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Sample records for fluide primaire des

  1. Soins primaires des personnes victimes d’une lésion médullaire

    PubMed Central

    McColl, Mary Ann; Aiken, Alice; McColl, Alexander; Sakakibara, Brodie; Smith, Karen

    2012-01-01

    Résumé Objectif Effectuer une étude de la portée des données empiriques, entre 1980 et 2009, concernant les soins primaires aux adultes victimes d’une lésion médullaire (LME). Sources des données Une recension dans des revues révisées par des pairs de1980 à 2009 à l’aide de CINAHL, PubMed-MEDLINE, EMBASE, PsycINFO, Social Sciences Abstracts et Social Work Abstracts. Sélection des études La recherche électronique au moyen de mots-clés a permis de cerner 42 articles sur les soins primaires et les LME. Des critères d’inclusion ont servi à réduire la liste à un ensemble de 21 articles publiés en anglais qui portaient sur un échantillon de plus de 3 et présentaient une analyse empirique. Synthèse Environ 90 % des personnes atteintes d’une LME ont identifié leur médecin de famille comme étant leur docteur habituel; 63 % avaient un spécialiste des LME. Les personnes vivant à long terme avec une LME développent des rubriques complexes pour naviguer dans leurs systèmes de soins de santé personnels. Les données scientifiques ne sont pas unanimes quant à l’efficacité des programmes d’intervention directe pour le maintien de la santé et la prévention des complications à la suite d’une LME. Les données appuient cependant le suivi périodique par une équipe spécialisée et un bilan de santé annuel complet. La recherche fait valoir un fort degré d’uniformité dans l’identification des problèmes les plus courants soulevés par les personnes atteintes d’une LME en soins primaires, dont la plupart concernent l’incapacité, plus précisément les complications secondaires, comme la dysfonction intestinale ou vésicale et la douleur. Il existe aussi de bonnes données probantes à l’effet que de nombreux problèmes de santé généraux exigent de l’attention dans une telle population, comme les problèmes de la densité osseuse, la dépression et les questions entourant la santé sexuelle et la reproduction. Il y a

  2. Approche à l’endroit des blessures traumatiques à la main en soins primaires

    PubMed Central

    Cheung, Kevin; Hatchell, Alexandra; Thoma, Achilleas

    2013-01-01

    Résumé Objectif Passer en revue la prise en charge initiale des blessures traumatiques communes à la main que voient les médecins de soins primaires. Sources des données Nous avons examiné les données cliniques probantes et les ouvrages spécialisés récents cernés par des recherches dans la base de données électronique MEDLINE. Nous avons utilisé l’opinion d’experts pour compléter les recommandations dans les domaines où les données scientifiques étaient rares. Message principal Les médecins de soins primaires sont couramment appelés à prendre en charge des patients victimes de blessures traumatiques à la main. Dans le contexte d’un cas clinique, nous examinons l’évaluation, le diagnostic et la prise en charge initiale des traumatismes communs à la main. La présentation et la prise en charge des blessures au lit de l’ongle, des amputations de l’extrémité du doigt, des doigts en maillet, des fractures à la main, des lacérations de tendons, des morsures et de la ténosynovite infectieuse seront aussi discutées. Les principes de la prise en charge des blessures traumatiques à la main comportent la réduction et l’immobilisation des fractures, la prescription d’imagerie radiographique post-réduction, l’obtention d’un recouvrement par les tissus mous, la prévention et le traitement des infections et l’assurance d’une prophylaxie antitétanique. Conclusion Il est essentiel d’assurer une évaluation et une prise en charge appropriées des blessures traumatiques à la main pour prévenir une morbidité considérable à long terme dans une population autrement en santé. La reconnaissance sans délai des blessures qui nécessitent une demande de consultation urgente ou rapide auprès d’un chirurgien spécialiste de la main est également critique.

  3. Lignes directrices sur la prise en charge en soins primaires des céphalées chez l’adulte

    PubMed Central

    Becker, Werner J.; Findlay, Ted; Moga, Carmen; Scott, N. Ann; Harstall, Christa; Taenzer, Paul

    2015-01-01

    Résumé Objectif Accroître l’utilisation d’approches éclairées par des données probantes pour diagnostiquer, investiguer et traiter en soins primaires les céphalées des patients. Qualité des données Une recherche documentaire exhaustive a été effectuée pour trouver des lignes directrices et des révisions systématiques publiées entre janvier 2000 et mai 2011. La grille d’évaluation de la qualité des recommandations pour la pratique clinique AGREE a servi à l’analyse critique des lignes directrices. Les 6 guides de pratique clinique de la plus grande qualité ont servi de base dans le processus d’adaptation. Message principal Un groupe d’élaboration multidisciplinaire de professionnels des soins primaires ont formulé 91 recommandations précises à l’aide d’un processus consensuel. Les recommandations portent sur le diagnostic, l’investigation et la prise en charge de la migraine, de la céphalée de tension, de la céphalée due à une surmédication et de la céphalée vasculaire de Horton. Conclusion Un guide de pratique clinique adapté au contexte des soins de santé au Canada a été produit en suivant un processus d’adaptation de lignes directrices dans le but d’aider les professionnels de toutes les disciplines des soins primaires à dispenser des soins éclairés par des données probantes aux patients souffrant de céphalées.

  4. Lignes directrices sur l’aiguillage des cas soupçonnés de cancer colorectal par un médecin de famille ou autre professionnel des soins primaires

    PubMed Central

    Del Giudice, M. Elisabeth; Vella, Emily T.; Hey, Amanda; Simunovic, Marko; Harris, William; Levitt, Cheryl

    2014-01-01

    Résumé Objectif Ces lignes directrices ont pour but d’aider les médecins de famille et les autres professionnels des soins primaires à reconnaître les caractéristiques qui devraient susciter leurs soupçons quant à la présence d’un cancer colorectal (CCR) chez leurs patients. Composition du comité Les membres du comité ont été choisis parmi les dirigeants régionaux des soins primaires au sein du Réseau provincial des soins primaires et de la lutte contre le cancer, les membres du Comité consultatif sur le dépistage du cancer colorectal de l’Ontario et les membres du Groupe sur le siège de la maladie, Cancer gastrointestinal, d’Action Cancer Ontario. Méthodes Ces lignes directrices sont le fruit d’une revue systématique et d’une synthèse des données probantes, ainsi que d’un examen formel par des intervenants canadiens pour valider la pertinence des recommandations. Rapport Des lignes directrices fondées sur des données probantes ont été élaborées pour améliorer la prise en charge des patients qui présentent des caractéristiques cliniques d’un CCR et ce, dans le contexte canadien. Conclusion Un équilibre judicieux entre une suspicion de CCR et le niveau de risque d’un tel cancer devrait favoriser une demande de consultation en temps opportun par les médecins de famille et les professionnels des soins primaires. Ces lignes directrices pourraient aussi orienter les décisions de demander une consultation à des programmes d’évaluation diagnostique du CCR.

  5. Prise en charge en soins primaires des troubles liés à l’usage d’alcool et de la consommation à risque

    PubMed Central

    Spithoff, Sheryl; Kahan, Meldon

    2015-01-01

    Résumé Objectif Fournir aux médecins de soins primaires de l’information et des conseils fondés sur des données probantes sur le dépistage et l’évaluation de la consommation d’alcool à risque et des troubles liés à l’usage d’alcool (TUA). Sources des données Nous avons effectué une recherche documentaire non systématique en utilisant des expressions de recherche portant sur les soins primaires, les TUA, la dépendance à l’alcool, l’abus d’alcool, l’usage abusif d’alcool, la consommation d’alcool néfaste pour la santé, ainsi que le dépistage, la détermination et l’évaluation dans le contexte des soins primaires. Principaux messages Les médecins de famille devraient faire passer un test validé de dépistage de l’abus d’alcool à tous les patients, au moins une fois par année. Dépister les patients qui se présentent avec des problèmes médicaux ou psychosociaux pouvant être reliés à l’usage d’alcool. Déterminer si les patients qui obtiennent des résultats positifs lors du dépistage sont des consommateurs d’alcool à risque ou s’ils ont des TUA. Si les patients ont des TUA, déterminer si les troubles sont légers, modérés ou sévères en utilisant les critères de la 5e édition du Manuel diagnostique et statistique des troubles mentaux. Communiquer le diagnostic aux patients et leur offrir de l’aide. Effectuer une évaluation plus approfondie des patients ayant des TUA. Procéder à un dépistage de la consommation d’autres substances, des troubles concomitants et des traumatismes. Déterminer s’il est nécessaire de rapporter le cas aux services de protection de l’enfance ou au ministère des Transports. Déterminer les besoins en matière de prise en charge médicale du sevrage alcoolique. Effectuer un bref examen physique et prescrire l’exécution de tests de laboratoire pour évaluer la formule sanguine complète et les taux de transaminases hépatiques, comprenant les

  6. Prise en charge en soins primaires des troubles liés à l’usage d’alcool et de la consommation à risque

    PubMed Central

    Spithoff, Sheryl; Kahan, Meldon

    2015-01-01

    Résumé Objectif Présenter aux médecins de soins primaires des renseignements et des conseils fondés sur des données probantes concernant la prise en charge de la consommation à risque et des troubles liés à l’usage d’alcool (TUA). Sources des données Nous avons entrepris une recherche documentaire non systématique à l’aide d’expressions de recherche en anglais, notamment primary care; screening, interventions, management et treatment; et at-risk drinking, alcohol use disorders, alcohol dependence et alcohol abuse; ainsi que des interventions spécifiques en médecine et en counseling pertinentes aux soins primaires. Principaux messages Dans le cas de patients ayant une consommation à risque ou un TUA, les médecins devraient offrir du counseling et, au besoin (p. ex. les patients dont le TUA est de modéré à grave), prescrire et connecter. Counseling : Offrir à tous les patients ayant une consommation à risque une brève séance de counseling et un suivi. Offrir à tous les patients ayant un TUA des séances de counseling et un suivi constant (fréquent et régulier). Prescrire : Offrir des médicaments (disulfiram, naltrexone, acamprosate) à tous les patients ayant un TUA de modéré à grave. Connecter : Encourager les patients souffrant d’un TUA à suivre des programmes de counseling de jour ou en résidence et d’adhérer à des groupes d’entraide. S’il est indiqué de le faire, demander une consultation pour le patient auprès d’un spécialiste en médecine des dépendances, de services concurrents en santé mentale et en toxicomanie ou une thérapie spécialisée pour traumatisme. Conclusion Les médecins de famille peuvent prendre en charge efficacement les patients qui ont une consommation à risque ou des TUA.

  7. Lignes directrices sur l’aiguillage des cas soupçonnés de cancer du poumon par un médecin de famille ou autre professionnel des soins primaires

    PubMed Central

    Del Giudice, M. Elisabeth; Young, Sheila-Mae; Vella, Emily T.; Ash, Marla; Bansal, Praveen; Robinson, Andrew; Skrastins, Roland; Ung, Yee; Zeldin, Robert; Levitt, Cheryl

    2014-01-01

    Résumé Objectif Les présentes lignes directrices visent à aider les médecins de famille et autres généralistes à reconnaître les manifestations cliniques devant éveiller les soupçons quant à la présence d’un cancer du poumon chez les patients. Composition du comité Les membres du comité ont été choisis parmi les leaders régionaux en soins primaires du Réseau provincial des soins primaires et de la lutte contre le cancer d’Action Cancer Ontario et parmi les membres du Groupe sur le siège de la maladie, Cancer du poumon d’Action Cancer Ontario. Méthodes Les présentes lignes directrices sont le fruit d’une revue systématique des données probantes, d’une synthèse des données et d’un examen externe formel effectué par des intervenants canadiens qui ont validé la pertinence des recommandations. Rapport Ces lignes directrices fondées sur des données probantes ont été formulées pour améliorer la prise en charge en contexte canadien des patients qui présentent des manifestations cliniques du cancer du poumon. Conclusion Le dépistage et l’aiguillage précoces des patients atteints de cancer du poumon pourraient en fin de compte aider à réduire les morbidités et mortalités liées au cancer. Ces lignes directrices pourraient aussi s’avérer utiles dans la mise sur pied de programmes de diagnostic du cancer du poumon et pour aider les décideurs à veiller à ce que les ressources appropriées soient en place.

  8. Regard pluriel sur l'enseignement et l'apprentissage des mathematiques a l'ecole primaire.

    ERIC Educational Resources Information Center

    Lopez, Lucie Mottier

    The texts gathered in this document come from work done in the framework of two postgraduate courses at the Faculte des Sciences de l'Education, Geneva: (1) "Learning: Meta-cognitive et socio-cognitive dimensions" course; and (2) "Didactical analysis of the interactions in class: Case study of mathematics at school" course. The problematics dealt…

  9. Prise de suppléments multivitaminiques pour la prévention primaire des anomalies congénitalies

    PubMed Central

    Morin, Pascale; Demers, Karine; Giguère, Christine; Tribble, Denise St-Cyr; Lane, Julie

    2007-01-01

    RÉSUMÉ OBJECTIF Déterminer si les recommandations véhiculées par les professionnels de la santé sur l’importance de l’acide folique encouragent les femmes susceptibles de procréer de prendre les suppléments d’acide folique. CONCEPTION Enquête. CONTEXTE Centre de santé et de services sociaux, Institut universitaire de gériatrie de Sherbrooke, à Sherbrooke, Qué. PARTICIPANTS 323 femmes francophones âgées entre 18 et 45 ans. PRINCIPALES MESURES DES RÉSULTATS La consommation de suppléments de vitamines et de minéraux au cours de la dernière année. Des analyses statistiques descriptives et bivariées et une modélisation par régression logistique ont été effectuées pour déterminer si l’association observée entre la recommandation d’un professionnel de la santé et la consommation de vitamines et de minéraux persistait après avoir tenu compte de l’effet des variables de contrôle (consultation de documentation, connaissances, sources d’information, perception, âge, scolarité, revenu, état matrimonial, intention de devenir enceinte). RÉSULTATS Environ 41% des femmes rapportent que leur médecin leur avait recommandé de consommer un supplément de vitamines et de minéraux. Après avoir ajusté toutes les variables dans le modèle, il est apparu que le fait de se faire recommander par un professionnel de la santé de prendre un supplément de vitamines et de minéraux était significativement associé à la consommation de vitamines et de minéraux par les femmes susceptibles de devenir enceintes. CONCLUSION Les professionnels peuvent améliorer la santé de la population par une pratique clinique préventive. Nous soulignons l’importance de soutenir ces derniers dans leurs efforts d’intégrer puis d’appliquer des connaissances scientifiques dans leur pratique. PMID:18077754

  10. Une modélisation de haut niveau des stratégies d'écriture motrice d'enfants en scolarité primaire : approche bayésienne

    NASA Astrophysics Data System (ADS)

    Zaarour, I.; El-Eter, B.; Leray, P.; Heutte, L.; Labiche, J.; Mellier, D.; Zoaeter, M.

    2005-05-01

    L'objectif de cette étude est de découvrir des stratégies d'écriture motrices des enfants en scolarité primaire en adoptant un modèle graphique probabiliste (réseaux bayésiens). Nous représentons une stratégie d'écriture par une variable cachée et nous construisons ainsi un modèle global hiérarchique pour pouvoir lier les stratégies locales aux stratégies globales et modéliser la dépendance probabiliste entre variables et stratégies. Ce modèle hiérarchique, appris à partir des données réelles, nous a permis de découvrir des stratégies consistantes et robustes. Ces résultats nous a permis de favoriser une modélisation temporelle et dynamique des stratégies d'écriture motrices indépendantes de l'âge scolaire.

  11. Mise à jour sur la prévention et le dépistage selon l’âge à l’intention des médecins de soins primaires canadiens

    PubMed Central

    Shimizu, Tawnya; Bouchard, Manon; Mavriplis, Cleo

    2016-01-01

    Résumé Objectif Faire la synthèse des meilleures lignes directrices fondées sur des données probantes concernant la prévention et le dépistage chez les adultes canadiens selon l’âge. Qualité des données Les recommandations du Groupe d’étude canadien sur les soins de santé préventifs représentent la source principale des renseignements et sont complétées par les recommandations pertinentes du Preventive Services Task Force des États-Unis lorsque celles du Groupe d’étude canadien étaient inaccessibles ou désuètes. Les guides de pratique des principales organisations nationales axées spécifiquement sur une maladie ou une spécialité ont aussi fait l’objet d’une révision pour prendre en compte les données factuelles les plus récentes. Message principal Les interventions de dépistage recommandées selon l’âge et le sexe sont présentées dans un tableau de synthèse où est mise en évidence la qualité des données à l’appui de ces recommandations. Un exemple de modèle à suivre dans les dossiers médicaux électroniques ou sur papier est aussi proposé. Conclusion Qu’il s’agisse d’une visite consacrée à la prévention ou d’une occasion saisie autrement de faire du counseling et du dépistage de prévention chez leurs patients, les médecins de soins primaires peuvent se servir de cette synthèse des recommandations fondées sur des données probantes pour maximiser leur efficience et prévenir d’importantes omissions ou des dépistages inutiles.

  12. Force dynamique des membranes fluides

    NASA Astrophysics Data System (ADS)

    Evans, Evan; Heinrich, Volkmar

    2003-03-01

    Rupturing fluid membrane vesicles with a steady ramp of micropipette suction yields a tension distribution that images the kinetic process of membrane failure. When plotted on a log scale of tension loading rate, the distribution peaks (membrane strengths) define a dynamic tension spectrum with distinct regimes that reflect passage of prominent energy barriers along the pathway to rupture. Demonstrated here by tests on giant PC lipid vesicles over loading rates from 0.06-60 mN/m/s, the stochastic process of rupture can be modelled as a causal sequence of two thermally-activated transitions where each transition governs membrane strength on separate scales of loading rate. Under fast ramps of tension, a steep linear regime appears in each spectrum at high strengths which implies that failure requires nucleation of a rare nanoscale defect. The slope and projected intercept yield defect size and spontaneous production rate respectively. However, under slow ramps of loading, the spectrum crosses over to a shallow-curved regime at lower strength, which is consistent with the kinetic impedance to opening an unstable hole in a fluid film. The dependence of rupture tension on rate reveals hole edge energy and frequency scale for thermal fluctuations in size. To cite this article: E. Evans, V. Heinrich, C. R. Physique 4 (2003).

  13. Collaborateurs aux lignes directrices en soins primaires

    PubMed Central

    Allan, G. Michael; Kraut, Roni; Crawshay, Aven; Korownyk, Christina; Vandermeer, Ben; Kolber, Michael R.

    2015-01-01

    Résumé Objectif Déterminer la profession des collaborateurs scientifiques aux lignes directrices, les variables associées aux différences de participation des collaborateurs et si oui ou non les lignes directrices en soins primaires fournissent un énoncé sur les conflits d’intérêts. Type d’étude Analyse rétrospective des lignes directrices en soins primaires affichées sur le site web de l’Association médicale canadienne. Deux extracteurs de données indépendants ont examiné les lignes directrices et ont extrait les données pertinentes. Contexte Canada Principaux paramètres à l’étude Commanditaires des lignes directrices, territoire (national ou provincial) visé par les lignes directrices, profession des collaborateurs scientifiques aux lignes directrices et énoncés de conflits d’intérêts rapportés dans les lignes directrices. Résultats Sur les 296 lignes directrices de pratique clinique trouvées dans la section de la médecine familiale de l’Infobanque AMC, 65 apparaissaient en double et 35 se rapportaient de façon limitée à la médecine familiale. Vingt ne fournissaient aucune information sur les collaborateurs scientifiques, ce qui laissait 176 lignes directrices propices à l’analyse. Au total, il y avait 2495 collaborateurs (auteurs et membres de comité) : 1343 (53,8 %) spécialistes autres que des médecins de famille, 423 (17,0 %) médecins de famille, 141 (5,7 %) infirmières, 75 (3,0 %) pharmaciens, 269 (10,8 %) autres cliniciens, 203 (8,1 %) scientifiques non cliniciens et 41 (1,6 %) collaborateurs de profession inconnue. La proportion des collaborateurs de ces professions différait significativement entre les lignes directrices nationales et provinciales, de même qu’entre les lignes directrices financées par l’industrie et celles qui ne l’étaient pas (p < 0,001 dans les 2 cas). Dans le cas des lignes directrices de pratique clinique provinciales, 30,8 % des collaborateurs étaient des médecins de

  14. Blast pulmonaire primaire chez le brûlé. a propos d’un cas et revue de la littérature

    PubMed Central

    Siah, S.; Emane, A.; Bertin-Maghit, M.

    2016-01-01

    Summary Le blast est à l’origine de lésions spécifiques pour lesquelles une prise en charge spécialisée est nécessaire. Après une explosion on peut observer des lésions de blast primaire, liées à l’onde de choc, secondaire par polycriblage et tertiaire par projection du patient. Les blasts secondaire et tertiaire sont plus fréquents que le blast primaire et peuvent entraîner un polytraumatisme. Dans 5% des cas, on retrouve des brûlures pouvant faire partie du blast quaternaire, qui regroupe toutes les lésions d’autres mécanismes que ceux précités. La prise en charge des lésions secondaires et tertiaires de blast est comparable à celle des traumatisés graves. Le blast pulmonaire primaire aggrave le pronostic des blessés les plus graves mais impose rarement une prise en charge spécifique. La connaissance des particularités physiopathologiques et lésionnelles permet de mieux traiter les blastés et brûlés graves survivants. Nous rapportons une observation de blast pulmonaire primaire chez un brûlé. PMID:28149247

  15. Soins primaires aux adultes ayant une déficience développementale

    PubMed Central

    Sullivan, William F.; Berg, Joseph M.; Bradley, Elspeth; Cheetham, Tom; Denton, Richard; Heng, John; Hennen, Brian; Joyce, David; Kelly, Maureen; Korossy, Marika; Lunsky, Yona; McMillan, Shirley

    2011-01-01

    Résumé Objectif Mettre à jour les lignes directrices canadiennes de 2006 sur les soins primaires aux adultes ayant une déficience développementale (DD) et présenter des recommandations pratiques fondées sur les connaissances actuelles pour traiter des problèmes de santé particuliers chez des adultes ayant une DD. Qualité des preuves Des professionnels de la santé expérimentés participant à un colloque et un groupe de travail subséquent ont discuté et convenu des révisions aux lignes directrices de 2006 en se fondant sur une recherche documentaire exhaustive, la rétroaction obtenue des utilisateurs du guide de pratique et les expériences cliniques personnelles. La plupart des preuves disponibles dans ce domaine viennent de l’opinion d’experts ou de déclarations consensuelles publiées (niveau III). Message principal Les adultes ayant une DD ont des problèmes de santé complexes, dont plusieurs diffèrent de ceux de la population en général. De bons soins primaires permettent d’identifier les problèmes de santé particuliers dont souffrent les adultes ayant une DD pour améliorer leur qualité de vie et leur accès aux soins de santé et prévenir la morbidité et le décès prématuré. Ces lignes directrices résument les problèmes de santé générale, physique, comportementale et mentale des adultes ayant une DD que devraient connaître les professionnels des soins primaires et présentent des recommandations pour le dépistage et la prise en charge en se basant sur les connaissances actuelles que les cliniciens peuvent mettre en pratique. En raison de l’interaction des facteurs biologiques, psychoaffectifs et sociaux qui contribuent à la santé et au bien-être des adultes ayant une DD, ces lignes directrices insistent sur la participation des aidants, l’adaptation des interventions, au besoin, et la consultation auprès de divers professionnels de la santé quand ils sont accessibles. Elles mettent aussi en évidence la

  16. LeČOns Sur Les Ondes De Gravité Des Fluides Incompressibles

    NASA Astrophysics Data System (ADS)

    van den Dungen, F. H.

    Le 3 Janvier 1814 au moment où les Alliés franchissant le Rhin allaient entamer la campagne de France, la classe des Sciences de l'Institut de France proposait comme sujet du grand prix de mathématique à décerner en Janvier 1816 la question suivante: "La théorie de la propagation des ondes à la surface d'un fluide pesant d'une profondeur infinie".

  17. Un mode de découverte inhabituel d'hyperparathyroïdie primaire: fractures multiples sur tumeurs brunes secondaires à un adénome parathyroïdien ectopique médiastinal

    PubMed Central

    Yassine, Asmaa; Guerboub, Ahmed Anas; Arsalane, Adil; Biyi, Abdelhamid; Moussaoui, Souad El; Belmejdoub, Ghizlaine

    2015-01-01

    La tumeur brune est une entité clinique bénigne apparaissant comme une manifestation squelettique rare de l'hyperparathyroïdie primaire. Il s'agit d'une cause inhabituelle de fractures pathologiques. Nous rapportons ici le cas clinique d'un patient âgé de 20 ans chez qui l'hyperparathyroïdie primitive a été découverte devant des tumeurs brunes multiples. PMID:26966486

  18. Tumeur brune du maxillaire révélatrice d'hyperparathyroidie primaire: à propos d'un cas et revue de la littérature

    PubMed Central

    Malika, Fassih; Taali, Loubna; Akssim, Mohamed; Reda, Abada; Rouadi, Sami; Mahtar, Mohamed; Roubal, Mohamed; Essaadi, Mustapha; Kadiri, Mohamed Fatmi El

    2013-01-01

    Les tumeurs brunes sont des lésions ostéolytiques rarement révélatrices des hyperparathyroïdies. Elles surviennent habituellement au stade terminal de l'hyperparathyroïdie primaire ou secondaire. Durant les 3 dernières décennies, le diagnostic des hyperparathyroïdies est le plus souvent fait à la phase asymptomatique grâce aux dosages systématiques du calcium et l'avènement des nouvelles techniques, de dosage de la parathormone. Nous rapportons l'observation d'une patiente avec hyperparathyroïdie primaire révélée par une tumeur du maxillaire, dont la TDM avait mis en évidence un processus ostéolytique agressif. L'intervention chirurgicale a consisté en une maxillectomie droite avec reconstruction. Le résultat anatomo-pathologique a conclu en une tumeur à cellule géantes bénigne du maxillaire. Le diagnostic de tumeur brune a été évoqué et confirmé après la réalisation d'un bilan phosphocalcique qui a mis en évidence une hypercalcémie, avec une hypophosphorémie. La recherche étiologique a objectivé à la TDM cervicale un processus en situation rétro et infra thyroïdienne droite en faveur d'un adénome parathyroïdien. Le dosage de la parathormone: 322 pmol/L a confirmé le diagnostic. Nous rappelons à travers cette observation la difficulté d’établir un diagnostic correct chez les patients avec un processus ostéolytique du maxillaire et la nécessité de rechercher une hyperparathyroïdie devant une lésion à cellules géantes vue le caractère insidieux de cette endocrinopathie. PMID:23503933

  19. Fluid Dynamics Problems of Vehicles Operating Near or in the Air-Sea Interface (Problemes de Dynamique des Fluides des Vehicules Evoluant dans ou pres de L’interface Air-Mer).

    DTIC Science & Technology

    1999-02-01

    ecoulement ä surface libre, instationnaire, couple avec des effets thermodynamiques lies aux gaz de chasse chauds et condensables. Dans une premiere...fermeture de la bulle. Dans une seconde partie une decomposition des phenomenes thermodynamiques basee sur une modelisation et des calculs numeriques [4... thermodynamiques interviennent si les gaz de chasse sont condensables. C’est ce qui arrive lorsque ces gaz resultent d’une combustion et qu’ils sont

  20. Chorologie des Tabanidae (Diptera) dans la réserve de biosphère Ipassa-Makokou (Gabon) en saison des pluies

    PubMed Central

    Mavoungou, J.F.; Makanga, B.K.; Acapovi-Yao, G.; Desquesnes, M.; M’batchi, B.

    2012-01-01

    L’abondance et la diversité spécifique des tabanidés ont été évaluées par des captures d’insectes à l’aide de pièges Vavoua durant la saison des pluies, du 4 octobre au 30 novembre 2009, dans trois types de biotope : forêt primaire, forêt secondaire et villages, dans la réserve de biosphère Ipassa-IRET Makokou au Gabon. Huit espèces de tabanidés appartenant à trois genres ont été identifiées sur un total de 402 spécimens capturés. Les espèces de tabanidés numériquement les plus abondantes ont été : Tabanus secedens Walker, 1854 (55,2 %), Tabanus obscurehirtus Ricardo, 1908 (13,9 %), Chrysops dimidiatus Wulp, 1885 (11,2 %) et Chrysops silaceus Austen, 1907 (10,7 %). Les espèces les moins abondantes ont été Tabanus par Walker, 1854 (3,2 %), Tabanus besti arbucklei Austen, 1912 (3 %), Tabanus marmorosus congoicola Bequaert, 1930 (1 %) et Ancala fasciata fasciata (Fabricius, 1775) (0,5 %). Des spécimens des genres Tabanus et Chrysops n’ont pu être déterminés, représentant respectivement des taux de 0,7 % et 0,5 % des insectes capturés. La plus forte proportion de tabanidés a été capturée en forêt secondaire (75,1 %) et la plus faible en forêt primaire (4,5 %). PMID:22550628

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

    NASA Astrophysics Data System (ADS)

    Amrani, Salah

    classifier les differentes fissurations en plusieurs categories en se basant sur certains criteres tels que le type de fissures (horizontale, verticale et inclinee), leurs localisations longitudinales (bas, milieu et haut de l'anode) et transversales (gauche, centrale et droite). Les effets de la matiere premiere, les parametres de fabrication des anodes crues ainsi que les conditions de cuisson sur la fissuration ont ete etudies. La fissuration des anodes denses en carbones cause un serieux probleme pour l'industrie d'aluminium primaire. La realisation de ce projet a permis la revelation de differents mecanismes de fissuration, la classification de fissuration par plusieurs criteres (position, types localisation) et l'evaluation de l'impact de differents parametres sur la fissuration. Les etudes effectuees dans le domaine de cuisson ont donne la possibilite d'ameliorer l'operation et reduire la fissuration des anodes. Le travail consiste aussi a identifier des techniques capables d'evaluer la qualite d'anodes (l'ultrason, la tomographie et la distribution de la resistivite electrique). La fissuration des anodes en carbone est consideree comme un probleme complexe, car son apparition depend de plusieurs parametres repartis sur toute la chaine de production. Dans ce projet, plusieurs nouvelles etudes ont ete realisees, et elles permettent de donner de l'originalite aux travaux de recherches faits dans le domaine de la fissuration des anodes de carbone pour l'industrie de l'aluminium primaire. Les etudes realisees dans ce projet permettent d'ajouter d'un cote, une valeur scientifique pour mieux comprendre le probleme de fissuration des anodes et d'un autre cote, d'essayer de proposer des methodes qui peuvent reduire ce probleme a l'echelle industrielle.

  2. Structure des fluides de bâtonnets polaires et polarisables dans l'approximation des chaînes hypertressées avec amplification du potentiel répulsif. Un modèle simple d'acétonitrile liquide.

    NASA Astrophysics Data System (ADS)

    Salamito, B.; Fries, P. H.

    1991-07-01

    We study fluids of rigid rods which are generated by a distribution of line sites and which carry a polarizable electric point dipole at their centre. We examine the difficulties for solving the integral equations, which result from truncating the rotational invariant expansion of the usual intermolecular rapidly varying shape potentials. In order to overcome these convergence problems, soft shape potentials are used in addition to an approximation HNCAR, of the hypernetted chain (HNC) type, which Amplifies these soft Repulsive effects. The polarization due to all the molecules is treated at a self-consistent mean field level. This formalism is applied to a model of liquid acetonitrile at 291K. The Kirkwood factors, the dielectric constant, and the cross sections of neutron or X-rays diffraction studies are in good agreement with experiment. This justifies the theoretical molecular pair distribution, from which the local molecular order is carefully analyzed. On étudie des fluides de bâtonnets rigides engendrés par une distribution de sites alignés et portant en leur centre un dipôle électrique ponctuel polarisable. On examine les difficultés de résolution des équations intégrales liées à la troncature du développement en invariants rotationnels des potentiels de forme intermoléculaires usuels à variation rapide. Pour contourner ces problèmes de convergence on utilise des potentiels de forme molle combinés à une approximation HNCAR, du type des chaînes hypertressées (HNC), qui Amplifie ces effets Répulsifs mous. On traite la polarisation due à l'ensemble des molécules par une approximation auto-cohérente de champ moyen. On applique ce formalisme à un modèle d'acétonitrile liquide à 291K. Les facteurs de Kirkwood, la constante diélectrique et les sections efficaces de diffusion des neutrons ou des rayons X calculés sont en bon accord avec l'expérience. Ceci justifie la distribution théorique de paires de molécules à partir de

  3. Regles de fusion en theorie des champs conformes

    NASA Astrophysics Data System (ADS)

    Begin, Luc

    1999-10-01

    Les théories de champs conformes constituent un domaine de recherche très actif avec de nombreuses applications en physique statistique, en matière condensée, en théorie des cordes, en mathématiques, etc. Nous analysons ici le calcul des règles de fusion dans les modèles Wess- Zumino-Witten par des méthodes positives. Les règles de fusion sont des quantités importantes puisqu'elles indiquent comment se combinent les champs primaires de la théorie. L'approche présentée est basée sur l'hypothèse que les règles de fusion sont décrites par un système d'inéquations linéaire et homogène et mène au concept original de «base de fusion». Cette approche simple et générale permet d'utiliser les méthodes combinatoires et de programmation linéaire pour construire les fonctions génératrices et les bases de fusion. Cette méthode permet d'obtenir des résultats originaux et explicites pour les algèbres su (3), su (4) et sp (4).

  4. Approche en soins primaires pour les problèmes de consommation de cannabis

    PubMed Central

    Turner, Suzanne D.; Spithoff, Sheryl; Kahan, Meldon

    2014-01-01

    Résumé Objectif Étudier les caractéristiques et complications cliniques de la consommation à risque de cannabis et du trouble de consommation de cannabis, et présenter un protocole en cabinet pour le dépistage, l’identification et la prise en charge de ces problèmes. Sources des données Une recherche des essais contrôlés, des études d’observation et des révisions sur l’usage de cannabis par les adolescents et les jeunes adultes; les méfaits psychiatriques et médicaux liés au cannabis; le trouble de consommation de cannabis et son traitement; et les lignes directrices sur la consommation à faible risque de cannabis a été effectuée dans PubMed. Message principal Les médecins doivent questionner tous leurs patients quant à leur usage de cannabis. Ils doivent questionner plus souvent les adolescents et jeunes adultes de même que les personnes qui présentent un risque élevé de problèmes liés au cannabis (qui ont un trouble psychiatrique ou de consommation de drogue concomitant). Les problèmes pouvant être causés par le cannabis, comme les troubles de l’humeur, la psychose et les symptômes respiratoires, devraient susciter des questions sur la consommation de cannabis. Aux patients qui rapportent un usage de cannabis, les médecins devraient poser des questions sur la fréquence et la quantité consommée, la présence de symptômes de tolérance ou de sevrage, les tentatives de réduire leur consommation et la présence de problèmes liés au cannabis. Les usagers à faible risque fument, inhalent ou ingèrent le cannabis occasionnellement sans aucun signe de dysfonctionnement scolaire, professionnel ou social; les personnes dont l’usage est problématique consomment tous les jours ou presque tous les jours, ont de la difficulté à réduire leur consommation et leur fonctionnement scolaire, professionnel et social est perturbé. Les médecins devraient offrir à tous les patients dont l’usage est problématique des conseils

  5. Agénésie bilatérale des vésicules séminales et des canaux déférents

    PubMed Central

    Kassogué, Amadou; El Ammari, J. Eddine; Diarra, Alkadri; Amiroune, Driss; Ahsaini, Mustapha; Ouldim, Karim; Traoré, Zacharia; Sqalli, H. Nadia; Tizniti, Siham; Mellas, Soufiane; Tazi, M. Fadl; Khallouk, Abdelhak; El Fassi, M. Jamal; Farih, My Hassan

    2014-01-01

    Résumé L’absence de canaux déférents et de vésicules séminales est une cause très rare d’infertilité masculine qui pose des difficultés d’ordre diagnostique. De plus, son traitement est complexe. Dans le présent article, nous rapportons le cas d’un patient âgé de 43 ans qui a consulté pour infertilité primaire évoluant depuis 5 ans (un conseil génétique a été réalisé) et nous examinons les difficultés diagnostiques et thérapeutiques liées à cette forme particulière d’infertilité. PMID:25132895

  6. Des Moines.

    ERIC Educational Resources Information Center

    Gore, Deborah, Ed.

    1988-01-01

    This document, intended for elementary students, contains articles and activities designed to acquaint young people with the history of Des Moines, Iowa. The articles are short, and new or difficult words are highlighted and defined for young readers. "The Raccoon River Indian Agency" discusses the archeological exploration of the indian…

  7. Fluid imbalance

    MedlinePlus

    ... up in the body. This is called fluid overload (volume overload). This can lead to edema (excess fluid in ... Water imbalance; Fluid imbalance - dehydration; Fluid buildup; Fluid overload; Volume overload; Loss of fluids; Edema - fluid imbalance; ...

  8. Approche aux soins en milieu communautaire à des adultes ayant une déficience développementale

    PubMed Central

    Osmun, W.E.; Chan, Nelson; Solomon, Robert

    2015-01-01

    Résumé Objectif Passer en revue les obligations d’ordre médical, éthique et juridique dans les soins aux adultes ayant une déficience développementale (DD) qui vivent dans la communauté. Sources des données Des recherches ont été faites dans Google et MEDLINE à l’aide des mots disabled, disability, vulnerable et community. Les lois pertinentes ont fait l’objet d’un examen. Message principal Le traitement d’un patient ayant une DD varie en fonction de facteurs comme la pathogenèse du problème actuel du patient, ses affections concomitantes, la gravité de ses déficiences et ses soutiens sociaux habituels. Bien que l’on s’entende sur les bienfaits du transfert des soins institutionnels vers des soins communautaires pour les patients ayant une DD, il s’est révélé difficile de leur dispenser des soins de grande qualité en milieu communautaire. Par ailleurs, il existe peu de travaux de recherche sur les façons d’offrir efficacement des soins aux adultes ayant une DD. En tant que professionnels des soins primaires, les médecins de famille sont souvent le premier point de contact pour les patients et sont à la fois responsables de la coordination et de la continuité des soins. Compte tenu de l’importance accrue accordée aux soins préventifs et à la détection précoce des maladies, la participation active du patient revêt aussi une grande importance. Les valeurs et les objectifs du patient sont des éléments essentiels à prendre en compte, même s’ils vont à l’encontre de la bonne santé du patient ou des propres valeurs du clinicien. Les lois s’appliquant aux personnes vulnérables varient d’une province à l’autre. Par conséquent, l’obligation de signaler des mauvais traitements suspectés pourrait différer selon que la personne vulnérable habite dans un centre de soins ou la communauté, que la personne qui soupçonne le comportement abusif est un fournisseur de services ou un professionnel de la santé ou

  9. La prise en charge des troubles de santé mentale par les omnipraticiens du Québec

    PubMed Central

    Fleury, Marie-Josée; Farand, Lambert; Aubé, Denise; Imboua, Armelle

    2012-01-01

    services (ressources; coordination formalisée) et l’environnement (politiques). Conclusion Le rôle clé des omnipraticiens et leur soutien à la prise en charge des TM ont été démontrés, spécifiquement pour les TMC. Pour une prise en charge optimale des soins primaires de santé mentale, des stratégies à composantes multiples, dont les soins partagés, devraient être davantage déployées.

  10. Caracterisation des proprietes acoustiques des materiaux poreux a cellules ouvertes et a matrice rigide ou souple

    NASA Astrophysics Data System (ADS)

    Salissou, Yacoubou

    L'objectif global vise par les travaux de cette these est d'ameliorer la caracterisation des proprietes macroscopiques des materiaux poreux a structure rigide ou souple par des approches inverses et indirectes basees sur des mesures acoustiques faites en tube d'impedance. La precision des approches inverses et indirectes utilisees aujourd'hui est principalement limitee par la qualite des mesures acoustiques obtenues en tube d'impedance. En consequence, cette these se penche sur quatre problemes qui aideront a l'atteinte de l'objectif global precite. Le premier probleme porte sur une caracterisation precise de la porosite ouverte des materiaux poreux. Cette propriete en est une de passage permettant de lier la mesure des proprietes dynamiques acoustiques d'un materiau poreux aux proprietes effectives de sa phase fluide decrite par les modeles semi-phenomenologiques. Le deuxieme probleme traite de l'hypothese de symetrie des materiaux poreux selon leur epaisseur ou un index et un critere sont proposes pour quantifier l'asymetrie d'un materiau. Cette hypothese est souvent source d'imprecision des methodes de caracterisation inverses et indirectes en tube d'impedance. Le critere d'asymetrie propose permet ainsi de s'assurer de l'applicabilite et de la precision de ces methodes pour un materiau donne. Le troisieme probleme vise a mieux comprendre le probleme de transmission sonore en tube d'impedance en presentant pour la premiere fois un developpement exact du probleme par decomposition d'ondes. Ce developpement permet d'etablir clairement les limites des nombreuses methodes existantes basees sur des tubes de transmission a 2, 3 ou 4 microphones. La meilleure comprehension de ce probleme de transmission est importante puisque c'est par ce type de mesures que des methodes permettent d'extraire successivement la matrice de transfert d'un materiau poreux et ses proprietes dynamiques intrinseques comme son impedance caracteristique et son nombre d'onde complexe. Enfin, le

  11. Tumeur brune de la mandibule révélatrice d'une hyperparathyroïdie primaire: à propos d'un cas

    PubMed Central

    Aljalil, Abdelfattah; Bouaity, Brahim

    2014-01-01

    Les tumeurs brunes sont des manifestations osseuses classiques des hyperparathyroïdies (HPT). Elles surviennent habituellement lors des formes sévères accompagnées de signes de résorption osseuse périostée. La mandibule en constitue une localisation habituelle mais rarement révélatrice. Leur traitement repose essentiellement sur la paratharoïdectomie. Nous décrivons un cas de tumeur brune de la mandibule chez un patient de 46 ans; ainsi que son évolution favorable après para thyroïdectomie. PMID:25419327

  12. Amniotic fluid

    MedlinePlus

    ... carefully. Removing a sample of the fluid through amniocentesis can provide information about the sex, health, and development of the fetus. Images Amniocentesis Amniotic fluid Polyhydramnios Amniotic fluid References Cunningham FG, ...

  13. Note des Éditeurs scientifiques

    NASA Astrophysics Data System (ADS)

    Averbuch, P.

    Cette série d'articles est une revue de résultats expérimentaux sur différents "fluides" moléculaires, dans lesquels la cohésion est due à des forces de Van der Waals et à des liaisons hydrogène, l'eau étant un de ces fluides. Ces résultats sont présentés de façon à justifier expérimentalement un modèle original, non extensif, des propriétés de ces fluides, et l'ensemble se présente sous la forme de trois articles décrivant le modèle, suivis chacun par un article le comparant aux résultats expérimentaux publiés par de nombreux auteurs. Le caractère non extensif des propriétés physiques des fluides est choquant, contraire à beaucoup d'idées établies, il semble n'avoir en sa faveur qu'un argument, la comparaison avec un nombre de résultats expérimentaux assez grand pour que l'effet du hasard soit difficilement soupçonnable. En particulier, les écarts entre des résultats de mesures faits par des auteurs différents dans des conditions différentes sont expliqués, le sérieux et la compétence des différents expérimentateurs ne sont plus mis en doute : mais l'interprétation de ces résultats avec un modèle extensif non adapté est seule mise en cause. Les modèles extensifs étant utilisés systématiquement, au delà des expériences de physiciens, dans les calculs d'ingénieurs, et dans la modélisation d'appareils qui fonctionnent et de phénomènes naturels observés par tout le monde, il fallait expliquer pourquoi on pouvait renoncer à l'extensivité. Les raisons du succès pratique des modèles extensifs sont données, d'abord dans le cas des nématiques, puis dans celui des liquides ordinaires, et c'est ce qui rend l'ensemble cohérent, tant avec les mesures physiques fines qu'avec les observations quotidiennes. Il n'en reste pas moins que si l'interprétation donnée dans cette série d'articles est généralisable, une justification théorique du modèle utilisé devient nécessaire. Pour ce qui est des propriétés d

  14. État de santé des nouveaux réfugiés à Toronto, en Ontario

    PubMed Central

    Redditt, Vanessa J.; Janakiram, Praseedha; Graziano, Daniela; Rashid, Meb

    2015-01-01

    Résumé Objectif Déterminer la prévalence de certaines maladies infectieuses parmi les patients nouvellement réfugiés et la présence ou non d’une variation en fonction de facteurs démographiques clés. Conception Revue rétrospective de dossiers. Contexte Clinique de soins primaires pour patients réfugiés à Toronto, en Ontario. Participants Au total, 1063 patients réfugiés inscrits à la clinique entre décembre 2011 à juin 2014. Principaux paramètres à l’étude Données démographiques (âge, sexe et pays de naissance); prévalence de VIH, d’hépatite B, d’hépatite C, d’infections à strongyloïdes, à schistosomes, à parasite intestinal, de gonorrhée, de chlamydia et de syphilis; et immunité contre la varicelle. Résultats L’âge médian des patients était de 29 ans et 56 % étaient de sexe féminin. Les réfugiés étaient nés dans 87 pays différents. Environ 33 % des patients étaient originaires d’Afrique, 28 % d’Europe, 14 % de la région de la Méditerranée orientale, 14 % d’Asie et 8 % des Amériques (à l’exception de 4 % nés au Canada ou aux États-Unis). Le taux global de VIH était de 2 %. La prévalence d’hépatite B était de 4 %, ce taux étant supérieur parmi les réfugiés originaires d’Asie (12 %, p < 0,001). L’immunité contre l’hépatite B était de 39 %, ce taux étant supérieur parmi les réfugiés originaires d’Asie (64 %, p < 0,001) et les enfants de moins de 5 ans (68 %, p < 0,001). Le taux d’hépatite C se situait à moins de 1 %. Une infection à strongyloïdes a été dépistée chez 3 % des patients testés, ce taux étant supérieur parmi les réfugiés originaires d’Afrique (6 %, p = 0,003). Une infection à schistosomes a été dépistée chez 15 % des patients africains. Des parasites intestinaux ont été observés chez 16 % des patients ayant soumis un échantillon de selles. Environ 8 % des patients n’étaient pas immunisés contre la varicelle, ce taux étant sup

  15. Des ballons pour demain

    NASA Astrophysics Data System (ADS)

    Régipa, R.

    A partir d'une théorie sur la détermination des formes et des contraintes globales d'un ballon de révolution, ou s'en rapprochant, une nouvelle famille de ballons a été définie. Les ballons actuels, dits de ``forme naturelle'', sont calculés en général pour une tension circonférencielle nulle. Ainsi, pour une mission donnée, la tension longitudinale et la forme de l'enveloppe sont strictement imposées. Les ballons de la nouvelle génération sont globalement cylindriques et leurs pôles sont réunis par un câble axial, chargé de transmettre une partie des efforts depuis le crochet (pôle inférieur), directement au pôle supérieur. De plus, la zone latérale cylindrique est soumise à un faible champ de tensions circonférencielles. Ainsi, deux paramètres permettent de faire évoluer la distribution des tensions et la forme de l'enveloppe: - la tension du câble de liaison entre pôles (ou la longueur de ce câble) - la tension circonférencielle moyenne désirée (ou le rayon du ballon). On peut donc calculer et réaliser: - soit des ballons de forme adaptée, comme les ballons à fond plat pour le bon fonctionnement des montgolfières infrarouge (projet MIR); - soit des ballons optimisés pour une bonne répartition des contraintes et une meilleure utilisation des matériaux d'enveloppe, pour l'ensemble des programmes stratosphériques. Il s'ensuit une économie sensible des coûts de fabrication, une fiabilité accrue du fonctionnement de ces ballons et une rendement opérationnel bien supérieur, permettant entre autres, d'envisager des vols à très haute altitude en matériaux très légers.

  16. La dermoscopie pour la détection des mélanomes en pratique familiale

    PubMed Central

    Herschorn, Andrea

    2012-01-01

    Résumé Objectif Évaluer l’exactitude diagnostique et l’utilité clinique de la dermoscopie pour la détection de mélanomes en pratique familiale. Sources des données Nous avons fait une recension dans les bases de données Ovid MEDLINE (de 1946 à juin 2011), EMBASE, PubMed et Cochrane à l’aide des expressions suivantes en anglais: dermoscopy, dermatoscopy, epiluminescence microscopy, family practice, general practice, primary health care, melanoma, skin neoplasms et pigmented nevus. Pour être prises en considération, les études devaient être des articles de recherche primaire ayant pour sujets des médecins de famille, ainsi que la formation en dermoscopie et son utilisation en tant qu’intervention. La recherche a produit 4 articles qui répondaient aux critères d’inclusion et présentaient des données probantes de niveau I selon la définition du Groupe d’étude canadien sur les soins de santé préventifs. Message principal Dans le milieu de la pratique familiale, la dermoscopie a une sensibilité plus élevée que l’examen à l’œil nu pour la détection des mélanomes sans avoir, généralement, une spécificité moins grande. La dermoscopie aide aussi à accroître le degré de confiance des médecins de famille dans leur diagnostic préliminaire des lésions. L’utilisation de la dermoscopie plutôt que l’examen à l’œil nu augmente la probabilité qu’une lésion jugée cancéreuse le soit de fait et qu’une lésion jugée bénigne le soit en réalité. Conclusion Il est démontré que la dermoscopie est un outil utile et relativement peu coûteux pour la détection des mélanomes en pratique familiale. Cette technique rend les médecins de famille plus confiants dans l’exactitude de leurs demandes de consultations auprès de dermatologues et contribue à diminuer les biopsies inutiles. La dermoscopie peut se révéler plus particulièrement utile dans l’examen des patients à risque élevé de mélanomes, étant donn

  17. Maladie des vibrations

    PubMed Central

    Shen, Shixin (Cindy); House, Ronald A.

    2017-01-01

    Résumé Objectif Permettre aux médecins de famille de comprendre l’épidémiologie, la pathogenèse, les symptômes, le diagnostic et la prise en charge de la maladie des vibrations, une maladie professionnelle importante et courante au Canada. Sources d’information Une recherche a été effectuée sur MEDLINE afin de relever les recherches et comptes rendus portant sur la maladie des vibrations. Une recherche a été effectuée sur Google dans le but d’obtenir la littérature grise qui convient au contexte canadien. D’autres références ont été tirées des articles relevés. Message principal La maladie des vibrations est une maladie professionnelle répandue touchant les travailleurs de diverses industries qui utilisent des outils vibrants. La maladie est cependant sous-diagnostiquée au Canada. Elle compte 3 éléments : vasculaire, sous la forme d’un phénomène de Raynaud secondaire; neurosensoriel; et musculosquelettique. Aux stades les plus avancés, la maladie des vibrations entraîne une invalidité importante et une piètre qualité de vie. Son diagnostic exige une anamnèse minutieuse, en particulier des antécédents professionnels, un examen physique, des analyses de laboratoire afin d’éliminer les autres diagnostics, et la recommandation en médecine du travail aux fins d’investigations plus poussées. La prise en charge consiste à réduire l’exposition aux vibrations, éviter les températures froides, abandonner le tabac et administrer des médicaments. Conclusion Pour assurer un diagnostic rapide de la maladie des vibrations et améliorer le pronostic et la qualité de vie, les médecins de famille devraient connaître cette maladie professionnelle courante, et pouvoir obtenir les détails pertinents durant l’anamnèse, recommander les patients aux cliniques de médecine du travail et débuter les demandes d’indemnisation de manière appropriée. PMID:28292812

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

    NASA Astrophysics Data System (ADS)

    Bendaoud, Adlane Larbi

    . Dans la partie theorique, un modele traitant les aspects thermique, hydrodynamique et massique a ete elabore. Sur la base de ce modele a ete ecrit un programme informatique en langage FORTRAN 6.6. Il est base sur la discretisation du serpentin en volumes de controle, est entierement automatise et peut traiter des echangeurs de chaleur avec des circuits de refrigerant complexes pouvant avoir des entrees et sorties multiples ainsi que des bifurcations. La presence simultanee des trois phases thermodynamiques du refrigerant (liquide sous refroidi, fluide sature, vapeur surchauffee) dans le serpentin est aussi prise en charge. Le modele a ete valide pour un fonctionnement avec et sans formation de givre en utilisant des donnees experimentales disponibles dans la litterature et celles obtenues sur le banc d'essai de CanmetENERGIE. Celui-ci a ete mis a jour pour les besoins de la presente recherche et pour cela, un systeme de surchauffe et d'injection de la vapeur d'eau dans une enceinte a tres basse temperature a ete dimensionne, fabrique et installe. Un dispositif de visualisation de la formation de givre, ainsi qu'un equipement de mesure de la temperature, de la pression et de l'humidite relative de l'air ont aussi ete ajoutes. Une fois le modele valide, des simulations numeriques sur le serpentin avec et sans formation de givre ont ete effectuees. Un premier cas de base a servi comme reference pour d'autres cas pour lesquels une etude parametrique sur la geometrie et le fonctionnement a ete menee. Il a ete montre par rapport au cas de base que : 1. la diminution de la densite des ailettes sur des rangees specifiques du serpentin donne une surface minimale (Amin) plus grande, retardant ainsi l'obstruction totale du serpentin par le givre et permet donc un temps de fonctionnement plus grand et une frequence de degivrage plus faible. 2. une bonne configuration de circuit de refrigerant augmente le temps de fonctionnement du serpentin de 200 % et delivre une puissance

  19. Des Vents et des Jets Astrophysiques

    NASA Astrophysics Data System (ADS)

    Sauty, C.

    well expected result from the theory. Although, collimation may be conical, paraboloidal or cylindrical (Part 4), cylindrical collimation is the more likely to occur. The shape of outflows may then be used as a tool to predict physical conditions on the flows or on their source. L'éjection continue de plasma autour d'objets massifs est un phénomène largement répandu en astrophysique, que ce soit sous la forme du vent solaire, de vents stellaires, de jets d'étoiles en formation, de jets stellaires autour d'objets compacts ou de jets extra-galactiques. Cette zoologie diversifiée fait pourtant l'objet d'un commun effort de modélisation. Le but de cette revue est d'abord de présenter qualitativement le développement, depuis leur origine, des diverses théories de vents (Partie 1) et l'inter disciplinarité dans ce domaine. Il s'agit d'une énumération, plus ou moins exhaustive, des idées proposées pour expliquer l'accélération et la morphologie des vents et des jets, accompagnée d'une présentation sommaire des aspects observationnels. Cette partie s'abstient de tout aspect faisant appel au formalisme mathématique. Ces écoulements peuvent être décrits, au moins partiellement, en résolvant les équations magnétohydrodynamiques, axisymétriques et stationnaires. Ce formalisme, à la base de la plupart des théories, est exposé dans la Partie 2. Il permet d'introduire quantitativement les intégrales premières qu'un tel système possède. Ces dernières sont amenées à jouer un rôle important dans la compréhension des phénomènes d'accélération ou de collimation, en particulier le taux de perte de masse, le taux de perte de moment angulaire ou l'énergie du rotateur magnétique. La difficulté de modélisation réside dans l'existence de points critiques, propres aux équations non linéaires, qu'il faut franchir. La nature physique et la localisation de ces points critiques fait l'objet d'un débat important car ils sont la clef de voute de la r

  20. Fluid Mechanics.

    ERIC Educational Resources Information Center

    Drazin, Philip

    1987-01-01

    Outlines the contents of Volume II of "Principia" by Sir Isaac Newton. Reviews the contributions of subsequent scientists to the physics of fluid dynamics. Discusses the treatment of fluid mechanics in physics curricula. Highlights a few of the problems of modern research in fluid dynamics. Shows that problems still remain. (CW)

  1. Etude de Retour/Non-Retour des Étudiants Marocains en France (le cas de Lille)

    NASA Astrophysics Data System (ADS)

    El Attafi, Douieb

    1990-12-01

    Indépendamment de l'intention de retour ou de non-retour, les étudiants marocains à Lille sont en général appelés à créer leurs conditions matérielles d'existence et par là, à conduire des stratégies professionnelles et sociales d'intégration à la société française bien au delà de ce qu'exigerait un simple séjour d'étude. Ces mêmes étudiants pensent qu'au Maroc, la valorisation des qualifications acquises en France est incertaine. Le chômage des diplômés au Maroc devient une réalité de plus en plus tangible. Les étudiants marocains à Lille, incertains de pouvoir s'insérer professionnellement au Maroc, lorsqu'ils réussissent à obtenir un emploi relativement déclassé, mais qualifiant, décident de rester en France. Ceci est d'autant plus probable quand, chez les étudiants, la religion n'est pas fortement intégrée. Dans le cas contraire et lorsque ils décident de rester en France, la religion comme effet durable de la socialisation primaire, constitue un point d'ancrage plus ou moins spécifique, leur permettant de réinterpréter les ruptures vécues, sous le mode de la continuité. Tout ceci montre que dans leurs choix de retour/non-retour, les étudiants sont bien évidemment conditionnés de leur histoire individuelle et collective, mais ils n'en sont pas entièrement prisonniers.

  2. Gestion des déchets ménagers dans l’aire de santé Bulaska à Mbuji-Mayi en République Démocratique du Congo

    PubMed Central

    Kangoy, Kasangye; Ngoyi, John; Mudimbiyi, Olive

    2016-01-01

    Introduction La présence des déchets ménagers dans les voies publiques a une influence sur l’hygiène de l’environnement, ils entrainent l’insalubrité et peuvent être facteurs des certaines maladies dont quelques-unes peuvent être épidémiques. Au cours des deux dernières décennies, la question de la gestion des déchets est devenue de plus en plus complexe autant pour les pays développés que ceux sous-développés. L’objectif de cette étude était de déterminer les types de déchets et le mode de gestion des déchets génère par les ménages. Méthodes Cette étude est descriptive transversale, réalisée dans l’aire de sante Bulaska, Kasaï oriental, c’est une approche prospective appuyée par l’interview et l’observation active. Le questionnaire a été adressé au responsable du ménage ou au délègue, du 21 au 25 juin 2010, sur 170 ménages ce qui constituent un échantillon de convenance. Résultats Cette étude a révélé ce qui suit: 94,7% des enquêtes qui avaient répondu a notre questionnaire étaient de sexe féminin; 47% des enquêtes avaient un niveau d’étude primaire; 41,1% des enquêtes étaient des ménagères; la taille médiane de ménage était de 7 personnes par ménage; dans 83,5% des cas les déchets génères étaient solides; 50% des ménages de l’aire de sante utilisent la voie publique comme poubelle. Conclusion Eu égard au résultat de cette étude, développer plus les programmes de sensibilisation sur l’assainissement de l’environnement s’avère nécessaire. PMID:27800105

  3. Electrorheological fluids

    SciTech Connect

    Adolf, D.; Anderson, R.; Garino, T.; Halsey, T.C.; Hance, B.; Martin, J.E.; Odinek, J.

    1996-10-01

    An Electrorheological fluid is normally a low-viscosity colloidal suspension, but when an electric field is applied, the fluid undergoes a reversible transition to a solid, being able to support considerable stress without yield. Commercial possibilities for such fluids are enormous, including clutches, brakes, valves,shock absorbers, and stepper motors. However, performance of current fluids is inadequate for many proposed applications. Our goal was to engineer improved fluids by investigating the key technical issues underlying the solid-phase yield stress and the liquid to solid switching time. Our studies focused on field-induced interactions between colloidal particles that lead to solidification, the relation between fluid structure and performance (viscosity, yield stress), and the time evolution of structure in the fluid as the field is switched on or off.

  4. Utilisation des micro-ordinateurs en ecriture aux cycles primaire et moyen: methodes, roles, attitudes et produits. L'education et la technologie (Writing with Microcomputers in the Elementary Grades: Process, Roles, Attitudes, and Products. Education and Technology Series).

    ERIC Educational Resources Information Center

    Larter, Sylvia; And Others

    A study examined and compared writing with and without microcomputers in elementary schools. Specifically, the study examined (1) how the products of writing instruction with a computer differ from the products of traditionally taught writing, (2) the process of teaching writing, (3) teacher-pupil roles when pupils are writing, (4) teacher…

  5. Injectabilite des coulis de ciment dans des milieux fissures

    NASA Astrophysics Data System (ADS)

    Mnif, Thameur

    Le travail presente ici est un bilan du travaux de recherche effectues sur l'injectabilite des coulis de ciment dans lu milieux fissures. Un certain nombre de coulis a base de ciment Portland et microfin ont ete selectionnes afin de caracteriser leur capacite a penetrer des milieux fissures. Une partie des essais a ete menee en laboratoire. L'etude rheologique des differents melanges a permis de tester l'influence de l'ajout de superplastifiant et/ou de fumee de silice sur la distribution granulometrique des coulis et par consequent sur leur capacite a injecter des colonnes de sable simulant un milieu fissure donne. La classe granulometrique d'un coulis, sa stabilite et sa fluidite sont apparus comme les trois facteurs principaux pour la reussite d'une injection. Un facteur de finesse a ete defini au cours de cette etude: base sur la classe granulometrique du ciment et sa stabilite, il peut entrer dans la formulation theorique du debit d'injection avant application sur chantier. La deuxieme et derniere partie de l'etude presente les resultats de deux projets de recherche sur l'injection realises sur chantier. L'injection de dalles de beton fissurees a permis le suivi de l'evolution des pressions avec la distance au point d'injection. L'injection de murs de maconnerie a caractere historique a montre l'importance de la definition de criteres de performance des coulis a utiliser pour traiter un milieu donne et pour un objectif donne. Plusieurs melanges peuvent ainsi etre predefinis et mis a disposition sur le chantier. La complementarite des ciments traditionnels et des ciments microfins devient alors un atout important. Le choix d'utilisation de ces melanges est fonction du terrain rencontre. En conclusion, cette recherche etablit une methodologie pour la selection des coulis a base de ciment et des pressions d'injection en fonction de l'ouverture des fissures ou joints de construction.

