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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. 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

  13. 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

  14. 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

  15. 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

  16. La détermination des distances: Sol, Hipparcos, GAIA.

    NASA Astrophysics Data System (ADS)

    Turon, C.

    Les parallaxes trigonométriques des étoiles les plus proches du soleil sont la base de la détermination des distances dans l'Univers. Elles permettent, par la calibration en luminosité des différents indicateurs de distance d'étalonner les distances d'abord dans notre Galaxie, puis dans les galaxies du Groupe Local, puis pour les galaxies plus lointaines. Cette base est, actuellement, très mince, et peu de types d'étoiles y sont représentés. Hipparcos va déjà apporter une amélioration sensible. Avec GAIA une révision complète des calibrations de luminosité de tous les indicateurs "primaires" serait directement possible.

  17. 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).

  18. 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

  19. Caractérisation géochimique des fluides associés aux minéralisations Pb sbnd Zn de Bou-Dahar (Maroc)

    NASA Astrophysics Data System (ADS)

    Adil, Samira; Bouabdellah, Mohammed; Grandia, Fidel; Cardellach, Esteve; Canals, Àngel

    2004-11-01

    The Bou-Dahar Pb sbnd Zn Mississippi Valley deposits located in the eastern part of the High Atlas Range (Morocco) are hosted by a Liassic reefal complex. Fluid inclusion and 'crush-leach' data show that two distinct fluids were involved in the mineralisation deposition: a warmer, more saline fluid (180 °C, >25 wt% NaCl equivalent) and a cooler, less saline fluid (70 °C, 16 wt% equivalent NaCl). Mixing of these two fluids resulted in the precipitation of the ore. The solute composition of the ore-forming brine suggests that the MVT mineralising fluids were probably a mixture of halite-dissolution fluids and evaporated seawater. To cite this article: S. Adil et al., C. R. Geoscience 336 (2004).

  20. Nature, origine et évolution des fluides dans le district minier de la caldeira d'oued bélif (nefza, Tunisie septentrionale)

    NASA Astrophysics Data System (ADS)

    Talbi, Fouad; Slim-Shimi, Najet; Tlig, Said; Zargouni, Fouad

    1999-02-01

    Fluid inclusion studies were undertaken on quartz, fluorite and calcites in the Oued Bélif caldera ore district in northern Tunisia. Two main groups of inclusions were distinguished: a fluid inclusion group, of magmatic origin, with a temperature higher than 350 °C and salinity higher than 30 wt % NaCl; and a group of mixing between magmatic and meteoric fluids with temperatures and salinities ranging from 150 to 250 °C and from 15 to 25 wt % NaCl, respectively. These two groups result from hydrothermal circulations of respectively, "porphyry copper" and epithermal systems; this is confirmed by the nature of the alteration.

  1. Mesure de la Polarisation des Lambda Produits dans les Collisions Positron-Electron AU Lep a L'aide du Detecteur Opal

    NASA Astrophysics Data System (ADS)

    Vandenplas, Denis

    Le Modele Standard est le cadre theorique general qui, jusqu'a present, a permis l'interpretation de tous les resultats experimentaux en physique des hautes energies. Cette theorie decrit, entre autres, la production d'une paire de particules elementaires, formee d'un quark et d'un antiquark, a partir de la desintegration de l'un des bosons mediateurs de l'interaction faible, le Z^0. Cependant, dans ce cas precis, la transformation subsequente des quarks primaires en particules reelles, un processus appele hadronisation, n'est decrite qu'a l'aide de modeles phenomenologiques. Afin de sonder les mecanismes de l'hadronisation, cette these presente la mesure du transfert du spin d'un quark etrange primaire a une particule appelee Lambda lors des desintegrations hadroniques du Z^0. L'etude a ete realisee dans le cadre de la collaboration OPAL, une des quatre experiences menees au collisionneur LEP, la ou des electrons et des positrons sont acceleres jusqu'a une energie commune, sqrt{s} = {rm E_ {cm}}, voisine de l'energie de production du rm Z^0, M_{Z ^0} egale a 91.3 GeV. La theorie electrofaible precise la direction du spin, c'est-a-dire la polarisation, d'un quark etrange primaire provenant de la desintegration d'un Z ^0. Quant a lui, le modele des quarks etablit que l'orientation du spin d'un Lambda est directement reliee a la polarisation du quark etrange dont il provient. La question est de determiner dans quelle mesure la polarisation du quark primaire est transmise au Lambda a la suite du processus de l'hadronisation, decrit dans le cadre de la ChromoDynamique Quantique. Une estimation, qui tient compte de tous ces differents aspects theoriques, evalue a 30% la polarisation des Lambda dont l'impulsion est superieure a 15 GeV/c. La mesure experimentale de la polarisation repose sur l'identification des Lambda a partir de la reconstitution de la desintegration Lambdato ppi^-. Ce processus, qui se deroule par le biais de l'interaction faible, viole la parite car

  2. Réformes Des Programmes Scolaires Et Acquisitions Á L'école Primaire En Afrique: Mythes Et Réalités

    NASA Astrophysics Data System (ADS)

    Bernard, Jean-Marc; Nkengne Nkengne, Alain Patrick; Robert, François

    2007-11-01

    SCHOOL CURRICULA REFORMS IN PRIMARY SCHOOLS IN AFRICA: MYTH VS. REALITY - This paper proposes a critical analysis of the introduction and implementation of new school curricula in Africa based on the example of the skills based approach (SBA). In many countries, the SBA has been chosen as the most appropriate and relevant method to change their school curriculum and improve education quality. We analyse the implementation of those new curricula based on the SBA in primary schools in Mauritania. The results show that the main problems affecting pupils' achievement lie rather in the effective implementation of curricula in the classrooms than in their contents. Additional analyses show that this result is confirmed in other African countries. As a background analysis, we present the origins of SBA, define its purposes and assess its limits from a pedagogical point of view. The weaknesses of this approach in taking into account the needs and the realities of African educational systems are stressed. These various elements lead to the conclusion that if curriculum reforms are often necessary in African countries, this can not be a cure for education quality issues.

  3. 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; ...

  4. 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…

  5. 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

  6. Caractérisation des paragenèses et des paléocirculations fluides dans l'indice d'or de Bleïda (Anti-Atlas, Maroc)Characterization of the paragenesis and the fluid palaeo-circulations in the gold showings of Bleida (Anti-Atlas, Morocco)

    NASA Astrophysics Data System (ADS)

    Barakat, Ahmed; Marignac, Christian; Boiron, Marie-Christine; Bouabdelli, Mohamed

    2002-01-01

    The gold showings at Bleida are hosted in Late Pan-African N50-80 °E quartz-hematite-chlorite 1 tension lenses that are related to the activity of major sinistral sub-east-west thrusts. Ores result from three superimposed stages of fluid migration. Gold occurs in microcracks offsetting the earlier minerals. Fluids evolved from COHN compositions with a saline component to boiling aqueous fluids. Pressure and temperature decreased from 50 MPa and 300 °C to less than 4 MPa and 150 °C. Thus, the gold showings at Bleida were formed in a typical geothermal (epithermal) setting, likely controlled by the Late Pan-African magmatism. To cite this article: A. Barakat et al., C. R. Geoscience 334 (2002) 35-41

  7. 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.

  8. Amniotic fluid

    MedlinePlus

    Amniotic fluid is a clear, slightly yellowish liquid that surrounds the unborn baby (fetus) during pregnancy. It is ... in the womb, the baby floats in the amniotic fluid. The amount of amniotic fluid is greatest at ...

  9. 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

  10. Amniotic fluid

    MedlinePlus

    ... page: //medlineplus.gov/ency/article/002220.htm Amniotic fluid To use the sharing features on this page, please enable JavaScript. Amniotic fluid is a clear, slightly yellowish liquid that surrounds ...

  11. 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)

  12. 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

  13. 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.

  14. 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

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

    NASA Astrophysics Data System (ADS)

    Gomez, Luis Fernando

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

  16. Amputation des quatre membres

    PubMed Central

    Feruzi, Maruis Kitembo; Milindi, Cédrick Sangwa; Zabibu, Mireille Kakinga; Mulefu, Jules Panda; Katombe, Francois Tshilombo

    2014-01-01

    Les auteurs présentent les cas d'amputation des quatre membres réalisée chez trois patients différents. Ce sont des amputations réalisées pour chaque patient au cours d'une seule hospitalisation et en un seul temps opératoire. Deux patients pour gangrène sèche infectée et un pour amputation traumatique des quatre membres. L'amputation d'urgence a été pratiquée en premier temps suivie de remodelage des moignons d'amputation en second temps. L’évolution de tous les patients a été bonne. PMID:25469177

  17. Spacer fluids

    SciTech Connect

    Wilson, W.N.; Bradshaw, R.D.; Wilton, B.S.; Carpenter, R.B.

    1992-05-19

    This patent describes a method for cementing a wellbore penetrating an earth formation into which a conduit extends, the wellbore having a space occupied by a drilling fluid. It comprises displacing the drilling fluid from the space with a spacer fluid comprising: sulfonated styrene-maleic anhydride copolymer, bentonite, welan gum, surfactant and a weighting agent; and displacing the spacer composition and filling the wellbore space with a settable cement composition.

