclear reactors and technology, including all aspects of power reactors, components and accessories, fuel elements, control systems, and materials. This publication contains the abstracts of DOE reports, journal articles, conference papers, patents, theses, and monographs added to the Energy Science and Technology Database (EDB) during the past month. Also included are US information obtained through acquisition programs or interagency agreements and international information obtained through the International Energy Agency's Energy Technology Data Exchange or government-to-government agreements. The digests in NRT and other citations to information on nuclear reactors back to 1948 are available for online searching and retrieval on EDB and Nuclear Science Abstracts (NSA) database. Current information, added daily to EDB, is available to DOE and its contractors through the DOE integrated Technical Information System. Customized profiles can be developed to provide current information to meet each user's needs.

  8. A Simple Tubular Reactor Experiment.

    Science.gov (United States)

    Hudgins, Robert R.; Cayrol, Bertrand

    1981-01-01

    Using the hydrolysis of crystal violet dye by sodium hydroxide as an example, the theory, apparatus, and procedure for a laboratory demonstration of tubular reactor behavior are described. The reaction presented can occur at room temperature and features a color change to reinforce measured results. (WB)

  9. Silica-Immobilized Enzyme Reactors

    Science.gov (United States)

    2007-08-01

    immobilized artificial membrane chromatography and lysophospholipid micellar electrokinetic chromatography . J. Chromatogr. A 1998, 810, 95-103. 50...Journal of Liquid Chromatography and Related Technologies. Air Force Research Laboratory Materials and Manufacturing Directorate Airbase...immobilized enzyme reactors (IMERs) can also be integrated directly to further analytical methods such as liquid chromatography or mass spectrometry.[6] In

  10. British high flux beam reactor.

    Science.gov (United States)

    Egelstaff, P A

    1970-10-24

    The neutron scattering technique has become an accepted method for the study of condensed matter. Because of the great scientific and technical value of neutron experiments and the growing body of users, several proposals have been made during the past decade for a nuclear reactor devoted primarily to this technique. This article reviews the reasons for and history behind these proposals.

  11. L'UOIF:en face de la loi sur la la(i)cité

    Institute of Scientific and Technical Information of China (English)

    田俊雷; 申永杰

    2004-01-01

    La socié té francaise se caracté rise par le principe de la(i)cité. 《 L' affaire du foulard 》 existe en France depuisquelques anné es. Pour 1' instant, la question du voile se focalise sur les lycé es et sur quelques les colle ges. Le voile a causé un dé sé quilibre a 1'é cole. La France est cette socié té multiculturelle. Dans ce dossier, on pré sente la motivation et 1' objet dudossier en introduction. Ensuite dans deux parties distinctes, on dé crit le panorama des articles et on les analyse. Dans une autrepartie, on de veloppe son argumentation sur le sujet, et pour finir, la conclusion sur 1' objet du dossier.

  12. Pärt, Arvo: "Summa". Collage sur BACH. Fratres / Patric Wiklacz

    Index Scriptorium Estoniae

    Wiklacz, Patric

    1997-01-01

    Uuest heliplaadist "Pärt, Arvo: "Summa". Collage sur BACH. Fratres. Cantus in Memoriam Benjamin Britten. Summa. Festina Lente. Tabula rasa. Tapiola Sinfonietta / Jean-Jacques Kantorow". BIS-CD-834. 62:30 DDD

  13. Bibliography on plutonium and its compounds; Bibliographie sur le plutonium et ses composes

    Energy Technology Data Exchange (ETDEWEB)

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

    1958-07-01

    Collection of bibliographical references on plutonium and its principal compounds from 1942 to end of 1957. (author) [French] Compilation de references bibliographiques sur le plutonium et ses principaux composes de 1942 a fin 1957. (auteur)

  14. Observations sur la maturité sexuelle et la ponte du tourteau Cancer pagurus en Manche

    OpenAIRE

    Latrouite, Daniel; Noel, Philippe

    1993-01-01

    Peu d'observations sur le cycle reproducteur et la taille de maturité fonctionnelle du crabe tourteau en Manche ont été rapportées jusqu'à présent, probablement en raison de la non vulnérabilité des femelles ovigères. La présente étude repose sur les observations faites, trois années consécutivement, sur des femelles pêchées avant la période de ponte et placées dans des viviers en laboratoire. Après discussion sur les critères pertinents pour l'établissement de la taille moyenne de première m...

  15. Nuclear reactors and fuel cycle

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2014-07-01

    The Nuclear Fuel Center (CCN) of IPEN produces nuclear fuel for the continuous operation of the IEA-R1 research reactor of IPEN. The serial production started in 1988, when the first nuclear fuel element was delivered for IEA-R1. In 2011, CCN proudly presents the 100{sup th} nuclear fuel element produced. Besides routine production, development of new technologies is also a permanent concern at CCN. In 2005, U{sub 3}O{sub 8} were replaced by U{sub 3}Si{sub 2}-based fuels, and the research of U Mo is currently under investigation. Additionally, the Brazilian Multipurpose Research Reactor (RMB), whose project will rely on the CCN for supplying fuel and uranium targets. Evolving from an annual production from 10 to 70 nuclear fuel elements, plus a thousand uranium targets, is a huge and challenging task. To accomplish it, a new and modern Nuclear Fuel Factory is being concluded, and it will provide not only structure for scaling up, but also a safer and greener production. The Nuclear Engineering Center has shown, along several years, expertise in the field of nuclear, energy systems and correlated areas. Due to the experience obtained during decades in research and technological development at Brazilian Nuclear Program, personnel has been trained and started to actively participate in design of the main system that will compose the Brazilian Multipurpose Reactor (RMB) which will make Brazil self-sufficient in production of radiopharmaceuticals. The institution has participated in the monitoring and technical support concerning the safety, licensing and modernization of the research reactors IPEN/MB-01 and IEA-R1. Along the last two decades, numerous specialized services of engineering for the Brazilian nuclear power plants Angra 1 and Angra 2 have been carried out. The contribution in service, research, training, and teaching in addition to the development of many related technologies applied to nuclear engineering and correlated areas enable the institution to

  16. Opinion of the IRSN on the instruction on the continuation of the GPR assessment of the safety re-examination VD3-900 - Examination of the conclusive report of the safety re-examination of the nr 1 reactor of the Fessenheim plant after the third decennial inspection; Avis de l'IRSN sur l'instruction des suites du GPR bilan du reexamen de surete VD3-900 - Examen du rapport de conclusions du reexamen de surete du reacteur n.1 du CNPE de Fessenheim a l'issue de sa troisieme visite decennale

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2011-02-15

    This report first describes the context of the safety re-examination of the nr 1 reactor of the Fessenheim nuclear power station (CNPE) and assesses the generic aspects of this re-examination, assesses additional information transmitted by EDF and concerning these generic aspects (external and internal stresses, accidents and their radiological consequences, design of systems and civil engineering works), states recommendations on various topics and issues to be considered (internal explosions, probabilistic studies, severe accidents, confinement in post-accidental situation, behaviour of containment enclosures, and son on). It assesses the content of the conclusive report of the safety re-examination

  17. Quelques considérations sur la grippe aviaire

    Directory of Open Access Journals (Sweden)

    Michel Maffesoli

    2006-06-01

    Full Text Available Dans le totalitarisme doux étendant son voile sirupeux sur des masses inquiètes, l’on sait que les divers technocrates assoient leur pouvoir en entretenant la crainte. Ce qui n’est pas très compliqué, tant la peur de l’ombre, la peur de son ombre travaille tout un chacun. Si l’on doit caractériser l’époque, c’est bien le terme de lâcheté généralisée qui vient, immédiatement, à l’esprit. L’on sait que le virus de la grippe aviaire ne peut infecter l’homme que par contact direct et prolongé. Par exemple, boire l’eau d’un marais infecté de fiente d’oiseaux contaminés ou forniquer avec une poule atteinte de ce mal. De même, le danger de pandémie ne pourrait advenir que s’il y avait conjonction avec la grippe humaine. Ainsi, les virologues considèrent qu’il faudrait plusieurs centaines de personnes infectées par la grippe aviaire, dans un milieu lui-même en pleine épidémie de grippe humaine pour qu’il y ait un danger réel d’infection généralisée. Comme on le voit le risque est grand! Mais là n’est pas le problème. Il suffit, pour nos technocrates, que l’imaginaire de l’insécurité soit là. Ils y trouvent une raison d’être. Ils peuvent, savamment, jouer les utilités. On sait que de tous temps, c’est en misant sur une angoisse diffuse que les divers pouvoirs ont assis leur légitimité. En fait ce qui est à prendre au sérieux, ce sont les hystéries collectives. La chute spectaculaire de la consommation de volailles de toutes sortes en témoigne. Souvenons-nous aussi que n’est pas loin le temps où la même suspicion planait sur la viande bovine! Trêve de plaisanterie! Actualisons l’apologue. Ainsi l’émotion provoquée par le «double scandale» qui frapperait le C.N.R.S ne manque pas de susciter inquiétudes et interrogations. En terme d’épidémiologie bien entendu. Inquiétudes quant à la santé mentale du «milieu» sociologique capable de pétionner en m

  18. Heterogeneous Recycling in Fast Reactors

    Energy Technology Data Exchange (ETDEWEB)

    Forget, Benoit; Pope, Michael; Piet, Steven J.; Driscoll, Michael

    2012-07-30

    Current sodium fast reactor (SFR) designs have avoided the use of depleted uranium blankets over concerns of creating weapons grade plutonium. While reducing proliferation risks, this restrains the reactor design space considerably. This project will analyze various blanket and transmutation target configurations that could broaden the design space while still addressing the non-proliferation issues. The blanket designs will be assessed based on the transmutation efficiency of key minor actinide (MA) isotopes and also on mitigation of associated proliferation risks. This study will also evaluate SFR core performance under different scenarios in which depleted uranium blankets are modified to include minor actinides with or without moderators (e.g. BeO, MgO, B4C, and hydrides). This will be done in an effort to increase the sustainability of the reactor and increase its power density while still offering a proliferation resistant design with the capability of burning MA waste produced from light water reactors (LWRs). Researchers will also analyze the use of recycled (as opposed to depleted) uranium in the blankets. The various designs will compare MA transmutation efficiency, plutonium breeding characteristics, proliferation risk, shutdown margins and reactivity coefficients with a current reference sodium fast reactor design employing homogeneous recycling. The team will also evaluate the out-of-core accumulation and/or burn-down rates of MAs and plutonium isotopes on a cycle-by-cycle basis. This cycle-by-cycle information will be produced in a format readily usable by the fuel cycle systems analysis code, VISION, for assessment of the sustainability of the deployment scenarios.

  19. Modelisations des effets de surface sur les jets horizontaux subsoniques d'hydrogene et de methane

    Science.gov (United States)

    Gomez, Luis Fernando

    Le developpement des codes et de normes bases sur une methodologie scientifique requiert la capacite de predire l'etendue inflammable de deversements gazeux d'hydrogene sous differentes conditions. Des etudes anterieures ont deja etabli des modeles bases sur les lois de conservation de la mecanique des fluides basees sur des correlations experimentales qui permettent de predire la decroissance de la concentration et de la vitesse d'un gaz le long de l'axe d'un jet libre vertical. Cette etude s'interesse aux effets de proximite a une surface horizontale parallele sur un jet turbulent. Nous nous interessons a son impact sur l'etendue du champ de la concentration et sur l'enveloppe inflammable en particulier. Cette etude est comparative : l'hydrogene est compare au methane. Ceci permet de degager l'influence des effets de difference de la densite sur le comportement du jet, et de comparer le comportement de l'hydrogene aux correlations experimentales, qui ont ete essentiellement etablies pour le methane. Un modele decrivant l'evolution spatio-temporelle du champ de concentration du gaz dilue est propose, base sur la mecanique des fluides computationnelle. Cette approche permet de varier systematiquement les conditions aux frontieres (proximite du jet a la surface, par exemple) et de connaitre en detail les proprietes de l'ecoulement. Le modele est implemente dans le code de simulations par volumes finis de FLUENT. Les resultats des simulations sont compares avec les lois de similitudes decoulant de la theorie des jets d'ecoulements turbulents libres ainsi qu'avec les resultats experimentaux disponibles. L'effet de la difference des masses molaires des constituantes du jet et des constituantes du milieu de dispersion est egalement etudie dans le contexte du comportement d'echelle de la region developpee du jet.

  20. A new MTR fuel for a new MTR reactor: UMo for the Jules Horowitz reactor

    Energy Technology Data Exchange (ETDEWEB)

    Guigon, B. [CEA Cadarache, F-13108 Saint Paul lez Durance (France); Vacelet, H. [CERCA, Romans (France); Dornbusch, D. [Technicatome, Aix en Provence (France)

    2000-07-01

    Within some years, the Jules Horowitz Reactor will be the only working experimental reactor (material and fuel testing reactor) in France. It will have to provide facilities for a wide range of needs from activation analysis to power reactor fuel qualification. In this paper the main characteristics of the Jules Horowitz Reactor are presented. Safety criteria are explained. Finally, merits and disadvantages of UMo compared to the standard U{sub 3}Si{sub 2} fuel are discussed. (author)

  1. Propuesta de sistema de derivación regional de pacientes:una oportunidad para la cooperación sur-sur

    OpenAIRE

    Ortega, José Emilio; Espósito, Santiago Martín

    2014-01-01

    Teniendo en cuenta la problemática que muchas veces genera el acceso al sistema público de salud por parte de inmigrantes que carecen de políticas de desarrollo asistencial adecuadas, es necesario, teniendo en cuenta las implicancias del derecho a la salud y de la calidad de vida, generar un sistema regional de derivación de pacientes, el cual, financiado por un fondo dentro del marco de la cooperación sur-sur, permita financiar la atención médica y generar un recupero del gasto.

  2. Hacia una Psicología Social Comunitaria del Sur

    Directory of Open Access Journals (Sweden)

    German Rozas

    2015-11-01

    Full Text Available Este artículo tiene como objetivo proponer algunos caminos hacia un ámbito que hemos llamado simbólicamente una “Psicología Social Comunitaria del Sur”, es decir una disciplina que deje atrás los planteamientos venidos desde los países desarrollados, dado que alojan principalmente una mirada eurocéntrica. La referencia del Sur, es una propuesta metafórica, que no tiene un asidero geográfico, sino que apela a un otro, los del Sur, que significan la relación entre países de una manera diferente, incorporando a todos aquellas poblaciones, países, comunidades, independientes de su ubicación en el globo, que no se sienten incluidos en la categoría de países industrializados, modernos, autodenominados del norte. Desde la visibilización en América Latina de movimientos sociales asociados a comunidades indígenas, afrodescendientes y otras, la disciplina debiera reconfigurarse cualitativamente de modo que dé cuenta de estas nuevas realidades. Por un lado, algunas propuestas señalan acentuar la definición del concepto de comunidad desde una óptica más relacional. Es decir, entender comunidad como una matriz de cosmovisiones de mundo, la cual se articula con otras comunidades en una determinación mutua. Por otro lado, la intervención comunitaria ya debiera dejar atrás la solución de problemas que promuevan el progreso y el bienestar occidental, sino dirigirse más bien a trabajar la subjetividad, en el sentido de deconstruir la colonización del saber, para luego fortalecer la interpretación que hace cada comunidad desde su propia particularidad y cosmovisión situada. Finalmente, otra línea a sugerir es poner énfasis en un tipo de transformación social dirigida a la construcción de otra epistemología, que incorpore la interculturalidad, la plurinacionalidad, los derechos colectivos y por último una temática hoy día presente y en debate, el buen vivir.

  3. Simulation of power excursions - Osiris reactor; Simulation des excursions de puissance - pile Osiris

    Energy Technology Data Exchange (ETDEWEB)

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

    1964-07-01

    Following the experimental work accomplished in the U.S.A. on Borax 1 and SPERT 1 and the accident of SL 1, the 'Commissariat a l'Energie Atomique' started a research program about the safety of its own swimming Pool reactors, with regard to power excursions. The first research work led to the design of programmed explosive charges, adapted to the simulation of a power excursion. This report describes the application of these methods to the investigation of Osiris safety. (author) [French] A la suite des essais effectues aux U.S.A. sur BORAX 1 et SPERT 1 et de l'accident survenu a SL 1, le Commissariat a l'Energie Atomique a lance un programme d'etudes sur la surete de ses reacteurs piscines vis-a-vis des excursions de puissance. Les premieres etudes ont abouti A la mise au point de charges programmees capables de simuler une excursion de puissance. On trouvera dans le present rapport l'application de ces methodes a l'etude de la surete d'OSIRIS. (auteur)

  4. Neutrino Mixing Discriminates Geo-reactor Models

    CERN Document Server

    Dye, S T

    2009-01-01

    Geo-reactor models suggest the existence of natural nuclear reactors at different deep-earth locations with loosely defined output power. Reactor fission products undergo beta decay with the emission of electron antineutrinos, which routinely escape the earth. Neutrino mixing distorts the energy spectrum of the electron antineutrinos. Characteristics of the distorted spectrum observed at the earth's surface could specify the location of a geo-reactor, discriminating the models and facilitating more precise power measurement. The existence of a geo-reactor with known position could enable a precision measurement of the neutrino oscillation parameter delta-mass-squared.

  5. Reactor monitoring and safeguards using antineutrino detectors

    CERN Document Server

    Bowden, N S

    2008-01-01

    Nuclear reactors have served as the antineutrino source for many fundamental physics experiments. The techniques developed by these experiments make it possible to use these very weakly interacting particles for a practical purpose. The large flux of antineutrinos that leaves a reactor carries information about two quantities of interest for safeguards: the reactor power and fissile inventory. Measurements made with antineutrino detectors could therefore offer an alternative means for verifying the power history and fissile inventory of a reactors, as part of International Atomic Energy Agency (IAEA) and other reactor safeguards regimes. Several efforts to develop this monitoring technique are underway across the globe.

  6. Reactor assessments of advanced bumpy torus configurations

    Energy Technology Data Exchange (ETDEWEB)

    Uckan, N.A.; Owen, L.W.; Spong, D.A.; Miller, R.L.; Ard, W.B.; Pipkins, J.F.; Schmitt, R.J.

    1983-01-01

    Recently, several configurational approaches and concept improvement schemes were introduced for enhancing the performance of the basic ELMO Bumpy Torus (EBT) concept and for improving its reactor potential. These configurations include planar racetrack and square geometries, Andreoletti coil systems, and bumpy torus-stellarator hybrids (which include twisted racetrack and helical axis stellarator-snakey torus). Preliminary evaluations of reactor implications of each of these configurations have been carried out based on magnetics (vacuum) calculations, transport and scaling relationships, and stability properties. Results indicate favorable reactor projections with a significant reduction in reactor physical size as compared to conventional EBT reactor designs carried out in the past.

  7. Detection of antineutrinos for reactor monitoring

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Yeong Duk [Center for Underground Physics, Institute of Basic Science, Daejeon (Korea, Republic of)

    2016-04-15

    Reactor neutrinos have been detected in the past 50 years by various detectors for different purposes. Beginning in the 1980s, neutrino physicists have tried to use neutrinos to monitor reactors and develop an optimized detector for nuclear safeguards. Recently, motivated by neutrino oscillation physics, the technology and scale of reactor neutrino detection have progressed considerably. In this review, I will give an overview of the detection technology for reactor neutrinos, and describe the issues related to further improvements in optimized detectors for reactor monitoring.

  8. CFD Simulation on Ethylene Furnace Reactor Tubes

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Different mathematical models for ethylene furnace reactor tubes were reviewed. On the basis of these models a new mathematical simulation approach for reactor tubes based on computational fluid dynamics (CFD) technique was presented. This approach took the flow, heat transfer, mass transfer and thermal cracking reactions in the reactor tubes into consideration. The coupled reactor model was solved with the SIMPLE algorithm. Some detailed information about the flow field, temperature field and concentration distribution in the reactor tubes was obtained, revealing the basic characteristics of the hydrodynamic phenomena and reaction behavior in the reactor tubes. The CFD approach provides the necessary information for conclusive decisions regarding the production optimization, the design and improvement of reactor tubes, and the new techniques implementation.

  9. Advanced reactor physics methods for heterogeneous reactor cores

    Science.gov (United States)

    Thompson, Steven A.

    To maintain the economic viability of nuclear power the industry has begun to emphasize maximizing the efficiency and output of existing nuclear power plants by using longer fuel cycles, stretch power uprates, shorter outage lengths, mixed-oxide (MOX) fuel and more aggressive operating strategies. In order to accommodate these changes, while still satisfying the peaking factor and power envelope requirements necessary to maintain safe operation, more complexity in commercial core designs have been implemented, such as an increase in the number of sub-batches and an increase in the use of both discrete and integral burnable poisons. A consequence of the increased complexity of core designs, as well as the use of MOX fuel, is an increase in the neutronic heterogeneity of the core. Such heterogeneous cores introduce challenges for the current methods that are used for reactor analysis. New methods must be developed to address these deficiencies while still maintaining the computational efficiency of existing reactor analysis methods. In this thesis, advanced core design methodologies are developed to be able to adequately analyze the highly heterogeneous core designs which are currently in use in commercial power reactors. These methodological improvements are being pursued with the goal of not sacrificing the computational efficiency which core designers require. More specifically, the PSU nodal code NEM is being updated to include an SP3 solution option, an advanced transverse leakage option, and a semi-analytical NEM solution option.

  10. Reactor pulse repeatability studies at the annular core research reactor

    Energy Technology Data Exchange (ETDEWEB)

    DePriest, K.R. [Applied Nuclear Technologies, Sandia National Laboratories, Mail Stop 1146, Post Office Box 5800, Albuquerque, NM 87185-1146 (United States); Trinh, T.Q. [Nuclear Facility Operations, Sandia National Laboratories, Mail Stop 0614, Post Office Box 5800, Albuquerque, NM 87185-1146 (United States); Luker, S. M. [Applied Nuclear Technologies, Sandia National Laboratories, Mail Stop 1146, Post Office Box 5800, Albuquerque, NM 87185-1146 (United States)

    2011-07-01

    The Annular Core Research Reactor (ACRR) at Sandia National Laboratories is a water-moderated pool-type reactor designed for testing many types of objects in the pulse and steady-state mode of operations. Personnel at Sandia began working to improve the repeatability of pulse operations for experimenters in the facility. The ACRR has a unique UO{sub 2}-BeO fuel that makes the task of producing repeatable pulses difficult with the current operating procedure. The ACRR produces a significant quantity of photoneutrons through the {sup 9}Be({gamma}, n){sup 8}Be reaction in the fuel elements. The photoneutrons are the result of the gammas produced during fission and in fission product decay, so their production is very much dependent on the reactor power history and changes throughout the day/week of experiments in the facility. Because the photoneutrons interfere with the delayed-critical measurements required for accurate pulse reactivity prediction, a new operating procedure was created. The photoneutron effects at delayed critical are minimized when using the modified procedure. In addition, the pulse element removal time is standardized for all pulse operations with the modified procedure, and this produces less variation in reactivity removal times. (authors)

  11. In-reactor performance of pressure tubes in CANDU reactors

    Science.gov (United States)

    Rodgers, D. K.; Coleman, C. E.; Griffiths, M.; Bickel, G. A.; Theaker, J. R.; Muir, I.; Bahurmuz, A. A.; Lawrence, S. St.; Resta Levi, M.

    2008-12-01

    The pressure tubes in CANDU reactors have been operating for times up to about 25 years. The in-reactor performance of Zr-2.5Nb pressure tubes has been evaluated by sampling and periodic inspection. This paper describes the behaviour and discusses the factors controlling the behaviour of these components in currently operating CANDU reactors. The mechanical properties (such as ultimate tensile strength, UTS, and fracture toughness), and delayed-hydride-cracking properties (crack growth rate Vc, and threshold stress intensity factor, KIH) change with irradiation; the former reach a limiting value at a fluence of Pressure tubes exhibit elongation and diametral expansion. The deformation behaviour is a function of operating conditions and material properties that vary from tube-to-tube and as a function of axial location. Semi-empirical predictive models have been developed to describe the deformation response of average tubes as a function of operating conditions. For corrosion and, more importantly deuterium pickup, semi-empirical predictive models have also been developed to represent the behaviour of an average tube. The effect of material variability on corrosion behaviour is less well defined compared with other properties. Improvements in manufacturing have increased fracture resistance by minimising trace elements, especially H and Cl, and reduced variability by tightening controls on forming parameters, especially hot-working temperatures.