  6. Environnement des Systèmes Binaires Jeunes

    NASA Astrophysics Data System (ADS)

    Duchene, Gaspard

    2000-07-01

    %. Dans les amas les plus denses, cette fraction peut ensuite être rapidement réduite du fait des nombreuses interactions gravitationnelles destructrices entre systèmes proches. D'autres interprétations restent toutefois envisageables. Je m'intéresse ensuite au phénomène d'accrétion dans les binaires T Tauri par la spectroscopie visible des composantes de ces systèmes. Cette approche révèle que le phénomène d'accrétion perdure aussi longtemps sur les deux composantes d'une même binaire. De plus, la comparaison des luminosités émises dans la raie H? montre que le primaire présente généralement le taux d'accrétion le plus élevé. Une interprétation possible de ces observations est que ces binaires possèdent des réservoirs circumbinaires de matière, probablement sous la forme d'une vaste enveloppe, qui alimentent simultanément les deux disques circumstellaires. Enfin, je présente des images à haute résolution angulaire des disques circumbinaires de GG Tau et UY Aur et des disques circumstellaires de HK Tau B et HV Tau C. Ces observations, obtenues dans le visible, le proche infrarouge et le domaine radio, permettent une description fine de l'environnement de ces binaires. Je détaille également l'analyse de cartes de polarisation des deux disques circumbinaires obtenues à 1 micron. Afin de déterminer les propriétés géométriques de ces disques et celles des grains de poussière qui s'y trouvent, j'ai entrepris une modélisation de la diffusion multiple de la lumière en utilisant une approche Monte-Carlo. Cette étude indique que l'anneau circumbinaire de GG Tau est géométriquement épais (avec un rapport d'aspect h/r~0.18), qu'il comporte des grains de poussière très petits (<1 micron) et que la masse totale de poussière dans l'anneau est au moins 10-3 masses solaires. L'environnement de UY Aur apparaît beaucoup plus complexe que celui de GG Tau: le disque circumbinaire, dont l'inclinaison est ré-évaluée à environ 60 degr

  7. Fluid Shifts

    NASA Technical Reports Server (NTRS)

    Stenger, M.; Hargens, A.; Dulchavsky, S.; Ebert, D.; Lee, S.; Lauriie, S.; Garcia, K.; Sargsyan, A.; Martin, D.; Ribeiro, L.; Lui, J.; Macias, B.; Arbeille, P.; Danielson, R.; Chang, D.; Johnston, S.; Ploutz-Snyder, R.; Smith, S.

    2016-01-01

    NASA is focusing on long-duration missions on the International Space Station (ISS) and future exploration-class missions beyond low-Earth orbit. Visual acuity changes observed after short-duration missions were largely transient, but more than 50% of ISS astronauts experienced more profound, chronic changes with objective structural and functional findings such as papilledema and choroidal folds. Globe flattening, optic nerve sheath dilation, and optic nerve tortuosity also are apparent. This pattern is referred to as the visual impairment and intracranial pressure (VIIP) syndrome. VIIP signs and symptoms, as well as postflight lumbar puncture data, suggest that elevated intracranial pressure (ICP) may be associated with the spaceflight-induced cephalad fluid shifts, but this hypothesis has not been tested. The purpose of this study is to characterize fluid distribution and compartmentalization associated with long-duration spaceflight, and to correlate these findings with vision changes and other elements of the VIIP syndrome. We also seek to determine whether the magnitude of fluid shifts during spaceflight, as well as the VIIP-related effects of those shifts, is predicted by the crewmember's preflight conditions and responses to acute hemodynamic manipulations (such as head-down tilt). Lastly, we will evaluate the patterns of fluid distribution in ISS astronauts during acute reversal of fluid shifts through application of lower body negative pressure (LBNP) interventions to characterize and explain general and individual responses. METHODS: We will examine a variety of physiologic variables in 10 long-duration ISS crewmembers using the test conditions and timeline presented in the Figure below. Measures include: (1) fluid compartmentalization (total body water by D2O, extracellular fluid by NaBr, intracellular fluid by calculation, plasma volume by CO rebreathe, interstitial fluid by calculation); (2) forehead/eyelids, tibia, calcaneus tissue thickness (by

  8. Wellbore fluid

    SciTech Connect

    Dorsey, D.L.; Corley, W.T.

    1983-12-27

    A clay-based or clay-free aqueous thixotropic wellbore fluid having improved fluid loss control, desirable flow characteristics and low shale sensitivity for use in drilling a well comprising water or a brine base including an effective amount of an additive comprising a crosslinked potato starch, a heteropolysaccharide derived from a carbohydrate by bacteria of the genus Xanthomonas, and hydroxyethylcellulose or carboxymethylcellulose, is disclosed. This drilling fluid has been found to be nondamaging to the formations through which the well is drilled.

  9. Grundlagen des Tissue Engineering

    NASA Astrophysics Data System (ADS)

    Mayer, Jörg; Blum, Janaki; Wintermantel, Erich

    Die Organtransplantation stellt eine verbreitete Therapie dar, um bei krankheitsoder unfallbedingter Schädigung eines Organs die Gesamtheit seiner Funktionen wieder herzustellen, indem es durch ein Spenderorgan ersetzt wird. Organtransplantationen werden für die Leber, die Niere, die Lunge, das Herz oder bei schweren grossflächigen Verbrennungen der Haut vorgenommen. Der grosse apparative, personelle und logistische Aufwand und die Risiken der Transplantationschirurgie (Abstossungsreaktionen) sowie die mangelnde Verfügbarkeit von immunologisch kompatiblen Spenderorganen führen jedoch dazu, dass der Bedarf an Organtransplantaten nur zu einem sehr geringen Teil gedeckt werden kann. Sind Spenderorgane nicht verfügbar, können in einzelnen Fällen lebenswichtige Teilfunktionen, wie beispielsweise die Filtrationsfunktion der Niere durch die Blutreinigung mittels Dialyse ersetzt oder, bei mangelnder Funktion der Bauchspeicheldrüse (Diabetes), durch die Verabreichung von Insulin ein normaler Zustand des Gesamtorganismus auch über Jahre hinweg erhalten werden. Bei der notwendigen lebenslangen Anwendung apparativer oder medikamentöser Therapie können für den Patienten jedoch häufig schwerwiegende, möglicherweise lebensverkürzende Nebenwirkungen entstehen. Daher werden in der Forschung Alternativen gesucht, um die Funktionen des ausgefallenen Organs durch die Implantation von Zellen oder in vitro gezüchteten Geweben möglichst umfassend wieder herzustellen. Dies erfordert biologisch aktive Implantate, welche die für den Stoffwechsel des Organs wichtigen Zellen enthalten und einen organtypischen Stoffwechsel entfalten.

  10. Apport de l'orientation clinique dans le diagnostic des hypertensions arterielles endocriniennes

    PubMed Central

    El Aziz, Siham; Chadli, Asma; Louda, Fatima; El Ghomari, Hassan; Farouqi, Ahmed

    2014-01-01

    L'hypertension artérielle d'origine endocrinienne représente une cause curable d'hypertension artérielle (HTA), ce qui en justifie le dépistage. Une orientation clinique est souhaitable afin de prescrire les bilans adéquats, notamment dans les pays en voie de développement. L'objectif de notre étude est décrire les aspects cliniques des patients ayant une HTA endocrinienne diagnostiquée au CHU de Casablanca. Méthodes: Il s'agit d'une étude descriptive rétrospective de 2004 à 2011, incluant tout patient ayant une HTA endocrinienne (en dehors des dysthyroïdies) admis en Endocrinologie. Les données concernant les facteurs cliniques, paracliniques et thérapeutiques ont été colligées. Au cours de la période étudiée, 53 cas d'HTA endocrinienne ont été admis, avec une age moyen au diagnostic de 39,3 ans et un sex-ratio F/H de 3,9. Trente patients (56.6%) ont un age ont un âge inférieur à 40 ans. On ne retrouve pas d'hérédité tensionelle chez 88.7% des patients. Les étiologies sont le Syndrome de cushing (41.5%), le phéochromocytome (32%), les adénomes somatotropes (15%) et les hyperaldostéronismes primaire (7.5%). L'HTA est essentiellement de grade un ou deux (69.8%), avec un retentissement cardio-vasculaire chez 11 patients (20.7%). Les patients ayant un SC avaient tous des signes cutanés spécifiques. Il s'agissait de sujets jeunes avec plusieurs facteurs de risque cardiovasculaire. Nous avons retrouvé un amaigrissement chez 37.5% des patients ayant un phéochromocytome avec un indice de masse corporel moyen de 20 kg/m2. L'HTA était permanente dans 5 cas de phéochromocytomes. Il n'existait pas d'hypokaliémie chez 50% des patients ayant un hyperaldostéronisme. Les signes cliniques des patients ayant une acromégalie étaient francs, avec un age moyen plus élevé de 50 ans. Nous avons noté une régression de l'HTA chez 59% de ces patients après guérison de l'endocrinopathie en cause. Plusieurs signes cliniques peuvent nous

  11. Fluid Shifts

    NASA Technical Reports Server (NTRS)

    Stenger, M. B.; Hargens, A.; Dulchavsky, S.; Ebert, D.; Lee, S.; Laurie, S.; Garcia, K.; Sargsyan, A.; Martin, D.; Lui, J.; Macias, B.; Arbeille, P.; Danielson, R.; Chang, D.; Gunga, H.; Johnston, S.; Westby, C.; Ribeiro, L.; Ploutz-Snyder, R.; Smith, S.

    2015-01-01

    INTRODUCTION: Mechanisms responsible for the ocular structural and functional changes that characterize the visual impairment and intracranial pressure (ICP) syndrome (VIIP) are unclear, but hypothesized to be secondary to the cephalad fluid shift experienced in spaceflight. This study will relate the fluid distribution and compartmentalization associated with long-duration spaceflight with VIIP symptoms. We also seek to determine whether the magnitude of fluid shifts during spaceflight, as well as the VIIP-related effects of those shifts, can be predicted preflight with acute hemodynamic manipulations, and also if lower body negative pressure (LBNP) can reverse the VIIP effects. METHODS: Physiologic variables will be examined pre-, in- and post-flight in 10 International Space Station crewmembers including: fluid compartmentalization (D2O and NaBr dilution); interstitial tissue thickness (ultrasound); vascular dimensions and dynamics (ultrasound and MRI (including cerebrospinal fluid pulsatility)); ocular measures (optical coherence tomography, intraocular pressure, ultrasound); and ICP measures (tympanic membrane displacement, otoacoustic emissions). Pre- and post-flight measures will be assessed while upright, supine and during 15 deg head-down tilt (HDT). In-flight measures will occur early and late during 6 or 12 month missions. LBNP will be evaluated as a countermeasure during HDT and during spaceflight. RESULTS: The first two crewmembers are in the preflight testing phase. Preliminary results characterize the acute fluid shifts experienced from upright, to supine and HDT postures (increased stroke volume, jugular dimensions and measures of ICP) which are reversed with 25 millimeters Hg LBNP. DISCUSSION: Initial results indicate that acute cephalad fluid shifts may be related to VIIP symptoms, but also may be reversible by LBNP. The effect of a chronic fluid shift has yet to be evaluated. Learning Objectives: Current spaceflight VIIP research is described

  12. Electrorheological fluids

    SciTech Connect

    Halsey, T.C.; Martin, J.E.

    1993-10-01

    An electrorheological fluid is a substance whose form changes in the presence of electric fields. Depending on the strength of the field to which it is subjected, an electrorheological fluid can run freely like water, ooze like honey or solidify like gelatin. Indeed, the substance can switch from ne state to another within a few milliseconds. Electrorheological fluids are easy to make; they consist of microscopic particles suspended in an insulating liquid. Yet they are not ready for most commercial applications. They tend to suffer from a number of problems, including structural weakness as solids, abrasiveness as liquids and chemical breakdown, especially at high temperatures. Automotive engineers could imagine, for instance, constructing an electrorheological clutch. It was also hoped that electrorheological fluids would lead to valveless hydraulic systems, in which solidifying fluid would shut off flow through a thin section of pipe. Electrorheological fluids also offer the possibility of a shock absorber that provides response times of milliseconds and does not require mechanical adjustments. 3 refs.

  13. Reticulation des fibres lignocellulosiques

    NASA Astrophysics Data System (ADS)

    Landrevy, Christel

    Pour faire face à la crise économique la conception de papier à valeur ajoutée est développée par les industries papetières. Le but de se projet est l'amélioration des techniques actuelles de réticulation des fibres lignocellulosiques de la pâte à papier visant à produire un papier plus résistant. En effet, lors des réactions de réticulation traditionnelles, de nombreuses liaisons intra-fibres se forment ce qui affecte négativement l'amélioration anticipée des propriétés physiques du papier ou du matériau produit. Pour éviter la formation de ces liaisons intra-fibres, un greffage sur les fibres de groupements ne pouvant pas réagir entre eux est nécessaire. La réticulation des fibres par une réaction de « click chemistry » appelée cycloaddition de Huisgen entre un azide et un alcyne vrai, catalysée par du cuivre (CuAAC) a été l'une des solutions trouvée pour remédier à ce problème. De plus, une adaptation de cette réaction en milieux aqueux pourrait favoriser son utilisation en milieu industriel. L'étude que nous désirons entreprendre lors de ce projet vise à optimiser la réaction de CuAAC et les réactions intermédiaires (propargylation, tosylation et azidation) sur la pâte kraft, en milieu aqueux. Pour cela, les réactions ont été adaptées en milieu aqueux sur la cellulose microcristalline afin de vérifier sa faisabilité, puis transférée à la pâte kraft et l'influence de différents paramètres comme le temps de réaction ou la quantité de réactifs utilisée a été étudiée. Dans un second temps, une étude des différentes propriétés conférées au papier par les réactions a été réalisée à partir d'une série de tests papetiers optiques et physiques. Mots Clés Click chemistry, Huisgen, CuAAC, propargylation, tosylation, azidation, cellulose, pâte kraft, milieu aqueux, papier.

  14. La diffraction des neutrons et des rayons X pour l'étude structurale des liquides et des verres

    NASA Astrophysics Data System (ADS)

    Fischer, H. E.; Salmon, P. S.; Barnes, A. C.

    2003-02-01

    La compréhension de mainte propriété physique d'un verre ou d'un liquide nécessite la connaissance des facteurs de structure partiels (PSFs) qui décrivent chacun la distribution d'une espèce atomique autour d'une autre. La technique de diffraction des neutrons avec substitution isotopique (NDIS) [1,2,3], ayant bien réussi a déterminer les PSFs de certains composés [4,5], est pourtant restreinte aux isotopes présentant un contraste suffisant en longueur de diffusion. D'un autre cote, la technique de diffusion anomale des rayons X (AXS ou AXD) [6] permet de faire varier la longueur de diffusion d'une espèce atomique pourvu que son énergie d'absorption soit à la fois accessible et suffisamment élevée pour donner un assez grand transfert du moment. La combinaison des techniques de diffraction des neutrons (avec ou sans substitution isotopique) et de diffraction des rayons X (avec ou sans diffusion anomale) peut donc permettre d'obtenir un meilleur contraste en longueurs de diffusion pour un système donné, mais exige une analyse de données plus soignée pour pouvoir bien tenir compte des erreurs systématiques qui sont différentes pour les 2 techniques [7]. Pour les atomes ayant des distributions électroniques quasi-sphériques, e.g. dans le cas d'un alliage liquide, la combinaison des techniques de NDIS et de diffraction des rayons X s'est déjà montrée très avantageuse pour la détermination des PSFs [8,9]. Dans le cas des verres ayant d'importantes liaisons covalentes, l'effective combinaison des 2 techniques peut être moins directe mais facilitée lorsqu'il s'agit des atomes de grand Z [10,11]. Nous présentons ici un sommaire du méthode et quelques exemples des résultats.

  15. Fluid Management System (FMS) fluid systems overview

    NASA Technical Reports Server (NTRS)

    Baird, R. S.

    1990-01-01

    Viewgraphs on fluid management system (FMS) fluid systems overview are presented. Topics addressed include: fluid management system description including system requirements (integrated nitrogen system, integrated water system, and integrated waste gas system) and physical description; and fluid management system evolution.

  16. Missile Aerodynamics (Aerodynamique des Missiles)

    DTIC Science & Technology

    1998-11-01

    guerre froide la production des missiles a baisse’, avec pour consequence une diminution des budgets de d6veloppement. Les nouveaux types de conflits ...Roma) Directeur - Gestion de l’information LUXEMBOURG (Recherche et developpement) - DRDGI 3 Voir Belgique Ministbre de la Difense nationale NORVEGE

  17. Fluid Shifts

    NASA Technical Reports Server (NTRS)

    Stenger, Michael; Hargens, A.; Dulchavsky, S.; Ebert, D.; Lee, S.; Sargsyan, A.; Martin, D.; Lui, J.; Macias, B.; Arbeille, P.; Platts, S.

    2014-01-01

    NASA is focusing on long-duration missions on the International Space Station (ISS) and future exploration-class missions beyond low Earth orbit. Visual acuity changes observed after short-duration missions were largely transient, but more than 30% of ISS astronauts experience more profound, chronic changes with objective structural and functional findings such as papilledema and choroidal folds. Globe flattening, optic nerve sheath dilation, and optic nerve tortuosity also are apparent. This pattern is referred to as the visual impairment and intracranial pressure (VIIP) syndrome. VIIP signs and symptoms, as well as postflight lumbar puncture data, suggest that elevated intracranial pressure (ICP) may be associated with the space flight-induced cephalad fluid shifts, but this hypothesis has not been tested. The purpose of this study is to characterize fluid distribution and compartmentalization associated with long-duration space flight, and to correlate these findings with vision changes and other elements of the VIIP syndrome. We also seek to determine whether the magnitude of fluid shifts during space flight, as well as the VIIP-related effects of those shifts, is predicted by the crewmember's pre-flight condition and responses to acute hemodynamic manipulations (such as head-down tilt). Lastly, we will evaluate the patterns of fluid distribution in ISS astronauts during acute reversal of fluid shifts through application of lower body negative pressure (LBNP) interventions to characterize and explain general and individual responses. We will examine a variety of physiologic variables in 10 long-duration ISS crewmembers using the test conditions and timeline presented in the Figure below. Measures include: (1) fluid compartmentalization (total body water by D2O, extracellular fluid by NaBr, intracellular fluid by calculation, plasma volume by CO rebreathe, interstitial fluid by calculation); (2) forehead/eyelids, tibia, calcaneus tissue thickness (by ultrasound

  18. Fluid Shifts

    NASA Technical Reports Server (NTRS)

    Stenger, M. B.; Hargens, A. R.; Dulchavsky, S. A.; Arbeille, P.; Danielson, R. W.; Ebert, D. J.; Garcia, K. M.; Johnston, S. L.; Laurie, S. S.; Lee, S. M. C.; Liu, J.; Macias, B.; Martin, D. S.; Minkoff, L.; Ploutz-Snyder, R.; Ribeiro, L. C.; Sargsyan, A.; Smith, S. M.

    2017-01-01

    Introduction. NASA's Human Research Program is focused on addressing health risks associated with long-duration missions on the International Space Station (ISS) and future exploration-class missions beyond low Earth orbit. Visual acuity changes observed after short-duration missions were largely transient, but now more than 50 percent of ISS astronauts have experienced more profound, chronic changes with objective structural findings such as optic disc edema, globe flattening and choroidal folds. These structural and functional changes are referred to as the visual impairment and intracranial pressure (VIIP) syndrome. Development of VIIP symptoms may be related to elevated intracranial pressure (ICP) secondary to spaceflight-induced cephalad fluid shifts, but this hypothesis has not been tested. The purpose of this study is to characterize fluid distribution and compartmentalization associated with long-duration spaceflight and to determine if a relation exists with vision changes and other elements of the VIIP syndrome. We also seek to determine whether the magnitude of fluid shifts during spaceflight, as well as any VIIP-related effects of those shifts, are predicted by the crewmember's pre-flight status and responses to acute hemodynamic manipulations, specifically posture changes and lower body negative pressure. Methods. We will examine a variety of physiologic variables in 10 long-duration ISS crewmembers using the test conditions and timeline presented in the figure below. Measures include: (1) fluid compartmentalization (total body water by D2O, extracellular fluid by NaBr, intracellular fluid by calculation, plasma volume by CO rebreathe, interstitial fluid by calculation); (2) forehead/eyelids, tibia, and calcaneus tissue thickness (by ultrasound); (3) vascular dimensions by ultrasound (jugular veins, cerebral and carotid arteries, vertebral arteries and veins, portal vein); (4) vascular dynamics by MRI (head/neck blood flow, cerebrospinal fluid

  19. Médecine des voyages

    PubMed Central

    Aw, Brian; Boraston, Suni; Botten, David; Cherniwchan, Darin; Fazal, Hyder; Kelton, Timothy; Libman, Michael; Saldanha, Colin; Scappatura, Philip; Stowe, Brian

    2014-01-01

    Résumé Objectif Définir la pratique de la médecine des voyages, présenter les éléments fondamentaux d’une consultation complète préalable aux voyages à des voyageurs internationaux et aider à identifier les patients qu’il vaudrait mieux envoyer en consultation auprès de professionnels de la médecine des voyages. Sources des données Les lignes directrices et les recommandations sur la médecine des voyages et les maladies liées aux voyages publiées par les autorités sanitaires nationales et internationales ont fait l’objet d’un examen. Une recension des ouvrages connexes dans MEDLINE et EMBASE a aussi été effectuée. Message principal La médecine des voyages est une spécialité très dynamique qui se concentre sur les soins préventifs avant un voyage. Une évaluation exhaustive du risque pour chaque voyageur est essentielle pour mesurer avec exactitude les risques particuliers au voyageur, à son itinéraire et à sa destination et pour offrir des conseils sur les interventions les plus appropriées en gestion du risque afin de promouvoir la santé et prévenir les problèmes médicaux indésirables durant le voyage. Des vaccins peuvent aussi être nécessaires et doivent être personnalisés en fonction des antécédents d’immunisation du voyageur, de son itinéraire et du temps qu’il reste avant son départ. Conclusion La santé et la sécurité d’un voyageur dépendent du degré d’expertise du médecin qui offre le counseling préalable à son voyage et les vaccins, au besoin. On recommande à ceux qui donnent des conseils aux voyageurs d’être conscients de l’ampleur de cette responsabilité et de demander si possible une consultation auprès de professionnels de la médecine des voyages pour tous les voyageurs à risque élevé.

  20. Calendar of Selected Aeronautical and Space Meetings (Calendrier des Manifestations Aeronautiques et Spatiales (Selection))

    DTIC Science & Technology

    1989-01-01

    figurant dans la rubrique 06 (( Thermodynamique , Combustion, Propulsion et Energ6tique >> traite d’A6ro- NOTA I’AGARD ne peut se charger de...Dynamiquc des Fluides et Acoustique 30 05 - Navigation, Guidage et Pilotage 38 06 - Thermodynamique , Combustion, Propulsion ct Energ~tique 45 (07

  1. Fluid Mechanics

    NASA Astrophysics Data System (ADS)

    Pnueli, David; Gutfinger, Chaim

    1997-01-01

    This text is intended for the study of fluid mechanics at an intermediate level. The presentation starts with basic concepts, in order to form a sound conceptual structure that can support engineering applications and encourage further learning. The presentation is exact, incorporating both the mathematics involved and the physics needed to understand the various phenomena in fluid mechanics. Where a didactical choice must be made between the two, the physics prevails. Throughout the book the authors have tried to reach a balance between exact presentation, intuitive grasp of new ideas, and creative applications of concepts. This approach is reflected in the examples presented in the text and in the exercises given at the end of each chapter. Subjects treated are hydrostatics, viscous flow, similitude and order of magnitude, creeping flow, potential flow, boundary layer flow, turbulent flow, compressible flow, and non-Newtonian flows. This book is ideal for advanced undergraduate students in mechanical, chemical, aerospace, and civil engineering. Solutions manual available.

  2. Fluid extraction

    DOEpatents

    Wai, Chien M.; Laintz, Kenneth E.

    1999-01-01

    A method of extracting metalloid and metal species from a solid or liquid material by exposing the material to a supercritical fluid solvent containing a chelating agent is described. The chelating agent forms chelates that are soluble in the supercritical fluid to allow removal of the species from the material. In preferred embodiments, the extraction solvent is supercritical carbon dioxide and the chelating agent is a fluorinated .beta.-diketone. In especially preferred embodiments the extraction solvent is supercritical carbon dioxide, and the chelating agent comprises a fluorinated .beta.-diketone and a trialkyl phosphate, or a fluorinated .beta.-diketone and a trialkylphosphine oxide. Although a trialkyl phosphate can extract lanthanides and actinides from acidic solutions, a binary mixture comprising a fluorinated .beta.-diketone and a trialkyl phosphate or a trialkylphosphine oxide tends to enhance the extraction efficiencies for actinides and lanthanides. The method provides an environmentally benign process for removing contaminants from industrial waste without using acids or biologically harmful solvents. The method is particularly useful for extracting actinides and lanthanides from acidic solutions. The chelate and supercritical fluid can be regenerated, and the contaminant species recovered, to provide an economic, efficient process.

  3. Towards a Dynamic DES model

    NASA Astrophysics Data System (ADS)

    Subbareddy, Pramod; Candler, Graham

    2009-11-01

    Hybrid RANS/LES methods are being increasingly used for turbulent flow simulations in complex geometries. Spalart's detached eddy simulation (DES) model is one of the more popular ones. We are interested in examining the behavior of the Spalart-Allmaras (S-A) Detached Eddy Simulation (DES) model in its ``LES mode.'' The role of the near-wall functions present in the equations is analyzed and an explicit analogy between the S-A and a one-equation LES model based on the sub-grid kinetic energy is presented. A dynamic version of the S-A DES model is proposed based on this connection. Validation studies and results from DES and LES applications will be presented and the effect of the proposed modification will be discussed.

  4. Impact of Materials Defects on Engine Structures Integrity (L’Impact des Defauts des Materiaux sur l’Integrite des Structures des Moteurs)

    DTIC Science & Technology

    1993-04-01

    participants ont fait le point des aspects traitement et contr6le des mat~riaux. en mettant I’accent sur les materiaux constitutifs des disques moteur en...adapte. Pour le physicien. un -d~faur’" peut tres bien se resumer A une imperfection de Ia structure rericulaire d’un materiau. En science des materiaux ... materiaux sur l~integrite des structures des moteurs Defence Research Ag~ency Matenials & Structures Department Farnborough. Hants GUt 14 fITD Rovaume-Uni

  5. Drilling fluid

    SciTech Connect

    Russell, J.A.; Patel, B.B.

    1987-11-03

    A drilling fluid additive mixture is described consisting essentially of a sulfoalkylated tannin in admixture with a non-sulfoalkylated alkali-solubilized lignite wherein the weight ratio of the sulfoalkylated tannin to the non-sulfoalkylated lignite is in the range from about 2:1 to about 1:1. The sulfoalkylated tannin has been sulfoalkylated with at least one -(C(R-)/sub 2/-SO/sub 3/M side chain, wherein each R is selected from the group consisting of hydrogen and alkyl radicals containing from 1 to about 5 carbon atoms, and M is selected from the group consisting of ammonium and the alkali metals.

  6. Peste des petits ruminants

    PubMed Central

    Parida, S.; Muniraju, M.; Mahapatra, M.; Muthuchelvan, D.; Buczkowski, H.; Banyard, A.C.

    2015-01-01

    Peste des petits ruminants virus causes a highly infectious disease of small ruminants that is endemic across Africa, the Middle East and large regions of Asia. The virus is considered to be a major obstacle to the development of sustainable agriculture across the developing world and has recently been targeted by the World Organisation for Animal Health (OIE) and the Food and Agriculture Organisation (FAO) for eradication with the aim of global elimination of the disease by 2030. Fundamentally, the vaccines required to successfully achieve this goal are currently available, but the availability of novel vaccine preparations to also fulfill the requisite for differentiation between infected and vaccinated animals (DIVA) may reduce the time taken and the financial costs of serological surveillance in the later stages of any eradication campaign. Here, we overview what is currently known about the virus, with reference to its origin, updated global circulation, molecular evolution, diagnostic tools and vaccines currently available to combat the disease. Further, we comment on recent developments in our knowledge of various recombinant vaccines and on the potential for the development of novel multivalent vaccines for small ruminants. PMID:26443889

  7. Peste des petits ruminants.

    PubMed

    Parida, S; Muniraju, M; Mahapatra, M; Muthuchelvan, D; Buczkowski, H; Banyard, A C

    2015-12-14

    Peste des petits ruminants virus causes a highly infectious disease of small ruminants that is endemic across Africa, the Middle East and large regions of Asia. The virus is considered to be a major obstacle to the development of sustainable agriculture across the developing world and has recently been targeted by the World Organisation for Animal Health (OIE) and the Food and Agriculture Organisation (FAO) for eradication with the aim of global elimination of the disease by 2030. Fundamentally, the vaccines required to successfully achieve this goal are currently available, but the availability of novel vaccine preparations to also fulfill the requisite for differentiation between infected and vaccinated animals (DIVA) may reduce the time taken and the financial costs of serological surveillance in the later stages of any eradication campaign. Here, we overview what is currently known about the virus, with reference to its origin, updated global circulation, molecular evolution, diagnostic tools and vaccines currently available to combat the disease. Further, we comment on recent developments in our knowledge of various recombinant vaccines and on the potential for the development of novel multivalent vaccines for small ruminants.

  8. Les carcinomes epidermoïdes du scrotum: à propos de 7 cas avec revue de la litterature

    PubMed Central

    Halfya, Ayoub; Elmortaji, Khalid; Redouane, Rabii; fethi, Meziane; Rafik, Amine; Mohamed, Ezzoubi; Abdessamad, Chlihi

    2015-01-01

    Quoique rare le carcinome épidermoïde du scrotum a un mauvais pronostic. Les Carcinomes du scrotum induite et - liées au travail sont moins fréquentes en raison d'une meilleure hygiène, vêtements de protection, et la sensibilisation de la cancérogénicité des huiles industrielles. L’épidémie à l'HPV a induit une augmentation de l'incidence. Le traitement de dépend toujours exérèse locale de la lésion primaire. La radiothérapie a peu de bénéfice thérapeutique dans le traitement d'un carcinome épidermoïde du scrotum. La bléomycine peut être utile comme traitement adjuvant pour les maladies ilio-inguinal généralisée avant la tentative exérèse, même si cela n'a pas encore été prouvé. Entre janvier 2011 au 1er janvier 2013, 7 patients atteints de carcinome épidermoïde ont été pris en charge, Trois patients ont présenté une localisation ganglionnaire. Les sept patients ont eu un traitement chirurgical par exérèse large avec reconstruction, Deux patients ont été adressé pour chimiothérapie.2 patients ont présenté une récidive, dont un est décédé. PMID:26113906

  9. Etude des Abondances de MG et de fe dans la Composante Stellaire des Disques des Galaxies Spirales

    NASA Astrophysics Data System (ADS)

    Beauchamp, Dominique

    Je presente ici une technique d'observation par imagerie des disques stellaires des galaxies spirales. Je tente, a l'aide d'un modele evolutif multiphase, de determiner les abondances de fer et de magnesium dans les disques. Dans ce but, je mesure les indices Mg2 et Fe5270 du systeme de Lick. Ces elements representent un choix judicieux d'indicateurs car ils sont formes par des supernovae de deux types differents ayant des durees de vie differentes. Le rapport d'abondances de ces deux elements est un indicateur du taux de formation des populations stellaires. Je decris, en premier lieu, les observations, la technique de mesure, ainsi que son application. J'analyse ensuite les indices mesures. A partir du modele multiphase, j'explore differents parametres physiques des spirales comme le taux de formation stellaire, l'evolution des abondances, les effets possibles de la presence de la barre, etc.

  10. Thermophysical Properties of Fluids and Fluid Mixtures

    SciTech Connect

    Sengers, Jan V.; Anisimov, Mikhail A.

    2004-05-03

    The major goal of the project was to study the effect of critical fluctuations on the thermophysical properties and phase behavior of fluids and fluid mixtures. Long-range fluctuations appear because of the presence of critical phase transitions. A global theory of critical fluctuations was developed and applied to represent thermodynamic properties and transport properties of molecular fluids and fluid mixtures. In the second phase of the project, the theory was extended to deal with critical fluctuations in complex fluids such as polymer solutions and electrolyte solutions. The theoretical predictions have been confirmed by computer simulations and by light-scattering experiments. Fluctuations in fluids in nonequilibrium states have also been investigated.

  11. Classification of 8 DES Supernova with OzDES

    NASA Astrophysics Data System (ADS)

    King, A.; Moller, A.; Sommer, N. E.; Tucker, B. E.; Childress, M. J.; Lewis, G. F.; Lidman, C.; OâNeill, C.; Casas, R.; Castander, F. J.; Desai, S.; Paech, K.; Smith, R. C.; Schubnell, M.; Kessler, R.; Lasker, J.; Scolnic, D.; Brout, D. J.; Gladney, L.; Sako, M.; Wolf, R. C.; Brown, P. J.; Krisciunas, K.; Suntzeff, N.; Nichol, R.; Papadopoulos, A.; D'Andrea, C.; Prajs, S.; Smith, M.; Sullivan, M.; Maartens, R.; Gupta, R.; Kovacs, E.; Kuhlmann, S.; Spinka, H.; Ahn, E.; Finley, D. A.; Frieman, J.; Marriner, J.; Wester, W.; Aldering, G.; Kim, A. G.; Thomas, R. C.; Barbary, K.; Bloom, J. S.; Goldstein, D.; Nugent, P.; Perlmutter, S.; Foley, R. J.; Pan, Y.-C.

    2016-09-01

    We report new spectroscopic classifications by OzDES of supernovae discovered by the Dark Energy Survey (ATEL #4668). The spectra (370-885nm) were obtained with the AAOmega Spectrograph (Saunders et al. 2004, SPIE, 5492, 389) and the 2dF fibre positioner at the Anglo-Australian Telescope (AAT).

  12. Classification of 17 DES Supernova with OzDES

    NASA Astrophysics Data System (ADS)

    Hoormann, J. K.; Asorey, J.; Carollo, D.; Moller, A.; Sharp, R.; Sommer, N. E.; Tucker, B. E.; Zhang, B.; Lidman, C.; Brout, D. J.; D'Andrea, C.; Gladney, L.; March, M.; Sako, M.; Wolf, R. C.; Brown, P. J.; Krisciunas, K.; Suntzeff, N.; Macaulay, E.; Nichol, R.; Childress, M.; Prajs, S.; Smith, M.; Sullivan, M.; Maartens, R.; Kovacs, E.; Kuhlmann, S.; Spinka, H.; Ahn, E.; Finley, D. A.; Frieman, J.; Marriner, J.; Wester, W.; Aldering, G.; Gupta, R.; Kim, A. G.; Thomas, R. C.; Barbary, K.; Bloom, J. S.; Goldstein, D.; Nugent, P.; Perlmutter, S.; Foley, R. J.; Pan, Y.-C.; Casas, R.; Castander, F. J.; Papadopoulos, A.; Morganson, E.; Desai, S.; Paech, K.; Smith, R. C.; Schubnell, M.; Yuan, F.; Davis, T. M.; Hinton, S.; Muthukrishna, D.; Parkinson, D.; Lewis, G. F.; Uddin, S.; Kessler, R.; Lasker, J.; Scolnic, D.

    2016-12-01

    We report new spectroscopic classifications by OzDES of supernovae discovered by the Dark Energy Survey (ATEL #4668). The spectra (370-885nm) were obtained with the AAOmega Spectrograph (Saunders et al. 2004, SPIE, 5492, 389) and the 2dF fibre positioner at the Anglo-Australian Telescope (AAT).

  13. Classification of 13 DES supernova with OzDES

    NASA Astrophysics Data System (ADS)

    Sommer, N.; Tucker, B. E.; Moller, A.; Zhang, B.; Macualay, E.; Lidman, C.; Gshwend, J.; Martini, P.; Foley, R. J.; Pan, Y.-C.; Casas, R.; Castander, F. J.; Desai, S.; Paech, K.; Smith, R. C.; Schubnell, M.; Kessler, R.; Lasker, J.; Scolnic, D.; Brout, D. J.; Gladney, L.; Sako, M.; Wolf, R. C.; Brown, P. J.; Krisciunas, K.; Suntzeff, N.; Nichol, R.; Papadopoulos, A.; Childress, M.; D'Andrea, C.; Prajs, S.; Smith, M.; Sullivan, M.; Maartens, R.; Gupta, R.; Kovacs, E.; Kuhlmann, S.; Spinka, H.; Ahn, E.; Finley, D. A.; Frieman, J.; Marriner, J.; Wester, W.; Aldering, G.; Kim, A. G.; Thomas, R. C.; Barbary, K.; Bloom, J. S.; Goldstein, D.; Nugent, P.; Perlmutter, S.

    2016-09-01

    We report new spectroscopic classifications by OzDES of supernovae discovered by the Dark Energy Survey (ATEL #4668). The spectra (370-885nm) were obtained with the AAOmega Spectrograph (Saunders et al. 2004, SPIE, 5492, 389) and the 2dF fibre positioner at the Anglo-Australian Telescope (AAT).

  14. Classification of 11 DES supernova with OzDES

    NASA Astrophysics Data System (ADS)

    Sharp, R.; Zhang, B.; Sommer, N. E.; Tucker, B. E.; Lidman, C.; Davis, T. M.; Asorey, J.; Mould, J.; Smith, M.; Macaulay, E.; Nichol, R.; Childress, M.; Prajs, S.; Sullivan, M.; Maartens, R.; Kovacs, E.; Kuhlmann, S.; Spinka, H.; Ahn, E.; Finley, D. A.; Frieman, J.; Marriner, J.; Wester, W.; Aldering, G.; Gupta, R.; Kim, A. G.; Thomas, R. C.; Barbary, K.; Bloom, J. S.; Goldstein, D.; Nugent, P.; Perlmutter, S.; Foley, R. J.; Pan, Y.-C.; Casas, R.; Castander, F. J.; Papadopoulos, A.; Morganson, E.; Desai, S.; Paech, K.; Smith, R. C.; Schubnell, M.; Carollo, D.; Moller, A.; Yuan, F.; Hinton, S.; Muthukrishna, D.; Parkinson, D.; Lewis, G. F.; Uddin, S.; Kessler, R.; Lasker, J.; Scolnic, D.; Brout, D. J.; D'Andrea, C.; Gladney, L.; March, M.; Sako, M.; Wolf, R. C.; Brown, P. J.; Krisciunas, K.; Suntzeff, N.

    2017-01-01

    We report new spectroscopic classifications by OzDES of supernovae discovered by the Dark Energy Survey (ATEL #4668). The spectra (370-885nm) were obtained with the AAOmega Spectrograph (Saunders et al. 2004, SPIE, 5492, 389) and the 2dF fibre positioner at the Anglo-Australian Telescope (AAT).

  15. Classification of 2 DES supernova with OzDES

    NASA Astrophysics Data System (ADS)

    O'Neill, C. R.; Moller, A.; Sommer, N. E.; Tucker, B. E.; Childress, M. J.; Lewis, G. F.; Lidman, C.; Desai, S.; Paech, K.; Smith, R. C.; Schubnell, M.; Kessler, R.; Lasker, J.; Scolnic, D.; Brout, D. J.; D'Andrea, C.; Gladney, L.; March, M.; Sako, M.; Wolf, R. C.; Brown, P. J.; Krisciunas, K.; Suntzeff, N.; Macaulay, E.; Nichol, R.; Prajs, S.; Smith, M.; Sullivan, M.; Maartens, R.; Kovacs, E.; Kuhlmann, S.; Spinka, H.; Ahn, E.; Finley, D. A.; Frieman, J.; Marriner, J.; Wester, W.; Aldering, G.; Kim, A. G.; Thomas, R. C.; Barbary, K.; Bloom, J. S.; Goldstein, D.; Gupta, R.; Nugent, P.; Perlmutter, S.; Foley, R. J.; Pan, Y.-C.; Casas, R.; Castander, F. J.; Papadopoulos, A.; Morganson, E.

    2016-10-01

    We report new spectroscopic classifications by OzDES of supernovae discovered by the Dark Energy Survey (ATEL #4668). The spectra (370-885nm) were obtained with the AAOmega Spectrograph (Saunders et al. 2004, SPIE, 5492, 389) and the 2dF fibre positioner at the Anglo-Australian Telescope (AAT).

  16. Classification of 3 DES Supernovae with OzDES

    NASA Astrophysics Data System (ADS)

    Moller, A.; Tucker, B. E.; Yuan, F.; Lewis, G.; Lidman, C.; Macaulay, E.; Nichol, R.; Papadopoulos, A.; Childress, M.; D'Andrea, C.; Smith, M.; Sullivan, M.; Maartens, R.; Gupta, R.; Kovacs, E.; Kuhlmann, S.; Spinka, H.; Ahn, E.; Finley, D. A.; Frieman, J.; Marriner, J.; Wester, W.; Aldering, G.; Kim, A. G.; Thomas, R. C.; Barbary, K.; Bloom, J. S.; Goldstein, D.; Nugent, P.; Perlmutter, S.; Foley, R. J.; Pan, Y.-C.; Casas, R.; Castander, F. J.; Desai, S.; Paech, K.; Smith, R. C.; Schubnell, M.; Kessler, R.; Lasker, J.; Scolnic, D.; Brout, D. J.; Gladney, L.; Sako, M.; Wolf, R. C.; Brown, P. J.; Krisciunas, K.; Suntzeff, N.

    2016-02-01

    We report new spectroscopic classifications by OzDES of supernovae discovered by the Dark Energy Survey (ATEL #4668). The spectra (370-885nm) were obtained with the AAOmega Spectrograph (Saunders et al. 2004, SPIE, 5492, 389) and the 2dF fibre positioner at the Anglo-Australian Telescope (AAT).

  17. Classification of 20 DES Supernova with OzDES

    NASA Astrophysics Data System (ADS)

    Davis, T. M.; Kim, A. G.; Macualay, E.; Lidman, C.; Sharp, R.; Tucker, B. E.; Yuan, F.; Zhang, B.; Lewis, G. F.; Sommer, N. E.; Martini, P.; Mould, J.; Ahn, E.; Finley, D. A.; Frieman, J.; Marriner, J.; Wester, W.; Aldering, G.; Thomas, R. C.; Barbary, K.; Bloom, J. S.; Goldstein, D.; Nugent, P.; Perlmutter, S.; Foley, R. J.; Pan, Y.-C.; Casas, R.; Castander, F. J.; Desai, S.; Paech, K.; Smith, R. C.; Schubnell, M.; Kessler, R.; Lasker, J.; Scolnic, D.; Brout, D. J.; Gladney, L.; Sako, M.; Wolf, R. C.; Brown, P. J.; Krisciunas, K.; Suntzeff, N.; Nichol, R.; Papadopoulos, A.; Childress, M.; D'Andrea, C.; Smith, M.; Sullivan, M.; Maartens, R.; Gupta, R.; Kovacs, E.; Kuhlmann, S.; Spinka, H.

    2015-12-01

    We report new spectroscopic classifications by OzDES of supernovae discovered by the Dark Energy Survey (ATEL #4668). The spectra (370-885nm) were obtained with the AAOmega Spectrograph (Saunders et al. 2004, SPIE, 5492, 389) and the 2dF fibre positioner at the Anglo-Australian Telescope (AAT).

  18. Classification of 14 DES Supernova with OzDES

    NASA Astrophysics Data System (ADS)

    Tucker, B. E.; Sharp, R.; Yuan, F.; Zhang, B.; Lidman, C.; Davis, T. M.; Hinton, S.; Mould, J.; Smith, R. C.; Schubnell, M.; Kessler, R.; Scolnic, D.; Covarrubias, R. A.; Brout, D. J.; Fischer, J. A.; Gladney, L.; March, M.; Sako, M.; Wolf, R. C.; Brown, P. J.; Krisciunas, K.; Suntzeff, N.; Nichol, R.; Papadopoulos, A.; D'Andrea, C.; Smith, M.; Sullivan, M.; Childress, M.; Maartens, R.; Gupta, R.; Kovacs, E.; Kuhlmann, S.; Spinka, H.; Ahn, E.; Finley, D. A.; Frieman, J.; Marriner, J.; Wester, W.; Aldering, G.; Kim, A. G.; Thomas, R. C.; Barbary, K.; Bloom, J. S.; Goldstein, D.; Nugent, P.; Perlmutter, S.; Foley, R. J.; Castander, F. J.; Desai, S.; Paech, K.

    2015-10-01

    We report new spectroscopic classifications by OzDES of supernovae discovered by the Dark Energy Survey. The spectra (370-885nm) were obtained with the AAOmega Spectrograph (Saunders et al. 2004, SPIE, 5492, 389) and the 2dF fibre positioner at the Anglo-Australian Telescope (AAT).

  19. Classification of 4 DES supernovae by OzDES

    NASA Astrophysics Data System (ADS)

    Glazebrook, K.; Amon, A.; Lidman, C.; Martini, P.; Tucker, B. E.; Yuan, F.; Aldering, G.; Kim, A. G.; Thomas, R. C.; Barbary, K.; Bloom, J. S.; Goldstein, D.; Nugent, P.; Perlmutter, S.; Foley, R. J.; Pan, Y.-C.; Casas, R.; Castander, F. J.; Desai, S.; Paech, K.; Smith, R. C.; Schubnell, M.; Kessler, R.; Lasker, J.; Scolnic, D.; Brout, D. J.; Gladney, L.; Sako, M.; Wolf, R. C.; Brown, P. J.; Krisciunas, K.; Suntzeff, N.; Nichol, R.; Papadopoulos, A.; Childress, M.; D'Andrea, C.; Smith, M.; Sullivan, M.; Maartens, R.; Gupta, R.; Kovacs, E.; Kuhlmann, S.; Spinka, H.; Ahn, E.; Finley, D. A.; Frieman, J.; Marriner, J.; Wester, W.

    2015-12-01

    We report new spectroscopic classifications by OzDES of supernovae discovered by the Dark Energy Survey (ATEL #4668). The spectra (370-885nm) were obtained with the AAOmega Spectrograph (Saunders et al. 2004, SPIE, 5492, 389) and the 2dF fibre positioner at the Anglo-Australian Telescope (AAT).

  20. Classification of 6 DES Supernova with OzDES

    NASA Astrophysics Data System (ADS)

    Lewis, G. F.; Mould, J.; Lidman, C.; Tucker, B. E.; Sharp, R.; Yuan, F.; Martini, P.; Kessler, R.; Scolnic, D.; Covarrubias, R. A.; Brout, D. J.; Fischer, J. A.; Gladney, L.; March, M.; Sako, M.; Wolf, R. C.; Brown, P. J.; Krisciunas, K.; Suntzeff, N.; Nichol, R.; Papadopoulos, A.; D'Andrea, C.; Smith, M.; Sullivan, M.; Childress, M.; Maartens, R.; Gupta, R.; Kovacs, E.; Kuhlmann, S.; Spinka, H.; Ahn, E.; Finley, D. A.; Frieman, J.; Marriner, J.; Wester, W.; Aldering, G.; Kim, A. G.; Thomas, R. C.; Barbary, K.; Bloom, J. S.; Goldstein, D.; Nugent, P.; Perlmutter, S.; Foley, R. J.; Casas, R.; Castander, F. J.; Desai, S.; Paech, K.; Smith, R. C.; Schubnell, M.

    2015-10-01

    We report new spectroscopic classifications by OzDES of supernovae discovered by the Dark Energy Survey (ATEL #4668). The spectra (370-885nm) were obtained with the AAOmega Spectrograph (Saunders et al. 2004, SPIE, 5492, 389) and the 2dF fibre positioner at the Anglo-Australian Telescope (AAT).

  1. Classification of 15 DES supernovae by OzDES

    NASA Astrophysics Data System (ADS)

    Yuan, F.; Tucker, B. E.; Lidman, C.; Martini, P.; Gshwend, Julia; Moller, A.; Zhang, B.; Smith, R. C.; Schubnell, M.; Kessler, R.; Lasker, J.; Scolnic, D.; Brout, D. J.; Gladney, L.; Sako, M.; Wolf, R. C.; Brown, P. J.; Krisciunas, K.; Suntzeff, N.; Nichol, R.; Papadopoulos, A.; Childress, M.; D'Andrea, C.; Smith, M.; Sullivan, M.; Maartens, R.; Gupta, R.; Kovacs, E.; Kuhlmann, S.; Spinka, H.; Ahn, E.; Finley, D. A.; Frieman, J.; Marriner, J.; Wester, W.; Aldering, G.; Kim, A. G.; Thomas, R. C.; Barbary, K.; Bloom, J. S.; Goldstein, D.; Nugent, P.; Perlmutter, S.; Foley, R. J.; Pan, Y.-C.; Casas, R.; Castander, F. J.; Desai, S.; Paech, K.

    2015-12-01

    We report new spectroscopic classifications by OzDES of supernovae discovered by the Dark Energy Survey (ATEL #4668). The spectra (370-885nm) were obtained with the AAOmega Spectrograph (Saunders et al. 2004, SPIE, 5492, 389) and the 2dF fibre positioner at the Anglo-Australian Telescope (AAT).

  2. Classification of 17 DES supernova with OzDES

    NASA Astrophysics Data System (ADS)

    Mudd, D.; Martini, P.; Lewis, G. F.; Moller, A.; Sharp, R. G.; Sommer, N. E.; Tucker, B. E.; Yuan, F.; Zhang, B.; Asorey, J.; Davis, T. M.; Hinton, S.; Muthukrishna, D.; Parkinson, D.; Carnero, A.; King, A.; Lidman, C.; Webb, S.; Uddin, S.; Kessler, R.; Lasker, J.; Scolnic, D.; Brout, D. J.; D'Andrea, C.; Gladney, L.; March, M.; Sako, M.; Wolf, R. C.; Brown, P. J.; Krisciunas, K.; Suntzeff, N.; Macaulay, E.; Nichol, R.; Childress, M.; Prajs, S.; Smith, M.; Sullivan, M.; Maartens, R.; Kovacs, E.; Kuhlmann, S.; Spinka, H.; Ahn, E.; Finley, D. A.; Frieman, J.; Marriner, J.; Wester, W.; Aldering, G.; Gupta, R.; Kim, A. G.; Thomas, R. C.; Barbary, K.; Bloom, J. S.; Goldstein, D.; Nugent, P.; Perlmutter, S.; Foley, R. J.; Pan, Y.-C.; Casas, R.; Castander, F. J.; Papadopoulos, A.; Morganson, E.; Desai, S.; Paech, K.; Smith, R. C.; Schubnell, M.

    2016-11-01

    We report new spectroscopic classifications by OzDES of supernovae discovered by the Dark Energy Survey (ATEL #4668). The spectra (370-885nm) were obtained with the AAOmega Spectrograph (Saunders et al. 2004, SPIE, 5492, 389) and the 2dF fibre positioner at the Anglo-Australian Telescope (AAT).

  3. Magnetized drive fluids

    SciTech Connect

    Rosensweig, R.E.; Zahn, M.

    1986-04-01

    A process is described for recovering a first fluid from a porous subterranean formation which comprises injecting a displacement fluid in an effective amount to displace the first fluid, injecting a ferrofluid, applying a magnetic field containing a gradient of field intensity within the formation, driving the displacement fluid through the formation with the ferrofluid and recovering first fluid.

  4. Fluid sampling tool

    DOEpatents

    Garcia, Anthony R.; Johnston, Roger G.; Martinez, Ronald K.

    2000-01-01

    A fluid-sampling tool for obtaining a fluid sample from a container. When used in combination with a rotatable drill, the tool bores a hole into a container wall, withdraws a fluid sample from the container, and seals the borehole. The tool collects fluid sample without exposing the operator or the environment to the fluid or to wall shavings from the container.

  5. Latina Voices of Des Moines.

    ERIC Educational Resources Information Center

    Taylor, P. Dawn

    This dissertation examines the lives of Hispanic women living in Des Moines and includes their views of problems and opportunities involved in living in that city. Interviews were conducted with 24 Latino women over the age of 17 who had been in the area for over 2 years. Findings indicate that learning to speak English was the single most…

  6. Fluid Inclusion Gas Analysis

    DOE Data Explorer

    Dilley, Lorie

    2013-01-01

    Fluid inclusion gas analysis for wells in various geothermal areas. Analyses used in developing fluid inclusion stratigraphy for wells and defining fluids across the geothermal fields. Each sample has mass spectrum counts for 180 chemical species.

  7. L'astronomie des Anciens

    NASA Astrophysics Data System (ADS)

    Nazé, Yaël

    2009-04-01

    Quelle que soit la civilisation à laquelle il appartient, l'être humain cherche dans le ciel des réponses aux questions qu'il se pose sur son origine, son avenir et sa finalité. Le premier mérite de ce livre est de nous rappeler que l'astronomie a commencé ainsi à travers les mythes célestes imaginés par les Anciens pour expliquer l'ordre du monde et la place qu'ils y occupaient. Mais les savoirs astronomiques passés étaient loin d'être négligeables et certainement pas limités aux seuls travaux des Grecs : c'est ce que l'auteur montre à travers une passionnante enquête, de Stonehenge à Gizeh en passant par Pékin et Mexico, fondée sur l'étude des monuments anciens et des sources écrites encore accessibles. Les tablettes mésopotamiennes, les annales chinoises, les chroniques médiévales, etc. sont en outre d'une singulière utilité pour les astronomes modernes : comment sinon remonter aux variations de la durée du jour au cours des siècles, ou percer la nature de l'explosion qui a frappé tant d'observateurs en 1054 ? Ce livre offre un voyage magnifiquement illustré à travers les âges, entre astronomie et archéologie.

  8. Multistatic Surveillance and Reconnaissance: Sensor, Signals and Data Fusion (Surveillance et Reconnaissance Multistatiques : Fusion des capteurs, des signaux et des donnees)

    DTIC Science & Technology

    2009-04-01

    capteurs , des signaux et des données) Research and Technology Organisation (NATO) BP 25, F-92201 Neuilly-sur-Seine Cedex, France RTO-EN-SET-133...Multistatiques : Fusion des capteurs , des signaux et des données) The material in this publication was assembled to support a Lecture Series under the...Surveillance et Reconnaissance Multistatiques : Fusion des capteurs , des signaux et des données (RTO-EN-SET-133) Synthèse Les systèmes radar

  9. Attitudes Sociales et Intellectuelles et Valeurs a Developper dans L'Enseignement Quebecois des Sciences Humaines au Primaire: Une Analyse des Propositions du Programme D'Etudes (Social and Intellectual Attitudes and Values to Be Developed in Social Science Instruction in the Elementary Grades in Quebec: An Analysis of the Proposals of the Program of Study).

    ERIC Educational Resources Information Center

    Laforest, Mario; Lenoir, Yves

    1994-01-01

    Discusses Quebec's elementary school social studies program, which aims to promote the development of politically correct social attitudes and scientifically correct intellectual attitudes. Suggests that, under the cover of a developmental approach to "savoir-etre" ("knowing how to be"), the program supports a technobehaviorist…

  10. Active Control Technology for Enhanced Performance Operational Capabilities of Military Aircraft, Land Vehicles and Sea Vehicles (Technologies des systemes a commandes actives pour l’amelioration des performances operationnelles des aeronefs militaires, des vehicules terrestres et des vehicules maritimes)

    DTIC Science & Technology

    2001-06-01

    d’améliorer le comportement global des systèmes et des sous- systèmes. Il s’agit de matériaux intelligents, de technologies informatiques, de capteurs ...des servocommandes rapides et fiables, ainsi que des capteurs de fonctionnement fiable même dans des environnements défavorables, et en particulier...des sous-systèmes. Il s’agit de matériaux intelligents, de technologies de fabrication novatrices, de technologies informatiques, de capteurs et de

  11. Fluid mechanics in fluids at rest.

    PubMed

    Brenner, Howard

    2012-07-01

    Using readily available experimental thermophoretic particle-velocity data it is shown, contrary to current teachings, that for the case of compressible flows independent dye- and particle-tracer velocity measurements of the local fluid velocity at a point in a flowing fluid do not generally result in the same fluid velocity measure. Rather, tracer-velocity equality holds only for incompressible flows. For compressible fluids, each type of tracer is shown to monitor a fundamentally different fluid velocity, with (i) a dye (or any other such molecular-tagging scheme) measuring the fluid's mass velocity v appearing in the continuity equation and (ii) a small, physicochemically and thermally inert, macroscopic (i.e., non-Brownian), solid particle measuring the fluid's volume velocity v(v). The term "compressibility" as used here includes not only pressure effects on density, but also temperature effects thereon. (For example, owing to a liquid's generally nonzero isobaric coefficient of thermal expansion, nonisothermal liquid flows are to be regarded as compressible despite the general perception of liquids as being incompressible.) Recognition of the fact that two independent fluid velocities, mass- and volume-based, are formally required to model continuum fluid behavior impacts on the foundations of contemporary (monovelocity) fluid mechanics. Included therein are the Navier-Stokes-Fourier equations, which are now seen to apply only to incompressible fluids (a fact well-known, empirically, to experimental gas kineticists). The findings of a difference in tracer velocities heralds the introduction into fluid mechanics of a general bipartite theory of fluid mechanics, bivelocity hydrodynamics [Brenner, Int. J. Eng. Sci. 54, 67 (2012)], differing from conventional hydrodynamics in situations entailing compressible flows and reducing to conventional hydrodynamics when the flow is incompressible, while being applicable to both liquids and gases.

  12. Fluid mechanics in fluids at rest

    NASA Astrophysics Data System (ADS)

    Brenner, Howard

    2012-07-01

    Using readily available experimental thermophoretic particle-velocity data it is shown, contrary to current teachings, that for the case of compressible flows independent dye- and particle-tracer velocity measurements of the local fluid velocity at a point in a flowing fluid do not generally result in the same fluid velocity measure. Rather, tracer-velocity equality holds only for incompressible flows. For compressible fluids, each type of tracer is shown to monitor a fundamentally different fluid velocity, with (i) a dye (or any other such molecular-tagging scheme) measuring the fluid's mass velocity v appearing in the continuity equation and (ii) a small, physicochemically and thermally inert, macroscopic (i.e., non-Brownian), solid particle measuring the fluid's volume velocity vv. The term “compressibility” as used here includes not only pressure effects on density, but also temperature effects thereon. (For example, owing to a liquid's generally nonzero isobaric coefficient of thermal expansion, nonisothermal liquid flows are to be regarded as compressible despite the general perception of liquids as being incompressible.) Recognition of the fact that two independent fluid velocities, mass- and volume-based, are formally required to model continuum fluid behavior impacts on the foundations of contemporary (monovelocity) fluid mechanics. Included therein are the Navier-Stokes-Fourier equations, which are now seen to apply only to incompressible fluids (a fact well-known, empirically, to experimental gas kineticists). The findings of a difference in tracer velocities heralds the introduction into fluid mechanics of a general bipartite theory of fluid mechanics, bivelocity hydrodynamics [Brenner, Int. J. Eng. Sci.10.1016/j.ijengsci.2012.01.006 54, 67 (2012)], differing from conventional hydrodynamics in situations entailing compressible flows and reducing to conventional hydrodynamics when the flow is incompressible, while being applicable to both liquids and

  13. Signature spectrale des grains interstellaires.

    NASA Astrophysics Data System (ADS)

    Léger, A.

    Notre connaissance de la nature des grains interstellaires reposait sur un nombre très restreint de signatures spectrales dans la courbe d'extinction du milieu interstellaire. Une information considérable est contenue dans les 40 bandes interstellaires diffuses dans le visible, mais reste inexploitée. L'interprétation récente des cinq bandes IR en émission, en terme de molécules d'hydrocarbures aromatiques polycycliques, est développée. Elle permet l'utilisation d'une information spectroscopique comparable, à elle seule, à ce sur quoi était basée jusqu'alors notre connaissance de la matière interstellaire condensée. Différentes implications de cette mise en évidence sont proposées.

  14. Fluid transport container

    DOEpatents

    DeRoos, Bradley G.; Downing, Jr., John P.; Neal, Michael P.

    1995-01-01

    An improved fluid container for the transport, collection, and dispensing of a sample fluid that maintains the fluid integrity relative to the conditions of the location at which it is taken. More specifically, the invention is a fluid sample transport container that utilizes a fitment for both penetrating and sealing a storage container under controlled conditions. Additionally, the invention allows for the periodic withdrawal of portions of the sample fluid without contamination or intermixing from the environment surrounding the sample container.

  15. Fluid transport container

    DOEpatents

    DeRoos, B.G.; Downing, J.P. Jr.; Neal, M.P.

    1995-11-14

    An improved fluid container for the transport, collection, and dispensing of a sample fluid that maintains the fluid integrity relative to the conditions of the location at which it is taken. More specifically, the invention is a fluid sample transport container that utilizes a fitting for both penetrating and sealing a storage container under controlled conditions. Additionally, the invention allows for the periodic withdrawal of portions of the sample fluid without contamination or intermixing from the environment surrounding the sample container. 13 figs.

  16. Transport quantique dans des nanostructures

    NASA Astrophysics Data System (ADS)

    Naud, C.

    2002-09-01

    structure des oscillations de conductance en fonction du flux du champ magnétique de période h/e dont l'amplitude est beaucoup plus importante que celle mesurée sur un réseau carré de même dimension. Cette différence constitue une signature d'un effet de localisation induit par le champ magnétique sur la topologie mathcal{T}3. Pour des valeurs spécifiques du champ magnétique, du fait des interférences destructives Aharonov-Bohm, la propagation des fonctions d'ondes est limitée à un ensemble fini de cellule du réseau appelé cage. De la dépendance en température des oscillations de période h/e mesurées sur le réseau mathcal{T}3 nous avons tiré une longueur caractéristique qui peut être rattachée au périmètre des cages. Un phénomène inattendu fut l'observation, pour des champs magnétiques plus importants, d'un doublement de fréquence des oscillations. Ces oscillations de période h/2e pouvant avoir une amplitude supérieure aux oscillations de période h/e, une interprétation en terme d'harmonique n'est pas possible. Enfin, l'influence de la largeur électrique des fils constituant le réseau et donc celle du nombre de canaux par brin a été étudiée en réalisant des grilles électrostatique. Les variations de l'amplitude des signaux en h/e et h/2e en fonction de la tension de grille ont été mesurés.