  18. Analyse Des Inégalités De Rendement Liées Au Sexe De l'élève Dans l'Enseignement Primaire Ivoirien

    NASA Astrophysics Data System (ADS)

    Grisay, Aletta

    1984-03-01

    A survey of achievement in primary education in the Ivory Coast shows that the results of girls are inferior to those of boys in all subjects and at all levels of schooling. Concerning the learning of French (the language of instruction in the Ivory Coast), the situation differs from that observed in a number of industrialised countries, where the performance of girls is generally superior to that of boys in subjects linked to language learning. On the other hand, it conforms to the situation observed in other developing countries, where boys most frequently show superior results. This pattern of results suggests that the differences in achievement between the sexes are of a cultural origin. Analysis of factors associated with these differences in the Ivory Coast seems to confirm this hypothesis: First, society in the Ivory Coast attaches less importance to the educational achievements of girls than of boys. Girls go to school less often than boys or leave school more readily than boys. They less often express the desire to continue their studies beyond the primary school.

  19. Les neuropeptides gastro-intestinaux cibles des effets des rayonnements ionisants : altérations fonctionnelles

    NASA Astrophysics Data System (ADS)

    Linard, C.; Esposito, V.; Wysocki, J.; Griffiths, N. M.

    1998-04-01

    The symptoms associated with exposure to ionizing radiation are nausea, vomiting, diarrhoea. The response of the gut is complex involving modifications of motility and fluid and electrolyte transport. Gastrointestinal regulatory peptides have an important role in these functions. This study showed that radiation-induced tissue variations of neuropeptides have some repercussions on intestinal biological activity of these peptides soon after irradiation. In addition such modifications are also seen a few years after irradiation. Les symptômes associés à l'exposition aux rayonnements ionisants sont des nausées, vomissements et diarrhées. La réponse du système digestif est complexe, impliquant des modifications de la motilité et du transport d'eau et d'électrolytes. les neuropeptides gastro-intestinaux ont un rôle important dans ces fonctions. Cette étude montre que les variations tissulaires de ces neuropeptides induites par l'irradiation ont des répercussions sur l'activité biologique intestinale pour des temps précoces mais que ces perturbations sont encore visibles quelques années après l'irradiation.

  20. Fluid inflation

    SciTech Connect

    Chen, X.; Firouzjahi, H.; Namjoo, M.H.; Sasaki, M. E-mail: firouz@ipm.ir E-mail: misao@yukawa.kyoto-u.ac.jp

    2013-09-01

    In this work we present an inflationary mechanism based on fluid dynamics. Starting with the action for a single barotropic perfect fluid, we outline the procedure to calculate the power spectrum and the bispectrum of the curvature perturbation. It is shown that a perfect barotropic fluid naturally gives rise to a non-attractor inflationary universe in which the curvature perturbation is not frozen on super-horizon scales. We show that a scale-invariant power spectrum can be obtained with the local non-Gaussianity parameter f{sub NL} = 5/2.

  1. 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

  2. Fluid Shifts

    NASA Technical Reports Server (NTRS)

    Stenger, Michael B.; Hargens, Alan R.; Dulchavsky, Scott A.; Ebert, Douglas J.; Lee, Stuart M. C.; Laurie, Steven S.; Garcia, Kathleen M.; Sargsyan, Ashot E.; Martin, David S.; Liu, John; Macias, Brandon R.; Arbeille, Philippe; Danielson, Richard; Chang, Douglas; Gunga, Hanns-Christian; Johnston, Smith L.; Westby, Christian M.; Ploutz-Snyder, Robert J.; Smith, Scott M.

    2016-01-01

    We hypothesize that microgravity-induced cephalad fluid shifts elevate intracranial pressure (ICP) and contribute to VIIP. We will test this hypothesis and a possible countermeasure in ISS astronauts.

  3. Hyperplasie congénitale des surrénales à révélation tardive: à propos d'un cas rare

    PubMed Central

    Jayi, Sofia; Fdili, Fatima Zahra; Bouguern, Hakima; Chaara, Hekmat; Melhouf, Abdelilah

    2013-01-01

    L'hyperplasie congénitale des surrénales (HCS) par déficit en 21 hydroxylase à révélation tardive est une maladie à transmission autosomique récessive dont la présentation usuelle est une virilisation tardive para ou post pubertaire. Nous rapportons le cas d'une patiente âgée de 17 ans, ayant consulté pour aménorrhée primaire, chez qui l'examen clinique a trouvé un morphotype masculin, des signes de virilisation, des caractères sexuels secondaires présents avec une hypertrophie péniforme du clitoris. L’échographie pelvienne a confirmé la présence de l'utérus et des ovaires et a éliminé une cause tumorale ovarienne. Le dosage du sulfate de DHA (1145 ug/dl) et la 17 OH progestérone à 49,6 ng/ml étant élevés, ont orienté le diagnostic vers l'hyperplasie congénitale des surrénales à révélation tardive par déficit partiel en 21 hydroxylase. La TDM abdominale a trouvé une hypertrophie homogène bilatérale des surrénales. La patiente a été mise sous déxaméthasone 0,5 mg/ j avec déclenchement des cycles menstruels au bout de 4 mois de traitement. Une plastie clitoridienne ainsi qu'une étude moléculaire génétique étaient prévues mais la patiente était perdue de vue. A travers cette observation, et à la lumière d'une revue de la littérature, nous insistons sur les caractéristiques cliniques et para cliniques de cette entité, ainsi que l'intérêt du diagnostic précoce pour permettre une croissance normale, une puberté féminine et une fertilité satisfaisante. PMID:23819007

  4. 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

  5. Wellbore fluid

    SciTech Connect

    Swanson, B.L.

    1984-06-19

    The water loss properties of well completion and well workover fluids are improved by the addition of an effective amount of at least one adjuvant selected from (1) sodium carbonate with either sodium bicarbonate or an organic polycarboxylic acid or polycarboxylic acid anhydride or (2) sodium bicarbonate alone. In another embodiment, the adjuvants are added to stabilize water loss control agents in wellbore fluids, especially at elevated temperatures.

  6. 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.

  7. 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

  8. 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.

  9. 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

  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, 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

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

    PubMed Central

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

    2015-01-01

    Résumé Objectif Déterminer la prévalence de certaines maladies chroniques parmi les nouveaux 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 et juin 2014. Principaux paramètres à l’étude Données démographiques (âge, sexe et pays de naissance); prévalence de résultats anormaux au test Pap, d’anémie, d’élévation de la tension artérielle (TA) et de présence de marqueurs de prédiabète ou de diabète (glycémie aléatoire, glycémie à jeun ou taux d’hémoglobine A1c élevés). Résultats Plus de la moitié de nos patients étaient des femmes (56 %) et l’âge médian était de 29 ans. Les réfugiés étaient nés dans 87 pays différents. Les pays d’origine du plus grand nombre de réfugiés étaient la Hongrie (210 patients), la Corée du Nord (119 patients) et le Nigéria (93 patients). La plupart des patients sont arrivés à titre de demandeurs d’asile (92 %) plutôt qu’à titre de réfugiés pris en charge par le gouvernement (5 %). Dans l’ensemble, 11 % des patientes ayant subi un test Pap ont obtenu des résultats de cytologie cervicale anormaux, ce taux étant le plus élevé parmi les patientes originaires d’Asie (26 %; p = 0,028). La prévalence d’anémie parmi les enfants de moins de 15 ans était de 11 %; et elle était de 14 % parmi les enfants de moins de 5 ans. Environ 25 % des femmes de plus de 15 ans étaient anémiques, ce taux était le plus élevé parmi les patientes originaires d’Afrique (37 %; p < 0,001). L’élévation de la TA a été observée chez 30 % des adultes de plus de 15 ans, ce taux étant supérieur parmi les patients de sexe masculin (38 %; p < 0,001) et originaires d’Europe (42 %; p < 0,001). Les marqueurs biologiques

  13. 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.

  14. 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.

  15. 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.

  16. Cerebrospinal fluid.

    PubMed

    Jerrard, D A; Hanna, J R; Schindelheim, G L

    2001-08-01

    A quick and accurate diagnosis of maladies affecting the central nervous system (CNS) is imperative. Procurement and analysis of cerebrospinal fluid (CSF) are paramount in helping the clinician determine a patient's clinical condition. Various staining methods, measurement of white blood cell counts, glucose and protein levels, recognition of xanthochromia, and microbiologic studies are CSF parameters that are collectively important in the ultimate determination by a clinician of the presence or absence of a catastrophic CNS condition. Many of these CNS parameters have significant limitations that should be recognized to minimize under treating patients with catastrophic illness. PMID:11489408

  17. Peritoneal Fluid Analysis

    MedlinePlus

    ... limited. Home Visit Global Sites Search Help? Peritoneal Fluid Analysis Share this page: Was this page helpful? Formal name: Peritoneal Fluid Analysis Related tests: Pleural Fluid Analysis , Pericardial Fluid ...

  18. Pleural Fluid Analysis Test

    MedlinePlus

    ... limited. Home Visit Global Sites Search Help? Pleural Fluid Analysis Share this page: Was this page helpful? Formal name: Pleural Fluid Analysis Related tests: Pericardial Fluid Analysis , Peritoneal Fluid ...

  19. Gyroelastic fluids

    SciTech Connect

    Kerbel, G.D.