  12. Contaminantes en los cuerpos de agua del sur de Sonora

    Directory of Open Access Journals (Sweden)

    López-Ríos Olga

    2001-01-01

    Full Text Available Objetivo. Ahondar en el conocimiento sobre la incidencia de las actividades productivas del hombre en su medio, y el riesgo potencial que representa el deterioro ambiental para su propia salud y la sobrevivencia de especies animales. Material y métodos. Se utilizó el paquete informático Decision Support System for Industrial Pollution Control DSS (IPC, desarrollado por el Banco Mundial, la Organización Panamericana de la Salud (OPS y la Organización Mundial de la Salud (OMS, que se aplicó a un estudio de caso sobre los cuerpos de agua del sur de Sonora, durante 1996. Resultados. Estos sugieren que existen al menos tres factores que han contribuido a la desaparición de criaderos naturales de pescado y camarón en el municipio de Huatabampo: a la filtración de fertilizantes y pesticidas en las aguas de los drenes; b el asolvamiento producido por el depósito continuo, en el pasado, de agua de cola de la industria, c y la descarga inapropiada de aguas negras en los drenes. El texto completo en inglés de este artículo está disponible en: http://www.insp.mx/salud/index.html

  13. de La Ciénega, costa sur de Jalisco

    Directory of Open Access Journals (Sweden)

    Peter R. W. Gerritsen

    2008-01-01

    Full Text Available Hoy día la producción agroindustrial de alimentos es una actividad que está causando gran impacto tanto en los recursos naturales como en las culturas y los tejidos sociales; mientras que el modo campesino, opuesto al agroindustrial, propone una agricultura justa con base en las prácticas y experiencias campesinas generando así alternativas sustentables de producción.En este artículo se analizan cuatro estudios de caso de agricultores en el ejido de La Ciénega en la costa sur de Jalisco, los cuales se ubican en estos dos sistemas de producción. Los resultados exponen las técnicas de producción y estrategias campesinas que se desarrollan, así como la relación de los sistemas de producción ante las políticas agropecuarias. Terminamos resaltando la importancia de las prácticas y experiencias endógenas para el fortalecimiento de un desarrollo rural sustentable

  14. Pensando en el sur. El Llano en el siglo XVII

    Directory of Open Access Journals (Sweden)

    lzard, Miquel

    1994-06-01

    Full Text Available Not available.

    La agresión occidental a la futura Venezuela supuso, entre otras muchas cosas, que quienes la rechazaron, africanos que no querían ser esclavos, nativos huyendo del acoso o blancos refractarios, organizaran una sociedad cimarrona en el Llano. Cuadrúpedos huidos también del norte incrementaron la oferta de herbívoros cazables e implicaron, con los equinos, mayor autonomía y capacidad defensiva. También pensaron en el sur, por motivos antagónicos, quienes descendieron a capturar indígenas para venderlos como esclavos y quienes vieron en los orejanos la posibilidad de organizar una ganadería excedentaria. Estos últimos, miembros de la oligarquía, resolvieron que debían ocupar las sabanas por tres razones: aumentar su control sobre los pastos, liquidar competidores y extirpar un muy mal ejemplo, el de las personas libres de la cimarronera. El conflicto que a finales del siglo XVIII devendría fatal, en las dos acepciones de la palabra, se fraguó ya a mediados del siglo XVII.

  15. Uruguay: el sur también existe

    Directory of Open Access Journals (Sweden)

    Carmen Morente Muñoz

    2013-06-01

    Full Text Available La República Oriental del Uruguay resulta un país bastante desconocido. Creador del primer “Estado del Bienestar”, a principios del siglo XX, sus particularidades no lo hacen tan distinto al resto de países de América Latina. Padeció la dictadura más cruenta del Cono Sur y las inclemencias de las políticas neoliberales. En 2004, el Frente Amplio, conquista la mayoría parlamentaria y el gobierno, abriendo un camino de esperanzas y de reconstrucción económica y social. A través de sus políticas públicas, ahora desarrolladas por el segundo gobierno de la izquierda (2010, hace frente a la realidad heredada: más de un tercio de su población había sido condenada a la pobreza. Palabras-clave: Uruguay, dictadura, impunidad, derechos humanos.

  16. Cultura cabocla en el sur de Brasil un abordaje preliminar

    Directory of Open Access Journals (Sweden)

    Pedro Martins

    2003-12-01

    Full Text Available This text is a research report concerning the cabocla (mestizo population of southern Brazil, focusing on cultural aspects, seen here as a distinguishing system. This population is studied in terms of the migratory process that begins with their expulsion from the countryside, their adaptation to the small towns, passing through the periphery of the large cities and finally returning to the countryside. The article attempts to understand their musical practices, the technology that they have appropriated and their religiosity, all of which have been, symbolically and materially, reconstructed in their complexity.//Este texto es un reporte de la investigación sobre la población cabocla en el sur de Brasil, centrado en los aspectos culturales vistos como un sistema distintivo. Esta población es estudiada en los términos de un proceso migratorio que empieza con su expulsión del campo, su adaptación a pueblos pequeños, pasando por la periferia de las grandes ciudades y finalmente, retornando al campo. El artículo busca entender las prácticas musicales, la tecnología que apropiaron y sus prácticas religiosas, aspectos todos que han sido simbólica y materialmente reconstruidos en su complejidad.

  17. Periodismo ambiental en Canal Sur Televisión

    Directory of Open Access Journals (Sweden)

    Lic. Miguel Montaño Montaño

    1999-01-01

    Full Text Available El autor estudia el origen histórico del periodismo ambiental, la evolución en España y Andalucía y su aparición en Canal Sur TV Realiza un análisis sobre la información medioambiental, especialidad del periodismo que en la década de los noventa despierta nuevamente gran interés entre el público. La televisión autonómica ha dedicado, desde su creación numerosos programas sobre el medio ambiente. Actualmente sus Servicios Informativos tienen la sección Medio Ambiente. De la importancia que se concede a este tipo de información es un buen ejemplo el programa «Tierra y Mar», que incorpora progresivamente noticias medioambientales, referidas a la educación ambiental, el mantenimiento y recuperación de la biodiversidad y la presentación de modelos de conducta respetuosos.

  18. Reactor G1: high power experiments; Experiences a forte puissance

    Energy Technology Data Exchange (ETDEWEB)

    Laage, F. de; Teste du Baillet, A.; Veyssiere, A.; Wanner, G. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires; Retel, H. [Societe Rateau, D.E.A. (France)

    1957-07-01

    The experiments carried out in the starting-up programme of the reactor G1 comprised a series of tests at high power, which allowed the following points to be studied: 1- Effect of poisoning by Xenon (absolute value, evolution). 2- Temperature coefficients of the uranium and graphite for a temperature distribution corresponding to heating by fission. 3- Effect of the pressure (due to the coiling system) on the reactivity. 4- Calibration of the security rods as a function of their position in the pile (1). 5- Temperature distribution of the graphite, the sheathing, the uranium and the air leaving the canals, in a pile running normally at high power. 6- Neutron flux distribution in a pile running normally at high power. 7- Determination of the power by nuclear and thermodynamic methods. These experiments have been carried out under two very different pile conditions. From the 1. to the 15. of August 1956, a series of power increases, followed by periods of stabilisation, were induced in a pile containing uranium only, in 457 canals, amounting to about 34 tons of fuel. A knowledge of the efficiency of the control rods in such a pile has made it possible to measure with good accuracy the principal effects at high temperatures, that is, to deal with points 1, 2, 3, 5. Flux charts giving information on the variations of the material Laplacian and extrapolation lengths in the reflector have been drawn up. Finally the thermodynamic power has been measured under good conditions, in spite of some installation difficulties. On September 16, the pile had its final charge of 100 tons. All the canals were loaded, 1,234 with uranium and 53 (i.e. exactly 4 per cent of the total number) with thorium uniformly distributed in a square lattice of 100 cm side. Since technical difficulties prevented the calibration of the control rods, the measurements were limited to the determination of the thermodynamic power and the temperature distributions (points 5 and 7). This report will

  19. Fluidized bed coal combustion reactor

    Science.gov (United States)

    Moynihan, P. I.; Young, D. L. (Inventor)

    1981-01-01

    A fluidized bed coal reactor includes a combination nozzle-injector ash-removal unit formed by a grid of closely spaced open channels, each containing a worm screw conveyor, which function as continuous ash removal troughs. A pressurized air-coal mixture is introduced below the unit and is injected through the elongated nozzles formed by the spaces between the channels. The ash build-up in the troughs protects the worm screw conveyors as does the cooling action of the injected mixture. The ash layer and the pressure from the injectors support a fluidized flame combustion zone above the grid which heats water in boiler tubes disposed within and/or above the combustion zone and/or within the walls of the reactor.

  20. Nuclear reactor alignment plate configuration

    Energy Technology Data Exchange (ETDEWEB)

    Altman, David A; Forsyth, David R; Smith, Richard E; Singleton, Norman R

    2014-01-28

    An alignment plate that is attached to a core barrel of a pressurized water reactor and fits within slots within a top plate of a lower core shroud and upper core plate to maintain lateral alignment of the reactor internals. The alignment plate is connected to the core barrel through two vertically-spaced dowel pins that extend from the outside surface of the core barrel through a reinforcement pad and into corresponding holes in the alignment plate. Additionally, threaded fasteners are inserted around the perimeter of the reinforcement pad and into the alignment plate to further secure the alignment plate to the core barrel. A fillet weld also is deposited around the perimeter of the reinforcement pad. To accomodate thermal growth between the alignment plate and the core barrel, a gap is left above, below and at both sides of one of the dowel pins in the alignment plate holes through with the dowel pins pass.

  1. Transport simulation for EBT reactor

    Energy Technology Data Exchange (ETDEWEB)

    Uckan, T.; Uckan, N.A.; Jaeger, E.F.

    1983-08-01

    Transport simulation and modeling studies for the ELMO Bumpy Torus (EBT) reactor are carried out by using zero-dimensional (0-D) and one-and-one-half-dimensional (1 1/2-D) transport calculations. The time-dependent 0-D model is used for global analysis, whereas the 1 1/2-D radial transport code is used for accurate determination of density, temperature, and ambipolar potential profiles and of the role of these profiles in reactor plasma performance. Analysis with the 1 1/2-D transport code shows that profile effects near the outer edge of the hot electron ring lead to enhanced confinement by at least a factor of 2 to 5 beyond the simple scaling that is obtained from the global analysis. The radial profiles of core plasma density and temperatures (or core pressure) obtained from 1 1/2-D transport calculations are found to be similar to those theoretically required for stability.

  2. Gas-liquid autoxidation reactors

    Energy Technology Data Exchange (ETDEWEB)

    Morbidelli, M.; Paludetto, R.; Carra, S.

    1986-01-01

    A procedure for the simulation of autoxidation gas-liquid reactors has been developed based both on mathematical models and laboratory experiments. It has been shown that the complex radical chain mechanism of the autoxidation process can be simulated through two global parallel reactions, whose rates are obtained by assuming pseudo-steady-state concentration values for all the radical species involved. Using ethylbenzene autoxidation as a model reaction, an experimental analysis has been performed in order to estimate all the kinetic parameters of the model. The effect of the interaction between gas-liquid mass-transfer phenomena and the complex kinetic mechanism on the overall performance of an autoxidation reactor has been examined in detail within the framework of the liquid film model.

  3. Fast breeder reactor protection system

    Science.gov (United States)

    van Erp, J.B.

    1973-10-01

    Reactor protection is provided for a liquid-metal-fast breeder reactor core by measuring the coolant outflow temperature from each of the subassemblies of the core. The outputs of the temperature sensors from a subassembly region of the core containing a plurality of subassemblies are combined in a logic circuit which develops a scram alarm if a predetermined number of the sensors indicate an over temperature condition. The coolant outflow from a single subassembly can be mixed with the coolant outflow from adjacent subassemblies prior to the temperature sensing to increase the sensitivity of the protection system to a single subassembly failure. Coherence between the sensors can be required to discriminate against noise signals. (Official Gazette)

  4. Reactor vessel lower head integrity

    Energy Technology Data Exchange (ETDEWEB)

    Rubin, A.M.

    1997-02-01

    On March 28, 1979, the Three Mile Island Unit 2 (TMI-2) nuclear power plant underwent a prolonged small break loss-of-coolant accident that resulted in severe damage to the reactor core. Post-accident examinations of the TMI-2 reactor core and lower plenum found that approximately 19,000 kg (19 metric tons) of molten material had relocated onto the lower head of the reactor vessel. Results of the OECD TMI-2 Vessel Investigation Project concluded that a localized hot spot of approximately 1 meter diameter had existed on the lower head. The maximum temperature on the inner surface of the reactor pressure vessel (RPV) in this region reached 1100{degrees}C and remained at that temperature for approximately 30 minutes before cooling occurred. Even under the combined loads of high temperature and high primary system pressure, the TMI-2 RPV did not fail. (i.e. The pressure varied from about 8.5 to 15 MPa during the four-hour period following the relocation of melt to the lower plenum.) Analyses of RPV failure under these conditions, using state-of-the-art computer codes, predicted that the RPV should have failed via local or global creep rupture. However, the vessel did not fail; and it has been hypothesized that rapid cooling of the debris and the vessel wall by water that was present in the lower plenum played an important role in maintaining RPV integrity during the accident. Although the exact mechanism(s) of how such cooling occurs is not known, it has been speculated that cooling in a small gap between the RPV wall and the crust, and/or in cracks within the debris itself, could result in sufficient cooling to maintain RPV integrity. Experimental data are needed to provide the basis to better understand these phenomena and improve models of RPV failure in severe accident codes.

  5. Faits saillants de l'Enquete canadienne sur les capacites financieres de 2009 dans le domaine de la retraite

    OpenAIRE

    Schellenberg, Grant; Ostrovsky, Yuri

    2010-01-01

    L'Enquete canadienne sur les capacites financieres (ECCF), dont les donnees ont ete diffusees par Statistique Canada en decembre 2009, a ete concue pour recueillir de l'information concernant les connaissances, les capacites et les comportements des Canadiens en ce qui a trait a la prise de decisions financieres. Outre les donnees sur les approches de gestion de l'argent et de planification financiere, l'ECCF a recueilli des donnees sur des questions pertinentes dans le contexte des discussio...

  6. The ARIES tokamak reactor study

    Energy Technology Data Exchange (ETDEWEB)

    1989-10-01

    The ARIES study is a community effort to develop several visions of tokamaks as fusion power reactors. The aims are to determine the potential economics, safety, and environmental features of a range of possible tokamak reactors, and to identify physics and technology areas with the highest leverage for achieving the best tokamak reactor. Three ARIES visions are planned, each having a different degree of extrapolation from the present data base in physics and technology. The ARIES-I design assumes a minimum extrapolation from current tokamak physics (e.g., 1st stability) and incorporates technological advances that can be available in the next 20 to 30 years. ARIES-II is a DT-burning tokamak which would operate at a higher beta in the 2nd MHD stability regime. It employs both potential advances in the physics and expected advances in technology and engineering. ARIES-II will examine the potential of the tokamak and the D{sup 3}He fuel cycle. This report is a collection of 14 papers on the results of the ARIES study which were presented at the IEEE 13th Symposium on Fusion Engineering (October 2-6, 1989, Knoxville, TN). This collection describes the ARIES research effort, with emphasis on the ARIES-I design, summarizing the major results, the key technical issues, and the central conclusions.

  7. Actinide transmutation in nuclear reactors

    Energy Technology Data Exchange (ETDEWEB)

    Bultman, J.H.

    1995-01-17

    An optimization method is developed to maximize the burning capability of the ALMR while complying with all constraints imposed on the design for reliability and safety. This method leads to a maximal transuranics enrichment, which is being limited by constraints on reactivity. The enrichment can be raised by using the neutrons less efficiently by increasing leakage from the fuel. With the developed optimization method, a metallic and an oxide fueled ALMR were optimized. Both reactors perform equally well considering the burning of transuranics. However, metallic fuel has a much higher heat conductivity coefficient, which in general leads to better safety characteristics. In search of a more effective waste transmuter, a modified Molten Salt Reactor was designed. A MSR operates on a liquid fuel salt which makes continuous refueling possible, eliminating the issue of the burnup reactivity loss. Also, a prompt negative reactivity feedback is possible for an overmoderated reactor design, even when the Doppler coefficient is positive, due to the fuel expansion with fuel temperature increase. Furthermore, the molten salt fuel can be reprocessed based on a reduction process which is not sensitive to the short-lived spontaneously fissioning actinides. (orig./HP).

  8. Assessment of the thorium fuel cycle in power reactors

    Energy Technology Data Exchange (ETDEWEB)

    Kasten, P.R.; Homan, F.J.; Allen, E.J.

    1977-01-01

    A study was conducted at Oak Ridge National Laboratory to evaluate the role of thorium fuel cycles in power reactors. Three thermal reactor systems were considered: Light Water Reactors (LWRs); High-Temperature Gas-Cooled Reactors (HTGRs); and Heavy Water Reactors (HWRs) of the Canadian Deuterium Uranium Reactor (CANDU) type; most of the effort was on these systems. A summary comparing thorium and uranium fuel cycles in Fast Breeder Reactors (FBRs) was also compiled.

  9. Investigation of molten salt fast reactor

    Energy Technology Data Exchange (ETDEWEB)

    Kubota, Kenichi; Konomura, Mamoru [Japan Nuclear Cycle Development Inst., Tokai, Ibaraki (Japan)

    2002-05-01

    On survey research for practicability strategy of fast reactor (FR) (phase 1), to extract future practicability image candidates of FR from wide options, in addition to their survey and investigation objects of not only solid fuel reactors of conventional research object but also molten salt reactor as a flowing fuel reactor, investigation on concept of molten salt FR plant was carried out. As a part of the first step of the survey research for practicability strategy, a basic concept on plant centered at nuclear reactor facility using chloride molten salt reactor capable of carrying out U-Pu cycle was examined, to perform a base construction to evaluate economical potential for a practical FBR. As a result, a result could be obtained that because of inferior fuel inventory and heat transmission to those in Na cooling reactor in present knowledge, mass of reactor vessel and intermediate heat exchanger were to widely increased to expect reduction of power generation unit price even on considering cheapness of its fuel cycle cost. Therefore, at present step further investigation on concept design of the chloride molten salt reactor plant system is too early in time, and it is at a condition where basic and elementary researches aiming at upgrading of economical efficiency such as wide reduction of fuel inventory, a measure expectable for remarkable rationalization effect of reprocessing system integrating a reactor to a processing facility, and so on. (G.K.)

  10. Pouvoir et sexualité. Le discours féministe sur la prostitution en France (1968-1986.

    Directory of Open Access Journals (Sweden)

    Damien Simonin

    2010-07-01

    Full Text Available Cette recherche porte sur les discours sur la prostitution dans la presse féministe, entre 1968 et 1986 en France. Durant cette période, le mouvement féministe est composé de courants conflictuels (courants réformistes et révolutionnaires, différentialistes et universalistes et il porte des discours hétérogènes (informations sur la prostitution, analyses théoriques et politiques, témoignages de prostituées. Pourtant, ces discours s'accordent sur la revendication d'une libération des rapport...

  11. Impact d'Internet sur la suicidalité. À propos d'une " googling study " sur la rétro-information médiatique d'un pacte suicidaire échafaudé sur le Web

    OpenAIRE

    Auxéméry, Y.; Fidelle, G.

    2010-01-01

    Resume La communication via Internet ne cesse de se developper dans une societe de plus en plus mediatisee. A l?occasion d?un pacte suicidaire recemment conclu sur la toile, les medias se sont interroges sur la responsabilite du Web en tant que promoteur du suicide. Apres une revue de la litterature explorant les liens entre Internet et suicidalite, nous evoquerons les determinants epidemiologiques et psychopathologiques du pacte suicidaire elabore sur Internet ou cybersuicide. Nou...

  12. y el Mercado Común del Sur (MERCOSUR

    Directory of Open Access Journals (Sweden)

    Ángel Moros

    2006-01-01

    Full Text Available Se analizan algunos indicadores propuestos por la Cumbre Mundial sobre la Sociedad de la Información con el fin de comparar el desarrollo de las políticas nacionales de información, los niveles de tecnologización y la funcionalidad en los países que conforman los bloques de la Comunidad Andina de Naciones y El Mercado Común del Sur. El primer bloque está constituido por Bolivia, Colombia, Ecuador, Perú y Venezuela y el segundo está conformado por Argentina, Brasil, Paraguay, Uruguay y Venezuela, para los efectos de este artículo también se incluye a Chile. Este estudio se desarrolla bajo las características del paradigma tecnológico preparado por la División Desarrollo Productivo y Empresarial de la CEPAL que reconocen ocho fundamentos, de los cuales, para este trabajo se aplicaron dos, el primero enfoca la exogeneidad de las trayectorias tecnológicas, que por sus características se puede aplicar a gran parte de los países de la región, teniendo en cuenta que sus trayectorias son determinadas fuera de los sistemas de innovación La endogeneidad institucional, política y normativa, se inserta en la complejidad y en la incertidumbre de los sistemas de información, parte de modelos enfrentados a trayectorias tecnológicas exógenas, en los cuales los países tienen sus respectivos grados de libertad y varían según su nivel de desarrollo

  13. Molten-Salt Depleted-Uranium Reactor

    CERN Document Server

    Dong, Bao-Guo; Gu, Ji-Yuan

    2015-01-01

    The supercritical, reactor core melting and nuclear fuel leaking accidents have troubled fission reactors for decades, and greatly limit their extensive applications. Now these troubles are still open. Here we first show a possible perfect reactor, Molten-Salt Depleted-Uranium Reactor which is no above accident trouble. We found this reactor could be realized in practical applications in terms of all of the scientific principle, principle of operation, technology, and engineering. Our results demonstrate how these reactors can possess and realize extraordinary excellent characteristics, no prompt critical, long-term safe and stable operation with negative feedback, closed uranium-plutonium cycle chain within the vessel, normal operation only with depleted-uranium, and depleted-uranium high burnup in reality, to realize with fission nuclear energy sufficiently satisfying humanity long-term energy resource needs, as well as thoroughly solve the challenges of nuclear criticality safety, uranium resource insuffic...

  14. Performance of a multipurpose research electrochemical reactor

    Energy Technology Data Exchange (ETDEWEB)

    Henquin, E.R. [Programa de Electroquimica Aplicada e Ingenieria Electroquimica (PRELINE), Facultad de Ingenieria Quimica, Universidad Nacional del Litoral, Santiago del Estero 2829, S3000AOM Santa Fe (Argentina); Bisang, J.M., E-mail: jbisang@fiq.unl.edu.ar [Programa de Electroquimica Aplicada e Ingenieria Electroquimica (PRELINE), Facultad de Ingenieria Quimica, Universidad Nacional del Litoral, Santiago del Estero 2829, S3000AOM Santa Fe (Argentina)

    2011-07-01

    Highlights: > For this reactor configuration the current distribution is uniform. > For this reactor configuration with bipolar connection the leakage current is small. > The mass-transfer conditions are closely uniform along the electrode. > The fluidodynamic behaviour can be represented by the dispersion model. > This reactor represents a suitable device for laboratory trials. - Abstract: This paper reports on a multipurpose research electrochemical reactor with an innovative design feature, which is based on a filter press arrangement with inclined segmented electrodes and under a modular assembly. Under bipolar connection, the fraction of leakage current is lower than 4%, depending on the bipolar Wagner number, and the current distribution is closely uniform. When a turbulence promoter is used, the local mass-transfer coefficient shows a variation of {+-}10% with respect to its mean value. The fluidodynamics of the reactor responds to the dispersion model with a Peclet number higher than 10. It is concluded that this reactor is convenient for laboratory research.