  17. Postoperative fluid management

    PubMed Central

    Kayilioglu, Selami Ilgaz; Dinc, Tolga; Sozen, Isa; Bostanoglu, Akin; Cete, Mukerrem; Coskun, Faruk

    2015-01-01

    Postoperative care units are run by an anesthesiologist or a surgeon, or a team formed of both. Management of postoperative fluid therapy should be done considering both patients’ status and intraoperative events. Types of the fluids, amount of the fluid given and timing of the administration are the main topics that determine the fluid management strategy. The main goal of fluid resuscitation is to provide adequate tissue perfusion without harming the patient. The endothelial glycocalyx dysfunction and fluid shift to extracellular compartment should be considered wisely. Fluid management must be done based on patient’s body fluid status. Patients who are responsive to fluids can benefit from fluid resuscitation, whereas patients who are not fluid responsive are more likely to suffer complications of over-hydration. Therefore, common use of central venous pressure measurement, which is proved to be inefficient to predict fluid responsiveness, should be avoided. Goal directed strategy is the most rational approach to assess the patient and maintain optimum fluid balance. However, accessible and applicable monitoring tools for determining patient’s actual fluid need should be further studied and universalized. The debate around colloids and crystalloids should also be considered with goal directed therapies. Advantages and disadvantages of each solution must be evaluated with the patient’s specific condition. PMID:26261771

  18. Fluid sampling pump

    SciTech Connect

    Allen, P.V.; Nimberger, M.; Ward, R.L.

    1991-12-24

    This patent describes a fluid sampling pump for withdrawing pressurized sample fluid from a flow line and for pumping a preselected quantity of sample fluid with each pump driving stroke from the pump to a sample vessel, the sampling pump including a pump body defining a pump bore therein having a central axis, a piston slideably moveable within the pump bore and having a fluid inlet end and an opposing operator end, a fluid sample inlet port open to sample fluid in the flow line, a fluid sample outlet port for transmitting fluid from the pump bore to the sample vessel, and a line pressure port in fluid pressure sample fluid in the flow line, an inlet valve for selectively controlling sample fluid flow from the flow line through the fluid sample inlet port, an operator unit for periodically reciprocating the piston within the pump bore, and a controller for regulating the stroke of the piston within the pump bore, and thereby the quantity of fluid pumped with each pump driving stroke. It comprises a balanced check valve seat; a balanced check valve seal; a compression member; and a central plunger.

  19. Environmentally safe fluid extractor

    DOEpatents

    Sungaila, Zenon F.

    1993-01-01

    An environmentally safe fluid extraction device for use in mobile laboratory and industrial settings comprising a pump, compressor, valving system, waste recovery tank, fluid tank, and a exhaust filtering system.

  20. Pleural fluid analysis

    MedlinePlus

    ... of fluid that has collected in the pleural space. This is the space between the lining of the outside of the ... the chest. When fluid collects in the pleural space, the condition is called pleural effusion .

  1. Pleural fluid smear

    MedlinePlus

    ... the fluid that has collected in the pleural space. This is the space between the lining of the outside of the ... the chest. When fluid collects in the pleural space, the condition is called pleural effusion .

  2. Peritoneal fluid analysis

    MedlinePlus

    ... at fluid that has built up in the space in the abdomen around the internal organs. This area is called the peritoneal space. ... sample of fluid is removed from the peritoneal space using a needle and syringe. Your health care ...

  3. Fluid sampling tool

    DOEpatents

    Johnston, Roger G.; Garcia, Anthony R. E.; Martinez, Ronald K.

    2001-09-25

    The invention includes a rotatable tool for collecting fluid through the wall of a container. The tool includes a fluid collection section with a cylindrical shank having an end portion for drilling a hole in the container wall when the tool is rotated, and a threaded portion for tapping the hole in the container wall. A passageway in the shank in communication with at least one radial inlet hole in the drilling end and an opening at the end of the shank is adapted to receive fluid from the container. The tool also includes a cylindrical chamber affixed to the end of the shank opposite to the drilling portion thereof for receiving and storing fluid passing through the passageway. The tool also includes a flexible, deformable gasket that provides a fluid-tight chamber to confine kerf generated during the drilling and tapping of the hole. The invention also includes a fluid extractor section for extracting fluid samples from the fluid collecting section.

  4. Electric fluid pump

    DOEpatents

    Van Dam, Jeremy Daniel; Turnquist, Norman Arnold; Raminosoa, Tsarafidy; Shah, Manoj Ramprasad; Shen, Xiaochun

    2015-09-29

    An electric machine is presented. The electric machine includes a hollow rotor; and a stator disposed within the hollow rotor, the stator defining a flow channel. The hollow rotor includes a first end portion defining a fluid inlet, a second end portion defining a fluid outlet; the fluid inlet, the fluid outlet, and the flow channel of the stator being configured to allow passage of a fluid from the fluid inlet to the fluid outlet via the flow channel; and wherein the hollow rotor is characterized by a largest cross-sectional area of hollow rotor, and wherein the flow channel is characterized by a smallest cross-sectional area of the flow channel, wherein the smallest cross-sectional area of the flow channel is at least about 25% of the largest cross-sectional area of the hollow rotor. An electric fluid pump and a power generation system are also presented.

  5. Pericardial fluid culture

    MedlinePlus

    ... medlineplus.gov/ency/article/003720.htm Pericardial fluid culture To use the sharing features on this page, please enable JavaScript. Pericardial fluid culture is a test performed on a sample of ...

  6. Environmentally safe fluid extractor

    DOEpatents

    Sungaila, Zenon F.

    1993-07-06

    An environmentally safe fluid extraction device for use in mobile laboratory and industrial settings comprising a pump, compressor, valving system, waste recovery tank, fluid tank, and a exhaust filtering system.

  7. Peritoneal fluid culture

    MedlinePlus

    Culture - peritoneal fluid ... sent to the laboratory for Gram stain and culture. The sample is checked to see if bacteria ... based on more than just the peritoneal fluid culture (which may be negative even if you have ...

  8. Fluid force transducer

    DOEpatents

    Jendrzejczyk, Joseph A.

    1982-01-01

    An electrical fluid force transducer for measuring the magnitude and direction of fluid forces caused by lateral fluid flow, includes a movable sleeve which is deflectable in response to the movement of fluid, and a rod fixed to the sleeve to translate forces applied to the sleeve to strain gauges attached to the rod, the strain gauges being connected in a bridge circuit arrangement enabling generation of a signal output indicative of the magnitude and direction of the force applied to the sleeve.

  9. Fluid Movement and Creativity

    ERIC Educational Resources Information Center

    Slepian, Michael L.; Ambady, Nalini

    2012-01-01

    Cognitive scientists describe creativity as fluid thought. Drawing from findings on gesture and embodied cognition, we hypothesized that the physical experience of fluidity, relative to nonfluidity, would lead to more fluid, creative thought. Across 3 experiments, fluid arm movement led to enhanced creativity in 3 domains: creative generation,…

  10. Goal directed fluid therapy.

    PubMed

    Marik, Paul E; Desai, Himanshu

    2012-01-01

    The cornerstone of treating patients with shock remains as it has for decades, intravenous fluids. Surprisingly, dosing intravenous fluid during resuscitation of shock remains largely empirical. Recent data suggests that early aggressive resuscitation of critically ill patients may limit and/or reverse tissue hypoxia, progression to organ failure and improve outcome. However, overzealous fluid resuscitation has been associated with increased complications, increased length of intensive care unit (ICU) and hospital stay and increased mortality. This review focuses on methods to assess fluid responsiveness and the application of these methods for goal directed fluid therapy in critically ill and peri-operative patients.

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

    NASA Astrophysics Data System (ADS)

    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.

  12. Pronostic visuel et évolution réfractive après chirurgie de la cataracte congénitale avec implantation primaire: étude d'une série de 108 cas

    PubMed Central

    Hafidi, Zouheir; Ibrahimy, Wafaa; Ahid, Samir; Handor, Hanan; Ouafae Cherkaoui, Lalla; Bencherif, Zahid; Laghmari, Mina; Ouazzanni, Btissam; Boutimzine, Noureddine; Daoudi, Rajae

    2013-01-01

    La cataracte congénitale constitue la cause la plus fréquente de cécité évitable chez les enfants. Le but de cette étude est d’évaluer le pronostic réfractif et fonctionnel, des enfants opérés de cataracte congénitale avec implantation. Il s'agit d'une étude rétrospective de 108 enfants, dont 85 cataractes bilatérales, 23 unilatérales opérés entre 2007 et 2011. La réfraction a été mesurée à 1 mois, 3 mois, 6 mois, 1 an, 2 ans, 3 ans et/ou 4 ans en post-opératoire. La meilleure acuité visuelle corrigée, ainsi que l'incidence des complications post-opératoires ont été analysé. L’âge moyen de la chirurgie était de 25 mois avec une durée moyenne de suivi de 3,17 ans. Les complications retrouvées étaient l'inflammation, la prolifération secondaire, et le glaucome. L'acuité visuelle (AV) moyenne corrigée finale était de 5,75/10e pour les formes bilatérales, et de 4,16/10e pour les unilatérales (p = 0,001). Les facteurs de mauvais pronostic retrouvés étaient l’âge tardif de la chirurgie, la densité de la cataracte et la survenue de complications (p = 0,001). L'incidence des complications post-opératoires était significativement plus élevé chez les enfants opérés à un jeune âge (p = 0,001). Les facteurs de mauvais pronostic visuel chez les enfants opérés pour cataracte congénitale avec implantation, sont représentés par le caractère unilatéral de la cataracte, l’âge tardif de la chirurgie, la densité de la cataracte et la survenue de complications post opératoires. PMID:24672622

  13. Spinning fluids reactor

    DOEpatents

    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.

  14. Perioperative Fluid Restriction

    PubMed Central

    Bleier, Joshua I.S.; Aarons, Cary B.

    2013-01-01

    Perioperative fluid management of the colorectal surgical patient has evolved significantly over the last five decades. Older notions espousing aggressive hydration have been shown to be associated with increased complications. Newer data regarding fluid restriction has shown an association with improved outcomes. Management of perioperative fluid administration can be considered in three primary phases: In the preoperative phase, data suggests that avoidance of preoperative bowel preparation and avoidance of undue preoperative dehydration can improve outcomes. Although the type of intraoperative fluid given does not have a significant effect on outcome, data do suggest that a restrictive fluid regimen results in improved outcomes. Finally, in the postoperative phase of fluid management, a fluid-restrictive regimen, coupled with early enteral feeding also seems to result in improved outcomes. PMID:24436675

  15. Fluid cooled electrical assembly

    DOEpatents

    Rinehart, Lawrence E.; Romero, Guillermo L.

    2007-02-06

    A heat producing, fluid cooled assembly that includes a housing made of liquid-impermeable material, which defines a fluid inlet and a fluid outlet and an opening. Also included is an electrical package having a set of semiconductor electrical devices supported on a substrate and the second major surface is a heat sink adapted to express heat generated from the electrical apparatus and wherein the second major surface defines a rim that is fit to the opening. Further, the housing is constructed so that as fluid travels from the fluid inlet to the fluid outlet it is constrained to flow past the opening thereby placing the fluid in contact with the heat sink.

  16. Ostéosynthèse des fractures des métacarpiens et des phalanges de la main par mini plaque: à propos de 12 cas

    PubMed Central

    Moncef, Erraji; Abdelhafid, Derfoufi; Abdessamad, Kharraji; Omar, Agoumi; Najib, Abdeljaouad; Abdelkrim, Daoudi; Hicham, Yacoubi

    2016-01-01

    Le traitement des fractures instables des métacarpes et des phalanges reste un objet de controverse. Peu de séries ont été rapportées dans la littérature, rendant leur analyse difficile. Nous rapportons une étude rétrospective comportant 12 patients, opérés par cette technique, ayant eu des fractures déplacées des métacarpes ou des phalanges, sur une période de deux ans. Les résultats globaux ont été bons dans 75% des cas, moyenne dans 16,5% des cas et mauvais dans 8,5% des cas. La stabilité du montage par mini plaques des fractures instables des métacarpiens et des phalanges ont permis une mobilisation précoce des articulations de la main, évitant ainsi la raideur. PMID:27800079

  17. Fluid sampling pump

    SciTech Connect

    Allen, P.V.; Nimberger, S.M.; Ward, R.L.

    1992-03-03

    This patent describes a pump for pumping a preselected quantity of fluid with each pump driving stroke from a fluid inlet port to a fluid outlet port, an inlet valve for selectively controlling fluid flow through the fluid inlet port, a pump body defining a pump bore therein, a piston slidably movable within the pump bore and having a fluid inlet end and an opposing operator end, an operator unit for reciprocating the piston within the pump bore, and a manifold interconnect with the pump body. It comprises a flow path therein extending from a manifold inlet port to a manifold outlet port, flow path being in communication with the fluid outlet port in the pump body, a purge passageway extending from the flow path to the outlet passageway, a purge valve for regulating fluid flow through the purge passageway, and a filter positioned within the manifold and extending across a portion of the flow path, the filter defining a filtered zone within the flow path adjoining the inlet port in the pump body, and an unfiltered zone within the flow path extending from the manifold inlet to the manifold outlet, such that filtered fluid enters the pump bore while unfiltered fluid bypasses the filter and passes out the manifold outlet port.

  18. Peste des Petits Ruminants Virus.

    PubMed

    Baron, M D; Diallo, A; Lancelot, R; Libeau, G

    2016-01-01

    Peste des petits ruminants virus (PPRV) causes a severe contagious disease of sheep and goats and has spread extensively through the developing world. Because of its disproportionately large impact on the livelihoods of low-income livestock keepers, and the availability of effective vaccines and good diagnostics, the virus is being targeted for global control and eventual eradication. In this review we examine the origin of the virus and its current distribution, and the factors that have led international organizations to conclude that it is eradicable. We also review recent progress in the molecular and cellular biology of the virus and consider areas where further research is required to support the efforts being made by national, regional, and international bodies to tackle this growing threat.

  19. Microwave fluid flow meter

    DOEpatents

    Billeter, Thomas R.; Philipp, Lee D.; Schemmel, Richard R.

    1976-01-01

    A microwave fluid flow meter is described utilizing two spaced microwave sensors positioned along a fluid flow path. Each sensor includes a microwave cavity having a frequency of resonance dependent upon the static pressure of the fluid at the sensor locations. The resonant response of each cavity with respect to a variation in pressure of the monitored fluid is represented by a corresponding electrical output which can be calibrated into a direct pressure reading. The pressure drop between sensor locations is then correlated as a measure of fluid velocity. In the preferred embodiment the individual sensor cavities are strategically positioned outside the path of fluid flow and are designed to resonate in two distinct frequency modes yielding a measure of temperature as well as pressure. The temperature response can then be used in correcting for pressure responses of the microwave cavity encountered due to temperature fluctuations.

  20. Fiber optic fluid detector

    DOEpatents

    Angel, S. Michael

    1989-01-01

    Particular gases or liquids are detected with a fiber optic element (11, 11a to 11j) having a cladding or coating of a material (23, 23a to 23j) which absorbs the fluid or fluids and which exhibits a change of an optical property, such as index of refraction, light transmissiveness or fluoresence emission, for example, in response to absorption of the fluid. The fluid is sensed by directing light into the fiber optic element and detecting changes in the light, such as exit angle changes for example, that result from the changed optical property of the coating material. The fluid detector (24, 24a to 24j) may be used for such purposes as sensing toxic or explosive gases in the atmosphere, measuring ground water contamination or monitoring fluid flows in industrial processes, among other uses.

  1. Fiber optic fluid detector

    DOEpatents

    Angel, S.M.

    1987-02-27

    Particular gases or liquids are detected with a fiber optic element having a cladding or coating of a material which absorbs the fluid or fluids and which exhibits a change of an optical property, such as index of refraction, light transmissiveness or fluoresence emission, for example, in response to absorption of the fluid. The fluid is sensed by directing light into the fiber optic element and detecting changes in the light, such as exit angle changes for example, that result from the changed optical property of the coating material. The fluid detector may be used for such purposes as sensing toxic or explosive gases in the atmosphere, measuring ground water contamination or monitoring fluid flows in industrial processes, among other uses. 10 figs.

  2. Applications of supercritical fluids.

    PubMed

    Brunner, Gerd

    2010-01-01

    This review discusses supercritical fluids in industrial and near-to-industry applications. Supercritical fluids are flexible tools for processing materials. Supercritical fluids have been applied to mass-transfer processes, phase-transition processes, reactive systems, materials-related processes, and nanostructured materials. Some applications are already at industrial capacity, whereas others remain under development. In addition to extraction, application areas include impregnation and cleaning, multistage countercurrent separation, particle formation, coating, and reactive systems such as hydrogenation, biomass gasification, and supercritical water oxidation. Polymers are modified with supercritical fluids, and colloids and emulsions as well as nanostructured materials exhibit interesting phenomena when in contact with supercritical fluids that can be industrially exploited. For these applications to succeed, the properties of supercritical fluids in combination with the materials processed must be clearly determined and fundamental knowledge of the complex behavior must be made readily available.

  3. Disposal of drilling fluids

    SciTech Connect

    Bryson, W.R.

    1983-06-01

    Prior to 1974 the disposal of drilling fluids was not considered to be much of an environmental problem. In the past, disposal of drilling fluids was accomplished in various ways such as spreading on oil field lease roads to stabilize the road surface and control dust, spreading in the base of depressions of sandy land areas to increase water retention, and leaving the fluid in the reserve pit to be covered on closure of the pit. In recent years, some states have become concerned over the indescriminate dumping of drilling fluids into pits or unauthorized locations and have developed specific regulations to alleviate the perceived deterioration of environmental and groundwater quality from uncontrolled disposal practices. The disposal of drilling fluids in Kansas is discussed along with a newer method or treatment in drilling fluid disposal.

  4. Greening America's Capitals - Des Moines, IA

    EPA Pesticide Factsheets

    Report from Greening America's Capitals project in Des Moines, IA, to help the city enhance the 6th Avenue Corridor with pedestrian and bike improvements and green infrastructure to manage stormwater.

  5. Persistent interface fluid syndrome.

    PubMed

    Hoffman, Richard S; Fine, I Howard; Packer, Mark

    2008-08-01

    We present an unusual case of persistent interface fluid that would not resolve despite normal intraocular pressure and corneal endothelial replacement with Descemet-stripping endothelial keratoplasty. Dissection, elevation, and repositioning of the laser in situ keratomileusis flap were required to resolve the interface fluid. Circumferential corneal graft-host margin scar formation acting as a mechanical strut may have been the cause of the intractable interface fluid.

  6. Solar heat transport fluid

    NASA Technical Reports Server (NTRS)

    1978-01-01

    The progress made on the development and delivery of noncorrosive fluid subsystems is reported. These subsystems are to be compatible with closed-loop solar heating or combined heating and hot water systems. They are also to be compatible with both metallic and non-metallic plumbing systems. At least 100 gallons of each type of fluid recommended by the contractor will be delivered under the contract. The performance testing of a number of fluids is described.

  7. Fluid pumping system

    SciTech Connect

    Heath, R.T.; Gerlach, C.R.

    1986-05-13

    A fluid pumping system is described for use with a natural gas dehydrating system or the like having an absorber apparatus for removing water from wet natural gas to produce dry natural gas by use of a dessicant agent such as glycol, and a glycol treater apparatus for producing a source of dry glycol from wet glycol received from the absorber apparatus. The system consists of: a fluid pump means operatively connected between dry glycol source and absorber apparatus for pumping dry glycol from the dry glycol source to the absorber apparatus; a fluid operable piston motor means operatively associated with the pump means for driving the pump means and having fluid inlet passage means for receiving wet glycol from the absorber and fluid outlet passage means for delivering wet glycol to the glycol reboiler means wherein energy derived from the flow of fluid passing through the fluid inlet passage means provides the entire motivating force for the motor means and the pump means; the fluid pump means comprising a first pair of equal diameter chamber portion of a double acting piston means having a piston rod with two oppositely positioned piston heads at terminal ends thereof received within two oppositely positioned cylinders mounted on a fixed central body which slidably supports the piston rod; the fluid operable motor means comprising a second pair of equal diameter chamber portions of the double acting piston means; the effective areas of outwardly directed faces of the piston heads being substantially greater than the effective areas of inwardly directed faces of the piston heads; and a wet glycol passage shifting means associated with the fluid motor means for automatically changing the porting of the fluid motor means at the end of a piston stroke for producing reciprocal piston motion in the fluid motor means including toggle means actuated by the piston rod.

  8. Metalworking and machining fluids

    DOEpatents

    Erdemir, Ali; Sykora, Frank; Dorbeck, Mark

    2010-10-12

    Improved boron-based metal working and machining fluids. Boric acid and boron-based additives that, when mixed with certain carrier fluids, such as water, cellulose and/or cellulose derivatives, polyhydric alcohol, polyalkylene glycol, polyvinyl alcohol, starch, dextrin, in solid and/or solvated forms result in improved metalworking and machining of metallic work pieces. Fluids manufactured with boric acid or boron-based additives effectively reduce friction, prevent galling and severe wear problems on cutting and forming tools.

  9. Perioperative Fluid Therapy.

    PubMed

    Fantoni, Denise; Shih, Andre C

    2017-03-01

    Anesthesia can lead to pathophysiologic changes that dramatically alter the fluid balance of the body compartments and the intravascular space. Fluid administration can be monitored and evaluated using static and dynamic indexes. Guidelines for fluid rates during anesthesia begin with 3 mL/kg/h in cats and 5 mL/kg/h in dogs. If at all possible, patients should be stabilized and electrolyte disturbances should be corrected before general anesthesia.

  10. Thermogelling magnetorheological fluids

    NASA Astrophysics Data System (ADS)

    Shahrivar, Keshvad; de Vicente, Juan

    2014-02-01

    A novel approach is proposed for the formulation of kinetically stable magnetorheological (MR) fluids exhibiting an MR effect. Thermoresponsive carrier fluids are used which develop a sol-gel transition on increasing the temperature. Turbidity measurements, multiwave rheology and steady shear flow tests are carried out on model conventional MR fluids prepared by dispersion of carbonyl iron microparticles in triblock copolymer solutions of type PEOx-PPOy-PEOx with x = 100 and y = 65. Experiments demonstrate that the MR fluids remain stable against sedimentation in the gel phase and exhibit a very large (relative) MR effect (up to 1000%) in the sol phase.

  11. The Fluids RAP

    NASA Astrophysics Data System (ADS)

    Nedyalkov, Ivaylo

    2016-11-01

    After fifteen years of experience in rap, and ten in fluid mechanics, "I am coming here with high-Reynolds-number stamina; I can beat these rap folks whose flows are... laminar." The rap relates fluid flows to rap flows. The fluid concepts presented in the song have varying complexity and the listeners/viewers will be encouraged to read the explanations on a site dedicated to the rap. The music video will provide an opportunity to share high-quality fluid visualizations with a general audience. This talk will present the rap lyrics, the vision for the video, and the strategy for outreach. Suggestions and comments will be welcomed.

  12. Peritoneal Fluid Analysis

    MedlinePlus

    ... tests for viruses, mycobacteria ( AFB testing in identifying tuberculosis ), and parasites Adenosine deaminase – rarely ordered for detecting tuberculosis in peritoneal fluid ^ Back to top When is ...

  13. Electrorheological fluids and methods

    DOEpatents

    Green, Peter F.; McIntyre, Ernest C.

    2015-06-02

    Electrorheological fluids and methods include changes in liquid-like materials that can flow like milk and subsequently form solid-like structures under applied electric fields; e.g., about 1 kV/mm. Such fluids can be used in various ways as smart suspensions, including uses in automotive, defense, and civil engineering applications. Electrorheological fluids and methods include one or more polar molecule substituted polyhedral silsesquioxanes (e.g., sulfonated polyhedral silsesquioxanes) and one or more oils (e.g., silicone oil), where the fluid can be subjected to an electric field.

  14. Spiral fluid separator

    NASA Technical Reports Server (NTRS)

    Robertson, Glen A. (Inventor)

    1993-01-01

    A fluid separator for separating particulate matter such as contaminates is provided which includes a series of spiral tubes of progressively decreasing cross sectional area connected in series. Each tube has an outlet on the outer curvature of the spiral. As fluid spirals down a tube, centrifugal force acts to force the heavier particulate matter to the outer wall of the tube, where it exits through the outlet. The remaining, and now cleaner, fluid reaches the next tube, which is smaller in cross sectional area, where the process is repeated. The fluid which comes out the final tube is diminished of particulate matter.

  15. Essais de capillarité et d'évaporation sous tomodensitométrie RX imagerie de la répartition de l'eau. Conséquences sur les flux et la localisation des zones de précipitation des sels

    NASA Astrophysics Data System (ADS)

    Géraud, Y.; Tournier, B.; Surma, F.; Mazerolle, F.

    2002-07-01

    La tomodensitométrie Rx est utilisée pour suivre la saturation et le séchage des pierres utilisées dans la construction de certains monuments. Les mesures d'atténuation des rayons X sont interprétées pour déterminer la répartition des phases minérales qui composent le matériau ainsi que la répartition de la porosité. Les essais de saturation ou de séchage effectués sous tomodensitométrie RX permettent de suivre les variations de saturation du réseau poreux au cours des essais. Les interfaces entre zones saturées en fluides et zones sèches localisent de possibles zones de précipitation de sels, processus important dans le dégradation de pierres d'œuvre.

  16. Space Station fluid management logistics

    NASA Technical Reports Server (NTRS)

    Dominick, Sam M.

    1990-01-01

    Viewgraphs and discussion on space station fluid management logistics are presented. Topics covered include: fluid management logistics - issues for Space Station Freedom evolution; current fluid logistics approach; evolution of Space Station Freedom fluid resupply; launch vehicle evolution; ELV logistics system approach; logistics carrier configuration; expendable fluid/propellant carrier description; fluid carrier design concept; logistics carrier orbital operations; carrier operations at space station; summary/status of orbital fluid transfer techniques; Soviet progress tanker system; and Soviet propellant resupply system observations.

  17. Calendar of Selected Aeronautical and Space Meetings January 1988 (Calendrier des Manifestations Aeronautiques et Spatiales (Selection) Janvier 1988).

    DTIC Science & Technology

    1987-12-01

    aerospatiales2 02 - Electronique, Optique et Metrologie 03 - Mccaniquec du Vol 28 04 - Dynamnique des Fluides et Acoustique 30 05 - Navigation, Guidagce t...Ferromagnetism 07-42, 07-43, 07-65. 07-71 Fibre Optics 02-03, 02-12. 02-13. 02-22. (2-39. 02-44. 02-53. 02-54. 02-56). 02-78, 02-83. 02-84. 12-18 Fibre

  18. Fluids and Combustion Facility: Fluids Integrated Rack

    NASA Technical Reports Server (NTRS)

    Corban, Robert R.; Winsa, Edward A.

    1998-01-01

    The Fluids Integrated Rack (FIR) is a modular, multi-user facility to accommodate a wide variety of microgravity fluid physics science experiments on-board the US Laboratory Module of the International Space Station (ISS). The FIR is one of three racks comprising the Fluids and Combustion Facility (FCF). The FCF is being designed to increase the amount and quality of scientific data and decrease the development cost of an individual experiment relative to the era of Space Shuttle experiments. The unique, long-term, microgravity environment and long operational times on the ISS will offer experimenters the opportunity to modify experiment parameters based on their findings similar to what can be accomplished in ground laboratories. The FIR concept has evolved over time to provide a flexible, 'optics bench' approach to meet the wide variety of anticipated research needs. The FIR's system architecture presented is designed to meet the needs of the fluid physics community while operating within the constraints of the available ISS resources.

  19. Fluid Bubble Eliminator

    NASA Technical Reports Server (NTRS)

    Gonda, Steve R. (Inventor); Tsao, Yow-Min (Inventor); Lee, Wenshan (Inventor)

    2005-01-01

    A gas-liquid separator uses a helical passageway to impart a spiral motion to a fluid passing therethrough. The centrifugal fore generated by the spiraling motion urges the liquid component of the fluid radially outward which forces the gas component radially inward. The gas component is then filtered through a gas-permeable, liquid-impervious membrane and discharged through a central passageway.

  20. Fluid bubble eliminator

    NASA Technical Reports Server (NTRS)

    Gonda, Steve R. (Inventor); Tsao, Yow-Min D. (Inventor); Lee, Wenshan (Inventor)

    2005-01-01

    A gas-liquid separator uses a helical passageway to impart a spiral motion to a fluid passing therethrough. The centrifugal fore generated by the spiraling motion urges the liquid component of the fluid radially outward which forces the gas component radially inward. The gas component is then filtered through a gas-permeable, liquid-impervious membrane and discharged through a central passageway.

  1. Fluid delivery control system

    SciTech Connect

    Hoff, Brian D.; Johnson, Kris William; Algrain, Marcelo C.; Akasam, Sivaprasad

    2006-06-06

    A method of controlling the delivery of fluid to an engine includes receiving a fuel flow rate signal. An electric pump is arranged to deliver fluid to the engine. The speed of the electric pump is controlled based on the fuel flow rate signal.

  2. Time Independent Fluids

    ERIC Educational Resources Information Center

    Collyer, A. A.

    1973-01-01

    Discusses theories underlying Newtonian and non-Newtonian fluids by explaining flow curves exhibited by plastic, shear-thining, and shear-thickening fluids and Bingham plastic materials. Indicates that the exact mechanism governing shear-thickening behaviors is a problem of further study. (CC)

  3. Fluid Power Technician

    ERIC Educational Resources Information Center

    Moore, Pam

    2008-01-01

    Fluid power technicians, sometimes called hydraulic and pneumatic technicians, work with equipment that utilizes the pressure of a liquid or gas in a closed container to transmit, multiply, or control power. Working under the supervision of an engineer or engineering staff, they assemble, install, maintain, and test fluid power equipment.…

  4. Fluid-loss control

    SciTech Connect

    Crowe, C.W.; Trittipo, B.L. ); Hutchinson, B.H. )

    1989-08-01

    Acid fluid loss is extremely difficult to control and is generally considered to be the major factor limiting the effectiveness of acid fracturing treatments. Chemical erosion of fracture faces and the development of wormholes are largely responsible for the reduced efficiency of acid fracturing fluids. The creation of acid wormholes increases the effective area from which leakoff occurs, thus reducing the acid hydraulic efficiency. Once wormholes form, most acid fluid loss originates from these wormholes rather than penetrating uniformly into the fracture face. Methods of acid fluid-loss control are discussed and evaluated with an improved fluid-loss test procedure. This procedure uses limestone cores of sufficient length to contain wormhole growth. Studies demonstrate that if wormhole growth can be controlled, acid fluid loss approaches that of nonreactive fluids. An improved acid fracturing fluid having unique rheological characteristics is described. This acid has a low initial viscosity but temporarily becomes extremely viscous during leakoff. This high leakoff viscosity blocks wormhole development and prevents acid entry into natural fractures. After the treatment, spent-acid viscosity declines rapidly to ensure easier cleanup.

  5. FLUID SELECTING APPARATUS

    DOEpatents

    Stinson, W.J.

    1958-09-16

    A valve designed to selectively sample fluids from a number of sources is described. The valve comprises a rotatable operating lever connected through a bellows seal to a rotatable assembly containing a needle valve, bearings, and a rotational lock. The needle valve is connected through a flexible tube to the sample fluid outlet. By rotating the lever the needle valve is placed over . one of several fluid sources and locked in position so that the fluid is traasferred through the flexible tubing and outlet to a remote sampling system. The fluids from the nonselected sources are exhausted to a waste line. This valve constitutes a simple, dependable means of selecting a sample from one of several scurces.

  6. Fluid structure interaction

    NASA Astrophysics Data System (ADS)

    Komatsu, K.

    A few nonflow field problems are considered, taking into account mainly fluid-shell dynamic interaction and fluid-solid impact. Fluid-shell systems are used as models for sloshing and POGO (structure-propulsion coupling oscillation) in liquid rockets, floating lids of oil tanks, large tanks containing fluid, nuclear containment vessels, and head injury studies in biomechanics. The study of structure-water impact finds applications in the problems associated with water landings of reentry vehicles, water entry of torpedoes, and slamming of ships in heavy seas. At least three different methods can be used in handling wet structures. Attention is given to the method which treats fluid by boundary elements and structure by finite elements.

  7. Fluid blade disablement tool

    DOEpatents

    Jakaboski, Juan-Carlos [Albuquerque, NM; Hughs, Chance G [Albuquerque, NM; Todd, Steven N [Rio Rancho, NM

    2012-01-10

    A fluid blade disablement (FBD) tool that forms both a focused fluid projectile that resembles a blade, which can provide precision penetration of a barrier wall, and a broad fluid projectile that functions substantially like a hammer, which can produce general disruption of structures behind the barrier wall. Embodiments of the FBD tool comprise a container capable of holding fluid, an explosive assembly which is positioned within the container and which comprises an explosive holder and explosive, and a means for detonating. The container has a concavity on the side adjacent to the exposed surface of the explosive. The position of the concavity relative to the explosive and its construction of materials with thicknesses that facilitate inversion and/or rupture of the concavity wall enable the formation of a sharp and coherent blade of fluid advancing ahead of the detonation gases.

  8. Constraining the dark fluid

    SciTech Connect

    Kunz, Martin; Liddle, Andrew R.; Parkinson, David; Gao Changjun

    2009-10-15

    Cosmological observations are normally fit under the assumption that the dark sector can be decomposed into dark matter and dark energy components. However, as long as the probes remain purely gravitational, there is no unique decomposition and observations can only constrain a single dark fluid; this is known as the dark degeneracy. We use observations to directly constrain this dark fluid in a model-independent way, demonstrating, in particular, that the data cannot be fit by a dark fluid with a single constant equation of state. Parametrizing the dark fluid equation of state by a variety of polynomials in the scale factor a, we use current kinematical data to constrain the parameters. While the simplest interpretation of the dark fluid remains that it is comprised of separate dark matter and cosmological constant contributions, our results cover other model types including unified dark energy/matter scenarios.

  9. Microgravity Fluid Management Symposium

    NASA Technical Reports Server (NTRS)

    1987-01-01

    The NASA Microgravity Fluid Management Symposium, held at the NASA Lewis Research Center, September 9 to 10, 1986, focused on future research in the microgravity fluid management field. The symposium allowed researchers and managers to review space applications that require fluid management technology, to present the current status of technology development, and to identify the technology developments required for future missions. The 19 papers covered three major categories: (1) fluid storage, acquisition, and transfer; (2) fluid management applications, i.e., space power and thermal management systems, and environmental control and life support systems; (3) project activities and insights including two descriptions of previous flight experiments and a summary of typical activities required during development of a shuttle flight experiment.

  10. Simulation des phenomenes aeroelastiques des pales d'eoliennes

    NASA Astrophysics Data System (ADS)

    Ramdenee, Drishtysingh

    This project concentrates on the study of aeroelastic effects affecting wind turbines blades. The first objective of this project was to conduct an analytical study of the intrinsic aeroelastic effects, choose the most appropriate software for aeroelastic effects simulation, calibrate the tool (the mesh size, the turbulence models, the transition models, etc.) and compare with existing experimental results to validate the model. As second objective, the project simplified the very precise CFD (Computational Fluid Dynamics) model based on coupling finite volume and finite element tools into a lumped method that can be applied to real time control algorithms. This has allowed us to better understand the relationship between accuracy and time constraints. The construction of lumped models has helped us to building expertise in real time simulation that are better for application of control strategies. The study of aeroelastic phenomena requires fluid-structure interaction analysis. In other words, the project will require iterative coupling of finite volume for fluid analysis and finite elements for structural analysis in a complex algorithm having high computational and time requirements. Several upstream studies, thus, became essential to optimize computations and avoid simulations with insufficient accuracy or too large resources. In the first place, several software solutions have been studied with regard to their abilities to solve aerodynamic and aeroelastic problems. These studies allowed us to conclude on the advantages of using ANSYS software whilst coupling its structural module with its fluid module, CFX. In order to master this very precise but not so user-friendly software and to calibrate it, we have simulated dynamic stall cases on an S809 airfoil. The choice of these cases was motivated by the availability of experimental results. At that stage, emphasis was laid on the calibration of the study domain, the mesh size, the turbulence models and the

  11. Fluid sampling tool

    DOEpatents

    Garcia, Anthony R.; Johnston, Roger G.; Martinez, Ronald K.

    1999-05-25

    A fluid sampling tool for sampling fluid from a container. The tool has a fluid collecting portion which is drilled into the container wall, thereby affixing it to the wall. The tool may have a fluid extracting section which withdraws fluid collected by the fluid collecting section. The fluid collecting section has a fluted shank with an end configured to drill a hole into a container wall. The shank has a threaded portion for tapping the borehole. The shank is threadably engaged to a cylindrical housing having an inner axial passageway sealed at one end by a septum. A flexible member having a cylindrical portion and a bulbous portion is provided. The housing can be slid into an inner axial passageway in the cylindrical portion and sealed to the flexible member. The bulbous portion has an outer lip defining an opening. The housing is clamped into the chuck of a drill, the lip of the bulbous section is pressed against a container wall until the shank touches the wall, and the user operates the drill. Wall shavings (kerf) are confined in a chamber formed in the bulbous section as it folds when the shank advances inside the container. After sufficient advancement of the shank, an o-ring makes a seal with the container wall.

  12. FRACTURING FLUID CHARACTERIZATION FACILITY

    SciTech Connect

    Subhash Shah

    2000-08-01

    Hydraulic fracturing technology has been successfully applied for well stimulation of low and high permeability reservoirs for numerous years. Treatment optimization and improved economics have always been the key to the success and it is more so when the reservoirs under consideration are marginal. Fluids are widely used for the stimulation of wells. The Fracturing Fluid Characterization Facility (FFCF) has been established to provide the accurate prediction of the behavior of complex fracturing fluids under downhole conditions. The primary focus of the facility is to provide valuable insight into the various mechanisms that govern the flow of fracturing fluids and slurries through hydraulically created fractures. During the time between September 30, 1992, and March 31, 2000, the research efforts were devoted to the areas of fluid rheology, proppant transport, proppant flowback, dynamic fluid loss, perforation pressure losses, and frictional pressure losses. In this regard, a unique above-the-ground fracture simulator was designed and constructed at the FFCF, labeled ''The High Pressure Simulator'' (HPS). The FFCF is now available to industry for characterizing and understanding the behavior of complex fluid systems. To better reflect and encompass the broad spectrum of the petroleum industry, the FFCF now operates under a new name of ''The Well Construction Technology Center'' (WCTC). This report documents the summary of the activities performed during 1992-2000 at the FFCF.

  13. Micromachined Fluid Inertial Sensors

    PubMed Central

    Liu, Shiqiang; Zhu, Rong

    2017-01-01

    Micromachined fluid inertial sensors are an important class of inertial sensors, which mainly includes thermal accelerometers and fluid gyroscopes, which have now been developed since the end of the last century for about 20 years. Compared with conventional silicon or quartz inertial sensors, the fluid inertial sensors use a fluid instead of a solid proof mass as the moving and sensitive element, and thus offer advantages of simple structures, low cost, high shock resistance, and large measurement ranges while the sensitivity and bandwidth are not competitive. Many studies and various designs have been reported in the past two decades. This review firstly introduces the working principles of fluid inertial sensors, followed by the relevant research developments. The micromachined thermal accelerometers based on thermal convection have developed maturely and become commercialized. However, the micromachined fluid gyroscopes, which are based on jet flow or thermal flow, are less mature. The key issues and technologies of the thermal accelerometers, mainly including bandwidth, temperature compensation, monolithic integration of tri-axis accelerometers and strategies for high production yields are also summarized and discussed. For the micromachined fluid gyroscopes, improving integration and sensitivity, reducing thermal errors and cross coupling errors are the issues of most concern. PMID:28216569

  14. Fluid sampling tool

    DOEpatents

    Garcia, A.R.; Johnston, R.G.; Martinez, R.K.

    1999-05-25

    A fluid sampling tool is described for sampling fluid from a container. The tool has a fluid collecting portion which is drilled into the container wall, thereby affixing it to the wall. The tool may have a fluid extracting section which withdraws fluid collected by the fluid collecting section. The fluid collecting section has a fluted shank with an end configured to drill a hole into a container wall. The shank has a threaded portion for tapping the borehole. The shank is threadably engaged to a cylindrical housing having an inner axial passageway sealed at one end by a septum. A flexible member having a cylindrical portion and a bulbous portion is provided. The housing can be slid into an inner axial passageway in the cylindrical portion and sealed to the flexible member. The bulbous portion has an outer lip defining an opening. The housing is clamped into the chuck of a drill, the lip of the bulbous section is pressed against a container wall until the shank touches the wall, and the user operates the drill. Wall shavings (kerf) are confined in a chamber formed in the bulbous section as it folds when the shank advances inside the container. After sufficient advancement of the shank, an o-ring makes a seal with the container wall. 6 figs.

  15. Micromachined Fluid Inertial Sensors.

    PubMed

    Liu, Shiqiang; Zhu, Rong

    2017-02-14

    Micromachined fluid inertial sensors are an important class of inertial sensors, which mainly includes thermal accelerometers and fluid gyroscopes, which have now been developed since the end of the last century for about 20 years. Compared with conventional silicon or quartz inertial sensors, the fluid inertial sensors use a fluid instead of a solid proof mass as the moving and sensitive element, and thus offer advantages of simple structures, low cost, high shock resistance, and large measurement ranges while the sensitivity and bandwidth are not competitive. Many studies and various designs have been reported in the past two decades. This review firstly introduces the working principles of fluid inertial sensors, followed by the relevant research developments. The micromachined thermal accelerometers based on thermal convection have developed maturely and become commercialized. However, the micromachined fluid gyroscopes, which are based on jet flow or thermal flow, are less mature. The key issues and technologies of the thermal accelerometers, mainly including bandwidth, temperature compensation, monolithic integration of tri-axis accelerometers and strategies for high production yields are also summarized and discussed. For the micromachined fluid gyroscopes, improving integration and sensitivity, reducing thermal errors and cross coupling errors are the issues of most concern.

  16. Positionsbestimmung des Unternehmens: Interne und externe Analyse

    NASA Astrophysics Data System (ADS)

    Bergmann, Lars; Crespo, Isabel; Portmann, Stefan

    Die Initiierung und Lenkung von Maßnahmen zur integrierten Modernisierung zielen auf die Verbesserung der Wettbewerbsfähigkeit eines Unternehmens ab. Damit diese Maßnahmen zielgerichtet die Wettbewerbsfähigkeit verbessern können, ist Wissen über die bestehende Wettbewerbsfähigkeit sowie über die bestehenden Fähigkeiten eine zentrale Voraussetzung. Eine zielgerichtete Auswahl problemadäquater Maßnahmen zur Verbesserung der Wettbewerbsfähigkeit bedarf daher im Vorfeld einer Bewertung der aktuellen Situation des Unternehmens im Sinne einer Positionsbestimmung. Erst wenn die internen Stärken und Schwächen sowie die externen Chancen und Risiken identifiziert sind, kann ein ganzheitliches Bild von der Position eines Unternehmens in seiner Umwelt gewonnen werden. Auf Basis der Kenntnisse über die Position des Unternehmens können anschließend zielgerichtet Maßnahmen ausgewählt werden, die einen Beitrag zur Verbesserung der Wettbewerbsfähigkeit des Unternehmens haben. Damit kommt der Positionsbestimmung als initialer Schritt des Prozesses der strategischen Unternehmensplanung eine zentrale Bedeutung im Rahmen der integrierten Modernisierung zu. Erfolgt die Auswahl von Maßnahmen ohne eine vorherige Positionsbestimmung, also lediglich auf Basis drängender Probleme, so besteht die Gefahr einer unbedachten und nur auf das "hier und heute“ bezogenen Schwerpunktbildung ohne Berücksichtigung der mittel- und langfristigen Ziele des Unternehmens.

  17. Fundamentals of fluid sealing

    NASA Technical Reports Server (NTRS)

    Zuk, J.

    1976-01-01

    The fundamentals of fluid sealing, including seal operating regimes, are discussed and the general fluid-flow equations for fluid sealing are developed. Seal performance parameters such as leakage and power loss are presented. Included in the discussion are the effects of geometry, surface deformations, rotation, and both laminar and turbulent flows. The concept of pressure balancing is presented, as are differences between liquid and gas sealing. Mechanisms of seal surface separation, fundamental friction and wear concepts applicable to seals, seal materials, and pressure-velocity (PV) criteria are discussed.

  18. Fundamentals of fluid lubrication

    NASA Technical Reports Server (NTRS)

    Hamrock, Bernard J.

    1991-01-01

    The aim is to coordinate the topics of design, engineering dynamics, and fluid dynamics in order to aid researchers in the area of fluid film lubrication. The lubrication principles that are covered can serve as a basis for the engineering design of machine elements. The fundamentals of fluid film lubrication are presented clearly so that students that use the book will have confidence in their ability to apply these principles to a wide range of lubrication situations. Some guidance on applying these fundamentals to the solution of engineering problems is also provided.

  19. Supercritical fluid extraction

    DOEpatents

    Wai, Chien M.; Laintz, Kenneth

    1994-01-01

    A method of extracting metalloid and metal species from a solid or liquid material by exposing the material to a supercritical fluid solvent containing a chelating agent. The chelating agent forms chelates that are soluble in the supercritical fluid to allow removal of the species from the material. In preferred embodiments, the extraction solvent is supercritical carbon dioxide and the chelating agent is a fluorinated or lipophilic crown ether or fluorinated dithiocarbamate. The method provides an environmentally benign process for removing contaminants from industrial waste without using acids or biologically harmful solvents. The chelate and supercritical fluid can be regenerated, and the contaminant species recovered, to provide an economic, efficient process.

  20. Geophysical fluid flow experiment

    NASA Technical Reports Server (NTRS)

    Broome, B. G.; Fichtl, G.; Fowlis, W.

    1979-01-01

    The essential fluid flow processes associated with the solar and Jovian atmospheres will be examined in a laboratory experiment scheduled for performance on Spacelab Missions One and Three. The experimental instrumentation required to generate and to record convective fluid flow is described. Details of the optical system configuration, the lens design, and the optical coatings are described. Measurement of thermal gradient fields by schlieren techniques and measurement of fluid flow velocity fields by photochromic dye tracers is achieved with a common optical system which utilizes photographic film for data recording. Generation of the photochromic dye tracers is described, and data annotation of experimental parameters on the film record is discussed.

  1. Space Station fluid resupply

    NASA Astrophysics Data System (ADS)

    Winters, Al

    Viewgraphs on space station fluid resupply are presented. Space Station Freedom is resupplied with supercritical O2 and N2 for the ECLSS and USL on a 180 day resupply cycle. Resupply fluids are stored in the subcarriers on station between resupply cycles and transferred to the users as required. ECLSS contingency fluids (O2 and N2) are supplied and stored on station in a gaseous state. Efficiency and flexibility are major design considerations. Subcarrier approach allows multiple manifest combinations. Growth is achieved by adding modular subcarriers.

  2. Multiphase fluid characterization system

    SciTech Connect

    Sinha, Dipen N.

    2014-09-02

    A measurement system and method for permitting multiple independent measurements of several physical parameters of multiphase fluids flowing through pipes are described. Multiple acoustic transducers are placed in acoustic communication with or attached to the outside surface of a section of existing spool (metal pipe), typically less than 3 feet in length, for noninvasive measurements. Sound speed, sound attenuation, fluid density, fluid flow, container wall resonance characteristics, and Doppler measurements for gas volume fraction may be measured simultaneously by the system. Temperature measurements are made using a temperature sensor for oil-cut correction.

  3. Magnetic Fluids--Part 1.

    ERIC Educational Resources Information Center

    Hoon, S. R.; Tanner, B. K.

    1985-01-01

    Basic physical concepts of importance in understanding magnetic fluids (fine ferromagnetic particles suspended in a liquid) are discussed. They include home-made magnetic fluids, stable magnetic fluids, and particle surfactants. (DH)

  4. Basic fluid system trainer

    DOEpatents

    Semans, Joseph P.; Johnson, Peter G.; LeBoeuf, Jr., Robert F.; Kromka, Joseph A.; Goron, Ronald H.; Hay, George D.

    1993-01-01

    A trainer, mounted and housed within a mobile console, is used to teach and reinforce fluid principles to students. The system trainer has two centrifugal pumps, each driven by a corresponding two-speed electric motor. The motors are controlled by motor controllers for operating the pumps to circulate the fluid stored within a supply tank through a closed system. The pumps may be connected in series or in parallel. A number of valves are also included within the system to effect different flow paths for the fluid. In addition, temperature and pressure sensing instruments are installed throughout the closed system for measuring the characteristics of the fluid, as it passes through the different valves and pumps. These measurements are indicated on a front panel mounted to the console, as a teaching aid, to allow the students to observe the characteristics of the system.

  5. Lighter fluid poisoning

    MedlinePlus

    ... in lighter fluids are called hydrocarbons. They include: Benzene Butane Hexamine Lacolene Naptha Propane Where Found Various ... PA: Elsevier Saunders; 2014:chap 158. Mirkin DB. Benzene and related aromatic hydrocarbons. In: Shannon MW, Borron ...

  6. Polymer Fluid Dynamics.

    ERIC Educational Resources Information Center

    Bird, R. Byron

    1980-01-01

    Problems in polymer fluid dynamics are described, including development of constitutive equations, rheometry, kinetic theory, flow visualization, heat transfer studies, flows with phase change, two-phase flow, polymer unit operations, and drag reduction. (JN)

  7. Well servicing fluid

    SciTech Connect

    Liao, A.

    1991-07-02

    This patent describes a well servicing fluid. It comprises an aqueous medium from about 0.2 to about 5 pounds per barrel of a partially hydrolyzed homopolymer of acrylamide having an average molecular weight greater than 1 million, and a calcium-controlling additive. It comprises from about 0.1 to about 2.5 pounds per barrel of the fluid of an alkali metal bicarbonate, from about 0.1 to about 2.5 pounds per barrel of the fluid of a water-soluble, carboxylic acid, and from about 0.1 to about 1.5 pounds per barrel of the fluid of a terpolymer containing from about 40 to about 70% by weight acrylamide, from about 20 to about 40% by weight of an acrylic acid and from about 5 to about 20% by weight of 2-acrylamido-2-methylpropanesulfonic acid, the terpolymer having an average molecular weight of from about 5 to about 10 million.

  8. Pericardial fluid Gram stain

    MedlinePlus

    ... a bacterial infection. The Gram stain method is one of the most commonly used techniques for the rapid diagnosis of bacterial infections. How the Test is Performed A sample of fluid will be taken from the sac ...

  9. Improved perfluoroalkylether fluid development

    NASA Technical Reports Server (NTRS)

    Jones, W. R., Jr.; Paciorek, K.; Nakahara, J.; Smythe, M.; Kratzer, R.

    1986-01-01

    The feasibility of transforming a commercial linear perfluoroalkylether fluid into a material stable in the presence of metals and metal alloys in oxidizing atmospheres at 300 C without the loss of the desirable viscosity temperature characteristics was determined. The approach consisted of thermal oxidative treatment in the presence of catalyst to remove weak links, followed by transformation of the created functional groups into phospha-s-triazine linkages. It it found that the experimental material obtained in 66% yield from the commercial fluid exhibits, over an 8 hr period at 300 C in the presence of Ti(4Al, 4Mn) alloy, thermal oxidative stability better by a factor of 2.6x1000 based on volatiles evolved than the commercial product. The viscosity and molecular weight of the developed fluid are unchanged and are essentially identical with the commercial material. No metal corrosion occurs with the experimental fluid at 300 C.

  10. Culture - joint fluid

    MedlinePlus

    Joint fluid culture ... fungi, or viruses grow. This is called a culture. If these germs are detected, other tests may ... is no special preparation needed for the lab culture. How to prepare for the removal of joint ...

  11. Our World: Fluid Shift

    NASA Video Gallery

    Learn about the circulatory system and how gravity aids blood flow in our bodies here on Earth. Find out how NASA flight surgeons help the astronauts deal with the fluid shift that happens during s...

  12. Cerebrospinal fluid culture

    MedlinePlus

    ... Alternative Names Culture - CSF; Spinal fluid culture; CSF ... In: McPherson RA, Pincus MR, eds. Henry's Clinical Diagnosis and Management by Laboratory Methods . 23d ed. Philadelphia, PA: Elsevier; ...

  13. Windshield washer fluid

    MedlinePlus

    ... support, including oxygen, breathing tube through the mouth (intubation), and breathing machine (ventilator) Blood and urine tests ... Methanol, the main ingredient in windshield washing fluid, is extremely ... As little as 2 tablespoons (30 milliliters) can be deadly ...

  14. Pericardial Fluid Analysis

    MedlinePlus

    ... this test may be used to help detect tuberculosis (TB) . Less commonly ordered tests for infectious diseases, ... fluid in a person with symptoms that suggest tuberculosis means it is likely that person has a ...

  15. Fluid pumping apparatus

    DOEpatents

    West, Phillip B.

    2006-01-17

    A method and apparatus suitable for coupling seismic or other downhole sensors to a borehole wall in high temperature and pressure environments. In one embodiment, one or more metal bellows mounted to a sensor module are inflated to clamp the sensor module within the borehole and couple an associated seismic sensor to a borehole wall. Once the sensing operation is complete, the bellows are deflated and the sensor module is unclamped by deflation of the metal bellows. In a further embodiment, a magnetic drive pump in a pump module is used to supply fluid pressure for inflating the metal bellows using borehole fluid or fluid from a reservoir. The pump includes a magnetic drive motor configured with a rotor assembly to be exposed to borehole fluid pressure including a rotatable armature for driving an impeller and an associated coil under control of electronics isolated from borehole pressure.

  16. Fluid management system technology discipline

    NASA Technical Reports Server (NTRS)

    Symons, E. Patrick

    1990-01-01

    Viewgraphs on fluid management system technology discipline for Space Station Freedom are presented. Topics covered include: subcritical cryogenic storage and transfer; fluid handling; and components and instrumentation.

  17. Cross-Correlating DES and SPT

    NASA Astrophysics Data System (ADS)

    Baxter, Eric

    2017-01-01

    The Dark Energy Survey (DES) and the South Pole Telescope (SPT) provide a uniquely powerful combination of overlapping optical imaging and cosmic microwave background (CMB) data. Cross-correlations between DES and SPT are expected to arise from several physical effects, including gravitational lensing, the Sunyaev-Zel'dovich (SZ) effect, and the Integrated Sachs-Wolfe effect. The resultant correlations contain information not accessible to either experiment on its own. Measurement of these correlations offers several exciting possibilities, such as improved cosmological parameter constraints, improved understanding of systematics affecting the two experiments, and calibration of the masses of galaxy clusters at high redshift. In this talk I will summarize recent results obtained by cross-correlating early DES data with data from the SPT-SZ survey and will discuss prospects for future cross-correlation measurements with these two surveys.

  18. Dynamic DDES On DES Type Grid

    NASA Astrophysics Data System (ADS)

    Yin, Zifei; Durbin, Paul

    2014-11-01

    A dynamic procedure allows a DES formulation that we developed to adjustCDES for different flow configurations. Similarly to the dynamic Smagorinsky model, the grid is required to be fine enough to resolve a significant portion of the inertial range. In some cases, that requirement conflicts with the goal of DES to cut down computing cost. The current effort is therefore to determine a properCDES value by approximately recovering some unresolved small scales from primary, filtered solution. Repeated test filtering is adopted here to compute the approximation of the unfiltered solution. The formulation is based on the dynamicl2 w DDES model and different geometries with varies grid resolution are tested to determine the applicability of proposed formultion on DES type grids.

  19. [Diagnosis: synovial fluid analysis].

    PubMed

    Gallo Vallejo, Francisco Javier; Giner Ruiz, Vicente

    2014-01-01

    Synovial fluid analysis in rheumatological diseases allows a more accurate diagnosis in some entities, mainly infectious and microcrystalline arthritis. Examination of synovial fluid in patients with osteoarthritis is useful if a differential diagnosis will be performed with other processes and to distinguish between inflammatory and non-inflammatory forms. Joint aspiration is a diagnostic and sometimes therapeutic procedure that is available to primary care physicians.

  20. Fluid infusion system

    NASA Technical Reports Server (NTRS)

    1974-01-01

    Performance testing carried out in the development of the prototype zero-g fluid infusion system is described and summarized. Engineering tests were performed in the course of development, both on the original breadboard device and on the prototype system. This testing was aimed at establishing baseline system performance parameters and facilitating improvements. Acceptance testing was then performed on the prototype system to verify functional performance. Acceptance testing included a demonstration of the fluid infusion system on a laboratory animal.

  1. Fluid therapy in shock.

    PubMed

    Mandell, D C; King, L G

    1998-05-01

    The goal of treatment for all types of shock is the improvement of tissue perfusion and oxygenation. The mainstay of therapy for hypovolemic and septic shock is the expansion of the intravascular volume by fluid administration, including crystalloids, colloids, and blood products. Frequent physical examinations and monitoring enable the clinician to determine the adequacy of tissue oxygenation and thus the success of the fluid therapy.

  2. Drilling fluid disposal

    SciTech Connect

    Nesbitt, L.E.; Sander, J.A.

    1981-01-01

    This paper attempts to review the effect of the regulatory process on the selection and handling of drilling fluids for proper disposal. It is shown that a maze of regulations and regulatory agencies coupled with uncertainty in interpretation of environmental data and an evolving system of disposal engineering will require industry action to monitor the area and derive a solid engineering basis for disposal of spent drilling fluid. 16 refs.

  3. Etude numerique et experimentale de la reponse vibro-acoustique des structures raidies a des excitations aeriennes et solidiennes

    NASA Astrophysics Data System (ADS)

    Mejdi, Abderrazak

    Les fuselages des avions sont generalement en aluminium ou en composite renforces par des raidisseurs longitudinaux (lisses) et transversaux (cadres). Les raidisseurs peuvent etre metalliques ou en composite. Durant leurs differentes phases de vol, les structures d'avions sont soumises a des excitations aeriennes (couche limite turbulente : TBL, champs diffus : DAF) sur la peau exterieure dont l'energie acoustique produite se transmet a l'interieur de la cabine. Les moteurs, montes sur la structure, produisent une excitation solidienne significative. Ce projet a pour objectifs de developper et de mettre en place des strategies de modelisations des fuselages d'avions soumises a des excitations aeriennes et solidiennes. Tous d'abord, une mise a jour des modeles existants de la TBL apparait dans le deuxieme chapitre afin de mieux les classer. Les proprietes de la reponse vibro-acoustique des structures planes finies et infinies sont analysees. Dans le troisieme chapitre, les hypotheses sur lesquelles sont bases les modeles existants concernant les structures metalliques orthogonalement raidies soumises a des excitations mecaniques, DAF et TBL sont reexamines en premier lieu. Ensuite, une modelisation fine et fiable de ces structures est developpee. Le modele est valide numeriquement a l'aide des methodes des elements finis (FEM) et de frontiere (BEM). Des tests de validations experimentales sont realises sur des panneaux d'avions fournis par des societes aeronautiques. Au quatrieme chapitre, une extension vers les structures composites renforcees par des raidisseurs aussi en composites et de formes complexes est etablie. Un modele analytique simple est egalement implemente et valide numeriquement. Au cinquieme chapitre, la modelisation des structures raidies periodiques en composites est beaucoup plus raffinee par la prise en compte des effets de couplage des deplacements planes et transversaux. L'effet de taille des structures finies periodiques est egalement pris en

  4. Combat Fluid Resuscitation Interoperable Capability (Capacite Interoperable de Liquides de Reanimation en Situation de Combat)

    DTIC Science & Technology

    2010-10-01

    clinique tout en conférant un avantage logistique dans des environnements de combat difficiles. De nouveaux liquides de réanimation sont nécessaires pour...action plan for the design and implementation of an international multi-centre clinical trial to validate the efficacy of hypertonic fluids for...10 DRDC Toronto TR 2010-172 A key challenge of the CFRIC TDP was to establish an international applied research network, requiring the

  5. [Fluid management: estimation of fluid status].

    PubMed

    Renner, Jochen; Broch, Ole; Bein, Berthold

    2012-07-01

    Cardiac filling pressures alone are not appropriate to estimate the effect of a volume challenge on the corresponding change in stroke volume. Dynamic variables of fluid responsiveness have been shown to discriminate with acceptable sensitivity and specificity between responders and non-responders to a volume challenge. However, several clinical confounders have been indentified which potentially influence the predictive power of these variables. Sound knowledge of these confounders and the acknowledgement that there is no unique threshold value for volume optimisation but a considerable "gray zone" is necessary to fully exploit the advantages of functional haemodynamic monitoring.

  6. Fluid loss control differences of crosslinked and linear fracturing fluids

    SciTech Connect

    Zigrye, J.L.; Whitfill, D.L.; Sievert, J.A.

    1983-01-01

    Three fracturing fluids--a crosslinked guar, a delayed hydrating guar, and a linear guar--were tested for fluid loss control at set time intervals while being conditioned in a heated, pressurized flow loop. Each fluid was tested with 3 different fluid loss additive systems: diesel, silica flour, and a combination of diesel and silica flour. The crosslinked system was tested also with 2 additional fluid loss additive systems. These fluids were diesel plus an anionic surfactant and the combination of diesel/silica flour plus the anionic surfactant. These tests show that the fluid loss of crosslinked fracturing fluids is best controlled by using diesel in combination with a surfactant or a properly sized particulate material. The fluid loss of linear fluids is controlled best with particulate additives.

  7. Les applications des faisceaux d'ions dans la physique des polymères

    NASA Astrophysics Data System (ADS)

    Ratier, B.; Moliton, A.; Lucas, B.; Guille, B.; Clamadieu, M.

    1998-06-01

    Experimental configurations of ions beams are illustrated by diagrams in the case of low energy implantation, Reactive Ion Beam Etching (RIBE), Ion Beam Assisted Deposition (IBAD) of molecular layers (or oligomers). Nous présentons les configurations expérimentales (illustrées par des schémas) de trois applications des faisceaux d'ions au traitement physique des polymères : dopage par implantation (cité pour mémoire), gravure par faisceaux d'ions réactifs (RIBE), dépôt des couches moléculaires (ou oligomères) assistés par faisceau (IBAD).