    1981-01-20

    A study is made of a scale model in three dimensions of a guiding center plasma within the purview of gyroelastic (also known as finite gyroradius-near theta pinch) magnetohydrodynamics. The (nonlinear) system sustains a particular symmetry called isorrhopy which permits the decoupling of fluid modes from drift modes. Isorrhopic equilibria are analyzed within the framework of geometrical optics resulting in (local) dispersion relations and ray constants. A general scheme is developed to evolve an arbitrary linear perturbation of a screwpinch equilibrium as an invertible integral transform (over the complete set of generalized eigenfunctions defined naturally by the equilibrium). Details of the structure of the function space and the associated spectra are elucidated. Features of the (global) dispersion relation owing to the presence of gyroelastic stabilization are revealed. An energy principle is developed to study the stability of the tubular screwpinch.

  20. Fluid channeling system

    NASA Technical Reports Server (NTRS)

    Davis, Donald Y. (Inventor); Hitch, Bradley D. (Inventor)

    1994-01-01

    A fluid channeling system includes a fluid ejector, a heat exchanger, and a fluid pump disposed in series flow communication The ejector includes a primary inlet for receiving a primary fluid, and a secondary inlet for receiving a secondary fluid which is mixed with the primary fluid and discharged therefrom as ejector discharge. Heat is removed from the ejector discharge in the heat exchanger, and the heat exchanger discharge is compressed in the fluid pump and channeled to the ejector secondary inlet as the secondary fluid In an exemplary embodiment, the temperature of the primary fluid is greater than the maximum operating temperature of a fluid motor powering the fluid pump using a portion of the ejector discharge, with the secondary fluid being mixed with the primary fluid so that the ejector discharge temperature is equal to about the maximum operating temperature of the fluid motor.

  1. 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.

  2. 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

  3. 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.

  4. 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.

  5. Vecteurs Singuliers des Theories des Champs Conformes Minimales

    NASA Astrophysics Data System (ADS)

    Benoit, Louis

    En 1984 Belavin, Polyakov et Zamolodchikov revolutionnent la theorie des champs en explicitant une nouvelle gamme de theories, les theories quantiques des champs bidimensionnelles invariantes sous les transformations conformes. L'algebre des transformations conformes de l'espace-temps presente une caracteristique remarquable: en deux dimensions elle possede un nombre infini de generateurs. Cette propriete impose de telles conditions aux fonctions de correlations qu'il est possible de les evaluer sans aucune approximation. Les champs des theories conformes appartiennent a des representations de plus haut poids de l'algebre de Virasoro, une extension centrale de l'algebre conforme du plan. Ces representations sont etiquetees par h, le poids conforme de leur vecteur de plus haut poids, et par la charge centrale c, le facteur de l'extension centrale, commune a toutes les representations d'une meme theorie. Les theories conformes minimales sont constituees d'un nombre fini de representations. Parmi celles-ci se trouvent des theories unitaires dont les representation forment la serie discrete de l'algebre de Virasoro; leur poids h a la forme h_{p,q}(m)=[ (p(m+1) -qm)^2-1] (4m(m+1)), ou p,q et m sont des entiers positifs et p+q<= m+1. L'entier m parametrise la charge centrale: c(m)=1 -{6over m(m+1)} avec n>= 2. Ces representations possedent un sous-espace invariant engendre par deux sous-representations avec h_1=h_{p,q} + pq et h_2=h_{p,q} + (m-p)(m+1-q) dont chacun des vecteurs de plus haut poids portent le nom de vecteur singulier et sont notes respectivement |Psi _{p,q}> et |Psi_{m-p,m+1-q}>. . Les theories super-conformes sont une version super-symetrique des theories conformes. Leurs champs appartiennent a des representation de plus haut poids de l'algebre de Neveu-Schwarz, une des deux extensions super -symetriques de l'algebre de Virasoro. Les theories super -conformes minimales possedent la meme structure que les theories conformes minimales. Les representations

  6. Joint fluid Gram stain

    MedlinePlus

    Gram stain of joint fluid ... A sample of joint fluid is needed. The fluid sample is sent to a lab where a small drop is placed in a ... on how to prepare for the removal of joint fluid, see joint fluid aspiration .

  7. 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.

  8. Ciliary fluid transport enhanced by viscoelastic fluid

    NASA Astrophysics Data System (ADS)

    Guo, Hanliang; Kanso, Eva

    2015-11-01

    Motile cilia encounter complex, non-Newtonian fluids as they beat to gain self-propulsion of cells, transport fluids, and mix particles. Recently there have been many studies on swimming in complex fluids, both experimentally and theoretically. However the role of the non-Newtonian fluid in the ciliary transport system remains largely unknown. Here we use a one-way-coupled immersed boundary method to evaluate the impacts of viscoelastic fluid (Oldroyd-B fluid) on the fluid transport generated by an array of rabbit tracheal cilia beating in a channel at low Reynolds number. Our results show that the viscoelasticity could enhance the fluid transport generated by the rabbit tracheal cilia beating pattern and the flow is sensitive to the Deborah number in the range we investigate.

  9. Synovial fluid analysis

    MedlinePlus

    Joint fluid analysis; Joint fluid aspiration ... El-Gabalawy HS. Synovial fluid analysis, synovial biopsy, and synovial pathology. In: Firestein GS, Budd RC, Gabriel SE, McInnes IB, O'Dell JR, eds. Kelly's Textbook of ...

  10. Pleural fluid Gram stain

    MedlinePlus

    Gram stain of pleural fluid ... lungs fill a person's chest with air. If fluid builds up in the space outside the lungs ... chest, it can cause many problems. Removing the fluid can relieve a person's breathing problems and help ...

  11. Pericardial fluid culture

    MedlinePlus

    Culture - pericardial fluid ... the heart (the pericardium). A small amount of fluid is removed. You may have an ECG and ... x-ray after the test. Sometimes the pericardial fluid is taken during open heart surgery. The sample ...

  12. Pleural fluid culture

    MedlinePlus

    Culture - pleural fluid ... is used to get a sample of pleural fluid. The sample is sent to a laboratory and ... the chest wall into the pleural space. As fluid drains into a collection bottle, you may cough ...

  13. 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.

  14. Fluid sampling device

    NASA Technical Reports Server (NTRS)

    Studenick, D. K. (Inventor)

    1977-01-01

    An inlet leak is described for sampling gases, more specifically, for selectively sampling multiple fluids. This fluid sampling device includes a support frame. A plurality of fluid inlet devices extend through the support frame and each of the fluid inlet devices include a longitudinal aperture. An opening device that is responsive to a control signal selectively opens the aperture to allow fluid passage. A closing device that is responsive to another control signal selectively closes the aperture for terminating further fluid flow.

  15. 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

  16. 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. PMID:23005525

  17. 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.

  18. 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.

  19. 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).

  20. 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).

  1. 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).

  2. 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).

  3. 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).

  4. 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).

  5. 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 .

  6. 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 ...

  7. 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 .

  8. 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.

  9. Amniotic fluid (image)

    MedlinePlus

    Amniotic fluid surrounds the growing fetus in the womb and protects the fetus from injury and temperature changes. It ... fetal movement and permits musculoskeletal development. The amniotic fluid can be withdrawn in a procedure called amniocentsis ...

  10. Fluid and Electrolyte Balance

    MedlinePlus

    ... They are in your blood, urine and body fluids. Maintaining the right balance of electrolytes helps your ... them from the foods you eat and the fluids you drink. Levels of electrolytes in your body ...

  11. 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.

  12. 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.

  13. 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.

  14. 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 ...

  15. Amniotic fluid (image)

    MedlinePlus

    Amniotic fluid surrounds the growing fetus in the womb and protects the fetus from injury and temperature changes. ... of fetal movement and permits musculoskeletal development. The amniotic fluid can be withdrawn in a procedure called amniocentsis ...

  16. 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.

  17. 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,…

  18. Aqueous drilling fluids containing fluid loss additives

    SciTech Connect

    Bardoliwalla, D.F.; Villa, J.L.

    1987-03-03

    This patent describes an aqueous clay containing drilling fluid having present in an amount sufficient to reduce fluid loss of the drilling fluid, a copolymer of (1) from about 80% to about 98% by weight of acrylic acid and (2) from about 2% to about 20% by weight of itaconic acid. The copolymer has a weight average molecular weight of between about 50,000 to about 1,000,000, being in its free acid or partially or completely neutralized salt form and being at least water dispersible.

  19. Fluid inclusion geothermometry

    USGS Publications Warehouse

    Cunningham, C.G., Jr.

    1977-01-01

    Fluid inclusions trapped within crystals either during growth or at a later time provide many clues to the histories of rocks and ores. Estimates of fluid-inclusion homogenization temperature and density can be obtained using a petrographic microscope with thin sections, and they can be refined using heating and freezing stages. Fluid inclusion studies, used in conjunction with paragenetic studies, can provide direct data on the time and space variations of parameters such as temperature, pressure, density, and composition of fluids in geologic environments. Changes in these parameters directly affect the fugacity, composition, and pH of fluids, thus directly influencing localization of ore metals. ?? 1977 Ferdinand Enke Verlag Stuttgart.

  20. Fluid cooled electrical assembly

    SciTech Connect

    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.

  1. 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.