  15. Sulfide toxicity kinetics of a uasb reactor

    Directory of Open Access Journals (Sweden)

    D. R. Paula Jr.

    2009-12-01

    Full Text Available The effect of sulfide toxicity on kinetic parameters of anaerobic organic matter removal in a UASB (up-flow anaerobic sludge blanket reactor is presented. Two lab-scale UASB reactors (10.5 L were operated continuously during 12 months. The reactors were fed with synthetic wastes prepared daily using glucose, ammonium acetate, methanol and nutrient solution. One of the reactors also received increasing concentrations of sodium sulfide. For both reactors, the flow rate of 16 L.d-1 was held constant throughout the experiment, corresponding to a hydraulic retention time of 15.6 hours. The classic model for non-competitive sulfide inhibition was applied to the experimental data for determining the overall kinetic parameter of specific substrate utilization (q and the sulfide inhibition coefficient (Ki. The application of the kinetic parameters determined allows prediction of methanogenesis inhibition and thus the adoption of operating parameters to minimize sulfide toxicity in UASB reactors.

  16. L'Explication Lexicologique Sur l'Expression Vivante des Jeux de Mots

    Institute of Scientific and Technical Information of China (English)

    丁树英

    2010-01-01

    @@ 0 Résumé Le jeu de mots est un phénomène très fréquent dans la vie courante.Nous le fréquentons partout, comme sur des journaux, sur des magazines ou sur des livres. Cénéralement, nous trouvons que c'est intéressant et nous prenons intér(e)t à la lecture des jeux de mots. Le présent article vise à faire un peu d'analyse sur ce phénomène du point de vue lexicale. Ⅱse divise en quatre parties : premièrement, c'est la relation étroite entre les jeux de mots et la lexicologie ; deuxièmement, c'est l'application de la lexicologie dans les jeux de mots, y compris plusieurs aspects ;troisièmement, c'est un peu de réflexion sur l'avantage et défaut des jeux de mots ; enfin, c'est la conclusion que la lexicologic joue un r?le très important en faisant des jeux de mots.

  17. Espacio herido, tiempo acelerado, imaginario conmovido. Interrogantes sobre la postmodernidad del Sur.

    Directory of Open Access Journals (Sweden)

    Mabel Franzone

    2010-11-01

    Full Text Available Estableciendo una relación estrecha entre espacio, tiempo e imaginario, este escrito intenta tratar la gran separación Norte- Sur, acaecida con la hipermodernidad y sus consecuencias sobre la destrucción del espacio del Sur ; la cuestión de fondo encara las huellas que puede dejar en los cuerpos y en los imaginarios. Los límites impuestos se tratan en cuatro niveles : históricos, geográficos, económicos- sociales y de la representación. Para una crítica de la modernidad se han tomado parámetros de pensamiento que operan en una trama mediana, forma de pensar propia al Sur y que muestran la necesidad de una epistemología también propia al Sur, que refleje las cuestiones fundamentales y que tenga en cuenta la emancipación y la solidaridad como categorías para repensar el Sur.

  18. Redox regulation of SurR by protein disulfide oxidoreductase in Thermococcus onnurineus NA1.

    Science.gov (United States)

    Lim, Jae Kyu; Jung, Hae-Chang; Kang, Sung Gyun; Lee, Hyun Sook

    2017-03-01

    Protein disulfide oxidoreductases are redox enzymes that catalyze thiol-disulfide exchange reactions. These enzymes include thioredoxins, glutaredoxins, protein disulfide isomerases, disulfide bond formation A (DsbA) proteins, and Pyrococcus furiosus protein disulfide oxidoreductase (PfPDO) homologues. In the genome of a hyperthermophilic archaeon, Thermococcus onnurineus NA1, the genes encoding one PfPDO homologue (TON_0319, Pdo) and three more thioredoxin- or glutaredoxin-like proteins (TON_0470, TON_0472, TON_0834) were identified. All except TON_0470 were recombinantly expressed and purified. Three purified proteins were reduced by a thioredoxin reductase (TrxR), indicating that each protein can form redox complex with TrxR. SurR, a transcription factor involved in the sulfur response, was tested for a protein target of a TrxR-redoxin system and only Pdo was identified to be capable of catalyzing the reduction of SurR. Electromobility shift assay demonstrated that SurR reduced by the TrxR-Pdo system could bind to the DNA probe with the SurR-binding motif, GTTttgAAC. In this study, we present the TrxR-Pdo couple as a redox-regulator for SurR in T. onnurineus NA1.

  19. Introduction to the neutron kinetics of nuclear power reactors

    CERN Document Server

    Tyror, J G; Grant, P J

    2013-01-01

    An Introduction to the Neutron Kinetics of Nuclear Power Reactors introduces the reader to the neutron kinetics of nuclear power reactors. Topics covered include the neutron physics of reactor kinetics, feedback effects, water-moderated reactors, fast reactors, and methods of plant control. The reactor transients following faults are also discussed, along with the use of computers in the study of power reactor kinetics. This book is comprised of eight chapters and begins with an overview of the reactor physics characteristics of a nuclear power reactor and their influence on system design and

  20. Microstructured reactors for hydrogen production

    Energy Technology Data Exchange (ETDEWEB)

    Aartun, Ingrid

    2005-07-01

    Small scale hydrogen production by partial oxidation (POX) and oxidative steam reforming (OSR) have been studied over Rh-impregnated microchannel Fecralloy reactors and alumina foams. Trying to establish whether metallic microchannel reactors have special advantages for hydrogen production via catalytic POX or OSR with respect to activity, selectivity and stability was of special interest. The microchannel Fecralloy reactors were oxidised at 1000 deg C to form a {alpha}-Al2O3 layer in the channels in order to enhance the surface area prior to impregnation. Kr-BET measurements showed that the specific surface area after oxidation was approximately 10 times higher than the calculated geometric surface area. Approximately 1 mg Rh was deposited in the channels by impregnation with an aqueous solution of RhCl3. Annular pieces (15 mm o.d.,4 mm i.d., 14 mm length) of extruded {alpha}-Al2O3 foams were impregnated with aqueous solutions of Rh(NO3)3 to obtain 0.01, 0.05 and 0.1 wt.% loadings, as predicted by solution uptake. ICP-AES analyses showed that the actual Rh loadings probably were higher, 0.025, 0.077 and 0.169 wt.% respectively. One of the microchannel Fecralloy reactors and all Al2O3 foams were equipped with a channel to allow for temperature measurement inside the catalytic system. Temperature profiles obtained along the reactor axes show that the metallic microchannel reactor is able to minimize temperature gradients as compared to the alumina foams. At sufficiently high furnace temperature, the gas phase in front of the Rh/Al2O3/Frecralloy microchannel reactor and the 0.025 wt.% Rh/Al2O3 foams ignites. Gas phase ignition leads to lower syngas selectivity and higher selectivity to total oxidation products and hydrocarbon by-products. Before ignition of the gas phase the hydrogen selectivity is increased in OSR as compared to POX, the main contribution being the water-gas shift reaction. After gas phase ignition, increased formation of hydrocarbon by

  1. Plasma spark discharge reactor and durable electrode

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Young I.; Cho, Daniel J.; Fridman, Alexander; Kim, Hyoungsup

    2017-01-10

    A plasma spark discharge reactor for treating water. The plasma spark discharge reactor comprises a HV electrode with a head and ground electrode that surrounds at least a portion of the HV electrode. A passage for gas may pass through the reactor to a location proximate to the head to provide controlled formation of gas bubbles in order to facilitate the plasma spark discharge in a liquid environment.

  2. Experimental Breeder Reactor I Preservation Plan

    Energy Technology Data Exchange (ETDEWEB)

    Julie Braun

    2006-10-01

    Experimental Breeder Reactor I (EBR I) is a National Historic Landmark located at the Idaho National Laboratory, a Department of Energy laboratory in southeastern Idaho. The facility is significant for its association and contributions to the development of nuclear reactor testing and development. This Plan includes a structural assessment of the interior and exterior of the EBR I Reactor Building from a preservation, rather than an engineering stand point and recommendations for maintenance to ensure its continued protection.

  3. Reactor Bolshoi Moshchnosti Kalani; Reacteurs RBMK

    Energy Technology Data Exchange (ETDEWEB)

    Bastien, D. [Conservatoire National des Arts et Metiers (CNAM), 75 - Paris (France)

    2000-01-01

    The Reactor Bolshoi Molshchnosti Kalani (RBMK) are pressure tubes reactor, boiling light water cooled. Exported since 1990 from the ex-USSR, they are today in three independent countries: Russian, Ukraine and Lithuania. Since this date, data exchange with the occident allowed the better knowledge of this reactor type. The design, the technical description (core, fuel, primary system), the safety and the improvement since Chernobyl are detailed. (A.L.B.)

  4. NASA Reactor Facility Hazards Summary. Volume 1

    Science.gov (United States)

    1959-01-01

    The Lewis Research Center of the National Aeronautics and Space Administration proposes to build a nuclear research reactor which will be located in the Plum Brook Ordnance Works near Sandusky, Ohio. The purpose of this report is to inform the Advisory Committee on Reactor Safeguards of the U. S. Atomic Energy Commission in regard to the design Lq of the reactor facility, the characteristics of the site, and the hazards of operation at this location. The purpose of this research reactor is to make pumped loop studies of aircraft reactor fuel elements and other reactor components, radiation effects studies on aircraft reactor materials and equipment, shielding studies, and nuclear and solid state physics experiments. The reactor is light water cooled and moderated of the MTR-type with a primary beryllium reflector and a secondary water reflector. The core initially will be a 3 by 9 array of MTR-type fuel elements and is designed for operation up to a power of 60 megawatts. The reactor facility is described in general terms. This is followed by a discussion of the nuclear characteristics and performance of the reactor. Then details of the reactor control system are discussed. A summary of the site characteristics is then presented followed by a discussion of the larger type of experiments which may eventually be operated in this facility. The considerations for normal operation are concluded with a proposed method of handling fuel elements and radioactive wastes. The potential hazards involved with failures or malfunctions of this facility are considered in some detail. These are examined first from the standpoint of preventing them or minimizing their effects and second from the standpoint of what effect they might have on the reactor facility staff and the surrounding population. The most essential feature of the design for location at the proposed site is containment of the maximum credible accident.

  5. Heat for industry from nuclear reactors

    Energy Technology Data Exchange (ETDEWEB)

    Kikoin, I.K.; Novikov, V.M.

    Two factors which incline nations toward the use of heat from nuclear reactors for industrial use are: 1) exhaustion of cheap fossil fuel resources, and 2) ecological problems associated both with extraction of fossil fuel from the earth and with its combustion. In addition to the usual problems that beset nuclear reactors, special problems associated with using heat from nuclear reactors in various industries are explored.

  6. D-D tokamak reactor studies

    Energy Technology Data Exchange (ETDEWEB)

    Evans, K.E. Jr.; Baker, C.C.; Brooks, J.N.; Ehst, D.A.; Finn, P.A.; Jung, J.; Mattas, R.F.; Misra, B.; Smith, D.L.; Stevens, H.C.

    1980-11-01

    A tokamak D-D reactor design, utilizing the advantages of a deuterium-fueled reactor but with parameters not unnecessarily extended from existing D-T designs, is presented. Studies leading to the choice of a design and initial studies of the design are described. The studies are in the areas of plasma engineering, first-wall/blanket/shield design, magnet design, and tritium/fuel/vacuum requirements. Conclusions concerning D-D tokamak reactors are stated.

  7. Recent developments concerning the fusion; Developpements recents sur la fusion

    Energy Technology Data Exchange (ETDEWEB)

    Jacquinot, J. [CEA/Cadarache, Dept. de Recherches sur la Fusion Controlee, DRFC, 13 - Saint Paul lez Durance (France); Andre, M. [CEA/DAM Ile de France, 91 - Bruyeres Le Chatel (France); Aymar, R. [ITER Joint Central Team Garching, Muenchen (Germany)] [and others

    2000-09-04

    Organized the 9 march 2000 by the SFEN, this meeting on the european program concerning the fusion, showed the utility of the exploitation and the enhancement of the actual technology (JET, Tore Supra, ASDEX) and the importance of the Europe engagement in the ITER program. The physical stakes for the magnetic fusion have been developed with a presentation of the progresses in the knowledge of the stability limits. A paper on the inertial fusion was based on the LMJ (Laser MegaJoule) project. The two blanket concepts chosen in the scope of the european program on the tritium blankets, have been discussed. These concepts will be validated by irradiation tests in the ITER-FEAT and adapted for a future reactor. (A.L.B.)

  8. Energy memento; Memento sur l'energie

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-07-01

    This memento about energy provides a series of tables with numerical data relative to energy resources and uses in France, in the European Union and in the rest of the world: energy consumption (primary energy, forecasting, CO{sub 2} emissions, energy independence, supplies, uses and imports, demand scenarios, energy savings..), power production (production, forecasting, loads, consumption, hydro-power, thermal equipment, exports), nuclear power (production, forecasting, reactors population, characteristics of French PWRs, uranium needs and fuel cycle), energy resources (renewable energies, fossil fuels and uranium reserves and production), economic data (gross national product, economic and energy indicators, prices and cost estimations), energy units and conversion factors (counting, calorific value of coals, production costs, energy units). (J.S.)

  9. Initiating Events for Multi-Reactor Plant Sites

    Energy Technology Data Exchange (ETDEWEB)

    Muhlheim, Michael David [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Flanagan, George F. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Poore, III, Willis P. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2014-09-01

    Inherent in the design of modular reactors is the increased likelihood of events that initiate at a single reactor affecting another reactor. Because of the increased level of interactions between reactors, it is apparent that the Probabilistic Risk Assessments (PRAs) for modular reactor designs need to specifically address the increased interactions and dependencies.

  10. High Performance Photocatalytic Oxidation Reactor System Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Pioneer Astronautics proposes a technology program for the development of an innovative photocatalytic oxidation reactor for the removal and mineralization of...

  11. Savannah River Site reactor safety assessment. Draft

    Energy Technology Data Exchange (ETDEWEB)

    Woody, N.D.; Brandyberry, M.D. [eds.] [Westinghouse Savannah River Co., Aiken, SC (United States); Baker, W.H.; Brandyberry, M.D.; Kearnaghan, D.P.; O`Kula, K.R.; Woody, N.D. [Westinghouse Savannah River Co., Aiken, SC (United States); Amos, C.N.; Weingardt, J.J. [Science Applications International Corp., San Diego, CA (United States)

    1991-02-28

    This report gives the results of a Savannah River Site (SRS) Production Reactor risk assessment. Measures of adverse consequences to health and safety resulting from representations of severe accidents in SRS reactors are presented. In addition, the report gives a summary of the methods employed to represent these accidents and to assess the resultant consequences. The report is issued to provide timely information to the US Department of Energy (DOE) on the risk of operation of SRS reactors, for insights into severe accident phenomena that contribute to this risk, and in support of improved bases for other Site programs in Heavy Water Reactor safety.

  12. History of fast reactor fuel development

    Energy Technology Data Exchange (ETDEWEB)

    Kittel, J.H.; Frost, B.R.T. (Argonne National Lab., IL (United States)); Mustelier, J.P. (COGEMA, Velizy-Villacoublay (France))

    1992-01-01

    Most of the first generation of fast reactors that were operated at significant power levels employed solid metal fuels. They were constructed in the United States and United Kingdom in the 1950s and included Experimental Breeder Reactor (EBR)-I and -II operated by Argonne National Laboratory, United States, the Enrico Fermi Reactor operated by the Atomic Power Development Associates, United States and DFR operated by the U.K. Atomic Energy Authority (UKAEA). Their paper tracer pre-development of fast reactor fuel from these early days through the 1980s including ceramic fuels.

  13. Advanced nuclear reactor types and technologies

    Energy Technology Data Exchange (ETDEWEB)

    Ignatiev, V. [ed.; Feinberg, O.; Morozov, A. [Russian Research Centre `Kurchatov Institute`, Moscow (Russian Federation); Devell, L. [Studsvik Eco and Safety AB, Nykoeping (Sweden)

    1995-07-01

    The document is a comprehensive world-wide catalogue of concepts and designs of advanced fission reactor types and fuel cycle technologies. Two parts have been prepared: Part 1 Reactors for Power Production and Part 2 Heating and Other Reactor Applications. Part 3, which will cover advanced waste management technology, reprocessing and disposal for different nuclear fission options is planned for compilation during 1995. The catalogue was prepared according to a special format which briefly presents the project title, technical approach, development status, application of the technology, reactor type, power output, and organization which developed these designs. Part 1 and 2 cover water cooled reactors, liquid metal fast reactors, gas-cooled reactors and molten salt reactors. Subcritical accelerator-driven systems are also considered. Various reactor applications as power production, heat generation, ship propulsion, space power sources and transmutation of such waste are included. Each project is described within a few pages with the main features of an actual design using a table with main technical data and figure as well as references for additional information. Each chapter starts with an introduction which briefly describes main trends and approaches in this field. Explanations of terms and abbreviations are provided in a glossary.

  14. Supercritical-pressure light water cooled reactors

    CERN Document Server

    Oka, Yoshiaki

    2014-01-01

    This book focuses on the latest reactor concepts, single pass core and experimental findings in thermal hydraulics, materials, corrosion, and water chemistry. It highlights research on supercritical-pressure light water cooled reactors (SCWRs), one of the Generation IV reactors that are studied around the world. This book includes cladding material development and experimental findings on heat transfer, corrosion and water chemistry. The work presented here will help readers to understand the fundamental elements of reactor design and analysis methods, thermal hydraulics, materials and water

  15. Sandia National Laboratories Medical Isotope Reactor concept.

    Energy Technology Data Exchange (ETDEWEB)

    Coats, Richard Lee; Dahl, James J.; Parma, Edward J., Jr.

    2010-04-01

    This report describes the Sandia National Laboratories Medical Isotope Reactor and hot cell facility concepts. The reactor proposed is designed to be capable of producing 100% of the U.S. demand for the medical isotope {sup 99}Mo. The concept is novel in that the fuel for the reactor and the targets for the {sup 99}Mo production are the same. There is no driver core required. The fuel pins that are in the reactor core are processed on a 7 to 21 day irradiation cycle. The fuel is low enriched uranium oxide enriched to less than 20% {sup 235}U. The fuel pins are approximately 1 cm in diameter and 30 to 40 cm in height, clad with Zircaloy (zirconium alloy). Approximately 90 to 150 fuel pins are arranged in the core in a water pool {approx}30 ft deep. The reactor power level is 1 to 2 MW. The reactor concept is a simple design that is passively safe and maintains negative reactivity coefficients. The total radionuclide inventory in the reactor core is minimized since the fuel/target pins are removed and processed after 7 to 21 days. The fuel fabrication, reactor design and operation, and {sup 99}Mo production processing use well-developed technologies that minimize the technological and licensing risks. There are no impediments that prevent this type of reactor, along with its collocated hot cell facility, from being designed, fabricated, and licensed today.

  16. NCSU reactor sharing program. Final technical report

    Energy Technology Data Exchange (ETDEWEB)

    Perez, P.B.

    1997-01-10

    The Nuclear Reactor Program at North Carolina State University provides the PULSTAR Research Reactor and associated facilities to eligible institutions with support, in part, from the Department of Energy Reactor Sharing Program. Participation in the NCSU Reactor Sharing Program continues to increase steadily with visitors ranging from advance high school physics and chemistry students to Ph.D. level research from neighboring universities. This report is the Final Technical Report for the DOE award reference number DE-FG05-95NE38136 which covers the period September 30, 1995 through September 30, 1996.

  17. Molecular ecology of anaerobic reactor systems

    DEFF Research Database (Denmark)

    Hofman-Bang, H. Jacob Peider; Zheng, D.; Westermann, Peter;

    2003-01-01

    Anaerobic reactor systems are essential for the treatment of solid and liquid wastes and constitute a core facility in many waste treatment plants. Although much is known about the basic metabolism in different types of anaerobic reactors, little is known about the microbes responsible...... to the abundance of each microbe in anaerobic reactor systems by rRNA probing. This chapter focuses on various molecular techniques employed and problems encountered when elucidating the microbial ecology of anaerobic reactor systems. Methods such as quantitative dot blot/fluorescence in-situ probing using various...

  18. Advances in light water reactor technologies

    CERN Document Server

    Saito, Takehiko; Ishiwatari, Yuki; Oka, Yoshiaki

    2010-01-01

    ""Advances in Light Water Reactor Technologies"" focuses on the design and analysis of advanced nuclear power reactors. This volume provides readers with thorough descriptions of the general characteristics of various advanced light water reactors currently being developed worldwide. Safety, design, development and maintenance of these reactors is the main focus, with key technologies like full MOX core design, next-generation digital I&C systems and seismic design and evaluation described at length. This book is ideal for researchers and engineers working in nuclear power that are interested

  19. Nanostructured Catalytic Reactors for Air Purification Project

    Data.gov (United States)

    National Aeronautics and Space Administration — This SBIR Phase I project proposes the development of lightweight compact nanostructured catalytic reactors for air purification from toxic gaseous organic...

  20. Phosphorus removal in aerated stirred tank reactor

    Energy Technology Data Exchange (ETDEWEB)

    Ghigliazza, R.; Lodi, A.; Rovatti, M. [Inst. of Chemical and Process Engineering ``G.B. Bonino``, Univ. of Genoa (Italy)

    1999-03-01

    The possibility to obtain biological phosphorus removal in strictly aerobic conditions has been investigated. Experiments, carried out in a continuous stirred tank reactor (CSTR), show the feasibility to obtain phosphorus removal without the anaerobic phase. Reactor performance in terms of phosphorus abatement kept always higher then 65% depending on adopted sludge retention time (SRT). In fact increasing SRT from 5 days to 8 days phosphorus removal and reactor performance increase but overcoming this SRT value a decreasing in reactor efficiency was recorded. (orig.) With 6 figs., 3 tabs., 18 refs.

  1. Sodium fast reactors with closed fuel cycle

    CERN Document Server

    Raj, Baldev; Vasudeva Rao, PR 0

    2015-01-01

    Sodium Fast Reactors with Closed Fuel Cycle delivers a detailed discussion of an important technology that is being harnessed for commercial energy production in many parts of the world. Presenting the state of the art of sodium-cooled fast reactors with closed fuel cycles, this book:Offers in-depth coverage of reactor physics, materials, design, safety analysis, validations, engineering, construction, and commissioning aspectsFeatures a special chapter on allied sciences to highlight advanced reactor core materials, specialized manufacturing technologies, chemical sensors, in-service inspecti

  2. Autonomous Control of Space Nuclear Reactors Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Nuclear reactors to support future robotic and manned missions impose new and innovative technological requirements for their control and protection instrumentation....

  3. Neutron imaging on the VR-1 reactor

    Science.gov (United States)

    Crha, J.; Sklenka, L.; Soltes, J.

    2016-09-01

    Training reactor VR-1 is a low power research reactor with maximal thermal power of 1 kW. The reactor is operated by the Faculty of Nuclear Science and Physical Engineering of the Czech Technical University in Prague. Due to its low power it suits as a tool for education of university students and training of professionals. In 2015, as part of student research project, neutron imaging was introduced as another type of reactor utilization. The low available neutron flux and the limiting spatial and construction capabilities of the reactor's radial channel led to the development of a special filter/collimator insertion inside the channel and choosing a nonstandard approach by placing a neutron imaging plate inside the channel. The paper describes preliminary experiments carried out on the VR-1 reactor which led to first radiographic images. It seems, that due to the reactor construction and low reactor power, the neutron imaging technique on the VR-1 reactor is feasible mainly for demonstration or educational and training purposes.

  4. Microchannel Methanation Reactors Using Nanofabricated Catalysts Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Makel Engineering, Inc. (MEI) and the Pennsylvania State University (Penn State) propose to develop and demonstrate a microchannel methanation reactor based on...

  5. Nanostructured Catalytic Reactors for Air Purification Project

    Data.gov (United States)

    National Aeronautics and Space Administration — This SBIR Phase II project proposes the development of lightweight compact nanostructured catalytic reactors for air purification from toxic gaseous organic...