  8. Intravenous Fluid Generation System

    NASA Technical Reports Server (NTRS)

    McQuillen, John; McKay, Terri; Brown, Daniel; Zoldak, John

    2013-01-01

    The ability to stabilize and treat patients on exploration missions will depend on access to needed consumables. Intravenous (IV) fluids have been identified as required consumables. A review of the Space Medicine Exploration Medical Condition List (SMEMCL) lists over 400 medical conditions that could present and require treatment during ISS missions. The Intravenous Fluid Generation System (IVGEN) technology provides the scalable capability to generate IV fluids from indigenous water supplies. It meets USP (U.S. Pharmacopeia) standards. This capability was performed using potable water from the ISS; water from more extreme environments would need preconditioning. The key advantage is the ability to filter mass and volume, providing the equivalent amount of IV fluid: this is critical for remote operations or resource- poor environments. The IVGEN technology purifies drinking water, mixes it with salt, and transfers it to a suitable bag to deliver a sterile normal saline solution. Operational constraints such as mass limitations and lack of refrigeration may limit the type and volume of such fluids that can be carried onboard the spacecraft. In addition, most medical fluids have a shelf life that is shorter than some mission durations. Consequently, the objective of the IVGEN experiment was to develop, design, and validate the necessary methodology to purify spacecraft potable water into a normal saline solution, thus reducing the amount of IV fluids that are included in the launch manifest. As currently conceived, an IVGEN system for a space exploration mission would consist of an accumulator, a purifier, a mixing assembly, a salt bag, and a sterile bag. The accumulator is used to transfer a measured amount of drinking water from the spacecraft to the purifier. The purifier uses filters to separate any air bubbles that may have gotten trapped during the drinking water transfer from flowing through a high-quality deionizing cartridge that removes the impurities in

  9. Improved perfluoroalkylether fluid development

    NASA Technical Reports Server (NTRS)

    Paciorek, K. L.; Masuda, S. R.; Nakahara, J. H.; Kratzer, R. H.

    1987-01-01

    The objective of this program was to optimize and scale up the linear perfluoroalkylether stabilization process and to provide test data regarding the fluids' thermal oxidative stability in the presence of metal alloys. The stabilization of Fomblin Z-25 was scaled up to 300 g of fluid. The modified fluid was stable at 316 C in oxygen in the presence of M-50 alloy for more than 24 hrs but less than 40 hrs; the amount of volatiles produced after 24 hrs was 5.5 mg/g. In the presence of Ti(4Al,4Mn) alloy, under the above conditions, following an exposure of 24 hrs, the amount of volatiles formed was 6.2 mg/g; 56 hrs exposure yielded 13.9 mg/g. The commercial fluid at 288 C (in oxygen) in the presence of M-50 after 15 hrs of exposure decomposed extensively, 342 mg/g; in the presence of Ti(4Al,4Mn) alloy after only 8 hrs at 288 C, the amount of volatiles was 191 mg/g. Formulation of the commercial fluid with C2PN3 additive was not as effective as the stabilization processing. All the perfluoroalkylether fluids studied were stable in nitrogen at 343 C. The thermal oxidative stability in the absence of metal alloys varied, with Aflunox exhibiting the best behavior. All the fluids were degraded in oxygen at 316 C during 24 hrs exposure to Ti(4Al,4Mn) alloy with the exception of a perfluoroalkylether substituted triazine and the modified Z-25.

  10. Orbital Fluid Transfer System

    NASA Technical Reports Server (NTRS)

    Johnston, A. S., (Nick); Ryder, Mel; Tyler, Tony R.

    1998-01-01

    An automated fluid and power interface system needs to be developed for future space missions which require on orbit consumable replenishment. Current method of fluid transfer require manned vehicles and extravehicular activity. Currently the US does not have an automated capability for consumable transfer on-orbit. This technology would benefit both Space Station and long duration satellites. In order to provide this technology the Automated Fluid Interface System (AFIS) was developed. The AFIS project was an advanced development program aimed at developing a prototype satellite servicer for future space operations. This mechanism could transfer propellants, cryogens, fluids, gasses, electrical power, and communications from a tanker unit to the orbiting satellite. The development of this unit was a cooperative effort between Marshall Space Flight Center in Huntsville, Alabama, and Moog, Inc. in East Aurora, New York. An engineering model was built and underwent substantial development testing at Marshall Space Flight Center (MSFC). While the AFIS is not suitable for spaceflight, testing and evaluation of the AFIS provided significant experience which would be beneficial in building a flight unit. The lessons learned from testing the AFIS provided the foundation for the next generation fluid transfer mechanism, the Orbital Fluid Transfer System (OFTS). The OFTS project was a study contract with MSFC and Moog, Inc. The OFTS was designed for the International Space Station (ISS), but its flexible design could used for long duration satellite missions and other applications. The OFTS was designed to be used after docking. The primary function was to transfer bipropellants and high pressure gases. The other items addressed by this task included propellant storage, hardware integration, safety and control system issues. A new concept for high pressure couplings was also developed. The results of the AFIS testing provided an excellent basis for the OFTS design. The OFTS

  11. La structure des liquides simples et des alliages liquides métalliques

    NASA Astrophysics Data System (ADS)

    Simonet, V.; Bellissent, R.

    2003-09-01

    De par le caractère isotrope des interactions et leur courte portée, les liquides métalliques ont longtemps été considérés comme des systèmes modèles pouvant être décrits par un arrangement aléatoire de sphères dures. Ceci a été confirmé par l'allure des premières fonctions de distribution de paires déterminées par diffusion de RX ou de neutrons à la précision près des expériences de l'époque. Néanmoins, cette image a tout d'abord été révisée pour le cas des alliages métalliques dont les fonctions de distribution de paires ont révélé un ordre local plus complexe à cause des affinités chimiques entre espèces différentes. Grâce à la possibilité actuelle de mesurer des facteurs de structure de bien meilleure qualité, la question de la nature de l'ordre local et du degré d'isotropie des interactions peut se poser même dans le cas des liquides simples ou dans le cas d'alliages présentant à priori peu d'ordre chimique. Dans ce cadre, l'ordre local icosaédrique est particulièrement intéressant puisque l'icosaèdre est un agrégat très compact et, bien que présentant des liaisons directionnelles, très proche d'une configuration isotrope. La mise en évidence de ce type d'ordre local est présentée pour deux types de liquides : les liquides surfondus dans lesquels un ordre local icosaédrique a été prédit pour expliquer les propriétés de surfusion, et les liquides en équilibre avec des quasicristaux qui présentent un ordre local icosaédrique.

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

    NASA Astrophysics Data System (ADS)

    Sotomayor Cruz, Cristian Daniel

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

  13. Amniotic fluid embolism

    PubMed Central

    Kaur, Kiranpreet; Bhardwaj, Mamta; Kumar, Prashant; Singhal, Suresh; Singh, Tarandeep; Hooda, Sarla

    2016-01-01

    Amniotic fluid embolism (AFE) is one of the catastrophic complications of pregnancy in which amniotic fluid, fetal cells, hair, or other debris enters into the maternal pulmonary circulation, causing cardiovascular collapse. Etiology largely remains unknown, but may occur in healthy women during labour, during cesarean section, after abnormal vaginal delivery, or during the second trimester of pregnancy. It may also occur up to 48 hours post-delivery. It can also occur during abortion, after abdominal trauma, and during amnio-infusion. The pathophysiology of AFE is not completely understood. Possible historical cause is that any breach of the barrier between maternal blood and amniotic fluid forces the entry of amniotic fluid into the systemic circulation and results in a physical obstruction of the pulmonary circulation. The presenting signs and symptoms of AFE involve many organ systems. Clinical signs and symptoms are acute dyspnea, cough, hypotension, cyanosis, fetal bradycardia, encephalopathy, acute pulmonary hypertension, coagulopathy etc. Besides basic investigations lung scan, serum tryptase levels, serum levels of C3 and C4 complements, zinc coproporphyrin, serum sialyl Tn etc are helpful in establishing the diagnosis. Treatment is mainly supportive, but exchange transfusion, extracorporeal membrane oxygenation, and uterine artery embolization have been tried from time to time. The maternal prognosis after amniotic fluid embolism is very poor though infant survival rate is around 70%. PMID:27275041

  14. Boiler using combustible fluid

    DOEpatents

    Baumgartner, H.; Meier, J.G.

    1974-07-03

    A fluid fuel boiler is described comprising a combustion chamber, a cover on the combustion chamber having an opening for introducing a combustion-supporting gaseous fluid through said openings, means to impart rotation to the gaseous fluid about an axis of the combustion chamber, a burner for introducing a fluid fuel into the chamber mixed with the gaseous fluid for combustion thereof, the cover having a generally frustro-conical configuration diverging from the opening toward the interior of the chamber at an angle of between 15/sup 0/ and 55/sup 0/; means defining said combustion chamber having means defining a plurality of axial hot gas flow paths from a downstream portion of the combustion chamber to flow hot gases into an upstream portion of the combustion chamber, and means for diverting some of the hot gas flow along paths in a direction circumferentially of the combustion chamber, with the latter paths being immersed in the water flow path thereby to improve heat transfer and terminating in a gas outlet, the combustion chamber comprising at least one modular element, joined axially to the frustro-conical cover and coaxial therewith. The modular element comprises an inner ring and means of defining the circumferential, radial, and spiral flow paths of the hot gases.

  15. Fluid Mechanics: The Pamphlet

    NASA Astrophysics Data System (ADS)

    Variano, Evan

    2012-11-01

    One impediment to student learning in introductory fluid mechanics courses is that the fundamental laws of physics can become lost in the ``noise'' of dozens of semi-empirical equations describing special cases. This can be exacerbated by trends in textbooks and other teaching media. This talk will explore a minimalist approach, whereby the entire content of introductory fluids is distilled to a single 1-page pamphlet, designed to emphasize the governing equations and their near-universal applicability. We are particularly interested in hearing feedback from the audience on ways to further distill the content while keeping it accessible and useful. To further emphasize the difference between the fundamental laws and the many specific cases, we have begun assembling a complementary resource: a field guide to fluid phenomena, which mixes the approach of Van Dyke's book with a standard field guide. This is designed to emphasize that there is a ``zoology'' of fluid phenomena, to which the same small set of fundamental laws has been applied repeatedly. These materials may be useful in helping AP Physics teachers cover fluid mechanics, which is an under-utilized opportunity to introduce young scientists to our field of study.

  16. Fluid driven recipricating apparatus

    SciTech Connect

    Whitehead, John C.

    1997-01-01

    An apparatus comprising a pair of fluid driven pump assemblies in a back-to-back configuration to yield a bi-directional pump. Each of the pump assemblies includes a piston or diaphragm which divides a chamber therein to define a power section and a pumping section. An intake-exhaust valve is connected to each of the power sections of the pump chambers, and function to direct fluid, such as compressed air, into the power section and exhaust fluid therefrom. At least one of the pistons or diaphragms is connected by a rod assembly which is constructed to define a signal valve, whereby the intake-exhaust valve of one pump assembly is controlled by the position or location of the piston or diaphragm in the other pump assembly through the operation of the rod assembly signal valve. Each of the pumping sections of the pump assemblies are provided with intake and exhaust valves to enable filling of the pumping section with fluid and discharging fluid therefrom when a desired pressure has been reached.

  17. Fluid driven reciprocating apparatus

    SciTech Connect

    Whitehead, J.C.

    1997-04-01

    An apparatus is described comprising a pair of fluid driven pump assemblies in a back-to-back configuration to yield a bi-directional pump. Each of the pump assemblies includes a piston or diaphragm which divides a chamber therein to define a power section and a pumping section. An intake-exhaust valve is connected to each of the power sections of the pump chambers, and function to direct fluid, such as compressed air, into the power section and exhaust fluid therefrom. At least one of the pistons or diaphragms is connected by a rod assembly which is constructed to define a signal valve, whereby the intake-exhaust valve of one pump assembly is controlled by the position or location of the piston or diaphragm in the other pump assembly through the operation of the rod assembly signal valve. Each of the pumping sections of the pump assemblies are provided with intake and exhaust valves to enable filling of the pumping section with fluid and discharging fluid therefrom when a desired pressure has been reached. 13 figs.

  18. Fluid-loop reaction system

    NASA Technical Reports Server (NTRS)

    Lurie, Boris J. (Inventor); Schier, J. Alan (Inventor); Iskenderian, Theodore C. (Inventor)

    1991-01-01

    An improved fluid actuating system for imparting motion to a body such as a spacecraft is disclosed. The fluid actuating system consists of a fluid mass that may be controllably accelerated through at least one fluid path whereby an opposite acceleration is experienced by the spacecraft. For full control of the spacecraft's orientation, the system would include a plurality of fluid paths. The fluid paths may be circular or irregular, and the fluid paths may be located on the interior or exterior of the spacecraft.

  19. Fluorescent fluid interface position sensor

    DOEpatents

    Weiss, Jonathan D.

    2004-02-17

    A new fluid interface position sensor has been developed, which is capable of optically determining the location of an interface between an upper fluid and a lower fluid, the upper fluid having a larger refractive index than a lower fluid. The sensor functions by measurement, of fluorescence excited by an optical pump beam which is confined within a fluorescent waveguide where that waveguide is in optical contact with the lower fluid, but escapes from the fluorescent waveguide where that waveguide is in optical contact with the upper fluid.

  20. Effets des electrons secondaires sur l'ADN

    NASA Astrophysics Data System (ADS)

    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. Fiabilité des structures mécaniques adaptatives: effet de la panne des actionneurs ou des capteurs sur la stabilité

    NASA Astrophysics Data System (ADS)

    Fall, H.; Charon, W.; Kouta, R.

    2002-12-01

    Ces dernières décennies, des activités significatives dans le monde étaient dirigées autour du contrôle actif. Le but de ces recherches était essentiellement d'améliorer les performances, la fiabilité et la sécurité des systèmes. Notamment dans le cas des structures soumises à des vibrations aléatoires. D'importants travaux ont été consacré à l'utilisation des “matériaux intelligents” comme capteurs et actionneurs. Cette article propose l'analyse de la fiabilité des systèmes mécaniques en étudiant les pannes des actionneurs ou des capteurs. L'effet de ces pannes sur la stabilité et la performance du système y est démontré. Les méthodologies de conception y sont rappelées. Des exemples numériques sont fournis à travers le contrôle d'un panneau sous chargement dynamique pour illustrer la méthode proposée.

  2. Fluid lubricated bearing construction

    DOEpatents

    Dunning, John R.; Boorse, Henry A.; Boeker, Gilbert F.

    1976-01-01

    1. A fluid lubricated thrust bearing assembly comprising, in combination, a first bearing member having a plain bearing surface, a second bearing member having a bearing surface confronting the bearing surface of said first bearing member and provided with at least one spiral groove extending inwardly from the periphery of said second bearing member, one of said bearing members having an axial fluid-tight well, a source of fluid lubricant adjacent to the periphery of said second bearing member, and means for relatively rotating said bearing members to cause said lubricant to be drawn through said groove and to flow between said bearing surfaces, whereby a sufficient pressure is built up between said bearing surfaces and in said well to tend to separate said bearing surfaces.

  3. Hazardous fluid leak detector

    DOEpatents

    Gray, Harold E.; McLaurin, Felder M.; Ortiz, Monico; Huth, William A.

    1996-01-01

    A device or system for monitoring for the presence of leaks from a hazardous fluid is disclosed which uses two electrodes immersed in deionized water. A gas is passed through an enclosed space in which a hazardous fluid is contained. Any fumes, vapors, etc. escaping from the containment of the hazardous fluid in the enclosed space are entrained in the gas passing through the enclosed space and transported to a closed vessel containing deionized water and two electrodes partially immersed in the deionized water. The electrodes are connected in series with a power source and a signal, whereby when a sufficient number of ions enter the water from the gas being bubbled through it (indicative of a leak), the water will begin to conduct, thereby allowing current to flow through the water from one electrode to the other electrode to complete the circuit and activate the signal.

  4. Computational astrophysical fluid dynamics

    NASA Technical Reports Server (NTRS)

    Norman, Michael L.; Clarke, David A.; Stone, James M.

    1991-01-01

    The field of astrophysical fluid dynamics (AFD) is described as an emerging discipline which derives historically from both the theory of stellar evolution and space plasma physics. The fundamental physical assumption behind AFD is that fluid equations of motion accurately describe the evolution of plasmas on scales that are large in comparison with particle interaction length scales. Particular attention is given to purely fluid models of large-scale astrophysical plasmas. The role of computer simulation in AFD research is also highlighted and a suite of general-purpose application codes for AFD research is discussed. The codes are called ZEUS-2D and ZEUS-3D and solve the equations of AFD in two and three dimensions, respectively, in several coordinate geometries for general initial and boundary conditions. The topics of bipolar outflows from protostars, galactic superbubbles and supershells, and extragalactic radio sources are addressed.

  5. Universal fluid droplet ejector

    DOEpatents

    Lee, E.R.; Perl, M.L.

    1999-08-24

    A droplet generator comprises a fluid reservoir having a side wall made of glass or quartz, and an end cap made from a silicon plate. The end cap contains a micromachined aperture through which the fluid is ejected. The side wall is thermally fused to the end cap, and no adhesive is necessary. This means that the fluid only comes into contact with the side wall and the end cap, both of which are chemically inert. Amplitudes of drive pulses received by reservoir determine the horizontal displacements of droplets relative to the ejection aperture. The drive pulses are varied such that the dropper generates a two-dimensional array of vertically-falling droplets. Vertical and horizontal inter-droplet spacings may be varied in real time. Applications include droplet analysis experiments such as Millikan fractional charge searches and aerosol characterization, as well as material deposition applications. 8 figs.

  6. Universal fluid droplet ejector

    DOEpatents

    Lee, Eric R.; Perl, Martin L.

    1999-08-24

    A droplet generator comprises a fluid reservoir having a side wall made of glass or quartz, and an end cap made from a silicon plate. The end cap contains a micromachined aperture through which the fluid is ejected. The side wall is thermally fused to the end cap, and no adhesive is necessary. This means that the fluid only comes into contact with the side wall and the end cap, both of which are chemically inert. Amplitudes of drive pulses received by reservoir determine the horizontal displacements of droplets relative to the ejection aperture. The drive pulses are varied such that the dropper generates a two-dimensional array of vertically-falling droplets. Vertical and horizontal interdroplet spacings may be varied in real time. Applications include droplet analysis experiments such as Millikan fractional charge searches and aerosol characterization, as well as material deposition applications.

  7. Transverse axis fluid turbine

    SciTech Connect

    Brenneman, B.

    1983-11-15

    A fluid turbine, the rotation axis of which is transverse to the direction of fluid flow, has at least two blade assemblies mounted for rotation about the rotation axis. Each blade assembly includes a streamlined elongated blade having a span parallel to the rotation axis. Each blade is pivotable about a pivot axis parallel to and spaced from the rotation axis. The pivot axis is located circumferentially ahead of the blade center of pressure with respect to the direction of turbine rotation. Each blade assembly is so constructed that its center of mass is located either at its pivot axis or circumferentially at its pivot axis and radially outboard of its pivot axis.

  8. On Gyroviscous Fluids

    NASA Astrophysics Data System (ADS)

    Morrison, Philip J.; Lingam, Manasvi

    2014-11-01

    Fluid models involving gyroviscous effects, whereby momentum is transported while conserving energy, are of interest for plasma, astrophysical, and condensed matter systems. Such fluids can be viewed as possessing intrinsic angular momentum. We present a systematic method for constructing such models from an action principle formalism that allows for an unambiguous means for introducing these effects, instead of ad-hoc phenomenological prescriptions. We also apply Noether's theorem to obtain the appropriate conserved quantities for these models. Supported by U.S. Department of Energy Contract No. DE-FG05-80ET-53088.

  9. Triclinic Fluid Order

    NASA Astrophysics Data System (ADS)

    Chattham, Nattaporn; Korblova, Eva; Shao, Renfan; Walba, David M.; Maclennan, Joseph E.; Clark, Noel A.

    2010-02-01

    Among the condensed phases, those of lowest point group symmetry are the triclinic crystals, which have only the identity element or the identity and inversion elements. Such low symmetry is stabilized by the specificity of molecular interaction, which is weakened with increasing disorder, so that known phases with fluid degrees of freedom are more symmetric. Here we report triclinic order, appearing as a broken symmetry in a single, isolated, fluid smectic liquid crystal layer freely suspended in air, showing that none of its principal dielectric axes lies either normal or parallel to the layer plane.

  10. Triclinic fluid order.

    PubMed

    Chattham, Nattaporn; Korblova, Eva; Shao, Renfan; Walba, David M; Maclennan, Joseph E; Clark, Noel A

    2010-02-12

    Among the condensed phases, those of lowest point group symmetry are the triclinic crystals, which have only the identity element or the identity and inversion elements. Such low symmetry is stabilized by the specificity of molecular interaction, which is weakened with increasing disorder, so that known phases with fluid degrees of freedom are more symmetric. Here we report triclinic order, appearing as a broken symmetry in a single, isolated, fluid smectic liquid crystal layer freely suspended in air, showing that none of its principal dielectric axes lies either normal or parallel to the layer plane.

  11. Electrorheological Fluids: Aerospace Applications

    NASA Technical Reports Server (NTRS)

    Parmar, D. S.; Eftekhari, A.; Belvin, K. W.; Singh, J. J.

    1996-01-01

    Electrorheological fluids (ERF) are an intriguing class of non-Newtonian industrial fluids. They consist of fine dielectric particles suspended in liquids of low dielectric constants. The objectives of this research were to select a particulate system such that: (1) its density can be varied to match that of the selected liquid, and (2) the dielectric constant of the particles and the liquids should be such that the critical fields needed for asymptotic increase in viscosity are less than or equal to 10 KV/cm. Synthetic Zeolite particles were selected as the solute/suspensions. Octoil oil was selected as the solvent. The results are summarized here.

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

    DTIC Science & Technology

    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...existing 4.6 Resistance des avions. AIR 2(4E L - length of obstacle H - height/depth of obstacle Single obstacle Repeated obstacles (STOL aircraft

  13. Determination des Parametres Atmospheriques des Etoiles Naines Blanches de Type DB

    NASA Astrophysics Data System (ADS)

    Beauchamp, Alain

    1995-01-01

    Les etoiles naines blanches dont les spectres visibles sont domines par des raies fortes d'helium neutre sont subdivisees en trois classes, DB (raies d'helium neutre seulement), DBA (raies d'helium neutre et d'hydrogene) et DBZ (raies d'helium neutre et d'elements lourds). Nous analysons trois echantillons de spectres observes de ces types de naines blanches. Les echantillons consistent, respectivement, de 48 spectres dans le domaine du visible (3700-5100 A). 24 dans l'ultraviolet (1200-3100 A) et quatre dans la partie rouge du visible (5100-6900) A). Parmi les objets de l'echantillon visible, nous identifions quatre nouvelles DBA, ainsi que deux nouvelles DBZ, auparavant classees DB. L'analyse nous permet de determiner spectroscopiquement les parametres atmospheriques, soit la temperature effective, la gravite de surface, ainsi que l'abondance relative de l'hydrogene, N(H)/N(He), dans le cas des DBA. Pour les objets plus chauds que ~15,000 K, la gravite de surface determinee est fiable, et nous obtenons les masses stellaires avec une relation masse -rayon theorique. Les exigences propres a l'analyse de ces objets ont requis d'importantes ameliorations dans la modelisation de leurs atmospheres et distributions de flux de radiation emis par ces derniers. Nous avons inclus dans les modeles d'atmospheres, pour la premiere fois a notre connaissance, les effets dus a la molecule He_sp{2 }{+}, ainsi que l'equation d'etat de Hummer et Mihalas (1988), qui tient compte des perturbations entre particules dans le calcul des populations des differents niveaux atomiques. Nous traitons la convection dans le cadre de la theorie de la longueur de melange. Trois grilles de modeles d'atmospheres a l'ETL (equilibre thermodynamique local) ont ete produites, pour un ensemble de temperatures effectives, gravites de surface et abondances d'hydrogene couvrant les proprietes des etoiles de nos echantillons; elles sont caracterisees par differentes parametrisations appelees, respectivement

  14. Profil epidemiologique des brulures d'enfants admis au Centre National des Brules, Maroc

    PubMed Central

    Zahid, A.; Atannaz, J.; Alaoui, M.; Rafik, A.; Ezzoubi, M.; Diouri, M.; Chlihi, A.; Bahechar, N.; Boukind, E.H.

    2011-01-01

    Summary Ce travail rétrospectif analyse les particularités épidémiologiques de 543 cas de brûlures d'enfants, représentant 45,7% des admissions de notre centre, en vue de déterminer les éléments pouvant contribuer à renforcer la prévention, qui reste le traitement de choix de cette pathologie. La moyenne d'âge est de 4,25 ans avec une prédilection pour la tranche d'âge d'un à cinq ans, avec 42,5% des cas. Une atteinte masculine est retrouvée dans 63,5% des cas. La brûlure survient à domicile dans 85,1% et accidentellement dans 95% des cas. Les brûlures thermiques représentent 96,5% des causes dominées par les liquides dans 69,3% des cas. La surface cutanée brûlée est ≥ 20% dans 52,3%. La brûlure intéresse essentiellement les membres supérieurs (79,1%). 56,8% des enfants sont transférés par d'autres hôpitaux et le délai de prise en charge hospitalière est supérieur à 6 heures dans 65,5%. Le taux de mortalité a été de 13,2%. PMID:22639559

  15. Low temperature fluid blender

    NASA Technical Reports Server (NTRS)

    Repas, G. A.

    1971-01-01

    Blender supplies hydrogen at temperatures from 289 deg K to 367 deg K. Hydrogen temperature is controlled by using blender to combine flow from liquid hydrogen tank /276 deg K/ and gaseous hydrogen cylinder /550 deg K/. Blenders are applicable where flow of controlled low-temperature fluid is desired.

  16. Drilling fluid thinner

    SciTech Connect

    Patel, B.

    1989-06-27

    A drilling fluid additive is described comprising a mixture of: (a) a sulfoalkylated tannin and (b) chromium acetate selected from the group consisting of chromium (III) acetate and chromium (II) acetate, wherein the chromium acetate is present in a weight ratio of the chromium acetate to the sulfoalkylated tannin in the range of from about 1:20 to about 1:1.

  17. Turbulent scaling in fluids

    SciTech Connect

    Ecke, R.; Li, Ning; Chen, Shiyi; Liu, Yuanming

    1996-11-01

    This is the final report of a three-year, Laboratory-Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). The project was a study of turbulence in fluids that are subject to different body forces and to external temperature gradients. Our focus was on the recent theoretical prediction that the Kolomogorov picture of turbulence may need to be modified for turbulent flows driven by buoyancy and subject to body forces such as rotational accelerations. Models arising from this research are important in global climate modeling, in turbulent transport problems, and in the fundamental understanding of fluid turbulence. Experimentally, we use (1) precision measurements of heat transport and local temperature; (2) flow visualization using digitally- enhanced optical shadowgraphs, particle-image velocimetry, thermochromic liquid-crystal imaging, laser-doppler velocimetry, and photochromic dye imaging; and (3) advanced image- processing techniques. Our numerical simulations employ standard spectral and novel lattice Boltzmann algorithms implemented on parallel Connection Machine computers to simulate turbulent fluid flow. In laboratory experiments on incompressible fluids, we measure probability distribution functions and two-point spatial correlations of temperature T and velocity V (both T-T and V-T correlations) and determine scaling relations for global heat transport with Rayleigh number. We also explore the mechanism for turbulence in thermal convection and the stability of the thermal boundary layer.

  18. Fluid dynamics test method

    NASA Technical Reports Server (NTRS)

    Gayman, W. H.

    1974-01-01

    Test method and apparatus determine fluid effective mass and damping in frequency range where effective mass may be considered as total mass less sum of slosh masses. Apparatus is designed so test tank and its mounting yoke are supported from structural test wall by series of flexures.

  19. Cryogenic fluid management experiment

    NASA Technical Reports Server (NTRS)

    Eberhardt, R. N.; Bailey, W. J.; Fester, D. A.

    1981-01-01

    The cryogenic fluid management experiment (CFME), designed to characterize subcritical liquid hydrogen storage and expulsion in the low-q space environment, is discussed. The experiment utilizes a fine mesh screen fluid management device to accomplish gas-free liquid expulsion and a thermodynamic vent system to intercept heat leak and control tank pressure. The experiment design evolved from a single flight prototype to provision for a multimission (up to 7) capability. A detailed design of the CFME, a dynamic test article, and dedicated ground support equipment were generated. All materials and parts were identified, and components were selected and specifications prepared. Long lead titanium pressurant spheres and the flight tape recorder and ground reproduce unit were procured. Experiment integration with the shuttle orbiter, Spacelab, and KSC ground operations was coordinated with the appropriate NASA centers, and experiment interfaces were defined. Phase 1 ground and flight safety reviews were conducted. Costs were estimated for fabrication and assembly of the CFME, which will become the storage and supply tank for a cryogenic fluid management facility to investigate fluid management in space.

  20. Relativistic viscoelastic fluid mechanics.

    PubMed

    Fukuma, Masafumi; Sakatani, Yuho

    2011-08-01

    A detailed study is carried out for the relativistic theory of viscoelasticity which was recently constructed on the basis of Onsager's linear nonequilibrium thermodynamics. After rederiving the theory using a local argument with the entropy current, we show that this theory universally reduces to the standard relativistic Navier-Stokes fluid mechanics in the long time limit. Since effects of elasticity are taken into account, the dynamics at short time scales is modified from that given by the Navier-Stokes equations, so that acausal problems intrinsic to relativistic Navier-Stokes fluids are significantly remedied. We in particular show that the wave equations for the propagation of disturbance around a hydrostatic equilibrium in Minkowski space-time become symmetric hyperbolic for some range of parameters, so that the model is free of acausality problems. This observation suggests that the relativistic viscoelastic model with such parameters can be regarded as a causal completion of relativistic Navier-Stokes fluid mechanics. By adjusting parameters to various values, this theory can treat a wide variety of materials including elastic materials, Maxwell materials, Kelvin-Voigt materials, and (a nonlinearly generalized version of) simplified Israel-Stewart fluids, and thus we expect the theory to be the most universal description of single-component relativistic continuum materials. We also show that the presence of strains and the corresponding change in temperature are naturally unified through the Tolman law in a generally covariant description of continuum mechanics.

  1. Orbital Fluid Resupply Assessment

    NASA Technical Reports Server (NTRS)

    Eberhardt, Ralph N.

    1989-01-01

    Orbital fluid resupply can significantly increase the cost-effectiveness and operational flexibility of spacecraft, satellites, and orbiting platforms and observatories. Reusable tankers are currently being designed for transporting fluids to space. A number of options exist for transporting the fluids and propellant to the space-based user systems. The fluids can be transported to space either in the Shuttle cargo bay or using expendable launch vehicles (ELVs). Resupply can thus be accomplished either from the Shuttle bay, or the tanker can be removed from the Shuttle bay or launched on an ELV and attached to a carrier such as the Orbital Maneuvering Vehicle (OMV) or Orbital Transfer Vehicle (OTV) for transport to the user to be serviced. A third option involves locating the tanker at the space station or an unmanned platform as a quasi-permanent servicing facility or depot which returns to the ground for recycling once its tanks are depleted. Current modular tanker designs for monopropellants, bipropellants, and water for space station propulsion are discussed. Superfluid helium tankers are addressed, including trade-offs in tanker sizes, shapes to fit the range of ELVs currently available, and boil-off losses associated with longer-term (greater than 6-month) space-basing. It is concluded that the mixed fleet approach to on-orbit consumables resupply offers significant advantages to the overall logistics requirements.

  2. Time Dependent Fluids

    ERIC Educational Resources Information Center

    Collyer, A. A.

    1974-01-01

    Discusses the flow characteristics of thixotropic and negative thixotropic fluids; various theories underlying the thixotropic behavior; and thixotropic phenomena exhibited in drilling muds, commercial paints, pastes, and greases. Inconsistencies in the terminology used to label time dependent effects are revealed. (CC)

  3. Les effets des interfaces sur les proprietes magnetiques et de transport des multicouches nickel/iron et cobalt/silver

    NASA Astrophysics Data System (ADS)

    Veres, Teodor

    Cette these est consacree a l'etude de l'evolution structurale des proprietes magnetiques et de transport des multicouches Ni/Fe et nanostructures a base de Co et de l'Ag. Dans une premiere partie, essentiellement bibliographique, nous introduisons quelques concepts de base relies aux proprietes magnetiques et de transport des multicouches metalliques. Ensuite, nous presentons une breve description des methodes d'analyse des resultats. La deuxieme partie est consacree a l'etude des proprietes magnetiques et de transport des multicouches ferromagnetiques/ferromagnetiques Ni/Fe. Nous montrerons qu'une interpretation coherente de ces proprietes necessite la prise en consideration des effets des interfaces. Nous nous attacherons a mettre en evidence, a evaluer et a etudier les effets de ces interfaces ainsi que leur evolution, et ce, suite a des traitements thermiques tel que le depot a temperature elevee et l'irradiation ionique. Les analyses correlees de la structure et de la magnetoresistance nous permettront d'emettre des conclusions sur l'influence des couches tampons entre l'interface et le substrat ainsi qu'entre les couches elles-memes sur le comportement magnetique des couches F/F. La troisieme partie est consacree aux systemes a Magneto-Resistance Geante (MRG) a base de Co et Ag. Nous allons etudier l'evolution de la microstructure suite a l'irradiation avec des ions Si+ ayant une energie de 1 MeV, ainsi que les effets de ces changements sur le comportement magnetique. Cette partie debutera par l'analyse des proprietes d'une multicouche hybride, intermediaire entre les multicouches et les materiaux granulaires. Nous analyserons a l'aide des mesures de diffraction, de relaxation superparamagnetique et de magnetoresistance, les evolutions structurales produites par l'irradiation ionique. Nous etablirons des modeles qui nous aideront a interpreter les resultats pour une serie des multicouches qui couvrent un large eventail de differents comportements magnetiques

  4. Ultrasonic fluid densitometry and densitometer

    DOEpatents

    Greenwood, M.S.; Lail, J.C.

    1998-01-13

    The present invention is an ultrasonic fluid densitometer that uses a material wedge having an acoustic impedance that is near the acoustic impedance of the fluid, specifically less than a factor of 11 greater than the acoustic impedance of the fluid. The invention also includes a wedge having at least two transducers for transmitting and receiving ultrasonic signals internally reflected within the material wedge. Density of a fluid is determined by immersing the wedge into the fluid and measuring reflection of ultrasound at the wedge-fluid interface. 6 figs.

  5. Ultrasonic fluid densitometry and densitometer

    DOEpatents

    Greenwood, Margaret S.; Lail, Jason C.

    1998-01-01

    The present invention is an ultrasonic fluid densitometer that uses a material wedge having an acoustic impedance that is near the acoustic impedance of the fluid, specifically less than a factor of 11 greater than the acoustic impedance of the fluid. The invention also includes a wedge having at least two transducers for transmitting and receiving ultrasonic signals internally reflected within the material wedge. Density of a fluid is determined by immersing the wedge into the fluid and measuring reflection of ultrasound at the wedge-fluid interface.

  6. Elaboration de nouvelles approches micromecaniques pour l'optimisation des performances mecaniques des materiaux heterogenes

    NASA Astrophysics Data System (ADS)

    Aboutajeddine, Ahmed

    Les modeles micromecaniques de transition d'echelles qui permettent de determiner les proprietes effectives des materiaux heterogenes a partir de la microstructure sont consideres dans ce travail. L'objectif est la prise en compte de la presence d'une interphase entre la matrice et le renforcement dans les modeles micromecaniques classiques, de meme que la reconsideration des approximations de base de ces modeles, afin de traiter les materiaux multiphasiques. Un nouveau modele micromecanique est alors propose pour tenir compte de la presence d'une interphase elastique mince lors de la determination des proprietes effectives. Ce modele a ete construit grace a l'apport de l'equation integrale, des operateurs interfaciaux de Hill et de la methode de Mori-Tanaka. Les expressions obtenues pour les modules globaux et les champs dans l'enrobage sont de nature analytique. L'approximation de base de ce modele est amelioree par la suite dans un nouveau modele qui s'interesse aux inclusions enrobees avec un enrobage mince ou epais. La resolution utilisee s'appuie sur une double homogeneisation realisee au niveau de l'inclusion enrobee et du materiau. Cette nouvelle demarche, permettra d'apprehender completement les implications des approximations de la modelisation. Les resultats obtenus sont exploites par la suite dans la solution de l'assemblage de Hashin. Ainsi, plusieurs modeles micromecaniques classiques d'origines differentes se voient unifier et rattacher, dans ce travail, a la representation geometrique de Hashin. En plus de pouvoir apprecier completement la pertinence de l'approximation de chaque modele dans cette vision unique, l'extension correcte de ces modeles aux materiaux multiphasiques est rendue possible. Plusieurs modeles analytiques et explicites sont alors proposee suivant des solutions de differents ordres de l'assemblage de Hashin. L'un des modeles explicite apparait comme une correction directe du modele de Mori-Tanaka, dans les cas ou celui ci echoue a

  7. Gaseous species in fluid inclusions: A tracer of fluids and indicator of fluid processes

    SciTech Connect

    Norman, David I.; Moore, Joseph N.; Yonaka, Brad; Musgrave, John

    1996-01-24

    Quantitative bulk analysis of fluid inclusion volatiles measures the composition of trapped geothermal liquids and vapor. Fluid-inclusion gas-analyses may identify fluid boiling and mixing, and the analyses can be used as a fluid tracer. Fluid boiling is indicated by excess gaseous species. Linear arrays of data points on gas ratio diagrams indicate fluid mixing. Nitrogen-argon ratios are used to discriminate atmospheric fiom magmatic volatiles. Crustal components in geothermal fluids are best indicated by concentrations of methane and helium. Methane strongly correlates with other organic compounds, and N2-Ar-CH4 plots are similar to N2-Ar-He diagrams. Alkene to alkane ratios of C2-7 organic species indicate the oxidation state of geothermal fluids. The Geysers inclusion analyses are an example of how inclusion fluids may be used to understand the paleo hydrology of a geothermal system.

  8. A Magellanic origin of the DES dwarfs

    NASA Astrophysics Data System (ADS)

    Jethwa, P.; Erkal, D.; Belokurov, V.

    2016-09-01

    We establish the connection between the Magellanic Clouds (MCs) and the dwarf galaxy candidates discovered in the Dark Energy Survey (DES) by building a dynamical model of the MC satellite populations, based on an extensive suite of tailor-made numerical simulations. Our model takes into account the response of the Galaxy to the MCs infall, the dynamical friction experienced by the MCs and the disruption of the MC satellites by their hosts. The simulation suite samples over the uncertainties in the MC's proper motions, the masses of the MW and the Clouds themselves, and allows for flexibility in the intrinsic volume density distribution of the MC satellites. As a result, we can accurately reproduce the DES satellites' observed positions and kinematics. Assuming that Milky Way (MW) dwarfs follow the distribution of sub-haloes in Λ cold dark matter, we further demonstrate that, of 14 observed satellites, the MW halo contributes fewer than 4(8) of these with 68(95) per cent confidence and that 7(12) DES dwarfs have probabilities greater than 0.7(0.5) of belonging to the Large Magellanic Cloud (LMC). Marginalizing over the entire suite, we constrain the number of Magellanic satellites in the range -7 < MV < -1 which exceed the DES surface brightness threshold at ˜70, and the mass of the LMC around 1011 M⊙. The data also strongly support a first-infall scenario for the LMC. Finally, we give predictions for the line-of-sight velocities and the proper motions of the satellites discovered in the vicinity of the LMC.

  9. Scramjet Thermal Management (Tenue thermique des superstatoreacteurs)

    DTIC Science & Technology

    2010-09-01

    combustion). Airbreathing launchers could typically use hydrogen-fuelled DMR. Less energetic fuels like hydrocarbons could also be used at a Mach number ...failing to comply with a collection of information if it does not display a currently valid OMB control number . 1. REPORT DATE SEP 2010 2. REPORT TYPE...N/A 3. DATES COVERED - 4. TITLE AND SUBTITLE Scramjet Thermal Management (Tenue thermique des superstatoréacteurs) 5a. CONTRACT NUMBER 5b

  10. Peste des petits ruminants in Arabian wildlife.

    PubMed

    Kinne, J; Kreutzer, R; Kreutzer, M; Wernery, U; Wohlsein, P

    2010-08-01

    Recurrence of peste des petits ruminants (PPR) was diagnosed in the United Arabian Emirates in several wild ruminants confirmed by morphological, immunohistochemical, serological and molecular findings. Phylogenetic analysis revealed that the virus strain belongs to lineage IV, which is different to some previously isolated PPR strains from the Arabian Peninsula. This study shows that wild ruminants may play an important epidemiological role as virus source for domestic small ruminants.

  11. Magnetically stimulated fluid flow patterns

    ScienceCinema

    Martin, Jim; Solis, Kyle

    2016-07-12

    Sandia National Laboratories' Jim Martin and Kyle Solis explain research on the effects of magnetic fields on fluid flows and how they stimulate vigorous flows. Fluid flow is a necessary phenomenon in everything from reactors to cooling engines in cars.

  12. Microgravity Fluids for Biology, Workshop

    NASA Technical Reports Server (NTRS)

    Griffin, DeVon; Kohl, Fred; Massa, Gioia D.; Motil, Brian; Parsons-Wingerter, Patricia; Quincy, Charles; Sato, Kevin; Singh, Bhim; Smith, Jeffrey D.; Wheeler, Raymond M.

    2013-01-01

    Microgravity Fluids for Biology represents an intersection of biology and fluid physics that present exciting research challenges to the Space Life and Physical Sciences Division. Solving and managing the transport processes and fluid mechanics in physiological and biological systems and processes are essential for future space exploration and colonization of space by humans. Adequate understanding of the underlying fluid physics and transport mechanisms will provide new, necessary insights and technologies for analyzing and designing biological systems critical to NASAs mission. To enable this mission, the fluid physics discipline needs to work to enhance the understanding of the influence of gravity on the scales and types of fluids (i.e., non-Newtonian) important to biology and life sciences. In turn, biomimetic, bio-inspired and synthetic biology applications based on physiology and biology can enrich the fluid mechanics and transport phenomena capabilities of the microgravity fluid physics community.

  13. Magnetically stimulated fluid flow patterns

    SciTech Connect

    Martin, Jim; Solis, Kyle

    2014-03-06

    Sandia National Laboratories' Jim Martin and Kyle Solis explain research on the effects of magnetic fields on fluid flows and how they stimulate vigorous flows. Fluid flow is a necessary phenomenon in everything from reactors to cooling engines in cars.

  14. Metallization of fluid hydrogen

    SciTech Connect

    Nellis, W.J.; Louis, A.A.; Ashcroft, N.W.

    1997-05-14

    The electrical activity of liquid hydrogen has been measured at the high dynamic pressures, and temperatures that can be achieved with a reverberating shock wave. The resulting data are most naturally interpreted in terms of a continuous transition from a semiconducting to a metallic, largely diatomic fluid, the latter at 140 CPa, (ninefold compression) and 3000 K. While the fluid at these conditions resembles common liquid metals by the scale of its resistivity of 500 micro-ohm-cm, it differs by retaining a strong pairing character, and the precise mechanism by which a metallic state might be attained is still a matter of debate. Some evident possibilities include (i) physics of a largely one-body character, such as a band-overlap transition, (ii) physics of a strong-coupling or many-body character,such as a Mott-Hubbard transition, and (iii) process in which structural changes are paramount.

  15. Drilling fluid filter

    DOEpatents

    Hall, David R.; Fox, Joe; Garner, Kory

    2007-01-23

    A drilling fluid filter for placement within a bore wall of a tubular drill string component comprises a perforated receptacle with an open end and a closed end. A hanger for engagement with the bore wall is mounted at the open end of the perforated receptacle. A mandrel is adjacent and attached to the open end of the perforated receptacle. A linkage connects the mandrel to the hanger. The linkage may be selected from the group consisting of struts, articulated struts and cams. The mandrel operates on the hanger through the linkage to engage and disengage the drilling fluid filter from the tubular drill string component. The mandrel may have a stationary portion comprising a first attachment to the open end of the perforated receptacle and a telescoping adjustable portion comprising a second attachment to the linkage. The mandrel may also comprise a top-hole interface for top-hole equipment.

  16. Body Fluids Monitor

    NASA Technical Reports Server (NTRS)

    Siconolfi, Steven F. (Inventor)

    2000-01-01

    Method and apparatus are described for determining volumes of body fluids in a subject using bioelectrical response spectroscopy. The human body is represented using an electrical circuit. Intra-cellular water is represented by a resistor in series with a capacitor; extra-cellular water is represented by a resistor in series with two parallel inductors. The parallel inductors represent the resistance due to vascular fluids. An alternating, low amperage, multifrequency signal is applied to determine a subject's impedance and resistance. From these data, statistical regression is used to determine a 1% impedance where the subject's impedance changes by no more than 1% over a 25 kHz interval. Circuit component, of the human body circuit are determined based on the 1% impedance. Equations for calculating total body water, extra-cellular water, total blood volume, and plasma volume are developed based on the circuit components.

  17. Continuous fluid level detector

    SciTech Connect

    LeVert, F.E.

    1989-02-21

    A fluid level detector is described which consists of: a junctionless thermocouple cable consisting of two thermoelectric elements enclosed in a metallic sheath wherein a negative resistance temperature coefficient insulant is interpositioned between the thermoelectric elements and the inner surface of the metallic sheath thereby providing electrical insulation and thermal energy transfer between the thermoelectric elements; a metallic sheathed resistance heater, which is used to input thermal energy to the fluid level detector; an outer metallic cylindrical tube capable of being sealed on one end, into which the juctionless thermocouple cable and resistance heater are inserted and held in place by mechanically swaging or drawing, to reduce the outer diameter of the metallic cylindrical tube; separate means for supplying electric currents to the thermoelectric elements and to the resistance heater; and electronic and computing means for measuring the loop resistance of the thermoelectric elements with a temporary junction.

  18. Production of MHD fluid

    DOEpatents

    Lacey, James J.; Kurtzrock, Roy C.; Bienstock, Daniel

    1976-08-24

    A hot gaseous fluid of low ash content, suitable for use in open-cycle MHD (magnetohydrodynamic) power generation, is produced by means of a three-stage process comprising (1) partial combustion of a fossil fuel to produce a hot gaseous product comprising CO.sub.2 CO, and H.sub.2 O, (2) reformation of the gaseous product from stage (1) by means of a fluidized char bed, whereby CO.sub.2 and H.sub.2 O are converted to CO and H.sub.2, and (3) combustion of CO and H.sub.2 from stage (2) to produce a low ash-content fluid (flue gas) comprising CO.sub.2 and H.sub.2 O and having a temperature of about 4000.degree. to 5000.degree.F.

  19. Canonical fluid thermodynamics

    NASA Technical Reports Server (NTRS)

    Schmid, L. A.

    1972-01-01

    The space-time integral of the thermodynamic pressure plays the role of the thermodynamic potential for compressible, adiabatic flow in the sense that the pressure integral for stable flow is less than for all slightly different flows. This stability criterion can be converted into a variational minimum principle by requiring the molar free-enthalpy and the temperature, which are the arguments of the pressure function, to be generalized velocities, that is, the proper-time derivatives of scalar spare-time functions which are generalized coordinates in the canonical formalism. In a fluid context, proper-time differentiation must be expressed in terms of three independent quantities that specify the fluid velocity. This can be done in several ways, all of which lead to different variants (canonical transformations) of the same constraint-free action integral whose Euler-Lagrange equations are just the well-known equations of motion for adiabatic compressible flow.

  20. Oscillating fluid power generator

    DOEpatents

    Morris, David C

    2014-02-25

    A system and method for harvesting the kinetic energy of a fluid flow for power generation with a vertically oriented, aerodynamic wing structure comprising one or more airfoil elements pivotably attached to a mast. When activated by the moving fluid stream, the wing structure oscillates back and forth, generating lift first in one direction then in the opposite direction. This oscillating movement is converted to unidirectional rotational movement in order to provide motive power to an electricity generator. Unlike other oscillating devices, this device is designed to harvest the maximum aerodynamic lift forces available for a given oscillation cycle. Because the system is not subjected to the same intense forces and stresses as turbine systems, it can be constructed less expensively, reducing the cost of electricity generation. The system can be grouped in more compact clusters, be less evident in the landscape, and present reduced risk to avian species.

  1. Dermatomyosite et panniculite: place des immunoglobulines

    PubMed Central

    Abdelhafidh, Nadia Ben; Toujeni, Sana; Kefi, Asma; Bousetta, Najeh; Sayhi, Sameh; Gharsallah, Imen; Othmani, Salah

    2016-01-01

    La panniculite est une maladie inflammatoire du tissu adipeux sous-cutané rarement associée à la dermatomyosite. Elle peut survenir avant, après ou en même temps que l'atteinte musculaire. Dans la plupart des cas, l’évolution de la panniculite et des autres atteintes de la dermatomyosite est favorable sous traitement corticoïde et/ou immunosuppresseur. Nous rapportons le cas d'une patiente âgée de 48 ans ayant présenté des lésions de panniculite précédant de 2 mois les signes musculaires. L'atteinte cutanée était résistante au traitement corticoïde associés aux immunosuppresseurs ce qui a nécessité le recours au traitement par Immunoglobulines polyvalentes permettant ainsi une amélioration à la fois de l'atteinte cutanée et musculaire. PMID:27516827

  2. Sonderverfahren des Spritzgießens

    NASA Astrophysics Data System (ADS)

    Michaeli, Walther; Lettowsky, Christoph

    Das Spritzgießen ist neben der Extrusion das wichtigste Verarbeitungsverfahren für Kunststoffe [1]. Das Verfahren hat sich seit seinen Ursprüngen Ende des 19. Jahrhunderts bis heute stetig weiterentwickelt [2]. In neuerer Zeit steigt die Anzahl komplexer Anwendungen, die die gezielte Kombination verschiedener Funktionalitäten in einem Formteil erfordern. Das Standard-Spritzgießen kann diese Anforderungen immer weniger befriedigen. Daher gewinnen die Sonderverfahren des Spritzgießens zunehmend an Bedeutung [3]. Ihre Anzahl beträgt inzwischen über 100. Die Aufgabe des Anwenders ist es, aus der Vielzahl der möglichen Verfahren, ein anforderungsgerechtes auszuwählen, das sowohl unter technischen wie wirtschaftlichen Gesichtspunkten die optimale Lösung darstellt. Dies setzt die ständige Auseinandersetzung mit Entwicklungstendenzen im Bereich der Spritzgießtechnologie voraus. Daher soll im folgenden Abschnitt ein Überblick über die wichtigsten Spritzgieß-Sonderverfahren gegeben werden.

  3. Newtons Universum. Materialien zur Geschichte des Kraftbegriffes.

    NASA Astrophysics Data System (ADS)

    Mit einem Vorwort von E. Seibold und einer Einführung von W. Neuser. This book is a selection of 15 articles published in the journal "Spektrum der Wissenschaft". The original English versions of the papers were first published in "Scientific American". Contents: 1. Impetustheorie und Intuition in der Physik (M. McCloskey). 2. Mittelalterliche Ursprünge der industriellen Revolution (T. S. Reynolds). 3. Leonardo da Vincis Beiträge zur theoretischen Mechanik (V. Foley, W. Soedel). 4. Nikolaus Kopernikus und Tycho Brahe (O. Gingerich). 5. Keplers Entdeckung der ersten beiden Planetengesetze (C. Wilson). 6. Galileis Entdeckung des Fallgesetzes (S. Drake). 7. Galileis Beobachtung des Neptun (S. Drake, C. T. Kowal). 8. Galileo Galilei und der Schatten des Giordano Bruno (L. S. Lerner, E. A. Gosselin). 9. Der Fall Galilei (O. Gingerich). 10. Newtons Apfel und Galileis "Dialog" (S. Drake). 11. Newtons Gravitationsgesetz - aus Formeln wird eine Idee (I. B. Cohen). 12. Christopher Wren: Astronom und Architekt (H. Dorn, R. Mark). 13. Atomismus und Kräfte in der Geschichte (L. Holliday). 14. Ein Elitezirkel vor 200 Jahren: Die Lunar Society von Birmingham (L. Ritchie-Calder). 15. Sadi Carnot: Technik und Theorie der Dampfmaschine (S. S. Wilson).

  4. The Mechanism of Fluid Resistance

    NASA Technical Reports Server (NTRS)

    Vonkarman, T.; Rubach, H.

    1979-01-01

    The mechanism of fluid resistance within the limit of the square law is presented. It was concluded that the investigations should be extended and completed in two directions, namely: by an investigation of stable vortex configurations in space, and by considering the perfect fluid as the limiting case of a viscous fluid and then limiting the law of vortex of formation with the condition that only those fluid particles which were in contact with the surface of the body can receive rotation.

  5. Numerical Fluid Dynamics.

    DTIC Science & Technology

    1983-01-01

    Bernoulli’s friend Leonhard Euler (1707-83), in two path-breaking papers (1752, 1755). In his second paper, Euler claimed optimistically that "all the theory...the dream of Euler , Poincare, and Hilbert: of making fluid mechanics into a mathematical science, like geometry. Von Neumann, who seems to have...ORIGINATORS LAMB Chaps. KEY PHRASES 1. EULER -LAGRANCE III-VI SOLID BOUNDARIES vs. POTENTIAL FLOW VIII-IX FREE BOUNDARIES INTERFACES, SLIP- STREAMS GRAVITY

  6. Drilling fluid disposal

    SciTech Connect

    Nesbitt, L.E.; Sanders, J.A.

    1981-12-01

    A maze of U.S. regulations and regulatory agencies coupled with uncertainty in interpretation of environmental data and an evolving system of disposal engineering will require industry action to monitor the area and derive a solid engineering basis for disposal of spent drilling fluid. A set of disposal methods with approximate costs is presented to serve as an initial guide for disposal. 16 refs.

  7. The mixing of fluids

    SciTech Connect

    Ottino, J.M.

    1989-01-01

    What do the eruption of Krakatau, the manufacture of puff pastry and the brightness of stars have in common Each involves some aspect of mixing. Mixing also plays a critical role in modern technology. Chemical engineers rely on mixing to ensure that substances react properly, to produce polymer blends that exhibit unique properties and to disperse drag-reducing agents in pipelines. Yet in spite of its of its ubiquity in nature and industry, mixing is only imperfectly under-stood. Indeed, investigators cannot even settle on a common terminology: mixing is often referred to as stirring by oceanographers and geophysicists, as blending by polymer engineers and as agitation by process engineers. Regardless of what the process is called, there is little doubt that it is exceedingly complex and is found in a great variety of systems. In constructing a theory of fluid mixing, for example, one has to take into account fluids that can be miscible or partially miscible and reactive or inert, and flows that are slow and orderly or very fast and turbulent. It is therefore not surprising that no single theory can explain all aspect of mixing in fluids and that straightforward computations usually fail to capture all the important details. Still, both physical experiments and computer simulations can provide insight into the mixing process. Over the past several years the authors and his colleague have taken both approaches in an effort to increase understanding of various aspect of the process-particularly of mixing involving slow flows and viscous fluids such as oils.

  8. Combustion of Solid Propellants (La Combustion des Propergols Solides)

    DTIC Science & Technology

    1991-07-01

    on peut s’interroger sur l’adquation des moyens engages ausceptiblea do se manifester naturellement au cours du A Ia complexit6 du probl~me... capteur d’Helmoltz; de pression lorsque Ia fr~quence vanet. Calcul num~rique et mithode expdrimentale donnent des irdsultats en bon accord, c’cst-i... naturellement , avec des niveaux stabilis~s moddr~s. mod~le de combustion (r~f. 30) et des limites de L’opinion est r~pandue que la segmentation peut l’approche

  9. Inhomogeneites dans le Vent des Etoiles Wolf-Rayet

    NASA Astrophysics Data System (ADS)

    Robert, Carmelle

    1992-01-01

    Des mesures spectroscopiques effectuees avec un haut rapport signal sur bruit et une bonne resolution ont demontre l'existence de regions perturbees en mouvement dans le vent d'etoiles Wolf-Rayet (WR). L'echantillon d'objets etudies ici comprend 9 etoiles WR couvrant differents sous-types WN et WC. De nombreuses petites structures variables superposees au profil des raies d'emission formees dans le vent stellaire signalent la presence des perturbations. L'etude des variations globales des raies et l'examen des micro-structures individuelles ont permis de decrire plusieurs caracteristiques des perturbations. Entre autres, on observe des correlations significatives entre le niveau de variabilite des raies et certains parametres des etoiles qui confirment que le phenomene de variabilite est intrinseque au vent stellaire. En comparant les changements des vitesses radiales et des largeurs equivalentes des differentes raies d'une meme etoile, on conclut que les regions perturbees ont une etendue finie par rapport a l'enveloppe des etoiles. On peut facilement suivre les structures individuelles sur une periode de temps couvrant ~eq8 heures (et peut etre meme 24 heures) avant qu'elles ne disparaissent. Durant ce temps les structures se deplacent en s'eloignant du centre de la raie. A partir des differents comportements notes lors de l'analyse des variations globales et lors de l'examen des structures individuelles, on propose de representer les perturbations par un modele d'inhomogeneites discretes en expansion dans le vent. On suppose simplement que les inhomogeneites emettent comme le vent global (et absorbent aussi si le vent global montre un profil P Cyg). La superposition du graphique de l'acceleration radiale moyenne des inhomogeneites de WR140 en fonction de leur vitesse radiale et du modele theorique d'inhomogeneites qui suivent la loi generale de vitesse donne un taux d'acceleration lent, avec beta >= 3 pour les inhomogeneites de cette etoile. On obtient, entre

  10. Corrosion in supercritical fluids

    SciTech Connect

    Propp, W.A.; Carleson, T.E.; Wai, Chen M.; Taylor, P.R.; Daehling, K.W.; Huang, Shaoping; Abdel-Latif, M.

    1996-05-01

    Integrated studies were carried out in the areas of corrosion, thermodynamic modeling, and electrochemistry under pressure and temperature conditions appropriate for potential applications of supercritical fluid (SCF) extractive metallurgy. Carbon dioxide and water were the primary fluids studied. Modifiers were used in some tests; these consisted of 1 wt% water and 10 wt% methanol for carbon dioxide and of sulfuric acid, sodium sulfate, ammonium sulfate, and ammonium nitrate at concentrations ranging from 0.00517 to 0.010 M for the aqueous fluids. The materials studied were Types 304 and 316 (UNS S30400 and S31600) stainless steel, iron, and AISI-SAE 1080 (UNS G10800) carbon steel. The thermodynamic modeling consisted of development of a personal computer-based program for generating Pourbaix diagrams at supercritical conditions in aqueous systems. As part of the model, a general method for extrapolating entropies and related thermodynamic properties from ambient to SCF conditions was developed. The experimental work was used as a tool to evaluate the predictions of the model for these systems. The model predicted a general loss of passivation in iron-based alloys at SCF conditions that was consistent with experimentally measured corrosion rates and open circuit potentials. For carbon-dioxide-based SCFs, measured corrosion rates were low, indicating that carbon steel would be suitable for use with unmodified carbon dioxide, while Type 304 stainless steel would be suitable for use with water or methanol as modifiers.

  11. Astrophysical fluid dynamics

    NASA Astrophysics Data System (ADS)

    Ogilvie, Gordon I.

    2016-06-01

    > These lecture notes and example problems are based on a course given at the University of Cambridge in Part III of the Mathematical Tripos. Fluid dynamics is involved in a very wide range of astrophysical phenomena, such as the formation and internal dynamics of stars and giant planets, the workings of jets and accretion discs around stars and black holes and the dynamics of the expanding Universe. Effects that can be important in astrophysical fluids include compressibility, self-gravitation and the dynamical influence of the magnetic field that is `frozen in' to a highly conducting plasma. The basic models introduced and applied in this course are Newtonian gas dynamics and magnetohydrodynamics (MHD) for an ideal compressible fluid. The mathematical structure of the governing equations and the associated conservation laws are explored in some detail because of their importance for both analytical and numerical methods of solution, as well as for physical interpretation. Linear and nonlinear waves, including shocks and other discontinuities, are discussed. The spherical blast wave resulting from a supernova, and involving a strong shock, is a classic problem that can be solved analytically. Steady solutions with spherical or axial symmetry reveal the physics of winds and jets from stars and discs. The linearized equations determine the oscillation modes of astrophysical bodies, as well as their stability and their response to tidal forcing.

  12. Supercritical fluids cleaning

    SciTech Connect

    Butner, S.; Hjeresen, D.; Silva, L.; Spall, D.; Stephenson, R.

    1991-01-01

    This paper discusses a proposed multi-party research and development program which seeks to develop supercritical fluid cleaning technology as an alternative to existing solvent cleaning applications. While SCF extraction technology has been in commercial use for several years, the use of these fluids as cleaning agents poses several new technical challenges. Problems inherent in the commercialization of SCF technology include: the cleaning efficacy and compatibility of supercritical working fluids with the parts to be cleaned must be assessed for a variety of materials and components; process parameters and equipment design Have been optimized for extractive applications and must be reconsidered for application to cleaning; and co-solvents and entrainers must be identified to facilitate the removal of polar inorganic and organic contaminants, which are often not well solvated in supercritical systems. The proposed research and development program would address these issues and lead to the development and commercialization of viable SCF-based technology for precision cleaning applications. This paper provides the technical background, program scope, and delineates the responsibilities of each principal participant in the program.

  13. Galilean relativistic fluid mechanics

    NASA Astrophysics Data System (ADS)

    Ván, P.

    2017-01-01

    Single-component nonrelativistic dissipative fluids are treated independently of reference frames and flow-frames. First the basic fields and their balances are derived, then the related thermodynamic relations and the entropy production are calculated and the linear constitutive relations are given. The usual basic fields of mass, momentum, energy and their current densities, the heat flux, pressure tensor and diffusion flux are the time- and spacelike components of the third-order mass-momentum-energy density-flux four-tensor. The corresponding Galilean transformation rules of the physical quantities are derived. It is proved that the non-equilibrium thermodynamic frame theory, including the thermostatic Gibbs relation and extensivity condition and also the entropy production, is independent of the reference frame and also the flow-frame of the fluid. The continuity-Fourier-Navier-Stokes equations are obtained almost in the traditional form if the flow of the fluid is fixed to the temperature. This choice of the flow-frame is the thermo-flow. A simple consequence of the theory is that the relation between the total, kinetic and internal energies is a Galilean transformation rule.

  14. Galilean relativistic fluid mechanics

    NASA Astrophysics Data System (ADS)

    Ván, P.