  2. Annuaire du Bureau des longitudes - 2006

    NASA Astrophysics Data System (ADS)

    Imcce; Bureau Des Longitudes

    2005-07-01

    This annual publication provides ephemerides and data to the use of professionnal and amateur astronomers. Divided in 11 chapters it covers concordance of various calendars, explanation of fondamental astronomy and various time scales, explanation for the use of ephemerides; tables provide ephemerides (positions, rise/set/passage) of the Sun and the Moon, planets, planetary satellites, asteroids, comets, bright stars; data and explanation for the physical observation of the surface of the Sun, the Moon, and planets; chart of the sky and a list of constellations and galaxies; prediction and ephemerides for astronomical phenomenon: occultation by the moon, stellar occultations by asteroids and appulses, solar eclipses and lunar eclipses; and an additional review about a hot scientific topic, this year: "Legendre et le méridien terrestre, 200 ans après". Cette publication annuelle fournit des éphémérides et des données à l'usage des astronomes professionnels et des astronomes amateurs. Composée de 11 chapitres elle comprend les rubriques sur les différents calendriers et leurs concordance, les fêtes légales en France, les dates et décrets sur les heures légales en France métropolitaine ; une introduction à l'astronomie fondamentale et aux différentes échelles de temps, des explications sur l'utilisation des éphémérides ; des tables fournissent les éphémérides (positions, heures de lever/coucher/passage) du Soleil et de la Lune, de planètes, de satellites naturels, d'astéroïdes, de comètes, d'étoiles brillantes ; des données pour l'observation de la surface du Soleil, de la Lune, et des planètes ; des cartes du ciel ainsi qu'une liste de constellations et de galaxies ; des prédictions des phénomènes astronomiques : occultation par la Lune, occultation stellaires par des astéroïdes et appulses, éclipses de Soleil et de la Lune; la liste et les coordonnées des observatoires astronomiques les plus connus ; et enfin un cahier th

  3. 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

  4. 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.

  5. 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. PMID:22432584

  6. 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.

  7. 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.

  8. 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.

  9. 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.

  10. 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. PMID:18655997

  11. 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.

  12. Fluid inclusion petrography

    NASA Astrophysics Data System (ADS)

    Van den Kerkhof, Alfons M.; Hein, Ulrich F.

    2001-01-01

    A procedure of fluid inclusion studies is proposed with emphasis on the criteria of selecting fluid inclusions for detailed (microthermometry and spectroscopic) analysis. An overview of descriptive and genetic classifications of fluid inclusions in single crystals and in massive rocks is given with the intention of further differentiating the commonly used terms 'primary' and 'secondary' fluid inclusions. Some principles of fluid inclusion modification are explained. Cathodoluminescence (CL) studies of quartz with the optical high-power CL-microscope and the electron microprobe provided with a CL detector are an important help in 'fluid petrography'. CL textures are subdivided in primary, growth textures and a wide variety of secondary microtextures, which are in part induced by fluid inclusions. The latter is grouped in textures indicative of local lower crystal order (increasing defect structures) and microtextures indicative of local quartz healing (reduction of the defect structures). Microtextures showing the genetic relationship between fluid inclusions and the host mineral provide information about the possible post-entrapment changes of fluid inclusions and therewith testify their geological relevance.

  13. 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.

  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. Electrodeposition from supercritical fluids.

    PubMed

    Bartlett, P N; Cook, D A; George, M W; Hector, A L; Ke, J; Levason, W; Reid, G; Smith, D C; Zhang, W

    2014-05-28

    Recent studies have shown that it is possible to electrodeposit a range of materials, such as Cu, Ag and Ge, from various supercritical fluids, including hydrofluorocarbons and mixtures of CO2 with suitable co-solvents. In this perspective we discuss the relatively new field of electrodeposition from supercritical fluids. The perspective focuses on some of the underlying physical chemistry and covers both practical and scientific aspects of electrodeposition from supercritical fluids. We also discuss possible applications for supercritical fluid electrodeposition and suggest some key developments that are required to take the field to the next stage. PMID:24469309

  16. Electrorheological fluids and methods

    SciTech Connect

    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.

  17. How to Avoid Fluid Overload

    PubMed Central

    Ogbu, Ogbonna C.; Murphy, David J.; Martin, Greg S.

    2015-01-01

    Purpose of the review This review highlights recent evidence describing the outcomes associated with fluid overload in critically ill patients and provides an overview of fluid management strategies aimed at preventing fluid overload during the resuscitation of patients with shock. Recent findings Fluid overload is a common complication of fluid resuscitation and is associated with increased hospital costs, morbidity and mortality. Summary Fluid management goals differ during the resuscitation, optimization, stabilization and evacuation phases of fluid resuscitation. To prevent fluid overload, strategies that reduce excessive fluid infusions and emphasize the removal of accumulated fluids should be implemented. PMID:26103147

  18. Aqueous drilling fluids containing fluid loss additives

    SciTech Connect

    Bardoliwalla, D.F.; Villa, J.L.

    1986-11-11

    This patent describes a copolymer of (1) from about 80% to about 98% by weight of acrylic acid and (2) from about 2% to about 20% by weight of itaconic acid. The copolymer has a weight average molecular weight of between about 1000,000 to about 1,000,000, is in the form of its free acid or partially or completely sodium, potassium or ammonium neutralized salt and is at least water dispersible. The partially neutralized salt is prepared by reacting carboxylic groups present in the acrylic acid and the itaconic acid with neutralizing agent, the copolymer being useful as a fluid loss control additive for aqueous drilling fluids.

  19. 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.

  20. FLUID CONTROLLING MEANS

    DOEpatents

    Pouliot, H.N.

    1960-11-01

    A device is described for releasing fluid from a container and delivering it to an outlet conduit. An explosive squib moves a piston so as to cut a wall section from the conduit and to punch a hole in the container, whereby a fluid may pass from the container into the conduit. A deformable sleeve retains the piston in its final position.

  1. 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)

  2. 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.

  3. Solar heat transport fluid

    NASA Technical Reports Server (NTRS)

    1978-01-01

    The progress made in the development and delivery of noncorrosive fluid subsystems is discussed. 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. The performance testing of a number of fluids is described.

  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. Computational fluid dynamics

    NASA Technical Reports Server (NTRS)

    1989-01-01

    An overview of computational fluid dynamics (CFD) activities at the Langley Research Center is given. The role of supercomputers in CFD research, algorithm development, multigrid approaches to computational fluid flows, aerodynamics computer programs, computational grid generation, turbulence research, and studies of rarefied gas flows are among the topics that are briefly surveyed.

  6. 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.

  7. 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.

  8. 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.…

  9. 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.

  10. Fluid blade disablement tool

    DOEpatents

    Jakaboski, Juan-Carlos; Hughs, Chance G.; Todd, Steven N.

    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.

  11. 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.

  12. 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.

  13. 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.

  14. 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.

  15. 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.

  16. 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.

  17. Fluid-driven metamorphism

    NASA Astrophysics Data System (ADS)

    Jamtveit, B.; Ulven, O. I.; Malthe-Sorenssen, A.

    2014-12-01

    Metamorphic processes in the Earth crust are almost invariably associated with fluid migration. Many lines of evidence suggest that fluid migration is intimately coupled both to the metamorphic reactions, and to associated deformation processes. Petrologic arguments suggest that all granulite facies and most amphibolite facies rocks are essentially dry (no free fluid phase) at normal geothermal gradients outside periods of heating-produced fluid generation. In addition, except at high pressure - low temperature condition, fluid-consuming reactions leads to an increase in solid volume and a potential clogging of any initial pore space. Hence, fluid migration in medium and high-grade metamorphic rocks is in general associated with some porosity producing process. Porosity generation may occur by either chemical or mechanical processes. In systems with high fluid fluxes, porosity may be produced by dissolution and transport of mass out of the system. Such fluxes can normally only be sustained over short length scales and limited time scales. In systems where the infiltrating fluid is far from equilibrium with the rock matrix, mechanical porosity generation can arise from local stresses generated by the volume change of volatilization reactions. Furthermore, it has become increasingly clear that crustal rocks may be under significant tectonic stress, even far from plate tectonic boundaries. In situations where the rocks are close to critically stressed, any stress perturbations caused by reaction driven changes in solid volume or fluid pressure gradients may lead to dilatant deformation and porosity production on a scale much larger than the characteristic length scales of the reacting rock units. Field observations, experimental studies and modeling results will be presented that focus on reaction driven porosity generation in systems subject to variable initial differential stresses.

  18. Multiphase fluid characterization system

    DOEpatents

    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.

  19. 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.

  20. 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.

  1. 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.

  2. 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.

  3. Space Station fluid resupply

    NASA Technical Reports Server (NTRS)

    Winters, AL

    1990-01-01

    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.

  4. Relativistic fluid dynamics. Proceedings.

    NASA Astrophysics Data System (ADS)

    Anile, A. M.; Choquet-Bruhat, Y.

    Contents: 1. Covariant theory of conductivity in ideal fluid or solid media (B. Carter). 2. Hamiltonian techniques for relativistic fluid dynamics and stability theory (D. D. Holm). 3. Covariant fluid mechanics and thermodynamics: an introduction (W. Israel). 4. Relativistic plasmas (H. Weitzner). 5. An improved relativistic warm plasma model (A. M. Anile, S. Pennisi). 6. Relativistic extended thermodynamics II (I. Müller). 7. Relativistic extended thermodynamics: general assumptions and mathematical procedure (T. Ruggeri). 8. Relativistic hydrodynamics and heavy ion reactions (D. Strottman). 9. Some problems in relativistic hydrodynamics (C. G. van Weert).