  6. Continuous steroid biotransformations in microchannel reactors.

    Science.gov (United States)

    Marques, Marco P C; Fernandes, Pedro; Cabral, Joaquim M S; Znidaršič-Plazl, Polona; Plazl, Igor

    2012-01-15

    The use of microchannel reactor based technologies within the scope of bioprocesses as process intensification and production platforms is gaining momentum. Such trend can be ascribed a particular set of characteristics of microchannel reactors, namely the enhanced mass and heat transfer, combined with easier handling and smaller volumes required, as compared to traditional reactors. In the present work, a continuous production process of 4-cholesten-3-one by the enzymatic oxidation of cholesterol without the formation of any by-product was assessed. The production was carried out within Y-shaped microchannel reactors in an aqueous-organic two-phase system. Substrate was delivered from the organic phase to aqueous phase containing cholesterol oxidase and the product formed partitions back to the organic phase. The aqueous phase was then forced through a plug-flow reactor, containing immobilized catalase. This step aimed at the reduction of hydrogen peroxide formed as a by-product during cholesterol oxidation, to avoid cholesterol oxidase deactivation due to said by-product. This setup was compared with traditional reactors and modes of operation. The results showed that microchannel reactor geometry outperformed traditional stirred tank and plug-flow reactors reaching similar conversion yields at reduced residence time. Coupling the plug-flow reactor containing catalase enabled aqueous phase reuse with maintenance of 30% catalytic activity of cholesterol oxidase while eliminating hydrogen peroxide. A final production of 36 m of cholestenone was reached after 300 hours of operation.

  7. Quelques noddees sur l’ecologie de la vedetation des dunes et sur la fonction de l’enraciment dans l’edification de dunes a la Cote Mediterraneenne de la France. I

    NARCIS (Netherlands)

    Boterenbrood, A.J.; Donsellaar-Ten Bokkel Huinink, van W.A.E.; Donselaar, van J.

    1956-01-01

    Dans la végétation des dunes du Languedoc J. BRAUN-BLANQUET (1952) distingue trois associations, à savoir; 1) l’Agropyretum mediterraneum parmi et sur les premières dunes basses; 2) l’Ammophiletum arundinaceae sur les dunes plus hautes; et 3) le Crucianelletum maritimae dans les dépressions et en ar

  8. Reactors for nuclear electric propulsion

    Energy Technology Data Exchange (ETDEWEB)

    Buden, D.; Angelo, J.A. Jr.

    1981-01-01

    Propulsion is the key to space exploitation and power is the key to propulsion. This paper examines the role of nuclear fission reactors as the primary power source for high specific impulse electric propulsion systems for space missions of the 1980s and 1990s. Particular mission applications include transfer to and a reusable orbital transfer vehicle from low-Earth orbit to geosynchronous orbit, outer planet exploration and reconnaissance missions, and as a versatile space tug supporting lunar resource development. Nuclear electric propulsion is examined as an indispensable component in space activities of the next two decades.

  9. Biodegradation of MTBE in reactors

    DEFF Research Database (Denmark)

    Waul, Christopher Kevin

    2007-01-01

    The fuel oxygenate methyl tert-butyl ether (MTBE) was first introduced in the 1970’s to improve gasoline combustion efficiency and reduce emission of harmful gases. However, it has caused groundwater contamination in Denmark and in many locations worldwide through accidental releases from leaking...... such as ammonium or benzene, toluene, ethyl benzene and xylene (BTEX) oxidizers, which can be present together in a single system. The competition resulted in reduced and/or delayed degradation of MTBE when there were limitations of oxygen or space in the reactor. The fraction of biologically active (BA) MTBE...

  10. Les recherches des hispanistes sur les médias (1985-1996

    Directory of Open Access Journals (Sweden)

    Jean-Michel Desvois

    2007-05-01

    Full Text Available De 1986 à 1996, période pour laquelle nous avons effectué ce bilan, un intérêt croissant s'est manifesté pour la recherche sur les médias et notamment sur la presse. Un noyau dur d'une vingtaine de chercheurs a produit avec régularité ouvrages et articles sur ces domaines en les considérant à part entière, mais bien d'autres les ont abordés de façon oblique et ont ainsi contribué à une production scientifique qui représente près de trois cents références, dont plus de vingt thèses.Malgré l'ab...

  11. Quels impacts des TIC sur le développement durable ?

    Directory of Open Access Journals (Sweden)

    Benoît Dumolin

    2015-07-01

    Full Text Available La première partie de l’étude examine quels sont les impacts des TIC sur le développement durable. A l’inverse d’une approche sectorielle, l’objectif du développement durable s’inscrit à l’intersection des sphères sociétale, économique, environnementale et de la gouvernance. La dimension transversale des TIC rend l’analyse des interactions entre ces quatre piliers difficile d’autant plus que l’influence du numérique sur l’économie ou sur l’organisation sociale est complexe à mesurer. Les effe...

  12. Impact du stress hydrique sur le fonctionnement hydraulique foliaire du peuplier Populus tremula x alba

    OpenAIRE

    Daaboul, Philippe

    2015-01-01

    Afin d’aborder l’impact du stress hydrique sur le fonctionnement hydraulique foliaire, des plants de Populus tremula x alba ont été soumis à un stress hydrique modéré ou sévère pendant une semaine par ajout de PEG dans la solution nutritive. La mesure de paramètres écophysiologiques et moléculaires tissus spécifiques a permis de dégager plusieurs tendances sur la caractérisation de l’influence du stress. Les deux types de stress n’ont que peu d’impact sur la croissance et la capacité de synth...

  13. Urbanismo y arquitectura moderna en madera en el sur de Chile: 1930-1970

    Directory of Open Access Journals (Sweden)

    Gonzalo Cerda Brintrup

    2015-04-01

    Full Text Available La investigación que se presenta tiene como objetivos estudiar el desarrollo de la arquitectura moderna en madera en el sur de Chile; indagar acerca de como esta se incerta en la tradición maderera de la arquitectura del sur; investigar su relación con el desarrollo de una identidad arquitectónica local;localizar y analizar sus ejemplos más significativos. El área de estudio es desde la VIII hasta la X Región, específicamente desde la Provincia de Concepción hasta Chiloé, por cuanto allí se concentra la mayor parte de la arquitectura en madera del sur del país.

  14. Les images amateur sur Citizenside. Entre encadrement et uniformisation

    Directory of Open Access Journals (Sweden)

    Aurélie Aubert

    2014-04-01

    Full Text Available L’émergence de l’utilisation des images amateur au sein des médias modifie-t-elle les formes dominantes ou privilégiées de l’information d’actualité ? Cet article est une monographie sur le site Citizenside qui commercialise auprès de médias nationaux et internationaux des photographies prises par des photographes non titulaires d’une carte de presse. Cette entreprise exerce une activité d’encadrement et de validation des contenus présentés comme « amateur », qui contribue à les légitimer mais aussi à les uniformiser. D’un point de vue méthodologique, nous avons réalisé une enquête quantitative à partir d’un classement typologique opéré sur 221 événements couverts par les utilisateurs du site ainsi que des entretiens semi-directifs auprès de huit acteurs du processus de circulation des images. Cet article examine tout d’abord l’évolution des représentations de l’actualité saisies par des amateurs dans des conditions particulières de production. Il semble que les visuels reflètent une actualité programmée et circonscrite dans l’espace (France et Europe. On note en effet, la faible variété d’évènements captés et la domination d’un point de vue « occidentalo-centré ». Nous abordons ensuite, dans une démarche sociologique d’étude des métiers et des pratiques professionnelles, les normes journalistiques entrant en jeu dans le travail de sélection des faits et d’éditorialisation mené par la rédaction et, ce faisant, analysons la diversification des activités journalistiques. Il apparaît, après observation des trajectoires des documents sur Citizenside, que les conditions de leur circulation sont toujours sous l’emprise des professionnels. Ces derniers « travaillent » les images, leur ajoutent un cadre et cherchent à signer toujours davantage leur appartenance au monde de l’information. Dans le même temps, le caractère « non professionnel » de ces

  15. Revenir vers les habitants, revenir sur les territoires

    Directory of Open Access Journals (Sweden)

    Élizabeth Auclair

    2011-05-01

    Full Text Available Le développement durable se voulait un projet de civilisation, mais le concept a vite été fragilisé par la suprématie des intérêts économiques, et par l’enfermement dans des préoccupations d’ordre environnemental. Dans la période de crise actuelle, on s’interroge : comment veut-on vivre ? avec quelles valeurs ? dans quelles villes et dans quels territoires? Il s’agit ici de voir comment les arts et la culture peuvent contribuer à cet objectif du « vivre ensemble ». Au-delà de positionnements opportunistes, on observe qu’une meilleure prise en compte de la culture, dans ses différentes acceptions, peut promouvoir des approches transversales, reposant sur les valeurs de solidarité, de respect de la diversité culturelle, de démocratie locale et de citoyenneté, et remettre ainsi les habitants au cœur des politiques et des projets de territoires. La recomposition du paysage culturel que l’on observe en France, notamment autour des agendas 21 de la culture et des nouveaux territoires de l’art, témoigne de la part d’artistes, élus et autres professionnels de la culture d’une volonté de travailler au plus près de la population afin de monter des projets qui remettent la culture au cœur des politiques locales.Sustainable development was supposed to be a “civilization” concept, but the power of the economic interests and the pressure of the environmental issues have fragilized the concept. With the recent world crisis, many questions now arise: we must change our model, but how do we want to live, with which values and indicators, in what kind of towns and territories? In this article we propose to analyse how cultural development can help to reach the aim of “living together”. Indeed, taking into account cultural diversity and initiating local activities enables to develop new kinds of projects with the inhabitants, and to promote essential values such as local democracy, solidarity, tolerance

  16. El volcanismo del Terciario superior del sur de Mendoza

    Directory of Open Access Journals (Sweden)

    F. E. Nullo

    2002-06-01

    Full Text Available Se describe por primera vez la petrografía y geoquímica de unidades volcánicas terciarias del sur de la provincia de Mendoza. Se analizan la nomenclatura estratigráfica y sus edades, estableciéndose una secuencia de eventos magmáticos ocurridos durante el Neógeno, comenzando con la evolución de un retro-arco, seguido por un arco magmático más joven. Se intenta respetar la nomenclatura estratigráfica existente, sin embargo, la definición de unidades se ha realizado sobre la base de las edades radimétricas y sus edades de cristalización, más sobre sus características petrográficas. La actividad magmática se extiende desde el Oligoceno superior al Mioceno superior, correspondiendo a el Ciclo Eruptivo Molle y el Ciclo Eruptivo Huincán, y comenzó con un episodio magmático basáltico inicial (CEM. Esta actividad se generó en la corteza inferior dominada por la concentración de gabros, dioritas y rocas híbridas (granulitas máficas. Debido a un engrosamiento de la corteza como consecuencia de la actividad tectónica durante Mioceno superior o por el estancamiento de magmas o por la combinación de ambos procesos, la formación de granulitas granatíferas resultó un producto distintivo de la corteza inferior. Con el desarrollo del arco magmático (CEH en el Mioceno superior, los magmas ascendieron desde la fuente mantélica, encontrándose con una corteza inferior granatífera, perdiendo capacidad de ascenso por falta de contraste de densidades, produciéndose una fusión extendida, la homogeinización y el ascenso, en equilibrio con la corteza baja, proceso que caracteriza el volcanismo de un arco magmático.

  17. REGLES DE RECHERCE D\\'INFORMATION SUR L\\'INTERNET: SIMULATION AGENTS INTELLIGENTS

    Directory of Open Access Journals (Sweden)

    Dorin Militaru

    2007-10-01

    Full Text Available Les agents de recherche disponibles sur l’Internet sont des outils permettant aux consommateurs de comparer les prix d’un produit proposé par différents vendeurs. Les agents existants basent leur recherche sur une liste prédéfinie de vendeurs ŕ consulter, autrement dit, ils utilisent une rčgle de recherche avec une taille d’échantillon fixe (agent de recherche FSS. Toutefois, dans le futur, avec la mise en place de nouveaux systčmes de tarification des communications sur le réseau, cette rčgle de recherche est susceptible d’évoluer vers d’autres rčgles plus flexibles permettrant aux agents de faire un arbitrage entre les coűts de communication et le prix trouvé. Dans ce cadre, la rčgle de recherche séquentielle optimale (agent de recherche RP est une alternative possible. Néanmoins, son adoption va dépendre fortement de ses performances espérées. Dans cet article, nous analysons les performances relatives d’agents RP et FSS sur un marché oů l’accčs ŕ l’information est coűteux. A l’équilibre théorique du marché, nous montrons que les agents de recherche RP permettent toujours aux consommateurs de payer des coűts totaux moins élevés. Dans un second temps, nous testons la robustesse de ce résultat théorique en simulant un marché sur lequel les agents de recherche RP et les vendeurs n’ont qu’une information partielle sur sa structure.

  18. Mild hypoxia in vivo regulates cardioprotective SUR2A: A role for Akt and LDH.

    Science.gov (United States)

    Mohammed Abdul, Khaja Shameem; Jovanović, Sofija; Du, Qingyou; Sukhodub, Andriy; Jovanović, Aleksandar

    2015-05-01

    High-altitude residents have lower mortality rates for ischaemic heart disease and this is ascribed to cardiac gene remodelling by chronic hypoxia. SUR2A is a cardioprotective ABC protein serving as a subunit of sarcolemmal ATP-sensitive K(+) channels. The purpose of this study was to determine whether SUR2A is regulated by mild hypoxia in vivo and to elucidate the underlying mechanism. Mice were exposed to either 21% (control) or 18% (mild hypoxia) oxygen for 24h. Exposure to 18% oxygen did not affect partial pressure of O(2) (PO(2)) and CO(2) (PCO(2)) in the blood, haematocrit or level of ATP in the heart. However, hypoxia increased myocardial lactate dehydrogenase (LDH) and lactate as well as NAD(+) without affecting total NAD. SUR2A levels were significantly increased as well as myocardial resistance to ischaemia-reperfusion. Exposure to 18% oxygen did not phosphorylate extracellular signal regulated kinases (ERK1/2) or AMP activated protein kinase (AMPK), but it phosphorylated protein kinase B (Akt). An inhibitor of phosphoinositide 3-kinases (PI3K), LY294002 (0.2mg/mouse), abolished all observed effects of hypoxia. LDH inhibitors, galloflavin (50 μM) and sodium oxamate (80 mM) significantly decreased levels of SUR2A in heart embryonic H9c2 cells, while inactive mutant LDH form, gly193-M-LDH increased cellular sensitivity towards stress induced by 2,4-dinitrophenol (10mM). Treatment of H9c2 cells with sodium lactate (30 mM) increased intracellular lactate, but did not affect LDH activity or SUR2A levels. We conclude that PI3K/Akt signalling pathway and LDH play a crucial role in increase of cardiac SUR2A induced by in vivo exposure to 18% oxygen.

  19. Los primeros grupos humanos depredadores en el sur de la Peninsula (Andalucía, Murcia, Albacete.

    Directory of Open Access Journals (Sweden)

    Ricardo Montes Bernardez

    1992-01-01

    Full Text Available En este trabajo se traza una revisión y una síntesis general sobre el estado de la investigación acerca del Paleolítico Inferior en el Sur de la Península Ibérica : Andalucía, Murcia y Sur de Albacete.

  20. Coupled reactor kinetics and heat transfer model for heat pipe cooled reactors

    Science.gov (United States)

    Wright, Steven A.; Houts, Michael

    2001-02-01

    Heat pipes are often proposed as cooling system components for small fission reactors. SAFE-300 and STAR-C are two reactor concepts that use heat pipes as an integral part of the cooling system. Heat pipes have been used in reactors to cool components within radiation tests (Deverall, 1973); however, no reactor has been built or tested that uses heat pipes solely as the primary cooling system. Heat pipe cooled reactors will likely require the development of a test reactor to determine the main differences in operational behavior from forced cooled reactors. The purpose of this paper is to describe the results of a systems code capable of modeling the coupling between the reactor kinetics and heat pipe controlled heat transport. Heat transport in heat pipe reactors is complex and highly system dependent. Nevertheless, in general terms it relies on heat flowing from the fuel pins through the heat pipe, to the heat exchanger, and then ultimately into the power conversion system and heat sink. A system model is described that is capable of modeling coupled reactor kinetics phenomena, heat transfer dynamics within the fuel pins, and the transient behavior of heat pipes (including the melting of the working fluid). This paper focuses primarily on the coupling effects caused by reactor feedback and compares the observations with forced cooled reactors. A number of reactor startup transients have been modeled, and issues such as power peaking, and power-to-flow mismatches, and loading transients were examined, including the possibility of heat flow from the heat exchanger back into the reactor. This system model is envisioned as a tool to be used for screening various heat pipe cooled reactor concepts, for designing and developing test facility requirements, for use in safety evaluations, and for developing test criteria for in-pile and out-of-pile test facilities. .

  1. UNASUR Salud: un nueva diplomacia en salud en América del Sur?

    OpenAIRE

    Herrero,María Belén

    2014-01-01

    Desde la creación de Unión de Naciones Suramericanas (UNASUR), las políticas de salud devinieron en un factor estratégico en América del Sur con la intención de revertir el enfoque de ajuste que reinaba como resultado del auge del neoliberalismo a fines del siglo pasado. El ascenso al poder de gobiernos de tendencia izquierdista en América del Sur trajo una nueva actitud hacia el orden internacional y la reforma interna social al mismo tiempo que se creó un nuevo consenso sobre gobernanza reg...

  2. Espacio herido, tiempo acelerado, imaginario conmovido. Interrogantes sobre la postmodernidad del Sur.

    OpenAIRE

    Mabel Franzone

    2010-01-01

    Estableciendo una relación estrecha entre espacio, tiempo e imaginario, este escrito intenta tratar la gran separación Norte- Sur, acaecida con la hipermodernidad y sus consecuencias sobre la destrucción del espacio del Sur ; la cuestión de fondo encara las huellas que puede dejar en los cuerpos y en los imaginarios. Los límites impuestos se tratan en cuatro niveles : históricos, geográficos, económicos- sociales y de la representación. Para una crítica de la modernidad se han tomado parámetr...

  3. Informations sur le projet Changement d’ Utilisation et de Couverture des Sols

    Directory of Open Access Journals (Sweden)

    Alain Podaire

    2000-05-01

    Full Text Available La communauté travaillant sur les changements de l’environnement global accorde une importance croissante aux modifications d’occupation et d’utilisation des sols et la nécessité d’une approche multidisciplinaire de ce sujet. En effet, ces changements ont un impact significatif sur les intéractions surface terrestre - atmosphère (biogéochimie, chimie de l’atmosphère, eau et énergie, la biodiversité (structure et fonctionnement des écosystèmes, diversité des espèces, fragmentation de la couv...

  4. Compound cryopump for fusion reactors

    CERN Document Server

    Kovari, M; Shephard, T

    2013-01-01

    We reconsider an old idea: a three-stage compound cryopump for use in fusion reactors such as DEMO. The helium "ash" is adsorbed on a 4.5 K charcoal-coated surface, while deuterium and tritium are adsorbed at 15-22 K on a second charcoal-coated surface. The helium is released by raising the first surface to ~30 K. In a separate regeneration step, deuterium and tritium are released at ~110 K. In this way, the helium can be pre-separated from other species. In the simplest design, all three stages are in the same vessel, with a single valve to close the pump off from the tokamak during regeneration. In an alternative design, the three stages are in separate vessels, connected by valves, allowing the stages to regenerate without interfering with each other. The inclusion of the intermediate stage would not affect the overall pumping speed significantly. The downstream exhaust processing system could be scaled down, as much of the deuterium and tritium could be returned directly to the reactor. This could reduce ...

  5. K-East and K-West Reactors

    Data.gov (United States)

    Federal Laboratory Consortium — Hanford's "sister reactors", the K-East and the K-West Reactors, were built side-by-side in the early 1950's. The two reactors went operational within four months of...

  6. Impact des aménagements sur la migration anadrome du saumon atlantique (Salmo salar L. sur le gave de Pau (France

    Directory of Open Access Journals (Sweden)

    CHANSEAU M.

    1999-04-01

    Full Text Available Le suivi par radiotélémétrie de la migration anadrome de 114 saumons atlantiques sur le Gave de Pau, réalisé de 1995 à 1997, a permis d'étudier l'impact de 31 des 37 obstacles érigés sur l'axe de migration. Cinq obstacles majeurs ont été identifiés en regard de leur faible perméabilité et/ou des retards qu'ils induisent ainsi que de leur position sur l'axe. La transparence de ces 5 aménagements permettrait à plus de 80 % (contre seulement 13 % dans la situation actuelle des saumons de parvenir sur de bonnes zones de frayères. L'accumulation des retards au niveau de chaque obstacle peut empêcher une proportion non négligeable des poissons de parvenir à temps sur les meilleures zones de frayères, notamment ceux qui se présentent à l'automne sur le gave, ou ceux qui, ralentis par les obstacles, effectuent un arrêt estival sur la partie aval du cours d'eau. Les seuils de stabilisation en enrochements de faible hauteur ( 2,5 m supérieure ont eu des impacts variables, imputables en grande partie au type de passe à poissons. Les passes à bassins et les rivières de contournement ont été les dispositifs de franchissement les plus performants. Les passés à ralentisseurs à chevrons épais se sont révélées peu performantes en raison de leur faible débit d'alimentation et de leur grande sensibilité aux variations des niveaux d'eau amont. L'impact des aménagements hydroélectriques sans dérivation dépend de l'emplacement de l'entrée de la passe à poissons et de son débit d'alimentation : des effets minimums sur la migration ont été observés lorsque les ouvrages étaient équipés d'un dispositif mobilisant des débits importants (2-4 m3/s et dont l'entrée se situait dans le canal de fuite. L'impact des aménagements hydroélectriques munis d'une dérivation, tous équipés d'un dispositif de franchissement au niveau des barrages de prise d'eau, dépend des débits réservés dans les parties court

  7. La cooperación Sur-Sur como instrumento para la inserción internacional del Estado en Brasil y Venezuela

    OpenAIRE

    2012-01-01

    El presente trabajo persigue dos propósitos: Por un lado, analizar en qué medida la creciente resonancia de la Cooperación Sur-Sur (CSS) responde al cambio en la orientación estratégica de la política exterior de los países de América Latina (AL). Por otro lado, observar si la orientación política del gobierno condiciona la importancia y el tipo de CSS que el país promueve. La relación entre la CSS y la orientación estratégica de la política exterior de los países de AL, entendida esta última...

  8. A new MTR fuel for a new MTR reactor: UMo for the Jules Horowitz reactor

    Energy Technology Data Exchange (ETDEWEB)

    Guigon, B. [CEA Cadarache, Dir. de l' Energie Nucleaire DEN, Reacteur Jules Horowitz, 13 - Saint-Paul-lez-Durance (France); Vacelet, H. [Compagnie pour l' Etude et la Realisation de Combustibles Atomiques, CERCA, Etablissement de Romans, 26 (France); Dornbusch, D. [Technicatome, Service d' Architecture Generale, 13 - Aix-en-Provence (France)

    2003-07-01

    Within some years, the Jules Horowitz Reactor will be the only working experimental reactor (material and fuel testing reactor) in France. It will have to provide facilities for a wide range of needs: from activation analysis to power reactor fuel qualification. In this paper will be presented the main characteristics of the Jules Horowitz Reactor: its total power, neutron flux, fuel element... Safety criteria will be explained. Finally merits and disadvantages of UMo compared to the standard U{sub 3}Si{sub 2} fuel will be discussed. (authors)

  9. Annual report on JEN-1 reactor; Informe periodico del Reactor JEN-1 correspondiente al ano 1971

    Energy Technology Data Exchange (ETDEWEB)

    Montes, J.