    2017-03-01

    Single-component nonrelativistic dissipative fluids are treated independently of reference frames and flow-frames. First the basic fields and their balances are derived, then the related thermodynamic relations and the entropy production are calculated and the linear constitutive relations are given. The usual basic fields of mass, momentum, energy and their current densities, the heat flux, pressure tensor and diffusion flux are the time- and spacelike components of the third-order mass-momentum-energy density-flux four-tensor. The corresponding Galilean transformation rules of the physical quantities are derived. It is proved that the non-equilibrium thermodynamic frame theory, including the thermostatic Gibbs relation and extensivity condition and also the entropy production, is independent of the reference frame and also the flow-frame of the fluid. The continuity-Fourier-Navier-Stokes equations are obtained almost in the traditional form if the flow of the fluid is fixed to the temperature. This choice of the flow-frame is the thermo-flow. A simple consequence of the theory is that the relation between the total, kinetic and internal energies is a Galilean transformation rule.

  15. Downhole Fluid Analyzer Development

    SciTech Connect

    Bill Turner

    2006-11-28

    A novel fiber optic downhole fluid analyzer has been developed for operation in production wells. This device will allow real-time determination of the oil, gas and water fractions of fluids from different zones in a multizone or multilateral completion environment. The device uses near infrared spectroscopy and induced fluorescence measurement to unambiguously determine the oil, water and gas concentrations at all but the highest water cuts. The only downhole components of the system are the fiber optic cable and windows. All of the active components--light sources, sensors, detection electronics and software--will be located at the surface, and will be able to operate multiple downhole probes. Laboratory testing has demonstrated that the sensor can accurately determine oil, water and gas fractions with a less than 5 percent standard error. Once installed in an intelligent completion, this sensor will give the operating company timely information about the fluids arising from various zones or multilaterals in a complex completion pattern, allowing informed decisions to be made on controlling production. The research and development tasks are discussed along with a market analysis.

  16. Fluid handling equipment: A compilation

    NASA Technical Reports Server (NTRS)

    1976-01-01

    Devices and techniques used in fluid-handling and vacuum systems are described. Section 1 presents several articles on fluid lines and tubing. Section 2 describes a number of components such as valves, filters, and regulators. The last section contains descriptions of a number of innovative fluid-handling systems.

  17. The Viscosity of Polymeric Fluids.

    ERIC Educational Resources Information Center

    Perrin, J. E.; Martin, G. C.

    1983-01-01

    To illustrate the behavior of polymeric fluids and in what respects they differ from Newtonian liquids, an experiment was developed to account for the shear-rate dependence of non-Newtonian fluids. Background information, procedures, and results are provided for the experiment. Useful in transport processes, fluid mechanics, or physical chemistry…

  18. Microwave Propagation in Dielectric Fluids.

    ERIC Educational Resources Information Center

    Lonc, W. P.

    1980-01-01

    Describes an undergraduate experiment designed to verify quantitatively the effect of a dielectric fluid's dielectric constant on the observed wavelength of microwave radiation propagating through the fluid. The fluid used is castor oil, and results agree with the expected behavior within 5 percent. (Author/CS)

  19. Paternité des articles et intérêts concurrents : une analyse des recommandations aux auteurs des journaux traitant de pratique pharmaceutique

    PubMed Central

    Courbon, Ève; Tanguay, Cynthia; Lebel, Denis; Bussières, Jean-François

    2014-01-01

    RÉSUMÉ Contexte : La présence d’auteurs honorifiques et fantômes ainsi que les intérêts concurrents représentent des difficultés bien documentées, liées à la publication d’articles scientifiques. Il existe des lignes directrices encadrant la rédaction et la publication de manuscrits scientifiques, notamment celles de l’International Committee of Medical Journal Editors (ICMJE). Objectifs : L’objectif principal de cette étude descriptive et transversale visait à recenser les instructions portant sur la paternité des articles et les intérêts concurrents provenant des recommandations aux auteurs des journaux traitant de pratique pharmaceutique. L’objectif secondaire visait à déterminer des mesures correctrices pour une paternité des articles plus transparente. Méthode : La recherche a débuté par l’identification des journaux traitant de pratique pharmaceutique. La consultation des instructions aux auteurs des journaux a permis ensuite de recenser les recommandations destinées à éviter les problèmes de paternité des articles et d’intérêts concurrents. Finalement, les membres de l’équipe de recherche se sont consultés afin de définir des mesures correctrices possibles à l’intention des chercheurs. Résultats : Des 232 journaux traitant de pharmacie, 33 ont été définis comme traitant de pratique pharmaceutique. Un total de 24 (73 %) journaux mentionnaient suivre la politique de l’ICMJE, 14 (42 %) demandaient aux auteurs de remplir un formulaire de déclaration d’intérêts concurrents au moment de la soumission de l’article, 17 (52 %) présentaient une définition de la qualité d’auteur et 5 (15 %) demandaient de détailler les contributions de chaque auteur. Une grille de 40 critères a été élaborée pour définir l’attribution du statut d’auteur. Conclusion : Moins de la moitié des journaux demandait aux auteurs de transmettre un formulaire de déclaration des intérêts concurrents au moment de la

  20. Fluid loss control differences of crosslinked and linear fracturing fluids

    SciTech Connect

    Zigrye, J.L.; Sievert, J.A.; Whitfill, D.L.

    1983-10-01

    Three fracturing fluids-a cross-linked guar, a delayed hydrating guar and a linear guar-were tested for fluid loss control at set time intervals while being conditioned in a heated, pressurized flow loop. Each fluid was tested with three different fluid loss additive systems: diesel, silica flour, and a combination of diesel and silica flour. The cross-linked system was also tested with two additional fluid loss additive systems. They were diesel plus an anionic surfactant and the combination of diesel/silica flour plus the anionic surfactant. These tests show that the fluid loss of cross-linked fracturing fluids is best controlled by using diesel in combination with a surfactant or a properly sized particulate material. The fluid loss of linear fluids is controlled best with particulate additives. Therefore, it is important to take into account the type of fracturing fluid that is being used for a particular job when planning which fluid loss additives to use.

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

    NASA Astrophysics Data System (ADS)

    Savard, Stephane

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

  2. Annual Program Management Report (1990), Des Moines Recreational River and Greenbelt, Des Moines River, Iowa

    DTIC Science & Technology

    1990-12-01

    study are listed below: STUDY MANAGEMENT C111 Jim MIll I SITE PLANNING George Gitter, AICP ECONOMIC AND SOCIAL ANALYSIS Patricia Risser ENVIRONMENTAL...Trail (Raccoon River Segment), Des Moines - The project involves the construction of approximately 42,500 feet of paved multi-purpose trail in the...Federd Fee kwe Sc Am 1000 02000 ~]Lod Area -~ aroraed SCALE FEET Des Moies Recreaond Rvf And Greenbdt U.S. ARMY VNGDIKE DITrWC - ROC BLAND -A MOCK SA’rL0A

  3. Les effets du travail en equipe dans l'apprentissage par projets sur la motivation des etudiantes et des etudiants en formation des ingenieurs

    NASA Astrophysics Data System (ADS)

    Fernandez, Nicolas

    Les representants des secteurs industriels et les, milieux professionnels en Amerique du Nord reprochaient aux universites de former des ingenieurs avec peu d'experience pratique en resolution de problemes et en conception. Quelques programmes de genie ont alors mis en place le travail en equipe dans l'apprentissage par projets. Beaucoup d'ecrits font valoir les benefices de l'apprentissage par projets sur la motivation des etudiants. Or, ces benefices commencent a peine a faire l'objet de recherches visant a produire des donnees probantes a ce sujet. Les travaux sur la motivation en contexte d'apprentissage et les modeles theoriques developpes sont issus d'environnements d'apprentissage marques par l'enseignement magistral. Le modele de la valeur attendue de la tache (Eccles et Wigfield, 1995; Neuville, 2004) et le modele du systeme-groupe (St-Arnaud, 2008) ont ete retenus pour mesurer les effets du travail en equipe dans l'apprentissage par projets sur la motivation. La recherche visait aussi a approfondir et a nuancer la comprehension de la motivation des etudiants universitaires apprenant en contexte innovant. Les sujets constituent des etudiants (n=100) travaillant sur des projets d'integration au cours des trois sessions initiales du programme de genie mecanique d'une universite canadienne. L'analyse de regression multiple revele que les construits de la motivation expliquent un tiers de la variance de l'engagement academique dans la realisation du projet d'integration. Les perceptions de l' "expectancy", de la valeur intrinseque et utilitaire sont les determinants principaux de l'engagement des etudiants. L'analyse de variance multivariee a mesures repetees indique que la motivation des etudiants pour le travail sur les projets d'integration a augmente au cours des trois sessions initiales du parcours de formation. Finalement, malgre l'absence d'interaction significative entre les variables de motivation et de l'equipe, les reponses des sujets indiquent une

  4. Supercritical fluid reverse micelle separation

    DOEpatents

    Fulton, J.L.; Smith, R.D.

    1993-11-30

    A method of separating solute material from a polar fluid in a first polar fluid phase is provided. The method comprises combining a polar fluid, a second fluid that is a gas at standard temperature and pressure and has a critical density, and a surfactant. The solute material is dissolved in the polar fluid to define the first polar fluid phase. The combined polar and second fluids, surfactant, and solute material dissolved in the polar fluid is maintained under near critical or supercritical temperature and pressure conditions such that the density of the second fluid exceeds the critical density thereof. In this way, a reverse micelle system defining a reverse micelle solvent is formed which comprises a continuous phase in the second fluid and a plurality of reverse micelles dispersed in the continuous phase. The solute material is dissolved in the polar fluid and is in chemical equilibrium with the reverse micelles. The first polar fluid phase and the continuous phase are immiscible. The reverse micelles each comprise a dynamic aggregate of surfactant molecules surrounding a core of the polar fluid. The reverse micelle solvent has a polar fluid-to-surfactant molar ratio W, which can vary over a range having a maximum ratio W[sub o] that determines the maximum size of the reverse micelles. The maximum ratio W[sub o] of the reverse micelle solvent is then varied, and the solute material from the first polar fluid phase is transported into the reverse micelles in the continuous phase at an extraction efficiency determined by the critical or supercritical conditions. 27 figures.

  5. Supercritical fluid reverse micelle separation

    DOEpatents

    Fulton, John L.; Smith, Richard D.

    1993-01-01

    A method of separating solute material from a polar fluid in a first polar fluid phase is provided. The method comprises combining a polar fluid, a second fluid that is a gas at standard temperature and pressure and has a critical density, and a surfactant. The solute material is dissolved in the polar fluid to define the first polar fluid phase. The combined polar and second fluids, surfactant, and solute material dissolved in the polar fluid is maintained under near critical or supercritical temperature and pressure conditions such that the density of the second fluid exceeds the critical density thereof. In this way, a reverse micelle system defining a reverse micelle solvent is formed which comprises a continuous phase in the second fluid and a plurality of reverse micelles dispersed in the continuous phase. The solute material is dissolved in the polar fluid and is in chemical equilibrium with the reverse micelles. The first polar fluid phase and the continuous phase are immiscible. The reverse micelles each comprise a dynamic aggregate of surfactant molecules surrounding a core of the polar fluid. The reverse micelle solvent has a polar fluid-to-surfactant molar ratio W, which can vary over a range having a maximum ratio W.sub.o that determines the maximum size of the reverse micelles. The maximum ratio W.sub.o of the reverse micelle solvent is then varied, and the solute material from the first polar fluid phase is transported into the reverse micelles in the continuous phase at an extraction efficiency determined by the critical or supercritical conditions.

  6. Fluid-fluid versus fluid-solid demixing in mixtures of parallel hard hypercubes

    NASA Astrophysics Data System (ADS)

    Lafuente, Luis; Martínez-Ratón, Yuri

    2011-02-01

    It is well known that increase of the spatial dimensionality enhances the fluid-fluid demixing of a binary mixture of hard hyperspheres, i.e. the demixing occurs for lower mixture size asymmetry as compared to the three-dimensional case. However, according to simulations, in the latter dimension the fluid-fluid demixing is metastable with respect to the fluid-solid transition. According to the results obtained from approximations to the equation of state of hard hyperspheres in higher dimensions, the fluid-fluid demixing might become stable for high enough dimension. However, this conclusion is rather speculative since none of these works have taken into account the stability of the crystalline phase (by a minimization of a given density functional, by spinodal calculations or by MC simulations). Of course, the lack of results is justified by the difficulty of performing density functional calculations or simulations in high dimensions and, in particular, for highly asymmetric binary mixtures. In the present work, we will take advantage of a well tested theoretical tool, namely the fundamental measure density functional theory for parallel hard hypercubes (in the continuum and in the hypercubic lattice). With this, we have calculated the fluid-fluid and fluid-solid spinodals for different spatial dimensions. We have obtained, no matter what the dimensionality, the mixture size asymmetry or the polydispersity (included as a bimodal distribution function centered around the asymmetric edge lengths), that the fluid-fluid critical point is always located above the fluid-solid spinodal. In conclusion, these results point to the existence of demixing between at least one solid phase rich in large particles and one fluid phase rich in small ones, preempting a fluid-fluid demixing, independently of the spatial dimension or the polydispersity.

  7. Heat transfer fluids containing nanoparticles

    SciTech Connect

    Singh, Dileep; Routbort, Jules; Routbort, A.J.; Yu, Wenhua; Timofeeva, Elena; Smith, David S.; France, David M.

    2016-05-17

    A nanofluid of a base heat transfer fluid and a plurality of ceramic nanoparticles suspended throughout the base heat transfer fluid applicable to commercial and industrial heat transfer applications. The nanofluid is stable, non-reactive and exhibits enhanced heat transfer properties relative to the base heat transfer fluid, with only minimal increases in pumping power required relative to the base heat transfer fluid. In a particular embodiment, the plurality of ceramic nanoparticles comprise silicon carbide and the base heat transfer fluid comprises water and water and ethylene glycol mixtures.

  8. Fluid bed material transfer method

    DOEpatents

    Pinske, Jr., Edward E.

    1994-01-01

    A fluidized bed apparatus comprising a pair of separated fluid bed enclosures, each enclosing a fluid bed carried on an air distributor plate supplied with fluidizing air from below the plate. At least one equalizing duct extending through sidewalls of both fluid bed enclosures and flexibly engaged therewith to communicate the fluid beds with each other. The equalizing duct being surrounded by insulation which is in turn encased by an outer duct having expansion means and being fixed between the sidewalls of the fluid bed enclosures.

  9. Fluid management: the pharmacoeconomic dimension

    PubMed Central

    2000-01-01

    Cost is a key concern in fluid management. Relatively few data are available that address the comparative total costs of care between different fluid management regimens in particular clinical indications. Relevant costs of fluid-associated morbidity and mortality, including those incurred after intensive care unit or hospital discharge, also need to be considered in evaluating the cost-benefit ratios of administered fluids. Rigorously designed pharmacoeconomic studies are needed to delineate the costs and benefits of various approaches to fluid management. PMID:11255597

  10. Proprietes Adiabatiques des Naines Blanches Pulsantes de Type ZZ Ceti

    NASA Astrophysics Data System (ADS)

    Brassard, Pierre

    1992-01-01

    Cette these a pour but d'etudier les proprietes des oscillation non-radiales des etoiles ZZ Ceti, appelees aussi etoiles DA variables, dans le contexte de la theorie adiabatique des petites oscillations. Ces oscillations sont observables, pour ce type d'etoiles, sous forme de variations periodiques de la luminosite. A partir d'une analyse de modeles stellaires, analyse qui consiste principalement a calculer et a interpreter les periodes d'oscillations des modeles, nous voulons mieux connai tre les proprietes physiques fondamentales des ZZ Ceti. Nous developpons tout d'abord divers outils pour entreprendre cette etude. Apres avoir presente le formalisme mathematique de base decrivant les oscillations non-radiales d'une etoile, nous discutons des difficultes pouvant etre rencontrees dans le calcul de la frequence de Brunt-Vaisala, une quantite fondamentale pour le calcul des periodes d'oscillations. Par la suite, nous developpons un modele theorique simple permettant d'analyser et d'interpreter la structure des periodes calculees (ou observees) en termes des proprietes de structure de l'etoile. Nous presentons aussi les outils numeriques tout a fait originaux utilises pour calculer nos periodes a partir de modeles stellaires. Finalement, nous presentons les resultats d'ensemble de l'analyse de nos modeles, et discutons de l'interpretation des observations de periodes et du taux de variation de ces periodes en termes de structure de l'etoile et de composition du noyau de l'etoile, respectivement. Ces resultats representent l'etude la plus complete a ce jour de la seismologie des naines blanches.

  11. Fluid viscosity under confined conditions

    NASA Astrophysics Data System (ADS)

    Rudyak, V. Ya.; Belkin, A. A.

    2014-12-01

    Closed equations of fluid transfer in confined conditions are constructed in this study using ab initio methods of nonequilibrium statistical mechanics. It is shown that the fluid viscosity is not determined by the fluid properties alone, but becomes a property of the "fluid-nanochannel walls" system as a whole. Relations for the tensor of stresses and the interphase force, which specifies the exchange by momentum of fluid molecules with the channel-wall molecules, are derived. It is shown that the coefficient of viscosity is now determined by the sum of three contributions. The first contribution coincides with the expression for the coefficient of the viscosity of fluid in the bulk being specified by the interaction of fluid molecules with each other. The second contribution has the same structure as the first one but is determined by the interaction of fluid molecules with the channel-wall molecules. Finally, the third contribution has no analog in the usual statistical mechanics of transport processes of a simple fluid. It is associated with the correlation of intermolecular forces of the fluid and the channel walls. Thus, it is established that the coefficient of viscosity of fluid in sufficiently small channels will substantially differ from its bulk value.

  12. Rheological properties of synovial fluids.

    PubMed

    Fam, H; Bryant, J T; Kontopoulou, M

    2007-01-01

    Synovial fluid is the joint lubricant and shock absorber [Semin. Arthritis Rheum. 32 (2002), 10-37] as well as the source of nutrition for articular cartilage. The purpose of the present paper is to provide a comprehensive review of the rheological properties of synovial fluid as they relate to its chemical composition. Given its importance in the rheology of synovial fluid, an overview of the structure and rheology of HA (hyaluronic acid) is presented first. The rheology of synovial fluids is discussed in detail, with a focus on the possible diagnosis of joint pathology based on the observed differences in rheological parameters and trends. The deterioration of viscoelastic properties of synovial fluid in pathological states due to effects of HA concentration and molecular weight is further described. Recent findings pertaining to the composition and rheology of periprosthetic fluid, the fluid that bathes prosthetic joints in vivo are reported.

  13. Magnetic power piston fluid compressor

    NASA Technical Reports Server (NTRS)

    Gasser, Max G. (Inventor)

    1994-01-01

    A compressor with no moving parts in the traditional sense having a housing having an inlet end allowing a low pressure fluid to enter and an outlet end allowing a high pressure fluid to exit is described. Within the compressor housing is at least one compression stage to increase the pressure of the fluid within the housing. The compression stage has a quantity of magnetic powder within the housing, is supported by a screen that allows passage of the fluid, and a coil for selectively providing a magnetic field across the magnetic powder such that when the magnetic field is not present the individual particles of the powder are separated allowing the fluid to flow through the powder and when the magnetic field is present the individual particles of the powder pack together causing the powder mass to expand preventing the fluid from flowing through the powder and causing a pressure pulse to compress the fluid.

  14. Ratcheting fluid with geometric anisotropy

    NASA Astrophysics Data System (ADS)

    Thiria, Benjamin; Zhang, Jun

    2015-02-01

    We investigate a mechanism that effectively transports fluids using vibrational motion imposed onto fluid boundary with anisotropy. In our experiment, two asymmetric, sawtooth-like structures are placed facing each other and form a corrugated fluid channel. This channel is then forced to open and close periodically. Under reciprocal motion, fluid fills in the gap during the expansion phase of the channel and is then forced out during contraction. Since the fluid experiences different impedances when flowing in different directions, the stagnation point that separates flows of two directions changes within each driving period. As a result, fluid is transported unidirectionally. This ratcheting effect of fluid is demonstrated through our measurements and its working principle discussed in some detail.

  15. Engine Fluid Leakage Detection: A Feasibility Study

    DTIC Science & Technology

    2011-07-01

    de détecter tout problème possible lié à la sécurité ou aux performances des moteurs à turbine à gaz d’aéronefs. Le signalement immédiat d’une fuite...l’utilisation d’un concept innovateur de capteurs ultrasoniques. On a évalué s’il était possible d’utiliser des transducteurs ultrasoniques, des...fonctionnement du moteur. Perspectives : Les prochaines étapes de conception d’un dispositif autonome consistent à créer un capteur ayant des capacités

  16. Fluid and Electrolyte Nutrition

    NASA Technical Reports Server (NTRS)

    Lane, Helen W.; Smith, Scott M.; Leach, Carolyn S.; Rice, Barbara L.

    1999-01-01

    Studies of fluid and electrolyte homeostasis have been completed since the early human space flight programs, with comprehensive research completed on the Spacelab Life Sciences missions SLS-1 and SLS-2 flights, and more recently on the Mir 18 mission. This work documented the known shifts in fluids, the decrease in total blood volume, and indications of reduced thirst. Data from these flights was used to evaluate the nutritional needs for water, sodium, and potassium. Interpretations of the data are confounded by the inadequate energy intakes routinely observed during space flight. This in turn results in reduced fluid intake, as food provides approximately 70% water intake. Subsequently, body weight, lean body mass, total body water, and total body potassium may decrease. Given these issues, there is evidence to support a minimum required water intake of 2 L per day. Data from previous Shuttle flights indicated that water intake is 2285 +/- 715 ml/day (mean +/- SD, n=26). There are no indications that sodium intake or homeostasis is compromised during space flight. The normal or low aldosterone and urinary sodium levels suggest adequate sodium intake (4047 +/- 902 mg/day, n=26). Because excessive sodium intake is associated with hypercalciuria, the recommended maximum amount of sodium intake during flight is 3500 mg/day (i.e., similar to the Recommended Dietary Allowance, RDA). Potassium metabolism appears to be more complex. Data indicate loss of body potassium related to muscle atrophy and low dietary intake (2407 +/- 548 mg/day, n=26). Although possibly related to measurement error, the elevations in blood potassium suggest alterations in potassium homeostasis. The space RDA for minimum potassium intake is 3500 mg/day. With the documented inadequate intakes, efforts are being made to increase dietary consumption of potassium.

  17. La modelisation mathematique dans l'enseignement de la chimie des gaz a des eleves de la cinquieme annee du secondaire

    NASA Astrophysics Data System (ADS)

    Gauthier, Diane

    Les problemes d'enseignement de la chimie des gaz parfaits sont donc importants. Si plusieurs etudes ont ete realisees dans le but d'identifier et d'interpreter ces problemes, aucune recherche, a notre connaissance, n'a ete realisee sur l'enseignement des lois sur les gaz parfaits. Notre recherche sur l'enseignement est donc pionniere. Elle a pour objectif general de construire et d'analyser une sequence d'enseignement de la chimie des gaz comportant diverses situations de modelisation mathematique des conduites des gaz. Les principaux objectifs specifiques sont les suivants: (1) identifier et caracteriser les situations qui provoquent une evolution des conceptions naives des eleves, evolution vers des connaissances plus adequate sur les gaz; (2) identifier et caractEriser les situations qui provoquent une evolution des connaissances mathematiques des eleves leur permettant d'interpreter convenablement les resultats des experiences, d'eprouver leurs conceptions, de donner un sens aux notions et aux relations impliquees dans les lois des gaz parfaits, lois de Boyle-Mariotte et Gay-Lussac. Une sequence d'enseignement comportant huit situations est d'eleves de secondaire V. La construction de ces situations est orientee par les recherches sur les conceptions naives des eleves, par les etudes sur l'evolution historique des conceptions sur les gaz et des pratiques scientifiques, ainsi que par les etudes theoriques et empiriques realisees en didactique des sciences et des mathematiques. La methodologie de l'ingenierie didactique (Artigue, 1998) qui constitue une application de la theorie des situations didactiques (Brousseau, 1986) est utilisee dans la construction et l'analyse des situations d'enseignement. Une analyse a priori de chacune des situations d'enseignement est effectuee; elle a pour but dexpliquer les choix des taches qui font partie des situations et de preciser la gestion didactique des situations. Diverses situations d'enseignement de la chimie ont ainsi

  18. Catenaries in viscous fluid

    NASA Astrophysics Data System (ADS)

    Hanna, James; Chakrabarti, Brato

    2015-11-01

    Slender structures live in fluid flows across many scales, from towed instruments to plant blades to microfluidic valves. The present work details a simple model of a flexible structure in a uniform flow. We present analytical solutions for the translating, axially flowing equilibria of strings subjected to a uniform body force and linear drag forces. This is an extension of the classical catenaries to a five-parameter family of solutions, represented as trajectories in angle-curvature ``phase space.'' Limiting cases include neutrally buoyant towed cables and freely sedimenting flexible filaments. Now at University of California, San Diego.

  19. Rotational fluid flow experiment

    NASA Technical Reports Server (NTRS)

    1991-01-01

    This project which began in 1986 as part of the Worcester Polytechnic Institute (WPI) Advanced Space Design Program focuses on the design and implementation of an electromechanical system for studying vortex behavior in a microgravity environment. Most of the existing equipment was revised and redesigned by this project team, as necessary. Emphasis was placed on documentation and integration of the electrical and mechanical subsystems. Project results include reconfiguration and thorough testing of all hardware subsystems, implementation of an infrared gas entrainment detector, new signal processing circuitry for the ultrasonic fluid circulation device, improved prototype interface circuits, and software for overall control of experiment operation.

  20. Electrochemistry in supercritical fluids

    PubMed Central

    Branch, Jack A.; Bartlett, Philip N.

    2015-01-01

    A wide range of supercritical fluids (SCFs) have been studied as solvents for electrochemistry with carbon dioxide and hydrofluorocarbons (HFCs) being the most extensively studied. Recent advances have shown that it is possible to get well-resolved voltammetry in SCFs by suitable choice of the conditions and the electrolyte. In this review, we discuss the voltammetry obtained in these systems, studies of the double-layer capacitance, work on the electrodeposition of metals into high aspect ratio nanopores and the use of metallocenes as redox probes and standards in both supercritical carbon dioxide–acetonitrile and supercritical HFCs. PMID:26574527

  1. Electrochemistry in supercritical fluids.

    PubMed

    Branch, Jack A; Bartlett, Philip N

    2015-12-28

    A wide range of supercritical fluids (SCFs) have been studied as solvents for electrochemistry with carbon dioxide and hydrofluorocarbons (HFCs) being the most extensively studied. Recent advances have shown that it is possible to get well-resolved voltammetry in SCFs by suitable choice of the conditions and the electrolyte. In this review, we discuss the voltammetry obtained in these systems, studies of the double-layer capacitance, work on the electrodeposition of metals into high aspect ratio nanopores and the use of metallocenes as redox probes and standards in both supercritical carbon dioxide-acetonitrile and supercritical HFCs.

  2. Etude des defauts microscopiques et des proprietes optiques, electroniques et magnetiques du compose neodyme cerium oxyde de cuivre

    NASA Astrophysics Data System (ADS)

    Richard, Pierre

    La presente these, qui combine des mesures de diffusion Raman, de transmission infrarouge, de conductivite hyperfrequence et d'interferometrie ultrasonore sur les composes Nd 2-xCexCuO 4, traite des defauts d'oxygene, ainsi que des proprietes optiques, electroniques et magnetiques de ces materiaux. Les resultats experimentaux obtenus sont correles avec plusieurs donnees experimentales disponibles dans la litterature. D'abord, la caracterisation des modes Raman et des niveaux d'energie de champ cristallin de l'ion Nd3+ au moyen de techniques optiques, en fonction du dopage en cerium et du contenu en oxygene, permettent de conclure a la presence de defauts lies a une non-stoechiometrie en oxygene dans ces composes. En effet, des excitations de champ cristallin assignees a des ions Nd3+ en sites irreguliers sont observees, en plus des bandes d'absorption associees aux ions Nd3+ en site regulier, dans les spectres correspondant aux multiplets 4I11/2, 4I13/2 et 4I 15/2 de l'ion Nd3+. Les resultats experimentaux indiquent que, contrairement a la croyance largement repandue, les oxygenes apicaux, bien que presents dans les echantillons dopes, ne sont pas enleves lors du processus de reduction des echantillons necessaire pour faire apparaitre la supraconductivite dans cette famille de cuprates. Au contraire, des lacunes d'oxygene, dont le type varie en fonction du dopage, sont creees lors de ce processus. En particulier, il est montre dans ce travail que la reduction des echantillons dopes de maniere optimale conduit a la creation de lacunes d'oxygene dans les plans CuO2. Les consequences de telles lacunes sont largement discutees. En outre, il est suggere que de telles lacunes sont responsables de la perte de l'ordre antiferromagnetique a longue portee des ions Cu2+. Finalement, l'interaction d'echange anisotrope Nd3+-Cu 2+ dans le compose nondope est caracterisee au moyen de la transmission infrarouge sous champ magnetique. L'eclatement des doublets de Kramers mesure

  3. Etude des chaines de spins par les methodes de la theorie quantique des champs

    NASA Astrophysics Data System (ADS)

    Allen, Dave

    Notre etude porte sur la chaine de spins en zigzag avec dimerisation dans le cas des spins 1/2 et 1. L'echelle de spin ordinaire et la chaine en zigzag simple en sont des cas particuliers. Dans la limite continue, ces systemes sont decrits par des modeles Wess-Zumino-Witten couples. Afin de pouvoir calculer les fonctions de correlation, nous exposons differentes equivalences quantiques permettant de simplifier les calculs. Dans le cas de chaines de spin 1/2, nous demontrons l'equivalence avec un modele de type Gross-Neveu, en fonction de fermions de Majorana; ces fermions decrivent alors les excitations elementaires du systeme. Nous exposons une vision classique de ces excitations afin de voir les mecanismes de confinement des spinons. Dans le cas de chaines de spin 1, l'etude est plus complexe. Nous pouvons decrire le systeme a l'aide de modeles sine-Gordon perturbes par de nombreuses interactions. En se limitant aux plus importantes, nous pouvons expliquer le comportement du gap en fonction du couplage interchaine observe numeriquement.

  4. Acoustic concentration of particles in fluid flow

    DOEpatents

    Ward, Michael D.; Kaduchak, Gregory

    2010-11-23

    An apparatus for acoustic concentration of particles in a fluid flow includes a substantially acoustically transparent membrane and a vibration generator that define a fluid flow path therebetween. The fluid flow path is in fluid communication with a fluid source and a fluid outlet and the vibration generator is disposed adjacent the fluid flow path and is capable of producing an acoustic field in the fluid flow path. The acoustic field produces at least one pressure minima in the fluid flow path at a predetermined location within the fluid flow path and forces predetermined particles in the fluid flow path to the at least one pressure minima.

  5. 75 FR 63714 - Drawbridge Operation Regulation; Des Allemands Bayou, LA

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-10-18

    ... Burlington Northern Santa Fe Railway swing bridge across Des Allemands Bayou, mile 14.0, in St. Charles and... INFORMATION: The Burlington Northern Santa Fe Railway swing span drawbridge across Bayou Des Allemands, mile... tows, fishing vessels and recreational craft. The Burlington Northern Santa Fe Railway requested...

  6. Vers des boites quantiques a base de graphene

    NASA Astrophysics Data System (ADS)

    Branchaud, Simon

    Le graphene est un materiau a base de carbone qui est etudie largement depuis 2004. De tres nombreux articles ont ete publies tant sur les proprietes electroniques, qu'optiques ou mecaniques de ce materiel. Cet ouvrage porte sur l'etude des fluctuations de conductance dans le graphene, et sur la fabrication et la caracterisation de nanostructures gravees dans des feuilles de ce cristal 2D. Des mesures de magnetoresistance a basse temperature ont ete faites pres du point de neutralite de charge (PNC) ainsi qu'a haute densite electronique. On trouve deux origines aux fluctuations de conductance pres du PNC, soit des oscillations mesoscopiques provenant de l'interference quantique, et des fluctuations dites Hall quantique apparaissant a plus haut champ (>0.5T), semblant suivre les facteurs de remplissage associes aux monocouches de graphene. Ces dernieres fluctuations sont attribuees a la charge d'etats localises, et revelent un precurseur a l'effet Hall quantique, qui lui, ne se manifeste pas avant 2T. On arrive a extraire les parametres caracterisant l'echantillon a partir de ces donnees. A la fin de cet ouvrage, on effectue des mesures de transport dans des constrictions et ilots de graphene, ou des boites quantiques sont formees. A partir de ces mesures, on extrait les parametres importants de ces boites quantiques, comme leur taille et leur energie de charge.

  7. 33 CFR 117.439 - Des Allemands Bayou.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 1 2011-07-01 2011-07-01 false Des Allemands Bayou. 117.439 Section 117.439 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements Louisiana § 117.439 Des Allemands Bayou. (a) The...

  8. 33 CFR 117.439 - Des Allemands Bayou.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 33 Navigation and Navigable Waters 1 2014-07-01 2014-07-01 false Des Allemands Bayou. 117.439 Section 117.439 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements Louisiana § 117.439 Des Allemands Bayou. (a) The...

  9. 33 CFR 117.439 - Des Allemands Bayou.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 33 Navigation and Navigable Waters 1 2013-07-01 2013-07-01 false Des Allemands Bayou. 117.439 Section 117.439 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements Louisiana § 117.439 Des Allemands Bayou. (a) The...

  10. 33 CFR 117.439 - Des Allemands Bayou.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Des Allemands Bayou. 117.439 Section 117.439 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements Louisiana § 117.439 Des Allemands Bayou. (a) The...

  11. 33 CFR 117.439 - Des Allemands Bayou.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 33 Navigation and Navigable Waters 1 2012-07-01 2012-07-01 false Des Allemands Bayou. 117.439 Section 117.439 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements Louisiana § 117.439 Des Allemands Bayou. (a) The...

  12. Etude du processus de changement vecu par des familles ayant decide d'adopter volontairement des comportements d'attenuation des changements climatiques

    NASA Astrophysics Data System (ADS)

    Leger, Michel T.

    Les activites humaines energivores telles l'utilisation intensive de l'automobile, la surconsommation de biens et l'usage excessif d'electricite contribuent aux changements climatiques et autres problemes environnementaux. Bien que plusieurs recherches rapportent que l'etre humain est de plus en plus conscient de ses impacts sur le climat de la planete, ces memes recherches indiquent qu'en general, les gens continuent a se comporter de facon non ecologique. Que ce soit a l'ecole ou dans la communaute, plusieurs chercheurs en education relative a l'environnement estiment qu'une personne bien intentionnee est capable d'adopter des comportements plus respectueux de l'environnement. Le but de cette these etait de comprendre le processus d'integration de comportements d'attenuation des changements climatiques dans des familles. A cette fin, nous nous sommes fixe deux objectifs : 1) decrire les competences et les procedes qui favorisent l'adoption de comportements d'attenuation des changements climatiques dans des familles et 2) decrire les facteurs et les dynamiques familiales qui facilitent et limitent l'adoption de comportements d'attenuation des changements climatiques dans des familles. Des familles ont ete invitees a essayer des comportements personnels et collectifs d'attenuation des changements climatiques de sorte a integrer des modes de vie plus ecologiques. Sur une periode de huit mois, nous avons suivi leur experience de changement afin de mieux comprendre comment se produit le processus de changement dans des familles qui decident volontairement d'adopter des comportements d'attenuation des changements climatiques. Apres leur avoir fourni quelques connaissances de base sur les changements climatiques, nous avons observe le vecu de changement des familles durant huit mois d'essais a l'aide de journaux reflexifs, d'entretiens d'explicitation et du journal du chercheur. La these comporte trois articles scientifiques. Dans le premier article, nous presentons une

  13. Fluid lubricated bearing assembly

    DOEpatents

    Boorse, Henry A.; Boeker, Gilbert F.; Menke, John R.

    1976-01-01

    1. A support for a loaded rotatable shaft comprising in combination on a housing having a fluid-tight cavity encasing an end portion of said shaft, a thrust bearing near the open end of said cavity for supporting the axial thrust of said shaft, said thrust bearing comprising a thrust plate mounted in said housing and a thrust collar mounted on said shaft, said thrust plate having a central opening the peripheral portion of which is hermetically sealed to said housing at the open end of said cavity, and means for supplying a fluid lubricant to said thrust bearing, said thrust bearing having a lubricant-conducting path connecting said lubricant supplying means with the space between said thrust plate and collar intermediate the peripheries thereof, the surfaces of said plate and collar being constructed and arranged to inhibit radial flow of lubricant and, on rotation of said thrust collar, to draw lubricant through said path between the bearing surfaces and to increase the pressure therebetween and in said cavity and thereby exert a supporting force on said end portion of said shaft.

  14. Amniotic fluid assessment.

    PubMed

    Smith, C V

    1990-03-01

    The mysterious environment surrounding the fetus for much of his or her life is now being explored with increasing fervor. Assessment of amniotic fluid in the early portion of pregnancy is now possible for fetal karyotype determination. This may permit early diagnosis of abnormal fetuses, increasing the options for patients. As pregnancy progresses, high-resolution ultrasound assessment of amniotic fluid volume is integral to the management of pregnancies at risk for oligohydramnios. Such pregnancies include those who are postdate and those with suspected intrauterine growth retardation. Additional evaluation and ultrasonography are recommended for evaluation of the fetus in this clinical situation. With either hydramnios or oligohydramnios, careful ultrasound assessment of the fetus is essential to rule out significant congenital malformations. Finally, the use of ultrasound-directed amniocentesis in later pregnancy permits an assessment of fetal lung maturity and of the fetus at risk for Rhesus immunization. Attention to detail should increase chances of a successful pregnancy outcome while decreasing neonatal morbidity and mortality.

  15. Fluid injection microvalve

    DOEpatents

    Renzi, Ronald F.

    2005-11-22

    A microvalve for extracting small volume samples into analytical devices, e.g., high pressure liquid chromatography (HPLC) column, includes: a first body having a first interior surface and two or more outlet ports at the first interior surface that are in fluid communication with two or more first channels; a second body having a second interior surface and two or more inlet ports at the second interior surface that are in fluid communication with two or more second channels wherein the outlet ports of the first body are coaxial with the corresponding inlet ports of the second body such that there are at least two sets of coaxial port outlets and port inlets; a plate member, which has a substantially planar first mating surface and a substantially planar second mating surface, that is slidably positioned between the first interior surface and the second interior surface wherein the plate member has at least one aperture that traverses the height of the plate member, and wherein the aperture can be positioned to be coaxial with any of the at least two sets of coaxial port outlets and port inlets; and means for securing the first surface of the first body against the first mating surface and for securing the second surface of the second body against the second mating surface.

  16. Entomological fluid dynamics

    NASA Astrophysics Data System (ADS)

    Bush, John

    2007-11-01

    The world of arthropods (insects and spiders) presents a number of novel fluid mechanics problems on a scale of interest to the microfluidics community. We address a number of such problems, giving particular attention to elucidating and rationalizing natural strategies for water-repellency and fluid transport on a small scale. The rough, hairy integument of water-walking arthropods is well known to be responsible for their water-repellency; we here consider its additional roles in underwater breathing and propulsion along the free surface. When submerged, many arthropods are able to survive by virtue of a thin air bubble trapped along their rough exteriors. The diffusion of dissolved oxygen from the water into the bubble allows it to function as an external lung, and enables certain species to remain underwater indefinitely. By coupling the bubble mechanics and chemistry, we develop criteria for this style of underwater breathing. We further demonstrate that the tilted flexible leg hairs of water-walking arthropods render the leg cuticle directionally anisotropic: contact lines advance most readily towards the leg tips. The dynamical role of the resulting unidirectional adhesion is explored, and yields new insight into the manner in which water-walking arthropods generate thrust, glide and leap from the free surface. Finally, we provide new rationale for the fundamental topological difference in the roughness on plants and insects, and suggest new directions for biomimetic design.

  17. Anisotropie des coefficients de diffusion dans des cristaux liquides discotiques hexagonaux

    NASA Astrophysics Data System (ADS)

    Daoud, M.; Gharbia, M.; Gharbi, A.

    1994-06-01

    The diffusion constants of dyes in several hexagonal discotic liquid crystals are measured and discussed. For all the liquid crystals studied, these constants are anisotropic : the diffusion in the direction parallel to the columns is faster than that in the perpendicular plane (frac{D_allel}{D_perp}>1). The effects of the length and shape of the chains bound to the triphenylene discs are shown. The effect of the dye molecular size is also described. The study of the diffusion coefficients of hexapentoxytriphenylene (C5HET) as a function of temperature has shown that the activation energies along the columns and perpendicular to the columns are comparable. The main features of dye diffusion in the hexagonal columnar liquid crystals studied are similar to those reported in nematic phases. Les mesures des constantes de diffusion de colorants dans plusieurs cristaux liquides discotiques hexagonaux sont présentées et discutées. Pour tous les cristaux liquides étudiés, ces constantes présentent une anisotropie, avec une diffusion plus rapide parallèlement aux colonnes que perpendiculairement à celles-ci (frac{D_allel}{D_perp}>1). Des effets de longueur et de forme des chaînes branchées sur les disques de triphénylène sont mis en évidence. Il en est de même pour la taille des molécules de colorants. L'étude en fonction de la température a montré que dans le cas de l'hexapentoxytriphénylène (C5HET), les énergies d'activation dans les directions parallèle et perpendiculaire aux colonnes sont comparables. Les caractéristiques de la diffusion de colorants dans les cristaux liquides colonnaires hexagonaux étudiés sont semblables à celles des nématiques.

  18. La physique des bulles de champagne Une première approche des processus physico-chimiques liés à l'effervescence des vins de Champagne

    NASA Astrophysics Data System (ADS)

    Liger-Belair, G.

    2002-07-01

    . Because of their geometry and hydrophobic properties, such particles are able to entrap gas pockets during the filling of a flute and to start up the bubble production process. Such particles are responsible for the clockwork and repetitive production of bubbles that rise in-line into the form of elegant bubble trains. This cycle of bubble production at a given nucleation site is characterised by its bubbling frequency. The time needed to reach the moment of bubble detachment depends on the kinetics of the CO2 molecules transfer from the champagne to the gas pocket, but also on the geometrical properties of the given nucleation site. Now, since a collection of particle shapes and sizes exists on the glass wall, the bubbling frequency may also vary from one site to another. Three minutes after pouring, we measured bubbling frequencies ranging from less than 1 Hz up to almost 30 Hz, which means that the most active nucleation sites emit up to 30 bubbles per second. After their detachment from nucleation sites, champagne bubbles rise in-line through the liquid into the form of elegant bubble trains. Since they collect dissolved carbon dioxide molecules, champagne bubbles expand during ascent and therefore constitute an original tool to investigate the dynamics of rising and expanding bubbles. Hydrodynamically speaking, champagne bubbles were found to reach a quasi-stationary stage intermediate between that of a rigid and that a fluid sphere (but nevertheless closer to that of a fluid sphere). This result drastically differs from the result classically observed with bubbles of fixed radii rising in surfactant solutions. Since surfactants progressively adsorb at the bubble surface during the rise, the drag coefficient of a rising bubble of fixed radius progressively increases, and finally reaches the rigid sphere limit when the bubble interface gets completely contaminated. In the case of champagne, since a bubble expands during its rise through the supersaturated liquid, the

  19. Halogen Variations in Apatite of the Lac Des Iles Palladium Deposit, Ontario, Canada

    NASA Astrophysics Data System (ADS)

    Boudreau, A. E.

    2014-12-01

    Analysis of apatite from the Mine Block Intrusion (MBI) of the Lac des Iles Igneous Complex show two pronounced trends in the halogens. Apatite from relatively fresh norite and melanorites from the Pd-sulfide zone contain up to 57 mole % chlorapatite endmember with significant hydroxyapatite component. In contrast, in altered rock (amphibolite and greenschist assemblages) and in the more evolved barren rocks the chlorapatite component is typically less than 10 mole % with wide variation in the F- and OH-endmember components. The latter trend is attributed to Cl loss to degassing and alteration whereas the former is attributed to Cl-enrichment in the ore-bearing rocks. It is suggested that the relatively H2O-rich and intermediate Cl content of the early igneous fluids degassed from the deeper levels of the MBI can explain the high Pd/Pt and Pd/Ir ratios of the deposit. A model is presented in which disseminated Pd-rich sulfide are initially introduced by a high temperature magmatic fluid that also influenced crystallization to produce the gross modal variations of the igneous host rock. This high temperature mineralization event was subsequently modified by the influx of late igneous and country fluids at amphibolite to greenschist conditions.

  20. The Lac Des Iles Palladium Deposit, Ontario, Canada. Part II. Halogen variations in apatite

    NASA Astrophysics Data System (ADS)

    Schisa, Paul; Boudreau, Alan; Djon, Lionnel; Tchalikian, Arnaud; Corkery, John

    2015-03-01

    Analysis of apatite from the Mine Block Intrusion (MBI) of the Lac des Iles Igneous Complex shows two pronounced trends in the halogens. Apatite from relatively fresh norite and melanorites from the Pd-sulfide zone contain up to 57 mol% chlorapatite endmember with significant hydroxyapatite component. In contrast, in altered rock (amphibolite and greenschist assemblages) the chlorapatite component is typically less than 10 mol% with wide variation in the F- and OH-endmember components. The latter trend is attributed to Cl loss to degassing and alteration, whereas the former is attributed to Cl enrichment in the ore-bearing rocks. It is suggested that the relatively H2O-rich and intermediate Cl content of the early igneous fluids degassed from the deeper levels of the MBI can explain the high Pd/Pt and Pd/Ir ratios of the deposit. A model is presented in which disseminated Pd-rich sulfides are initially introduced by a high-temperature magmatic fluid that also influenced crystallization to produce the gross modal variations of the igneous host rock. This high-temperature mineralization event was subsequently modified by the influx of late igneous and country fluids at amphibolite to greenschist conditions.

  1. Suction blister fluid as potential body fluid for biomarker proteins.

    PubMed

    Kool, Jeroen; Reubsaet, Léon; Wesseldijk, Feikje; Maravilha, Raquel T; Pinkse, Martijn W; D'Santos, Clive S; van Hilten, Jacobus J; Zijlstra, Freek J; Heck, Albert J R

    2007-10-01

    Early diagnosis is important for effective disease management. Measurement of biomarkers present at the local level of the skin could be advantageous in facilitating the diagnostic process. The analysis of the proteome of suction blister fluid, representative for the interstitial fluid of the skin, is therefore a desirable first step in the search for potential biomarkers involved in biological pathways of particular diseases. Here, we describe a global analysis of the suction blister fluid proteome as potential body fluid for biomarker proteins. The suction blister fluid proteome was compared with a serum proteome analyzed using identical protocols. By using stringent criteria allowing less than 1% false positive identifications, we were able to detect, using identical experimental conditions and amount of starting material, 401 proteins in suction blister fluid and 240 proteins in serum. As a major result of our analysis we construct a prejudiced list of 34 proteins, relatively highly and uniquely detected in suction blister fluid as compared to serum, with established and putative characteristics as biomarkers. We conclude that suction blister fluid might potentially serve as a good alternative biomarker body fluid for diseases that involve the skin.

  2. Le traitement familial des enfants et des adolescents anorexiques : Des lignes directrices pour le médecin communautaire

    PubMed Central

    Findlay, S; Pinzon, J; Taddeo, D; Katzman, DK

    2010-01-01

    L’anorexie mentale (AM) est une maladie grave qui met la vie en danger et qui fait généralement son apparition pendant l’adolescence. Les données probantes au sujet du traitement optimal de l’AM chez les enfants et les adolescents sont en croissance, mais il reste beaucoup à apprendre. Même si les démarches thérapeutiques actuelles varient au Canada et ailleurs, les données jusqu’à présent indiquent que le traitement familial (TF) est le plus efficace pour les enfants et les adolescents anorexiques. Un élément essentiel du modèle de TF, c’est que les parents sont investis de la responsabilité de rétablir la santé physique de leur enfant et de s’assurer de la reprise complète de son poids. Le médecin qui comprend les principes fondamentaux et la philosophie du TF peut mettre en place les éléments de cette intervention fondée sur des faits probants auprès des jeunes patients anorexiques et de leur famille.

  3. Fluid resuscitation in acute pancreatitis

    PubMed Central

    Aggarwal, Aakash; Manrai, Manish; Kochhar, Rakesh

    2014-01-01

    Acute pancreatitis remains a clinical challenge, despite an exponential increase in our knowledge of its complex pathophysiological changes. Early fluid therapy is the cornerstone of treatment and is universally recommended; however, there is a lack of consensus regarding the type, rate, amount and end points of fluid replacement. Further confusion is added with the newer studies reporting better results with controlled fluid therapy. This review focuses on the pathophysiology of fluid depletion in acute pancreatitis, as well as the rationale for fluid replacement, the type, optimal amount, rate of infusion and monitoring of such patients. The basic goal of fluid epletion should be to prevent or minimize the systemic response to inflammatory markers. For this review, various studies and reviews were critically evaluated, along with authors’ recommendations, for predicted severe or severe pancreatitis based on the available evidence. PMID:25561779

  4. Squirming through shear thinning fluids

    NASA Astrophysics Data System (ADS)

    Datt, Charu; Zhu, Lailai; Elfring, Gwynn J.; Pak, On Shun

    2015-11-01

    Many microorganisms find themselves surrounded by fluids which are non-Newtonian in nature; human spermatozoa in female reproductive tract and motile bacteria in mucosa of animals are common examples. These biological fluids can display shear-thinning rheology whose effects on the locomotion of microorganisms remain largely unexplored. Here we study the self-propulsion of a squirmer in shear-thinning fluids described by the Carreau-Yasuda model. The squirmer undergoes surface distortions and utilizes apparent slip-velocities around its surface to swim through a fluid medium. In this talk, we will discuss how the nonlinear rheological properties of a shear-thinning fluid affect the propulsion of a swimmer compared with swimming in Newtonian fluids.

  5. Pump for delivering heated fluids

    NASA Technical Reports Server (NTRS)

    Sabelman, E. E. (Inventor)

    1973-01-01

    A thermomechanical pump particularly suited for use in pumping a warming fluid obtained from an RTG (Radioisotope Thermal Generator) through science and flight instrumentation aboard operative spacecraft is described. The invention is characterized by a pair of operatively related cylinders, each including a reciprocating piston head dividing the cylinder into a pressure chamber confining therein a vaporizable fluid, and a pumping chamber for propelling the warming fluid, and a fluid delivery circuit for alternately delivering the warming fluid from the RTG through the pressure chamber of one cylinder to the pumping chamber of the other cylinder, whereby the vaporizable fluid within the pair of pressure chambers alternately is vaporized and condensed for driving the associated pistons in pumping and intake strokes.

  6. Apparatus for Pumping a Fluid

    NASA Technical Reports Server (NTRS)

    van Boeyen, Roger W. (Inventor); Reeh, Jonathan A. (Inventor); Kesmez, Mehmet (Inventor); Heselmeyer, Eric A. (Inventor); Parkey, Jeffrey S. (Inventor)

    2016-01-01

    An electrochemically actuated pump and an electrochemical actuator for use with a pump. The pump includes one of various stroke volume multiplier configurations with the pressure of a pumping fluid assisting actuation of a driving fluid bellows. The electrochemical actuator has at least one electrode fluidically coupled to the driving fluid chamber of the first pump housing and at least one electrode fluidically coupled to the driving fluid chamber of the second pump housing. Accordingly, the electrochemical actuator selectively pressurizes hydrogen gas within a driving fluid chamber. The actuator may include a membrane electrode assembly including an ion exchange membrane with first and second catalyzed electrodes in contact with opposing sides of the membrane, and first and second hydrogen gas chambers in fluid communication with the first and second electrodes, respectively. A controller may reverse the polarity of a voltage source electrically coupled to the current collectors.

  7. Complex Fluids and Hydraulic Fracturing.

    PubMed

    Barbati, Alexander C; Desroches, Jean; Robisson, Agathe; McKinley, Gareth H

    2016-06-07

    Nearly 70 years old, hydraulic fracturing is a core technique for stimulating hydrocarbon production in a majority of oil and gas reservoirs. Complex fluids are implemented in nearly every step of the fracturing process, most significantly to generate and sustain fractures and transport and distribute proppant particles during and following fluid injection. An extremely wide range of complex fluids are used: naturally occurring polysaccharide and synthetic polymer solutions, aqueous physical and chemical gels, organic gels, micellar surfactant solutions, emulsions, and foams. These fluids are loaded over a wide range of concentrations with particles of varying sizes and aspect ratios and are subjected to extreme mechanical and environmental conditions. We describe the settings of hydraulic fracturing (framed by geology), fracturing mechanics and physics, and the critical role that non-Newtonian fluid dynamics and complex fluids play in the hydraulic fracturing process.

  8. [Fluid therapy in acute pancreatitis].

    PubMed

    de-Madaria, Enrique

    2013-12-01

    Severe acute pancreatitis (AP) is associated with an increased need for fluids due to fluid sequestration and, in the most severe cases, with decreased peripheral vascular tone. For several decades, clinical practice guidelines have recommended aggressive fluid therapy to improve the prognosis of AP. This recommendation is based on theoretical models, animal studies, and retrospective studies in humans. Recent studies suggest that aggressive fluid administration in all patients with AP could have a neutral or harmful effect. Fluid therapy based on Ringer's lactate could improve the course of the disease, although further studies are needed to confirm this possibility. Most patients with AP do not require invasive monitoring of hemodynamic parameters to guide fluid therapy administration. Moreover, the ability of these parameters to improve prognosis has not been demonstrated.

  9. Simulation de l'accretion de glace sur un obstacle bidimensionnel par la methode des bissectrices et par la modelisation des ruisselets et des gouttes de surface

    NASA Astrophysics Data System (ADS)

    Fortin, Guy

    Le LIMA (Laboratoire International des Materiaux Antigivre) en collaboration avec le CIRA (Italian Aerospace Research Centre) a developpe un logiciel simulant l'accretion de la glace en regimes sec et humide sur un objet bidimensionnel fixe. L'approche utilisee s'appuie sur les travaux de Lozowski pour les bilans energetiques, sur une etude du comportement du film d'eau, des ruisselets et des gouttes de surface pour le calcul des rugosites et des masses d'eau residuelle, ainsi que sur une methode de bissectrice pour l'evolution de la surface de glace. La contribution du CIRA a ete de fournir le logiciel pour le calcul des ecoulements et de la captation. Le bilan energetique base sur la conservation de l'energie est la sommation de la chaleur latente de fusion, d'evaporation et de sublimation, du rechauffement adiabatique et cinetique, et des pertes de chaleur par convection et conduction, ainsi que de l'evolution thermodynamique de l'eau de son etat initial a son etat final. La densite de la glace, qui a un impact important sur la simulation, est calculee a partir d'une correlation empirique developpee avec les cylindres tournants. En se basant sur les travaux de Al-Khalil et Hansman, le comportement des gouttes en regimes sec et humide a ete decrit analytiquement, ce qui a mene a determiner la hauteur maximale que peuvent atteindre les gouttes avant mouvement. Cette hauteur, appelee hauteur de mouvement, permet de determiner l'etat de l'eau sur la surface (film, ruisselets ou gouttes), ainsi que la hauteur des rugosites lorsque l'eau existe sous forme de gouttes ou de ruisselets. La hauteur de mouvement est determinee par l'equilibre entre les forces de cisaillement, induites par les effets aerodynamiques et gravitationnels evalues pour une goutte non deformee, et la force de cisaillement, induite par la tension de surface et la deformation de la goutte. Elle a ete validee en laboratoire et la precision obtenue pour la partie aerodynamique et gravitationnelle est

  10. Modelisation microstructurale en fatigue/fluage a froid des alliages de titane quasi alpha par le modele des automates cellulaires

    NASA Astrophysics Data System (ADS)

    Boutana, Mohammed Nabil

    Les proprietes d'emploi des alliages de titane sont extremement dependantes a certains aspects des microstructures developpees lors de leur elaboration. Ces microstructures peuvent etre fortement heterogenes du point de vue de leur orientation cristallographique et de leur repartition spatiale. Leurs influences sur le comportement du materiau et son endommagement precoce sont des questions qui sont actuellement soulevees. Dans le present projet de doctorat on chercher a repondre a cette question mais aussi de presenter des solutions tangibles quant a l'utilisation securitaire de ces alliages. Un nouveau modele appele automate cellulaire a ete developpe pour simuler le comportement mecanique des alliages de titane en fatigue-fluage a froid. Ces modeles ont permet de mieux comprendre la correlation entre la microstructure et le comportement mecanique du materiau et surtout une analyse detaillee du comportement local du materiau. Mots-cles: Automate cellulaire, fatigue/fluage, alliage de titane, inclusion d'Eshelby, modelisation

  11. Fluids in crustal deformation: Fluid flow, fluid-rock interactions, rheology, melting and resources

    NASA Astrophysics Data System (ADS)

    Lacombe, Olivier; Rolland, Yann

    2016-11-01

    Fluids exert a first-order control on the structural, petrological and rheological evolution of the continental crust. Fluids interact with rocks from the earliest stages of sedimentation and diagenesis in basins until these rocks are deformed and/or buried and metamorphosed in orogens, then possibly exhumed. Fluid-rock interactions lead to the evolution of rock physical properties and rock strength. Fractures and faults are preferred pathways for fluids, and in turn physical and chemical interactions between fluid flow and tectonic structures, such as fault zones, strongly influence the mechanical behaviour of the crust at different space and time scales. Fluid (over)pressure is associated with a variety of geological phenomena, such as seismic cycle in various P-T conditions, hydrofracturing (including formation of sub-horizontal, bedding-parallel veins), fault (re)activation or gravitational sliding of rocks, among others. Fluid (over)pressure is a governing factor for the evolution of permeability and porosity of rocks and controls the generation, maturation and migration of economic fluids like hydrocarbons or ore forming hydrothermal fluids, and is therefore a key parameter in reservoir studies and basin modeling. Fluids may also help the crust partially melt, and in turn the resulting melt may dramatically change the rheology of the crust.

  12. Ultrasonic Fluid Quality Sensor System

    DOEpatents

    Gomm, Tyler J.; Kraft, Nancy C.; Phelps, Larry D.; Taylor, Steven C.

    2003-10-21

    A system for determining the composition of a multiple-component fluid and for determining linear flow comprising at least one sing-around circuit that determines the velocity of a signal in the multiple-component fluid and that is correlatable to a database for the multiple-component fluid. A system for determining flow uses two of the inventive circuits, one of which is set at an angle that is not perpendicular to the direction of flow.

  13. The Fluids and Combustion Facility

    NASA Technical Reports Server (NTRS)

    Kundu, Sampa

    2004-01-01

    Microgravity is an environment with very weak gravitational effects. The Fluids and Combustion Facility (FCF) on the International Space Station (ISS) will support the study of fluid physics and combustion science in a long-duration microgravity environment. The Fluid Combustion Facility's design will permit both independent and remote control operations from the Telescience Support Center. The crew of the International Space Station will continue to insert and remove the experiment module, store and reload removable data storage and media data tapes, and reconfigure diagnostics on either side of the optics benches. Upon completion of the Fluids Combustion Facility, about ten experiments will be conducted within a ten-year period. Several different areas of fluid physics will be studied in the Fluids Combustion Facility. These areas include complex fluids, interfacial phenomena, dynamics and instabilities, and multiphase flows and phase change. Recently, emphasis has been placed in areas that relate directly to NASA missions including life support, power, propulsion, and thermal control systems. By 2006 or 2007, a Fluids Integrated Rack (FIR) and a Combustion Integrated Rack (CIR) will be installed inside the International Space Station. The Fluids Integrated Rack will contain all the hardware and software necessary to perform experiments in fluid physics. A wide range of experiments that meet the requirements of the international space station, including research from other specialties, will be considered. Experiments will be contained in subsystems such as the international standard payload rack, the active rack isolation system, the optics bench, environmental subsystem, electrical power control unit, the gas interface subsystem, and the command and data management subsystem. In conclusion, the Fluids and Combustion Facility will allow researchers to study fluid physics and combustion science in a long-duration microgravity environment. Additional information is

  14. Geophysical Fluid Flow Cell Simulation

    NASA Technical Reports Server (NTRS)

    1998-01-01

    Computer simulation of atmospheric flow corresponds well to imges taken during the second Geophysical Fluid Flow Cell (BFFC) mission. The top shows a view from the pole, while the bottom shows a view from the equator. Red corresponds to hot fluid rising while blue shows cold fluid falling. This simulation was developed by Anil Deane of the University of Maryland, College Park and Paul Fischer of Argorne National Laboratory. Credit: NASA/Goddard Space Flight Center

  15. Ultrasonic fluid quality sensor system

    DOEpatents

    Gomm, Tyler J.; Kraft, Nancy C.; Phelps, Larry D.; Taylor, Steven C.

    2002-10-08

    A system for determining the composition of a multiple-component fluid and for determining linear flow comprising at least one sing-around circuit that determines the velocity of a signal in the multiple-component fluid and that is correlatable to a database for the multiple-component fluid. A system for determining flow uses two of the inventive circuits, one of which is set at an angle that is not perpendicular to the direction of flow.

  16. DES Prediction of Cavitation Erosion and Its Validation for a Ship Scale Propeller

    NASA Astrophysics Data System (ADS)

    Ponkratov, Dmitriy, Dr

    2015-12-01

    Lloyd's Register Technical Investigation Department (LR TID) have developed numerical functions for the prediction of cavitation erosion aggressiveness within Computational Fluid Dynamics (CFD) simulations. These functions were previously validated for a model scale hydrofoil and ship scale rudder [1]. For the current study the functions were applied to a cargo ship's full scale propeller, on which the severe cavitation erosion was reported. The performed Detach Eddy Simulation (DES) required a fine computational mesh (approximately 22 million cells), together with a very small time step (2.0E-4 s). As the cavitation for this type of vessel is primarily caused by a highly non-uniform wake, the hull was also included in the simulation. The applied method under predicted the cavitation extent and did not fully resolve the tip vortex; however, the areas of cavitation collapse were captured successfully. Consequently, the developed functions showed a very good prediction of erosion areas, as confirmed by comparison with underwater propeller inspection results.