  5. Synthetic Base Fluids

    NASA Astrophysics Data System (ADS)

    Brown, M.; Fotheringham, J. D.; Hoyes, T. J.; Mortier, R. M.; Orszulik, S. T.; Randles, S. J.; Stroud, P. M.

    The chemical nature and technology of the main synthetic lubricant base fluids is described, covering polyalphaolefins, alkylated aromatics, gas-to-liquid (GTL) base fluids, polybutenes, aliphatic diesters, polyolesters, polyalkylene glycols or PAGs and phosphate esters.Other synthetic lubricant base oils such as the silicones, borate esters, perfluoroethers and polyphenylene ethers are considered to have restricted applications due to either high cost or performance limitations and are not considered here.Each of the main synthetic base fluids is described for their chemical and physical properties, manufacture and production, their chemistry, key properties, applications and their implications when used in the environment.

  6. 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)

  7. Pleural fluid analysis

    MedlinePlus

    ... cleans the skin around the insertion site. Numbing medicine (anesthetic) is injected into the skin. A needle is placed through the skin and muscles of the chest wall into the pleural space. As fluid drains into a collection bottle, you ...

  8. Lighter fluid poisoning

    MedlinePlus

    ... the person swallowed the lighter fluid, give them water or milk right away, if a provider tells you to do so. ... Fillmore Suburban Hospital, Buffalo, NY. Also reviewed by David Zieve, MD, MHA, ...

  9. 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.

  10. 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.

  11. Computational fluid dynamic control

    NASA Technical Reports Server (NTRS)

    Hartley, Tom T.; Deabreu-Garcia, Alex

    1989-01-01

    A general technique is presented for modeling fluid, or gas, dynamic systems specifically for the development of control systems. The numerical methods which are generally used in computational fluid dynamics are borrowed to create either continuous-time or discrete-time models of the particular fluid system. The resulting equations can be either left in a nonlinear form, or easily linearized about an operating point. As there are typically very many states in these systems, the usual linear model reduction methods can be used on them to allow a low-order controller to be designed. A simple example is given which typifies many internal flow control problems. The resulting control is termed computational fluid dynamic control.

  12. 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 ...

  13. 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...

  14. Cerebrospinal fluid culture

    MedlinePlus

    ... is a laboratory test to look for bacteria, fungi, and viruses in the normally clear fluid that ... The laboratory personnel watch to see if bacteria, fungi, or viruses grow in the dish. Growth means ...

  15. Joint fluid Gram stain

    MedlinePlus

    Gram stain of joint fluid ... result means no bacteria are present on the Gram stain. Normal value ranges may vary slightly among ... Abnormal results mean bacteria were seen on the Gram stain. This may be a sign of a ...

  16. Lighter fluid poisoning

    MedlinePlus

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

  17. 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)

  18. 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.

  19. Peritoneal fluid analysis

    MedlinePlus

    ... people who have liver disease See whether an injury to the abdomen has caused internal bleeding ... fluid may be a sign of tumor or injury. High white blood cell ... the abdomen. Large differences between the amount of albumin in ...

  20. 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.

  1. Valve for fluid control

    DOEpatents

    Oborny, Michael C.; Paul, Phillip H.; Hencken, Kenneth R.; Frye-Mason, Gregory C.; Manginell, Ronald P.

    2001-01-01

    A valve for controlling fluid flows. This valve, which includes both an actuation device and a valve body provides: the ability to incorporate both the actuation device and valve into a unitary structure that can be placed onto a microchip, the ability to generate higher actuation pressures and thus control higher fluid pressures than conventional microvalves, and a device that draws only microwatts of power. An electrokinetic pump that converts electric potential to hydraulic force is used to operate, or actuate, the valve.

  2. 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.

  3. Fluid property measurements study

    NASA Technical Reports Server (NTRS)

    Devaney, W. E.

    1976-01-01

    Fluid properties of refrigerant-21 were investigated at temperatures from the freezing point to 423 Kelvin and at pressures to 1.38 x 10 to the 8th power N/sq m (20,000 psia). The fluid properties included were: density, vapor pressure, viscosity, specific heat, thermal conductivity, thermal expansion coefficient, freezing point and bulk modulus. Tables of smooth values are reported.

  4. [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. PMID:24467958

  5. 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. PMID:27112279

  6. Thermostating highly confined fluids.

    PubMed

    Bernardi, Stefano; Todd, B D; Searles, Debra J

    2010-06-28

    In this work we show how different use of thermostating devices and modeling of walls influence the mechanical and dynamical properties of confined nanofluids. We consider a two dimensional fluid undergoing Couette flow using nonequilibrium molecular dynamics simulations. Because the system is highly inhomogeneous, the density shows strong fluctuations across the channel. We compare the dynamics produced by applying a thermostating device directly to the fluid with that obtained when the wall is thermostated, considering also the effects of using rigid walls. This comparison involves an analysis of the chaoticity of the fluid and evaluation of mechanical properties across the channel. We look at two thermostating devices with either rigid or vibrating atomic walls and compare them with a system only thermostated by conduction through vibrating atomic walls. Sensitive changes are observed in the xy component of the pressure tensor, streaming velocity, and density across the pore and the Lyapunov localization of the fluid. We also find that the fluid slip can be significantly reduced by rigid walls. Our results suggest caution in interpreting the results of systems in which fluid atoms are thermostated and/or wall atoms are constrained to be rigid, such as, for example, water inside carbon nanotubes. PMID:20590213

  7. The enhancement of existing DES Maplet interface

    NASA Astrophysics Data System (ADS)

    Abdullah, Nur Lina; Mutalip, Rasidah Abdull; Abdullah, Kamilah

    2014-07-01

    This study pertains to the process of Data Encryption Standard, DES. DES consists of encryption and decryption processes linked with mathematical elements such as algebra and number theory. Preliminary, studies revealed that most of mathematics students face a problem in understanding the complicated process of DES. In modern learning methods, learning environment becomes more interesting with the use of computer and a variety of mathematical software packages. Several mathematical softwares such as Maple, Mathematica, Mathlab and Sage were developed in order to fulfill the specific calculation requirements. Correspondingly, motivated from that, this study incorporated with Maple to enhance the existing DES Maplet interface to be more interactive and user-friendly compared to the original version.

  8. Copernic: la piste des influences arabes

    NASA Astrophysics Data System (ADS)

    Khalatbari, A.; Bonnet-Bidaud, J. M.

    2004-10-01

    Copernic a-t-il connu le travail des astronomes du Moyen-Orient ? S'en est-il inspiré pour élaborer sa théorie de l'héliocentrisme ? C'est l'hypothèse avancée par certains historiens des sciences pour comprendre le génie de celui qui, le premier, a placé le Soleil au centre du monde. Enquête.

  9. Inverse magnetorheological fluids.

    PubMed

    Rodríguez-Arco, L; López-López, M T; Zubarev, A Y; Gdula, K; Durán, J D G

    2014-09-01

    We report a new kind of field-responsive fluid consisting of suspensions of diamagnetic (DM) and ferromagnetic (FM) microparticles in ferrofluids. We designate them as inverse magnetorheological (IMR) fluids for analogy with inverse ferrofluids (IFFs). Observations on the particle self-assembly in IMR fluids upon magnetic field application showed that DM and FM microparticles were assembled into alternating chains oriented along the field direction. We explain such assembly on the basis of the dipolar interaction energy between particles. We also present results on the rheological properties of IMR fluids and, for comparison, those of IFFs and bidispersed magnetorheological (MR) fluids. Interestingly, we found that upon magnetic field application, the rheological properties of IMR fluids were enhanced with respect to bidispersed MR fluids with the same FM particle concentration, by an amount greater than the sum of the isolated contribution of DM particles. Furthermore, the field-induced yield stress was moderately increased when up to 30% of the total FM particle content was replaced with DM particles. Beyond this point, the dependence of the yield stress on the DM content was non-monotonic, as expected for FM concentrations decreasing to zero. We explain these synergistic results by two separate phenomena: the formation of exclusion areas for FM particles due to the perturbation of the magnetic field by DM particles and the dipole-dipole interaction between DM and FM particles, which enhances the field-induced structures. Based on the second phenomenon, we present a theoretical model for the yield stress that semi-quantitatively predicts the experimental results. PMID:25022363

  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. 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

  12. 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.