    1972-07-01

    In the annual report on the JEN-1 reactor the main features of the reactor operations and maintenance are described. The reactor has been critical for 1831 hours, what means 65,8% of the total working time. Maintenance and pool water contamination have occupied the rest of the time. The maintenance schedule is shown in detail according to three subjects. The main failures and reactor scrams are also described. The daily maximum values of the water activity are given so as the activity of the air in the reactor hall. (Author)

  10. Tricotecenos y calidad de granos del Cono Sur

    Directory of Open Access Journals (Sweden)

    Jacqueline Cea

    2011-04-01

    Full Text Available Fusarium es un género de hongo complejo con especies que se adaptan a un amplio rango de habitats. ( Summerell et al.2001. Aunque hay docenas de especies de Fusarium, sólo un número limitado son responsables de la contaminación por micotoxinas en alimentos y raciones ( Marasas et al.1984b. Parte de estas micotoxinas son denominadas tricotecenos , involucrando mayoritariamente al deoxinivalenol (DON, sus derivados acetilados (3-acetyldeoxinivalenol y 15 acetildeoxinivalenol, T2,  HT2 y nivalenol. Según JECFA, los estudios realizados demuestran que el DON aparece predominantemente en granos tales como trigo, cebada, avena, centeno y maíz, y menos frecuentemente en arroz y sorgo. En la mayoría de las regiones del mundo, incluyendo el Cono Sur, Fusarium graminearum es el mayor agente causal de enfermedades de Fusaium en granos y cereales denominadas: Fusarium Head Blight en cereales y  Giberella ear rot en maíz. Se ha encontrado una relación directa entre la incidencia de Fusarium Head Blight y la contaminación de trigo con DON. La incidencia de la enfermedad esta afectada por las condiciones climáticas de lluvia y humedad en el período de la floración. El factor más crítico es el momento de la lluvia más que la cantidad. F. graminearum crece a una temperatura óptima de 25°C y a una actividad de agua de 0.88.Ejemplo de las consecuencias de Fusarium Head Blight en trigo, es lo ocurrido en la zafra 2001-2002 en Uruguay.  El trigo nacional sufrió contaminación con la consecuente producción de DON en valores comprometedores para la salud, tanto humana como animal. Esta situación sirvió como punto de partida para la concientización y toma de decisiones por parte de las autoridades. Es así que el MSP y MGAP establecieron  reglamentaciones con el objetivo de proteger la salud humana y animal. En forma paralela se implementó un Proyecto FAOPCT/URU/2801 de "Apoyo en la prevención y control de Fusarium y micotoxinas en granos

  11. Selective purge for hydrogenation reactor recycle loop

    Science.gov (United States)

    Baker, Richard W.; Lokhandwala, Kaaeid A.

    2001-01-01

    Processes and apparatus for providing improved contaminant removal and hydrogen recovery in hydrogenation reactors, particularly in refineries and petrochemical plants. The improved contaminant removal is achieved by selective purging, by passing gases in the hydrogenation reactor recycle loop or purge stream across membranes selective in favor of the contaminant over hydrogen.

  12. Radiochemical problems of fusion reactors. 1. Facilities

    Energy Technology Data Exchange (ETDEWEB)

    Crespi, M.B.A.

    1984-02-01

    A list of fusion reactor candidate materials is given, for use in connection with blanket structure, breeding, moderation, neutron multiplication, cooling, magnetic field generation, electrical insulation and radiation shielding. The phenomena being studied for each group of materials are indicated. Suitable irradiation test facilities are discussed under the headings (1) accelerator-based neutron sources, (2) fission reactors, and (3) ion accelerators.

  13. Advanced tokamak concepts and reactor designs

    NARCIS (Netherlands)

    Oomens, A. A. M.

    2000-01-01

    From a discussion of fusion reactor designs based on today's well-established experience gained in the operation of large tokamaks, it is concluded that such reactors are economically not attractive. The physics involved in the various options for concept improvement is described, some examples

  14. Startup of an industrial adiabatic tubular reactor

    NARCIS (Netherlands)

    Verwijs, J.W.; Berg, van den H.; Westerterp, K.R.

    1992-01-01

    The dynamic behaviour of an adiabatic tubular plant reactor during the startup is demonstrated, together with the impact of a feed-pump failure of one of the reactants. A dynamic model of the reactor system is presented, and the system response is calculated as a function of experimentally-determine

  15. Rotor for a pyrolysis centrifuge reactor

    DEFF Research Database (Denmark)

    2015-01-01

    The present invention relates to a rotor for a pyrolysis centrifuge reactor, said rotor comprising a rotor body having a longitudinal centre axis, and at least one pivotally mounted blade being adapted to pivot around a pivot axis under rotation of the rotor body around the longitudinal centre axis....... Moreover, the present invention relates to a pyrolysis centrifuge reactor applying such a rotor....

  16. Helix reactor: great potential for flow chemistry

    NARCIS (Netherlands)

    Geerdink, P.; Runstraat, A. van den; Roelands, C.P.M.; Goetheer, E.L.V.

    2009-01-01

    The Helix reactor is highly suited for precise reaction control based on good hydrodynamics. The hydrodynamics are controlled by the Dean vortices, which create excellent heat transfer properties, approach plug flow and avoid turbulence. The flexibility of this reactor has been demonstrated using a

  17. The Design of a Nuclear Reactor

    Indian Academy of Sciences (India)

    2016-09-01

    The aim of this largely pedagogical article is toemploy pre-college physics to arrive at an understanding of a system as complex as a nuclear reactor. We focus on three key issues: the fuelpin, the moderator, and lastly the dimensions ofthe nuclear reactor.

  18. Design of an organic simplified nuclear reactor

    Energy Technology Data Exchange (ETDEWEB)

    Shirvan, Koroush [Dept. of Nuclear Science and Engineering, Massachusetts Institute of Technology, Cambridge (United States); Forrest, Eric [Primary Standards Laboratory, Sandia National Laboratories, Albuquerque (United States)

    2016-08-15

    Numerous advanced reactor concepts have been proposed to replace light water reactors ever since their establishment as the dominant technology for nuclear energy production. While most designs seek to improve cost competitiveness and safety, the implausibility of doing so with affordable materials or existing nuclear fuel infrastructure reduces the possibility of near-term deployment, especially in developing countries. The organic nuclear concept, first explored in the 1950s, offers an attractive alternative to advanced reactor designs being considered. The advent of high temperature fluids, along with advances in hydrocracking and reforming technologies driven by the oil and gas industries, make the organic concept even more viable today. We present a simple, cost-effective, and safe small modular nuclear reactor for offshore underwater deployment. The core is moderated by graphite, zirconium hydride, and organic fluid while cooled by the organic fluid. The organic coolant enables operation near atmospheric pressure and use of plain carbon steel for the reactor tank and primary coolant piping system. The core is designed to mitigate the coolant degradation seen in early organic reactors. Overall, the design provides a power density of 40 kW/L, while reducing the reactor hull size by 40% compared with a pressurized water reactor while significantly reducing capital plant costs.

  19. Technical features of the MR reactor decommissioning

    Directory of Open Access Journals (Sweden)

    Craig David

    2008-01-01

    Full Text Available This paper presents a preliminary technical design for the dismantling of the MR reactor. The goal of the design is the removal of reactor components allowing the re-use of the building for a different nuclear related purpose. The sequence of segmentation procedures is established. Considerations on the size reduction and tooling are presented.

  20. The First Reactor, 40th Anniversary (rev.)

    Energy Technology Data Exchange (ETDEWEB)

    Allardice, Corbin; Trapnell, Edward R; Fermi, Enrico; Fermi, Laura; Williams, Robert C

    1982-12-01

    This booklet, an updated version of the original booklet describing the first nuclear reactor, was written in honor of the 40th anniversary of the first reactor or "pile". It is based on firsthand accounts told to Corbin Allardice and Edward R. Trapnell, and includes recollections of Enrico and Laura Fermi.

  1. MODERATOR ELEMENTS FOR UNIFORM POWER NUCLEAR REACTOR

    Science.gov (United States)

    Balent, R.

    1963-03-12

    This patent describes a method of obtaining a flatter flux and more uniform power generation across the core of a nuclear reactor. The method comprises using moderator elements having differing moderating strength. The elements have an increasing amount of the better moderating material as a function of radial and/or axial distance from the reactor core center. (AEC)

  2. Parametric sensitivity and runaway in tubular reactors

    Energy Technology Data Exchange (ETDEWEB)

    Morbidelli, M.; Varma, A.

    1982-09-01

    Parametric sensitivity of tubular reactors is analyzed to provide critical values of the heat of reaction and heat transfer parameters defining runaway and stable operations for all positive-order exothermic reactions with finite activation energies, and for all reactor inlet temperatures. Evaluation of the critical values does not involve any trial and error.

  3. Microbial degradation of MTBE in reactors

    DEFF Research Database (Denmark)

    Waul, Christopher Kevin; Arvin, Erik; Schmidt, Jens Ejbye

    2007-01-01

    , toluene, ethylbenzene and xylenes, may reduce the removal rates of MTBE, or prevent its removal in reactors. With mathematical modelling, the long startup time required for some MTBE degrading reactors could be predicted. Long startup times of up to 200 days were due to the low maximum growth rate...

  4. Design of an Organic Simplified Nuclear Reactor

    Directory of Open Access Journals (Sweden)

    Koroush Shirvan

    2016-08-01

    Full Text Available Numerous advanced reactor concepts have been proposed to replace light water reactors ever since their establishment as the dominant technology for nuclear energy production. While most designs seek to improve cost competitiveness and safety, the implausibility of doing so with affordable materials or existing nuclear fuel infrastructure reduces the possibility of near-term deployment, especially in developing countries. The organic nuclear concept, first explored in the 1950s, offers an attractive alternative to advanced reactor designs being considered. The advent of high temperature fluids, along with advances in hydrocracking and reforming technologies driven by the oil and gas industries, make the organic concept even more viable today. We present a simple, cost-effective, and safe small modular nuclear reactor for offshore underwater deployment. The core is moderated by graphite, zirconium hydride, and organic fluid while cooled by the organic fluid. The organic coolant enables operation near atmospheric pressure and use of plain carbon steel for the reactor tank and primary coolant piping system. The core is designed to mitigate the coolant degradation seen in early organic reactors. Overall, the design provides a power density of 40 kW/L, while reducing the reactor hull size by 40% compared with a pressurized water reactor while significantly reducing capital plant costs.

  5. Políticas culturales: Francia y Europa del Sur Políticas culturales: Francia y Europa del Sur

    Directory of Open Access Journals (Sweden)

    Emmanuel Négrier

    2008-04-01

    Full Text Available In this paper, we propose a comparative analysis of five national models of cultural policy. The four first ones constitute Southern Europe: Greece, Italy, Portugal and Spain. The fifth one is France. These countries share a tradition of direct intervention in the cultural field, contrary to anglo-saxon or Scandinavian countries. The aim of such a comparison is to assess convergences but also disparities between these countries, in spite of their common traditions. We focus on the historical paths, the ways of institutionalization of the cultural public domain, and the different kinds of territorial management of cultural policies. France, which is often considered as a singular model the other countries would have try to imitate, is also analyzed in a comparative perspective. The assessment of convergences and divergences allows, in conclusion, to establish the common goals that share these five countries, as well as the major part of occidental countries in order to define the cultural policy for the 21st century.En este artículo ofrecemos un análisis comparado de cinco modelos nacionales de política cultural. Los cuatro primeros pertenecen a la Europa del sur: España, Grecia, Italia, Portugal; Francia es el quinto. A diferencia de los países anglosajones o escandinavos, los países mencionados tienen en común una tradición de intervención directa en materia de cultura. Nuestra comparación se propone demostrar las convergencias y las diferencias en las trayectorias históricas de dichas políticas culturales, su forma de institucionalización y su modo de gestión territorial. Abordamos el caso francés aparte y desde una perspectiva comparada, pues suele constituir un modelo que los otros cuatro países han intentado imitar. A modo de conclusión, el balance de las convergencias y divergencias permite establecer retos comunes para el conjunto de dichos países, y quizá también para todos los países occidentales, de cara a definir

  6. Verification of Remote Inspection Techniques for Reactor Internal Structures of Liquid Metal Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Joo, Young Sang; Lee, Jae Han

    2007-02-15

    The reactor internal structures and components of a liquid metal reactor (LMR) are submerged in hot sodium of reactor vessel. The division 3 of ASME code section XI specifies the visual inspection as major in-service inspection (ISI) methods of reactor internal structures and components. Reactor internals of LMR can not be visually examined due to opaque liquid sodium. The under-sodium viewing techniques using an ultrasonic wave should be applied for the visual inspection of reactor internals. Recently, an ultrasonic waveguide sensor with a strip plate has been developed for an application to the under-sodium inspection. In this study, visualization technique, ranging technique and monitoring technique have been suggested for the remote inspection of reactor internals by using the waveguide sensor. The feasibility of these remote inspection techniques using ultrasonic waveguide sensor has been evaluated by an experimental verification.

  7. State space modeling of reactor core in a pressurized water reactor

    Energy Technology Data Exchange (ETDEWEB)

    Ashaari, A.; Ahmad, T.; M, Wan Munirah W. [Department of Mathematical Science, Faculty of Science, Universiti Teknologi Malaysia, 81310 Skudai, Johor (Malaysia); Shamsuddin, Mustaffa [Institute of Ibnu Sina, Universiti Teknologi Malaysia, 81310 Skudai, Johor (Malaysia); Abdullah, M. Adib [Swinburne University of Technology, Faculty of Engineering, Computing and Science, Jalan Simpang Tiga, 93350 Kuching, Sarawak (Malaysia)

    2014-07-10

    The power control system of a nuclear reactor is the key system that ensures a safe operation for a nuclear power plant. However, a mathematical model of a nuclear power plant is in the form of nonlinear process and time dependent that give very hard to be described. One of the important components of a Pressurized Water Reactor is the Reactor core. The aim of this study is to analyze the performance of power produced from a reactor core using temperature of the moderator as an input. Mathematical representation of the state space model of the reactor core control system is presented and analyzed in this paper. The data and parameters are taken from a real time VVER-type Pressurized Water Reactor and will be verified using Matlab and Simulink. Based on the simulation conducted, the results show that the temperature of the moderator plays an important role in determining the power of reactor core.

  8. State space modeling of reactor core in a pressurized water reactor

    Science.gov (United States)

    Ashaari, A.; Ahmad, T.; Shamsuddin, Mustaffa; M, Wan Munirah W.; Abdullah, M. Adib

    2014-07-01

    The power control system of a nuclear reactor is the key system that ensures a safe operation for a nuclear power plant. However, a mathematical model of a nuclear power plant is in the form of nonlinear process and time dependent that give very hard to be described. One of the important components of a Pressurized Water Reactor is the Reactor core. The aim of this study is to analyze the performance of power produced from a reactor core using temperature of the moderator as an input. Mathematical representation of the state space model of the reactor core control system is presented and analyzed in this paper. The data and parameters are taken from a real time VVER-type Pressurized Water Reactor and will be verified using Matlab and Simulink. Based on the simulation conducted, the results show that the temperature of the moderator plays an important role in determining the power of reactor core.

  9. Precision spectroscopy with reactor anti-neutrinos

    CERN Document Server

    Huber, P; Huber, Patrick; Schwetz, Thomas

    2004-01-01

    In this work we present an accurate parameterization of the anti-neutrino flux produced by the isotopes 235U, 239Pu and 241Pu in nuclear reactors. We determine the coefficients of this parameterization, as well as their covariance matrix, by performing a fit to spectra inferred from experimentally measured beta spectra. Subsequently we show that flux shape uncertainties play only a minor role in the KamLAND experiment, however, we find that future reactor neutrino experiments to measure the mixing angle $\\theta_{13}$ are sensitive to the fine details of the reactor neutrino spectra. Finally, we investigate the possibility to determine the isotopic composition in nuclear reactors through an anti-neutrino measurement. We find that with a 3 month exposure of a one ton detector the isotope fractions and the thermal reactor power can be determined at a few percent accuracy, which may open the possibility of an application for safeguard or non-proliferation objectives.

  10. Scanning tunneling microscope assembly, reactor, and system

    Science.gov (United States)

    Tao, Feng; Salmeron, Miquel; Somorjai, Gabor A

    2014-11-18

    An embodiment of a scanning tunneling microscope (STM) reactor includes a pressure vessel, an STM assembly, and three spring coupling objects. The pressure vessel includes a sealable port, an interior, and an exterior. An embodiment of an STM system includes a vacuum chamber, an STM reactor, and three springs. The three springs couple the STM reactor to the vacuum chamber and are operable to suspend the scanning tunneling microscope reactor within the interior of the vacuum chamber during operation of the STM reactor. An embodiment of an STM assembly includes a coarse displacement arrangement, a piezoelectric fine displacement scanning tube coupled to the coarse displacement arrangement, and a receiver. The piezoelectric fine displacement scanning tube is coupled to the coarse displacement arrangement. The receiver is coupled to the piezoelectric scanning tube and is operable to receive a tip holder, and the tip holder is operable to receive a tip.

  11. Reactor assessments of advanced bumpy torus configurations

    Energy Technology Data Exchange (ETDEWEB)

    Uckan, N.A.; Owen, L.W.; Spong, D.A.; Miller, R.L.; Ard, W.B.; Pipkins, J.F.; Schmitt, R.J.

    1984-02-01

    Recently, several innovative approaches were introduced for enhancing the performance of the basic ELMO Bumpy Torus (EBT) concept and for improving its reactor potential. These include planar racetrack and square geometries, Andreoletti coil systems, and bumpy torus-stellarator hybrids (which include twisted racetrack and helical axis stellarator - snakey torus). Preliminary evaluations of reactor implications of each approach have been carried out based on magnetics (vacuum) calculations, transport and scaling relationships, and stability properties deduced from provisional configurations that implement the approach but are not necessarily optimized. Further optimization is needed in all cases to evaluate the full potential of each approach. Results of these studies indicate favorable reactor projections with a significant reduction in reactor physical size as compared to conventional EBT reactor designs carried out in the past.

  12. Reactivity control assembly for nuclear reactor. [LMFBR

    Science.gov (United States)

    Bollinger, L.R.

    1982-03-17

    This invention, which resulted from a contact with the United States Department of Energy, relates to a control mechanism for a nuclear reactor and, more particularly, to an assembly for selectively shifting different numbers of reactivity modifying rods into and out of the core of a nuclear reactor. It has been proposed heretofore to control the reactivity of a breeder reactor by varying the depth of insertion of control rods (e.g., rods containing a fertile material such as ThO/sub 2/) in the core of the reactor, thereby varying the amount of neutron-thermalizing coolant and the amount of neutron-capturing material in the core. This invention relates to a mechanism which can advantageously be used in this type of reactor control system.

  13. Power Control Method for Research Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Baang, Dane; Suh, Yongsuk; Park, Cheol [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2015-05-15

    Considering safety-oriented design concept and other control environment, we developed a simple controller that provides limiting function of power change- rate as well as fine tracking performance. The design result has been well-proven via simulation and actual application to a TRIGA-II type research reactor. The proposed controller is designed to track the PDM(Power Demand) from operator input as long as maintaining the power change rate lower than a certain value for stable reactor operation. A power control method for a TRIGA-II type research reactor has been designed, simulated, and applied to actual reactor. The control performance during commissioning test shows that the proposed controller provides fine control performance for various changes in reference values (PDM), even though there is large measurement noise from neutron detectors. The overshoot at low power level is acceptable in a sense of reactor operation.

  14. Ceramic oxygen transport membrane array reactor and reforming method

    Science.gov (United States)

    Kelly, Sean M.; Christie, Gervase Maxwell; Robinson, Charles; Wilson, Jamie R.; Gonzalez, Javier E.; Doraswami, Uttam R.

    2016-11-08

    The invention relates to a commercially viable modular ceramic oxygen transport membrane reforming reactor configured using repeating assemblies of oxygen transport membrane tubes and catalytic reforming reactors.

  15. Fast Spectrum Molten Salt Reactor Options

    Energy Technology Data Exchange (ETDEWEB)

    Gehin, Jess C [ORNL; Holcomb, David Eugene [ORNL; Flanagan, George F [ORNL; Patton, Bruce W [ORNL; Howard, Rob L [ORNL; Harrison, Thomas J [ORNL

    2011-07-01

    During 2010, fast-spectrum molten-salt reactors (FS-MSRs) were selected as a transformational reactor concept for light-water reactor (LWR)-derived heavy actinide disposition by the Department of Energy-Nuclear Energy Advanced Reactor Concepts (ARC) program and were the subject of a preliminary scoping investigation. Much of the reactor description information presented in this report derives from the preliminary studies performed for the ARC project. This report, however, has a somewhat broader scope-providing a conceptual overview of the characteristics and design options for FS-MSRs. It does not present in-depth evaluation of any FS-MSR particular characteristic, but instead provides an overview of all of the major reactor system technologies and characteristics, including the technology developments since the end of major molten salt reactor (MSR) development efforts in the 1970s. This report first presents a historical overview of the FS-MSR technology and describes the innovative characteristics of an FS-MSR. Next, it provides an overview of possible reactor configurations. The following design features/options and performance considerations are described including: (1) reactor salt options-both chloride and fluoride salts; (2) the impact of changing the carrier salt and actinide concentration on conversion ratio; (3) the conversion ratio; (4) an overview of the fuel salt chemical processing; (5) potential power cycles and hydrogen production options; and (6) overview of the performance characteristics of FS-MSRs, including general comparative metrics with LWRs. The conceptual-level evaluation includes resource sustainability, proliferation resistance, economics, and safety. The report concludes with a description of the work necessary to begin more detailed evaluation of FS-MSRs as a realistic reactor and fuel cycle option.

  16. Radiation protection at new reactors

    Energy Technology Data Exchange (ETDEWEB)

    Brissaud, A. [EDF INDUSTRY, Basic Design Department, EDF-SEPTEN, VILLEURBANNE Cedex (France)

    2000-05-01

    The theoritical knowledge and the feedback of operating experience concerning radiations in reactors is now considerable. It is available to the designer in the form of predictive softwares and data bases. Thus, it is possible to include the radiation protection component throughout all the design process. In France, the existing reactors have not been designed with quantified radiation protection targets, although considerable efforts have been made to reduce sources of radiation illustrated by the decrease of the average dose rates (typically a factor 5 between the first 900 MWe and the last 1300 MWe units). The EDF ALARA PROJECT has demonstrated that good practises, radiation protection awareness, careful work organization had a strong impact on operation and maintenance work volume. A decrease of the average collective dose by a factor 2 has been achieved without noticeable modifications of the units. In the case of new nuclear facilities projects (reactor, intermediate storage facility,...), or special operations (such as steam generator replacement), quantified radiation protection targets are included in terms of collective and average individual doses within the frame of a general optimization scheme. The target values by themselves are less important than the application of an optimization process throughout the design. This is because the optimization process requires to address all the components of the dose, particularly the work volume for operation and maintenance. A careful study of this parameter contributes to the economy of the project (suppression of unecessary tasks, time-saving ergonomy of work sites). This optimization process is currently applied to the design of the EPR. General radiation protection provisions have been addressed during the basic design phase by applying general rules aiming at the reduction of sources and dose rates. The basic design optimization phase has mainly dealt with the possibility to access the containment at full

  17. Comment enquêter sur une émeute ?

    Directory of Open Access Journals (Sweden)

    Olivier Galland

    2007-08-01

    Full Text Available En novembre 2005, la France a été touchée par une vague de violences urbaines inédites. Issu d’une enquête monographique menée dans la ville d’Aulnay-sous-Bois (au nord de Paris, cet article souhaite revenir sur le terrain, en mettant en lumière d’une part ses aspérités, en prenant d’autre part très au sérieux la parole des jeunes impliqués, directement ou pas, dans ces évènements. Considérant les interviewés comme « capables » de dire leur expérience (en leur donnant un sens, nous avons fait état de la pluralité des versions que les jeunes ont donné de ces évènements, en formalisant leurs tentatives au travers de trois grandes figures explicatives (l’émeute déviante, l’émeute protestataire et l’émeute ludique.France was affected by an unseen wave of riots in November 2005. This paper comes from a monographic survey made in Aulnay-sous-Bois (a town in the north of Paris. This paper aims to focus on some significant difficulties during the fieldwork. We also attempt to take seriously the discourse of the young interviewees (those actively involved as well as those not actively involved in these events. We have considered our interviewees as “able” to tell their experiences and to give them a meaning. Thanks to this attitude, this survey found out that young people gave several versions of the riots summarised in three great explanations: for them these riots were the result of deviance, protest or a game.En Noviembre de 2005 Francia fue afectada por una oleada de violencia urbana inédita hasta entonces. Fruto de una investigación monográfica realizada en la ciudad de Aulnay-sous-Bois (al norte de París, este artículo desea volver a estos hechos, por un lado para poner de relieve la dificultad de la investigación, y por otro, para dar voz  a los jóvenes implicados, directamente o no, en estos acontecimientos. Considerando a los protagonistas sociales “capaces” de contar su experiencia

  18. PCCF flow analysis -- DR Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Calkin, J.F.

    1961-04-26

    This report contains an analysis of PCCF tube flow and Panellit pressure relations at DR reactor. Supply curves are presented at front header pressures from 480 to 600 psig using cold water and the standard 0.236 inch orifice with taper down stream and the pigtail valve (plug or ball) open. Demand curves are presented for slug column lengths of 200 inches to 400 inches using 1.44 inch O.D. solid poison pieces (either Al or Pb-Cd) and cold water with a rear header pressure of 50 psig. Figure 1 is a graph of Panellit pressure vs. flow with the above supply and demand curves and clearly shows the effect of front header pressure and charge length on flow.