  17. Fluid Therapy in Lung Disease.

    PubMed

    Rozanski, Elizabeth; Lynch, Alex

    2017-03-01

    Fluid therapy is the cornerstone of supportive care in veterinary medicine. In dogs and cats with preexisting confirmed or suspected pulmonary disease, concerns may exist that the fluid therapy may impair gas exchange, either through increases in hydrostatic pressures or extravasation. Colloidal therapy is more likely to magnify lung injury compared with isotonic crystalloids. Radiographic evidence of fluid overload is a late-stage finding, whereas point-of-care ultrasound may provide earlier information that can also be assessed periodically at the patient side. Cases should be evaluated individually, but generally a conservative fluid therapy plan is preferred with close monitoring of its tolerance.

  18. Fluid relief and check valve

    DOEpatents

    Blaedel, K.L.; Lord, S.C.; Murray, I.

    1986-07-17

    A passive fluid pressure relief and check valve allows the relief pressure to be slaved to a reference pressure independently of the exhaust pressure. The pressure relief valve is embodied by a submerged vent line in a sealing fluid, the relief pressure being a function of the submerged depth. A check valve is embodied by a vertical column of fluid (the maximum back pressure being a function of the height of the column of fluid). The pressure is vented into an exhaust system which keeps the exhaust out of the area providing the reference pressure.

  19. Fluid Merging Viscosity Measurement (FMVM)

    NASA Technical Reports Server (NTRS)

    2004-01-01

    Astronaut Mike Fincke places droplets of honey onto the strings for the Fluid Merging Viscosity Measurement (FMVM) investigation onboard the International Space Station (ISS). The FMVM experiment measures the time it takes for two individual highly viscous fluid droplets to coalesce or merge into one droplet. Different fluids and droplet size combinations were tested in the series of experiments. By using the microgravity environment, researchers can measure the viscosity or 'thickness' of fluids without the influence of containers and gravity using this new technique. Understanding viscosity could help scientists understand industrially important materials such as paints, emulsions, polymer melts and even foams used to produce pharmaceutical, food, and cosmetic products.

  20. Fluid Resuscitation in Severe Sepsis.

    PubMed

    Loflin, Rob; Winters, Michael E

    2017-02-01

    Since its original description in 1832, fluid resuscitation has become the cornerstone of early and aggressive treatment of severe sepsis and septic shock. However, questions remain about optimal fluid composition, dose, and rate of administration for critically ill patients. This article reviews pertinent physiology of the circulatory system, pathogenesis of septic shock, and phases of sepsis resuscitation, and then focuses on the type, rate, and amount of fluid administration for severe sepsis and septic shock, so providers can choose the right fluid, for the right patient, at the right time.

  1. Respiratory fluid mechanics

    NASA Astrophysics Data System (ADS)

    Grotberg, James B.

    2011-02-01

    This article covers several aspects of respiratory fluid mechanics that have been actively investigated by our group over the years. For the most part, the topics involve two-phase flows in the respiratory system with applications to normal and diseased lungs, as well as therapeutic interventions. Specifically, the topics include liquid plug flow in airways and at airway bifurcations as it relates to surfactant, drug, gene, or stem cell delivery into the lung; liquid plug rupture and its damaging effects on underlying airway epithelial cells as well as a source of crackling sounds in the lung; airway closure from "capillary-elastic instabilities," as well as nonlinear stabilization from oscillatory core flow which we call the "oscillating butter knife;" liquid film, and surfactant dynamics in an oscillating alveolus and the steady streaming, and surfactant spreading on thin viscous films including our discovery of the Grotberg-Borgas-Gaver shock.

  2. Geophysical Fluid Dynamics

    NASA Astrophysics Data System (ADS)

    Busse, F. H.

    In the past 8 years, since Pedlosky's book was first published, it has found a well established place in the literature of dynamical meteorology and physical oceanography. Geophysicists less familiar with these fields may need to be reminded that the subject of geophysical fluid dynamics, in the narrow definition used in the title of the book, refers to the theory of the large-scale motions of the atmosphere and the oceans. Topics such as thermal convection in the atmosphere or in Earth's mantle and core are not treated in this book, and the reader will search in vain for a discussion of atmospheric or oceanic tides. The theory of quasi-geostrophic flow is described comprehensively, however, and its major applications to problems of atmospheric and oceanic circulations are considered in detail.

  3. Synovial fluid analysis.

    PubMed

    Brannan, Scott R; Jerrard, David A

    2006-04-01

    AsA prompt and accurate diagnosis of a painful, swollen joint is imperative, primarily in the case of a septic joint, as delayed therapy may result in progression of disease or permanent loss of function. Procurement and analysis of synovial fluid (SF) are paramount in helping the clinician to determine a patient's clinical condition and further course of treatment. Measurement of white blood cell (WBC) counts, crystal analysis by polarized microscopy, and microbiologic studies including Gram stain and culture are the SF parameters that are collectively most important in the ultimate determination by a clinician of the presence or absence of an infectious or inflammatory joint. It is important for the clinician to understand and recognize the limitations of various SF parameters to minimize under-treating patients with potentially serious joint pathology.

  4. Respiratory fluid mechanics

    PubMed Central

    Grotberg, James B.

    2011-01-01

    This article covers several aspects of respiratory fluid mechanics that have been actively investigated by our group over the years. For the most part, the topics involve two-phase flows in the respiratory system with applications to normal and diseased lungs, as well as therapeutic interventions. Specifically, the topics include liquid plug flow in airways and at airway bifurcations as it relates to surfactant, drug, gene, or stem cell delivery into the lung; liquid plug rupture and its damaging effects on underlying airway epithelial cells as well as a source of crackling sounds in the lung; airway closure from “capillary-elastic instabilities,” as well as nonlinear stabilization from oscillatory core flow which we call the “oscillating butter knife;” liquid film, and surfactant dynamics in an oscillating alveolus and the steady streaming, and surfactant spreading on thin viscous films including our discovery of the Grotberg–Borgas–Gaver shock. PMID:21403768

  5. Fluid infusion system

    NASA Technical Reports Server (NTRS)

    Hammond, J. C.

    1975-01-01

    Development of a fluid infusion system was undertaken in response to a need for an intravenous infusion device operable under conditions of zero-g. The initial design approach, pursued in the construction of the first breadboard instrument, was to regulate the pressure of the motive gas to produce a similar regulated pressure in the infusion liquid. This scheme was not workable because of the varying bag contact area, and a major design iteration was made. A floating sensor plate in the center of the bag pressure plate was made to operate a pressure regulator built into the bellows assembly, effectively making liquid pressure the directly controlled variable. Other design changes were made as experience was gained with the breadboard. Extensive performance tests were conducted on both the breadboard and the prototype device; accurately regulated flows from 6 m1/min to 100 m1/min were achieved. All system functions were shown to operate satisfactorily.

  6. Fluid Flow of Vitrectomy

    NASA Astrophysics Data System (ADS)

    Sharif-Kashani, Pooria; Juan, Tingting; Hubschman, Jean-Pierre; Eldredge, Jeff D.; Pirouz Kavehpour, H.

    2011-11-01

    Vitrectomy is a microsurgical technique to remove the vitreous gel from the vitreous cavity. Due to the viscoelastic nature of the vitreous gel, its complex fluidic behavior during vitrectomy affects the outcome of the procedure. Therefore, the knowledge of such behavior is essential for better designing the vitrectomy devices, such as vitreous cutters, and tuning the system settings such as port and shaft diameters, infusion, vacuum, and cutting rate. We studied the viscoelastic properties of porcine vitreous humor using a stressed-control shear rheometer and obtained its relaxation time, retardation time, and shear-zero viscosity. We performed a computational study of the flow in a vitreous cutter using the viscoelastic parameters obtained from the rheology experiments. We found significant differences between the modeled vitreous gel and a Newtonian surrogate fluid in the flow behavior and performance of the vitreous cutter. Our results will help in understanding of the vitreous behavior during vitrectomy and providing guidelines for new vitreous cutter design.

  7. FLUID CONTACTOR APPARATUS

    DOEpatents

    Spence, R.; Streeton, R.J.W.

    1956-04-17

    The fluid contactor apparatus comprises a cylindrical column mounted co- axially and adapted to rotate within a cylindrical vessel, for the purpose of extracting a solute from am aqueous solution by means of an organic solvent. The column is particularly designed to control the vortex pattern so as to reduce the height of the vortices while, at the same time, the width of the annular radius in the radial direction between the vessel and column is less than half the radius of the column. A plurality of thin annular fins are spaced apart along the rotor approximately twice the radial dimension of the column such that two contrarotating substantially circular vortices are contained within each pair of fins as the column is rotated.

  8. Fluid quantity gaging

    NASA Technical Reports Server (NTRS)

    Mord, Allan J.; Snyder, Howard A.; Kilpatrick, Kathleen A.; Hermanson, Lynn A.; Hopkins, Richard A.; Vangundy, Donald A.

    1988-01-01

    A system for measuring the mass of liquid in a tank on orbit with 1 percent accuracy was developed and demonstrated. An extensive tradeoff identified adiabatic compression as the only gaging technique that is independent of gravity or its orientation, and of the size and distribution of bubbles in the tank. This technique is applicable to all Earth-storable and cryogenic liquids of interest for Space Station use, except superfluid helium, and can be applied to tanks of any size, shape, or internal structure. Accuracy of 0.2 percent was demonstrated in the laboratory, and a detailed analytical model was developed and verified by testing. A flight system architecture is presented that allows meeting the needs of a broad range of space fluid systems without custom development for each user.

  9. Respiratory fluid mechanics.

    PubMed

    Grotberg, James B

    2011-02-01

    This article covers several aspects of respiratory fluid mechanics that have been actively investigated by our group over the years. For the most part, the topics involve two-phase flows in the respiratory system with applications to normal and diseased lungs, as well as therapeutic interventions. Specifically, the topics include liquid plug flow in airways and at airway bifurcations as it relates to surfactant, drug, gene, or stem cell delivery into the lung; liquid plug rupture and its damaging effects on underlying airway epithelial cells as well as a source of crackling sounds in the lung; airway closure from "capillary-elastic instabilities," as well as nonlinear stabilization from oscillatory core flow which we call the "oscillating butter knife;" liquid film, and surfactant dynamics in an oscillating alveolus and the steady streaming, and surfactant spreading on thin viscous films including our discovery of the Grotberg-Borgas-Gaver shock.

  10. Fluid Mechanics of Taste

    NASA Astrophysics Data System (ADS)

    Noel, Alexis; Bhatia, Nitesh; Carter, Taren; Hu, David

    2015-11-01

    Saliva plays a key role in digestion, speech and tactile sensation. Lack of saliva, also known as dry mouth syndrome, increases risk of tooth decay and alters sense of taste; nearly 10% of the general population suffer from this syndrome. In this experimental study, we investigate the spreading of water drops on wet and dry tongues of pigs and cows. We find that drops spread faster on a wet tongue than a dry tongue. We rationalize the spreading rate by consideration of the tongue microstructure, such as as papillae, in promoting wicking. By investigating how tongue microstructure affects spreading of fluids, we may begin to how understand taste receptors are activated by eating and drinking.

  11. Fluid dynamics in developmental biology: moving fluids that shape ontogeny

    PubMed Central

    Cartwright, Julyan H.E.; Piro, Oreste; Tuval, Idan

    2009-01-01

    Human conception, indeed fertilization in general, takes place in a fluid, but what role does fluid dynamics have during the subsequent development of an organism? It is becoming increasingly clear that the number of genes in the genome of a typical organism is not sufficient to specify the minutiae of all features of its ontogeny. Instead, genetics often acts as a choreographer, guiding development but leaving some aspects to be controlled by physical and chemical means. Fluids are ubiquitous in biological systems, so it is not surprising that fluid dynamics should play an important role in the physical and chemical processes shaping ontogeny. However, only in a few cases have the strands been teased apart to see exactly how fluid forces operate to guide development. Here, we review instances in which the hand of fluid dynamics in developmental biology is acknowledged, both in human development and within a wider biological context, together with some in which fluid dynamics is notable but whose workings have yet to be understood, and we provide a fluid dynamicist’s perspective on possible avenues for future research. PMID:19794816

  12. A FLUID SORBENT RECYCLING DEVICE FOR INDUSTRIAL FLUID USERS

    EPA Science Inventory

    A roller compression Extractor® that extracts fluids from reusable sorbent pads was evaluated as a method of waste reduction. The extraction device, evaluated for industrial fluid users in New Jersey, was found to be effective in recycling unpleated sorbent pads, especially ...

  13. Salinity of oceanic hydrothermal fluids: a fluid inclusion study

    NASA Astrophysics Data System (ADS)

    Nehlig, Pierre

    1991-03-01

    An extensive microthermometric study of quartz, epidote, plagioclase, anhydrite and sphalerite-hosted fluid inclusions from ophiolitic [Semail (Oman) and Trinity (California) ophiolites] and oceanic (East Pacific Rise hydrothermal vents, Gorringe Bank, ODP Leg 111 Hole 504B) crust has been carried out in order to constrain a model accounting for wide salinity variations measured in the oceanic hydrothermal fluids. Recorded salinities in fluid inclusions vary between 0.3 and 52 wt% NaCl eq. However, more than 60% of the mean (± standard deviation) salinities of the samples are within the range 3.2 ± 0.3wt% NaCl eq (= microthermometric error) and the mean salinity of all fluid inclusions (without the brines) is 4.0 wt% NaCl eq with a standard deviation of 1.6 wt% NaCl eq. Whereas most samples display slightly higher salinities than seawater, several samples exhibit very high salinities (more than two times that of seawater). These high salinities are restricted to the plagiogranites (Semail and Trinity ophiolites) which mark the top of the fossil magma chamber, in the transition zone between the plutonic sequence and the sheeted dyke complex. The fluid inclusion population studied in the plagiogranites is characterized by the occurrence of four major fluid inclusion families: (1) low- to medium-salinity Liquid/Vapor fluid inclusions which homogenize into the liquid phase; (2) low-salinity Liquid/Vapor fluid inclusions with pseudocritical homogenization; (3) low- to medium-salinity Liquid/Vapor fluid inclusions which homogenize into the vapor phase; and (4) high-salinity Liquid/Vapor/Halite fluid inclusions which homogenize into the liquid phase by halite dissolution and exhibit salinities as high as 52 wt% NaCl eq. These fluid inclusion families are interpreted as resulting from phase separation occurring in hydrothermal or magmatic fluids within the transition zone between the hydrothermal system and the magma chamber at temperatures higher than 500°C. Very low

  14. Fluid absorption solar energy receiver

    NASA Technical Reports Server (NTRS)

    Bair, Edward J.

    1993-01-01

    A conventional solar dynamic system transmits solar energy to the flowing fluid of a thermodynamic cycle through structures which contain the gas and thermal energy storage material. Such a heat transfer mechanism dictates that the structure operate at a higher temperature than the fluid. This investigation reports on a fluid absorption receiver where only a part of the solar energy is transmitted to the structure. The other part is absorbed directly by the fluid. By proportioning these two heat transfer paths the energy to the structure can preheat the fluid, while the energy absorbed directly by the fluid raises the fluid to its final working temperature. The surface temperatures need not exceed the output temperature of the fluid. This makes the output temperature of the gas the maximum temperature in the system. The gas can have local maximum temperatures higher than the output working temperature. However local high temperatures are quickly equilibrated, and since the gas does not emit radiation, local high temperatures do not result in a radiative heat loss. Thermal radiation, thermal conductivity, and heat exchange with the gas all help equilibrate the surface temperature.

  15. An Introduction to Fluid Dynamics

    NASA Astrophysics Data System (ADS)

    Batchelor, G. K.

    2000-02-01

    First published in 1967, Professor Batchelor's classic work is still one of the foremost texts on fluid dynamics. His careful presentation of the underlying theories of fluids is still timely and applicable, even in these days of almost limitless computer power. This reissue ensures that a new generation of graduate students experiences the elegance of Professor Batchelor's writing.

  16. Fluid jet electric discharge source

    DOEpatents

    Bender, Howard A.

    2006-04-25

    A fluid jet or filament source and a pair of coaxial high voltage electrodes, in combination, comprise an electrical discharge system to produce radiation and, in particular, EUV radiation. The fluid jet source is composed of at least two serially connected reservoirs, a first reservoir into which a fluid, that can be either a liquid or a gas, can be fed at some pressure higher than atmospheric and a second reservoir maintained at a lower pressure than the first. The fluid is allowed to expand through an aperture into a high vacuum region between a pair of coaxial electrodes. This second expansion produces a narrow well-directed fluid jet whose size is dependent on the size and configuration of the apertures and the pressure used in the reservoir. At some time during the flow of the fluid filament, a high voltage pulse is applied to the electrodes to excite the fluid to form a plasma which provides the desired radiation; the wavelength of the radiation being determined by the composition of the fluid.

  17. Applied Fluid Mechanics. Lecture Notes.

    ERIC Educational Resources Information Center

    Gregg, Newton D.

    This set of lecture notes is used as a supplemental text for the teaching of fluid dynamics, as one component of a thermodynamics course for engineering technologists. The major text for the course covered basic fluids concepts such as pressure, mass flow, and specific weight. The objective of this document was to present additional fluids…

  18. Emerging string of fluid pearls

    NASA Astrophysics Data System (ADS)

    Kim, Seong Jin; Jang, Minsu; Um, Soong Ho; Jung, Sunghwan

    2016-09-01

    This paper is associated with a poster winner of a 2015 APS/DFD Milton van Dyke Award for work presented at the DFD Gallery of Fluid Motion. The original poster is available from the Gallery of Fluid Motion, http://dx.doi.org/10.1103/APS.DFD.2015.GFM.P0048

  19. FLUID PURIFIER AND SEALING VALVE

    DOEpatents

    Swanton, W.F.

    1962-04-24

    An improved cold trap designed to condense vapors and collect foreign particles in a flowing fluid is described. In the arrangement, a valve is provided to prevent flow reversal in case of pump failure and to act as a sealing valve. Provision is made for reducing the temperature of the fluid being processed, including a pre-cooling stage. (AEC)

  20. Magnetic Fluids--Part 2.

    ERIC Educational Resources Information Center

    Hoon, S. B.; Tanner, B. K.

    1985-01-01

    Continues a discussion of magnetic fluids by providing background information on and procedures for conducting several demonstrations. Indicates that, with a little patience and ingenuity, only modest magnetic fields and about 20 ml of low-viscosity, commercial magnetite-water-based magnetic fluid are required. (JN)

  1. Annual Program Management Report 1989: Des Moines Recreational River and Greenbelt, Des Moines River, Iowa

    DTIC Science & Technology

    1989-10-01

    Rock Island District EXECUTIVE SUMMARY The General Design Memorandum (GDM) and Programmatic Environmental Impact Statement for the Des Moines...River and Greenbelt Programmatic Environmental Impact Statement. 40 Recommended for Preoaration of Feature Design Memoranda Bellville Overlook Sever...of the dam and lake is a wasteful expenditure of public money and would have extreme adverse impact on the environment in the area. The area is now

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

    NASA Astrophysics Data System (ADS)

    Dolez, Patricia

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

  3. Des agents de santé communautaires pour la promotion de la santé des pasteurs nomades au Mali.

    PubMed

    Ag Ahmed, Mohamed Ali

    2016-12-01

    Au Mali, les nomades (des Maures, Touaregs et Peulhs) représentent environ 1,25 million de personnes. Les services de santé leur sont peu accessibles en raison de leur mobilité, liée à leur activité d'élevage. La question que se posent plusieurs intervenants en santé publique des pays où vivent ces nomades est de savoir comment améliorer leur santé. Dans ce commentaire, après un bref exposé des problèmes liés à l'accès aux services de santé, nous proposons une approche innovante et holistique de la santé, qui soutient que des agents de santé communautaires (ASC) pourraient contribuer à améliorer la santé des nomades en offrant conjointement des services de santé aux nomades et à leurs animaux (le concept « One Health » [d'Une Seule Santé]). Des pistes de réflexion sont dégagées, quant aux principaux défis pour leur efficacité et durabilité, qui sont la conception et gestion du programme, leur soutien par les communautés et leur intégration aux services de santé publique et vétérinaire.

  4. Effective perfect fluids in cosmology

    SciTech Connect

    Ballesteros, Guillermo; Bellazzini, Brando E-mail: brando.bellazzini@pd.infn.it

    2013-04-01

    We describe the cosmological dynamics of perfect fluids within the framework of effective field theories. The effective action is a derivative expansion whose terms are selected by the symmetry requirements on the relevant long-distance degrees of freedom, which are identified with comoving coordinates. The perfect fluid is defined by requiring invariance of the action under internal volume-preserving diffeomorphisms and general covariance. At lowest order in derivatives, the dynamics is encoded in a single function of the entropy density that characterizes the properties of the fluid, such as the equation of state and the speed of sound. This framework allows a neat simultaneous description of fluid and metric perturbations. Longitudinal fluid perturbations are closely related to the adiabatic modes, while the transverse modes mix with vector metric perturbations as a consequence of vorticity conservation. This formalism features a large flexibility which can be of practical use for higher order perturbation theory and cosmological parameter estimation.

  5. Fluid Dynamics of Bottle Filling

    NASA Astrophysics Data System (ADS)

    McGough, Patrick; Gao, Haijing; Appathurai, Santosh; Basaran, Osman

    2011-11-01

    Filling of bottles is a widely practiced operation in a large number of industries. Well known examples include filling of ``large'' bottles with shampoos and cleaners in the household products and beauty care industries and filling of ``small'' bottles in the pharmaceutical industry. Some bottle filling operations have recently drawn much attention from the fluid mechanics community because of the occurrence of a multitude of complex flow regimes, transitions, and instabilities such as mounding and coiling that occur as a bottle is filled with a fluid. In this talk, we present a primarily computational study of the fluid dynamical challenges that can arise during the rapid filling of bottles. Given the diversity of fluids used in filling applications, we consider four representative classes of fluids that exhibit Newtonian, shear-thinning, viscoelastic, and yield-stress rheologies. The equations governing the dynamics of bottle filling are solved either in their full 3D but axisymmetric form or using the slender-jet approximation.

  6. Second Microgravity Fluid Physics Conference

    NASA Technical Reports Server (NTRS)

    1994-01-01

    The conference's purpose was to inform the fluid physics community of research opportunities in reduced-gravity fluid physics, present the status of the existing and planned reduced gravity fluid physics research programs, and inform participants of the upcoming NASA Research Announcement in this area. The plenary sessions provided an overview of the Microgravity Fluid Physics Program information on NASA's ground-based and space-based flight research facilities. An international forum offered participants an opportunity to hear from French, German, and Russian speakers about the microgravity research programs in their respective countries. Two keynote speakers provided broad technical overviews on multiphase flow and complex fluids research. Presenters briefed their peers on the scientific results of their ground-based and flight research. Fifty-eight of the sixty-two technical papers are included here.

  7. Optimisation des transferts de chaleur dans un systeme de stockage d'hydrogene a base d'alanate de sodium

    NASA Astrophysics Data System (ADS)

    Bhouri, Maha

    Le déploiement des applications de transport basées sur l'hydrogène comme source d'énergie est assujetti à l'identification d'une méthode efficace pour son stockage. En ce qui concerne la voie de stockage solide, les principaux inconvénients sont les faibles propriétés thermiques de l'hydrure, le long temps de chargement du réservoir et sa faible capacité gravimétrique. Dans ce cadre, l'alanate de sodium est choisi comme matériau de référence pour optimiser le fonctionnement d'un système de stockage d'un kilogramme d'hydrogène, en termes d'efficacité thermique et de capacités gravimétrique et volumétrique. Trois configurations ont été considérées en variant la disposition du lit d'hydrure et du fluide de refroidissement ainsi que le choix des échangeurs de chaleur et des structures permettant l'amélioration des propriétés thermiques de ce lit. Le modèle mathématique décrivant les transferts de chaleur et de masse au sein du lit d'hydrure a été résolu avec le logiciel commercial COMSOL Multiphysics® 3.5a. Les résultats numériques nous ont permis de déterminer l'interaction entre les propriétés géométriques des éléments d'échange de chaleur et le taux de stockage d'hydrogène ainsi que sa dépendance des conditions opérationnelles. L'efficacité thermique du système de stockage est déterminée en comparant le taux de stockage d'hydrogène calculé à celui issu du modèle de cinétique et validé avec les données expérimentales. Une fois que la quantité d'hydrogène stocké est optimisée, la contribution des éléments d'échange de chaleur au poids et au volume du réservoir et les capacités gravimétrique et volumétrique des configurations correspondantes sont déterminées et discutées en fonction des critères de sélection fixées par le DOE.

  8. Evaluation des connaissances des parents sur les bronchiolites aiguës

    PubMed Central

    Gueddari, Widad; Tazi, Abderrahmane; Ouardi, Amine; Nani, Samira; Zineddine, Abdelhadi

    2014-01-01

    Les infections respiratoires (IR) constituent la deuxième cause de mortalité infantile au Maroc, dû en partie à l'absence d'information et de sensibilisation. Le but de ce travail était d’évaluer les connaissances des parents sur la bronchiolite aiguë, infection respiratoire très fréquente. Nous avons réalisé une enquête basée sur un questionnaire, auprès de parents de nourrissons consultants pour toux, avec ou sans gêne respiratoire. 180 parents ont été inclus dans l’étude. Les parents pensaient que l'infection respiratoire était secondaire au climat froid (96%); seuls 4% ont évoqué une origine infectieuse. Aucun des parents ne savait que le lavage des mains était un moyen de prévention de la transmission. Les parents ont majoritairement répondu que la kinésithérapie respiratoire ne servait à rien (65%), et qu'elle était nocive (24.5%). Ce manque de connaissances fondamentales en matière d'IR et de bronchiolite en particulier, devrait inciter à entreprendre un programme de sensibilisation PMID:25328606

  9. Sécurité au-delà des mythes et des croyances

    ScienceCinema

    None

    2016-07-12

    Présentation orale en français, support visuel en français et en anglais. La pire des failles de sécurité est l'impression de sécurité. Le décalage entre la compréhension que l’on a des technologies utilisées, et leurs potentiels réels, ainsi que l'impact potentiellement négatif qu'elles peuvent avoir sur nos vies, n'est pas toujours compris, ou pris en compte par la plupart d'entre-nous. On se contente de nos perceptions pour ne pas avoir à se confronter à la réalité... Alors qu'en est-il vraiment ? En matière de sécurité qui de l'humain ou des technologies a le contrôle ?

  10. New Fluid Prevents Railway Ice

    NASA Technical Reports Server (NTRS)

    2001-01-01

    Through a licensing agreement between NASA's Ames Research Center and Midwest Industrial Supply, Inc. (MIS), two MIS products have been enhanced with NASA's anti-icing fluid technology. MIS offers the new fluid in two commercial products, the Zero Gravity(TM) Third Rail Anti-Icer/Deicer and the Ice Free Switch(R). Using NASA's fluid technology, these products form a protective-coating barrier that prevents the buildup of ice and snow. Applying the fluid to the railway components prior to ice or snowstorm works as an anti-icing fluid, remaining in place to melt precipitation as it hits the surface. It also functions as a deicing fluid. If applied to an already frozen switch or rail, it will quickly melt the ice, free the frozen parts, and then remain in place to prevent refreezing. Additional benefits include the ability to cling to vertical rail surfaces and resist the effects of rain and wind. With the Ice Free Switch, it takes only five minutes to treat the switch by spraying, brushing, or pouring on the product. Ice Free Switch requires as little as one gallon per switch whereas other deicing fluids require five to ten gallons of liquid to effectively melt ice. Zero Gravity serves the same anti-icing/deicing purposes but applies fluid to the third rail through a system that is easily installed onto mass transit cars. A tank of fluid and a dispensing system are placed underneath the train car and the fluid is applied as the train runs its route.

  11. Heating production fluids in a wellbore

    DOEpatents

    Orrego, Yamila; Jankowski, Todd A.

    2016-07-12

    A method for heating a production fluid in a wellbore. The method can include heating, using a packer fluid, a working fluid flowing through a first medium disposed in a first section of the wellbore, where the first medium transfers heat from the packer fluid to the working fluid. The method can also include circulating the working fluid into a second section of the wellbore through a second medium, where the second medium transfers heat from the working fluid to the production fluid. The method can further include returning the working fluid to the first section of the wellbore through the first medium.

  12. Retrograde fluids in granulites: Stable isotope evidence of fluid migration

    SciTech Connect

    Morrison, J. ); Valley, J.W. )

    1991-07-01

    Widespread retrograde alteration assemblages document the migration of mixed H{sub 2}O-CO{sub 2} fluids into granulite facies rocks in the Adirondack Mountains. Fluid migration is manifest by (1) veins and patchy intergrowths of chlorite {plus minus} sericite {plus minus} calcite, (2) small veins of calcite, many only identifiable by cathodoluminescence, and (3) high-density, CO{sub 2}-rich or mixed H{sub 2}O-CO{sub 2} fluid inclusions. The distinct and varied textural occurrences of the alteration minerals indicate that fluid-rock ratios were low and variable on a local scale. Stable isotope ratios of C, O, and S have been determined in retrograde minerals from samples of the Marcy anorthosite massif and adjacent granitic gneisses (charnockites). Retrograde calcite in the anorthosite has a relatively small range in both {delta}{sup 18}O{sub SMOW} and {delta}{sup 13}C{sub PDB} (8.6 to 14.9% and {minus}4.1 to 0.4%, respectively), probably indicating that the hydrothermal fluids that precipitated the calcite had exchanged with a variety of crustal lithologies including marbles and orthogneisses, and that calcite was precipitated over a relatively narrow temperature interval. Values of {delta}{sup 34}S{sub CDT} that range from 2.8 to 8.3% within the anorthosite can also be interpreted to reflect exchange between orthogneisses and metasediments. The recognition of retrograde fluid migration is particularly significant in granulite facies terranes because the controversy surrounding the origin of granulites arises in part from differing interpretations of fluid inclusion data, specifically, the timing of entrapment of high-density, CO{sub 2}-rich inclusions. Results indicate that retrograde fluid migration, which in some samples may leave only cryptic petrographic evidence, is a process capable of producing high-density, CO{sub 2}-rich fluid inclusions.

  13. Fluid shifts in weightlessness

    NASA Technical Reports Server (NTRS)

    Thornton, William E.; Moore, Thomas P.; Pool, Sam L.

    1987-01-01

    Studies of leg volumes in space by multiple girth measurements showed reductions of 1.9 l (12.8 percent of leg volume), with 1.1 l from the nondominant leg, on Skylab 4. On landing, 65 percent of postflight leg volume increase was complete at 1.5 h. Measurement of the dominant leg during the equivalent period on Shuttle showed a mean loss of 0.9 l which was 90-percent complete at 150 min. Postflight increases were 87-percent complete at 1.5 h postlanding. Mass measurements during and after Skylab 4 showed a loss of 2.5 kg over the first 4 d on orbit, with a gain of 2.7 kg over the first 4 d of recovery. These changes are assumed to be tissue fluids secondary to changes in hydrostatic pressures and are much greater than those seen in bed rest. Rate and magnitude of inflight and postflight changes have significant operational impact.

  14. Fluid sampling system

    DOEpatents

    Houck, E.D.

    1994-10-11

    An fluid sampling system allows sampling of radioactive liquid without spillage. A feed tank is connected to a liquid transfer jet powered by a pumping chamber pressurized by compressed air. The liquid is pumped upwardly into a sampling jet of a venturi design having a lumen with an inlet, an outlet, a constricted middle portion, and a port located above the constricted middle portion. The liquid is passed under pressure through the constricted portion causing its velocity to increase and its pressure to be decreased, thereby preventing liquid from escaping. A septum sealing the port can be pierced by a two pointed hollow needle leading into a sample bottle also sealed by a pierceable septum affixed to one end. The bottle is evacuated by flow through the sample jet, cyclic variation in the sampler jet pressure periodically leaves the evacuated bottle with lower pressure than that of the port, thus causing solution to pass into the bottle. The remaining solution in the system is returned to the feed tank via a holding tank. 4 figs.

  15. Fluid sampling system

    DOEpatents

    Houck, Edward D.

    1994-01-01

    An fluid sampling system allows sampling of radioactive liquid without spillage. A feed tank is connected to a liquid transfer jet powered by a pumping chamber pressurized by compressed air. The liquid is pumped upwardly into a sampling jet of a venturi design having a lumen with an inlet, an outlet, a constricted middle portion, and a port located above the constricted middle portion. The liquid is passed under pressure through the constricted portion causing its velocity to increase and its pressure to decreased, thereby preventing liquid from escaping. A septum sealing the port can be pierced by a two pointed hollow needle leading into a sample bottle also sealed by a pierceable septum affixed to one end. The bottle is evacuated by flow through the sample jet, cyclic variation in the sampler jet pressure periodically leaves the evacuated bottle with lower pressure than that of the port, thus causing solution to pass into the bottle. The remaining solution in the system is returned to the feed tank via a holding tank.

  16. Tracing Geothermal Fluids

    SciTech Connect

    Michael C. Adams; Greg Nash

    2004-03-01

    Geothermal water must be injected back into the reservoir after it has been used for power production. Injection is critical in maximizing the power production and lifetime of the reservoir. To use injectate effectively the direction and velocity of the injected water must be known or inferred. This information can be obtained by using chemical tracers to track the subsurface flow paths of the injected fluid. Tracers are chemical compounds that are added to the water as it is injected back into the reservoir. The hot production water is monitored for the presence of this tracer using the most sensitive analytic methods that are economically feasible. The amount and concentration pattern of the tracer revealed by this monitoring can be used to evaluate how effective the injection strategy is. However, the tracers must have properties that suite the environment that they will be used in. This requires careful consideration and testing of the tracer properties. In previous and parallel investigations we have developed tracers that are suitable from tracing liquid water. In this investigation, we developed tracers that can be used for steam and mixed water/steam environments. This work will improve the efficiency of injection management in geothermal fields, lowering the cost of energy production and increasing the power output of these systems.

  17. Fluid flow monitoring device

    DOEpatents

    McKay, Mark D.; Sweeney, Chad E.; Spangler, Jr., B. Samuel

    1993-01-01

    A flow meter and temperature measuring device comprising a tube with a body centered therein for restricting flow and a sleeve at the upper end of the tube to carry several channels formed longitudinally in the sleeve to the appropriate axial location where they penetrate the tube to allow pressure measurements and temperature measurements with thermocouples. The high pressure measurement is made using a channel penetrating the tube away from the body and the low pressure measurement is made at a location at the widest part of the body. An end plug seals the end of the device and holes at its upper end allow fluid to pass from the interior of the tube into a plenum. The channels are made by cutting grooves in the sleeve, the grooves widened at the surface of the sleeve and then a strip of sleeve material is welded to the grooves closing the channels. Preferably the sleeve is packed with powdered graphite before cutting the grooves and welding the strips.

  18. Computational fluid dynamic applications

    SciTech Connect

    Chang, S.-L.; Lottes, S. A.; Zhou, C. Q.

    2000-04-03

    The rapid advancement of computational capability including speed and memory size has prompted the wide use of computational fluid dynamics (CFD) codes to simulate complex flow systems. CFD simulations are used to study the operating problems encountered in system, to evaluate the impacts of operation/design parameters on the performance of a system, and to investigate novel design concepts. CFD codes are generally developed based on the conservation laws of mass, momentum, and energy that govern the characteristics of a flow. The governing equations are simplified and discretized for a selected computational grid system. Numerical methods are selected to simplify and calculate approximate flow properties. For turbulent, reacting, and multiphase flow systems the complex processes relating to these aspects of the flow, i.e., turbulent diffusion, combustion kinetics, interfacial drag and heat and mass transfer, etc., are described in mathematical models, based on a combination of fundamental physics and empirical data, that are incorporated into the code. CFD simulation has been applied to a large variety of practical and industrial scale flow systems.

  19. Viscous dark fluid universe

    SciTech Connect

    Hipolito-Ricaldi, W. S.; Velten, H. E. S.; Zimdahl, W.

    2010-09-15

    We investigate the cosmological perturbation dynamics for a universe consisting of pressureless baryonic matter and a viscous fluid, the latter representing a unified model of the dark sector. In the homogeneous and isotropic background the total energy density of this mixture behaves as a generalized Chaplygin gas. The perturbations of this energy density are intrinsically nonadiabatic and source relative entropy perturbations. The resulting baryonic matter power spectrum is shown to be compatible with the 2dFGRS and SDSS (DR7) data. A joint statistical analysis, using also Hubble-function and supernovae Ia data, shows that, different from other studies, there exists a maximum in the probability distribution for a negative present value q{sub 0{approx_equal}}-0.53 of the deceleration parameter. Moreover, while previous descriptions on the basis of generalized Chaplygin-gas models were incompatible with the matter power-spectrum data since they required a much too large amount of pressureless matter, the unified model presented here favors a matter content that is of the order of the baryonic matter abundance suggested by big-bang nucleosynthesis.

  20. Fluids and Combustion Facility: Fluids Integrated Rack Modal Model Correlation

    NASA Technical Reports Server (NTRS)

    McNelis, Mark E.; Suarez, Vicente J.; Sullivan, Timothy L.; Otten, Kim D.; Akers, James C.

    2005-01-01

    The Fluids Integrated Rack (FIR) is one of two racks in the Fluids and Combustion Facility on the International Space Station. The FIR is dedicated to the scientific investigation of space system fluids management supporting NASA s Exploration of Space Initiative. The FIR hardware was modal tested and FIR finite element model updated to satisfy the International Space Station model correlation criteria. The final cross-orthogonality results between the correlated model and test mode shapes was greater than 90 percent for all primary target modes.

  1. Modélisation des boucles d'immunisation magnétique des navires

    NASA Astrophysics Data System (ADS)

    Le Dorze, F.; Bongiraud, J. P.; Coulomb, J. L.; Meunier, G.; Brunotte, X.

    1998-02-01

    This paper presents the problem of the three-dimensional modeling of degaussing coils in ships with a finite elements method. We show that these current coils are so close to the ferromagnetic sheets of the ship that they require a local very fine mesh which would be unrealistic for the whole complex structure of a real ship. We propose an alternative to the expensive mesh refinement called "reduced scalar potential jump”. The idea is to previously solve the local problem by another method and to use the result in the whole FEM modelling. We present the method of implementation in the FEM software FLUX3D and comparative results on a simple geometry. Cet article présente le problème de la modélisation en trois dimensions des boucles d'immunisation des navires par la méthode des éléments finis. Nous montrons que ces boucles de courant sont si proches des tôles ferromagnétiques du navire que leur modélisation requiert un maillage localement très fin, ce qui est irréaliste pour la structure complexe d'un navire réel. Nous proposons une alternative à ce coûteux affinage du maillage, appelée "saut de potentiel réduit”. L'idée est de résoudre au préalable le problème local par une autre méthode que les éléments finis et d'utiliser le résultat dans la modélisation globale. Nous présentons la méthode utilisée pour l'implantation de cette technique dans le logiciel d'éléments finis FLUX3D, et des résultats comparatifs sur une géométrie simple.

  2. Formation et Evolution des Quasars et Contraintes cosmologiques

    NASA Astrophysics Data System (ADS)

    Hatziminaoglou, Evanthia

    2000-06-01

    Cette thèse porte sur l'étude de l'évolution des quasars. Elle en aborde certains aspects théoriques et observationnels, ainsi que la construction des grands échantillons de quasars dans le but à long terme de combiner le tout dans un test cosmologique géométrique pour déterminer les valeurs des paramètres cosmologiques Omega et Lambda. Les paramètres cosmologiques Omegaspan>et Lambdaspan>décrivent la géométrie globale de l'Univers. En faisant des hypothèses raisonnables sur la distribution spatiale et l'évolution des objets astrophysiques (galaxies, amas des galaxies, quasars), on peut déterminer les valeurs de ces paramètres qui sont cohérentes avec ces hypothèses. Les tests cosmologiques traditionnels ont besoin de ''chandelles standards'', objets dont les propriétés intrinsèques sont indépendantes des distances. De tels objets sont probablement fictifs. Néanmoins, certains de ces tests cosmologiques peuvent être adaptés si l'évolution individuelle, ou au moins l'évolution statistique d'une population d'objets est connue. La question de la nature de l'évolution des quasars a très vite été posée et des réponses ''phénoménologiques'' ont d'abord été données. Ces réponses ne faisaient que donner une forme mathématique à l'évolution mais n'expliquaient rien de la physique duphénomène. Les premières tentatives de construction d'un modèle physique, liées au processus d'accrétion sur un trou noir et à la théorie de la formation de l'Univers ont commencé à la fin des années 80. Depuis, des dizaines de modèles tentent d'expliquer les observations, qui sont les résultats de l'étude d'objets de plus en plus nombreux. Au cours de cette thèse, le test V/Vmax a été appliqué sur l'échantillon du Large Bright Quasar Survey en montrant 1) que l'échantillon était biaisé à cause des critères de sélection et 2) que la (simple) loi de Pure Evolution en Luminosité n'était pas une bonne approximation à tout

  3. 2. Photocopied 1972 from Ecole imperiale des ponts et chaussees, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    2. Photocopied 1972 from Ecole imperiale des ponts et chaussees, Collection de Dessins Distribues aus eleves, (n.d. and no place), ORIGINAL FINK TRUSS BRIDGE, 1852. - Baltimore & Ohio Railroad, Fairmont Bridge, Spanning Monongahela River, Fairmont, Marion County, WV

  4. Le syndrome des enfants battus: aspects cliniques et radiologiques

    PubMed Central

    Jlalia, Zied; Znaigui, Talel; Smida, Mahmoud

    2016-01-01

    La maltraitance physique des enfants ou le syndrome des enfants battus est responsable de plus de 75.000 décès par an en France. Ce problème de santé publique reste sous diagnostiqué en Tunisie et dans le monde. Le chemin a été laborieux pour la reconnaissance du syndrome des enfants battus dans certaines sociétés même occidentales. Nous avons voulus exposer ce problème aux praticiens afin qu'il soit mieux diagnostiqué et pris en charge. La maltraitance physique des enfants est appelée à tort syndrome de Silverman qui ne regroupe en fait que les lésions squelettiques chez ces enfants tels que les fractures. Mots clés: Fracture, maltraitance, enfant, neuro-radiologie PMID:27642408

  5. Discovery and Classification of DES15S2kqw

    NASA Astrophysics Data System (ADS)

    Kasai, E.; Bassett, B.; Crawford, S.; Kniazev, A.; Childress, M.; D'Andrea, C.; Smith, M.; Sullivan, M.; Maartens, R.; Gupta, R.; Kovacs, E.; Kuhlmann, S.; Spinka, H.; Ahn, E.; Finley, D. A.; Frieman, J.; Marriner, J.; Wester, W.; Aldering, G.; Kim, A. G.; Thomas, R. C.; Barbary, K.; Bloom, J. S.; Goldstein, D.; Nugent, P.; Perlmutter, S.; Foley, R. J.; Casas, R.; Castander, F. J.; Desai, S.; Paech, K.; Smith, R. C.; Schubnell, M.; Kessler, R.; Lasker, J.; Scolnic, D.; Brout, D. J.; Gladney, L.; Sako, M.; Wolf, R. C.; Brown, P. J.; Krisciunas, K.; Suntzeff, N.; Nichol, R.; Papadopoulos, A.

    2015-10-01

    We report optical spectroscopy of DES15S2kqw discovered by the Dark Energy Survey. The spectrum (380-820nm) was obtained using the Robert Stobie Spectrograph (RSS) on the South African Large Telescope (SALT).

  6. RadNet Air Data From Des Moines, IA

    EPA Pesticide Factsheets

    This page presents radiation air monitoring and air filter analysis data for Des Moines, IA from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.

  7. Atmospheric and Oceanic Fluid Dynamics

    NASA Astrophysics Data System (ADS)

    Vallis, Geoffrey K.

    2006-11-01

    Fluid dynamics is fundamental to our understanding of the atmosphere and oceans. Although many of the same principles of fluid dynamics apply to both the atmosphere and oceans, textbooks tend to concentrate on the atmosphere, the ocean, or the theory of geophysical fluid dynamics (GFD). This textbook provides a comprehensive unified treatment of atmospheric and oceanic fluid dynamics. The book introduces the fundamentals of geophysical fluid dynamics, including rotation and stratification, vorticity and potential vorticity, and scaling and approximations. It discusses baroclinic and barotropic instabilities, wave-mean flow interactions and turbulence, and the general circulation of the atmosphere and ocean. Student problems and exercises are included at the end of each chapter. Atmospheric and Oceanic Fluid Dynamics: Fundamentals and Large-Scale Circulation will be an invaluable graduate textbook on advanced courses in GFD, meteorology, atmospheric science and oceanography, and an excellent review volume for researchers. Additional resources are available at www.cambridge.org/9780521849692. Includes end of chapter review questions to aid understanding Unified and comprehensive treatment of both atmospheric and oceanic fluid dynamics Covers many modern topics and provides up to date knowledge

  8. Noncommutative geometry and fluid dynamics

    NASA Astrophysics Data System (ADS)

    Das, Praloy; Ghosh, Subir

    2016-11-01

    In the present paper we have developed a Non-Commutative (NC) generalization of perfect fluid model from first principles, in a Hamiltonian framework. The noncommutativity is introduced at the Lagrangian (particle) coordinate space brackets and the induced NC fluid bracket algebra for the Eulerian (fluid) field variables is derived. Together with a Hamiltonian this NC algebra generates the generalized fluid dynamics that satisfies exact local conservation laws for mass and energy, thereby maintaining mass and energy conservation. However, nontrivial NC correction terms appear in the charge and energy fluxes. Other non-relativistic spacetime symmetries of the NC fluid are also discussed in detail. This constitutes the study of kinematics and dynamics of NC fluid. In the second part we construct an extension of the Friedmann-Robertson-Walker (FRW) cosmological model based on the NC fluid dynamics presented here. We outline the way in which NC effects generate cosmological perturbations bringing about anisotropy and inhomogeneity in the model. We also derive a NC extended Friedmann equation.

  9. Geophysical Fluid Dynamics Outreach Films

    NASA Astrophysics Data System (ADS)

    Aurnou, J. M.; Schwarz, J. W.; Noguez, G.

    2012-12-01

    Here we will present high definition films of laboratory experiments demonstrating basic fluid motions similar to those occurring in atmospheres and oceans. In these experiments, we use water to simulate the fluid dynamics of both the liquid (oceans) and gaseous (atmospheric) envelopes. To simulate the spinning of the earth, we carry out the experiments on a rotating table. For each experiment, we begin by looking at our system first without the effects of rotation. Then, we include rotation to see how the behavior of the fluid changes due to the Coriolis accelerations. Our hope is that by viewing these experiments one will develop a sense for how fluids behave both in rotating and non-rotating systems. By noting the differences between the experiments, it should then be possible to establish a basis to think about large-scale fluid motions that exist in Earth's oceans and atmospheres as well as on planets other than Earth.Plan view image of vortices in a rotating tank of fluid. Movies of such flows make accessible the often difficult to comprehend fluid dynamical processes that occur in planetary atmospheres and oceans.

  10. Fluid Flow Phenomena during Welding

    SciTech Connect

    Zhang, Wei

    2011-01-01

    MOLTEN WELD POOLS are dynamic. Liquid in the weld pool in acted on by several strong forces, which can result in high-velocity fluid motion. Fluid flow velocities exceeding 1 m/s (3.3 ft/s) have been observed in gas tungsten arc (GTA) welds under ordinary welding conditions, and higher velocities have been measured in submerged arc welds. Fluid flow is important because it affects weld shape and is related to the formation of a variety of weld defects. Moving liquid transports heat and often dominates heat transport in the weld pool. Because heat transport by mass flow depends on the direction and speed of fluid motion, weld pool shape can differ dramatically from that predicted by conductive heat flow. Temperature gradients are also altered by fluid flow, which can affect weld microstructure. A number of defects in GTA welds have been attributed to fluid flow or changes in fluid flow, including lack of penetration, top bead roughness, humped beads, finger penetration, and undercutting. Instabilities in the liquid film around the keyhole in electron beam and laser welds are responsible for the uneven penetration (spiking) characteristic of these types of welds.

  11. Quantification des besoins en intrants antipaludiques: contribution à l'actualisation des hypothèses pour la quantification des intrants de prise en charge des cas de paludisme grave en République Démocratique du Congo

    PubMed Central

    Likwela, Joris Losimba; Otokoye, John Otshudiema

    2015-01-01

    Les formes graves de paludisme à Plasmodium falciparum sont une cause majeure de décès des enfants de moins de 5 ans en Afrique Sub-saharienne. Un traitement rapide dépend de la disponibilité de médicaments appropriés au niveau des points de prestation de service. La fréquence des ruptures de stock des commodités antipaludiques, en particuliers celles utilisées pour le paludisme grave, avait nécessité une mise à jour des hypothèses de quantification. Les données issues de la collecte de routine du PNLP de 2007 à 2012 ont été comparées à celles rapportés par d'autres pays africains et utilisées pour orienter les discussions au cours d'un atelier organisé par le PNLP et ses partenaires techniques et financiers afin de dégager un consensus national. La proportion des cas de paludisme rapportés comme grave en RDC est resté autour d'une médiane de 7% avec un domaine de variation de 6 à 9%. Hormis la proportion rapportée au Kenya (2%), les pays africains ont rapporté une proportion de cas grave variant entre 5 et 7%. Il apparaît que la proportion de 1% précédemment utilisée pour la quantification en RDC a été sous-estimée dans le contexte de la gestion des cas graves sur terrain. Un consensus s'est dégagé autour de la proportion de 5% étant entendu que des efforts de renforcement des capacités seraient déployés afin d'améliorer le diagnostic au niveau des points de prestation des services. PMID:26213595

  12. Diamond growth in mantle fluids

    NASA Astrophysics Data System (ADS)

    Bureau, Hélène; Frost, Daniel J.; Bolfan-Casanova, Nathalie; Leroy, Clémence; Esteve, Imène; Cordier, Patrick

    2016-11-01

    In the upper mantle, diamonds can potentially grow from various forms of media (solid, gas, fluid) with a range of compositions (e.g. graphite, C-O-H fluids, silicate or carbonate melts). Inclusions trapped in diamonds are one of the few diagnostic tools that can constrain diamond growth conditions in the Earth's mantle. In this study, inclusion-bearing diamonds have been synthesized to understand the growth conditions of natural diamonds in the upper mantle. Diamonds containing syngenetic inclusions were synthesized in multi-anvil presses employing starting mixtures of carbonates, and silicate compositions in the presence of pure water and saline fluids (H2O-NaCl). Experiments were performed at conditions compatible with the Earth's geotherm (7 GPa, 1300-1400 °C). Results show that within the timescale of the experiments (6 to 30 h) diamond growth occurs if water and carbonates are present in the fluid phase. Water promotes faster diamond growth (up to 14 mm/year at 1400 °C, 7 GPa, 10 g/l NaCl), which is favorable to the inclusion trapping process. At 7 GPa, temperature and fluid composition are the main factors controlling diamond growth. In these experiments, diamonds grew in the presence of two fluids: an aqueous fluid and a hydrous silicate melt. The carbon source for diamond growth must be carbonate (CO32) dissolved in the melt or carbon dioxide species in the aqueous fluid (CO2aq). The presence of NaCl affects the growth kinetics but is not a prerequisite for inclusion-bearing diamond formation. The presence of small discrete or isolated volumes of water-rich fluids is necessary to grow inclusion-bearing peridotitic, eclogitic, fibrous, cloudy and coated diamonds, and may also be involved in the growth of ultradeep, ultrahigh-pressure metamorphic diamonds.

  13. Detachment energies of spheroidal particles from fluid-fluid interfaces

    NASA Astrophysics Data System (ADS)

    Davies, Gary B.; Krüger, Timm; Coveney, Peter V.; Harting, Jens

    2014-10-01

    The energy required to detach a single particle from a fluid-fluid interface is an important parameter for designing certain soft materials, for example, emulsions stabilised by colloidal particles, colloidosomes designed for targeted drug delivery, and bio-sensors composed of magnetic particles adsorbed at interfaces. For a fixed particle volume, prolate and oblate spheroids attach more strongly to interfaces because they have larger particle-interface areas. Calculating the detachment energy of spheroids necessitates the difficult measurement of particle-liquid surface tensions, in contrast with spheres, where the contact angle suffices. We develop a simplified detachment energy model for spheroids which depends only on the particle aspect ratio and the height of the particle centre of mass above the fluid-fluid interface. We use lattice Boltzmann simulations to validate the model and provide quantitative evidence that the approach can be applied to simulate particle-stabilized emulsions, and highlight the experimental implications of this validation.

  14. Cout de Maintenance et Duree de Vie des Turbomoteurs

    DTIC Science & Technology

    2003-02-01

    UNCLASSIFIED Defense Technical Information Center Compilation Part Notice ADP014136 TITLE: Cout de Maintenance et Duree de Vie des Turbomoteurs...termes op~rationnels et de gestion de flotte moteurs en service, il est cofiteux. Communication prisentge lors dit sYmiposium RTO A UTsur (f Les...macanismes vieillissants et le contrrle: Partie B - Le suivi et la gestion des turbomoteurs en vue Ai prolongement de leur durae de vie et de la

  15. Fehlertoleranzanalyse des FlexRay Startup-Prozesses

    NASA Astrophysics Data System (ADS)

    Bünte, Sven; Milbredt, Paul

    Die PlexfiRay-Prozeduren Wakeup und Startup sollen eine konsistent-synchrone Kommunikation bezüglich eines TDMA verwandten Verfuhrens herstellen. Beide Algorithmen werden in dieser Arbeit ubstrukt modelliert und mit Hilfe des Model Checkers SPIN bezüglich Terminierung analysiert. Die Ergebnisse zeigen, dass in bestimmten Fehlerszenarios die Verwendung von Central Bus Guardians, die Clusterkonfiguration und das Verhalten des Hosts darüber entscheiden, ob Fehlertoleranz und Laufzeitbeschränkungen garantiert werden können.

  16. Quantum field theory of fluids.

    PubMed

    Gripaios, Ben; Sutherland, Dave

    2015-02-20

    The quantum theory of fields is largely based on studying perturbations around noninteracting, or free, field theories, which correspond to a collection of quantum-mechanical harmonic oscillators. The quantum theory of an ordinary fluid is "freer", in the sense that the noninteracting theory also contains an infinite collection of quantum-mechanical free particles, corresponding to vortex modes. By computing a variety of correlation functions at tree and loop level, we give evidence that a quantum perfect fluid can be consistently formulated as a low-energy, effective field theory. We speculate that the quantum behavior is radically different from both classical fluids and quantum fields.

  17. Finite element computational fluid mechanics

    NASA Technical Reports Server (NTRS)

    Baker, A. J.

    1983-01-01

    Finite element analysis as applied to the broad spectrum of computational fluid mechanics is analyzed. The finite element solution methodology is derived, developed, and applied directly to the differential equation systems governing classes of problems in fluid mechanics. The heat conduction equation is used to reveal the essence and elegance of finite element theory, including higher order accuracy and convergence. The algorithm is extended to the pervasive nonlinearity of the Navier-Stokes equations. A specific fluid mechanics problem class is analyzed with an even mix of theory and applications, including turbulence closure and the solution of turbulent flows.

  18. Spinning fluids in general relativity

    NASA Technical Reports Server (NTRS)

    Ray, J. R.; Smalley, L. L.

    1982-01-01

    General relativity field equations are employed to examine a continuous medium with internal spin. A variational principle formerly applied in the special relativity case is extended to the general relativity case, using a tetrad to express the spin density and the four-velocity of the fluid. An energy-momentum tensor is subsequently defined for a spinning fluid. The equations of motion of the fluid are suggested to be useful in analytical studies of galaxies, for anisotropic Bianchi universes, and for turbulent eddies.

  19. The Basic Physical Mechanism for Disconnection Events(DEs)

    NASA Astrophysics Data System (ADS)

    Brandt, J. C.

    2004-11-01

    Disconnection Events (DEs) are arguably the most dramatic phenomena in cometary physics. The entire plasma tail disconnects from the head, and image sequences have been available for approximately one century. Many details were known to Barnard (1899, 1908, 1920) and his contemporaries. Modern DE studies began with the rediscovery of the phenomena by Niedner & Brandt (1978) and their proposal that the physical mechanism was the severing of the magnetic field lines by magnetic reconnection at crossings of the heliospheric current sheet (HCS). While many areas of investigation-direct spacecraft observations (Niedner & Schwingenschuh 1987; Verigin et al. 1987; Kirsch et al. 1989); associations of DEs with solar-wind features (Niedner & Brandt 1979; Yi et al. 1994; Brandt et al. 1999); and magnetohydrodynamic (MHD) simulations of DEs (Yi et al. 1996)-strongly supported this physical mechanism, areas of concern or disagreement remained (e.g., Farnham & Meech 1994; Wegmann 1995, 1998, 2000). Recent results seem to resolve the problems in all areas. The associations of DEs with solar-wind features have been extensively reinvestigated (Niedner et al. 2005). In particular, many high-speed streams are not associated with the HCS (as many as 40%) and these high-speed streams are definitely not associated with DEs. Finally, Konz et al. (2004) have reproduced DEs at crossings of the HCS using plasma-neutral gas simulations with anomalous resistivity. The new evidence strongly confirms the sunward, magnetic reconnection physical mechanism proposed by Niedner & Brandt (1978).

  20. Standardization of Thermo-Fluid Modeling in Modelica.Fluid

    SciTech Connect

    Franke, Rudiger; Casella, Francesco; Sielemann, Michael; Proelss, Katrin; Otter, Martin; Wetter, Michael

    2009-09-01

    This article discusses the Modelica.Fluid library that has been included in the Modelica Standard Library 3.1. Modelica.Fluid provides interfaces and basic components for the device-oriented modeling of onedimensional thermo-fluid flow in networks containing vessels, pipes, fluid machines, valves and fittings. A unique feature of Modelica.Fluid is that the component equations and the media models as well as pressure loss and heat transfer correlations are decoupled from each other. All components are implemented such that they can be used for media from the Modelica.Media library. This means that an incompressible or compressible medium, a single or a multiple substance medium with one or more phases might be used with one and the same model as long as the modeling assumptions made hold. Furthermore, trace substances are supported. Modeling assumptions can be configured globally in an outer System object. This covers in particular the initialization, uni- or bi-directional flow, and dynamic or steady-state formulation of mass, energy, and momentum balance. All assumptions can be locally refined for every component. While Modelica.Fluid contains a reasonable set of component models, the goal of the library is not to provide a comprehensive set of models, but rather to provide interfaces and best practices for the treatment of issues such as connector design and implementation of energy, mass and momentum balances. Applications from various domains are presented.

  1. Extension of Generalized Fluid System Simulation Program's Fluid Property Database

    NASA Technical Reports Server (NTRS)

    Patel, Kishan

    2011-01-01

    This internship focused on the development of additional capabilities for the General Fluid Systems Simulation Program (GFSSP). GFSSP is a thermo-fluid code used to evaluate system performance by a finite volume-based network analysis method. The program was developed primarily to analyze the complex internal flow of propulsion systems and is capable of solving many problems related to thermodynamics and fluid mechanics. GFSSP is integrated with thermodynamic programs that provide fluid properties for sub-cooled, superheated, and saturation states. For fluids that are not included in the thermodynamic property program, look-up property tables can be provided. The look-up property tables of the current release version can only handle sub-cooled and superheated states. The primary purpose of the internship was to extend the look-up tables to handle saturated states. This involves a) generation of a property table using REFPROP, a thermodynamic property program that is widely used, and b) modifications of the Fortran source code to read in an additional property table containing saturation data for both saturated liquid and saturated vapor states. Also, a method was implemented to calculate the thermodynamic properties of user-fluids within the saturation region, given values of pressure and enthalpy. These additions required new code to be written, and older code had to be adjusted to accommodate the new capabilities. Ultimately, the changes will lead to the incorporation of this new capability in future versions of GFSSP. This paper describes the development and validation of the new capability.

  2. Identification et prise en charge des femmes ayant des antécédents familiaux de cancer du sein

    PubMed Central

    Heisey, Ruth; Carroll, June C.

    2016-01-01

    Résumé Objectif Résumer les meilleures données portant sur les stratégies d’identification et de prise en charge des femmes qui présentent des antécédents familiaux de cancer du sein. Sources d’information Une recherche a été effectuée sur PubMed à l’aide des mots-clés anglais suivants : breast cancer, guidelines, risk, family history, management et magnetic resonance imaging screening, entre 2000 et 2016. La plupart des données sont de niveau II. Message principal Une bonne anamnèse familiale est essentielle lors de l’évaluation du risque de cancer du sein afin d’identifier les femmes qui sont candidates à une recommandation en counseling génétique pour un éventuel test génétique. On peut sauver des vies en offrant aux femmes porteuses d’une mutation au gène BRCA des interventions chirurgicales de réduction des risques (mastectomie bilatérale prophylactique, salpingo-ovariectomie bilatérale). Il faut encourager toutes les femmes qui présentent des antécédents familiaux de cancer du sein à demeurer actives et à limiter leur consommation d’alcool à moins de 1 verre par jour; certaines femmes sont admissibles à la chimioprévention. Il faut offrir aux femmes dont le risque à vie de cancer du sein est de 20 à 25 % ou plus un dépistage poussé par imagerie par résonance magnétique en plus d’une mammographie. Conclusion Une vie saine et la chimioprévention (chez les candidates) pourraient réduire l’incidence du cancer du sein; le dépistage poussé pourrait entraîner une détection plus précoce. Le fait d’aiguiller des femmes porteuses d’une mutation au BRCA vers la chirurgie de réduction des risques sauve des vies. PMID:27737991

  3. [Le leadership en santé et l'éthique de la gestion des attentes des soignants et des patients].

    PubMed

    Browne, Alister

    2016-03-01

    Les dispensateurs de soins et les patients sont souvent déçus du niveau de soins que les hôpitaux publics peuvent prodiguer. La solution consiste à réduire les attentes. Les dispensateurs devraient être amenés à considérer que leur obligation consiste à prodiguer les meilleurs soins en fonction des ressources. Le public devrait être bien informé des services que les hôpitaux de soins actifs peuvent ou non lui offrir et participer aux prises de décision. Les leaders en santé peuvent jouer des rôles novateurs à cet égard.

  4. Technical Evaluation Report on the Guidance and Control Panel 53rd Symposium on Air Vehicle Mission Control and Management (La Gestion et le Controle des Missions des Vehicules Aeriens)

    DTIC Science & Technology

    1992-07-01

    d’importance dans le guidage et le pilotage des vehicules aeriens. Les developpements dans ce domaine representent des contributions d’une importance...d’un vehicule non-pilots. fonctionner en mode automatique. Les communications techniques ont examine les realisations et les tendances actuelles dans...le domaine de la gestion des missions des vehicules aeriens, presente !’tat de I’art et propos, des solutions technologiques pour la conception des

  5. Rôle des hyrates dans la formation de Titan et des satellites réguliers

    NASA Astrophysics Data System (ADS)

    Mousis, O.