  13. Diffusion des Metaux et Evolution Stellaire

    NASA Astrophysics Data System (ADS)

    Turcotte, Sylvain

    Nous presentons dans cette these des modeles d'evolution stellaire incorporant la diffusion microscopique de maniere consistante. Pour la premiere fois, on a calcule l'evolution d'etoiles en tenant compte en detail de l'impact des variations d'abondances sur leur structure. Nous utilisons des spectres monochromatiques pour chacun des elements les plus abondants dans un melange solaire pour recalculer l'opacite pour les abondances et les conditions locales dans l'interieur d'une etoile au cours de son evolution. Nos modeles montrent que la diffusion atomique des metaux a un effet important sur les opacites dan les etoiles de plus de 1.3Msolar ou l'abondance du fer et des autres elements du pic du fer varient substantiellement. Ces etoiles, sans rotation ou champ magnetique, sont proches des etoiles de type Fm-Am dans lesquelles on observe une legere surabondance d'elements du pic du fer en plus d'une sous-abondance de calcium, sous-abondance que l'on obtient egalement. Nous obtenons cependant des surabondances depassant un facteur 10 pour les etoiles de plus de 1.4Msolar ce qui suggere qu'il existe un ou plusieurs mecanismes limitant la diffusion microscopique. La surabondance du fer en surface cause une augmentation, qui peut atteindre un facteur sept, de l'opacite a la limite de la zone convective. Ceci cause un accroissement de la temperature effective et de la masse de la zone convective comparativement aux modeles n'incluant que la diffusion de l'helium. Il s'agit la du principal effet de la diffusion sur la structure interne de ces etoiles. La diffusions n'a pas d'influence sur l'evolution de coeur stellaire dans les etoiles significativement plus massives quie le Soleil. Nous avons verife que l'utilisation de modeles consistants avec diffusion n'apporte pas d'amelioration sensible aux modeles solaires. Les forces radiatives calculees a partir des spectres d'OPAL pour les elements du pic du fer representent une fraction importante de la gravite. On obtient des

  14. 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

  15. Fluid driven recipricating apparatus

    DOEpatents

    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.

  16. Fluid driven reciprocating apparatus

    DOEpatents

    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.

  17. 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.

  18. 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.

  19. Amniotic fluid embolism.

    PubMed

    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

  20. 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.

  1. 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.

  2. 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.

  3. Stochastic interpenetration of fluids

    SciTech Connect

    Steinkamp, M.J.; Clark, T.T.; Harlow, F.H.

    1995-11-01

    We describe a spectral approach to the investigation of fluid instability, generalized turbulence, and the interpenetration of fluids across an interface. The technique also applies to a single fluid with large variations in density. Departures of fluctuating velocity components from the local mean are far subsonic, but the mean Mach number can be large. Validity of the description is demonstrated by comparisons with experiments on turbulent mixing due to the late stages of Rayleigh-Taylor instability, when the dynamics become approximately self-similar in response to a constant body force. Generic forms for anisotropic spectral structure are described and used as a basis for deriving spectrally integrated moment equations that can be incorporated into computer codes for scientific and engineering analyses.

  4. 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.

  5. Computational Fluid Dynamics

    NASA Astrophysics Data System (ADS)

    Chung, T. J.

    2002-03-01

    Computational fluid dynamics (CFD) techniques are used to study and solve complex fluid flow and heat transfer problems. This comprehensive text ranges from elementary concepts for the beginner to state-of-the-art CFD for the practitioner. It discusses and illustrates the basic principles of finite difference (FD), finite element (FE), and finite volume (FV) methods, with step-by-step hand calculations. Chapters go on to examine structured and unstructured grids, adaptive methods, computing techniques, and parallel processing. Finally, the author describes a variety of practical applications to problems in turbulence, reacting flows and combustion, acoustics, combined mode radiative heat transfer, multiphase flows, electromagnetic fields, and relativistic astrophysical flows. Students and practitioners--particularly in mechanical, aerospace, chemical, and civil engineering--will use this authoritative text to learn about and apply numerical techniques to the solution of fluid dynamics problems.

  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. Wireline fluid sampling

    SciTech Connect

    Michaels, J.; Moody, M.; Shwe, T.

    1995-12-31

    Accurate PVT data are crucial to well completion and production, formation evaluation and reservoir characterization. This is especially true for initial reservoir characterization where the PVF sample needs to be obtained prior to production. It is essential that the fluid sample be recovered as closely as possible to in-situ conditions whether by drill stem or wireline formation for. The need to remove drilling mud filtrate prior to collecting a sample has been widely recognized. Wireline testers which can pump fluid from a formation until filtrate is reduced to a minimum overcome this problem. While reducing sample contamination has been addressed, little emphasis has been placed on the need to control inlet pressure during filtrate removal or during sampling. Reducing contamination is important; however, there is equal need to determine the critical sampling pressure. The purpose is to prevent phase separation in the formation by regulating the sampling process based on this information and thereby obtain a more representative reservoir fluid sample. A recently introduced wireline instrument provides the capability of measuring the critical pressure prior to sampling, of controlling the sample pressure and of increasing the pressure in the sample container to compensate for temperature decline during delivery of that sample to a testing laboratory. Example of pressure tests while pumping and during pressure buildup are presented along with indicated sample properties. Introduction Wireline Formation Testers (WFT) provide an cost effective means to determine pressure as a function of depth and to recover samples of fluid from formations at selected depths. No other method can provide this type of information. Pressure data are used to estimate mobility, fluid contact and fluid density.

  8. Fluid therapy in calves.

    PubMed

    Smith, Geof W; Berchtold, Joachim

    2014-07-01

    Early and aggressive fluid therapy is critical in correcting the metabolic complications associated with calf diarrhea. Oral electrolyte therapy can be used with success in calves, but careful consideration should be given to the type of oral electrolyte used. Electrolyte solutions with high osmolalities can significantly slow abomasal emptying and can be a risk factor for abomasal bloat in calves. Milk should not be withheld from calves with diarrhea for more than 12 to 24 hours. Hypertonic saline and hypertonic sodium bicarbonate can be used effectively for intravenous fluid therapy on farms when intravenous catheterization is not possible. PMID:24980729

  9. High temperature drilling fluids

    SciTech Connect

    Stong, R.E.; Walinsky, S.W.

    1986-01-28

    This patent describes an aqueous drilling fluid suitable for high-temperature use. This fluid is composed of a water base. Clay is suspended in the base and from about 0.01-25 pounds per barrel total composition of a hydrolyzed terpolymer of maleic anhydride, styrene and a third monomer selected from acrylamide, methacrylamide, acrylic acid and metacrylic acid. The molar ratio of maleic anhydride to styrene to the third monomer is from about 30:10:60 to 50:40:10, and the alkali metal, ammonium and lower aliphatic amine salts thereof, the weight-average molecular weight of the hydrolyzed terpolymer is from about 500-10,000.

  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. 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.

  12. 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.

  13. 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)

  14. Relativistic viscoelastic fluid mechanics

    SciTech Connect

    Fukuma, Masafumi; Sakatani, Yuho

    2011-08-15

    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.

  15. A Fluid Block Schedule

    ERIC Educational Resources Information Center

    Ubben, Gerald C.

    1976-01-01

    Achieving flexibility without losing student accountability is a challenge that faces every school. With a fluid block schedule, as described here, accountability is maintained without inhibiting flexibility. An additional advantage is that three levels of schedule decision making take some of the pressure off the principal. (Editor)

  16. 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.

  17. Two-fluid instability

    SciTech Connect

    Stewart, H.B.

    1984-01-01

    The ability of interpenetrating flow models to represent multidimensional instabilities is probed by numerical experiments with an L-shaped two-fluid jet. Periodic and nonperiodic oscillations of various types are observed, and a partial phase portrait is constructed. The numerical experiments suggest new approaches to verifying transient interpenetrating flow models. 18 references.

  18. Environmental Fluid Dynamics Code

    EPA Science Inventory

    The Environmental Fluid Dynamics Code (EFDC)is a state-of-the-art hydrodynamic model that can be used to simulate aquatic systems in one, two, and three dimensions. It has evolved over the past two decades to become one of the most widely used and technically defensible hydrodyn...

  19. Pleural fluid culture

    MedlinePlus

    A procedure called thoracentesis is used to get a sample of pleural fluid. The sample is sent to a laboratory and examined under ... For thoracentesis, you sit on the edge of a chair or bed with your head and arms resting on ...

  20. 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.

  1. 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.

  2. 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... DRAWBRIDGE OPERATION REGULATIONS Specific Requirements Louisiana § 117.439 Des Allemands Bayou. (a) The draw of the S631 bridge, mile 13.9 at Des Allemands, shall open on signal if at least four hours notice...

  3. 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... DRAWBRIDGE OPERATION REGULATIONS Specific Requirements Louisiana § 117.439 Des Allemands Bayou. (a) The draw of the S631 bridge, mile 13.9 at Des Allemands, shall open on signal if at least four hours notice...

  4. 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... DRAWBRIDGE OPERATION REGULATIONS Specific Requirements Louisiana § 117.439 Des Allemands Bayou. (a) The draw of the S631 bridge, mile 13.9 at Des Allemands, shall open on signal if at least four hours notice...

  5. Fluid Transport in Lineaments

    NASA Astrophysics Data System (ADS)

    Kerrich, R.