  19. Coacervates as prebiotic chemical reactors

    Science.gov (United States)

    Kolb, Vera M.; Swanson, Mercedes; Menger, Fredric M.

    2012-10-01

    Coacervates are colloidal systems that are comprised of two immiscible aqueous layers, the colloid-rich layer, so-called coacervate, and the colloid-poor layer, so-called equilibrium liquid. Although immiscible, the two phases are both water-rich. Coacervates are important for prebiotic chemistry, but also have various practical applications, notably as transport vehicles of personal care products and pharmaceuticals. Our objectives are to explore the potential of coacervates as prebiotic chemical reactors. Since the reaction medium in coacervates is water, this creates a challenge, since most organic reactants are not water-soluble. To overcome this challenge we are utilizing recent Green Chemistry examples of the organic reactions in water, such as the Passerini reaction. We have investigated this reaction in two coacervate systems, and report here our preliminary results.

  20. Replacement reactor to revolutionise magnets

    CERN Document Server

    Atkins, G

    2002-01-01

    Electric motors, hearing aids and magnetic resonance imaging are only some of the applications that will benefit from the first advances in magnets in a quarter of a century. Magnets achieve their characteristics when electrons align themselves to produce a unified magnetic field. Neutrons can probe these magnetic structures. The focus is not just on making more powerful magnets, but also identifying the characteristics that make magnets cheaper and easier for industry to manufacture. Staff from the ANSTO's Neutron Scattering Group have already performed a number of studies on the properties of magnets using using HIFAR, but the Replacement Research Reactor that will produce cold neutrons would allow scientists to investigate the atomic properties of materials with large molecules. A suite of equipment will enable studies at different temperatures, pressures and magnetic fields

  1. Dynamic analysis of process reactors

    Energy Technology Data Exchange (ETDEWEB)

    Shadle, L.J.; Lawson, L.O.; Noel, S.D.

    1995-06-01

    The approach and methodology of conducting a dynamic analysis is presented in this poster session in order to describe how this type of analysis can be used to evaluate the operation and control of process reactors. Dynamic analysis of the PyGas{trademark} gasification process is used to illustrate the utility of this approach. PyGas{trademark} is the gasifier being developed for the Gasification Product Improvement Facility (GPIF) by Jacobs-Siffine Engineering and Riley Stoker. In the first step of the analysis, process models are used to calculate the steady-state conditions and associated sensitivities for the process. For the PyGas{trademark} gasifier, the process models are non-linear mechanistic models of the jetting fluidized-bed pyrolyzer and the fixed-bed gasifier. These process sensitivities are key input, in the form of gain parameters or transfer functions, to the dynamic engineering models.

  2. Reactor operation environmental information document

    Energy Technology Data Exchange (ETDEWEB)

    Wike, L.D.; Specht, W.L.; Mackey, H.E.; Paller, M.H.; Wilde, E.W.; Dicks, A.S.

    1989-12-01

    The Savannah River Site (SRS) is a large United States Department of Energy installation on the upper Atlantic Coastal Plain of South Carolina. The SRS contains diverse habitats, flora, and fauna. Habitats include upland terrestrial areas, varied wetlands including Carolina Bays, the Savannah River swamp system, and impoundment related and riparian wetlands, and the aquatic habitats of several stream systems, two large cooling reservoirs, and the Savannah River. These diverse habitats support a large variety of plants and animals including many commercially or recreational valuable species and several rare, threatened or endangered species. This volume describes the major habitats and their biota found on the SRS, and discuss the impacts of continued operation of the K, L, and P production reactors.

  3. (Meeting on fusion reactor materials)

    Energy Technology Data Exchange (ETDEWEB)

    Jones, R.H. (Pacific Northwest Lab., Richland, WA (USA)); Klueh, R.L.; Rowcliffe, A.F.; Wiffen, F.W. (Oak Ridge National Lab., TN (USA)); Loomis, B.A. (Argonne National Lab., IL (USA))

    1990-11-01

    During his visit to the KfK, Karlsruhe, F. W. Wiffen attended the IEA 12th Working Group Meeting on Fusion Reactor Materials. Plans were made for a low-activation materials workshop at Culham, UK, for April 1991, a data base workshop in Europe for June 1991, and a molecular dynamics workshop in the United States in 1991. At the 11th IEA Executive Committee on Fusion Materials, discussions centered on the recent FPAC and Colombo panel review in the United States and EC, respectively. The Committee also reviewed recent progress toward a neutron source in the United States (CWDD) and in Japan (ESNIT). A meeting with D. R. Harries (consultant to J. Darvas) yielded a useful overview of the EC technology program for fusion. Of particular interest to the US program is a strong effort on a conventional ferritic/martensitic steel for fist wall/blanket operation beyond NET/ITER.

  4. The use of seemingly unrelated regression (SUR) to predict the carcass composition of lambs

    DEFF Research Database (Denmark)

    Cadavez, Vasco A. P.; Henningsen, Arne

    particularly focussed on the PRESS statistic, because it assesses the precision of the model in predicting carcass composition. Our results showed that the SUR estimator performed better in predicting LMP and IFP than the OLS estimator. Although objective carcass classification systems could be improved...

  5. INFLUENCE DE LA PROPOLIS SUR LA MITOSE DANS LE MERYSTEME DE SECALE CEREALE L.

    OpenAIRE

    Mioara Navrotescu; Ovidiu Toma

    2005-01-01

    Cette recherche présente l’influence de propolis sur la mitose dans le merysteme de Secale cereale L. (2n=14). On confirme l’utilisation de plus en plus large de ce produit apicole - propolis - au niveau de la thérapeutique.

  6. Aircraft Operations on Repaired Runways (l’Exploitation des Aeronefs sur les Pistes Refaites)

    Science.gov (United States)

    1990-08-01

    procedures d’cxploitaiion des acronels sur des pistes repar&s. le Panel AGiARI) des Structures ct Materiaux at organisii des reunions pour faire Ic...is available for cncrgy absorption to ground roughness can be much improved whie incurring and lowering tile -stiffness Of the suspension . Increased

  7. Decontamination tests on cotton materials; Essais de decontamination sur tissus de coton

    Energy Technology Data Exchange (ETDEWEB)

    Cohen, P.; Pelletier, C. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1958-07-01

    It is shown that versene gives the best decontamination results on cotton materials soiled by a mixture of fission products. (author) [French] On a montre que le versene donne les meilleurs resultats de decontamination sur des tissus de coton souilles par un melange de produits de fission. (auteur)

  8. Lois du travail applicables sur les sites CERN, notamment le site de Meyrin

    CERN Document Server

    López-Hernandez, L A

    2005-01-01

    Le CERN passe des contrats avec des entreprises dont le personnel peut être amené à travailler sur le domaine de l’Organisation. Comme principe général, ces entreprises sont soumises au Droit de leur pays d’origine, mais elles doivent respecter aussi les dispositions d’ordre public du pays où elles exercent leur activité, c’est à dire les dispositions suisses sur la partie suisse et les dispositions françaises sur la partie française du domaine. Les dispositions d’ordre public sont des dispositions de droit fondamental qui couvrent, entre autres, des aspects relatifs aux conditions de travail (durée du travail, rémunération), la sécurité et la protection de la santé. La situation particulière du CERN, dont les sites sont situés aussi bien en France qu’en Suisse, fait que les entreprises sous contrat peuvent être amenées à travailler sur ces deux pays, parfois simultanément, avec des dispositions de droit du travail complètement différentes. L’application stricte de la lé...

  9. INFLUENCE DE LA PROPOLIS SUR LA MITOSE DANS LE MERYSTEME DE SECALE CEREALE L.

    Directory of Open Access Journals (Sweden)

    Mioara Navrotescu

    2005-08-01

    Full Text Available Cette recherche présente l’influence de propolis sur la mitose dans le merysteme de Secale cereale L. (2n=14. On confirme l’utilisation de plus en plus large de ce produit apicole - propolis - au niveau de la thérapeutique.

  10. Handbook on Long Term Defence Planning (Manuel sur la planification de defense a long terme)

    Science.gov (United States)

    2003-04-01

    ses mécanismes. On aborde également, dans le cadre de ce processus, le contexte de la planification et la traduction des plans en mesures exécutives...et technique (STI) (accessible également en mode interactif dans la base de données bibliographiques en ligne du NTIS, et sur CD-ROM)STI Program

  11. L'exploration des données géographiques sur REGARD

    Directory of Open Access Journals (Sweden)

    Anthony UNWIN

    1994-09-01

    Full Text Available Le logiciel REGARD offre des outils graphiques interactifs d’exploration des données spatiales. Son utilisation est illustrée ici par un ensemble de données sur l’environnement et la reproduction des oiseaux en Écosse.

  12. Reflections on "Petit Battement sur le Cou de Pied": Is It Still Relevant?

    Science.gov (United States)

    Paskevska, Anna

    2007-01-01

    This article presents multiple perspectives of "petit battement sur le cou de pied". These perspectives include historical, biomechanical, and pedagogic points of view. The article offers useful information for ballet specialists and applied research studies aimed at ballet pedagogy. (Contains 2 tables and 5 figures.)

  13. Flexible Conversion Ratio Fast Reactor Systems Evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Neil Todreas; Pavel Hejzlar

    2008-06-30

    Conceptual designs of lead-cooled and liquid salt-cooled fast flexible conversion ratio reactors were developed. Both concepts have cores reated at 2400 MWt placed in a large-pool-type vessel with dual-free level, which also contains four intermediate heat exchanges coupling a primary coolant to a compact and efficient supercritical CO2 Brayton cycle power conversion system. Decay heat is removed passively using an enhanced Reactor Vessel Auxiliary Cooling System and a Passive Secondary Auxiliary Cooling System. The most important findings were that (1) it is feasible to design the lead-cooled and salt-cooled reactor with the flexible conversion ratio (CR) in the range of CR=0 and CR=1 n a manner that achieves inherent reactor shutdown in unprotected accidents, (2) the salt-cooled reactor requires Lithium thermal Expansion Modules to overcme the inherent salt coolant's large positive coolant temperature reactivity coefficient, (3) the preferable salt for fast spectrum high power density cores is NaCl-Kcl-MgCl2 as opposed to fluoride salts due to its better themal-hydraulic and neutronic characteristics, and (4) both reactor, but attain power density 3 times smaller than that of the sodium-cooled reactor.

  14. The Swedish Zero Power Reactor R0

    Energy Technology Data Exchange (ETDEWEB)

    Landergaard, Olof; Cavallin, Kaj; Jonsson, Georg

    1961-05-15

    The reactor R0 is a critical facility built for heavy water and natural uranium or fuel of low enrichment,, The first criticality was achieved September 25, 1959. During a first period of more than two years the R0 will be operated as a bare reactor in order to simplify interpretation of results. The reactor tank is 3. 2 m high and 2. 25 m in diameter. The fuel suspension system is quite flexible in order to facilitate fuel exchange and lattice variations. The temperature of the water can be varied between about 10 and 90 C by means of a heater and a cooler placed in the external circulating system. The instrumentation of the reactor has to meet the safety requirements not only during operation but also during rearrangements of the core in the shut-down state. Therefore, the shut-down state is always defined by a certain low 'safe' moderator level in the reactor tank. A number of safety rods are normally kept above the moderator ready for action. For manual or automatic control of the reactor power a specially designed piston pump is needed, by which the moderator level is varied. The pump speed is controlled from the reactor power error by means of a Ward-Leonard system. Moderator level measurement is made by means of a water gauge with an accuracy of {+-} 0. 1 mm.

  15. Sur le discours et l’histoire en foucault. Entretien avec Jacques Guilhaumou

    Directory of Open Access Journals (Sweden)

    Welisson Marques

    2013-08-01

    Full Text Available Dans cet entretien inédit, Jaques Guilhaumou parle sur la question du discours et de l´histoire dans la pensée de Michel Foucault en regardant telles questions à partir du belvédère de l’Analyse du Discours selon la perception française. Il commence en présentant un panorama de ses travaux plus actuels et souligne ensuite le rôle décisif de Foucault dans le établissement de une nouvelle relation entre le discours et l´histoire. Dans cette direction, il donne des détails sur quelques influences épistémologiques de la pensée foucaultienne qui viennent surtout de Nietzsche et Koselleck. Comme un grand étudiant de la pensée marxiste, Guilhaumou parle aussi sur le concept de l´ideologie et ses plusières métamorphoses conceptuelles dans autres champs jusqu´au moment de parler sur la question du pouvoir. Il parle quand même sur la problématique de l´analyse des images dans l´Analyse du Discours, une question favorable pour beaucoup des analystes du discours qui s´occupent avec le syncrétisme sémiotique des ses objets dans l´actualité. Enfin, il indique l´existence de une théorie du discours diluée dans la pensée du philosophe.

  16. Ficus sur (Moraceae and Gymnanthemum coloratum (Asteraceae: Vernonieae – first distribution records for Namibia

    Directory of Open Access Journals (Sweden)

    Wessel Swanepoel

    2015-03-01

    Full Text Available Background: The distribution of Ficus sur includes most of tropical Africa, but whilst this species was suspected to occur in Namibia, this has not been verified. Gymnanthemum coloratum is a tropical African savannah shrub or tree that has been recorded for Botswana, Swaziland and South Africa, but which has not previously been recorded for Namibia.Objectives: To formally document the first records of two plant species from Namibia and provide habitat details of the localities from which these species were recorded.Method: The data presented have resulted from botanical expeditions to the poorly known Baynes Mountains in the Koakoveld region of Namibia. Specimens of the two species in the National Herbarium, Pretoria were examined to verify the identity in the case of G. coloratum, and to document additional records in Namibia for F. sur.Results: Ficus sur was recorded from two localities, and a third locality based on a specimen in the National Herbarium, Pretoria, was verified. Gymnanthemum coloratum, a member of the Asteraceae, was recorded from a single locality.Conclusion: The fact that F. sur was collected at more than one location in the Kaokoveld suggests that it is probably more widespread in suitable microhabitats. Ficus sur also occurs further north in Angola, suggesting that the Kaokoveld plants represent a cross-border outlier of the much more widespread Angolan population. Gymnanthemum coloratum was only recorded from the one locality in the Koakoveld. The species also occurs in Angola, which suggests that the Kaokoveld plant represents a cross-border outlier of the population in that country.

  17. Facility for a Low Power Research Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Chalker, R. G.

    1949-09-14

    Preliminary investigation indicates that a reactor facility with ample research provisions for use by University or other interested groups, featuring safety in design, can be economically constructed in the Los Angeles area. The complete installation, including an underground gas-tight reactor building, with associated storage and experiment assembly building, administration offices, two general laboratory buildings, hot latoratory and lodge, can be constructed for approxinately $1,500,000. This does not include the cost of the reactor itself or of its auxiliary equipment,

  18. Pyrometric fuel particle measurements in pressurised reactors

    Energy Technology Data Exchange (ETDEWEB)

    Hernberg, R.; Joutsenoja, T. [Tampere Univ. of Technology (Finland)

    1996-12-01

    A fiberoptic two-colour pyrometric technique for fuel particle temperature and size measurement is modified and applied to three pressurized reactors of different type in Finland, Germany and France. A modification of the pyrometric method for simultaneous in situ measurement of the temperature and size of individual pulverized coal particles at the pressurized entrained flow reactor in Jyvaeskylae was developed and several series of measurements were made. In Orleans a fiberoptic pyrometric device was installed to a pressurised thermogravimetric reactor and the two-colour temperatures of fuel samples were measured. Some results of these measurements are presented. The project belongs to EU`s Joule 2 extension research programme. (author)

  19. Oxidation performance of graphite material in reactors

    Institute of Scientific and Technical Information of China (English)

    Xiaowei LUO; Xinli YU; Suyuan YU

    2008-01-01

    Graphite is used as a structural material and moderator for high temperature gas-cooled reactors (HTGR). When a reactor is in operation, graphite oxida-tion influences the safety and operation of the reactor because of the impurities in the coolant and/or the acci-dent conditions, such as water ingress and air ingress. In this paper, the graphite oxidation process is introduced, factors influencing graphite oxidation are analyzed and discussed, and some new directions for further study are pointed out.

  20. Sistemas de salvaguardia en reactores EPR

    OpenAIRE

    2015-01-01

    En este documento se describe brevemente el funcionamiento de los diversos sistemas de una planta nuclear operada con un reactor de tipo PWR. Más concretamente, el proyecto se centra en una descripción exhaustiva de los sistemas de salvaguardia y seguridad que regulan el funcionamiento de un reactor de tipo EPR, así como la central nuclear que contiene a dicho reactor. El proceso ha consistido en clasificar y resumir los distintos sistemas que operan en dicha planta, estudiando sus caracterís...

  1. Packed fluidized bed blanket for fusion reactor

    Science.gov (United States)

    Chi, John W. H.

    1984-01-01

    A packed fluidized bed blanket for a fusion reactor providing for efficient radiation absorption for energy recovery, efficient neutron absorption for nuclear transformations, ease of blanket removal, processing and replacement, and on-line fueling/refueling. The blanket of the reactor contains a bed of stationary particles during reactor operation, cooled by a radial flow of coolant. During fueling/refueling, an axial flow is introduced into the bed in stages at various axial locations to fluidize the bed. When desired, the fluidization flow can be used to remove particles from the blanket.

  2. Monitoring and control of anaerobic reactors

    DEFF Research Database (Denmark)

    Pind, Peter Frode; Angelidaki, Irini; Ahring, Birgitte Kiær;

    2003-01-01

    measurements are reviewed in detail. In the sequel, possible manipulated variables, such as the hydraulic retention time, the organic loading rate, the sludge retention time, temperature, pH and alkalinity are evaluated with respect to the two main reactor types: high-rate and low-rate. Finally, the different......The current status in monitoring and control of anaerobic reactors is reviewed. The influence of reactor design and waste composition on the possible monitoring and control schemes is examined. After defining the overall control structure, and possible control objectives, the possible process...

  3. Transients in reactors for power systems compensation

    Science.gov (United States)

    Abdul Hamid, Haziah

    This thesis describes new models and investigations into switching transient phenomena related to the shunt reactors and the Mechanically Switched Capacitor with Damping Network (MSCDN) operations used for reactive power control in the transmission system. Shunt reactors and MSCDN are similar in that they have reactors. A shunt reactor is connected parallel to the compensated lines to absorb the leading current, whereas the MSCDN is a version of a capacitor bank designed as a C-type filter for use in the harmonic-rich environment. In this work, models have been developed and transient overvoltages due to shunt reactor deenergisation were estimated analytically using MathCad, a mathematical program. Computer simulations used the ATP/EMTP program to reproduce both single-phase and three-phase shunt reactor switching at 275 kV operational substations. The effect of the reactor switching on the circuit breaker grading capacitor was also examined by considering various switching conditions.. The main original achievement of this thesis is the clarification of failure mechanisms occurring in the air-core filter reactor due to MSCDN switching operations. The simulation of the MSCDN energisation was conducted using the ATP/EMTP program in the presence of surge arresters. The outcome of this simulation shows that extremely fast transients were established across the air-core filter reactor. This identified transient event has led to the development of a detailed air-core reactor model, which accounts for the inter-turn RLC parameters as well as the stray capacitances-to-ground. These parameters are incorporated into the transient simulation circuit, from which the current and voltage distribution across the winding were derived using electric field and equivalent circuit modelling. Analysis of the results has revealed that there are substantial dielectric stresses imposed on the winding insulation that can be attributed to a combination of three factors. (i) First, the

  4. Assessing Pretreatment Reactor Scaling Through Empirical Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Lischeske, James J.; Crawford, Nathan C.; Kuhn, Erik; Nagle, Nicholas J.; Schell, Daniel J.; Tucker, Melvin P.; McMillan, James D.; Wolfrum, Edward J.

    2016-12-01

    Pretreatment is a critical step in the biochemical conversion of lignocellulosic biomass to fuels and chemicals. Due to the complexity of the physicochemical transformations involved, predictively scaling up technology from bench- to pilot-scale is difficult. This study examines how pretreatment effectiveness under nominally similar reaction conditions is influenced by pretreatment reactor design and scale using four different pretreatment reaction systems ranging from a 3 g batch reactor to a 10 dry-ton/d continuous reactor. The reactor systems examined were an Automated Solvent Extractor (ASE), Steam Explosion Reactor (SER), ZipperClave(R) reactor (ZCR), and Large Continuous Horizontal-Screw Reactor (LHR). To our knowledge, this is the first such study performed on pretreatment reactors across a range of reaction conditions (time and temperature) and at different reactor scales. The comparative pretreatment performance results obtained for each reactor system were used to develop response surface models for total xylose yield after pretreatment and total sugar yield after pretreatment followed by enzymatic hydrolysis. Near- and very-near-optimal regions were defined as the set of conditions that the model identified as producing yields within one and two standard deviations of the optimum yield. Optimal conditions identified in the smallest-scale system (the ASE) were within the near-optimal region of the largest scale reactor system evaluated. A reaction severity factor modeling approach was shown to inadequately describe the optimal conditions in the ASE, incorrectly identifying a large set of sub-optimal conditions (as defined by the RSM) as optimal. The maximum total sugar yields for the ASE and LHR were 95%, while 89% was the optimum observed in the ZipperClave. The optimum condition identified using the automated and less costly to operate ASE system was within the very-near-optimal space for the total xylose yield of both the ZCR and the LHR, and was

  5. Shape optimization of a Sodium Fast Reactor core

    Directory of Open Access Journals (Sweden)

    Dombre Emmanuel

    2013-01-01

    Full Text Available We apply in this paper a geometrical shape optimization method for the design of the core of a SFR (Sodium-cooled Fast Reactor in order to minimize a thermal counter-reaction known as the sodium void effect. In this kind of reactors, by increasing the temperature, the core may become liable to a strong increase of reactivity, a key-parameter governing the chain-reaction at quasi-static states. We first use the one group energy diffusion model and give the generalization to the two groups energy equation. We then give some numerical results in the case of the one group energy equation. Note that the application of our method leads to some designs whose interfaces can be parametrized by very smooth curves which can stand very far from realistic designs. We don’t explain here the method that it would be possible to use for recovering an operational design but there exists several penalization methods (see [2] that could be employed to this end. On applique dans cet article une méthode d’optimisation géométrique dans le cadre de la conception d’un cœur de réacteur SFR (Sodium-cooled Fast Reactor, i.e. réacteur à neutron rapide refroidi au sodium dans le but de minimiser une contre réaction thermique connue sous le nom d’effet de vidange sodium. Lorsqu’une augmentation de température survient, ce type de réacteur peut être sujet à une forte augmentation de réactivité, un paramètre clé dans le contrôle de la réaction en chaîne en régime quasi-statique. On a recours à l’équation de diffusion à un groupe puis on donne la généralisation du modèle d’optimisation pour l’équation de la diffusion à deux groupes d’énergie. On présente ensuite quelques résultats numériques obtenus dans le cas de l’équation à un groupe d’énergie. On note que l’application de cette méthode conduit à des designs de cœur présentant des interfaces très régulières qui sont loin d’un design de cœur faisable sur le

  6. Passive compact molten salt reactor (PCMSR), modular thermal breeder reactor with totally passive safety system

    Energy Technology Data Exchange (ETDEWEB)

    Harto, Andang Widi [Engineering Physics Department, Faculty of Engineering, Gadjah Mada University (Indonesia)

    2012-06-06

    Design Study Passive Compact Molten Salt Reactor (PCMSR) with totally passive safety system has been performed. The term of Compact in the PCMSR name means that the reactor system is designed to have relatively small volume per unit power output by using modular and integral concept. In term of modular, the reactor system consists of three modules, i.e. reactor module, turbine module and fuel management module. The reactor module is an integral design that consists of reactor, primary and intermediate heat exchangers and passive post shutdown cooling system. The turbine module is an integral design of a multi heating, multi cooling, regenerative gas turbine. The fuel management module consists of all equipments related to fuel preparation, fuel reprocessing and radioactive handling. The preliminary calculations show that the PCMSR has negative temperature and void reactivity coefficient, passive shutdown characteristic related to fuel pump failure and possibility of using natural circulation for post shutdown cooling system.