    2001-12-01

    Cette these est dediee a l'etude de l'origine de Titan et de son atmosphere. Dans l'hypothese ou la subnebuleuse de Saturne etait geometriquement mince, le modele de disque turbulent utilise, derive des travaux de Dubrulle (1993), est moins dense que le modele de Prinn et Fegley (1981). De ce fait, les conversions de Co en CH4 et de N2 en NH3 ont ete inhibees dans la subnebuleuse, contrairement a ce qui est couramment admis pour interpreter la presence du methane dans l'atmosphere de Titan. C'est pourquoi nous avons developpe un nouveau scenario de la formation de titan, qui tient compte simultanement des contraintes resultant de la chimie de la subnebuleuse et des abondances de CH4, N2 et CH3D mesurees dans l'atmosphere du satellite. Nous faisons l'hypothese que ces gaz proviennent initialement de la vaporisation du nuage presolaire, qui s'effondra et forma le Soleil et son disque environnant. Lors du refroidissement de la nebuleuse, les volatils auraient ete pieges sous formes de clathrates d'hydrates dans les grains, puis dans les planetesimaux qu'ils formerent. Les planetesimaux hydrates a l'origine de la formation de Titan seraient alors des rescapes de l'effondrement hydsrodynamique de la feeding zone de Saturne. Ce scenario a ete applique aux subnebuleuses de Jupiter et d'Uranus, et a apporte un certain nombre de contraintes sur la formation des satellites reguliers de ces planetes. Le temps et la zone de formation des grains cometaires ont egalement ete estimes dans la nebuleuse solaire. Enfin, l'etude experimentale de la temperature de fusion du dihydrate d'ammoniac dans la gamme des hautes pressions a apporte des nouvelles donnees thermodynamiques qui permettront d'ameliorer les modeles de l'interieur de Titan.

  6. The Variety of Fluid Dynamics.

    ERIC Educational Resources Information Center

    Barnes, Francis; And Others

    1980-01-01

    Discusses three research topics which are concerned with eminently practical problems and deal at the same time with fundamental fluid dynamical problems. These research topics come from the general areas of chemical and biological engineering, geophysics, and pure mathematics. (HM)

  7. Fluid management systems technology summaries

    NASA Technical Reports Server (NTRS)

    Stark, J. A.; Blatt, M. H.; Bennett, F. O., Jr.; Campbell, B. J.

    1974-01-01

    A summarization and categorization of the pertinent literature associated with fluid management systems technology having potential application to in-orbit fluid transfer and/or associated storage are presented. A literature search was conducted to obtain pertinent documents for review. Reports determined to be of primary significance were summarized in the following manner: (1) report identification, (2) objective(s) of the work, (3) description of pertinent work performed, (4) major results, and (5) comments of the reviewer. Pertinent figures are presented on a single facing page separate from the text. Specific areas covered are: fluid line dynamics and thermodynamics, low-g mass gauging, other instrumentation, stratification/pressurization, low-g vent systems, fluid mixing refrigeration and reliquefaction, and low-g interface control and liquid acquisition systems. Reports which were reviewed and not summarized, along with reasons for not summarizing, are also listed.

  8. Fluid Instabilities inside Astrophysical Explosions

    NASA Astrophysics Data System (ADS)

    Chen, Ke-Jung; Woosley, Stan; Heger, Alexander; Almgren, Ann; Zheng, Weiqun

    2014-11-01

    We present our results from the simulations of fluid instabilities inside supernovae with a new radiation-hydrodynamic code, CASTRO. Massive stars are ten times more massive than Sun. Observational and theoretical studies suggest that these massive stars tend to end their lives with energetic explosions, so-called supernovae. Many fluid instabilities occur during the supernova explosions. The fluid instabilities can be driven by hydrodynamics, nuclear burning, or radiation. In this talk, we discuss about the possible physics of fluid instabilities found in our simulations and how the resulting mixing affects the observational signatures of supernovae. This work was supported by the DOE HEP Program under contract DE-SC0010676; the National Science Foundation (AST 0909129) and the NASA Theory Program (NNX14AH34G).

  9. FLUID TRANSPORT THROUGH POROUS MEDIA

    EPA Science Inventory

    Fluid transport through porous media is a relevant topic to many scientific and engineering fields. Soil scientists, civil engineers, hydrologists and hydrogeologists are concerned with the transport of water, gases and nonaqueous phase liquid contaminants through porous earth m...

  10. Fluid Mechanics Can Be Fun.

    ERIC Educational Resources Information Center

    Blanks, Robert F.

    1979-01-01

    A humanistic approach to teaching fluid mechanics is described which minimizes lecturing, increases professor-student interaction, uses group and individual problem solving sessions, and allows for student response. (BB)

  11. Improved perfluoroalkyl ether fluid development

    NASA Technical Reports Server (NTRS)

    Jones, William R., Jr.; Paciorek, Kazimiera J. L.; Nakahara, James H.; Smythe, Mark E.; Kratzer, Reinhold H.

    1987-01-01

    The feasibility of transforming a commercial linear perfluoroalkylether fluid into a material stable in the presence of metals and metal alloys in oxidizing atmospheres at 300 C without the loss of the desirable viscosity temperature characteristics was determined. The approach consisted of thermal oxidative treatment in the presence of catalyst to remove weak links, followed by transformation of the created functional groups into phospha-s-triazine linkages. It is found that the experimental material obtained in 66 percent yield from the commercial fluid exhibits, over an 8 hr period at 300 C in the presence of Ti(4Al, 4Mn) alloy, thermal oxidative stability better by a factor of 2.6 x 1000 based on volatiles evolved than the commercial product. The viscosity and molecular weight of the developed fluid are unchanged and are essentially identical with the commercial material. No metal corrosion occurs with the experimental fluid at 300 C.

  12. The handbook of fluid dynamics

    SciTech Connect

    Johnson, R.W.

    1998-07-01

    This book provides professionals in the field of fluid dynamics with a comprehensive guide and resource. The book balances three traditional areas of fluid mechanics--theoretical, computational, and experimental--and expounds on basic science and engineering techniques. Each chapter introduces a topic, discusses the primary issues related to this subject, outlines approaches taken by experts, and supplies references for further information. Topics discussed include: (1) basic engineering fluid dynamics; (2) classical fluid dynamics; (3) turbulence modeling; (4) reacting flows; (5) multiphase flows; (6) flow and porous media; (7) high Reynolds number asymptotic theories; (8) finite difference method; (9) finite volume method; (10) finite element methods; (11) spectral element methods for incompressible flows; (12) experimental methods, such as hot-wire anemometry, laser-Doppler velocimetry, and flow visualization; and (13) applications, such as axial-flow compressor and fan aerodynamics, turbomachinery, airfoils and wings, atmospheric flows, and mesoscale oceanic flows.

  13. PREFACE: XXI Fluid Mechanics Conference

    NASA Astrophysics Data System (ADS)

    Szmyd, Janusz S.; Fornalik-Wajs, Elzbieta; Jaszczur, Marek

    2014-08-01

    This Conference Volume contains the papers presented at the 21st Fluid Mechanics Conference (XXI FMC) held at AGH - University of Science and Technology in Krakow, Poland, 15-18 June 2014, and accepted for Proceedings published in the Journal of Physics: Conference Series. The Fluid Mechanics Conferences have been taking place every two years since 1974, a total of forty years. The 21st Fluid Mechanics Conference (XXI FMC) is being organized under the auspices of the Polish Academy of Sciences, Committee of Mechanics. The goal of this conference is to provide a forum for the exposure and exchange of ideas, methods and results in fluid mechanics. Conference topics include, but are not limited to Aerodynamics, Atmospheric Science, Bio-Fluids, Combustion and Reacting Flows, Computational Fluid Dynamics, Experimental Fluid Mechanics, Flow Machinery, General Fluid Dynamics, Hydromechanics, Heat and Fluid Flow, Measurement Techniques, Micro- and Nano- Flow, Multi-Phase Flow, Non-Newtonian Fluids, Rotating and Stratified Flows, Turbulence. Within the general subjects of this conference, the Professor Janusz W. Elsner Competition for the best fluid mechanics paper presented during the Conference is organized. Authors holding a M.Sc. or a Ph.D. degree and who are not older than 35 years of age may enter the Competition. Authors with a Ph.D. degree must present individual papers; authors with a M.Sc. degree may present papers with their supervisor as coauthor, including original results of experimental, numerical or analytic research. Six state-of-the-art keynote papers were delivered by world leading experts. All contributed papers were peer reviewed. Recommendations were received from the International Scientific Committee, reviewers and the advisory board. Accordingly, of the 163 eligible extended abstracts submitted, after a review process by the International Scientific Committee, 137 papers were selected for presentation at the 21st Fluid Mechanics Conference, 68

  14. Oil emulsions of fluorosilicone fluids

    SciTech Connect

    Keil, J. W.

    1985-08-27

    Emulsions of fluorosilicone fluids in mineral oil are disclosed. These emulsions are stabilized by a polydimethylsiloxane-polybutadiene copolymer or a polydimethylsiloxane-hydrogenated polybutadiene copplymer. The emulsions are an effective foam suppressant for organic liquids, especially crude petroleum.

  15. Stellar Astrophysical Fluid Dynamics

    NASA Astrophysics Data System (ADS)

    Thompson, Michael J.; Christensen-Dalsgaard, Jørgen

    2008-02-01

    Preface; 1. A selective overview Jørgen Christensen-Dalsgaard and Michael J. Thompson; Part I. Stellar Convection and Oscillations: 2. On the diversity of stellar pulsations Wojciech A. Dziembowski; 3. Acoustic radiation and mode excitation by turbulent convection Günter Houdek; 4. Understanding roAp stars Margarida S. Cunha; 5. Waves in the magnetised solar atmosphere Colin S. Rosenthal; Part II. Stellar Rotation and Magnetic Fields: 6. Stellar rotation: a historical survey Leon Mestel; 7. The oscillations of rapidly rotating stars Michel Rieutord; 8. Solar tachocline dynamics: eddy viscosity, anti-friction, or something in between? Michael E. McIntyre; 9. Dynamics of the solar tachocline Pascale Garaud; 10. Dynamo processes: the interaction of turbulence and magnetic fields Michael Proctor; 11. Dynamos in planets Chris Jones; Part III. Physics and Structure of Stellar Interiors: 12. Solar constraints on the equation of state Werner Däppen; 13. 3He transport and the solar neutrino problem Chris Jordinson; 14. Mixing in stellar radiation zones Jean-Paul Zahn; 15. Element settling and rotation-induced mixing in slowly rotating stars Sylvie Vauclair; Part IV. Helio- and Asteroseismology: 16. Solar structure and the neutrino problem Hiromoto Shibahashi; 17. Helioseismic data analysis Jesper Schou; 18. Seismology of solar rotation Takashi Sekii; 19. Telechronohelioseismology Alexander Kosovichev; Part V. Large-Scale Numerical Experiments: 20. Bridges between helioseismology and models of convection zone dynamics Juri Toomre; 21. Numerical simulations of the solar convection zone Julian R. Elliott; 22. Modelling solar and stellar magnetoconvection Nigel Weiss; 23. Nonlinear magnetoconvection in the presence of a strong oblique field Keith Julien, Edgar Knobloch and Steven M. Tobias; 24. Simulations of astrophysical fluids Marcus Brüggen; Part VI. Dynamics: 25. A magic electromagnetic field Donald Lynden-Bell; 26. Continuum equations for stellar dynamics Edward A

  16. Stellar Astrophysical Fluid Dynamics

    NASA Astrophysics Data System (ADS)

    Thompson, Michael J.; Christensen-Dalsgaard, Jørgen

    2003-05-01

    Preface; 1. A selective overview Jørgen Christensen-Dalsgaard and Michael J. Thompson; Part I. Stellar Convection and Oscillations: 2. On the diversity of stellar pulsations Wojciech A. Dziembowski; 3. Acoustic radiation and mode excitation by turbulent convection Günter Houdek; 4. Understanding roAp stars Margarida S. Cunha; 5. Waves in the magnetised solar atmosphere Colin S. Rosenthal; Part II. Stellar Rotation and Magnetic Fields: 6. Stellar rotation: a historical survey Leon Mestel; 7. The oscillations of rapidly rotating stars Michel Rieutord; 8. Solar tachocline dynamics: eddy viscosity, anti-friction, or something in between? Michael E. McIntyre; 9. Dynamics of the solar tachocline Pascale Garaud; 10. Dynamo processes: the interaction of turbulence and magnetic fields Michael Proctor; 11. Dynamos in planets Chris Jones; Part III. Physics and Structure of Stellar Interiors: 12. Solar constraints on the equation of state Werner Däppen; 13. 3He transport and the solar neutrino problem Chris Jordinson; 14. Mixing in stellar radiation zones Jean-Paul Zahn; 15. Element settling and rotation-induced mixing in slowly rotating stars Sylvie Vauclair; Part IV. Helio- and Asteroseismology: 16. Solar structure and the neutrino problem Hiromoto Shibahashi; 17. Helioseismic data analysis Jesper Schou; 18. Seismology of solar rotation Takashi Sekii; 19. Telechronohelioseismology Alexander Kosovichev; Part V. Large-Scale Numerical Experiments: 20. Bridges between helioseismology and models of convection zone dynamics Juri Toomre; 21. Numerical simulations of the solar convection zone Julian R. Elliott; 22. Modelling solar and stellar magnetoconvection Nigel Weiss; 23. Nonlinear magnetoconvection in the presence of a strong oblique field Keith Julien, Edgar Knobloch and Steven M. Tobias; 24. Simulations of astrophysical fluids Marcus Brüggen; Part VI. Dynamics: 25. A magic electromagnetic field Donald Lynden-Bell; 26. Continuum equations for stellar dynamics Edward A

  17. Mecanique et mecanisme de la dechirure des materiaux textiles

    NASA Astrophysics Data System (ADS)

    Triki, Ennouri

    Cette thèse vise à apporter une contribution à l’étude et à la modélisation de la déchirure des textiles et des textiles enduits. Notons que la résistance à la déchirure est l’une des caractéristiques mesurées pour les équipements de protection contre les agresseurs mécaniques en milieu de travail. Jusqu'à présent, ce comportement en déchirure a été étudié en mesurant la force de déchirure et le travail de déchirure. De fait, aucun critère de rupture en déchirure n’existe actuellement. Par conséquent, en s’inspirant de la théorie du Griffith et de la mécanique de la rupture, une formulation d’un nouveau critère de rupture des structures textiles a été proposée. Cette approche offre la possibilité de déterminer d’une manière plus précise l’énergie nécessaire pour la création d’une nouvelle surface de rupture. Ce critère nous permet d’analyser l’effet des caractéristiques des tissus sur la variation de l’énergie de rupture. Cette étude montre que la résistance au glissement des fils dans la structure est le principal facteur qui contrôle la propagation de la fissure. En se basant sur la théorie de la mécanique de la rupture, un modèle de calcul de l’énergie de rupture par déchirure a été aussi élaboré. Ce modèle de déchirure relie l’énergie aux paramètres caractérisant les phénomènes affectant la déchirure des tissus, notamment la force de glissement et la force à la rupture des fils. Cette modélisation a tenu compte de certaines caractéristiques des tissus tels que l’épaisseur du matériau, la densité des fils, etc. Par l’étude de la variation de l’énergie de rupture par déchirure en fonction du rapport établi entre la force à la rupture et la force de glissement d’un fil ( FYB/FS), l’effet des mécanismes de la propagation de la fissure dans les tissus sur leur comportement en déchirure a été aussi observé. Les résultats obtenus

  18. Apparatus for Pumping a Fluid

    NASA Technical Reports Server (NTRS)

    Boeyen, Robert Van; Reeh, Jonathan

    2013-01-01

    A fluid pump has been developed for mechanically pumped fluid loops for spacecraft thermal control. Lynntech's technology utilizes a proprietary electrochemically driven pumping mechanism. Conventional rotodynamic and displacement pumps typically do not meet the stringent power and operational reliability requirements of space applications. Lynntech's developmental pump is a highly efficient solid-state pump with essentially no rotating or moving components (apart from metal bellows).

  19. Borehole drilling fluid and method

    SciTech Connect

    Carriere, D.B.; Lauzon, R.V.

    1981-11-17

    An improved drilling fluid and method for drilling a borehole, the drilling fluid comprising an aqueous dispersion of an emulsion polymerized latex comprised of an interpolymer of an olefinically unsaturated carboxylic acid monomer and at least one other, non-carboxylated polymerizable monomer, the latex being of a type which undergoes rapid increase in viscosity upon the addition of a sufficient amount of a basic material.

  20. Borehole drilling fluid and method

    SciTech Connect

    Carriere, D. B.; Lauzon, R. V.

    1984-12-04

    An improved drilling fluid and method for drilling a borehole, the drilling fluid comprising an aqueous dispersion of an emulsion polymerized latex comprised of an interpolymer of an olefinically unsaturated carboxylic acid monomer and at least one other, non-carboxylated polymerizable monomer, the latex being of a type which undergoes rapid increase in viscosity upon the addition of a sufficient amount of a basic material.

  1. Fracturing fluid characterization facility (FFCF)

    SciTech Connect

    Evans, R.D.; Roegiers, J.C.; Fagan, J.

    1993-12-31

    The Fracturing Fluid Characterization Facility project has as its main focus the design, fabrication, and construction of a high pressure simulator (HPS) and a low pressure simulator (LPS) to be used to experimentally investigate the rheological properties and transport characteristics of proppant laden fracturing fluids. A discussion of each apparatus is provided as well as the auxiliary equipment, and data acquisition and control systems associated with the simulators.

  2. C3I for Crisis, Emergency and Consequence Management (C3I pour la gestion des crises, des urgences et de leurs consequences)

    DTIC Science & Technology

    2009-05-01

    May 2009 C3I for Crisis, Emergency and Consequence Management (C3I pour la gestion des crises , des urgences et de leurs conséquences) Research and...consequence management. ES - 2 RTO-MP-IST-086 C3I pour la gestion des crises , des urgences et de leurs conséquences (RTO-MP-IST-086...contre-terrorisme, de sécurité nationale/publique et de réponse collective face aux situations d’urgence (à la fois gestion des crises et gestion de leurs

  3. Reconnaissance optique des formes en parallele utilisant des reseaux de neurones et une mire de reduction de dimensions

    NASA Astrophysics Data System (ADS)

    Gagne, Philippe

    Cette recherche vise à la mise en OEuvre optique de la reconnaissance des images en utilisant une mire d'anneaux afin de générer des vecteurs caractéristiques qui seront ensuite classifiés par un réseau de neurones. On proposera deux architectures originales: une qui permettra la reconnaissance invariante sous rotation en utilisant un corrélateur conjoint; l'autre montage permettra une classification en parallèle de plusieurs images grâce à la capacité des mires d'anneaux de compresser l'information. Ce dernier montage est basé sur un corrélateur 4F. On présentera des résultats optiques expérimentaux pour ces deux montages. Pour arriver à des résultats concluants on analysera le comportement des vecteurs obtenus à partir d'une mire d'anneaux, on introduira une règle d'apprentissage optimisant le pic de corrélation en réduisant les pics parasites et on corrigera à l'aide d'un algorithme génétique les modulations de phases générées par le modulateur spatial à cristaux liquides.

  4. Cosmology with moving bimetric fluids

    NASA Astrophysics Data System (ADS)

    García-García, Carlos; Maroto, Antonio L.; Martín-Moruno, Prado

    2016-12-01

    We study cosmological implications of bigravity and massive gravity solutions with non-simultaneously diagonal metrics by considering the generalized Gordon and Kerr-Schild ansatzes. The scenario that we obtain is equivalent to that of General Relativity with additional non-comoving perfect fluids. We show that the most general ghost-free bimetric theory generates three kinds of effective fluids whose equations of state are fixed by a function of the ansatz. Different choices of such function allow to reproduce the behaviour of different dark fluids. In particular, the Gordon ansatz is suitable for the description of various kinds of slowly-moving fluids, whereas the Kerr-Schild one is shown to describe a null dark energy component. The motion of those dark fluids with respect to the CMB is shown to generate, in turn, a relative motion of baryonic matter with respect to radition which contributes to the CMB anisotropies. CMB dipole observations are able to set stringent limits on the dark sector described by the effective bimetric fluid.

  5. A Kinetic-fluid Model

    SciTech Connect

    First Author = C.Z. Cheng; Jay R. Johnson

    1998-07-10

    A nonlinear kinetic-fluid model for high-beta plasmas with multiple ion species which can be applied to multiscale phenomena is presented. The model embeds important kinetic effects due to finite ion Larmor radius (FLR), wave-particle resonances, magnetic particle trapping, etc. in the framework of simple fluid descriptions. When further restricting to low frequency phenomena with frequencies less than the ion cyclotron frequency the kinetic-fluid model takes a simpler form in which the fluid equations of multiple ion species collapse into single-fluid density and momentum equations and a low frequency generalized Ohm's law. The kinetic effects are introduced via plasma pressure tensors for ions and electrons which are computed from particle distribution functions that are governed by the Vlasov equation or simplified plasma dynamics equations such as the gyrokinetic equation. The ion FLR effects provide a finite parallel electric field, a perpendicular velocity that modifies the ExB drift, and a gyroviscosity tensor, all of which are neglected in the usual one-fluid MHD description. Eigenmode equations are derived which include magnetosphere-ionosphere coupling effects for low frequency waves (e.g., kinetic/inertial Alfven waves and ballooning-mirror instabilities).

  6. Les sarcomes des tissus mous: à propos de 33 cas

    PubMed Central

    Abdou, Jiddou; Elkabous, Mustapha; M'rabti, Hind; Errihani, Hassan

    2015-01-01

    L'objectif de cette étude est de rapporter les particularités épidémiologiques, cliniques, histologiques, thérapeutiques et évolutives des sarcomes des tissus mous à l'Institut National d'Oncologie et de définir les facteurs influençant la survie des patients. C'est une étude rétrospective de 33 cas de sarcome des tissus mous, colligés entre janvier 2008 et décembre 2010. Les critères d’éligibilité étaient un âge supérieur à 16 ans, une épreuve histologique d'un sarcome des tissus mous à l'exclusion des tumeurs stromales gastro-intestinales (GIST). Les items recueillis étaient: épidémiologiques, cliniques, histologiques, Radiologiques, et thérapeutiques. Des analyses univariées puis multivariées ont été réalisées à la recherche de facteurs influençant la survie à 2 ans. Il s'agit de 33 cas, 17 Hommes et 16 Femmes, l’âge moyen était de 43,21 ans (Extrêmes= 18-76 ans). La tumeur était localisée aux extrémités dans 24 cas (72,72%). Le type histologique prédominant était le Liposarcome dans 9 cas (27,27%). Le stade tumoral était localisé dans 25 cas (75,8%), métastatique dans 8 cas (24,2%). Vingt-cinq tumeurs ont été traitées chirurgicalement dont 21 cas (84%) de chirurgie conservatrice et 4 cas (16%) de chirurgie radicale. La radiothérapie a été réalisée chez 10 patients (30,3%). La chimiothérapie a été faite chez 20 patients. En analyse univariée les facteurs pronostiques étaient l’âge (p=0,03) et le stade tumoral (p=0,09). L’âge et le stade tumoral sont des facteurs pronostiques influençant la survie des sarcomes des tissus mous. PMID:27022434

  7. Nouvelle approche à la prise en charge des condylomes

    PubMed Central

    Lopaschuk, Catharine C.

    2013-01-01

    Résumé Objectif Faire le résumé des anciens et des nouveaux moyens de traitement des verrues génitales ou condylomes et déterminer comment les utiliser de manière appropriée. Sources des données Une recherche documentaire a été effectuée dans les bases de données suivantes: MEDLINE, PubMed, EMBASE, base de données des synthèses systématiques et registre central des études contrôlées de la Collaboration Cochrane (en anglais), ACP Journal Club et Trip. Les bibliographies des articles extraits ont aussi été examinées. Les études cliniques, les articles de révision qualitative, les rapports consensuels et les guides de pratique clinique ont été retenus. Message principal Les verrues symptomatiques sont présentes chez au moins 1 % des personnes âgées entre 15 et 49 ans et on estime que jusqu’à 50 % des gens sont infectés par le virus du papillome humain à un moment donné de leur vie. L’imiquimod et la podophyllotoxine sont 2 nouveaux traitements pour les verrues génitales externes qui sont moins douloureux et peuvent être appliqués par les patients à la maison. De plus, il a été démontré que le vaccin quadrivalent contre le virus du papillome humain est efficace pour prévenir les condylomes et le cancer du col. Les plus anciennes méthodes thérapeutiques ont aussi leur place dans certaines situations, comme les verrues intravaginales, urétrales, anales ou récalcitrantes ou encore pour les patientes enceintes. Conclusion Les nouveaux traitements des verrues génitales externes peuvent réduire la douleur causée par la thérapie et le nombre de visites au cabinet. Les autres méthodes thérapeutiques demeurent utiles dans certaines situations.

  8. CFD Simulations of a Ferry in Head Seas

    DTIC Science & Technology

    2011-03-01

    vibration de frottement qui exerce une contrainte sur la structure de coque primaire et qui a un effet défavorable sur la durée de vie en fatigue globale du...provoquer des avaries locales, mais aussi pour entraîner une vibration de frottement qui exerce une contrainte sur la structure de coque primaire et qui a...100 END END MONITOR OBJECTS: Monitor Coefficient Loop Convergence = False MONITOR BALANCES: Option = Full END MONITOR FORCES: Option = Full END

  9. Caractérisation des convertisseurs matriciels : II. Synthèse des fonctions de connexion

    NASA Astrophysics Data System (ADS)

    François, B.; Cambronne, J. P.; Hautier, J. P.

    1996-05-01

    Knowing the wished conversion levels (-1,0,1) of a power converter, this paper describes a particular method for setting the corresponding states of switches into the matrix converter. In a first step, a mathematical analysis establishes the relations linking the states of switches with the conversion functions. Afterwards, the presented method gives the inverse relations which constitute the sequential part of the converter control. The turn-on and the turn-off sequences are designed by considering the on-line wished level conversions. This general method enhances the idea that a converter functionnality must be defined by its structure and its control. Cet article propose une méthode originale pour définir la séquence de commande d'un convertisseur à partir de la fonction de conversion globalement souhaitée. Les auteurs procèdent d'abord à une analyse mathématique précise des relations qui existent entre les états des interrupteurs et les fonctions de conversion obtenues. À partir de cette analyse, la méthode developpée permet d'établir systématiquement les relations inverses qui constituent alors le module séquentiel de la commande rapprochée du convertisseur. Les ordres d'ouverture et de fermeture des interrupteurs sont élaborés en considérant à tout instant les niveaux de conversion souhaités pour les grandeurs électriques. Cette méthode générale renforce l'idée que la fonction remplie par un convertisseur moderne doit être définie à la fois par sa structure et sa commande.

  10. Insertable fluid flow passage bridgepiece and method

    DOEpatents

    Jones, Daniel O.

    2000-01-01

    A fluid flow passage bridgepiece for insertion into an open-face fluid flow channel of a fluid flow plate is provided. The bridgepiece provides a sealed passage from a columnar fluid flow manifold to the flow channel, thereby preventing undesirable leakage into and out of the columnar fluid flow manifold. When deployed in the various fluid flow plates that are used in a Proton Exchange Membrane (PEM) fuel cell, bridgepieces of this invention prevent mixing of reactant gases, leakage of coolant or humidification water, and occlusion of the fluid flow channel by gasket material. The invention also provides a fluid flow plate assembly including an insertable bridgepiece, a fluid flow plate adapted for use with an insertable bridgepiece, and a method of manufacturing a fluid flow plate with an insertable fluid flow passage bridgepiece.

  11. Étude analytique des perturbations solaires des satellites d'Uranus.

    NASA Astrophysics Data System (ADS)

    Dumoulin, C.; Laskar, J.

    1990-12-01

    Ce travail s'insère dans le cadre de la General Uranian Satellites Theory de J. Laskar (1986) et Laskar et Jacobson (1987), qui donne une solution analytique du mouvement des cinq principaux satellites d'Uranus, incluant les perturbations mutuelles et la perturbation due à l'aplatissement de la planète. Les perturbations solaires dont il n'avaient pas été tenu compte dans cette étude ont été calculées pour tous les éléments orbitaux de chaque satellite.

  12. Relations de Dispersion et Diffusion des Glueballs et des Mesons dans la Theorie de Jauge U(1)(2+1) Compacte

    NASA Astrophysics Data System (ADS)

    Ahmed, Chaara El Mouez

    Nous avons etudie les relations de dispersion et la diffusion des glueballs et des mesons dans le modele U(1)_{2+1} compact. Ce modele a ete souvent utilise comme un simple modele de la chromodynamique quantique (QCD), parce qu'il possede le confinement ainsi que les etats de glueballs. Par contre, sa structure mathematique est beaucoup plus simple que la QCD. Notre methode consiste a diagonaliser l'Hamiltonien de ce modele dans une base appropriee de graphes et sur reseau impulsion, afin de generer les relations de dispersion des glueballs et des mesons. Pour la diffusion, nous avons utilise la methode dependante du temps pour calculer la matrice S et la section efficace de diffusion des glueballs et des mesons. Les divers resultats obtenus semblent etre en accord avec les travaux anterieurs de Hakim, Alessandrini et al., Irving et al., qui eux, utilisent plutot la theorie des perturbations en couplage fort, et travaillent sur un reseau espace-temps.

  13. Fluid pathways in subduction zones

    NASA Astrophysics Data System (ADS)

    Spiegelman, M. W.; van Keken, P. E.; Hacker, B. R.

    2009-12-01

    A large amount of water captured in the oceanic crust and mantle is recycled in subduction zones. Upon compaction and heating most fluids are expelled, but a significant amount of water can be carried in hydrated mineral phases and point defects. While the qualitative role of volatiles and dehydration reactions is well appreciated in the mechanisms for intermediate depth seismicity, mantle wedge melting and arc volcanism, the quantitative details of the metamorphic reactions and the pathways of fluids and melts in the slab are poorly understood. We provide finite element models, combined with thermodynamic and mineralogical constraints, to estimate the water release and migration from the subducting slab to overlying arc. We use models from a selection of warm (e.g., Cascadia), cold (Central Honshu) and intermediate (Nicaragua) subduction zones, using slab geometries constrained from seismological observations. The fluid release is predicted from the breakdown of hydrated phases in sediments, oceanic crust and slab mantle. We use newly developed high resolution models for the flow of these released fluids that take into account permeability and compaction pressures. While the detailed structure depends on the chosen rheology and permeability, we find that for reasonable assumptions of permeability, a significant amount of fluids can travel through the wedge along nearly vertical pathways at rates and paths, consistent with geochronological and geochemical constraints. For models considered to date, we find that the principal source of fluids that feed the wedge come from the hydrated oceanic crust and particularly the hydrated slab mantle. Fluids released from the sediments and shallow crust, tend to travel along high permeability zones in the subducting slab before being released to hydrate the cold corner of subduction zones, suggesting that the cold and hydrated forearc region that is imaged in many subduction zones is maintained by an active hydrological cycle

  14. La planification préalable des soins pour les patients en pédiatrie

    PubMed Central

    2008-01-01

    RÉSUMÉ Les progrès médicaux et technologiques ont permis d’ac-croître les taux de survie et d’améliorer la qualité de vie des nourrissons, des enfants et des adolescents ayant des maladies chroniques mettant la vie en danger. La planifi-cation préalable des soins inclut le processus relié aux discussions sur les traitements essentiels au maintien de la survie et la détermination des objectifs des soins de longue durée. Les dispensateurs de soins pédiatriques ont l’obligation éthique d’assimiler cet aspect des soins médicaux. Le présent document de principes vise à aider les dispensateurs de soins à discuter de la planification préalable des soins des patients pédiatriques dans diverses situations. La planification préalable des soins exige des communications efficaces afin de clarifier les objectifs des soins et de s’entendre sur les traitements pertinents ou non pour réaliser ces objectifs, y compris les mesures de réanimation et les mesures palliatives.

  15. Combustion, Complex Fluids, and Fluid Physics Experiments on the ISS

    NASA Technical Reports Server (NTRS)

    Motil, Brian; Urban, David

    2012-01-01

    From the very early days of human spaceflight, NASA has been conducting experiments in space to understand the effect of weightlessness on physical and chemically reacting systems. NASA Glenn Research Center (GRC) in Cleveland, Ohio has been at the forefront of this research looking at both fundamental studies in microgravity as well as experiments targeted at reducing the risks to long duration human missions to the moon, Mars, and beyond. In the current International Space Station (ISS) era, we now have an orbiting laboratory that provides the highly desired condition of long-duration microgravity. This allows continuous and interactive research similar to Earth-based laboratories. Because of these capabilities, the ISS is an indispensible laboratory for low gravity research. NASA GRC has been actively involved in developing and operating facilities and experiments on the ISS since the beginning of a permanent human presence on November 2, 2000. As the lead Center for combustion, complex fluids, and fluid physics; GRC has led the successful implementation of the Combustion Integrated Rack (CIR) and the Fluids Integrated Rack (FIR) as well as the continued use of other facilities on the ISS. These facilities have supported combustion experiments in fundamental droplet combustion; fire detection; fire extinguishment; soot phenomena; flame liftoff and stability; and material flammability. The fluids experiments have studied capillary flow; magneto-rheological fluids; colloidal systems; extensional rheology; pool and nucleate boiling phenomena. In this paper, we provide an overview of the experiments conducted on the ISS over the past 12 years.

  16. Complex fluid-fluid interfaces: rheology and structure.

    PubMed

    Fuller, Gerald G; Vermant, Jan

    2012-01-01

    Complex fluid-fluid interfaces are common to living systems, foods, personal products, and the environment. They occur wherever surface-active molecules and particles collect at fluid interfaces and render them nonlinear in their response to flow and deformation. When this occurs, the interfaces acquire a complex microstructure that must be interrogated. Interfacial rheological material properties must be measured to appreciate their role in such varied processes as lung function, cell division, and foam and emulsion stability. This review presents the methods that have been devised to determine the microstructure of complex fluid-fluid interfaces. Complex interfacial microstructure leads to rheological complexity. This behavior is often responsible for stabilizing interfacial systems such as foams and emulsions, and it can also have a profound influence on wetting/dewetting dynamics. Interfacial rheological characterization relies on the development of tools with the sensitivity to respond to small surface stresses in a way that isolates them from bulk stresses. This development is relatively recent, and reviews of methods for both shear and dilatational measurements are offered here.

  17. Polyphase evolution of the Chaîne des Matheux frontal thrust (Haiti)

    NASA Astrophysics Data System (ADS)

    Wessels, Richard; Ellouz-Zimmermann, Nadine; Rosenberg, Claudio; Bellahsen, Nicolas; Hamon, Youri; Deschamps, Remy; Battani, Anne; Leroy, Sylvie; Momplaisir, Roberte

    2016-04-01

    The NW - SE trending Haitian fold-and-thrust belt (HFTB) is located in the western part of the Caribbean island of Hispaniola. It covers the suture between the Cretaceous Caribbean island arc in the north and the Late Cretaceous thickened oceanic crust in the south. The HFTB is bounded to the north and south by the left-lateral Septentrional (SFZ) and Enriquillo-Plantain Garden (EPGFZ) fault zones, respectively. Compressional deformation on the HFTB commenced as early as Eocene times. It was followed by transpressional deformation from the early Miocene onwards, with in sequence progressive stacking of thrust sheets towards the SW. Seismicity at the junction between the HFTB and the EPGFZ is recorded by the 12 January 2010 Mw 7.0 earthquake. Surface mapping did not reveal a rupture, as the main activity occurred on the steep NNW dipping oblique transpressional Léogâne fault, while aftershocks documented motion on a shallow SW dipping thrust segment. The structural style of deformation of the HFTB, either the stacking of thrust sheets on basement heterogeneities or basement-involved thrusting, has not been studied in detail. Also lacking are conceptual models addressing the amount of convergence between the northern and southern domains, and describing how convergence was accommodated. To address these problems we conducted a detailed fieldwork on the southernmost thrust sheet, known as the Chaîne des Matheux front. Using stratigraphy, geological mapping, cross sections, kinematic fault slip data, analysis of mineralizations and fluid inclusions, and geochemical analysis of fluid seeps, we decipher the evolution of this anticlinal structure. Stratigraphic data reveal stable Eocene platform sedimentation over the whole region, which preceded deepening of the basin throughout Oligocene and early Miocene times. A diachronous evolution is evident from the middle Miocene onwards. The NE flank displays a shallowing upwards trend and clastic sedimentation, while the

  18. Catalog Production for the DES Blind Cosmology Challenge

    NASA Astrophysics Data System (ADS)

    Busha, Michael T.; Wechsler, R. H.; Becker, M. R.; Erickson, B.; Evrard, A. E.

    2013-01-01

    The Blind Cosmology Challenge (BCC) is an effort by the Dark Energy Survey (DES) to test analysis tools for extracting cosmological information using a set of detailed synthetic galaxy catalogs. Here, we describe the creation of these synthetic sky catalogs based on requirements of the optical (DES) and the near-IR VISTA Hemisphere Survey, producing catalogs covering a quarter of the sky to z ˜ 2, with sources complete to r ˜ 25. Starting with a nested set of lightcone outputs of large, N-body simulation, galaxies are assigned to the dark matter distribution using an empirical algorithm that is tunable to match observed evolution of low-order galaxy population properties (counts and spatial clustering) in luminosity-color-density space. Galaxies are lensed by matter along the line of sight (including magnification, shape distortion, and multiple images), using a new algorithm that calculates shear with 3.22 arcsec resolution at galaxy positions in the full catalog. The catalog is well suited to support DES+VISTA joint studies of galaxy clustering, groups and clusters of galaxies, and gravitational lensing, and we highlight their application to the ongoing DES BBCC. Catalogs include ˜320 million galaxies and ˜150 million stars, with realistic colors, shapes and photometric errors. Using the expected DES photometric errors, three independent photometric redshift codes are run on the catalog, two of which produce full probability distributions. The synthetic observable catalog includes object position, magnitudes in the DES and VISTA bands, photometric errors, photometric redshifts, size, ellipticity, for each of ˜ 500 million objects. The galaxy distribution is additionally masked appropriately for the 5000 square degree DES footprint, including the impact of bright stars. In addition, we offer separate catalogs with magnitudes for additional existing and planned surveys, including SDSS, CFHTLS, HSC, LSST, and Euclid.

  19. De l'importance des orbites periodiques: Detection et applications

    NASA Astrophysics Data System (ADS)

    Doyon, Bernard

    L'ensemble des Orbites Periodiques Instables (OPIs) d'un systeme chaotique est intimement relie a ses proprietes dynamiques. A partir de l'ensemble (en principe infini) d'OPIs cachees dans l'espace des phases, on peut obtenir des quantites dynamiques importantes telles les exposants de Lyapunov, la mesure invariante, l'entropie topologique et la dimension fractale. En chaos quantique (i.e. l'etude de systemes quantiques qui ont un equivalent chaotique dans la limite classique), ces memes OPIs permettent de faire le pont entre le comportement classique et quantique de systemes non-integrables. La localisation de ces cycles fondamentaux est un probleme complexe. Cette these aborde dans un premier temps le probleme de la detection des OPIs dans les systemes chaotiques. Une etude comparative de deux algorithmes recents est presentee. Nous approfondissons ces deux methodes afin de les utiliser sur differents systemes dont des flots continus dissipatifs et conservatifs. Une analyse du taux de convergence des algorithmes est aussi realisee afin de degager les forces et les limites de ces schemes numeriques. Les methodes de detection que nous utilisons reposent sur une transformation particuliere de la dynamique initiale. Cette astuce nous a inspire une methode alternative pour cibler et stabiliser une orbite periodique quelconque dans un systeme chaotique. Le ciblage est en general combine aux methodes de controle pour stabiliser rapidement un cycle donne. En general, il faut connaitre la position et la stabilite du cycle en question. La nouvelle methode de ciblage que nous presentons ne demande pas de connaitre a priori la position et la stabilite des orbites periodiques. Elle pourrait etre un outil complementaire aux methodes de ciblage et de controle actuelles.

  20. Evaluation du niveau de connaissance des patients sur la gestion du traitement par les antis vitamines K dans le service de cardiologie de Ouagadougou

    PubMed Central

    Samadoulougou, André; Temoua Naibe, Dangwé; Mandi, Germain; Yameogo, Relwendé Aristide; Kabore, Elisé; Millogo, Georges; Yameogo, Nobila Valentin; Kologo, Jonas Koudougou; Thiam/Tall, Anna; Toguyeni, Boubacar Jean Yves; Zabsonre, Patrice

    2014-01-01

    Introduction Les antivitamines K (AVK), traitement anticoagulant oral le plus largement prescrit, posent un réel problème de santé publique du fait de leur risque iatrogène. L'objectif de cette étude était de préciser le niveau de connaissance des patients sur la gestion de leur traitement par les AVK. Méthodes Il s'est agi d'une enquête transversale descriptive réalisée au CHU-Yalgado Ouédraogo, sur une période de 03 mois : du 1er mars au 31 mai 2012. Un questionnaire a été administré aux patients bénéficiant d'un traitement AVK depuis au moins un mois. Résultats Soixante-dix patients ont été inclus dans l'étude dont 30 hommes. L'âge moyen était de 49 ans ± 16 ans. Les cardiopathies et la maladie thromboembolique veineuse justifiant l'institution du traitement AVK étaient retrouvées respectivement dans 58,6% et 41,4% des cas. Le nom de l'AVK et la raison exacte du traitement étaient connus respectivement dans 91,4% et 67,1% des cas. Plus de la moitié des patients (68,6%) savaient que les AVK rendaient le sang plus fluide. Quarante-six patients (65,7%) citaient l'INR comme examen biologique de surveillance du traitement et seulement 28 patients (40%) connaissaient les valeurs cibles. La majorité des patients ne connaissait pas les risques encourus en cas de surdosage (72,8%) et de sous-dosage (71,4%). Une automédication par anti-inflammatoire non stéroïdien était signalée par 18 patients (25,7%). Les choux (74,3%) et la laitue (62,9%), aliments à consommer avec modération, étaient les plus cités. Conclusion Les connaissances des patients sur la gestion des AVK étaient fragmentaires et insuffisantes pour assurer la sécurité et l'efficacité du traitement. La création d'un programme d'éducation thérapeutique sur les AVK s'avère alors nécessaire. PMID:25870741

  1. Dynamics of particle clusters at fluid/fluid interfaces

    NASA Astrophysics Data System (ADS)

    Madhavan, Srinath; Minev, Peter; Nandakumar, Krishnaswamy

    2009-11-01

    This talk is oriented toward research that describes the hydrodynamics of dense (relative to the lower fluid in a gravitational field) rigid particles at fluid-fluid interfaces through Direct Numerical Simulations (DNS). Understanding the factors that control the formation and stability of the complex rag layer (typically encountered during oil-water separation) is a motivation for the current study. The fundamental aspects of the problem at hand bear a connection with the formation of tight clusters of floating particles. Strong capillary forces are thought to promote this behavior. One of the challenges toward realizing the same in a numerical simulation is the implementation of a physically realistic boundary condition for the three phase moving contact line (MCL). To this end, we implement the recently proposed continuum form of the Generalized Navier Boundary Condition (Gerbeau and Lelievre, 2009) in a levelset and fictitious-domain based finite-element scheme and demonstrate its usefulness and accuracy through case studies.

  2. Le role du phytoplancton de petite taille (<20 mum) dans les variations des proprietes optiques des eaux du Saint-Laurent

    NASA Astrophysics Data System (ADS)

    Mas, Sebastien

    Les mesures satellitaires de couleur des oceans sont largement determinees par les proprietes optiques inherentes (IOPs) des eaux de surface. D'autre part, le phytoplancton de petite taille (<20 mum) est le plus souvent dominant dans les oceans, et peut donc etre une source importante de variation des IOPs dans les oceans. Dans ce contexte, le but principal de ce doctorat etait de definir l'impact du phytoplancton (<20 mum) sur les variations des proprietes optiques de l'Estuaire et du Golfe du Saint-Laurent (Canada). Afin d'atteindre cet objectif, il etait necessaire de determiner en milieu controle les facteurs de variabilite des proprietes optiques cellulaires et des IOPs du phytoplancton (<20 mum) des eaux du Saint-Laurent, et d'evaluer la contribution du phytoplancton (<20 mum) aux proprietes optiques totales des eaux du Saint-Laurent. Des experiences en laboratoire ont montre que les variations des proprietes optiques des cellules phytoplanctoniques soumises a un cycle jour-nuit, ainsi qu'a des changements concomitants d'intensite lumineuse, peuvent contribuer significativement a la variabilite des proprietes optiques observee en milieu naturel. D'autres experiences ont, quant a elles, mis en evidence que les variations des proprietes optiques des cellules phytoplanctoniques dues aux phases de croissance peuvent alterer les IOPs des oceans, particulierement pendant les periodes de floraison. De plus, la presence de bacteries et de particules detritiques peut egalement affecter la variabilite des IOPs totales, notamment la diffusion. Au printemps, dans l'Estuaire et le Golfe du Saint-Laurent, la contribution du phytoplancton <20 mum aux IOPs presentait des differences regionales evidentes pour les proprietes d'absorption et de diffusion. En plus de la variabilite spatiale, les proprietes optiques cellulaires presentaient des variations journalieres, et ce particulierement pour le picophytoplancton. Enfin, la plupart des differences observees dans les

  3. Fluid Behavior and Fluid-Solid Interactions in Nanoporous Media

    NASA Astrophysics Data System (ADS)

    Xu, H.

    2015-12-01

    Although shale oil/gas production in the US has increased exponentially, the low energy recovery is a daunting problem needed to be solved for its sustainability and continued growth, especially in light of the recent oil/gas price decline. This is apparently related to the small porosity (a few to a few hundred nm) and low permeability (10-16-10-20 m2) of tight shale formations. The fundamental question lies in the anomalous behavior of fluids in nanopores due to confinement effects, which, however, remains poorly understood. In this study, we combined experimental characterization and observations, particularly using small-angle neutron scattering (SANS), with pore-scale modeling using lattice Boltzmann method (LBM), to examine the fluid behavior and fluid-solid interactions in nanopores at reservoir conditions. Experimentally, we characterized the compositions and microstructures of a shale sample from Wolfcamp, Texas, using a variety of analytical techniques. Our analyses reveal that the shale sample is made of organic-matter (OM)-lean and OM-rich layers that exhibit different chemical and mineral compositions, and microstructural characteristics. Using the hydrostatic pressure system and gas-mixing setup we developed, in-situ SANS measurements were conducted at pressures up to 20 kpsi on shale samples imbibed with water or water-methane solutions. The obtained results indicate that capillary effect plays a significant role in fluid-nanopore interactions and the associated changes in nanopore structures vary with pore size and pressure. Computationally, we performed LBM modeling to simulate the flow behavior of methane in kerogen nanoporous structure. The correction factor, which is the ratio of apparent permeability to intrinsic permeability, was calculated. Our results show that the correction factor is always greater than one (non-continuum/non-Darcy effects) and increases with decreasing nanopore size, intrinsic permeability and pressure. Hence, the

  4. Combustion, Complex Fluids, and Fluid Physics Experiments on the ISS

    NASA Technical Reports Server (NTRS)

    Motil, Brian; Urban, David

    2012-01-01

    From the very first days of human spaceflight, NASA has been conducting experiments in space to understand the effect of weightlessness on physical and chemically reacting systems. NASA Glenn Research Center (GRC) in Cleveland, Ohio has been at the forefront of this research looking at both fundamental studies in microgravity as well as experiments targeted at reducing the risks to long duration human missions to the moon, Mars, and beyond. In the current International Space Station (ISS) era, we now have an orbiting laboratory that provides the highly desired condition of long-duration microgravity. This allows continuous and interactive research similar to Earth-based laboratories. Because of these capabilities, the ISS is an indispensible laboratory for low gravity research. NASA GRC has been actively involved in developing and operating facilities and experiments on the ISS since the beginning of a permanent human presence on November 2, 2000. As the lead Center both Combustion, Fluid Physics, and Acceleration Measurement GRC has led the successful implementation of an Acceleration Measurement systems, the Combustion Integrated Rack (CIR), the Fluids Integrated Rack (FIR) as well as the continued use of other facilities on the ISS. These facilities have supported combustion experiments in fundamental droplet combustion fire detection fire extinguishment soot phenomena flame liftoff and stability and material flammability. The fluids experiments have studied capillary flow magneto-rheological fluids colloidal systems extensional rheology pool and nucleate boiling phenomena. In this paper, we provide an overview of the experiments conducted on the ISS over the past 12 years. We also provide a look to the future development. Experiments presented in combustion include areas such as droplet combustion, gaseous diffusion flames, solid fuels, premixed flame studies, fire safety, and super critical oxidation processes. In fluid physics, experiments are discussed in

  5. Interdisciplinary Research Programs in Geophysical Fluid Dynamics

    DTIC Science & Technology

    2007-09-30

    scientific disciplines that deal with the dynamics of stratified fluids, rotating fluids, fluid with phase changes and non-Newtonian fluids. To formulate...clearing-house for the mathematical, experimental and computational techniques which serve astrophysics, climate science, geodynamics, meteorology and... Zika , Physical Oceanography, University of New South Wales, “The stability of cascading flows”. RESULTS The Principal Lectures and Fellows

  6. Pitch-catch only ultrasonic fluid densitometer

    DOEpatents

    Greenwood, M.S.; Harris, R.V.

    1999-03-23

    The present invention is an ultrasonic fluid densitometer that uses a material wedge and pitch-catch only ultrasonic transducers for transmitting and receiving ultrasonic signals internally reflected within the material wedge. Density of a fluid is determined by immersing the wedge into the fluid and measuring reflection of ultrasound at the wedge-fluid interface. 6 figs.

  7. Pitch-catch only ultrasonic fluid densitometer

    DOEpatents

    Greenwood, Margaret S.; Harris, Robert V.

    1999-01-01

    The present invention is an ultrasonic fluid densitometer that uses a material wedge and pitch-catch only ultrasonic transducers for transmitting and receiving ultrasonic signals internally reflected within the material wedge. Density of a fluid is determined by immersing the wedge into the fluid and measuring reflection of ultrasound at the wedge-fluid interface.

  8. 7 CFR 2902.41 - Metalworking fluids.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... operations such as cutting, drilling, grinding, machining, and tapping. (2) Metalworking fluids for which... 7 Agriculture 15 2010-01-01 2010-01-01 false Metalworking fluids. 2902.41 Section 2902.41... Items § 2902.41 Metalworking fluids. (a) Definition. (1) Fluids that are designed to provide...

  9. Drug Testing in Oral Fluid

    PubMed Central

    Drummer, Olaf H

    2006-01-01

    Over the last decade there have been considerable developments in the use of oral fluid (saliva) for drug testing. Oral fluid can provide a quick and non-invasive specimen for drug testing. However, its collection may be thwarted by lack of available fluid due to a range of physiological factors, including drug use itself. Food and techniques designed to stimulate production of oral fluid can also affect the concentration of drugs. Current applications are mainly focused on drugs of abuse testing in employees at workplaces where drug use has safety implications, in drivers of vehicles at the roadside and in other situations where drug impairment is suspected. Testing has included alcohol (ethanol) and a range of clinical tests eg antibodies to HIV, therapeutic drugs and steroids. Its main application has been for testing for drugs of abuse such as the amphetamines, cocaine and metabolites, opioids such as morphine, methadone and heroin, and for cannabis. Oral fluid concentrations of basic drugs such as the amphetamines, cocaine and some opioids are similar or higher than those in plasma. Tetrahydrocannabinol (THC), the major species present from cannabis use, displays similar concentrations in oral fluid compared to blood in the elimination phase. However, there is significant local absorption of the drug in the oral cavity which increases the concentrations for a period after use of drug. Depot effects occur for other drugs introduced into the body that allow local absorption, such as smoking of tobacco (nicotine), cocaine, amphetamines, or use of sub-lingual buprenorphine. Screening techniques are usually an adaptation of those used in other specimens, with an emphasis on the parent drug since this is usually the dominant species present in oral fluid. Confirmatory techniques are largely based on mass spectrometry (MS) with an emphasis on Liquid Chromatography-Mass Spectrometry (LC-MS), due to low sample volumes and the low detection limits required. Drug testing

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

    NASA Astrophysics Data System (ADS)

    Biskri, Djallel Eddine

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

  11. Third Microgravity Fluid Physics Conference

    NASA Technical Reports Server (NTRS)

    1996-01-01

    The conference's purpose was to inform the fluid physics community of research opportunities in reduced-gravity fluid physics, present the status of the existing and planned reduced gravity fluid physics research programs, and inform participants of the upcoming NASA Research Announcement in this area. The plenary sessions provided an overview of the Microgravity Fluid Physics Program, present and future areas of emphasis, information on NASA's ground-based and space-based flight research facilities-especially use of the International Space Station, and the process by which future investigators enter the program. An international forum offered participants an opportunity to hear from Russian speakers about their microgravity research programs. Three keynote speakers provided broad technical overviews on the history and future development of the moon and on multiphase flow and complex fluids research. One keynote paper and an extended abstract are included in the proceedings. One hundred and thirty-two technical papers were presented in 28 sessions. Presenters briefed their peers on the scientific results of their ground-based and flight research. One hundred and twenty-two papers are included here.

  12. DEVELOPMENT OF NEW DRILLING FLUIDS

    SciTech Connect

    David B. Burnett

    2003-08-01

    The goal of the project has been to develop new types of drill-in fluids (DIFs) and completion fluids (CFs) for use in natural gas reservoirs. Phase 1 of the project was a 24-month study to develop the concept of advanced type of fluids usable in well completions. Phase 1 tested this concept and created a kinetic mathematical model to accurately track the fluid's behavior under downhole conditions. Phase 2 includes tests of the new materials and practices. Work includes the preparation of new materials and the deployment of the new fluids and new practices to the field. The project addresses the special problem of formation damage issues related to the use of CFs and DIFs in open hole horizontal well completions. The concept of a ''removable filtercake'' has, as its basis, a mechanism to initiate or trigger the removal process. Our approach to developing such a mechanism is to identify the components of the filtercake and measure the change in the characteristics of these components when certain cleanup (filtercake removal) techniques are employed.

  13. Ultracentrifuge for separating fluid mixtures

    DOEpatents

    Lowry, Ralph A.

    1976-01-01

    1. A centrifuge for the separation of fluid mixtures having light and heavy fractions comprising a cylindrical rotor, disc type end-plugs closing the ends of the rotor, means for mounting said rotor for rotation about its cylindrical axis, a housing member enclosing the rotor, a vacuum chamber in said housing about the central portion of the rotor, a collection chamber at each end of the housing, the innermost side of which is substantially formed by the outer face of the end-plug, means for preventing flow of the fluid from the collection chambers to said vacuum chamber, at least one of said end-plugs having a plurality of holes therethrough communicating between the collection chamber adjacent thereto and the inside of the rotor to induce countercurrent flow of the fluid in the centrifuge, means for feeding fluid to be processed into the centrifuge, means communicating with the collection chambers to extract the light and heavy separated fractions of the fluid, and means for rotating the rotor.

  14. Anthropometric changes and fluid shifts

    NASA Technical Reports Server (NTRS)

    Thornton, W. E.; Hoffler, G. W.; Rummel, J. A.

    1974-01-01

    Several observations of body size, shape, posture, and configuration were made to document changes resulting from direct effects of weightlessness during the Skylab 4 mission. After the crewmen were placed in orbit, a number of anatomical and anthropometric changes occurred including a straightening of the thoracolumbar spine, a general decrease in truncal girth, and an increase in height. By the time of the earliest in-flight measurement on mission day 3, all crewmen had lost more than two liters of extravascular fluid from the calf and thigh. The puffy facies, the bird legs effect, the engorgement of upper body veins, and the reduced volume of lower body veins were all documented with photographs. Center-of-mass measurements confirmed a fluid shift cephalad. This shift remained throughout the mission until recovery, when a sharp reversal occurred; a major portion of the reversal was completed in a few hours. The anatomical changes are of considerable scientific interest and of import to the human factors design engineer, but the shifts of blood and extravascular fluid are of more consequence. It is hypothesized that the driving force for the fluid shift is the intrinsic and unopposed lower limb elasticity that forces venous blood and then other fluid cephalad.

  15. Fluid processes in subduction zones.

    PubMed

    Peacock, S A

    1990-04-20

    Fluids play a critical role in subduction zones and arc magmatism. At shallow levels in subduction zones (<40 kilometers depth), expulsion of large volumes of pore waters and CH(4)-H(2)O fluids produced by diagenetic and low-grade metamorphic reactions affect the thermal and rheological evolution of the accretionary prism and provide nutrients for deep-sea biological communities. At greater depths, H(2)O and CO(2) released by metamorphic reactions in the subducting oceanic crust may alter the bulk composition in the overlying mantle wedge and trigger partial melting reactions. The location and conse-quences of fluid production in subduction zones can be constrained by consideration of phase diagrams for relevant bulk compositions in conjunction with fluid and rock pressure-temperature-time paths predicted by numerical heat-transfer models. Partial melting of subducting, amphibole-bearing oceanic crust is predicted only within several tens of million years of the initiation of subduction in young oceanic lithosphere. In cooler subduction zones, partial melting appears to occur primarily in the overlying mantle wedge as a result of fluid infiltration.

  16. Working fluids for electrical generating plants

    SciTech Connect

    Loomis, R.G.

    1984-08-28

    Halides of tungsten and molybdenum are described for use as working fluids in power plants. Specifically, tungsten pentachloride, tungsten hexachloride, molybdenum hexafluoride and molybdenum hexachloride are used as working fluids in power plants. These working fluids can be used alone in a single cycle. However, they are preferably used in one or two loops of a binary system. The working fluids can be used in combination with other known working fluids in a binary system. Specifically useful, working fluids would include water-Hg, aluminum iodide, water, and nitrogen tetroxide. The use of the novel boiler fluids of the present invention provide numerous advantages, particularly, improved efficiency.

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

    NASA Astrophysics Data System (ADS)

    Khettabi, Riad

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

  18. Multiple fluid-filled bone metastases.

    PubMed

    Frenzel, Laurent; Javier, Rose-Marie; Eichler, Francoise; Zollner, Goerg; Sibilia, Jean

    2010-03-01

    Bone metastases are usually seen on imaging studies as lytic lesions and less often as sclerotic or mixed lesions. We report an exceedingly unusual case of breast cancer identified after magnetic resonance imaging showed bone metastases with fluid-fluid levels in the spine and sacrum. Bone images containing fluid-fluid levels are usually solitary abnormalities produced by aneurismal bone cysts. The fluid-fluid level is due to bleeding within the tumor followed by layering of the blood components based on density differences. Only two other cases of bone metastases with multiple fluid-fluid levels have been reported. Although fluid-fluid levels are exceedingly rare, clinicians should be aware that they might indicate a malignancy, particularly when they are multiple.

  19. Electronic Messaging for the 90s (Les Messageries Electroniques des Annees 90)

    DTIC Science & Technology

    1993-05-01

    cle une importance considdrable, au cette inddpendance support/contenti ntm xiste pas. Au niveati des Etats, des administrations, des entreprises ... financi ~res nature de lVinformation sont tr~s ddpendantes de sa entre detix points tr~s dloignds, tels que New York et chaine de traitement. qui induit tout...principe essenticl de entreprise oti du monde entier. RETRAITABILITE de l’information tout consommateur petit A son tour devenir producteur 1. DES ESPACES

  20. Cue Integration in Dynamic Decision Marking (Integration des indices dans la Prise de Decision Dynamique)

    DTIC Science & Technology

    2010-07-01

    environnements complexes et dynamiques. La nature complexe et dynamique de differents types d’operations (p. ex., les operations basees sur les...destinees a preparer les commandants et le personnel des etats- majors des Forces canadiennes (FC) a prendre des decisions dans des environnements ...Ia prise de decisions dans les environnements complexes et dynamiques est habituellement designee sous le nom de prise de decisions dynamique (POD

  1. Theoretical prediction of multiple fluid-fluid transitions in monocomponent fluids

    NASA Astrophysics Data System (ADS)

    Cervantes, L. A.; Benavides, A. L.; del Río, F.

    2007-02-01

    The authors use the analytical equation of state obtained by the discrete perturbation theory [A. L. Benavides and A. Gil-Villegas, Mol. Phys. 97, 1225 (1999)] to study the phase diagram of fluids with discrete spherical potentials formed by a repulsive square-shoulder plus an attractive square-well interaction (SS+SW). This interaction is characterized by the usual energy and size parameters plus three dimensionless parameters: two of them measuring the widths of the SS and the SW and the third the relative height of the SS. The matter of interest is that, for certain values of the interaction parameters, the SS +SW systems exhibit more than one first-order fluid-fluid transition. The evidence that several real substances (such as water, phosphorus, carbon, and silica, among others) exhibit an extra liquid-liquid transition has drawn interest into the study of interactions responsible for this behavior. The simple SS +SW fluid is one of the systems that, in spite of being spherically symmetric, shows multiple fluid-fluid transitions. In this work the authors investigate systematically the effect on the phase diagram of varying the interaction parameters. The use of an analytical free-energy equation gives a clear thermodynamic picture of the emergence of different types of critical points, throwing new light on the phase behavior of these fluids and thus clarifying previous results obtained by other techniques. The interplay of attractive and repulsive forces with several scale lengths produces very rich phase diagrams, including cases with three critical points. The region of the interaction-parameter space where multiple critical points appear is mapped for various families of interactions.

  2. Fluid dynamics of bacterial turbulence.

    PubMed

    Dunkel, Jörn; Heidenreich, Sebastian; Drescher, Knut; Wensink, Henricus H; Bär, Markus; Goldstein, Raymond E

    2013-05-31

    Self-sustained turbulent structures have been observed in a wide range of living fluids, yet no quantitative theory exists to explain their properties. We report experiments on active turbulence in highly concentrated 3D suspensions of Bacillus subtilis and compare them with a minimal fourth-order vector-field theory for incompressible bacterial dynamics. Velocimetry of bacteria and surrounding fluid, determined by imaging cells and tracking colloidal tracers, yields consistent results for velocity statistics and correlations over 2 orders of magnitude in kinetic energy, revealing a decrease of fluid memory with increasing swimming activity and linear scaling between kinetic energy and enstrophy. The best-fit model allows for quantitative agreement with experimental data.