    1986-04-01

    Fluid infiltration into fault zones and their deeper level counterparts, brittle-ductile shear zones, is examined in five different tectonic environments. In the 2.7 Ga Abitibi Greenstone Belt major tectonic discontinuities have lateral extents of hundreds of kilometres. These structures, initiated as listric normal faults accommodating rift extension of the greenstone belt, acted as sites for the extrusion of komatiitic magmas, and formed submarine scarps which delimit linear belts of clastic and chemical sediments. During reverse motion on the structures, accommodating shortening of the belt, these transcrustal faults were used as a conduit for the ascent of trondhjemitic magmas from the base of the crust, alkaline magmas from the asthenosphere, and for discharge of hundreds of cubic kilometres of hydrothermal fluids. Such fluids were characterized by δ 18O = 6 ± 2, δ D = -50 ± 20, δ 13C = -4 ± 3, and temperatures of 270-450 degrees C, probably derived from devolatilization of crustal rocks undergoing prograde metamorphism. Hydrothermal fluids were more radiogenic (87Sr/86Sr = 0.7010-0.7040) and possessed higher values of μ than contemporaneous mantle, komatiites or tholeiites, and thus carried a contribution from older sialic basement. Mineralized faults possess enrichments of l.i.l. elements, including K, Rb, Li, Cs, B and CO2, as well as rare elements such as Au, Ag, As, Sb, Se, Te, Bi, W. Fluids were characterized by XCO_{2}≈ 0.1, neutral to slightly acidic pH, low salinity (less than 3% by mass), and K/Na ≈ 0.1, carried minor CH4, CO and N2, and underwent transient effervescence of CO2 during decompression. At Yellowknife, a series of large-scale shear zones developed by brittle-ductile mechanisms, involving volume dilation with the migration of ca. 5% (by mass) volatiles into the shear zone from surrounding metabasalts. This early deformation involved no departures in redox state or whole-rock δ 18O from background states of Fe2+/ɛ Fe = 0.7 and

  6. 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.

  7. 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.

  8. Magnetic fluids and their applications

    NASA Astrophysics Data System (ADS)

    Saeynaetjoki, M.

    1991-02-01

    Magnetic fluids consist of carrier fluid, magnetically active particles and surfactant on each particle preventing the agglomeration of the particles. The fluids acting in the presence of the magnetic field like the ferromagnetic materials, but remaining their fluid properties, are prepared in this way. Potential applications of these fluids are magnetic separation, ink jet printing, sealing, damping, lubrication and heat transfer. So far, the industrial applications of the magnetic fluids are in the seals and bearings of the computer hard disk drives, in the heat transfer and damping of loudspeakers and in the damping of step motors. The other applications are in laboratory and research stage.

  9. The GBT-SerDes ASIC prototype

    NASA Astrophysics Data System (ADS)

    Moreira, P.; Baron, S.; Bonacini, S.; Cobanoglu, O.; Faccio, F.; Feger, S.; Francisco, R.; Gui, P.; Li, J.; Marchioro, A.; Paillard, C.; Porret, D.; Wyllie, K.

    2010-11-01

    In the framework of the GigaBit Transceiver project (GBT), a prototype, the GBT-SerDes ASIC, was developed, fabricated and tested. To sustain high radiation doses while operating at 4.8Gb/s, the ASIC was fabricated in a commercial 130 nm CMOS technology employing radiation tolerant techniques and circuits. The transceiver serializes-deserializes the data, Reed-Solomon encodes and decodes the data and scrambles and descrambles the data for transmission over optical fibre links. This paper describes the GBT-SerDes architecture, and presents the test results.

  10. 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.

  11. Magnetically stimulated fluid flow patterns

    ScienceCinema

    Martin, Jim; Solis, Kyle

    2014-08-06

    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.

  12. 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.

  13. Proctoclysis: emergency rectal fluid infusion.

    PubMed

    Tremayne, Vincent

    This article describes the use and effectiveness of proctoclysis (rectal fluid infusion) in providing fluid resuscitation in the absence of intravenous access in rural and remote environments. PMID:19856644

  14. Field theory for string fluids

    NASA Astrophysics Data System (ADS)

    Schubring, Daniel; Vanchurin, Vitaly

    2015-08-01

    We develop a field theory description of nondissipative string fluids and construct an explicit mapping between field theory degrees of freedom and hydrodynamic variables. The theory generalizes both a perfect particle fluid and pressureless string fluid to what we call a perfect string fluid. Ideal magnetohydrodynamics is shown to be an example of the perfect string fluid whose equations of motion can be obtained from a particular choice of the Lagrangian. The Lagrangian framework suggests a straightforward extension of the perfect string fluid to more general anisotropic fluids describing higher dimensional branes such as domain walls. Other modifications of the Lagrangian are discussed which may be useful in describing relativistic superfluids and fluids containing additional currents.

  15. 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.

  16. 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.

  17. Geophysical fluid dynamics

    NASA Technical Reports Server (NTRS)

    Fowlis, W. W.

    1981-01-01

    Systematic scaling or dimensional analysis reveals that certain scales of geophysical fluid flows (such as stellar, ocean, and planetary atmosphere circulations) can be accurately modeled in the laboratory using a procedure which differs from conventional engineering modeling. Rather than building a model to obtain numbers for a specific design problem, the relative effects of the significant forces are systematically varied in an attempt to deepen understanding of the effects of these forces. Topics covered include: (1) modeling a large-scale planetary atmospheric flow in a rotating cylindrical annulus; (2) achieving a radial dielectric body force; (3) spherical geophysical fluid dynamics experiments for Spacelab flights; (4) measuring flow and temperature; and (5) the possible effect of rotational or precessional disturbances on the flow in the rotating spherical containers.

  18. 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.

  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. 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.

  1. 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.

  2. Perspectives in Fluid Dynamics

    NASA Astrophysics Data System (ADS)

    Batchelor, G. K.; Moffatt, H. K.; Worster, M. G.

    2002-12-01

    With applications ranging from modelling the environment to automotive design and physiology to astrophysics, conventional textbooks cannot hope to give students much information on what topics in fluid dynamics are currently being researched, or how to choose between them. This book rectifies matters. It consists of eleven chapters that introduce and review different branches of the subject for graduate-level courses, or for specialists seeking introductions to other areas. Hb ISBN (2001): 0-521-78061-6

  3. MEMS fluid viscosity sensor.

    PubMed

    Ballato, Arthur

    2010-03-01

    Quartz shear resonators are employed widely as sensors to measure Newtonian viscosities of liquids. Perturbation of the electrical equivalent circuit parameters of the plate resonator by the fluid loading permits calculation of the mass density-shear viscosity product. Use of doubly rotated resonators does permit additional information to be obtained, but in no case can the viscosity and mass density values be separated. In these measurements, the resonator surface is exposed to a measurand bath whose extent greatly exceeds the penetration depth of the evanescent shear mode excited by the active element. Here we briefly review past techniques and current art, and sketch a proposal involving the interesting situation in which the separation between the resonator and a confining wall is less than the penetration depth of the fluid occupying the intervening region. To highlight the salient features of this novel case, the discussion is limited to the very idealized circumstance of a strictly 1-D problem, unencumbered by the vicissitudes inevitably encountered in practice. An appendix mentions some of these functional impedimenta and indicates how deviations from ideality might be approached in engineering embodiments. When the fluid confinement is of the order of the penetration depth, the resonator perturbation becomes a sensitive function of the separation, and it is found that viscosity and density may be separately and uniquely determined. Moreover, extreme miniaturization is a natural consequence because the penetration depth generally is on the order of micrometers for frequencies around 1 MHz at temperatures and pressures ordinarily encountered with gases and liquids. Micro-electro-mechanical (MEMS) versions of viscometers and associated types of fluid sensors are thereby enabled. PMID:20211786

  4. Computational fluid dynamics research

    NASA Technical Reports Server (NTRS)

    Chandra, Suresh; Jones, Kenneth; Hassan, Hassan; Mcrae, David Scott

    1992-01-01

    The focus of research in the computational fluid dynamics (CFD) area is two fold: (1) to develop new approaches for turbulence modeling so that high speed compressible flows can be studied for applications to entry and re-entry flows; and (2) to perform research to improve CFD algorithm accuracy and efficiency for high speed flows. Research activities, faculty and student participation, publications, and financial information are outlined.

  5. Metalworking fluid hand dermatitis.

    PubMed

    Ueno, Saori; Shiomi, Yuko; Yokota, Kozo

    2002-07-01

    In a household appliance plant, several rinse-free lubricating fluids have been used instead of neat mineral oils since 1994: mixtures of isoparaffinic hydrocarbons with 9 to 14 carbons per molecule. As such they denature keratin, irritate and defat the skin, and remove water from it. Work gloves have been worn over plastic gloves and separate, reusable, cotton inner gloves have been added to absorb sweat since skin problems were first recognized in 1994. All 74 males (mean +/- SD, 38.8 +/- 8.0 years) who work with the fluids were interviewed and given cutaneous examinations when indicated. While 4 cases of severe dermatitis and 31 cases of mild dermatitis were identified, 28 individuals gave a history of similar problems since the use of lubricating fluids. Their symptoms were typical of primary skin irritation. The hands were the commonly affected region (63 of 63 cases: 100%), followed by the thighs (15.9%) and trunk (11.1%). The work-related skin symptoms identified were less common in workers who immediately removed the liquid with soap and water, when it is spilled on the hands, than in those who did not, but the difference was not statistically significant (7/23 (30.4%) vs. 28/51 (54.9%), p=0.051 by chi-square test). Since skin contact with metalworking fluids (MWF) is often unavoidable, good personal hygiene is important in minimizing potential adverse health effects. Health education thus remains the most important preventive measure against irritant contact dermatitis among workers handling MWFs. PMID:12141380

  6. Recording fluid currents by holography

    NASA Technical Reports Server (NTRS)

    Heflinger, L. O.; Wuerker, R. F.