  7. Advanced research reactor fuel development

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Chang Kyu; Pak, H. D.; Kim, K. H. [and others

    2000-05-01

    The fabrication technology of the U{sub 3}Si fuel dispersed in aluminum for the localization of HANARO driver fuel has been launches. The increase of production yield of LEU metal, the establishment of measurement method of homogeneity, and electron beam welding process were performed. Irradiation test under normal operation condition, had been carried out and any clues of the fuel assembly breakdown was not detected. The 2nd test fuel assembly has been irradiated at HANARO reactor since 17th June 1999. The quality assurance system has been re-established and the eddy current test technique has been developed. The irradiation test for U{sub 3}Si{sub 2} dispersed fuels at HANARO reactor has been carried out in order to compare the in-pile performance of between the two types of U{sub 3}Si{sub 2} fuels, prepared by both the atomization and comminution processes. KAERI has also conducted all safety-related works such as the design and the fabrication of irradiation rig, the analysis of irradiation behavior, thermal hydraulic characteristics, stress analysis for irradiation rig, and thermal analysis fuel plate, for the mini-plate prepared by international research cooperation being irradiated safely at HANARO. Pressure drop test, vibration test and endurance test were performed. The characterization on powders of U-(5.4 {approx} 10 wt%) Mo alloy depending on Mo content prepared by rotating disk centrifugal atomization process was carried out in order to investigate the phase stability of the atomized U-Mo alloy system. The {gamma}-U phase stability and the thermal compatibility of atomized U-16at.%Mo and U-14at.%Mo-2at.%X(: Ru, Os) dispersion fuel meats at an elevated temperature have been investigated. The volume increases of U-Mo compatibility specimens were almost the same as or smaller than those of U{sub 3}Si{sub 2}. However the atomized alloy fuel exhibited a better irradiation performance than the comminuted alloy. The RERTR-3 irradiation test of nano

  8. Hydrodynamics of multi-phase packed bed micro-reactors

    NARCIS (Netherlands)

    Márquez Luzardo, N.M.

    2010-01-01

    Why to use packed bed micro-reactors for catalyst testing? Miniaturized packed bed reactors have a large surface-to-volume ratio at the reactor and particle level that favors the heat- and mass-transfer processes at all scales (intra-particle, inter-phase and inter-particle or reactor level). If the

  9. Progress of China Experimental Fast Reactor in 2011

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    1 Background Fast reactor is the reactor which realized the chain fission with fast neutron.As an optional type of generation Ⅳ reactor,fast reactor has three characters:1) It can change 238U to 239Pu and raise the uranium resource utilization

  10. Uncertainties in the Anti-neutrino Production at Nuclear Reactors

    OpenAIRE

    Djurcic, Z.(Argonne National Laboratory, Argonne, Illinois, 60439, U.S.A.); Detwiler, J. A.; Piepke, A.; Foster Jr., V. R.; Miller, L.; Gratta, G.

    2008-01-01

    Anti-neutrino emission rates from nuclear reactors are determined from thermal power measurements and fission rate calculations. The uncertainties in these quantities for commercial power plants and their impact on the calculated interaction rates in electron anti-neutrino detectors is examined. We discuss reactor-to-reactor correlations between the leading uncertainties and their relevance to reactor anti-neutrino experiments.

  11. Souci du social et action publique sur mesure

    Directory of Open Access Journals (Sweden)

    Bertrand Ravon

    2008-10-01

    Full Text Available L’engagement dans la lutte contre les problèmes sociaux s’est transformé. Avec l’individualisation et la territorialisation du traitement public des problèmes sociaux, se pose de plus en plus nettement la question d’une action publique de proximité, intersubjective. Mais plutôt que de renvoyer immédiatement les raisons de cette action publique sur mesure à une critique de la psychologisation des rapports sociaux ou du déclin des institutions, il s’agit de l’analyser comme une expérience publique, avec son lot d’actions et d’affects, de convictions et d’inquiétudes, de ressources et de préoccupations. La notion de souci s’impose alors pour tenir ce double mouvement de l’engagement, entre agir et subir, des épreuves qui nous conduisent dans l’action aux attentes qui nous y maintiennent. À partir de plusieurs exemples de formation de problèmes sociaux, l’article décline alors le souci des acteurs dans deux directions. D’une part, le souci de soi est analysé comme un engagement public au sens d’un travail d’orientation de soi dans un monde incertain via la reprise d’expériences sociales négatives. D’autre part, le souci commun est envisagé comme une « communauté de charge », c’est-à-dire comme un collectif d’action publique fondé non pas à partir de propriétés communes mais à partir d’affects partagés.“Concern” in the social sphere and public action adapted to the client: singular and critical public experience of social problemsCommitment in the struggle against social problems has changed. Along with the individualisation and territorial decentralisation of the public treatment of social problems, the question of very local and intersubjective public action has come more and more into focus. But rather than immediately relegating the reasons for this tailor-made version of social action to a critique of the increasing influence of psychological methods in social relations

  12. Ex-vessel Steam Explosion Analysis for Pressurized Water Reactor and Boiling Water Reactor

    OpenAIRE

    Matjaž Leskovar; Mitja Uršič

    2016-01-01

    A steam explosion may occur during a severe accident, when the molten core comes into contact with water. The pressurized water reactor and boiling water reactor ex-vessel steam explosion study, which was carried out with the multicomponent three-dimensional Eulerian fuel–coolant interaction code under the conditions of the Organisation for Economic Co-operation and Development (OECD) Steam Explosion Resolution for Nuclear Applications project reactor exercise, is presented and discussed. In ...

  13. Optimization of a sequence of reactors

    DEFF Research Database (Denmark)

    Vidal, Rene Victor Valqui

    1991-01-01

    Concerns the optimal production of sulphuric acid in a sequence of reactors. Using a suitable approximation to the objective function, this problem can easily be solved using the maximum principle. A numerical example documents the applicability of the suggested approach...

  14. The Bifurcation Behavior of CO Coupling Reactor

    Institute of Scientific and Technical Information of China (English)

    徐艳; 马新宾; 许根慧

    2005-01-01

    The bifurcation behavior of the CO coupling reactor was examined based on the one-dimensional pseudohomogeneous axial dispersion dynamic model. The method of finite difference was used for solving the boundary value problem; the continuation technique and the direct method were applied to determine the bifurcation diagram.The effects of dimensionless adiabatic temperature rise, Damkoehler number, activation energy, heat transfer coefficient and feed ratio on the bifurcation behavior were investigated. It was shown that there existed static bifurcation and the oscillations did not occur in the reactor. The result also revealed that the reactor exhibited at most 1-3-1 multiplilicity patterns within the range of practical possible parameters and the measures, such as weakening the axial dispersion of reactor, enhancing heat transfer, decreasing the concentration of ethyl nitrite, were efficient for avoiding the possible risk of multiple steady states.

  15. Heat pipe reactors for space power applications

    Science.gov (United States)

    Koenig, D. R.; Ranken, W. A.; Salmi, E. W.

    1977-01-01

    A family of heat pipe reactors design concepts has been developed to provide heat to a variety of electrical conversion systems. Three power plants are described that span the power range 1-500 kWe and operate in the temperature range 1200-1700 K. The reactors are fast, compact, heat-pipe cooled, high-temperature nuclear reactors fueled with fully enriched refractory fuels, UC-ZrC or UO2. Each fuel element is cooled by an axially located molybdenum heat pipe containing either sodium or lithium vapor. Virtues of the reactor designs are the avoidance of single-point failure mechanisms, the relatively high operating temperature, and the expected long lifetimes of the fuel element components.

  16. Reactor Antineutrinos: From Confusion to Clarity

    Science.gov (United States)

    Dwyer, Dan

    2016-09-01

    Antineutrinos emitted by nuclear reactors have been a powerful tool for particle physics, demonstrating the existence of these weakly-interacting particles as well as their flavor oscillation. Despite these successes, our understanding of the total flux and energy spectra of reactor antineutrinos has been fraught with problems. I will give a brief overview of the unexpected developments in this field, and discuss upcoming measurements of antineutrinos, beta decays, and nuclear fission which are relevant to these questions. These measurements are expected to clarify many currently murky issues, including the hypothetical oscillation of reactor antineutrinos to sterile states. The results should also provide a unique perspective into the nuclear physics of fission reactors. DOE OHEP DE-AC02-05CH11231.

  17. Chemical reactor modeling multiphase reactive flows

    CERN Document Server

    Jakobsen, Hugo A

    2014-01-01

    Chemical Reactor Modeling closes the gap between Chemical Reaction Engineering and Fluid Mechanics.  The second edition consists of two volumes: Volume 1: Fundamentals. Volume 2: Chemical Engineering Applications In volume 1 most of the fundamental theory is presented. A few numerical model simulation application examples are given to elucidate the link between theory and applications. In volume 2 the chemical reactor equipment to be modeled are described. Several engineering models are introduced and discussed. A survey of the frequently used numerical methods, algorithms and schemes is provided. A few practical engineering applications of the modeling tools are presented and discussed. The working principles of several experimental techniques employed in order to get data for model validation are outlined. The monograph is based on lectures regularly taught in the fourth and fifth years graduate courses in transport phenomena and chemical reactor modeling, and in a post graduate course in modern reactor m...

  18. µ-reactors for Heterogeneous Catalysis

    DEFF Research Database (Denmark)

    Jensen, Robert

    catalyst surface area by reacting off an adsorbed layer of oxygen with CO. This procedure can be performed at temperatures low enough that sintering of Pt nanoparticles is not an issue. Some results from the reactors are presented. In particular an unexpected oscillation phenomenon of CO-oxidation on Pt...... nanoparticles are presented in detail. The sensitivity of the reactors are currently being investigated with CO oxidation on Pt thin films as a test reaction, and the results so far are presented. We have at this point shown that we are able to reach full conversion with a catalyst area of 38 µm2 with a turn......This thesis is the summary of my work on the µ-reactor platform. The concept of µ-reactors is presented and some of the experimental challenges are outlined. The various experimental issues regarding the platform are discussed and the actual implementation of three generations of the setup...

  19. Corrosion Minimization for Research Reactor Fuel

    Energy Technology Data Exchange (ETDEWEB)

    Eric Shaber; Gerard Hofman

    2005-06-01

    Existing university research reactors are being converted to use low-enriched uranium fue to eliminate the use of highly-enriched uranium. These conversions require increases in fuel loading that will result in the use of elements with more fuel plates, resulting in a net decrease in the water annulus between fuel plates. The proposed decrease in the water annulus raises questions about the requirements and stability of the surface hydroxide on the aluminum fuel cladding and the potential for runaway corrosion resulting in fuel over-temperature incidents. The Nuclear Regulatory Commission (NRC), as regulator for these university reactors, must ensure that proposed fuel modifications will not result in any increased risk or hazard to the reactor operators or the public. This document reviews the characteristics and behavior of aluminum hydroxides, analyzes the drivers for fuel plate corrosion, reviews relevant historical incidents, and provides recommendations on fuel design, surface treatment, and reactor operational practices to avoid corrosion issues.

  20. Interactions of Pellet with Reactor Relevant Plasma

    Institute of Scientific and Technical Information of China (English)

    PENGLilin; DENGBaiquan; YANJiancheng

    2003-01-01

    Extended algorithm has been developed for ablation rate calculations of Li, Be, B impurity pellets and five combinations of solid isotopic hydrogenic H2, HD, D2, DT, T2 pellets. Numerical calculations have been performed for reactor relevant plasma.

  1. Autonomous Control of Space Nuclear Reactors Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Nuclear reactors to support future lunar and Mars robotic and manned missions impose new and innovative technological requirements for their control and protection...

  2. Advanced Test Reactor National Scientific User Facility

    Energy Technology Data Exchange (ETDEWEB)

    Frances M. Marshall; Jeff Benson; Mary Catherine Thelen

    2011-08-01

    The Advanced Test Reactor (ATR), at the Idaho National Laboratory (INL), is a large test reactor for providing the capability for studying the effects of intense neutron and gamma radiation on reactor materials and fuels. The ATR is a pressurized, light-water, high flux test reactor with a maximum operating power of 250 MWth. The INL also has several hot cells and other laboratories in which irradiated material can be examined to study material irradiation effects. In 2007 the US Department of Energy (DOE) designated the ATR as a National Scientific User Facility (NSUF) to facilitate greater access to the ATR and the associated INL laboratories for material testing research by a broader user community. This paper highlights the ATR NSUF research program and the associated educational initiatives.

  3. EMERGING TECHNOLOGY BULLETIN: SPOUTED BED REACTOR

    Science.gov (United States)

    The Spouted Bed Reactor (SBR) technology utilizes the unique attributes of the "spouting " fluidization regime, which can provide heat transfer rates comparable to traditional fluid beds, while providing robust circulation of highly heterogeneous solids, concurrent with very agg...

  4. Molten salt reactors - safety options galore

    Energy Technology Data Exchange (ETDEWEB)

    Gat, U. [Oak Ridge National Lab., TN (United States); Dodds, H.L. [Univ. of Tennessee, Knoxville, TN (United States)

    1997-03-01

    Safety features and attributes of molten salt reactors (MSR) are described. The unique features of fluid fuel reactors of on-line continuous processing and the ability for so-called external cooling result in simple and safe designs with low excess reactivity, low fission product inventory, and small source term. These, in turn, make a criticality accident unlikely and reduce the severity of a loss of coolant to where they are no longer severe accidents. A melt down is not an accident for a reactor that uses molten fuel. The molten salts are stable, non-reactive and efficient heat transfer media that operate at high temperatures at low pressures and are highly compatible with selected structural materials. All these features reduce the accident plethora. Freeze valves can be used for added safety. An ultimate safe reactor (U.S.R) is described with safety features that are passive, inherent and non-tamperable (PINT).

  5. Steady State Analysis of Small Molten Salt Reactor : Effect of Fuel Salt Flow on Reactor Characteristics

    OpenAIRE

    Yamamoto, Takahisa; MITACHI, Koshi; Suzuki, Takashi

    2005-01-01

    The Molten Salt Reactor (MSR) is a thermal neutron reactor with graphite moderation and operates on the thorium-uranium fuel cycle. The feature of the MSR is that fuel salt flows inside the reactor during the nuclear fission reaction. In the previous study, the authors developed numerical model with which to simulate the effects of fuel salt flow on the reactor characteristics. In this study, we apply the model to the steady-state analysis of a small MSR system and estimate the effects of fue...

  6. Development of technology for next generation reactor - Development of next generation reactor in Korea -

    Energy Technology Data Exchange (ETDEWEB)

    Park, Jong Kyun; Chang, Moon Heuy; Hwang, Yung Dong [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of)] [and others

    1993-09-01

    The project, development of next generation reactor, aims overall related technology development and obtainment of related license in 2001. The development direction is to determine the reactor type and to build up the design concept in 1994. For development trend analysis of foreign next generation reactor, level-1 PSA, fuel cycle analysis and computer code development are performed on System 80+ and AP 600. Especially for design characteristics analysis and volume upgrade of AP 600, nuclear fuel and reactor core design analysis, coolant circuit design analysis, mechanical structure design analysis and safety analysis etc. are performed. (Author).

  7. A fast and flexible reactor physics model for simulating neutron spectra and depletion in fast reactors

    Science.gov (United States)

    Recktenwald, Geoff; Deinert, Mark

    2010-03-01

    Determining the time dependent concentration of isotopes within a nuclear reactor core is central to the analysis of nuclear fuel cycles. We present a fast, flexible tool for determining the time dependent neutron spectrum within fast reactors. The code (VBUDS: visualization, burnup, depletion and spectra) uses a two region, multigroup collision probability model to simulate the energy dependent neutron flux and tracks the buildup and burnout of 24 actinides, as well as fission products. While originally developed for LWR simulations, the model is shown to produce fast reactor spectra that show high degree of fidelity to available fast reactor benchmarks.

  8. Developments and Tendencies in Fission Reactor Concepts

    Science.gov (United States)

    Adamov, E. O.; Fuji-Ie, Y.

    This chapter describes, in two parts, new-generation nuclear energy systems that are required to be in harmony with nature and to make full use of nuclear resources. The issues of transmutation and containment of radioactive waste will also be addressed. After a short introduction to the first part, Sect. 58.1.2 will detail the requirements these systems must satisfy on the basic premise of peaceful use of nuclear energy. The expected designs themselves are described in Sect. 58.1.3. The subsequent sections discuss various types of advanced reactor systems. Section 58.1.4 deals with the light water reactor (LWR) whose performance is still expected to improve, which would extend its application in the future. The supercritical-water-cooled reactor (SCWR) will also be shortly discussed. Section 58.1.5 is mainly on the high temperature gas-cooled reactor (HTGR), which offers efficient and multipurpose use of nuclear energy. The gas-cooled fast reactor (GFR) is also included. Section 58.1.6 focuses on the sodium-cooled fast reactor (SFR) as a promising concept for advanced nuclear reactors, which may help both to achieve expansion of energy sources and environmental protection thus contributing to the sustainable development of mankind. The molten-salt reactor (MSR) is shortly described in Sect. 58.1.7. The second part of the chapter deals with reactor systems of a new generation, which are now found at the research and development (R&D) stage and in the medium term of 20-30 years can shape up as reliable, economically efficient, and environmentally friendly energy sources. They are viewed as technologies of cardinal importance, capable of resolving the problems of fuel resources, minimizing the quantities of generated radioactive waste and the environmental impacts, and strengthening the regime of nonproliferation of the materials suitable for nuclear weapons production. Particular attention has been given to naturally safe fast reactors with a closed fuel cycle (CFC

  9. A comparison of radioactive waste from first generation fusion reactors and fast fission reactors with actinide recycling

    Energy Technology Data Exchange (ETDEWEB)

    Koch, M.; Kazimi, M.S.

    1991-04-01

    Limitations of the fission fuel resources will presumably mandate the replacement of thermal fission reactors by fast fission reactors that operate on a self-sufficient closed fuel cycle. This replacement might take place within the next one hundred years, so the direct competitors of fusion reactors will be fission reactors of the latter rather than the former type. Also, fast fission reactors, in contrast to thermal fission reactors, have the potential for transmuting long-lived actinides into short-lived fission products. The associated reduction of the long-term activation of radioactive waste due to actinides makes the comparison of radioactive waste from fast fission reactors to that from fusion reactors more rewarding than the comparison of radioactive waste from thermal fission reactors to that from fusion reactors. Radioactive waste from an experimental and a commercial fast fission reactor and an experimental and a commercial fusion reactor has been characterized. The fast fission reactors chosen for this study were the Experimental Breeder Reactor 2 and the Integral Fast Reactor. The fusion reactors chosen for this study were the International Thermonuclear Experimental Reactor and a Reduced Activation Ferrite Helium Tokamak. The comparison of radioactive waste parameters shows that radioactive waste from the experimental fast fission reactor may be less hazardous than that from the experimental fusion reactor. Inclusion of the actinides would reverse this conclusion only in the long-term. Radioactive waste from the commercial fusion reactor may always be less hazardous than that from the commercial fast fission reactor, irrespective of the inclusion or exclusion of the actinides. The fusion waste would even be far less hazardous, if advanced structural materials, like silicon carbide or vanadium alloy, were employed.

  10. Environmental Information Document: L-reactor reactivation

    Energy Technology Data Exchange (ETDEWEB)

    Mackey, H.E. Jr. (comp.)

    1982-04-01

    Purpose of this Environmental Information Document is to provide background for assessing environmental impacts associated with the renovation, restartup, and operation of L Reactor at the Savannah River Plant (SRP). SRP is a major US Department of Energy installation for the production of nuclear materials for national defense. The purpose of the restart of L Reactor is to increase the production of nuclear weapons materials, such as plutonium and tritium, to meet projected needs in the nuclear weapons program.

  11. Oscillation Parameters with forthcoming Reactor Neutrino Experiments

    CERN Document Server

    Lasserre, Thierry

    2010-01-01

    I review the status of the forthcoming reactor neutrino experiments that toe the cutting edge of neutrino oscillation research. Kilometer baseline oscillation experiments (Double Chooz, Daya Bay, and Reno) will soon play a relevant role providing clean information on the last undetermined neutrino mixing angle !13. A 50-70 km baseline reactor neutrino experiment could later provide the best sensitivity to the !12 mixing angle.

  12. Advanced Reactors Transition Program Resource Loaded Schedule

    Energy Technology Data Exchange (ETDEWEB)

    GANTT, D.A.

    2000-01-12

    The Advanced Reactors Transition (ART) Resource Loaded Schedule (RLS) provides a cost and schedule baseline for managing the project elements within the ART Program. The Fast Flux Test Facility (FETF) activities are delineated through the end of FY 2000, assuming continued standby. The Nuclear Energy (NE) Legacies and Plutonium Recycle Test Reactor (PRTR) activities are delineated through the end of the deactivation process. This revision reflects the 19 Oct 1999 baseline.

  13. Advanced Reactors Transition Program Resource Loaded Schedule

    Energy Technology Data Exchange (ETDEWEB)

    BOWEN, W.W.

    1999-11-08

    The Advanced Reactors Transition (ART) Resource Loaded Schedule (RLS) provides a cost and schedule baseline for managing the project elements within the ART Program. The Fast Flux Test Facility (FFTF) activities are delineated through the end of FY 2000, assuming continued standby. The Nuclear Energy (NE) Legacies and Plutonium Recycle Test Reactor (PRTR) activities are delineated through the end of the deactivation process. This document reflects the 1 Oct 1999 baseline.

  14. The Daya Bay Reactor Neutrino Experiment

    Institute of Scientific and Technical Information of China (English)

    2012-01-01

    On Aug.15, 201l, a new large-scale scientific facility in China, Daya Bay Reactor Neutrino Experiment, started to operate. It is located in Daya Bay Nuclear Power Plant in Guangdong Province, around 50kin to both Hong Kong and Shenzhen City. The main scientific goal is to precisely determine the neutrino mixing angle 013 by detecting neutrinos from the reactors at different distances.

  15. Design of an Organic Simplified Nuclear Reactor

    OpenAIRE

    Koroush Shirvan; Eric Forrest

    2016-01-01

    Numerous advanced reactor concepts have been proposed to replace light water reactors ever since their establishment as the dominant technology for nuclear energy production. While most designs seek to improve cost competitiveness and safety, the implausibility of doing so with affordable materials or existing nuclear fuel infrastructure reduces the possibility of near-term deployment, especially in developing countries. The organic nuclear concept, first explored in the 1950s, offers an attr...

  16. Strengthening IAEA Safeguards for Research Reactors

    Energy Technology Data Exchange (ETDEWEB)

    Reid, Bruce D. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Anzelon, George A. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Budlong-Sylvester, Kory [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-09-01

    During their December 10-11, 2013, workshop in Grenoble France, which focused on the history and future of safeguarding research reactors, the United States, France and the United Kingdom (UK) agreed to conduct a joint study exploring ways to strengthen the IAEA’s safeguards approach for declared research reactors. This decision was prompted by concerns about: 1) historical cases of non-compliance involving misuse (including the use of non-nuclear materials for production of neutron generators for weapons) and diversion that were discovered, in many cases, long after the violations took place and as part of broader pattern of undeclared activities in half a dozen countries; 2) the fact that, under the Safeguards Criteria, the IAEA inspects some reactors (e.g., those with power levels under 25 MWt) less than once per year; 3) the long-standing precedent of States using heavy water research reactors (HWRR) to produce plutonium for weapons programs; 4) the use of HEU fuel in some research reactors; and 5) various technical characteristics common to some types of research reactors that could provide an opportunity for potential proliferators to misuse the facility or divert material with low probability of detection by the IAEA. In some research reactors, for example, such characteristics include rapid on-line refueling, and a core design with room for such a large number of assemblies or targets that it is difficult to detect diversion or undeclared irradiation. In addition, infrastructure associated with research reactors, such as hot cells, where plutonium could be separated, could pose a safeguards challenge because, in some cases, they are not declared (because they are not located in the facility or because nuclear materials are not foreseen to be processed inside) and may not be accessible to inspectors in States without an Additional Protocol in force.