  3. RRM3 Fluid Management Device

    NASA Technical Reports Server (NTRS)

    Barfknecht, P.; Benson, D.; Boyle, R.; DeLee, C.; DiPirro, M.; Francis, J.; Li, X.; McGuire, J.; Mustafi, S.; Tuttle, J.; Whitehouse, P.

    2015-01-01

    The current development progress of the fluid management device (FMD) for the Robotic Resupply Mission 3 (RRM3) cryogen source Dewar is described. RRM3 is an on-orbit cryogenic transfer experiment payload for the International Space Station. The fluid management device is a key component of the source Dewar to ensure the ullage bubble is located away from the outlet during transfer. The FMD also facilitates demonstration of radio frequency mass gauging within the source Dewar. The preliminary design of the RRM3 FMD is a number of concentric cones of Mylar which maximizes the volume of liquid in contact with the FMD in the source Dewar. This paper describes the design of the fluid management device and progress of hardware development

  4. Vitamin D in Tear Fluid

    PubMed Central

    Lu, Xiaowen; Elizondo, Rodolfo A.; Nielsen, Rikke; Christensen, Erik I.; Yang, Jun; Hammock, Bruce D.; Watsky, Mitchell A.

    2015-01-01

    Purpose To determine the source(s) of vitamin D in tear fluid and examine the expression of the endocytic proteins and putative vitamin D transporters megalin and cubilin in lacrimal and Harderian glands. Methods Wild-type, heterozygous, and vitamin D receptor (VDR) knockout C57BL/6 mice were used, with a subset of knockout mice fed a replenishment diet for some studies. Mouse lacrimal and Harderian glands from each group were used to measure megalin and cubilin by RT-PCR, Western blot, and immunohistochemistry. New Zealand white rabbits were used to collect lacrimal and accessory gland fluid for vitamin D mass spectroscopy measurements. Results Ten-week-old knockout mice were significantly (P < 0.05) smaller than wild-type mice. Real-time PCR and Western blot showed decreased expression of megalin and cubilin in select VDR knockout mouse groups. Immunohistochemistry showed apical duct cell megalin staining and weaker megalin staining in VDR knockout mice compared with controls. Vitamin D2 was more prevalent in rabbit lacrimal and accessory gland fluid than vitamin D3, and greater amounts of Vitamin D2 were found in in tear fluid obtained directly from lacrimal and accessory glands as compared with plasma concentrations. Conclusions This is the first study to demonstrate the presence of megalin and cubilin in lacrimal and accessory glands responsible for producing tear fluid. The results strengthen the hypothesis that megalin and cubilin are likely involved in the secretory pathway of vitamin D into tear fluid by the duct cells. PMID:26348637

  5. Kinetic Theory and Fluid Dynamics

    NASA Astrophysics Data System (ADS)

    Sone, Yoshio

    This monograph gives a comprehensive description of the relationship and connections between kinetic theory and fluid dynamics, mainly for a time-independent problem in a general domain. Ambiguities in this relationship are clarified, and the incompleteness of classical fluid dynamics in describing the behavior of a gas in the continuum limit—recently reported as the ghost effect—is also discussed. The approach used in this work engages an audience of theoretical physicists, applied mathematicians, and engineers. By a systematic asymptotic analysis, fluid-dynamic-type equations and their associated boundary conditions that take into account the weak effect of gas rarefaction are derived from the Boltzmann system. Comprehensive information on the Knudsen-layer correction is also obtained. Equations and their boundary conditions are carefully classified depending on the physical context of problems. Applications are presented to various physically interesting phenomena, including flows induced by temperature fields, evaporation and condensation problems, examples of the ghost effect, and bifurcation of flows. Key features: * many applications and physical models of practical interest * experimental works such as the Knudsen compressor are examined to supplement theory * engineers will not be overwhelmed by sophisticated mathematical techniques * mathematicians will benefit from clarity of definitions and precise physical descriptions given in mathematical terms * appendices collect key derivations and formulas, important to the practitioner, but not easily found in the literature Kinetic Theory and Fluid Dynamics serves as a bridge for those working in different communities where kinetic theory or fluid dynamics is important: graduate students, researchers and practitioners in theoretical physics, applied mathematics, and various branches of engineering. The work can be used in graduate-level courses in fluid dynamics, gas dynamics, and kinetic theory; some parts

  6. Problemes en enseignement fonctionnel des langues (Problems in the Functional Teaching of Languages). Publication B-103.

    ERIC Educational Resources Information Center

    Alvarez, Gerardo, Ed.; Huot, Diane, Ed.

    Articles include: (1) "L'elaboration du materiel pedagogique pour des publics adultes" (The Elaboration of Teaching Materials for the Adult Public) by G. Painchaud-Leblanc, (2) "L'elaboration d'un programme d'etudes en francais langue seconde a partir des donnees recentes en didactique des langues" (The Elaboration of a Program…

  7. Influence Operations: Historical and Contemporary Dimensions (Les Dimensions Historiques et Contemporaines des Operations d’Influence)

    DTIC Science & Technology

    2007-07-31

    entendue dans l’ensemble du discours politique et militaire des praticiens asiatiques des guerres de petite envergure et des théoriciens soviétiques... dividend ” through a reduction of defence spending. Naturally, the latter would have an effect on the nature of the British defence establishment. The

  8. Fluid control in microfluidic devices using a fluid conveyance extension and an absorbent microfluidic flow modulator.

    PubMed

    Yuen, Po Ki

    2013-05-07

    This article presents a simple method for controlling fluid in microfluidic devices without the need for valves or pumps. A fluid conveyance extension is fluidly coupled to the enclosed outlet chamber of a microfluidic device. After a fluid is introduced into the microfluidic device and saturates the fluid conveyance extension, a fluid flow in the microfluidic device is generated by contacting an absorbent microfluidic flow modulator with the fluid conveyance extension to absorb the fluid from the fluid conveyance extension through capillary action. Since the fluid in the microfluidic device is fluidly coupled with the fluid conveyance extension and the fluid conveyance extension is fluidly coupled with the absorbent microfluidic flow modulator, the absorption rate of the absorbent microfluidic flow modulator, which is the rate at which the absorbent microfluidic flow modulator absorbs fluid, matches the fluid flow rate in the microfluidic device. Thus, the fluid flow rate in the microfluidic device is set by the absorption rate of the absorbent microfluidic flow modulator. Sheath flow and fluid switching applications are demonstrated using this simple fluid control method without the need for valves or pumps. Also, the ability to control the fluid flow rate in the microfluidic device is demonstrated using absorbent microfluidic flow modulators with various absorbent characteristics and dimensions.

  9. CT findings of a unicameral calcaneal bone cyst containing a fluid-fluid level.

    PubMed

    Gallagher, Thomas A; Lim-Dunham, Jennifer E; Vade, Aruna

    2007-03-01

    Calcaneal unicameral bone cysts often contain fluid, but rarely contain fluid-fluid levels. We present a case focusing on the CT findings of a large calcaneal bone cyst with a fluid-fluid level and a review of the literature.

  10. Unsteady fluid flow in smart material actuated fluid pumps

    NASA Astrophysics Data System (ADS)

    John, Shaju; Cadou, Christopher

    2005-05-01

    Smart materials' ability to deliver large block forces in a small package while operating at high frequencies makes them extremely attractive for converting electrical to mechanical power. This has led to the development of hybrid actuators consisting of co-located smart material actuated pumps and hydraulic cylinders that are connected by a set of fast-acting valves. The overall success of the hybrid concept hinges on the effectiveness of the coupling between the smart material and the fluid. This, in turn, is strongly dependent on the resistance to fluid flow in the device. This paper presents results from three-dimensional unsteady simulations of fluid flow in the pumping chamber of a prototype hybrid actuator powered by a piezo-electric stack. The results show that the forces associated with moving the fluid into and out of the pumping chamber already exceed 10% of the piezo stack blocked force at relatively low frequencies ~120 Hz and approach 40% of the blocked force at 800 Hz. This reduces the amplitude of the piston motion in such a way that the volume flow rate remains approximately constant above operating frequencies of 500 Hz while the efficiency of the pump decreases rapidly.

  11. Fluid-solid contact vessel having fluid distributors therein

    DOEpatents

    Jones, Jr., John B.

    1980-09-09

    Rectangularly-shaped fluid distributors for large diameter, vertical vessels include reinforcers for high heat operation, vertical sides with gas distributing orifices and overhanging, sloped roofs. Devices are provided for cleaning the orifices from a buildup of solid deposits resulting from the reactions in the vessel.

  12. Wellbottom fluid implosion treatment system

    DOEpatents

    Brieger, Emmet F.

    2001-01-01

    A system for inducing implosion shock forces on perforation traversing earth formations with fluid pressure where an implosion tool is selected relative to a shut in well pressure and a tubing pressure to have a large and small area piston relationship in a well tool so that at a predetermined tubing pressure the pistons move a sufficient distance to open an implosion valve which permits a sudden release of well fluid pressure into the tubing string and produces an implosion force on the perforations. A pressure gauge on the well tool records tubing pressure and well pressure as a function of time.

  13. Sideload vanes for fluid pump

    NASA Technical Reports Server (NTRS)

    Erler, Scott R. (Inventor); Dills, Michael H. (Inventor); Rodriguez, Jose L. (Inventor); Tepool, John Eric (Inventor)

    2010-01-01

    A fluid pump assembly includes a rotatable component that can be rotated about an axis and a static vane assembly located adjacent to the rotatable component. The static vane assembly includes a circumferential surface axially spaced from the rotatable component, and one or more vanes extending from the circumferential surface toward the rotatable component. The one or more vanes are configured to produce a radial load on the rotatable component when the rotatable component is rotating about the axis and a fluid is present between the static vane assembly and the rotatable component.

  14. Transport coefficients of gluonic fluid

    SciTech Connect

    Das, Santosh K.; Alam, Jan-e

    2011-06-01

    The shear ({eta}) and bulk ({zeta}) viscous coefficients have been evaluated for a gluonic fluid. The elastic, gg{yields}gg and the inelastic, number nonconserving, gg{yields}ggg processes have been considered as the dominant perturbative processes in evaluating the viscous coefficients to entropy density (s) ratios. Recently the processes: gg{yields}ggg has been revisited and a correction to the widely used Gunion-Bertsch (GB) formula has been obtained. The {eta} and {zeta} have been evaluated for gluonic fluid with the formula recently derived. At large {alpha}{sub s} the value of {eta}/s approaches its lower bound, {approx}1/4{pi}.

  15. Magnetocaloric pump. [for cryogenic fluids

    NASA Technical Reports Server (NTRS)

    Brown, G. V. (Inventor)

    1974-01-01

    A vessel having inlet and outlet valves is disposed in a container with a fluid to be pumped which may be evolved from a liquid in the container below the vessel. A magnetocaloric substance is disposed in the vessel and causes fluid vapor in the vessel to expand and be expelled through the outlet valve. Vapor is drawn in through the inlet valve as the substance cools. The inlet valves may be one-way check valves or may be solenoid valves energized at appropriate times by timing circutis. A timer controlled heating element may also be disposed in the vessel to operate in conjunction with the magnetic field.

  16. Interfacial instabilities in vibrated fluids

    NASA Astrophysics Data System (ADS)

    Porter, Jeff; Laverón-Simavilla, Ana; Tinao Perez-Miravete, Ignacio; Fernandez Fraile, Jose Javier

    2016-07-01

    Vibrations induce a range of different interfacial phenomena in fluid systems depending on the frequency and orientation of the forcing. With gravity, (large) interfaces are approximately flat and there is a qualitative difference between vertical and horizontal forcing. Sufficient vertical forcing produces subharmonic standing waves (Faraday waves) that extend over the whole interface. Horizontal forcing can excite both localized and extended interfacial phenomena. The vibrating solid boundaries act as wavemakers to excite traveling waves (or sloshing modes at low frequencies) but they also drive evanescent bulk modes whose oscillatory pressure gradient can parametrically excite subharmonic surface waves like cross-waves. Depending on the magnitude of the damping and the aspect ratio of the container, these locally generated surfaces waves may interact in the interior resulting in temporal modulation and other complex dynamics. In the case where the interface separates two fluids of different density in, for example, a rectangular container, the mass transfer due to vertical motion near the endwalls requires a counterflow in the interior region that can lead to a Kelvin-Helmholtz type instability and a ``frozen wave" pattern. In microgravity, the dominance of surface forces favors non-flat equilibrium configurations and the distinction between vertical and horizontal applied forcing can be lost. Hysteresis and multiplicity of solutions are more common, especially in non-wetting systems where disconnected (partial) volumes of fluid can be established. Furthermore, the vibrational field contributes a dynamic pressure term that competes with surface tension to select the (time averaged) shape of the surface. These new (quasi-static) surface configurations, known as vibroequilibria, can differ substantially from the hydrostatic state. There is a tendency for the interface to orient perpendicular to the vibrational axis and, in some cases, a bulge or cavity is induced

  17. Microbial Metabolism in Serpentinite Fluids

    NASA Astrophysics Data System (ADS)

    Crespo-Medina, M.; Brazelton, W. J.; Twing, K. I.; Kubo, M.; Hoehler, T. M.; Schrenk, M. O.

    2013-12-01

    Serpentinization is the process in which ultramafic rocks, characteristic of the upper mantle, react with water liberating mantle carbon and reducing power to potenially support chemosynthetic microbial communities. These communities may be important mediators of carbon and energy exchange between the deep Earth and the surface biosphere. Our work focuses on the Coast Range Ophiolite Microbial Observatory (CROMO) in Northern California where subsurface fluids are accessible through a series of wells. Preliminary analyses indicate that the highly basic fluids (pH 9-12) have low microbial diversity, but there is limited knowledge about the metabolic capabilities of these communties. Metagenomic data from similar serpentine environments [1] have identified Betaproteobacteria belonging to the order Burkholderiales and Gram-positive bacteria from the order Clostridiales as key components of the serpentine microbiome. In an effort to better characterize the microbial community, metabolism, and geochemistry at CROMO, fluids from two representative wells (N08B and CSWold) were sampled during recent field campaigns. Geochemical characterization of the fluids includes measurements of dissolved gases (H2, CO, CH4), dissolved inorganic and organic carbon, volatile fatty acids, and nutrients. The wells selected can be differentiated in that N08B had higher pH (10-11), lower dissolved oxygen, and cell counts ranging from 105-106 cells mL-1 of fluid, with an abundance of the betaproteobacterium Hydrogenophaga. In contrast, fluids from CSWold have slightly lower pH (9-9.5), DO, and conductivity, as well as higher TDN and TDP. CSWold fluid is also characterized for having lower cell counts (~103 cells mL-1) and an abundance of Dethiobacter, a taxon within the phylum Clostridiales. Microcosm experiments were conducted with the purpose of monitoring carbon fixation, methanotrophy and metabolism of small organic compounds, such as acetate and formate, while tracing changes in fluid

  18. Fluid turbulence - Deterministic or statistical

    NASA Astrophysics Data System (ADS)

    Cheng, Sin-I.

    The deterministic view of turbulence suggests that the classical theory of fluid turbulence may be treating the wrong entity. The paper explores the physical implications of such an abstract mathematical result, and provides a constructive computational demonstration of the deterministic and the wave nature of fluid turbulence. The associated pressure disturbance for restoring solenoidal velocity is the primary agent, and its reflection from solid surface(s) the dominant mechanism of turbulence production. Statistical properties and their modeling must address to the statistics of the uncertainties of initial boundary data of the ensemble.

  19. [And Sarah Félix created "L 'Eau des Fées" and "La Parfumerie des Fées"].

    PubMed

    Raynal, Cécile

    2015-12-01

    century, the parisian perfumery of Sarah Felix was famous especially for her cosmetic "L'Eau des Fées" ("Water of the Fairies"), a dyeing supposed to give back to the old hair the color of their youth. Sarah Felix, sister of the famous actress Rachel, exercised several jobs before becoming perfumer. At first, she was actress, then she tried ... oyster culture in Normandy ! Abandoning these activities, Sarah Felix became really a businesswoman in Paris. She dedicated herself to perfumery, in particular to "L'Eau des Fées", from 1866. To launch its product, she was associated to competency characters (engineer, pharmacist, physician) and benefited from the protection of the imperial family. A lawsuit between the associates and the 1870 war hindered the company's early days, but "L'Eau des Fées" provided with quality pledges, imposed itself definitely. The "Parfumerie des Fées" completed the range of its cosmetics with creams, powders, etc. Sarah Félix paid attention to present "L'Eau des Fées" as a dye devoid of toxicity. Was it really the case and could il be sold nowadays? These two issues are discussed in the last part.

  20. Occupational exposure to metalworking fluid mist and sump fluid contaminants.

    PubMed

    Simpson, A T; Stear, M; Groves, J A; Piney, M; Bradley, S D; Stagg, S; Crook, B

    2003-01-01

    This paper summarizes the analytical and occupational hygiene findings from a recent survey of occupational exposure to metalworking fluids (MWFs) in the engineering industry. The aim of the survey was to link MWF mist exposure measurements with particular engineering processes and controls, and utilize the data obtained to develop exposure standards. At the same time the opportunity was taken to assess fluid management and control, including bacterial and fines contamination in the machine sumps. In general, occupational exposure to mineral oil MWF mist was controlled to <3 mg/m(3) (8 h time-weighted average) and to <1 mg/m(3) for water-mix MWF mist (in terms of the concentrate). These exposure values do not necessarily represent best practice, but are believed to be achievable and representative of industry as a whole. Gravimetric analysis of the total inhalable particulate was found to be a good predictor of mineral oil MWF mist but not for water-mix MWF mist. Grinding and drilling operations produced higher exposures than turning and milling for water-mix fluids. There were insufficient data to compare machining operations for mineral oil MWFs. On the whole, fluid management was found to be poor, with most sites failing to meet industry good practice or Health & Safety Executive (HSE) standards. Some of the operating procedures utilized were deficient or unsatisfactory. Poor standards of fluid management were found at all sizes of company. High levels of bacteria, endotoxin and fines were found in sumps, and control of other factors, such as water-mix fluid concentration, was often poor. Mineral oils had higher levels of fines than water-mix fluids (medians of 395 and 18 mg/l, respectively), and grinding produced high levels of fines in both types of MWF. Many water-mix sumps contained bacterial levels of >1 x 10(6) CFU/ml, and endotoxin levels of >100 000 EU/ml were not uncommon. The median values were 109 000 CFU/ml and 8039 EU/ml, respectively. Mists could

  1. Restauration adaptative des contours par une approche inspiree de la prediction des performances

    NASA Astrophysics Data System (ADS)

    Rousseau, Kami

    En teledetection, les cartes de contours peuvent servir, entre autres choses, a la restitution geometrique, a la recherche d'elements lineaires, ainsi qu'a la segmentation. La creation de ces cartes est faite relativement tot dans la chaine de traitements d'une image. Pour assurer la qualite des operations subsequentes, il faut veiller a obtenir une carte de contours precise. Notre problematique est de savoir s'il est possible de diminuer la perte de temps liee au choix d'algorithme et de parametre en corrigeant automatiquement la carte de contours. Nous concentrerons donc nos efforts sur le developpement d'une methode de detection/restauration de contours adaptative. Notre methode s'inspire d'une technique de prediction des performances d'algorithmes de bas niveau. Elle consiste a integrer un traitement par reseau de neurones a une methode " classique " de detection de contours. Plus precisement, nous proposons de combiner la carte de performances avec la carte de gradient pour permettre des decisions plus exactes. La presente etude a permis de developper un logiciel comprenant un reseau de neurones entraine pour predire la presence de contours. Ce reseau de neurones permet d'ameliorer les decisions de detecteurs de contours, en reduisant le nombre de pixels de fausses alarmes et de contours manques. La premiere etape de ce travail consiste en une methode d'evaluation de performance pour les cartes de contours. Une fois ce choix effectue, il devient possible de comparer les cartes entre elles. Il est donc plus aise de determiner, pour chaque image, la meilleure detection de contours. La revue de la litterature realisee simultanement a permis de faire un choix d'un groupe d'indicateurs prometteurs pour la restauration de contours. Ces derniers ont servi a la calibration et a l'entrainement d'un reseau de neurones pour modeliser les contours. Par la suite, l'information fournie par ce reseau a ete combinee par multiplication arithmetique avec les cartes d

  2. Cognitive Task Analysis (l’Analyse des taches cognitives)

    DTIC Science & Technology

    2000-10-01

    pilotage, guidage, gestion de produits chimiques), aujourd’hui, le CTA est principalement utilisé pour des tâches décisionnelles telles que le...adéquation entre les fonctions système et les capacités cognitives humaines (2) optimisation des performances système et de la charge de travail (3...S.E. DGA Etas Division Facteurs Humains Professor Emeritus Cognitive & Neural S&T Division BP 36 Route de Laval The University of Warwick Office of

  3. Cytology exam of pleural fluid

    MedlinePlus

    ... the lungs. This area is called the pleural space. Cytology means the study of cells. ... A sample of fluid from the pleural space is needed. The sample is taken using a procedure called thoracentesis . The procedure is done in the following way: You sit on a ...

  4. Flow sensor for biomedical fluids

    NASA Technical Reports Server (NTRS)

    Winkler, H. E.

    1981-01-01

    Electronic sensor accurately measures and controls flow of plasma, whole blood, or drugs in solution. Since sensor does not directly contact fluid, it does not have to be sterilized. It is compatible with disposable bottles, tubes, and hypodermic needles widely used in hospitals. Only modification necessary is in tube, which must contain two small metal inserts, spaced to fit in curved thermistor plates.

  5. Level Sensor for Cryogenic Fluids

    NASA Technical Reports Server (NTRS)

    Simmons, N. E.; Schroff, R. A.

    1983-01-01

    Hot wire sensor combined with voltage-comparator circuit monitors liquid level in cryogenic-fluid storage tanks. Sensor circuit adaptable to different liquids and sensors. Constant-current source drives current through sensing probe and fixed resistor. Voltage comparator circuits interpret voltage drops to tell whether probe is immersed in liquid and is current in probe.

  6. Fundamentals of Geophysical Fluid Dynamics

    NASA Astrophysics Data System (ADS)

    McWilliams, James C.

    2006-07-01

    Earth's atmosphere and oceans exhibit complex patterns of fluid motion over a vast range of space and time scales. These patterns combine to establish the climate in response to solar radiation that is inhomogeneously absorbed by the materials comprising air, water, and land. Spontaneous, energetic variability arises from instabilities in the planetary-scale circulations, appearing in many different forms such as waves, jets, vortices, boundary layers, and turbulence. Geophysical fluid dynamics (GFD) is the science of all these types of fluid motion. This textbook is a concise and accessible introduction to GFD for intermediate to advanced students of the physics, chemistry, and/or biology of Earth's fluid environment. The book was developed from the author's many years of teaching a first-year graduate course at the University of California, Los Angeles. Readers are expected to be familiar with physics and mathematics at the level of general dynamics (mechanics) and partial differential equations. Covers the essential GFD required for atmospheric science and oceanography courses Mathematically rigorous, concise coverage of basic theory and applications to both oceans and atmospheres Author is a world expert; this book is based on the course he has taught for many years Exercises are included, with solutions available to instructors from solutions@cambridge.org

  7. Cryogenic fluid management in space

    NASA Technical Reports Server (NTRS)

    Antar, Basil N.

    1988-01-01

    Many future space based vehicles and satellites will require on orbit refuelling procedures. Cryogenic fluid management technology is being developed to assess the requirements of such procedures as well as to aid in the design and development of these vehicles. Cryogenic fluid management technology for this application could be divided into two areas of study, one is concerned with fluid transfer process and the other with cryogenic liquid storage. This division is based upon the needed technology for the development of each area. In the first, the interaction of fluid dynamics with thermodynamics is essential, while in the second only thermodynamic analyses are sufficient to define the problem. The following specific process related to the liquid transfer area are discussed: tank chilldown and fill; tank pressurization; liquid positioning; and slosh dynamics and control. These specific issues are discussed in relation with the required technology for their development in the low gravity application area. In each process the relevant physics controlling the technology is identified and methods for resolving some of the basic questions are discussed.

  8. Brake Fluid Compatibility with Hardware

    DTIC Science & Technology

    2014-05-19

    had two servo valves for each wheel. One of the wheel servo valves controlled pressurized fluid to the brake calipers , while the second servo valve...was responsible for anti-lock or brake release action by relieving caliper circuit pressure back to the reservoir. Brake circuit action was initiated...

  9. Fluid-powered subsurface pump

    SciTech Connect

    Gipson, T.C.

    1991-12-03

    This paper describes a fluid-powered pump for attachment to small diametered coiled tubing for pumping subsurface liquid from a well production tube. It comprises: a pump housing having an upper end and a lower end, the upper end releasably attachable to a downhole end of the coiled tubing, the inside of the upper end of the housing in fluid communication with the inside of the coiled tubing; a cross head seal member dividing the pump into an upper chamber and a lower chamber, the upper chamber in fluid communication with the inside of the coiled tubing; a pump actuator extending between the upper and lower chambers, the actuator having an upper piston head sealingly fitted to reciprocate in the upper chamber and a lower piston head sealingly fitted to reciprocate in the lower chamber, the upper piston head and the lower piston head connected to each other by a connector rod sealing slidable in the cross head seal member, the actuator having a conduit for fluid communication between the upper chamber and the lower chamber, the conduit extending from an orifice in the top surface of the upper piston head, through the connector rod to a port above the top surface of the lower piston head.

  10. Cosmological mesonic viscous fluid model

    NASA Astrophysics Data System (ADS)

    Mohanty, G.; Pradhan, B. D.

    1992-01-01

    A class of exact nonstatic solutions is obtained for Einstein field equations in a closed elliptic Robertson-Walker spacetime filled with viscous perfect fluid in the presence of attractive scalar fields. The solutions characterize strong interaction of elementary particles. It is also shown that the massive graviton possesses zero spin.

  11. Microfilaria in hydrocele fluid cytology.

    PubMed

    Chandran, Patricia Ann; Jayaram, Gita; Mahmud, Rohela; Anuar, A Khairul

    2004-12-01

    Filariasis, a parasitic infection endemic in parts of India, Myanmar, islands of the South Pacific, West and East Africa and Saudi Arabia can be diagnosed from various types of cytopathological specimens. This case documents the detection of filarial infection from hydrocele fluid cytology in a 30-year-old Myanmar migrant worker in Malaysia.

  12. Fluid Power, Rate Training Manual.

    ERIC Educational Resources Information Center

    Bureau of Naval Personnel, Washington, DC.

    Fundamentals of hydraulics and pneumatics are presented in this manual, prepared for regular navy and naval reserve personnel who are seeking advancement to Petty Officer Third Class. The history of applications of compressed fluids is described in connection with physical principles. Selection of types of liquids and gases is discussed with a…

  13. Directed flow fluid rinse trough

    DOEpatents

    Kempka, Steven N.; Walters, Robert N.

    1996-01-01

    Novel rinse troughs accomplish thorough uniform rinsing. The tanks are suitable for one or more essentially planar items having substantially the same shape. The troughs ensure that each surface is rinsed uniformly. The new troughs also require less rinse fluid to accomplish a thorough rinse than prior art troughs.

  14. Directed flow fluid rinse trough

    DOEpatents

    Kempka, S.N.; Walters, R.N.

    1996-07-02

    Novel rinse troughs accomplish thorough uniform rinsing. The tanks are suitable for one or more essentially planar items having substantially the same shape. The troughs ensure that each surface is rinsed uniformly. The new troughs also require less rinse fluid to accomplish a thorough rinse than prior art troughs. 9 figs.

  15. General Transient Fluid Flow Algorithm

    SciTech Connect

    Amsden, A. A.; Ruppel, H. M.; Hirt, C. W.

    1992-03-12

    SALE2D calculates two-dimensional fluid flows at all speeds, from the incompressible limit to highly supersonic. An implicit treatment of the pressure calculation similar to that in the Implicit Continuous-fluid Eulerian (ICE) technique provides this flow speed flexibility. In addition, the computing mesh may move with the fluid in a typical Lagrangian fashion, be held fixed in an Eulerian manner, or move in some arbitrarily specified way to provide a continuous rezoning capability. This latitude results from use of an Arbitrary Lagrangian-Eulerian (ALE) treatment of the mesh. The partial differential equations solved are the Navier-Stokes equations and the mass and internal energy equations. The fluid pressure is determined from an equation of state and supplemented with an artificial viscous pressure for the computation of shock waves. The computing mesh consists of a two-dimensional network of quadrilateral cells for either cylindrical or Cartesian coordinates, and a variety of user-selectable boundary conditions are provided in the program.

  16. Fluid Mechanics in Sommerfeld's School

    NASA Astrophysics Data System (ADS)

    Eckert, Michael

    2015-01-01

    Sommerfeld's affiliation with fluid mechanics started when he began his career as an assistant of the mathematician Felix Klein at Göttingen. He always regarded fluid mechanics as a particular challenge. In 1904, he published a theory of hydrodynamic lubrication. Four years later, he conceived an approach for the analysis of flow instability (the Orr-Sommerfeld approach) as an attempt to account for the transition from laminar to turbulent flow. The onset of turbulence also became a major challenge for some of his pupils, in particular Ludwig Hopf and Fritz Noether. Both contributed considerably to elaborate the Orr-Sommerfeld theory. Heisenberg's doctoral work was another attempt in this quest. When Sommerfeld published his lectures on theoretical physics during World War II, he dedicated one of the six volumes to the mechanics of continuous media. With chapters on boundary layer theory and turbulence, it exceeded the scope of contemporary theoretical physics—revealing Sommerfeld's persistent appreciation of fluid mechanics. He resorted to Prandtl's Göttingen school of fluid mechanics in order to stay abreast of the rapid development of these specialties.

  17. Fluid Dynamics Lagrangian Simulation Model

    DTIC Science & Technology

    1994-02-08

    Virginia 22102 (703) 821-43"K Oth~er SAIC Offices Albuquerque. Boston. Colorado Springs . Dayton, Huntsville. Las Vegas, Los AngeLes. Oak Ridge, Orlando...of a Cylinder Wake Subjected to Localized Surface Ex- Journal of Fluid Mechanics, Vol. 191. pp. 197-223. citation."Jogrialof -jdd Mecanics , Vol. 234

  18. Fluid mechanics of heart valves.

    PubMed

    Yoganathan, Ajit P; He, Zhaoming; Casey Jones, S

    2004-01-01

    Valvular heart disease is a life-threatening disease that afflicts millions of people worldwide and leads to approximately 250,000 valve repairs and/or replacements each year. Malfunction of a native valve impairs its efficient fluid mechanic/hemodynamic performance. Artificial heart valves have been used since 1960 to replace diseased native valves and have saved millions of lives. Unfortunately, despite four decades of use, these devices are less than ideal and lead to many complications. Many of these complications/problems are directly related to the fluid mechanics associated with the various mechanical and bioprosthetic valve designs. This review focuses on the state-of-the-art experimental and computational fluid mechanics of native and prosthetic heart valves in current clinical use. The fluid dynamic performance characteristics of caged-ball, tilting-disc, bileaflet mechanical valves and porcine and pericardial stented and nonstented bioprostheic valves are reviewed. Other issues related to heart valve performance, such as biomaterials, solid mechanics, tissue mechanics, and durability, are not addressed in this review.

  19. Comparison des donnees simulees des capteurs de SPOT et landsat-D: Application a une region agricole

    NASA Astrophysics Data System (ADS)

    Saint, Gilbert; Podaire, Alain

    La modélisation de la luminance spectrale des objets observés en télédétection permet d'effectuer des simulations de différents capteurs à partir de données obtenues au moyen d'un scanneur DAEDALUS aéroporté : les qualités radiométrique et géométrique ont pu être évaluées par une comparaison avec des données Landsat réelles. L'analyse sur une zone agricole met surtout en évidence le rôle important de l'accroissement de la résolution.

  20. Analyse des facteurs prédictifs de malignité des goitres nodulaires : à propos de 500 cas

    PubMed Central

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

    2016-01-01

    Les nodules thyroïdiens sont très fréquents et moins de 10% d'entre eux sont malin. Ils posent un véritable problème diagnostique et thérapeutique surtout par rapport à leur nature bénigne ou maligne. L’étude de certains facteurs cliniques et paracliniques de présomption de malignité permet de bien codifier la stratégie thérapeutique. Le but de ce travail est d’étudier les facteurs prédictifs de malignité des goitres nodulaires et comparer nos résultats à ceux de la littérature. Il s'agit d'une étude rétrospective à propos de 500 cas de goitres nodulaires opérés au service d'Oto-rhino-laryngologie (ORL) et Chirurgie cervico-faciale (CCF) de l'hôpital militaire Avicenne de Marrakech entre 2006 et 2012. Le pourcentage de cancers a été de 6,8%. L’âge moyen de nos patients était de 46 ans, avec une sex-ratio de 5 (F/H). A la palpation cervicale; le caractère dure du nodule a été constaté dans 94,4% des cas de cancer, avec des limites irrégulières dans 64,70% des cas de cancer. Trois nodules étaient fixes et ils étaient tous malins. Les adénopathies cervicales ont été constatées chez 8 malades dont 7 présentaient des cancers. A l’échographie, 61,8% des nodules malins présentaient un aspect hypoéchogène, avec des contours flous dans 88,24% des cas. La vascularisation intra nodulaire était présente dans 35,3% de ces cas des cancers avec des microcalcifications chez 55,9% d'entre eux. Le halo hypoéchogene périnodulaire était incomplet dans 73,5% des cas de cancer. Nos patients étaient en euthyroïdie dans 84,6% des cas. Les facteurs prédictifs de malignité d'un goitre nodulaire, étaient donc dans notre étude d'abord cliniques: l’âge supérieur à 60 ans, la consistance dure du nodule, sa fixité, son caractère irrégulier et mal limité à la palpation, ainsi que la présence d'adénopathie(s) cervicale(s) à l'examen; et échographiques: le caractère hypoéchogène, les limites floues, la présence de

  1. Fluid diffusion in porous silica

    NASA Astrophysics Data System (ADS)

    McCann, Lowell I.

    Fluid motion in porous media has received a great deal of theoretical and experimental attention due to its importance in systems as diverse as ground water aquifers, catalytic processes, and size separation schemes. Often, the motion of interest is the random thermal motion of molecules in a fluid undergoing no net flow. This diffusive motion is particularly important when the size of the pores is nearly the same as the size of the molecules. In this study, fluid diffusion is measured in several varieties of porous silica whose pore structure is determined by the process by which it is made. The samples in this study have porosities (φ, the ratio of the pore volume to the total sample volume) that vary from 0.3 to 0.75 and average pore radii that range from approximately 15 to 120 A. Determining the effect of the pore structure on the diffusion of a liquid in a porous material is complicated by the chemical interactions between the diffusing molecules and the pore surface. In this study, ions in a hydrophilic fluid are used to block the adsorption of the diffusing dye molecules to the hydroxyl groups covering the silica surface. This technique is unlike typical surface treatments of silica in that it does not permanently alter the pore geometry. In this work, fluid diffusion is measured with a transient holographic grating technique where interfering laser beams create a periodic refractive index modulation in the fluid. The diffraction of a third laser off this grating is monitored to determine how quickly the grating relaxes, thereby determining the diffusion coefficient of the molecules in the fluid. Varying the grating periodicity controls the length scale of the diffusion measurement from 1.2 to 100 μm which is much larger than the average pore sizes of the samples. Therefore, over these large scales, we measure 'normal' diffusion, where the mean squared displacement of a diffusing particle varies linearly with time. In one particular type of porous silica

  2. Progress in geophysical fluid dynamics

    NASA Astrophysics Data System (ADS)

    Robinson, Allan R.

    Geophysical fluid dynamics deals with the motions and physics of the atmosphere, oceans and interior of the earth and other planets: the winds, the swirls, the currents that occur on myriads of scales from millimeter to climatological. Explanations of natural phenomena, basic processes and abstractions are sought. The rotation of the earth, the buoyancy of its fluids and the tendency towards large-scale turbulence characterize these flows. But geophysical fluid dynamics is importantly a part of modern fluid dynamics which is contributing to the development of nonlinear mechanics generally. Some general insights are emerging for nonlinear systems which must be regarded as partly deterministic and partly random or which are complex and aperiodic. Contributions from geophysical fluid dynamics come from its methodology, from the experience of examples, and from the perspective provided by its unique scale. Contributions have been made to turbulent, chaotic and coherently structured nonlinear process research. Turbulent vortices larger than man himself naturally invite detailed investigation and deterministic physical studies. Examples are storms in the atmosphere and large ring vortices spun off by the Gulf Stream current in mid-ocean. The statistics of these events determine critical aspects of the general circulations. Fluid dynamicists generally now know that it is often relevant or necessary to study local dynamical processes of typical eddies even though only the average properties of the flow are of interest; progress in understanding the turbulent boundary layer in pipes involves the study of millimeter-scale vortices. Weather-related studies were seminal to the construction of the new scientific field of chaos. Coherent vortices abound of which the Great Red Spot of Jupiter is a spectacular example. Geophysical fluid dynamicists have been among forefront researchers in exploiting the steadily increasing speed and capacity of modern computers. Supercomputers

  3. Curious Fluid Flows: From Complex Fluid Breakup to Helium Wetting

    NASA Astrophysics Data System (ADS)

    Huisman, Fawn Mitsu

    This work encompasses three projects; pinch-off dynamics in non-Newtonian fluids; helium wetting on alkali metals; and the investigation of quartz tuning forks as cryogenic pressure transducers. Chapter 1 discusses the breakup of a non-Newtonian yield stress fluid bridge. We measured the minimum neck radius, hmin, as a function of time and fit it to a power law with exponent n 1. We then compare n1 to exponent n2, obtained from a rotational rheometer using a Herschel-Bulkley model. We confirm n1=n2 for the widest variety of non-Newtonian fluids to date. When these fluids are diluted with a Newtonian fluid n1 does not equal n2. No current models predict that behavior, identifying a new class of fluid breakup. Chapter 2 presents the first chemical potential-temperature phase diagram of helium on lithium, sodium and gold, using a novel pressure measurement system. The growth and superfluid transition of a helium film on these substrates is measured via an oscillator for isotherms (fixed temperature, varying amount of helium gas), and quenches (fixed amount of helium gas, varying temperature). The chemical potential-temperature plot is similar for gold, lithium and sodium despite the large difference in the substrate binding energies. No signs of a 2-D liquid-vapor transition were seen. Chapter 3 discusses the creation of a 32.768 kHz quartz tuning fork in situ pressure transducer. Tuning forks are used to measure pressure at room temperature, but no work addresses their potential as cryogenic pressure transducers. We mapped out the behavior of a tuning fork as a function of pressure at 298, 7.0, 2.5, 1.6, 1.0 and 0.7 K by measuring the quality factor. The fork is sensitive to pressures above 0.1 mTorr, limiting its use as a pressure gauge at 0.6 K and below. The experimental curves were compared to a theoretical Q(P, T) function that was refined using the 298 K data. At cryogenic temperatures the formula breaks down in the viscous region and becomes inaccurate. The

  4. Apport des neutrons à l'analyse structurale des composés partiellement désordonnés

    NASA Astrophysics Data System (ADS)

    Cousson, A.

    2003-02-01

    La cristallographie est un outil extrêmement puissant qui pourrait être utilisé par de nombreux scientifiques dont les sujets de recherche sont en fait très éloignés. L'évolution des techniques ces dernières années a relégué par exemple la cristallographie des rayons X des petites molécules à un rôle mineur, un rôle de service. Certains ont même le sentiment semble-t-il que toutes les connaissances sont contenues dans de multiples logiciels capables par eux-mêmes de conduire une analyse structurale à un résultat correct unique. Il est souhaitable que chacun soit capable de réaliser l'étude structurale du composé qui l'intéresse et bien entendu nécessaire de comprendre ce que l'on fait, la qualité des résultats et leur analyse en dépend. L'objet de cette présentation est de montrer l'apport spécifique de la diffraction de neutrons sur monocristaux à l'étude du désordre, en particulier des atomes d'hydrogène, et ses conséquences sur la compréhension des propriétés physiques, à partir de développements et d'exemples récents.

  5. Classification of DES16C2nm as a SLSN at z=1.998

    NASA Astrophysics Data System (ADS)

    Galbany, L.; D'Andrea, C.; Prajs, S.; Smith, M.; Sullivan, M.; Ponder, K.; Gonzalez-Gaitan, S.; Forster, F.; Hamuy, M.; Prieto, Jose Luis; Schubnell, M.; Kessler, R.; Lasker, J.; Scolnic, D.; Brout, D. J.; Gladney, L.; March, M.; Sako, M.; Wolf, R. C.; Brown, P. J.; Krisciunas, K.; Suntzeff, N.; Macaulay, E.; Nichol, R.; Childress, M.; Maartens, R.; Kovacs, E.; Kuhlmann, S.; Spinka, H.; Ahn, E.; Finley, D. A.; Frieman, J.; Marriner, J.; Wester, W.; Aldering, G.; Gupta, R.; Kim, A. G.; Thomas, R. C.; Barbary, K.; Bloom, J. S.; Goldstein, D.; Nugent, P.; Perlmutter, S.; Foley, R. J.; Pan, Y.-C.; Casas, R.; Castander, F. J.; Papadopoulos, A.; Morganson, E.; Desai, S.; Paech, K.; Smith, R. C.

    2016-11-01

    We report the spectroscopic classification of DES16C2nm as a superluminous supernova (SLSN) discovered by the Dark Energy Survey (ATEL #4668). DES16C2nm was discovered in the first epoch of DES Y4, on 22 August 2016 at R.A. = 03:40:14.83, Decl = -29:05:53.5 with i = 23.2 mag. DES16C2nm has a non-detection in the final epoch of DES Y3 on 08 February 2016.

  6. Calendar of Selected Aeronautical and Space Meetings July 1988 (Calendrier des Manifestations Aeronautiques et Spatiales (Selecgion) Juillet 1988)

    DTIC Science & Technology

    1988-07-01

    Electronique, Optique et M~trologie 6 03 - M46anique dui Vol 33 04 - Dynamnique des Fluides; et Acoustique 35 05 - Navigation, Guidage et Pilotage 42 06...Ferromagnetism 07-06, 07-10, 07-12, 07-58, 07-73, 07-74, 07-76, 07-78, 07-79 Fibre Optics 02-08, 02-10, 02-22, 02-23, 02-32, 02-33, 02-35, 02-65, 02-73, 02...74, 02-88, 02-93, 02-94, 02-107, 02-113 Fibre Reinforced Plastics 07-19, 07-27, 12-10 Films 07-21 Filters 04-21 Finite Element Methods 09-17 Fire

  7. Formation des etoiles massives dans les galaxies spirales

    NASA Astrophysics Data System (ADS)

    Lelievre, Mario

    Le but de cette thèse est de décrire la formation des étoiles massives dans les galaxies spirales appartenant à divers types morphologiques. L'imagerie Hα profonde combinée à une robuste méthode d'identification des régions HII ont permis de détecter et de mesurer les propriétés (position, taille, luminosité, taux de formation d'étoiles) de plusieurs régions HII situées dans le disque interne (R < R25) de dix galaxies mais aussi à leur périphérie (R ≥ R 25). De façon générale, la répartition des régions HII ne montre aucune évidence de structure morphologique à R < R25 (bras spiraux, anneau, barre) à moins de limiter l'analyse aux régions HII les plus grosses ou les plus lumineuses. La répartition des régions HII, de même que leur taille et leur luminosité, sont toutefois sujettes à de forts effets de sélection qui dépendent de la distance des galaxies et qu'il faut corriger en ramenant l'échantillon à une résolution spatiale commune. Les fonctions de luminosité montrent que les régions HII les plus brillantes ont tendance à se former dans la portion interne du disque. De plus, l'analyse des pentes révèle une forte corrélation linéaire par rapport au type morphologique. Aucun pic n'est observé dans les fonctions de luminosité à log L-37 qui révèlerait la transition entre les régions HII bornées par l'ionisation et par la densité. Une relation cubique est obtenue entre la taille et la luminosité des régions HII, cette relation variant toutefois de façon significative entre le disque interne et la périphérie d'une même galaxie. La densité et la dynamique du gaz et des étoiles pourraient influencer de façon significative la stabilité des nuages moléculaires face à l'effondrement gravitationnel. D'une part, l'étendue du disque de régions HII pour cinq galaxies de l'échantillon coïncide avec celle de l'hydrogène atomique. D'autre part, en analysant la stabilité des disques galactiques, on conclue

  8. Symetries et integrabilite des equations aux differences finies

    NASA Astrophysics Data System (ADS)

    Lafortune, Stephane

    2000-09-01

    La présente thèse porte sur l'étude des symétries et des propriétés d'intégrabilité des équations aux différences finies. Dans le chapitre 1, le groupe de symétrie ponctuelle d'un système couplé à deux équations différentielles aux différences est étudié. On montre que dans certains cas, la dimension du groupe peut être infinie. Les équations peuvent décrire l'interaction de deux longues chaînes moléculaires, chacune étant composée d'atomes d'un même type. Dans le chapitre 2, une classe de théories de champs avec interaction exponentielle est introduite. L'interaction dépend de deux matrices de ``couplage'' et est suffisamment générale pour inclure toutes les théories de champs de Toda existant dans la littérature. Les symétries de Lie ponctuelles sont obtenues pour les cas où l'on a un nombre fini, infini ou semi-infini de champs. Une attention spéciale est accordée à la présence de l'invariance conforme. Dans le chapitre 3, nous procédons à la classification et à l'étude d'équations linéarisables. Nous examinons tout d'abord l'équation de Gambier continue qui contient, comme réductions, toutes les équations de deuxième ordre intégrables par linéarisation. Nous introduisons par la suite la forme discrète de cette équation et obtenons les conditions d'intégrabilité à l'aide du confinement des singularités. Nous étudions aussi les différentes réductions du cas discret. De plus, nous obtenons des transformations de Schlesinger pour les équations de Gambier discrète et continue. Dans la dernière partie du chapitre, nous étudions une famille d'équations discrètes du deuxième ordre incluant des équations résolubles par linéarisation. Plusieurs cas intégrables sont obtenus. Dans le cas discret, l'étude de l'intégrabilité est faite à l'aide du confinement des singularités. Dans le chapitre 4, nous étudions un autre critère d'intégrabilité: l'entropie algébrique. Nous montrons que les r

  9. Transport de paires EPR dans des structures mesoscopiques

    NASA Astrophysics Data System (ADS)

    Dupont, Emilie

    Dans cette these, nous nous sommes particulierement interesses a la propagation de paires EPR1 delocalisees et localisees, et a l'influence d'un supraconducteur sur le transport de ces paires. Apres une introduction de cette etude, ainsi que du cadre scientifique qu'est l'informatique quantique dans lequel elle s'inscrit, nous allons dans le chapitre 1 faire un rappel sur le systeme constitue de deux points quantiques normaux entoures de deux fils supraconducteurs. Cela nous permettra d'introduire une methode de calcul qui sera reutilisee par la suite, et de trouver egalement le courant Josephson produit par ce systeme transforme en SQUID-dc par l'ajout d'une jonction auxiliaire. Le SQUID permet de mesurer l'etat de spin (singulet ou triplet), et peut etre forme a partir d'autres systemes que nous etudierons ensuite. Dans le chapitre 2, nous rappellerons l'etude detaillee d'un intricateur d'Andreev faite par un groupe de Bale. La matrice T, permettant d'obtenir le courant dans les cas ou les electrons sont separes spatialement ou non, sera etudiee en detail afin d'en faire usage au chapitre suivant. Le chapitre 3 est consacre a l'etude de l'influence du bruit sur le fonctionnement de l'intricateur d'Andreev. Ce bruit modifie la forme du courant jusqu'a aboutir a d'autres conditions de fonctionnement de l'intricateur. En effet, le bruit present sur les points quantiques peut perturber le transport des paires EPR par l'intermediaire des degres de liberte. Nous montrerons que, du fait de l'"intrication" entre la charge de la paire et le bruit, la paire est detruite pour des temps longs. Cependant, le resultat le plus important sera que le bruit perturbe plus le transport des paires delocalisees, qui implique une resonance de Breit-Wigner a deux particules. Le transport parasite n'implique pour sa part qu'une resonance de Breit-Wigner a une particule. Dans le chapitre 4, nous reviendrons au systeme constitue de deux points quantiques entoures de deux fils

  10. Heat Transfer in Complex Fluids

    SciTech Connect

    Mehrdad Massoudi

    2012-01-01

    Amongst the most important constitutive relations in Mechanics, when characterizing the behavior of complex materials, one can identify the stress tensor T, the heat flux vector q (related to heat conduction) and the radiant heating (related to the radiation term in the energy equation). Of course, the expression 'complex materials' is not new. In fact, at least since the publication of the paper by Rivlin & Ericksen (1955), who discussed fluids of complexity (Truesdell & Noll, 1992), to the recently published books (Deshpande et al., 2010), the term complex fluids refers in general to fluid-like materials whose response, namely the stress tensor, is 'non-linear' in some fashion. This non-linearity can manifest itself in variety of forms such as memory effects, yield stress, creep or relaxation, normal-stress differences, etc. The emphasis in this chapter, while focusing on the constitutive modeling of complex fluids, is on granular materials (such as coal) and non-linear fluids (such as coal-slurries). One of the main areas of interest in energy related processes, such as power plants, atomization, alternative fuels, etc., is the use of slurries, specifically coal-water or coal-oil slurries, as the primary fuel. Some studies indicate that the viscosity of coal-water mixtures depends not only on the volume fraction of solids, and the mean size and the size distribution of the coal, but also on the shear rate, since the slurry behaves as shear-rate dependent fluid. There are also studies which indicate that preheating the fuel results in better performance, and as a result of such heating, the viscosity changes. Constitutive modeling of these non-linear fluids, commonly referred to as non-Newtonian fluids, has received much attention. Most of the naturally occurring and synthetic fluids are non-linear fluids, for example, polymer melts, suspensions, blood, coal-water slurries, drilling fluids, mud, etc. It should be noted that sometimes these fluids show Newtonian

  11. Compressor bleed cooling fluid feed system

    DOEpatents

    Donahoo, Eric E; Ross, Christopher W

    2014-11-25

    A compressor bleed cooling fluid feed system for a turbine engine for directing cooling fluids from a compressor to a turbine airfoil cooling system to supply cooling fluids to one or more airfoils of a rotor assembly is disclosed. The compressor bleed cooling fluid feed system may enable cooling fluids to be exhausted from a compressor exhaust plenum through a downstream compressor bleed collection chamber and into the turbine airfoil cooling system. As such, the suction created in the compressor exhaust plenum mitigates boundary layer growth along the inner surface while providing flow of cooling fluids to the turbine airfoils.

  12. Safety drain system for fluid reservoir

    NASA Technical Reports Server (NTRS)

    England, John Dwight (Inventor); Kelley, Anthony R. (Inventor); Cronise, Raymond J. (Inventor)

    2012-01-01

    A safety drain system includes a plurality of drain sections, each of which defines distinct fluid flow paths. At least a portion of the fluid flow paths commence at a side of the drain section that is in fluid communication with a reservoir's fluid. Each fluid flow path at the side communicating with the reservoir's fluid defines an opening having a smallest dimension not to exceed approximately one centimeter. The drain sections are distributed over at least one surface of the reservoir. A manifold is coupled to the drain sections.

  13. Opération multimode transverse des OPOs: des structures classiques aux corrélations quantiques

    NASA Astrophysics Data System (ADS)

    Martinelli, M.; Ducci, S.; Gigan, S.; Treps, N.; Maître, A.; Fabre, C.

    2002-06-01

    Nous démontrons la formation de structures transverses sur les faisceaux émis par un oscillateur paramétrique optique (OPO) de type II en configuration confocale. D'un point de vue classique nous mettons en évidence le caractère multimode transverse de telles structures. A travers l'étude des corrélations spatiales des faisceaux générés nous montrons que ces structures sont également multimodes d'un point de vue quantique.

  14. Apport des moyens endoscopiques dans la dilatation des sténoses caustiques de l’œsophage

    PubMed Central

    Seydou, Togo; Abdoulaye, Ouattara Moussa; xing, Li; Zi, Sanogo Zimogo; sekou, Koumaré; Wen, Yang Shang; Ibrahim, Sankare; Sekou, Toure Cheik Ahmed; Boubacar, Maiga Ibrahim; Saye, Jacque; Jerome, Dakouo Dodino; Dantoumé, Toure Ousmane; Sadio, Yena

    2016-01-01

    Introduction Toutes les sténoses symptomatiques de l’œsophage peuvent être dilatées par voie endoscopique. Nous évaluons l'apport des moyens endoscopiques dans la prise en charge de la dilatation œsophagienne pour sténose caustique de l’œsophage (SCO) au Mali. Méthodes IL s'agissait d'une étude descriptive et prospective réalisée dans le service de chirurgie thoracique à l'hôpital du Mali. Au total 46 dossiers cliniques de patients on été enregistrés et subdivisés en 4 groupes en fonction de la topographie des lésions cicatricielles. Le nombre de cas d'assistance endoscopique réalisé a été déterminé afin de comprendre l'apport des moyens endoscopiques dans le succès de la dilatation des SCO. Pour les 2 différentes méthodes de dilatation utilisées, le résultat du traitement et le coût ont comparés. Résultats La FOGD a été utilisée dans 19 cas (41.30%) de dilatation avec la bougie de Savary Guillard et dans 47.82% des cas dans la dilatation de Lerut. La vidéo-laryngoscopie a été utilisé 58.69% des cas de dilatation à la bougie de Lerut. Le passage de guide métallique et / ou de fil-guide a été réalisée dans 39.13% avec la vidéo laryngoscopie et dans 58.68% avec la FOGD. Dans la comparaison des deux méthodes, il existe une différence significative dans la survenue des complications (p=0.04075), l'anesthésie générale (p=0.02287), l'accessibilité à la méthode (p=0.04805) et la mortalité (p=0.00402). Conclusion La SCO est une pathologie grave et sous évaluée au Mali. Les moyens endoscopiques contribuent considérablement au succès de la dilatation œsophagienne pour sténose caustique dans les différentes méthodes utilisées. PMID:27200129

  15. Experimental and analytical study on fluid whirl and fluid whip modes

    NASA Technical Reports Server (NTRS)

    Muszynska, Agnes

    1994-01-01

    Fluid whirl and fluid whip are rotor self-excited, lateral vibrations which occur due to rotor interactions with the surrounding fluid. There exist various modes of fluid whirl and fluid whip. These modes are close to rotor modes corresponding to free vibrations (based on the linear model). Small differences are due to nonlinearities in the system. This paper presents experimental and analytical results on the lowest modes of fluid whirls and fluid whip. Examples of rotors supported in fluid lubricated bearings show the variations of rotor deflection amplitudes and phases in the whirl and whip modes with changes of rotative speeds and/or changes in lumped mass locations along the shaft.

  16. Bose Fluids Above Tc: Incompressible Vortex Fluids and ``Supersolidity''

    NASA Astrophysics Data System (ADS)

    Anderson, P. W.

    2008-05-01

    This Letter emphasizes that nonlinear rotational or diamagnetic susceptibility is characteristic of Bose fluids above their superfluid TC’s. For sufficiently slow rotation or, for superconductors, weak B fields, this amounts to an incompressible response to vorticity. The cause is that there are terms missing in the conventionally accepted model Hamiltonian for quantized vortices in the Bose fluid. The resulting susceptibility can account for recent observations of Chan et al. [Nature (London)NATUAS0028-0836 427, 225 (2004); 10.1038/nature02220ScienceSCIEAS0036-8075 305, 1941 (2004)10.1126/science.1101501] on solid He and Ong et al. [Europhys. Lett.EULEEJ0295-5075 72, 451 (2005)10.1209/epl/i2005-10254-4] on cuprate superconductors.

  17. Computational fluid dynamics uses in fluid dynamics/aerodynamics education

    NASA Technical Reports Server (NTRS)

    Holst, Terry L.

    1994-01-01

    The field of computational fluid dynamics (CFD) has advanced to the point where it can now be used for the purpose of fluid dynamics physics education. Because of the tremendous wealth of information available from numerical simulation, certain fundamental concepts can be efficiently communicated using an interactive graphical interrogation of the appropriate numerical simulation data base. In other situations, a large amount of aerodynamic information can be communicated to the student by interactive use of simple CFD tools on a workstation or even in a personal computer environment. The emphasis in this presentation is to discuss ideas for how this process might be implemented. Specific examples, taken from previous publications, will be used to highlight the presentation.

  18. Étude par diffraction des rayons X des vernis rouges des sigillées du sud de la Gaule. Les ateliers de la Graufesenque

    NASA Astrophysics Data System (ADS)

    Vendier, L.; Sciau, Ph.; Dooryhee, E.

    2002-07-01

    La Graufesenque (Millau, Aveyron) 1^rst and 2^nd, centuries AC Sigillata red slips have been studied by x-ray diffraction at ESRF and on a conventional diffractometer. Although x-ray diffraction is a non-destructive characterisation technique adapted to surface study, it has not been used so mutch for Sigillata slip characterisation. The poor quality of the slip surface can be an explanation. In this work we demonstrate that it is possible to get good quality diffraction diagrams on 20-120 AC Sigillata slips. The results confirm the productions homogeneity and the hypothesis about a non-local clay used for the slips. On a counterpart, the late (second half of 2^nd century AC) Sigillata study needs because of their crackled surface a high quality beam, which can only be accessible on a synchrotron installation. These productions seems to be more heterogeneous: some Sigillata present similar diffraction diagrams for the slip and ceramic body (same clay?), some others present results similar to the precedent production period ones. Les vernis rouges de poteries sigillées (I^er et II^e siècles) de la Graufesenque (Millau, Aveyron) ont été étudiés par diffraction des rayons X à la fois à l'ESRF et sur une installation classique de laboratoire. Bien que la diffraction des rayons X soit une technique adaptée à l'étude des surfaces, cette technique a jusqu'à présent assez peu servi dans l'examen de ces objets. Ceci peut en partie s'expliquer par le mauvais état de surface de certains vernis. Dans ce travail, nous montrons que moyennant quelques précautions, il est possible d'obtenir sur une installation classique de bons diffractogranunes des vernis des sigillées datés entre 20 et 120 ap. J.C. Les résultats confirment l'homogénéité de ces productions et l'hypothèse selon laquelle ces vernis n'ont pas été fabriqués à partir des argiles locales du jurassique environnant le site. Par contre, l'étude des sigillées tardives de la deuxième moitié du

  19. Investigation experimentale de l'ecoulement et des performances thermiques du nanofluide eau-oxyde de cuivre dans un Micro-Canal Chauffe

    NASA Astrophysics Data System (ADS)

    Rimbault, Benjamin

    Cette these de maitrise presentee par articles visait a etudier le comportement hydraulique et thermique d'un ecoulement de nanofluides en micro-canal chauffe. Nous avons etudie premierement de l'eau distillee, ensuite des melanges de particules d'oxyde de cuivre (taille 29nm) avec de l'eau distillee en concentrations particulaires volumiques 4.5%, 1.03%, et 0.24% (CuO-H2O). L'ecoulement force des differents fluides a ete realise au moyen de pompes a engrenages au sein d'un circuit ferme, comprenant un micro-canal a section rectangulaire (e=1.116mm,1=25.229mm) chauffe sur deux faces paralleles via des cartouches electriques, deux echangeurs de chaleurs en serie, ainsi qu'un debitmetre magnetique. A notre connaissance peu d'etudes sur l'ecoulement de nanofluides d'oxyde de cuivre-eau en micro-canal rectangulaire chauffe sont disponibles dans la litterature, cette recherche sert de contribution. Premierement, une validation avec la litterature a ete effectuee pour le cas d'un ecoulement d'eau entre plaques planes paralleles chauffees. Des essais hydrauliques ont ete realises pour une gamme du nombre de Reynolds allant jusqu'a Re=5000 a temperature constante. Par la suite des essais thermiques jusqu'a Re=2500 ont consiste en une elevation de temperature fixe (20.5°C a 30.5°C) a travers la longueur du micro-canal sous un regime stationnaire. Les resultats ont demontre une augmentation de la perte de pression et du coefficient de frottement des nanofluides sur l'eau pour un meme debit. Une telle augmentation de perte de pression etait de +70%, +25%, et +0 a 30% respectivement pour les concentrations 4.50%, 1.03%, et 0.24%. Concernant la transition laminaire a turbulent les comportements semblaient indiquer une valeur critique semblable entre l'eau et les differentes concentrations avec et sans chauffage a un nombre de Reynolds critique Rem 1000. Nous avons observe une legere augmentation du coefficient de convection thermique avec le debit massique pour les faibles

  20. Crossover critical phenomena in fluids

    NASA Astrophysics Data System (ADS)

    Kostrowicka Wyczalkowska, Anna Judyta

    In fluids the effects of critical density fluctuations remain significant over a large range of temperatures and densities. The nonanalytical behavior observed in real fluids in the vicinity of the critical point is well described by renormalization-group theory. This theory accounts properly for the influence of the critical fluctuations in density which are entirely neglected by the classical equations. Specifically, fluids asymptotically close to the critical point belong to the universality class of the 3-dimensional Ising model and their behavior near the critical point is governed by scaling laws with critical exponents appropriate for this universality class. The validity of the asymptotic power laws is, however, restricted to a very small region near the critical point. An approach to deal with the nonasymptotic behavior of fluids including the crossover from Ising behavior in the immediate vicinity of the critical point to classical behavior far away from the critical point has been developed by Chen and coworkers and is further improved in this thesis. This approach is based on earlier work of Nicoll and coworkers and it leads to a transformation of a classical Landau expansion to incorporate the effects of critical fluctuations. Here we show how this transformation applies to real fluids: water and sulfurhexafluoride. Nevertheless, even such a crossover Landau expansion still fails to make a connection with the behavior of the fluid very far away from the critical point like the ideal-gas limit at low densities. We demonstrate how a procedure, earlier developed to include the effects of critical fluctuations into a classical Landau expansion of the Helmholtz-energy density, can also be applied to a closed-form classical equation of state like the equation of van der Waals. One of the consequences of accounting for the presence of the critical fluctuations is a shift in the location of the critical point. The resulting equation incorporates the