    1980-01-01

    Convection in fluids can be studied with aid of holographic apparatus that reveals three-dimensional motion of liquid. Apparatus eliminates images of fixed particles such as dust on windows and lenses, which might mask behavior of moving fluid particles. Holographic apparatus was developed for experiments on fluid convection cells under zero gravity. Principle is adaptable to study of fluid processes-for example, electrochemical plating and combustion in automotive engines.

  7. Hydrocarbon fluid, ejector refrigeration system

    SciTech Connect

    Kowalski, G.J.; Foster, A.R.

    1993-08-31

    A refrigeration system is described comprising: a vapor ejector cycle including a working fluid having a property such that entropy of the working fluid when in a saturated vapor state decreases as pressure decreases, the vapor ejector cycle comprising: a condenser located on a common fluid flow path; a diverter located downstream from the condenser for diverting the working fluid into a primary fluid flow path and a secondary fluid flow path parallel to the primary fluid flow path; an evaporator located on the secondary fluid flow path; an expansion device located on the secondary fluid flow path upstream of the evaporator; a boiler located on the primary fluid flow path parallel to the evaporator for boiling the working fluid, the boiler comprising an axially extending core region having a substantially constant cross sectional area and a porous capillary region surrounding the core region, the core region extending a length sufficient to produce a near sonic velocity saturated vapor; and an ejector having an outlet in fluid communication with the inlet of the condenser and an inlet in fluid communication with the outlet of the evaporator and the outlet of the boiler and in which the flows of the working fluid from the evaporator and the boiler are mixed and the pressure of the working fluid is increased to at least the pressure of the condenser, the ejector inlet, located downstream from the axially extending core region, including a primary nozzle located sufficiently close to the outlet of the boiler to minimize a pressure drop between the boiler and the primary nozzle, the primary nozzle of the ejector including a converging section having an included angle and length preselected to receive the working fluid from the boiler as a near sonic velocity saturated vapor.

  8. Fluid Film Bearing Code Development

    NASA Technical Reports Server (NTRS)

    1995-01-01

    The next generation of rocket engine turbopumps is being developed by industry through Government-directed contracts. These turbopumps will use fluid film bearings because they eliminate the life and shaft-speed limitations of rolling-element bearings, increase turbopump design flexibility, and reduce the need for turbopump overhauls and maintenance. The design of the fluid film bearings for these turbopumps, however, requires sophisticated analysis tools to model the complex physical behavior characteristic of fluid film bearings operating at high speeds with low viscosity fluids. State-of-the-art analysis and design tools are being developed at the Texas A&M University under a grant guided by the NASA Lewis Research Center. The latest version of the code, HYDROFLEXT, is a thermohydrodynamic bulk flow analysis with fluid compressibility, full inertia, and fully developed turbulence models. It can predict the static and dynamic force response of rigid and flexible pad hydrodynamic bearings and of rigid and tilting pad hydrostatic bearings. The Texas A&M code is a comprehensive analysis tool, incorporating key fluid phenomenon pertinent to bearings that operate at high speeds with low-viscosity fluids typical of those used in rocket engine turbopumps. Specifically, the energy equation was implemented into the code to enable fluid properties to vary with temperature and pressure. This is particularly important for cryogenic fluids because their properties are sensitive to temperature as well as pressure. As shown in the figure, predicted bearing mass flow rates vary significantly depending on the fluid model used. Because cryogens are semicompressible fluids and the bearing dynamic characteristics are highly sensitive to fluid compressibility, fluid compressibility effects are also modeled. The code contains fluid properties for liquid hydrogen, liquid oxygen, and liquid nitrogen as well as for water and air. Other fluids can be handled by the code provided that the

  9. 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.

  10. 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.

  11. 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.

  12. 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.

  13. 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.

  14. Amniotic fluid embolism.

    PubMed

    Clark, Steven L

    2014-02-01

    Amniotic fluid embolism remains one of the most devastating conditions in obstetric practice with an incidence of approximately 1 in 40,000 deliveries and a reported mortality rate ranging from 20% to 60%. The pathophysiology appears to involve an abnormal maternal response to fetal tissue exposure associated with breaches of the maternal-fetal physiologic barrier during parturition. This response and its subsequent injury appear to involve activation of proinflammatory mediators similar to that seen with the classic systemic inflammatory response syndrome. Progress in our understanding of this syndrome continues to be hampered by a lack of universally acknowledged diagnostic criteria, the clinical similarities of this condition to other types of acute critical maternal illness, and the presence of a broad spectrum of disease severity. Clinical series based on population or administrative databases that do not include individual chart review by individuals with expertise in critical care obstetrics are likely to both overestimate the incidence and underestimate the mortality of this condition by the inclusion of women who did not have amniotic fluid embolism. Data regarding the presence of risk factors for amniotic fluid embolism are inconsistent and contradictory; at present, no putative risk factor has been identified that would justify modification of standard obstetric practice to reduce the risk of this condition. Maternal treatment is primarily supportive, whereas prompt delivery of the mother who has sustained cardiopulmonary arrest is critical for improved newborn outcome. PMID:24402585

  15. Fluid Dynamics and Viscosity in Strongly Correlated Fluids

    NASA Astrophysics Data System (ADS)

    Schäfer, Thomas

    2014-10-01

    We review the modern view of fluid dynamics as an effective low-energy, long-wavelength theory of many-body systems at finite temperature. We introduce the concept of a nearly perfect fluid, defined by a ratio η/s of shear viscosity to entropy density of order ℏ/kB or less. Nearly perfect fluids exhibit hydrodynamic behavior at all distances down to the microscopic length scale of the fluid. We summarize arguments that suggest that there is fundamental limit to fluidity, and we review the current experimental situation of measurements of η/s in strongly coupled quantum fluids.

  16. Fluid damping and fluid stiffness of tube arrays in crossflow

    SciTech Connect

    Chen, S.S.; Zhu, S.; Jendrzejczyk, J.A.

    1994-06-01

    Motion-dependent fluid forces acting on a tube array were measured as a function of excitation frequency, excitation amplitude, and flow velocity. Fluid-damping and fluid-stiffness coefficients were obtained from measured motion-dependent fluid forces as a function of reduced flow velocity and excitation amplitude. The water channel and test setup provide a sound facility for obtaining key coefficients for fluidelastic instability of tube arrays in crossflow. Once the motion-dependent fluid-force coefficients have been measured, a reliable design guideline, based on the unsteady flow theory, can be developed for fluidelastic instability of tube arrays in crossflow.

  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. 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.

  20. 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

  1. Fluid mechanics revisited

    NASA Astrophysics Data System (ADS)

    Brenner, Howard

    2006-10-01

    Öttinger's recent nontraditional incorporation of fluctuations into the formulation of the friction matrix appearing in the phenomenological GENERIC theory of nonequilibrium irreversible processes is shown to furnish transport equations for single-component gases and liquids undergoing heat transfer which support the view that revisions to the Navier-Stokes-Fourier (N-S-F) momentum/energy equation set are necessary, as empirically proposed by the author on the basis of an experimentally supported theory of diffuse volume transport. The hypothesis that the conventional N-S-F equations prevail without modification only in the case of “incompressible” fluids, where the density ρ of the fluid is uniform throughout, serves to determine the new phenomenological parameter α‧ appearing in the GENERIC friction matrix. In the case of ideal gases the consequences of this constitutive hypothesis are shown to yield results identical to those derived theoretically by Öttinger on the basis of a “proper” coarse-graining of Boltzmann's kinetic equation. A major consequence of the present work is that the fluid's specific momentum density v is equal to its volume velocity vv, rather than to its mass velocity vm, contrary to current views dating back 250 years to Euler. In the case of rarefied gases the proposed modifications are also observed to agree with those resulting from Klimontovich's molecularly based, albeit ad hoc, self-diffusion addendum to Boltzmann's collision integral. Despite the differences in their respective physical models-molecular vs. phenomenological-the role played by Klimontovich's collisional addition to Boltzmann's equation in modifying the N-S-F equations is noted to constitute a molecular counterpart of Öttinger's phenomenological fluctuation addition to the GENERIC friction matrix. Together, these two theories collectively recognize the need to address multiple- rather than single- encounter collisions between a test molecule and its

  2. 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.

  3. 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.

  4. 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

  5. The "Conservatoire National des Arts et Metiers"

    ERIC Educational Resources Information Center

    Kuhn, Gerard

    2004-01-01

    The overall mission of the Conservatoire national des arts et metiers--(CNAM) [National Conservatory of Industrial Arts and Trades] is outlined. One of its centers, the "Centre national de l'entrepreneuriat"--(CNE) [National Center for Entrepreneurship] is described in greater detail. In particular, this center offers various services, notably…

  6. Heat transfer fluids containing nanoparticles

    DOEpatents

    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.

  7. 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.

  8. Plane waves in noncommutative fluids

    NASA Astrophysics Data System (ADS)

    Abdalla, M. C. B.; Holender, L.; Santos, M. A.; Vancea, I. V.

    2013-08-01

    We study the dynamics of the noncommutative fluid in the Snyder space perturbatively at the first order in powers of the noncommutative parameter. The linearized noncommutative fluid dynamics is described by a system of coupled linear partial differential equations in which the variables are the fluid density and the fluid potentials. We show that these equations admit a set of solutions that are monochromatic plane waves for the fluid density and two of the potentials and a linear function for the third potential. The energy-momentum tensor of the plane waves is calculated.

  9. 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.

  10. 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.