  17. Current status of fast reactor physics

    Energy Technology Data Exchange (ETDEWEB)

    Hummel, H.H.

    1979-01-01

    The subject of calculation of reactivity coefficients for fast reactors is developed, starting with a discussion of the status of relevant nuclear data and proceeding to the subjects of group cross section generation and of methods of obtaining reactivity coefficients from group cross sections. Reactivity coefficients measured in critical experiments are compared with calculated values. Dependence of reactivity coefficients on reactor design is discussed. Finally, results of the recent international comparison of calculated reactivity coefficients are presented.

  18. Automatic safety rod for reactors. [LMFBR

    Science.gov (United States)

    Germer, J.H.

    1982-03-23

    An automatic safety rod for a nuclear reactor containing neutron absorbing material and designed to be inserted into a reactor core after a loss-of-flow. Actuation is based upon either a sudden decrease in core pressure drop or the pressure drop decreases below a predetermined minimum value. The automatic control rod includes a pressure regulating device whereby a controlled decrease in operating pressure due to reduced coolant flow does not cause the rod to drop into the core.

  19. Monitoring and control of anaerobic reactors

    DEFF Research Database (Denmark)

    Pind, Peter Frode; Angelidaki, Irini; Ahring, Birgitte Kiær;

    2003-01-01

    control approaches that have been used are comprehensively described. These include simple and adaptive controllers, as well as more recent developments such as fuzzy controllers, knowledge-based controllers and controllers based on neural networks.......The current status in monitoring and control of anaerobic reactors is reviewed. The influence of reactor design and waste composition on the possible monitoring and control schemes is examined. After defining the overall control structure, and possible control objectives, the possible process...

  20. COUPLED FAST-THERMAL POWER BREEDER REACTOR

    Science.gov (United States)

    Avery, R.

    1961-07-18

    A nuclear reactor having a region operating predominantly on fast neutrons and another region operating predominantly on slow neutrons is described. The fast region is a plutonium core and the slow region is a natural uranium blanket around the core. Both of these regions are free of moderator. A moderating reflector surrounds the uranium blanket. The moderating material and thickness of the reflector are selected so that fissions in the uranium blanket make a substantial contribution to the reactivity of the reactor.

  1. Short-baseline reactor neutrino oscillations

    Energy Technology Data Exchange (ETDEWEB)

    Mariani, C. [Department of Physics, Columbia University, New York, NY 10027 (United States)

    2011-08-15

    The neutrino mixing angle {theta}13 is currently a high-priority topic in the field of neutrino physics, with three different reactor neutrino experiments under way, searching for neutrino oscillations induced by this angle. A description of the reactor experiments searching for a non-zero value of {theta}13 is given, together with a discussion of their sensitivity within the next few years.

  2. Reactor Simulator Integration and Testing

    Science.gov (United States)

    Schoenfield, M. P.; Webster, K. L.; Pearson, J. B.

    2013-01-01

    As part of the Nuclear Systems Office Fission Surface Power Technology Demonstration Unit (TDU) project, a reactor simulator (RxSim) test loop was designed and built to perform integrated testing of the TDU components. In particular, the objectives of RxSim testing were to verify the operation of the core simulator, the instrumentation and control system, and the ground support gas and vacuum test equipment. In addition, it was decided to include a thermal test of a cold trap purification design and a pump performance test at pump voltages up to 150 V because the targeted mass flow rate of 1.75 kg/s was not obtained in the RxSim at the originally constrained voltage of 120 V. This Technical Memorandum summarizes RxSim testing. The gas and vacuum ground support test equipment performed effectively in NaK fill, loop pressurization, and NaK drain operations. The instrumentation and control system effectively controlled loop temperature and flow rates or pump voltage to targeted settings. The cold trap design was able to obtain the targeted cold temperature of 480 K. An outlet temperature of 636 K was obtained, which was lower than the predicted 750 K but 156 K higher than the cold temperature, indicating the design provided some heat regeneration. The annular linear induction pump tested was able to produce a maximum flow rate of 1.53 kg/s at 800 K when operated at 150 V and 53 Hz.

  3. Solid oxide electrochemical reactor science.

    Energy Technology Data Exchange (ETDEWEB)

    Sullivan, Neal P. (Colorado School of Mines, Golden, CO); Stechel, Ellen Beth; Moyer, Connor J. (Colorado School of Mines, Golden, CO); Ambrosini, Andrea; Key, Robert J. (Colorado School of Mines, Golden, CO)

    2010-09-01

    Solid-oxide electrochemical cells are an exciting new technology. Development of solid-oxide cells (SOCs) has advanced considerable in recent years and continues to progress rapidly. This thesis studies several aspects of SOCs and contributes useful information to their continued development. This LDRD involved a collaboration between Sandia and the Colorado School of Mines (CSM) ins solid-oxide electrochemical reactors targeted at solid oxide electrolyzer cells (SOEC), which are the reverse of solid-oxide fuel cells (SOFC). SOECs complement Sandia's efforts in thermochemical production of alternative fuels. An SOEC technology would co-electrolyze carbon dioxide (CO{sub 2}) with steam at temperatures around 800 C to form synthesis gas (H{sub 2} and CO), which forms the building blocks for a petrochemical substitutes that can be used to power vehicles or in distributed energy platforms. The effort described here concentrates on research concerning catalytic chemistry, charge-transfer chemistry, and optimal cell-architecture. technical scope included computational modeling, materials development, and experimental evaluation. The project engaged the Colorado Fuel Cell Center at CSM through the support of a graduate student (Connor Moyer) at CSM and his advisors (Profs. Robert Kee and Neal Sullivan) in collaboration with Sandia.

  4. Thermal-hydraulic interfacing code modules for CANDU reactors

    Energy Technology Data Exchange (ETDEWEB)

    Liu, W.S.; Gold, M.; Sills, H. [Ontario Hydro Nuclear, Toronto (Canada)] [and others

    1997-07-01

    The approach for CANDU reactor safety analysis in Ontario Hydro Nuclear (OHN) and Atomic Energy of Canada Limited (AECL) is presented. Reflecting the unique characteristics of CANDU reactors, the procedure of coupling the thermal-hydraulics, reactor physics and fuel channel/element codes in the safety analysis is described. The experience generated in the Canadian nuclear industry may be useful to other types of reactors in the areas of reactor safety analysis.

  5. Development of computer simulator for coal liquefaction reactor

    Energy Technology Data Exchange (ETDEWEB)

    Yawata, T.; Kobayashi, M.; Ohi, S.; Itho, H.; Hiraide, M. [Nippon Oil Co., Ltd., Tokyo (Japan)

    1995-12-31

    The computer simulator for a coal liquefaction reactor is a useful engineering tool to analyse the data of such reactors. The authors applied this technique to a reactor in the NEDOL process to predict the performance of the reactor, and to assist in the design of a reactor for demonstration plant. The development program of the simulator and its utilization plan are discussed. 4 figs., 2 tabs.

  6. Optimally moderated nuclear fission reactor and fuel source therefor

    Science.gov (United States)

    Ougouag, Abderrafi M.; Terry, William K.; Gougar, Hans D.

    2008-07-22

    An improved nuclear fission reactor of the continuous fueling type involves determining an asymptotic equilibrium state for the nuclear fission reactor and providing the reactor with a moderator-to-fuel ratio that is optimally moderated for the asymptotic equilibrium state of the nuclear fission reactor; the fuel-to-moderator ratio allowing the nuclear fission reactor to be substantially continuously operated in an optimally moderated state.

  7. Atmospheric pollution in the area of Vitry-sur-Seine and Alfortville; Pollution atmospherique dans la zone de Vitry-sur-Seine et d'Alfortville

    Energy Technology Data Exchange (ETDEWEB)

    Mayet, P.

    1997-07-01

    The aim of this report, demanded by the environmental minister, is the present state and the evolution of the atmospheric pollution in the area of Vitry-sur-seine and Alfortville, near Paris. In the first part the report takes stock of the air quality to show a decrease in the pollution due to fixed sources. A special interest is given in a second part to exhaust gases from the main factory of the area: the EDF power plant. The report concludes on the decrease of the industrial air pollution, the increase of the traffic air pollution and asks for the public information. (A.L.B.)

  8. Les stratégies d'influence sur Internet : validation expérimentale sur le lobby antinucléaire

    OpenAIRE

    Romma, Natacha; Boutin, Eric

    2005-01-01

    Les entreprises doivent apprendre à faire face à des flux informationnels croissants ce qui les conduit à de nouvelles approches du management de l'information. Au-delà de la veille dite passive, toute stratégie gagnante repose dorénavant sur la vision proactive de l'environnement informationnel qui lie étroitement l'information et l'action. Dans ce contexte, les stratégies d'influence présentent un intérêt particulier en tant qu'outils offensifs de l'intelligence informationnelle. De façon d...

  9. Design options for a bunsen reactor.

    Energy Technology Data Exchange (ETDEWEB)

    Moore, Robert Charles

    2013-10-01

    This work is being performed for Matt Channon Consulting as part of the Sandia National Laboratories New Mexico Small Business Assistance Program (NMSBA). Matt Channon Consulting has requested Sandia's assistance in the design of a chemical Bunsen reactor for the reaction of SO2, I2 and H2O to produce H2SO4 and HI with a SO2 feed rate to the reactor of 50 kg/hour. Based on this value, an assumed reactor efficiency of 33%, and kinetic data from the literature, a plug flow reactor approximately 1%E2%80%9D diameter and and 12 inches long would be needed to meet the specification of the project. Because the Bunsen reaction is exothermic, heat in the amount of approximately 128,000 kJ/hr would need to be removed using a cooling jacket placed around the tubular reactor. The available literature information on Bunsen reactor design and operation, certain support equipment needed for process operation and a design that meet the specification of Matt Channon Consulting are presented.

  10. Decommissioning of the Salaspils Research Reactor

    Directory of Open Access Journals (Sweden)

    Abramenkovs Andris

    2011-01-01

    Full Text Available In May 1995, the Latvian government decided to shut down the Salaspils Research Reactor and to dispense with nuclear energy in the future. The reactor has been out of operation since July 1998. A conceptual study on the decommissioning of the Salaspils Research Reactor was drawn up by Noell-KRC-Energie- und Umwelttechnik GmbH in 1998-1999. On October 26th, 1999, the Latvian government decided to start the direct dismantling to “green-field” in 2001. The upgrading of the decommissioning and dismantling plan was carried out from 2003-2004, resulting in a change of the primary goal of decommissioning. Collecting and conditioning of “historical” radioactive wastes from different storages outside and inside the reactor hall became the primary goal. All radioactive materials (more than 96 tons were conditioned for disposal in concrete containers at the radioactive wastes depository “Radons” at the Baldone site. Protective and radiation measurement equipment of the personnel was upgraded significantly. All non-radioactive equipment and materials outside the reactor buildings were released for clearance and dismantled for reuse or conventional disposal. Contaminated materials from the reactor hall were collected and removed for clearance measurements on a weekly basis.

  11. MOX in reactors: present and future

    Energy Technology Data Exchange (ETDEWEB)

    Arslan, Marc; Gros, Jean Pierre [AREVA NC - 33 rue La Fayette, 75009 Paris (France); Niquille, Aurelie; Marincic, Alexis [AREVA NP - Tour AREVA, 1 Place Jean Millier 92084 Paris La Defense (France)

    2010-07-01

    In Europe, MOX fuel has been supplied by AREVA for more than 30 years, to 36 reactors: 21 in France, 10 in Germany, 3 in Switzerland, 2 in Belgium. For the present and future, recycling is compulsory in the frame of sustainable development of nuclear energy. By 2030 the overall volume of used fuel will reach about 400 000 t worldwide. Their plutonium and uranium content represents a huge resource of energy to recycle. That is the reason why, the European Utilities issued an EUR (European Utilities Requirement) demanding new builds reactors to be able of using MOX Fuel Assemblies in up to 50 % of the core. AREVA GEN3+ reactors, like EPR{sup TM} or ATMEA{sup TM} designed with MHI partnership, are designed to answer any utility need of MOX recycling. The example of the EPR{sup TM} reactor operated with 100 % MOX core optimized for MOX recycling will be presented. A standard EPR{sup TM} can be operated with 100 % MOX core using an advanced homogeneous MOX (single Pu content) with highly improved performances (burn-up and Cycle length). The adaptations needed and the main operating and safety reactor features will be presented. AREVA offers the utilities throughout the world, fuel supply (UO{sub 2}, ERU, MOX), and reactors designed with all the needed capability for recycling. For each country and each utility, an adapted global solution, competitive and non proliferant can be proposed. (authors)

  12. Moving hot cell for LMFBR type reactor

    Energy Technology Data Exchange (ETDEWEB)

    Kanbe, Mitsuru

    1994-09-16

    A moving hot cell for an LMFBR type reactor is made movable on a reactor operation floor between a position just above the reactor container and a position retreated therefrom. Further, it comprises an overhung portion which can incorporate a spent fuel just thereunder, and a crane for moving a fuel assembly between a spent fuel cask and a reactor container. Further, an opening/closing means having a shielding structure is disposed to the bottom portion and the overhung portion thereof, to provide a sealing structure, in which only the receiving port for the spent fuel cask faces to the inner side, and the cask itself is disposed at the outside. Upon exchange of fuels, the movable hot cell is placed just above the reactor to take out the spent fuels, so that a region contaminated with primary sodium is limited within the hot cell. On the other hand, upon maintenance and repair for equipments, the hot cell is moved, thereby enabling to provide a not contaminated reactor operation floor. (N.H.).

  13. Supply of enriched uranium for research reactors

    Energy Technology Data Exchange (ETDEWEB)

    Mueller, H. [NUKEM GmbH, Alzenau (Germany)

    1997-08-01

    Since the RERTR-meeting In Newport/USA in 1990 the author delivered a series of papers in connection with the fuel cycle for research reactors dealing with its front-end. In these papers the author underlined the need for unified specifications for enriched uranium metal suitable for the production of fuel elements and made proposals with regard to the re-use of in Europe reprocessed highly enriched uranium. With regard to the fuel cycle of research reactors the research reactor community was since 1989 more concentrating on the problems of its back-end since the USA stopped the acceptance of spent research reactor fuel on December 31, 1988. Now, since it is apparent that these back-end problem have been solved by AEA`s ability to reprocess and the preparedness of the USA to again accept physically spent research reactor fuel the author is focusing with this paper again on the front-end of the fuel cycle on the question whether there is at all a safe supply of low and high enriched uranium for research reactors in the future.

  14. A nanoliter-scale open chemical reactor.

    Science.gov (United States)

    Galas, Jean-Christophe; Haghiri-Gosnet, Anne-Marie; Estévez-Torres, André

    2013-02-01

    An open chemical reactor is a container that exchanges matter with the exterior. Well-mixed open chemical reactors, called continuous stirred tank reactors (CSTR), have been instrumental for investigating the dynamics of out-of-equilibrium chemical processes, such as oscillations, bistability, and chaos. Here, we introduce a microfluidic CSTR, called μCSTR, that reduces reagent consumption by six orders of magnitude. It consists of an annular reactor with four inlets and one outlet fabricated in PDMS using multi-layer soft lithography. A monolithic peristaltic pump feeds fresh reagents into the reactor through the inlets. After each injection the content of the reactor is continuously mixed with a second peristaltic pump. The efficiency of the μCSTR is experimentally characterized using a bromate, sulfite, ferrocyanide pH oscillator. Simulations accounting for the digital injection process are in agreement with experimental results. The low consumption of the μCSTR will be advantageous for investigating out-of-equilibrium dynamics of chemical processes involving biomolecules. These studies have been scarce so far because a miniaturized version of a CSTR was not available.

  15. Uncertainty quantification approaches for advanced reactor analyses.

    Energy Technology Data Exchange (ETDEWEB)

    Briggs, L. L.; Nuclear Engineering Division

    2009-03-24

    The original approach to nuclear reactor design or safety analyses was to make very conservative modeling assumptions so as to ensure meeting the required safety margins. Traditional regulation, as established by the U. S. Nuclear Regulatory Commission required conservatisms which have subsequently been shown to be excessive. The commission has therefore moved away from excessively conservative evaluations and has determined best-estimate calculations to be an acceptable alternative to conservative models, provided the best-estimate results are accompanied by an uncertainty evaluation which can demonstrate that, when a set of analysis cases which statistically account for uncertainties of all types are generated, there is a 95% probability that at least 95% of the cases meet the safety margins. To date, nearly all published work addressing uncertainty evaluations of nuclear power plant calculations has focused on light water reactors and on large-break loss-of-coolant accident (LBLOCA) analyses. However, there is nothing in the uncertainty evaluation methodologies that is limited to a specific type of reactor or to specific types of plant scenarios. These same methodologies can be equally well applied to analyses for high-temperature gas-cooled reactors and to liquid metal reactors, and they can be applied to steady-state calculations, operational transients, or severe accident scenarios. This report reviews and compares both statistical and deterministic uncertainty evaluation approaches. Recommendations are given for selection of an uncertainty methodology and for considerations to be factored into the process of evaluating uncertainties for advanced reactor best-estimate analyses.

  16. Antineutrino reactor safeguards - a case study

    CERN Document Server

    Christensen, Eric; Jaffke, Patrick

    2013-01-01

    Antineutrinos have been proposed as a means of reactor safeguards for more than 30 years and there has been impressive experimental progress in neutrino detection. In this paper we conduct, for the first time, a case study of the application of antineutrino safeguards to a real-world scenario - the North Korean nuclear crisis in 1994. We derive detection limits to a partial or full core discharge in 1989 based on actual IAEA safeguards access and find that two independent methods would have yielded positive evidence for a second core with very high confidence. To generalize our results, we provide detailed estimates for the sensitivity to the plutonium content of various types of reactors, including most types of plutonium production reactors, based on detailed reactor simulations. A key finding of this study is that a wide class of reactors with a thermal power of less than 0.1-1 GWth can be safeguarded achieving IAEA goals for quantitative sensitivity and timeliness with detectors right outside the reactor ...

  17. FBR and RBR particle bed space reactors

    Energy Technology Data Exchange (ETDEWEB)

    Powell, J.R.; Botts, T.E.

    1983-01-01

    Compact, high-performance nuclear reactor designs based on High-Temperature Gas Reactors (HTGRs) particulate fuel are investigated. The large surface area available with the small-diameter (approx. 500 microns) particulate fuel allows very high power densities (MW's/liter), small temperature differences between fuel and coolant (approx. 10/sup 0/K), high coolant-outlet temperatures (1500 to 3000/sup 0/K, depending on design), and fast reactor startup (approx. 2 to 3 seconds). Two reactor concepts are developed - the Fixed Bed Reactor (FBR), where the fuel particles are packed into a thin annular bed between two porous cylindrical drums, and the Rotating Bed Reactor (RBR), where the fuel particles are held inside a cold rotating (typically approx. 500 rpm) porous cylindrical drum. The FBR can operate steady-state in the closed-cycle He-cooled mode or in the open-cycle H/sub 2/-cooled mode. The RBR will operate only in the open-cycle H/sub 2/-cooled mode.

  18. Oradour-sur-Glane: On the emergence of a glocal site of memory in France

    Directory of Open Access Journals (Sweden)

    Léger, Eva

    2014-12-01

    Full Text Available Oradour-sur-Glane (France is the memorial site of a massacre perpetrated by the Second SS Panzer Division Das Reich on June 10th, 1944. It preserves the memory of the 642 people slaughtered there, including 18 Spanish refugees. In 1945, the French State, led by General de Gaulle, decided to preserve the ruins of Oradour-sur- Glane. Since then, a series of commemorative processes have ensued at the site, corresponding to different temporalities. Over time, this site of national memory has been linked both with European memory discourse and with the private memory of exiled Spaniards and, consequently, with the memory of the Spanish Civil War and Francoism. In this article, I analyze the different appropriations and interpretations of the site, focusing in particular on the memory of the exiles. To do so, I will look into the initiatives undertaken between 2008 and 2014, considering both the institutions and the associations related to Oradour-sur-Glane.Oradour-sur-Glane (Francia es el lugar de memoria de una masacre perpetrada por la segunda división blindada S.S. Das Reich el 10 de junio de 1944 que conserva el recuerdo de sus 642 supliciados, entre los cuales 18 españoles refugiados. En 1945, el Estado francés encabezado por el General de Gaulle decidió preservar las ruinas de Oradour-sur-Glane. Desde entonces, diferentes procesos conmemorativos, correspondientes a temporalidades destacadas, se han sucedido en el sitio. Con el tiempo, este lugar de memoria nacional, se ha vinculado tanto con un discurso de memoria europeo como con la memoria particular de los españoles exiliados y a través de ello con la memoria de la Guerra Civil española y del franquismo. En este estudio analizaré las diferentes apropiaciones e interpretaciones de este lugar, enfocándome especialmente en la memoria de los exiliados. Para esto, contemplaré las iniciativas que se han desarrollado entre los años 2008 y 2014, atendiendo tanto a las instituciones como a

  19. Technology, Safety and Costs of Decommissioning Nuclear Reactors At Multiple-Reactor Stations

    Energy Technology Data Exchange (ETDEWEB)

    Wittenbrock, N. G.

    1982-01-01

    Safety and cost information is developed for the conceptual decommissioning of large (1175-MWe) pressurized water reactors (PWRs) and large (1155-MWe) boiling water reactors {BWRs) at multiple-reactor stations. Three decommissioning alternatives are studied: DECON (immediate decontamination), SAFSTOR (safe storage followed by deferred decontamination), and ENTOMB (entombment). Safety and costs of decommissioning are estimated by determining the impact of probable features of multiple-reactor-station operation that are considered to be unavailable at a single-reactor station, and applying these estimated impacts to the decommissioning costs and radiation doses estimated in previous PWR and BWR decommissioning studies. The multiple-reactor-station features analyzed are: the use of interim onsite nuclear waste storage with later removal to an offsite nuclear waste disposal facility, the use of permanent onsite nuclear waste disposal, the dedication of the site to nuclear power generation, and the provision of centralized services. Five scenarios for decommissioning reactors at a multiple-reactor station are investigated. The number of reactors on a site is assumed to be either four or ten; nuclear waste disposal is varied between immediate offsite disposal, interim onsite storage, and immediate onsite disposal. It is assumed that the decommissioned reactors are not replaced in one scenario but are replaced in the other scenarios. Centralized service facilities are provided in two scenarios but are not provided in the other three. Decommissioning of a PWR or a BWR at a multiple-reactor station probably will be less costly and result in lower radiation doses than decommissioning an identical reactor at a single-reactor station. Regardless of whether the light water reactor being decommissioned is at a single- or multiple-reactor station: • the estimated occupational radiation dose for decommissioning an LWR is lowest for SAFSTOR and highest for DECON • the estimated

  20. Reactor performances and microbial communities of biogas reactors: effects of inoculum sources.

    Science.gov (United States)

    Han, Sheng; Liu, Yafeng; Zhang, Shicheng; Luo, Gang

    2016-01-01

    Anaerobic digestion is a very complex process that is mediated by various microorganisms, and the understanding of the microbial community assembly and its corresponding function is critical in order to better control the anaerobic process. The present study investigated the effect of different inocula on the microbial community assembly in biogas reactors treating cellulose with various inocula, and three parallel biogas reactors with the same inoculum were also operated in order to reveal the reproducibility of both microbial communities and functions of the biogas reactors. The results showed that the biogas production, volatile fatty acid (VFA) concentrations, and pH were different for the biogas reactors with different inocula, and different steady-state microbial community patterns were also obtained in different biogas reactors as reflected by Bray-Curtis similarity matrices and taxonomic classification. It indicated that inoculum played an important role in shaping the microbial communities of biogas reactor in the present study, and the microbial community assembly in biogas reactor did not follow the niche-based ecology theory. Furthermore, it was found that the microbial communities and reactor performances of parallel biogas reactors with the same inoculum were different, which could be explained by the neutral-based ecology theory and stochastic factors should played important roles in the microbial community assembly in the biogas reactors. The Bray-Curtis similarity matrices analysis suggested that inoculum affected more on the microbial community assembly compared to stochastic factors, since the samples with different inocula had lower similarity (10-20 %) compared to the samples from the parallel biogas reactors (30 %).